For most substances in the universe, the solid phase is denser than the liquid phase.
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The newest paper, on which Novoselov is a co-author, focuses only on the "liquid phase exfoliation," the slicing graphite method.
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The extreme conditions around young stars sometimes means that water goes directly from gas into snow and ice, skipping the liquid phase entirely.
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It's a process known as sublimation, and it occurs when temperatures and pressures are just right so that materials skip the liquid phase of the transition process.
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Crystallization is a dramatic switch from the liquid phase, in which molecules are disordered and free flowing, to the crystal phase, in which molecules are locked in a regular, repeating pattern.
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Foam is a type of colloidal dispersion where gas is dispersed throughout a liquid phase. The liquid phase is also called the continuous phase because it is an uninterrupted, unlike the gas phase.
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The selecting of filter press type depends on the value of liquid phase or the solid phase. If extracting liquid phase is desired, then filter press is among the most appropriate methods to be used.
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However, liquid phase synthesis may also be used for specific needs.
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Water, on the other hand, passes through a liquid phase at 1 atmosphere.
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The influence of drugs on cancer cells has been studied with liquid-phase ESEM- STEM.
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Densities of the liquid phase and vapor phase become equal at critical point of drying.
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The adsorption of molecules of liquid phase at an interface occurs when this liquid phase is in contact with other immiscible phases that may be gas, liquid, or solidChattoraj, D.K. and Birdi, K.S. Adsorption and the Gibbs Surface Excess. New York: Plenum Publishing Company, 1984.
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Bubble column reactor for photochlorination. Photochlorinations are usually effected in the liquid phase, usually employing inert solvents.
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All lipids have a characteristic temperature at which they transition (melt) from the gel to liquid phase. In both phases the lipid molecules are prevented from flip- flopping across the bilayer, but in liquid phase bilayers a given lipid will exchange locations with its neighbor millions of times a second. This random walk exchange allows lipid to diffuse and thus wander across the surface of the membrane. Unlike liquid phase bilayers, the lipids in a gel phase bilayer have less mobility.
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In a mineral, nearly all elements distribute unevenly between the solid and liquid phase. This phenomenon known as chemical fractionation and can be described by an equilibrium constant, K which sets a fixed distribution of an element between any two phases at equilibrium. A distribution constant K_D is used to define the relationship between the solid and liquid phase of a reaction. This value is essentially a ratio of the concentration of an element between two phases, typically between the solid and liquid phase in this context.
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Schematics of a plate column with bubble cap trays. The feed to the column can be liquid, gas or gas and liquid at equilibrium. Inside the column there are instead always two phases: one gas phase and one liquid phase. The liquid phase flows downward through the column via gravity, while the gas phase flows upward.
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Due to symmetry, the shifts become averaged to zero in the liquid phase, so NQR spectra can only be measured for solids.
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The mould inserts are produced by means of powder metallurgy, i.e. a sintering process followed by post- machining processes and sophisticated grinding operations. Most commonly a metallic binder (usually cobalt) is added in liquid phase sintering. In this process, the metallic binder improves the toughness of the mould as well as the sintering quality in the liquid phase to fully dense material.
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She also worked on a new laser-cured protein solder for microsurgery, as well as thin film wave guides grown by liquid phase epitaxy.
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Chen J. (1995). "Development of fungal degrading system to detoxify 2,4,6-trinitrotoluene (TNT) in liquid phase bioreactors". PhD dissertation, Texas A&M; University. 127 pp.
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There are many theories on the kinetics of the bonding process but the most common theory divides the process into four main stages.MacDonald W.D., and Eager, " T.W. Transient liquid phase bonding. Annual Review of Materials Science ". 22 (1) (1992), 23-46 Tuah-poku, I., Dollar, M., Massalski, T.B. " A study of the transient liquid phase bonding process applied to Ag/Cu/Ag sandwich joint".
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Curini, M.; Rosati, O.; Costantino, U., Heterogeneous Catalysis in Liquid Phase Organic Synthesis, Promoted by Layered Zirconium Phosphates and Phosphonates. Curr. Org. Chem. 2004, 8, 591-606.
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For instance, cyclohexane has been converted to cyclohexanone and cyclohexanol with a combined selectivity of ~100% on gold catalysts. Product selectivities can be tuned in liquid phase reactions by the presence or absence of solvent and by the nature of the latter, viz. water, polar, or nonpolar. With gold catalysts, the catalyst's support has less influence on reactions in the liquid phase than on reactions in the gas phase.
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S. Jezierski, L. Gitlin, S. Nagl, D. Belder, Multistep liquid-phase lithography for fast prototyping of microfluidic free-flow-electrophoresis chips, Anal. Bioanal. Chem., 2011, 401, 2651-2656.
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Solid–liquid phase diagram of sodium and potassiumG.L.C.M. van Rossen, H. van Bleiswijk: Über das Zustandsdiagramm der Kalium-Natriumlegierungen, in: Z. Anorg. Chem., 1912, 74, S. 152–156.
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Then a liquid phase process was introduced using zeolite catalysts. This offers low benzene-to-ethylene ratios, reducing the size of the required equipment and lowering byproduct production.
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This phenomenon, known as Abnormal grain growth, or AGG results in a bimodal grain size distribution which has consequences on the mechanical performance of the sintered object. For densification to occur at a quick pace it is essential to have (1) an amount of liquid phase that is large in size, (2) a near complete solubility of the solid in the liquid, and (3) wetting of the solid by the liquid. The power behind the densification is derived from the capillary pressure of the liquid phase located between the fine solid particles. When the liquid phase wets the solid particles, each space between the particles becomes a capillary in which a substantial capillary pressure is developed.
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The TiO2 nanowire arrays are grown on the optical fiber using liquid phase deposition method and platinum is coated on the inwall of stainless steel capillary tubes using electroless deposition.
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When water vapor condenses (an equilibrium fractionation), the heavier water isotopes (H218O and 2H2O) become enriched in the liquid phase while the lighter isotopes (H216O and 1H2O) tend toward the vapor phase.
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The solid phase particles are placed in a column where liquid phase is pumped in from the bottom and exits at the top. The gravity of the particles ensure that the solid phase does not exit the column with the liquid phase. Affinity columns can be eluted by changing salt concentrations, pH, pI, charge and ionic strength directly or through a gradient to resolve the particles of interest. More recently, setups employing more than one column in series have been developed.
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A feature of the LHPG technique is its high convection speed in the liquid phase due to Marangoni convection. The video presented in the following reference shows the liquid phase convection during lithium niobate (LiNbO3) fiber pulling using a very small piece of platinum wire inside the liquid that is allowed to spin. It is possible to see that it spins very fast. Even when it appears to be standing still, it is in fact spinning fast on its axis.
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In separated (i.e., non-homogeneous) flow, it is related to volumetric flow rates of the gas and the liquid phase, and to the ratio of the velocity of the two phases (called slip ratio).
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Most of the meters use differential pressure for the gas phase and a form of liquid detection or wet gas density measurement for the liquid phase normally utilising one of the techniques listed above.
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Depending on the morphology of the reactants, it is possible to initiate a SHS reaction where a liquid phase occurs prior to phase formation or to directly result in solid-phase products without any melt.
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Through the degradation process, phosphorene (solid) reacts with oxygen/water to develop liquid phase acid 'bubbles' on the surface, and finally evaporate (vapor) to fully vanish (S-B-V degradation) and severely reducing overall quality.
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A typical example of wet gas flows are in the production of natural gas in the oil and gas industry. Natural gas is a mixture of hydrocarbon compounds with quantities of various non hydrocarbons. This exists in either a gaseous or liquid phase or in solution with crude oil in porous rock formations. The amount of hydrocarbons present in the liquid phase of the wet gas extracted depends on the reservoir temperature and pressure conditions, which change over time as the gas and liquid are removed.
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All lipids have a characteristic temperature at which they undergo a transition (melt) from the gel to liquid phase. In both phases the lipid molecules are constrained to the two dimensional plane of the membrane, but in liquid phase bilayers the molecules diffuse freely within this plane. Thus, in a liquid bilayer a given lipid will rapidly exchange locations with its neighbor millions of times a second and will, through the process of a random walk, migrate over long distances.H. C. Berg, "Random Walks in Biology".
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Unlike liquid phase bilayers, the lipids in a gel phase bilayer are locked in place and exhibit neither flip-flop nor lateral mobility. Due to this limited mobility, gel bilayers lack an important property of liquid bilayers: the ability to reseal small holes. Liquid phase bilayers can spontaneously heal small voids, much the same way a film of oil on water could flow in to fill a gap. This functionality is one of the reasons that cell membranes are usually composed of fluid phase bilayers.
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"Principles of Hydraulic Design of Multiphase- Flow Transmission Pipelines". University of Tehran Press, 2002 Depending on the pressure and temperature of the reservoir, the amount of dissolved in the liquid phase and free gases will be different.
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InSb can be grown by solidifying a melt from the liquid state (Czochralski process), or epitaxially by liquid phase epitaxy, hot wall epitaxy or molecular beam epitaxy. It can also be grown from organometallic compounds by MOVPE.
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The active species in these catalysts were identified to be hemispherical gold nano-crystals of less than 2 nm in diameter in intimate contact with the support. Alkene epoxidation has been demonstrated in absence of H2 reuductant in the liquid phase. For example, using 1% Au/graphite, ~80% selectivities of cis-cyclooctene to cyclooctene oxide (analogous to cyclohexene oxide) were obtained at 7-8% conversion, 353 K (80 °C), and 3 MPa O2 in absence of hydrogen or solvent. Other liquid-phase selective oxidations have been achieved with saturated hydrocarbons.
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Here a reaction at a triple interface between a conductive solid, droplets of a redox active liquid phase and an electrolyte solution have been used to determine the energy required to transfer a charged species across the interface.
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In-situ experiments may also be conducted in TEM using differentially pumped sample chambers, or specialized holders. Types of in-situ experiments include studying nanomaterials, biological specimens, and chemical reactions using liquid-phase electron microscopy, and material deformation testing.
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In the early 1960s liquid phase epitaxy (LPE) was invented by Herbert Nelson of RCA Laboratories. By layering the highest quality crystals of varying compositions, it enabled the demonstration of the highest quality heterojunction semiconductor laser materials for many years.
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Metal borate thin films have been grown by a variety of techniques, including liquid-phase epitaxy (e.g. FeBO3, β‐BaB2O4), electron- beam evaporation (e.g. CrBO3, β‐BaB2O4), pulsed laser deposition (e.g. β‐BaB2O4, Eu(BO2)3), and atomic layer deposition (ALD).
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Sublimation is a direct phase transition from the solid phase to the gas phase, skipping the intermediate liquid phase. Because it does not involve the liquid phase, it is not a form of vaporization. The term vaporization has also been used in a colloquial or hyperbolic way to refer to the physical destruction of an object that is exposed to intense heat or explosive force, where the object is actually blasted into small pieces rather than literally converted to gaseous form. Examples of this usage include the "vaporization" of the uninhabited Marshall Island of Elugelab in the 1952 Ivy Mike thermonuclear test.
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Hence as long as the film is thin compared to the frequency interaction from the solid to the whole film is possible. But when d gets large compared to typical VUV frequencies the electronic structure of the film will be too slow to pass the high frequencies to the other end of the liquid phase. Thus this end of the liquid phase feels only a retarded van der Waals interaction with the solid phase. Hence the attraction between the liquid molecules themselves will predominate and they will start forming droplets instead of thickening the film further.
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The sintering of liquid-phase materials involves a fine- grained solid phase to create the needed capillary pressures proportional to its diameter, and the liquid concentration must also create the required capillary pressure within range, else the process ceases. The vitrification rate is dependent upon the pore size, the viscosity and amount of liquid phase present leading to the viscosity of the overall composition, and the surface tension. Temperature dependence for densification controls the process because at higher temperatures viscosity decreases and increases liquid content. Therefore, when changes to the composition and processing are made, it will affect the vitrification process.
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The ratio r = LDL / (LDL + HDL) of phase amounts is determined according to the thermodynamic equilibrium of the system, which is often governed by external variables such as pressure and temperature. A discontinuity is present in r when crossing the liquid–liquid phase transition, which separates the LDL-rich phase from the LDL-poor phase. At any point of the liquid–liquid phase transition, including the associated liquid–liquid critical point, the ratio of LDL to HDL is exactly one (r = 1/2). The liquid–liquid critical point theory can be applied to all liquids that possess the tetrahedral symmetry.
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Even at equilibrium molecules are constantly in motion and, once in a while, a molecule in the liquid phase gains enough kinetic energy to break away from the liquid phase and enter the gas phase. Likewise, every once in a while a vapor molecule collides with the liquid surface and condenses into the liquid. At equilibrium, evaporation and condensation processes exactly balance and there is no net change in the volume of either phase. At room temperature and pressure, the water jar reaches equilibrium when the air over the water has a humidity of about 3%.
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On the other hand, if the propellants are cooled sufficiently, they exist in the liquid phase at higher density and lower pressure, simplifying tankage. These cryogenic temperatures vary depending on the propellant, with liquid oxygen existing below and liquid hydrogen below . Since one or more of the propellants is in the liquid phase, all cryogenic rocket engines are by definition either liquid-propellant rocket engines or hybrid rocket engines. Various cryogenic fuel-oxidizer combinations have been tried, but the combination of liquid hydrogen (LH2) fuel and the liquid oxygen (LOX) oxidizer is one of the most widely used.
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Direct hydration reacts propene and water, either in gas or liquid phase, at high pressures in the presence of solid or supported acidic catalysts. This type of process usually requires higher- purity propylene (> 90%). Direct hydration is more commonly used in Europe.
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Epitaxial silicon is usually grown using vapor-phase epitaxy (VPE), a modification of chemical vapor deposition. Molecular-beam and liquid-phase epitaxy (MBE and LPE) are also used, mainly for compound semiconductors. Solid-phase epitaxy is used primarily for crystal-damage healing.
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The Stretford process was developed at the North-Western Gas Board's laboratories in Stretford during the 1940s. It was the first liquid phase oxidation process for removing hydrogen sulphide (H2S) from town gas to be commercially successful. Many Stretford plants were built worldwide.
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Immiscible CO2 helps to saturate oil, resulting in swelling and reduction of viscosity of the liquid phase and consequently improving mobilization by extra driving pressure. Concomitantly, other gases and solvents may dissolve carbonate rock, leading to an increase in rock permeability and porosity.
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For peptides three main types of methods are used, namely chemical synthesis, extraction from natural substances, and biosynthesis. Chemical synthesis is used for smaller peptides made of up to 30–40 amino acids. One distinguishes between “liquid phase” and “solid phase” synthesis.
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Patchy particles range in valency from two (Janus particles) or higher. Patchy particles of valency three or more experience liquid-liquid phase separation. Some phase diagrams of patchy particles do not follow the law of rectilinear diameters. Schematic depiction of modifying a spherical (e.g.
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The SO2 is chemically bound in the solution and readily available to react with H2S. The process is operated with an excess amount of SO2 in the solution so that there will always be sufficient amount for the liquid phase Claus reaction with H2S.
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This means that compatible elements have a value of D\gg1. Thus, incompatible elements are concentrated in the melt, whereas compatible elements tend to be concentrated in the solid. Compatible elements with D\gg1 are strongly fractionated and have very low concentrations in the liquid phase.
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When the requirement is to concentrate a liquid phase, fractional freezing can be useful due to its simplicity. Fractional freezing is also used in the production of fruit juice concentrates and other heat-sensitive liquids, as it does not involve heating the liquid (as happens during evaporation).
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New York: Academic, 1965, p. 245, . Such a soluble cell extract is not identical to the soluble part of the cell cytoplasm and is usually called a cytoplasmic fraction. The term cytosol is now used to refer to the liquid phase of the cytoplasm in an intact cell.
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Flocculation is the accumulation of drops within a continuous liquid phase. Creaming is the accumulation of drops at the top of a liquid continuous phase. Coalescence is the merging of two drops into one single drop. Demulsification is when the dispersed phase completely coalesces into one continuous phase.
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This is olive brown in colour. When heated to 250 °C it recrystallizes to another yellow form. Cuprous sufoxylate Cu2SO2 can be made as a solid or liquid by heating cuprous sulfide and copper sulfate. Cu2SO2 melts at and is stable as a liquid phase to over 680K.
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For some examples of this effect, see liquid-liquid extraction. It is possible to extract a solute from one liquid phase to another without a chemical reaction. Examples of such solutes are noble gases and osmium tetroxide. The process of absorption means that a substance captures and transforms energy.
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E Lascaris et al (2015) Diffusivity and short-time dynamics in two models of silica, JOURNAL OF CHEMICAL PHYSICS, 142(10), art 104506I Saika-Voivod et al (2001) Computer simulations of liquid silica: Equation of state and liquid-liquid phase transition, PHYSICAL REVIEW E, 63(1), art 011202.
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Planetary scientists have not reached a consensus on whether Earth-like exoplanets have plate tectonics, but it is widely thought that the likelihood of plate tectonics on an Earth-like exoplanet is a function of planetary radius, initial temperature upon coalescence, insolation, and presence or absence of liquid-phase surface water.
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Vaporization (or vaporisation) of an element or compound is a phase transition from the liquid phase to vapor.Britannica: Vaporization There are two types of vaporization: evaporation and boiling. Evaporation is a surface phenomenon, whereas boiling is a bulk phenomenon. A laboratory flask filled with pure bromine, a liquid that evaporates rapidly.
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Although nitrate salts have been the medium of choice since the early 1980s, they freeze at and thus require heating to prevent solidification. Ionic liquids such as [] have more favorable liquid-phase temperature ranges (-75 to 459 °C) and could therefore be excellent liquid thermal storage media and heat transfer fluids.
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Electrical mobility is the ability of charged particles (such as electrons or protons) to move through a medium in response to an electric field that is pulling them. The separation of ions according to their mobility in gas phase is called ion mobility spectrometry, in liquid phase it is called electrophoresis.
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These new instruments had a major impact on the emerging fields of proteomics and genomics. The gas-liquid phase protein sequencer was developed with Michael W. Hunkapiller, then a research fellow at Caltech. The instrument makes use of the chemical process known as the Edman degradation, devised by Pehr Edman.
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Dioscorea zingiberensis, is a species of yam, a tuberous root vegetable. It has been cultivated in China for the production of diosgenin,Liu, L., Dong, Y., 375 Xiu, Z., 2010. Three-liquid-phase extraction of diosgenin and steroidal saponins from fermentation of Dioscorea zingibernsis C.H. Wright. Process Biochemistry 45, 752–756.
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It is both elastic and viscous yet flows smoothly in the liquid phase. Most importantly lignin can improve on the current standards of plastics because it is antimicrobial in nature. It is being produced at such great quantities and is readily available for use as an emerging environmentally friendly polymer.
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The continuous liquid phase is held to the bubble surfaces by the surfactant molecules that make up the solution being foamed. This fixation is important because otherwise the foam becomes very unstable as the liquid drains into the plateau region making the lamellae thin. Once the lamellae become too thin they will rupture.
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Packaging air pillow made of PLA-blend bio-flex Biodegradation of any plastic is a process that happens at solid/liquid interface whereby the enzymes in the liquid phase depolymerize the solid phase Degli-Innocenti, Francesco. “Biodegradation of Plastics and Ecotoxicity Testing: When Should It Be Done.” Frontiers in Microbiology, vol. 5, no.
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At very low concentration the particles have the tendency to develop a dendritic-like morphology, as reported in the images. Barium titanate can be synthesized by the relatively simple sol–hydrothermal method. Barium titanate can also be manufactured by heating barium carbonate and titanium dioxide. The reaction proceeds via liquid phase sintering.
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This allows for the microfilariae that would have been in the tissue to migrate to the liquid phase of the specimen. Additionally, to differentiate the skin-dwelling filariae M. streptocerca and Onchocerca volvulus, a nested polymerase chain reaction (PCR) assay was developed using small amounts of parasite material present in skin biopsies.
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In liquids, the cloud point is the temperature below which a transparent solution undergoes either a liquid-liquid phase separation to form an emulsion or a liquid-solid phase transition to form either a stable sol or a suspension that settles a precipitate. The cloud point is analogous to the 'dew point' at which a gas-liquid phase transition called condensation occurs in water vapour (humid air) to form liquid water (dew or clouds). When the temperature is below zero degrees Celsius, the dew point is called the frost point, as water vapour undergoes gas-solid phase transition called deposition, solidification, or freezing. In the petroleum industry, cloud point refers to the temperature below which wax in diesel or biowax in biodiesels forms a cloudy appearance.
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Transient liquid phase diffusion bonding (TLPDB) is a joining process that has been applied for bonding many metallic and ceramic systems which cannot be bonded by conventional fusion welding techniques. The bonding process produces joints with a uniform composition profile, tolerant of surface oxides and geometrical defects. The bonding technique has been exploited in a wide range of applications, from the production and repair of turbine engines in the aerospace industry to the atomic nuclear power plantsMazar Atabaki, M. "Microstructural evolution in the partial transient liquid phase diffusion bonding of Zircaloy-4 to stainless steel 321 using active titanium filler metal". Journal of Nuclear Materials, 406(3) (2010), 330-344 and the connection of circuit lines in the microelectronics industry.
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The condition relates activity coefficients in liquid phase to total pressure and the vapour pressures of pure components. Total vapor pressure of mixtures as a function of composition at a chosen constant temperature Azeotropes can form only when a mixture deviates from Raoult's law, the equality of compositions in liquid phase and vapor phases, in vapour-liquid equilibrium and Dalton's law the equality of pressures for total pressure being equal to the sum of the partial pressures in real mixtures. In other words: Raoult's law predicts the vapor pressures of ideal mixtures as a function of composition ratio. More simply: per Raoult's law molecules of the constituents stick to each other to the same degree as they do to themselves.
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The heat transport equation considers conduction as well as advection with flowing water. The solute transport equations assume advective-dispersive transport in the liquid phase, and diffusion in the gaseous phase. The transport equations further include provisions for nonlinear and/or non-equilibrium reactions between the solid and liquid phases, linear equilibrium reactions between the liquid and gaseous phases, zero-order production, and two first-order degradation reactions: one which is independent of other solutes, and one which provides the coupling between solutes involved in sequential first order decay reactions. In addition, physical non-equilibrium solute transport can be accounted for by assuming a two-region, dual-porosity type formulation which partitions the liquid phase into mobile and immobile regions.
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The two liquid phases are separated using a dual discharge system where the lighter liquid phase such as oil, is separated over a ring dam via gravity, and water, which is commonly the heavier liquid phase, is discharged using a stationary impeller under pressure. Each of the three components, solid, oil and water, are distributed to different storage tanks. There are numerous manufacturers specialising in mechanical separation technology that have adopted these new designs into industry standard equipment. This advanced technology has allowed decanter centrifuges to operate up to 250 cubic metres per hour and has developed numerous designs such as the Z8E decanter, known as the world's largest decanter centrifuge with an adjustable impeller, which supplies a torque of 24,000 newton metres.
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A gas–liquid contactor is a particular chemical equipment used to realize the mass and heat transfer between a gas phase and a liquid phase. Gas–liquid contactors can be used in separation processes (e.g. distillation, absorption) or as gas–liquid reactors or to achieve both purposes within the same device (e.g. reactive distillation).
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It is an overlapping PCR method. It does not require a culture step because it sequences the whole viral genome directly from the clinical sample. Small oligonucleotides, complementary to the target, are used as probes for a hybridization reaction. The probes can be bound to a solid phase or to magnetic beads in liquid phase.
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HSMG (High Strength Metallurgical Graphene) – polycrystalline graphene, grown from a liquid phase. This process, in comparison to other methods based on using solid substrates, allows to manufacture defect-free graphene structures. HSMG is formed on a perfectly flat surface - liquid metal. While growing graphene on solid substrates is difficult due to surface irregularities and defects.
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Graduated cylinders and beakers filled with chemicals Wet chemistry is a form of analytical chemistry that uses classical methods such as observation to analyze materials. It is called wet chemistry since most analyzing is done in the liquid phase. Wet chemistry is also called bench chemistry since many tests are performed at lab benches.
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Molten FLiBe (2LiF-BeF2) Molten salt is salt which is solid at standard temperature and pressure but enters the liquid phase due to elevated temperature. A salt that is normally liquid even at standard temperature and pressure is usually called a room temperature ionic liquid, although technically molten salts are a class of ionic liquids.
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Ambient temperature molten salts (also known as ionic liquids) are present in the liquid phase at standard conditions for temperature and pressure. Examples of such salts include N-ethylpyridinium bromide and aluminium chloride mix, discovered in 1951Hurley, F. H.; Wier, T. P. J. Electrochem. Soc. 1951, 98, 203. and ethylammonium nitrate discovered by Paul Walden.
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Semi-crystalline polymers can undergo crystallization and melting transitions, whereas amorphous polymers do not. In polymers, crystallization and melting do not suggest solid-liquid phase transitions, as in the case of water or other molecular fluids. Instead, crystallization and melting refer to the phase transitions between two solid states (i.e., semi-crystalline and amorphous).
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Thickening agents are often used as food additives and in cosmetics and personal hygiene products. Some thickening agents are gelling agents, forming a gel. The agents are materials used to thicken and stabilize liquid solutions, emulsions, and suspensions. They dissolve in the liquid phase as a colloid mixture that forms a weakly cohesive internal structure.
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A flammable liquid is a liquid with flash point of not more than 60.5 °C (141 °F), or any material in a liquid phase with a flash point at or above 37.8 °C (100 °f) that is intentionally heated and offered for transportation or transported at or above its flash point in a bulk packaging.
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Supported liquid membranes consist of a solid and liquid phase contained within a microporous separator. Some polymer electrolytes form complexes with alkali metal salts, which produce ionic conductors that serve as solid electrolytes. Solid ion conductors, can serve as both separator and the electrolyte. Separators can use a single or multiple layers/sheets of material.
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R. Koningsveld, A. J. Staverman, Liquid-Liquid Phase Separation in Multicomponent Polymer Solutions. II. The Critical State, Journal Polymer Science, Polymer Physics Editions, 1968, Volume 6, pp 325-347. or polymethylmethacrylate in acetonitrile.T. G. Fox, Properties of dilute polymer solutions III: Intrinsic viscosity/temperature relationships for conventional polymethylmethacrylate, Polymer, 1962, Volume 3, pp 111-128.
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As expected, we see that vc decreases as particle radius R goes up. Schematic of a particle within the liquid phase interacting with an oncoming solidification front. Waschkies et al. studied the structure of dilute to concentrated freeze-casts from low (< 1 μm s−1) to extremely high (> 700 μm s−1) solidification velocities.
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This gel is a bi-phasic system containing both a liquid phase (solvent) and a solid phase (integrated network, typically polymer network). The proportion of liquid is reduced stepwise. The rest of the liquid can be removed by drying and can be coupled with a thermal treatment to tailor the material properties of the solid.
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After obtaining his PhD, Kroto spent two-years in a postdoctoral position at the National Research Council in Ottawa, Canada carrying out further work in molecular spectroscopy, and also spent the subsequent year at Bell Laboratories in New Jersey (1966–1967) carrying out Raman studies of liquid phase interactions and worked on quantum chemistry.
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Glow-discharge radiation, γ-radiation, and ultraviolet irradiation have been used. These methods avoid the use of catalysts and solvent, but require low temperatures to produce regular polymers. Gas-phase polymerization typically produces irregular cuprene, whereas liquid-phase polymerization, conducted at −78 °C produces linear cis-polyacetylene, and solid-phase polymerization, conducted at still lower temperature, produces trans-polyacetylene.
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However, recovering the olefins for use as chemicals in, e.g., polymerization processes is advantageous today. The second direction of iron catalyst development has aimed at highest catalyst activity to be used at low reaction temperature where most of the hydrocarbon product is in the liquid phase under reaction conditions. Typically, such catalysts are obtained through precipitation from nitrate solutions.
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Steam Traps operate on the difference of properties between steam and condensate. Condensate will collect at the lowest point since steam is about 1600 times greater in volume than its liquid phase. Steam properties also change with pressure, at different pressures there are different boiling points. Steam traps can be split into 3 main categories; Mechanical, Thermodynamic, and Thermostatic.
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From 1970, Patashinski and his students B. Shumilo, A. Mitus, L.Son studied the local structure of liquids and glasses, and predicted liquid-liquid phase transitions with changes of this structure; this prediction was later confirmed by experiments. In 1992, together with Kalle Levon and Alla Margolina, Patashinski proposed the concept of double percolation for conductive polymers.
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Colloidal silicas are suspensions of fine amorphous, nonporous, and typically spherical silica particles in a liquid phase. Schematic representation of the silica gel surface. The surface of colloidal silica in contact with water is covered by siloxane bonds (≡Si–O–Si≡) and silanol groups (≡Si–OH). This makes colloidal silica very hydrophilic and capable of forming numerous hydrogen bonds.
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Membrane distillation (MD) is a thermally driven separation process in which separation is driven by phase change. A hydrophobic membrane presents a barrier for the liquid phase, allowing the vapour phase (e.g. water vapour) to pass through the membrane's pores. The driving force of the process is a partial vapour pressure difference commonly triggered by a temperature difference.
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Heat distribution throughout the corium mass is influenced by different thermal conductivity between the molten oxides and metals. Convection in the liquid phase significantly increases heat transfer. The molten reactor core releases volatile elements and compounds. These may be gas phase, such as molecular iodine or noble gases, or condensed aerosol particles after leaving the high temperature region.
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The salt is fed into the distillation column at a steady rate by adding it to the reflux stream at the top of the column. It dissolves in the liquid phase, and since it is non-volatile, flows out with the heavier bottoms stream. The bottoms are partially or completely evaporated to recover the salt for reuse.
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While holding the temperature above the filler metal melting point, interdiffusion shifts the composition away from eutectic, so solidification occurs at the process temperature. If sufficient interdiffusion occurs, the joint will remain solid and strong well above the original melt process temperature. This is why it is termed "transient liquid phase." The liquid solidifies before cooling.
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Preparative- scale ion exchange column used for protein purification. Ion exchange chromatography can be used to separate proteins because they contain charged functional groups. The ions of interest (in this case charged proteins) are exchanged for another ions (usually H+) on a charged solid support. The solutes are most commonly in a liquid phase, which tends to be water.
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Water vapor from humid winter-air deposits directly into a solid, crystalline frost pattern on a window, without ever being liquid in the process. Deposition is the phase transition in which gas transforms into solid without passing through the liquid phase. Deposition is a thermodynamic process. The reverse of deposition is sublimation and hence sometimes deposition is called desublimation.
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These properties are colligative in systems where the solute is essentially confined to the liquid phase. Boiling point elevation (like vapour pressure lowering) is colligative for non-volatile solutes where the solute presence in the gas phase is negligible. Freezing point depression is colligative for most solutes since very few solutes dissolve appreciably in solid solvents.
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The iron ions in the two coordination sites exhibit different spins, resulting in magnetic behavior. YIG is a ferrimagnetic material having a Curie temperature of 550 K. Another example is gadolinium gallium garnet, 32(GaO4)3 which is synthesized for use as a substrate for liquid-phase epitaxy of magnetic garnet films for bubble memory and magneto-optical applications.
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However, the vapor content is relatively small and the continuous phase remains the liquid phase. The vapor content of the PHW-CANDU reactor is about 0.03-0.04 kg steam / kg of agent, thus increasing the amount of heat transported by the unit mass of agent by over 10%. If the cooled surface temperature far exceeds the boiling temperature of the cooling agent in the channel section, the vapor content of the agent increases considerably, the continuous phase becoming the vapor phase and the liquid phase becoming only a suspension between vapors. The cooled surface remains covered with a liquid film which still provides a very high heat transfer coefficient, \thicksim6\cdot10^4 W/m^2\cdot K at BWR compared to \thicksim3\cdot10^4 W/m^2\cdot K at PWR.
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The presence of gas around a specimen creates new possibilities unique to ESEM: (a) liquid-phase electron microscopy is possible since any pressure greater than 609 Pa allows water to be maintained in its liquid phase for temperatures above 0 °C, in contrast to the SEM where specimens are desiccated by the vacuum condition. (b) Electrically non-conductive specimens do not require the preparation techniques used in SEM to render the surface conductive, such as the deposition of a thin gold or carbon coating, or other treatments, techniques which also require vacuum in the process. Insulating specimens charge up by the electron beam making imaging problematic or even impossible. (c) The gas itself is used as a detection medium producing novel imaging possibilities, as opposed to vacuum SEM detectors.
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For laboratory quantities, up to 40 are possible. In order to prepare larger peptides, individual fragments are first produced, purified, and then combined to the final molecule by liquid phase synthesis. Thus, for the production of Roche’s anti-AIDS drug Fuzeon (enfuvirtide), three fragments of 10–12 amino acids are first made by solid-phase synthesis and then linked together by liquid-phase synthesis. The preparation of the whole 35 amino acid peptide requires more than 130 individual steps. Microreactor Technology (MRT), making part of “process intensification”, is a relatively new tool that is being developed at several universities,Examples: Swiss Federal Institute of Technology (ETHZ), Switzerland; Massachusetts Institute of Technology (MIT), USA; Institut für Mikrotechnik (IMM), Germany; University of Washington (WU), USA; Micro-Chemical ProcessTechnology Research Association (MCPT), Japan.
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The IsoBoost system employs a liquid phase turbocharger with maximum flexibility. The device recovers energy in acid gas treatment processes at up to 80 percent efficiency, increasing productivity and profitability and reducing the carbon footprint created during the processes. Energy Transfer partners’ Jackalope plant in Hebronville, Texas, installed IsoBoost in 2008, and the plant’s total maintenance costs have fallen by 67 percent.
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During magma crystallization, caesium is concentrated in the liquid phase and crystallizes last. Therefore, the largest deposits of caesium are zone pegmatite ore bodies formed by this enrichment process. Because caesium does not substitute for potassium as readily as rubidium does, the alkali evaporite minerals sylvite (KCl) and carnallite () may contain only 0.002% caesium. Consequently, caesium is found in few minerals.
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Columns of this scale category are distinguished by their small dimensions in comparison to chromatography columns intended for larger scales as well as relatively high pressure tolerance and selection of materials in contact with the liquid phase. This is especially important for applications in the biopharmaceutical industry which underlie close scrutiny by regulatory agencies (U.S. Food and Drug Administration; European Medicines Agency).
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Thermotropic phases are those that occur in a certain temperature range. If the temperature rise is too high, thermal motion will destroy the delicate cooperative ordering of the LC phase, pushing the material into a conventional isotropic liquid phase. At too low temperature, most LC materials will form a conventional crystal. Many thermotropic LCs exhibit a variety of phases as temperature is changed.
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Solids requiring a high degree of digestion can remain in the reactors for periods up to 90 days. Sugars dissolved in the liquid waste stream can be converted into gas quickly in the liquid phase which can exit the system in less than a day. UASB reactors are typically suited to dilute waste water streams (3% TSS with particle size >0.75mm).
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Ethanol and dimethyl ether, two chemicals with the same formula (C2H6O), have different volatilities due to the different interactions that occur between their molecules in the liquid phase: ethanol molecules are capable of hydrogen bonding while dimethyl ether molecules are not. The result in an overall stronger attractive force between the ethanol molecules, making it the less volatile substance of the two.
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Recent research has demonstrated that complete dehydration prior to blending with gasoline is not always necessary. Instead, the azeotropic mixture can be blended directly with gasoline so that liquid-liquid phase equilibrium can assist in the elimination of water. A two-stage counter-current setup of mixer-settler tanks can achieve complete recovery of ethanol into the fuel phase, with minimal energy consumption.
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Stripping works on the basis of mass transfer. The idea is to make the conditions favorable for the component, A, in the liquid phase to transfer to the vapor phase. This involves a gas–liquid interface that A must cross. The total amount of A that has moved across this boundary can be defined as the flux of A, NA.
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The most used substrate is indium phosphide (InP). Other substrates like glass or ceramic can be applied for special applications. To facilitate nucleation, and to avoid tension in the grown layer the thermal expansion coefficient of substrate and grown layer should be similar. Centrifugal liquid-phase epitaxy is used commercially to make thin layers of silicon, germanium, and gallium arsenide.
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A common experimental way to observe the paramagnetism of dioxygen is to cool it down into the liquid phase. When poured between the poles of strong magnets that are close together the liquid oxygen can be suspended. Or a magnet can pull the stream of liquid oxygen as it is poured. Molecular orbital theory provides the explanation of these observations.
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Since these compounds are immiscible substrates, solid-liquid phase transfer catalysis (PTC) can be used, using quaternary ammonium bromide as a phase transfer catalyst. This is shown in the following reaction: :: 490x490px Besides these three examples, there are many more ways to synthesize cinnamyl acetate. The addition reaction of dinitrogen trioxide to cinnamyl acetate produces an intermediate in the synthesis of chloramphenicol.
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As of 1999, 7000 tonnes of synthetic and 100 tonnes of natural benzaldehyde were produced annually. Liquid phase chlorination and oxidation of toluene are the main routes. Numerous other methods have been developed, such as the partial oxidation of benzyl alcohol, alkali hydrolysis of benzal chloride, and the carbonylation of benzene.Brühne, Friedrich and Wright, Elaine (2002) “Benzaldehyde” in Ullmann's Encyclopedia of Industrial Chemistry.
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Thus, interactions between electron beam and gas together with interactions of gas (and its byproducts) with specimen usher a new area of research with as yet unknown consequences. Some of these may at first appear disadvantageous but later overcome, others may yield unexpected results. The liquid phase in the specimen with mobile radicals may yield a host of phenomena again advantageous or disadvantageous.
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The phase diagram on the right shows a positive azeotrope of hypothetical constituents, X and Y. The bottom trace illustrates the boiling temperature of various compositions. Below the bottom trace, only the liquid phase is in equilibrium. The top trace illustrates the vapor composition above the liquid at a given temperature. Above the top trace, only the vapor is in equilibrium.
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Low vapor pressure liquids such as ionic liquids can also be studied in open systems. LP-EM systems of both open and closed type have been developed for all three main types of electron microscopy, i.e., transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM), and scanning electron microscope (SEM). Instruments integrating liquid-phase SEM with light microscopy have also been developed.
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This phenomenon is also called evaporative cooling. This is why evaporating sweat cools the human body. Evaporation also tends to proceed more quickly with higher flow rates between the gaseous and liquid phase and in liquids with higher vapor pressure. For example, laundry on a clothes line will dry (by evaporation) more rapidly on a windy day than on a still day.
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Similar structures are found in deep water related to methane leakages. Significantly, gas hydrates can even be formed in the absence of a liquid phase. Under that situation, water is dissolved in gas or in liquid hydrocarbon phase. In 2017, both Japan and China announced that attempts at large-scale resource extraction of methane hydrates from under the seafloor were successful.
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This was for a device grown on a GaSb substrate by organometallic vapour phase epitaxy (OMVPE). Devices have been grown by molecular beam epitaxy (MBE) and liquid phase epitaxy (LPE). The internal quantum efficiencies (IQE) of these devices are approaching 90%, while devices grown by the other two techniques exceed 95%. The largest problem with InGaAsSb cells is phase separation.
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Wiener showed that the Wiener index number is closely correlated with the boiling points of alkane molecules. Later work on quantitative structure–activity relationships showed that it is also correlated with other quantities including the parameters of its critical point,. the density, surface tension, and viscosity of its liquid phase,. and the van der Waals surface area of the molecule..
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Perstraction is the separation technique developed from liquid-liquid extraction. Due to the presence of the membrane a wider selection of extractants can be used, this can include the use of miscible solutions, for example the recovery of ammonia from waste water using sulphuric acid. This process is analogous to pervaporation in some ways. But the permeate is in liquid phase.
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Wells, A. F. (1984) Structural Inorganic Chemistry, Oxford Press, Oxford, United Kingdom. . When aluminium trichloride is in its melted state, it exists as the dimer Al2Cl6, with tetracoordinate aluminium. This change in structure is related to the lower density of the liquid phase (1.78 g/cm3) versus solid aluminium trichloride (2.48 g/cm3). Al2Cl6 dimers are also found in the vapour phase.
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An illustration of a typical redox targeting flow battery Another approach is to pump the liquid phase only, leaving the solid active materials in the energy storage tanks. A research group reported redox targeting flow battery. There are redox targeting materials dissolved in the electrolyte and electrochemical reactions occur between the dissolved species. The solid materials are then been chemically oxidized or reduced.
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AFM of few-layer phosphorene sample continuously taken for 7 days. Phosphorene reacts with oxygen and water to develop liquid phase bubbles. One major disadvantage of phosphorene is its limited air-stability. Composed of hygroscopic phosphorus and with extremely high surface-to-volume ratio, phosphorene reacts with water vapor and oxygen assisted by visible light to degrade within the scope of hours.
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Crude acetone is hydrogenated in the liquid phase over Raney nickel or a mixture of copper and chromium oxide to give isopropyl alcohol. This process is useful, when it is coupled with excess acetone production. Mitsui & Co. developed additional step(s) to hydrogenating the acetone product and dehydrating the isopropanol product to propene, which is recycled as a starting reactant.
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Large-scale analysis of protein complexes is an emerging difficulty as methods for the fractionation of protein complexes that are not compatible with downstream proteomic techniques. The Systems Biology Initiative is utilising the technique of blue native continuous elution electrophoresis (BN-CEE). This method generates liquid-phase fractions of protein complexes. The resulting complexes can be further analysed by polyacrylamide gel electrophoresis and mass spectrometry.
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When they are removed from the magnetic field, there is no residual magnetism, which led to the development of magnetic separation technology. Other processes such as centrifugation, filtration, columns or precipitation, are not needed. Microbeads display a large surface area per volume. This together with uniformity of size and shape provides for very good accessibility and fast liquid-phase reaction kinetics, and rapid and efficient binding.
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The adsorption of gases and solutes is usually described through isotherms, that is, the amount of adsorbate on the adsorbent as a function of its pressure (if gas) or concentration (for liquid phase solutes) at constant temperature. The quantity adsorbed is nearly always normalized by the mass of the adsorbent to allow comparison of different materials. To date, 15 different isotherm models have been developed.
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A falling-film column (or wetted-wall column) is a particular chemical equipment used to achieve mass and heat transfer between two fluid phases (in general one gas phase and one liquid phase). It is essentially formed by a vertical tube-shaped vessel: the liquid stream flows through the inner wall of the tube and the gas stream flows in correspondence of the centre of the tube.
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Even powders with a liquid phase are amenable to this process and low pressures are possible, too. Among the disadvantages are the expense of a high-frequency generator and the need for proper alignment. If the mold is placed off centre, the heat distribution is uneven. But the main disadvantage is the dependence of the process on good inductive coupling and thermal conductivity of the mold.
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Using ethenolysis, higher molecular weight internal alkenes can be converted to more valuable terminal alkenes. The Shell higher olefin process (SHOP process) uses ethenolysis on an industrial scale. The SHOP α-olefin mixtures are separated by distillation, the higher molecular weight fractions are isomerized by alkaline alumina catalysts in the liquid phase. The resulting internal olefins are reacted with ethylene to regenerate α-olefins.
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Henry's law describes the tendency of a compound to join air in the vapor phase or dissolve in water. The Henry’s Law constant, sometimes called coefficient, is specific to each compound and depends on the system temperature. The constant is used to predict the amount of contaminant what will remain in the vapor phase (or transfer to the liquid phase), upon exiting the condenser.
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Inverted bucket and float traps are examples of mechanical traps. Float traps can have a mechanical linkage or can seal the trap through use of the float itself. # Thermostatic traps These remove condensate through the temperature difference of steam vs the liquid phase. The valve is driven through expansion and contraction of an element that is exposed to the heat from steam or condensate.
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The liquid that separates the flat faces between two polyhedral bubbles is called the lamellae; it is a continuous liquid phase. The areas where three lamellae meet are called plateau borders. When the bubbles in the foam are the same size the lamellae in the plateau borders meet at 120 degree angles. Since the lamella is slightly curved, the plateau region is at low pressure.
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The very high temperature (close to melting point) is also said to be related to another mechanism, interfacial sliding. Because at high temperatures, partial liquids appear in the matrix. The viscosity of the liquid plays the main role to accommodate the sliding of adjacent grain boundaries. The cavitation and stress concentration caused by the addition of second phase reinforcements are inhibited by the flow of liquid phase.
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The Dortmund Data Bank was founded in the 1970s at the University of Dortmund in Germany. The original reason for starting a vapor–liquid phase equilibria data collection was the developmentGmehling J., Weidlich U., "Die Dortmunder Datenbank. Basis für die Weiterentwicklung der UNIFAC-Methode", Chem.Ing.Tech., 57(5), 447-449, 1985 of the group contribution method UNIFAC which allows to estimate vapor pressures of mixtures.
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Sintering heats the powder to temperatures near the melting point in a protective atmosphere furnace to densify the particles using capillary forces in a process called sintering. MIM parts are often sintered at temperatures nearly high enough to induce partial melting in a process termed liquid phase sintering. For example, a stainless steel might be heated to . Diffusion rates are high leading to high shrinkage and densification.
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This creates a lot of demand for storage media. Solid-liquid phase change materials are usually encapsulated for installation in the end application, to contain in the liquid state. In some applications, especially when incorporation to textiles is required, phase change materials are micro-encapsulated. Micro-encapsulation allows the material to remain solid, in the form of small bubbles, when the PCM core has melted.
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He also conducted the research on the point of change in the liquid phase and worked on the experimental finding of light molecules. Einstein mentioned his work at the Berlin Academy of Science. In 1936 he checked the electric conductivity of liquid helium and started to organize the institute of low temperature at the Warsaw University of Technology. He also worked on the magnetocalorimetric of liquid helium.
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Liquid-phase epitaxy (LPE) is a method to grow semiconductor crystal layers from the melt on solid substrates. This happens at temperatures well below the melting point of the deposited semiconductor. The semiconductor is dissolved in the melt of another material. At conditions that are close to the equilibrium between dissolution and deposition, the deposition of the semiconductor crystal on the substrate is relatively fast and uniform.
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EME is closely related to liquid-phase microextraction (LPME) and provides high pre-concentration and efficient sample clean-up. In addition, because the extraction is performed under the influence of an electrical field, the extraction selectivity can be controlled by the direction and the magnitude of the electrical field.Astrid Gjelstad, Stig Pedersen-Bjergaard Electromembrane extraction – Three phase electrophoresis for future preparative applications Electrophoresis 35 (2014) 2421-2428.
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Another interesting though not unusual feature of the phase diagram is the point where the solid–liquid phase line meets the liquid–gas phase line. The intersection is referred to as the triple point. At the triple point, all three phases can coexist. Experimentally, the phase lines are relatively easy to map due to the interdependence of temperature and pressure that develops when multiple phases forms.
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The moving-belt interface (MBI) was developed in 1977. This interface consisted of an endless moving belt receiving the LC column effluent. On the belt, the solvent was evaporated by gently heating and efficiently exhausting the solvent vapors under reduced pressure in two vacuum chambers. After removing the liquid phase, the analytes would desorb from the belt and migrate to the MS ion source to be analysed.
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Phthalic anhydride was first reported in 1836 by Auguste Laurent. Early procedures involved liquid- phase mercury-catalyzed oxidation of naphthalene. The modern industrial variant process instead uses vanadium pentoxide (V2O5) as the catalyst in a gas-phase reaction with naphthalene using molecular oxygen. The overall process involves oxidative cleavage of one of the rings and loss of two of the carbon atoms as carbon dioxide.
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It readily substitutes for potassium in minerals, and is therefore fairly widespread. Rb has been used extensively in dating rocks; 87Rb beta decays to stable 87Sr. During fractional crystallization, Sr tends to concentrate in plagioclase, leaving Rb in the liquid phase. Hence, the Rb/Sr ratio in residual magma may increase over time, and the progressing differentiation results in rocks with elevated Rb/Sr ratios.
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The process is similar to the dye-diffusion approach: a graphic is printed onto a sheet of high-release paper and then transferred onto the chosen apparel using high heat and pressure. Heat converts the solid dye particles into a gas through sublimation. The liquid phase is skipped due to the instantaneity of the physical change. This immediacy bonds the released chemicals to the polyester fibers.
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While at Varian, Dr. Hyde and his colleagues extended the technique of electron nuclear double resonance (ENDOR), which had been introduced by G. Feher Feher, G., Observation of Nuclear Magnetic Resonances via the Electron Spin Resonance Line. Phys. Rev., 103:834-835, 1956 for the study of donors in silicon, to the liquid phase,Hyde, J. S., ENDOR of a free radical in solution.
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In liquid-phase reactions, carbon nanotubes were treated with oxidizing solutions of nitric acid or a combination of nitric and sulfuric acid to the same effect. However, overoxidation may occur causing the carbon nanotube to break up into fragments, which are known as carbonaceous fragments. Xing et al. revealed sonication assisted oxidation, with sulfuric and nitric acid, of carbon nanotubes and produced carbonyl and carboxyl groups.
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In physics, condensation typically refers to a gas-liquid phase transition. In biology the term 'condensation' is used much more broadly and can also refer to liquid-liquid phase separation to form colloidal emulsions or liquid crystals within cells, and liquid-solid phase separation to form gels, sols, or suspensions within cells as well as liquid-to-solid phase transitions such as DNA condensation during prophase of the cell cycle or protein condensation of crystallins in cataracts. With this in mind, the term 'biomolecular condensates' was deliberately introduced to reflect this breadth (see below). Since biomolecular condensation generally involves oligomeric or polymeric interactions between an indefinite number of components, it is generally considered distinct from formation of smaller stoichiometric protein complexes with defined numbers of subunits, such as viral capsids or the proteasome - although both are examples of spontaneous molecular self-assembly or self- organisation.
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Unfortunately, the handling of aluminium/iron powders poses major problems. Other substances that are especially reactive with atmospheric oxygen, such as titanium, are sinterable in special atmospheres or with temporary coatings. In powder metallurgy or ceramics it is possible to fabricate components which otherwise would decompose or disintegrate. All considerations of solid-liquid phase changes can be ignored, so powder processes are more flexible than casting, extrusion, or forging techniques.
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Phase diagram for a typical substance at a fixed volume. Vertical axis is Pressure, horizontal axis is Temperature. The green line marks the freezing point (above the green line is solid, below it is liquid) and the blue line the boiling point (above it is liquid and below it is gas). So, for example, at higher T, a higher P is necessary to maintain the substance in liquid phase.
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Side products were a wide range of carboxylic acids and oxidation products such as alcohols, aldehydes, esters, or ketones. The oxidation of paraffins was carried out in the liquid phase by molecular oxygen, e.g. by aerating with oxygen or atmospheric air, in the presence of catalysts such as permanganates, e.g. 0.1% - 0.3% potassium permanganate, at temperatures in the range of about 100 to 120 °C and under atmospheric pressure.
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Practical, user-applied hypersensitizing techniques have evolved over most of the last century and fall mostly into four types of treatments. Broadly, these involve liquid phase (washing), gas phase (out- gassing and baking and hydrogenation), exposure at lowered temperature, and pre-flashing. Some of these can be used in combination, but many severely shorten the shelf-life of a product and so can not be applied by the manufacturer.
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Synthetic membranes can be also categorized based on their structure (morphology). Three such types of synthetic membranes are commonly used in separation industry: dense membranes, porous membranes, and asymmetric membranes. Dense and porous membranes are distinct from each other based on the size of separated molecules. Dense membrane is usually a thin layer of dense material utilized in the separation processes of small molecules (usually in gas or liquid phase).
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When Laurdan is located in the cell membrane its emission maximum is centered at 440 nm in gel-phase, and at 490 nm in liquid-phase. This spectral shift is the result of the dipolar relaxation of Laurdan on the lipidic environment, namely, the reorientation of solvents caused by Laurdan’s excitation. Particularly, due to some water molecules located at the level of the glycerol backbone, where the naphthalene moiety residesT.
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Hydrogen- containing polar molecules like ethanol, ammonia, and water have powerful, intermolecular hydrogen bonds when in their liquid phase. These bonds provide another place where heat may be stored as potential energy of vibration, even at comparatively low temperatures. Hydrogen bonds account for the fact that liquid water stores nearly the theoretical limit of 3R per mole of atoms, even at relatively low temperatures (i.e. near the freezing point of water).
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Commercial systems typically use a bubble column reactor, where air is bubbled through a vertical column that is liquid full of the hot and pressurized wastewater. Fresh wastewater enters the bottom of the column and oxidized wastewater exits the top. The heat released during the oxidation is used to maintain the operating temperature. WAO is a liquid phase reaction using dissolved oxygen in water to oxidize wastewater contaminants.
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The final liquid phase allows minor adjustment to the viscosity of the finished product by addition of fats and emulsifiers, depending on the intended use of the chocolate. While most conches are batch-process machines, continuous-flow conches separate the stages with weirs, over which the product travels through separate parts of the machine. A continuous conche can reduce the conching time for milk chocolate to as little as four hours.
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Its structural and thermal stability (i.e., it does not decompose at high temperatures) allows its use under a wide range of reaction conditions. Additionally, the solubility of Raney nickel is negligible in most common laboratory solvents, with the exception of mineral acids such as hydrochloric acid, and its relatively high density (about 6.5 g cm−3) also facilitates its separation from a liquid phase after a reaction is completed.
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The decisive factor in such a classification of adsorption is merely temperature, irrespective of pressure. This is because a fluid cannot undergo a transition to a liquid phase at above-critical temperature, regardless of the pressure applied. This fundamental law determines the different adsorption mechanism for the subcritical and supercritical regions. For the subcritical region, the highest equilibrium pressure of adsorption is the saturation pressure P_{s} of adsorbate.
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These membranes are made of hydrophobic synthetic material (e.g. PTFE, PVDF or PP) and offer pores with a standard diameter between 0.1 and 0.5 µm. As water has strong dipole characteristics, whilst the membrane fabric is non-polar, the membrane material is not wetted by the liquid. Even though the pores are considerably larger than the molecules, the high water surface tension prevents the liquid phase from entering the pores.
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Thermochromic papers are used for thermal printers. One example is the paper impregnated with the solid mixture of a fluoran dye with octadecylphosphonic acid. This mixture is stable in solid phase; however, when the octadecylphosphonic acid is melted, the dye undergoes a chemical reaction in the liquid phase, and assumes the protonated colored form. This state is then conserved when the matrix solidifies again, if the cooling process is fast enough.
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An unusual feature of the water phase diagram is that the solid–liquid phase line (illustrated by the dotted green line) has a negative slope. For most substances, the slope is positive as exemplified by the dark green line. This unusual feature of water is related to ice having a lower density than liquid water. Increasing the pressure drives the water into the higher density phase, which causes melting.
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Generally, polycrystals cannot be superheated; they will melt promptly once they are brought to a high enough temperature. This is because grain boundaries are amorphous, and serve as nucleation points for the liquid phase. By contrast, if no solid nucleus is present as a liquid cools, it tends to become supercooled. Since this is undesirable for mechanical materials, alloy designers often take steps against it (by grain refinement).
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In this old practice, the production of gas has a positive effect in oil recovery by increasing the differential pressure driving the oil movement. Anaerobically produced methane from oil degradation have a low effect on MEOR due to its high solubility at high pressures. Carbon dioxide is also a good MEOR agent. The miscible CO2 is condensed into the liquid phase when light hydrocarbons are vaporised into the gas phase.
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Other historical names for it were kasumi-uchi (cloud metal), itame-gane (wood-grain metal), and yosefuki. The early components were relatively soft metals and alloys (gold, copper, silver, shakudō, shibuichi, and kuromido) which would form liquid phase diffusion bonds with one another without completely melting. This was useful in the traditional techniques of fusing and soldering the layers together. Over time, the practice of making mokume gane faded.
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In analytical chemistry, complexometric indicators are used in complexometric titration to indicate the exact moment when all the metal ions in the solution are sequestered by a chelating agent (most usually EDTA). Such indicators are also called metallochromic indicators. The indicator may be present in another liquid phase in equilibrium with the titrated phase, the indicator is described as extraction indicator. Some complexometric indicators are sensitive to air and are destroyed.
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Solvent extraction. Liquid–liquid extraction (LLE), also known as solvent extraction and partitioning, is a method to separate compounds or metal complexes, based on their relative solubilities in two different immiscible liquids, usually water (polar) and an organic solvent (non-polar). There is a net transfer of one or more species from one liquid into another liquid phase, generally from aqueous to organic. The transfer is driven by chemical potential, i.e.
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Acid-base, oxidation-reduction and specific adsorption characteristics are strongly dependent on the composition of the surface functional groups.Philippe Serp, José Luis Figueiredo, Carbon Materials for Catalysis, Wiley, – 2009, – 550 p. The surface of conventional activated carbon is reactive, capable of oxidation by atmospheric oxygen and oxygen plasma steam, and also carbon dioxide and ozone. Oxidation in the liquid phase is caused by a wide range of reagents (HNO3, H2O2, KMnO4).
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The liquid can be said to be saturated with thermal energy. Any addition of thermal energy results in a phase transition. If the pressure in a system remains constant (isobaric), a vapor at saturation temperature will begin to condense into its liquid phase as thermal energy (heat) is removed. Similarly, a liquid at saturation temperature and pressure will boil into its vapor phase as additional thermal energy is applied.
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Saturation pressure is the pressure for a corresponding saturation temperature at which a liquid boils into its vapor phase. Saturation pressure and saturation temperature have a direct relationship: as saturation pressure is increased, so is saturation temperature. If the temperature in a system remains constant (an isothermal system), vapor at saturation pressure and temperature will begin to condense into its liquid phase as the system pressure is increased.
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Ionic transfer is the transfer of ions from one liquid phase to another. This is related to the phase transfer catalysts which are a special type of liquid- liquid extraction which is used in synthetic chemistry. For instance nitrate anions can be transferred between water and nitrobenzene. One way to observe this is to use a cyclic voltammetry experiment where the liquid-liquid interface is the working electrode.
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Heterogeneous distillation means that during the distillation the liquid phase of the mixture is immiscible. In this case on the plates can be two liquid phases and the top vapour condensate splits in two liquid phases, which can be separated in a decanter. The simplest case of continuous heteroazeotropic distillation is the separation of a binary heterogeneous azeotropic mixture. In this case the system contains two columns and a decanter.
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Piezoelectricity is one of the key properties of electroceramics. E.G. Acheson heated a mixture of coke and clay in 1893, and invented carborundum, or synthetic silicon carbide. Henri Moissan also synthesized SiC and tungsten carbide in his electric arc furnace in Paris about the same time as Acheson. Karl Schröter used liquid-phase sintering to bond or "cement" Moissan's tungsten carbide particles with cobalt in 1923 in Germany.
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This means that generally the larger hailstones will form some distance from the stronger updraft where they can pass more time growing. As the hailstone grows it releases latent heat, which keeps its exterior in a liquid phase. Because it undergoes 'wet growth', the outer layer is sticky (i.e. more adhesive), so a single hailstone may grow by collision with other smaller hailstones, forming a larger entity with an irregular shape.
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Evaporation is a phase transition from the liquid phase to vapour (a state of substance below critical temperature) that occurs at temperatures below the boiling temperature at a given pressure. Evaporation occurs on the surface. Evaporation only occurs when the partial pressure of vapour of a substance is less than the equilibrium vapor pressure. For example, due to constantly decreasing pressures, vapor pumped out of a solution will eventually leave behind a cryogenic liquid.
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Boiling is also a phase transition from the liquid phase to gas phase, but boiling is the formation of vapor as bubbles of vapor below the surface of the liquid. Boiling occurs when the equilibrium vapor pressure of the substance is greater than or equal to the environmental pressure. The temperature at which boiling occurs is the boiling temperature, or boiling point. The boiling point varies with the pressure of the environment.
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One process for making nanoceramics varies is the sol-gel process, also known as chemical solution deposition. This involves a chemical solution, or the sol, made of nanoparticles in liquid phase and a precursor, usually a gel or polymer, made of molecules immersed in a solvent. The sol and gel are mixed to produce an oxide material which are generally a type of ceramic. The excess products (a liquid solvent) are evaporated.
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Some thickening agents are gelling agents (gellants), forming a gel, dissolving in the liquid phase as a colloid mixture that forms a weakly cohesive internal structure. Others act as mechanical thixotropic additives with discrete particles adhering or interlocking to resist strain. Thickening agents can also be used when a medical condition such as dysphagia causes difficulty in swallowing. Thickened liquids play a vital role in reducing risk of aspiration for dysphagia patients.
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The density of ice Ih is 0.917 g/cm3 which is less than that of liquid water. This is attributed to the presence of hydrogen bonds which causes atoms to become more distant in the solid phase. Because of this, ice Ih floats on water, which is highly unusual when compared to other materials. The solid phase of materials is usually more closely and neatly packed and has a higher density than the liquid phase.
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GaInAs is not a naturally- occurring material. Single crystal material is required for electronic and photonic device applications. Pearsall and co-workers were the first to describe single-crystal epitaxial growth of In0.53Ga0.47As on (111)-oriented and on (100)-oriented InP substrates. Single crystal material in thin-film form can be grown by epitaxy from the liquid-phase (LPE), vapour-phase (VPE), by molecular beam epitaxy (MBE), and by metalorganic chemical vapour deposition (MO-CVD).
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Hafnium disulfide is an inorganic compound of hafnium and sulfur. It is a layered dichalcogenide with the chemical formula is HfS2. A few atomic layers of this material can be exfoliated using the standard Scotch Tape technique (see graphene) and used for the fabrication of a field-effect transistor. High-yield synthesis of HfS2 has also been demonstrated using liquid phase exfoliation, resulting in the production of stable few-layer HfS2 flakes.
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However the technique can be used also in condensed matter (liquids and solids). In liquid phase, the carbocation is initially formed in the same solvation state as the parent molecule, and some reactions may happen before the solvent shells around it have time to rearrange. In a crystalline solid, the cation is formed in the same crystalline site; and the nature, position, and orientation of the other reagent(s) are strictly constrained.
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Strand is a 2009 Iranian experimental film directed by Rouzbeh Rashidi that tells the visual bond between nostalgia and physical reality, the liquid phase produced by the condensation of Stream of consciousness will evolve through the film and manifests itself using images and sounds. Strand is a personal journey in memory and time using human models, landscapes and cityscapes of Iran in order to explore the emotion hidden in past and future.
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A suspension is composed of a fine, particulate phase dispersed throughout a differing, heterogeneous phase. Shear-thickening behavior is observed in systems with a solid, particulate phase dispersed within a liquid phase. These solutions are different from a Colloid in that they are unstable; the solid particles in dispersion are sufficiently large for sedimentation, causing them to eventually settle. Whereas the solids dispersed within a colloid are smaller and will not settle.
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This morphology originates from the liquid-liquid phase separation during drying; solve evaporation causes the mixture to enter into the spinodal region, in which there are significant thermal fluctuations. Large domains prevent electrons from being collected efficiently (decreasing PCE). Small differences in polymer structure can also lead to significant changes in crystal packing that inevitably affect device morphology. PCPDTBT differs from PSBTBT caused by the difference in bridging atom between the two polymers (C vs.
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Multiple emulsions are also possible, including a "water-in-oil-in-water" emulsion and an "oil-in-water- in-oil" emulsion. Emulsions, being liquids, do not exhibit a static internal structure. The droplets dispersed in the continuous phase (sometimes referred to as the “dispersion medium”) are usually assumed to be statistically distributed to produce roughly spherical droplets. When molecules are ordered during liquid-liquid phase separation, they form liquid crystals rather than emulsions.
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This method can be affected by changes in the system pressure and gas velocity. Advanced signal processing is used where a liquid phase has an effect on the measurement signal such as pressure fluctuations in a DP flow meter or shift in the speed of sound in ultrasonic flow meter. Complex analysis and modelling of these signals can determine the liquid and gas flows. There are a number of commercially available wet gas flow meters.
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Modern neutron diffractometers have the capability to measure complete scattering spectra in a couple of minutes, as the temperature is ramped, enabling cryoporometry experiments to be performed. ND cryoporometry has the unique distinction of being able to monitor as a function of temperature the quantity of different crystalline phases (such as hexagonal ice and cubic ice) as well as the liquid phase, and thus can give pore-phase structural information as a function of temperature.
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Electrospray ionization is also utilized in studying noncovalent gas phase interactions. The electrospray process is thought to be capable of transferring liquid-phase noncovalent complexes into the gas phase without disrupting the noncovalent interaction. Problems such as non specific interactions have been identified when studying ligand substrate complexes by ESI-MS or nanoESI-MS. An interesting example of this is studying the interactions between enzymes and drugs which are inhibitors of the enzyme.
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As the water table around the well is lowered from pumping, unsaturated soil is exposed. This area, called the capillary fringe, is often highly contaminated, as it holds undissolved chemicals, chemicals that are lighter than water, and vapors that have escaped from the dissolved groundwater below. Contaminants in the newly exposed zone can be removed by vapor extraction. Once above ground, the extracted vapors and liquid-phase organics and groundwater are separated and treated.
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However, because Rb substitutes for K in minerals and these minerals have different K/Ca ratios, the minerals will have had different Rb/Sr ratios. During fractional crystallization, Sr tends to become concentrated in plagioclase, leaving Rb in the liquid phase. Hence, the Rb/Sr ratio in residual magma may increase over time, resulting in rocks with increasing Rb/Sr ratios with increasing differentiation. Highest ratios (10 or higher) occur in pegmatites.
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This is evidence that the adhesive forces between different components are stronger than the average cohesive forces between like components. In consequence each component is retained in the liquid phase by attractive forces that are stronger than in the pure liquid so that its partial vapor pressure is lower. For example, the system of chloroform (CHCl3) and acetone (CH3COCH3) has a negative deviationP. Atkins and J. de Paula, Physical Chemistry (8th ed.
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Particle agglomeration refers to formation of assemblages in a suspension and represents a mechanism leading to the functional destabilization of colloidal systems. During this process, particles dispersed in the liquid phase stick to each other, and spontaneously form irregular particle assemblates, flocs, or agglomerates. This phenomenon is also referred to as coagulation or flocculation and such a suspension is also called unstable. Particle agglomeration can be induced by adding salts or other chemicals referred to as coagulant or flocculant.
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Saffron is used in the confectionery and liquor industries; this is its most common use in Italy. Chartreuse, izarra, and strega are types of alcoholic beverages that rely on saffron to provide a flourish of colour and flavour. Saffron threads are often crumbled and pre-soaked in water or sherry for several minutes prior to adding them to a dish. This process extracts the threads' colour and flavour into the liquid phase; powdered saffron does not require this step.
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If CO2 were to be injected to the ocean bottom, the pressures would be great enough for CO2 to be in its liquid phase. The idea behind ocean injection would be to have stable, stationary pools of CO2 at the ocean floor. The ocean could potentially hold over a thousand billion tons of CO2. However, this avenue of sequestration isn't being as actively pursued because of concerns about the impact on ocean life, and concerns about its stability.
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Frandsen was born in the parish of Sønder Lem in the town of Ringkøbing in Ringkøbing-Skjern, Midtjylland, Denmark. He emigrated from Denmark to the United States in 1921. Frandsen earned his Ph.D. in Physical Chemistry from the University of California in 1926. In 1928, Frandsen invented the Liquid Phase Cracking Process, discovering that when oil is heated to a point at which cracking (chemistry) takes place, the heat consumed causes the oil temperature to decrease.
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His areas of research are quantum mechanics, statistical physics, condensed matter theory, high energy physics, general relativity, turbulence theory, theory of liquids and glasses. He is best known for his pioneering and fundamental contributions to the modern theory of phase transitions in collaboration with Valery Pokrovsky, as well as the collective tube model in the theory of hadron-nuclei collisions at high energies, applications of the pattern recognition theory to local structure in liquids, and liquid-liquid phase transitions.
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Among her many contributions include manufacturing China's first monocrystalline silicon, and the first mono-crystal furnace used to extract silicon in China. She laid the foundation of development in microelectronics and optoelectronics. She was responsible for developing extensive materials in a high-purified vapor phase and liquid phase and led China to become the world leader. She was honored as Academician of Chinese Academy of Sciences and became the vice president of China Association for Science and Technology.
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The mPower reactor control rods are inserted from the top of the core and insert upon scram under gravity. All of the primary coolant was in the liquid phase during normal operation. The integral once-through steam generator was an advanced derivative of the steam generators used in older B&W; designs (Davis Besse). Control rod drives do not penetrate the IRV, as in the light water reactors of today, but are instead wholly enclosed within the IRV.
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A key feature of this interface is to produce top quality EI spectra from compounds dissolved in a liquid phase. In this case, quality is intended as a measure of the degree of success in a virtual comparison with thousands of spectra stored in the electronic libraries. Identification capability in real- world applications, when peaks are small and noise is high, can be greatly influenced by the quality of ionization. A NIST library version 2.0d was used for comparison.
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The trichloride is prepared by dissolving in hydrochloric acid: : + 6 HCl → 2 + 3 Structure of gaseous SbF5 The pentahalides and have trigonal bipyramidal molecular geometry in the gas phase, but in the liquid phase, is polymeric, whereas is monomeric. is a powerful Lewis acid used to make the superacid fluoroantimonic acid ("H2SbF7"). Oxyhalides are more common for antimony than for arsenic and phosphorus. Antimony trioxide dissolves in concentrated acid to form oxoantimonyl compounds such as SbOCl and .
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Phase diagram of a negative azeotrope. Vertical axis is temperature, horizontal axis is composition. The phase diagram on the right shows a negative azeotrope of ideal constituents, X and Y. Again the bottom trace illustrates the boiling temperature at various compositions, and again, below the bottom trace the mixture must be entirely liquid phase. The top trace again illustrates the condensation temperature of various compositions, and again, above the top trace the mixture must be entirely vapor phase.
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Ether holds the last bit of water so tenaciously that only a very powerful desiccant such as sodium metal added to the liquid phase can result in completely dry ether.Cohen, Julius B. Practical Organic Chemistry MacMillan 1930 Anhydrous calcium chloride is used as a desiccant for drying a wide variety of solvents since it is inexpensive and does not react with most nonaqueous solvents. Chloroform is an example of a solvent that can be effectively dried using calcium chloride.
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The Pellizzari reaction is limited in the number of substituents that can be on the ring, so other methods have been developed to incorporate three elements of diversity. Liquid-phase synthesis of 3-alkylamino-4,5-disubstituted-1,2,4-triazoles by PEG support has given moderate yields with excellent purity. In practice, the Pellizzari reaction requires high temperatures, long reaction times, and has an overall low yield. However, adding microwave irradiation shortens the reaction time and increases its yield.
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The quantitatively described steam quality (steam dryness) is the proportion of saturated steam in a saturated water/steam mixture. In other words, a steam quality of 0 indicates 100% water while a steam quality of 1 (or 100%) indicates 100% steam. The quality of steam on which steam whistles are blown is variable and may affect frequency. Steam quality determines the velocity of sound, which declines with decreasing dryness due to the inertia of the liquid phase.
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That is to say it will assume a solid phase at the temperature of the carrier and liquid phase at some higher temperature. The range of commercially available ink compositions which could meet the requirement of the invention are not know at the present time. However, satisfactory printing according to the invention has been achieved with a conductive metal alloy as ink. It is extremely hard at room temperature and adheres well to the surface of the carrier.
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An emulsion is a mixture of two or more liquids that are normally immiscible (unmixable or unblendable) owing to liquid-liquid phase separation. Emulsions are part of a more general class of two-phase systems of matter called colloids. Although the terms colloid and emulsion are sometimes used interchangeably, emulsion should be used when both phases, dispersed and continuous, are liquids. In an emulsion, one liquid (the dispersed phase) is dispersed in the other (the continuous phase).
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Simple sublimation apparatus. Water usually cold, is circulated in cold finger to allow the desired compound to be deposited. 1 Cooling water in 2 Cooling water out 3 Vacuum/gas line 4 Sublimation chamber 5 Sublimed compound 6 Crude material 7 External heating Sublimation apparatus is equipment, commonly laboratory glassware, for purification of compounds by selective sublimation. In principle, the operation resembles purification by distillation, except that the products do not pass through a liquid phase.
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In solid acetic acid, the molecules form chains, individual molecules being interconnected by hydrogen bonds. In the vapour at , dimers can be detected. Dimers also occur in the liquid phase in dilute solutions in non-hydrogen-bonding solvents, and a certain extent in pure acetic acid, but are disrupted by hydrogen-bonding solvents. The dissociation enthalpy of the dimer is estimated at 65.0–66.0 kJ/mol, and the dissociation entropy at 154–157 J mol−1 K−1.
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In addition to polymer separators, there are several other types of separators. There are nonwovens, which consist of a manufactured sheet, web, or mat of directionally or randomly oriented fibers. Supported liquid membranes, which consist of a solid and liquid phase contained within a microporous separator. Additionally there are also polymer electrolytes which can form complexes with different types of alkali metal salts, which results in the production of ionic conductors which serve as solid electrolytes.
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Eventually after solvent removal, the polymer-rich phase solidifies to form the matrix and the polymer- lean phase develops into pores. Next, two types of phase separation can be carried out on the polymer solution depending on the desired pattern. Liquid- liquid separation is usually used to form bicontinuous phase structures while solid-liquid phase separation is used to form crystal structures. The gelation step plays a crucial role in controlling the porous morphology of the nanofibrous matrices.
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It was recognized that there was an opportunity, particularly afforded by the use of liquid phase epitaxy using aluminum gallium arsenide, to introduce heterojunctions. Heterostructures consist of layers of semiconductor crystal having varying bandgap and refractive index. Heterojunctions (formed from heterostructures) had been recognized by Herbert Kroemer, while working at RCA Laboratories in the mid-1950s, as having unique advantages for several types of electronic and optoelectronic devices including diode lasers. LPE afforded the technology of making heterojunction diode lasers.
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170px Graphene is chemically dormant, mechanically sturdy, and non-permeable to gas or liquid. So, carbon plays a major role for fabrication of nanomaterials with porous nature. Graphene membranes that are formed by graphene oxide molecules or chemically converted graphene that is adhered with 2D nano mediated arrays have the ability to efficiently separate molecules in a gas or in a liquid phase. Graphene-coated nanomembranes are said to be more applicable in water treatment due to its unique properties.
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Fe - Cr Phase diagram To qualify as stainless steel, Fe-base alloys must contain at least 10.5%Cr. The Iron-Chromium phase diagram shows that up to about 13%Cr, the steel undergoes successive transformations upon cooling from the liquid phase from ferritic α phase to austenitic γ phase and back to α. When some carbon is present, and if cooling occurs quickly, some of the austenite will transform into martensite.Tempering/annealing will transform the martensitic structure into ferrite and carbides.
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Purely amorphous tantalum pentoxide has a similar local structure to the crystalline polymorphs, built from TaO6 and TaO7 polyhedra, while the molten liquid phase has a distinct structure based on lower coordination polyhedra, mainly TaO5 and TaO6. The difficulty in forming material with a uniform structure has led to variations in its reported properties. Like many metal oxides Ta2O5 is an insulator and its band gap has variously been reported as being between 3.8 and 5.3 eV, depending on the method of manufacture.
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VOF scheme was proposed by Hirt and Nichols in 1981. In this method, fraction of the cell occupied by the liquid phase can be calculated by solving the transport equation.Hirt, C.W.; Nichols, B.D. (1981), Volume of fluid (VOF) method for the dynamics of free boundaries, Journal of Computational Physics 39 (1): 201–225, , The transport equation is: : \+ div(cv) = 0 where c is the fraction of control volume filled. c=1 for completely filled and c = 0 for completely empty control volumes.
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These additives react with impurities to form a transient liquid phase and promote sintering of the diboride composites. The addition of rare earth oxides such as Y2O3, Yb2O3, La2O3 and Nd2O3 can lower densification temperatures and can react with surface oxides to promote densification. Hot pressing may result in improved densities for UHTCs, but it is an expensive technique that relies on high temperatures and pressures to provide useful materials. Pressureless sintering is another method for processing and densifying UHTCs.
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In the presence of two phases ( and ), the surface (surface phase) is located in between the phase and phase . Experimentally, it is difficult to determine the exact structure of an inhomogeneous surface phase that is in contact with a bulk liquid phase containing more than one solute. Inhomogeneity of the surface phase is a result of variation of mole ratios. A model proposed by Josiah Willard Gibbs proposed that the surface phase as an idealized model that had zero thickness.
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2,6-Dimethylnaphthalene is mainly used for the preparation of 2,6-naphthalenedicarboxylic acid by oxidation of 2,6-dimethylnaphthalene in the liquid phase. 2,6-Naphthalenedicarboxylic acid is a monomer for the production of high-performance polymers, in particular poly (ethylene-2,6-naphthalene dicarboxylate) or shorter polyethylene naphthalate (PEN), a polyester which is stronger and has a higher thermal resistance than the frequently used polyethylene terephthalate (PET). However, 2,6-DMN is a more expensive intermediate than terephthalic acid that is used for PET.
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In order to study the reactions of particles in gaseous environments, a STEM may be modified with a differentially pumped sample chamber to allow gas flow around the sample, whilst a specialized holder is used to control the reaction temperature. Alternatively a holder mounted with an enclosed gas flow cell may be used. Nanoparticles and biological cells have been studied in liquid environments using liquid-phase electron microscopy in STEM, accomplished by mounting a microfluidic enclosure in the specimen holder.
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Hydrogen gas porosity is an aluminium casting defect in the form of a porosity or void in an aluminium casting caused by a high level of hydrogen gas (H2) dissolved in the aluminium at liquid phase. The solubility of hydrogen in solid aluminium is much smaller than in liquid aluminium. As the aluminium freezes, some of the hydrogen comes out of solution and forms bubbles, creating porosity in the solid aluminium. Aluminium foundries want to produce high-quality aluminum castings with minimum porosity.
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Within the Earth's atmosphere and surface, the liquid phase is the most common and is the form that is generally denoted by the word "water". The solid phase of water is known as ice and commonly takes the structure of hard, amalgamated crystals, such as ice cubes, or loosely accumulated granular crystals, like snow. Aside from common hexagonal crystalline ice, other crystalline and amorphous phases of ice are known. The gaseous phase of water is known as water vapor (or steam).
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In DMLS, powder bed supports the parts and keep them held in place. However, support structures are explicitly required for most of the downward facing surfaces that make an angle less than 45 degrees with the powder bed. This is because powder bed alone is not sufficient enough to hold the liquid phase of the metal that is created when laser is scanning the powder. Support structures are also required to restrict curling/warping of the melted powder due to high- temperature gradients.
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In polycrystalline media or frozen solution, ENDOR can provide spatial relationships between the coupled nuclei and electron spins. This is possible in solid phases where the EPR spectrum arises from the observance of all orientations of paramagnetic species; as such the EPR spectrum is dominated by large anisotropic interactions. This is not so in liquid phase samples where spatial relationships are not possible. Such spatial arrangements require that the ENDOR spectra are recorded at different magnetic field settings within the EPR powder pattern.
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Silicon nanowires, also referred to as SiNWs, are a type of semiconductor nanowire most often formed from a silicon precursor by etching of a solid or through catalyzed growth from a vapor or liquid phase. Such nanowires have promising applications in lithium ion batteries, thermoelectrics and sensors. Initial synthesis of SiNWs is often accompanied by thermal oxidation steps to yield structures of accurately tailored size and morphology. SiNWs have unique properties that are not seen in bulk (three-dimensional) silicon materials.
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The volatile compounds are drawn along a heated line onto a 'trap'. The trap is a column of adsorbent material at ambient temperature that holds the compounds by returning them to the liquid phase. The trap is then heated and the sample compounds are introduced to the GC-MS column via a volatiles interface, which is a split inlet system. P&T; GC-MS is particularly suited to volatile organic compounds (VOCs) and BTEX compounds (aromatic compounds associated with petroleum).
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Left to equilibration, many compositions will form a uniform single phase, but depending on the temperature and pressure even a single substance may separate into two or more distinct phases. Within each phase, the properties are uniform but between the two phases properties differ. Water in a closed jar with an air space over it forms a two phase system. Most of the water is in the liquid phase, where it is held by the mutual attraction of water molecules.
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The liquid nucleation and growth model (LNG) treats nanoparticle melting as a surface initiated process. The surface melts initially, and the liquid-solid interface quickly advances through the entire nanoparticle. The LNG defines melting conditions through the Gibbs-Duhem relations, yielding a melting temperature function dependent on the interfacial energies between the solid and liquid phases, volumes and surface areas of each phase, and size of the nanoparticle. The model calculations show that the liquid phase forms at lower temperatures for smaller nanoparticles.
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There are two stages in the liquid crystals: #the hot nematic stage is the closest to the liquid phase where the molecules are freely moving around and only partly ordered. #the cold smectic stage is closest to a solid phase where the molecules align themselves into tightly wound chiral matrixes. Liquid crystal thermometers portray temperatures as colors and can be used to follow temperature changes caused by heat flow. They can be used to observe that heat flows by conduction, convection, and radiation.
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The dilution of the dye in the liquid phase is used to calculate the liquid flow rate. This technique can be rather difficult to apply as it can be difficult gaining access to the correct points needed to conduct this test. Microwave technology utilises the higher permittivity of water than hydrocarbons to detect the overall water fraction in the liquid and gas phases. As it only detects and measures the water component, the liquid hydrocarbon component must be measured by another method.
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The interface between a liquid phase technique (HPLC) with a continuously flowing eluate, and a gas phase technique carried out in a vacuum was difficult for a long time. The advent of electrospray ionization changed this. Currently, the most common LC-MS interfaces are electrospray ionization (ESI), atmospheric pressure chemical ionization (APCI), and atmospheric pressure photo-ionization (APPI). These are newer MS ion sources that facilitate the transition from a high pressure environment (HPLC) to high vacuum conditions needed at the MS analyzer.
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The frost point is similar to the dew point in that it is the temperature to which a given parcel of humid air must be cooled, at constant atmospheric pressure, for water vapor to be deposited on a surface as ice crystals without undergoing the liquid phase (compare with sublimation). The frost point for a given parcel of air is always higher than the dew point, as the stronger bonding between water molecules on the surface of ice requires higher temperature to break.
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The applied electric field prevents recombination of all the electrons produced from a charged particle interaction in the TPC. These electrons are drifted to the top of the liquid phase by the electric field. The ionization is then extracted into the gas phase by the stronger electric field in the gaseous phase. The electric field accelerates the electrons to the point that it creates a proportional scintillation signal that is also collected by the PMTs, and is referred to as the S2 signal.
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Continuing at Illinois he did his PhD research under the direction of Nick Holonyak, writing a thesis on room temperature visible semiconductor diode lasers. He received his PhD from Illinois in 1975. Coleman joined Bell Labs, Murray Hill in 1976, where his initial assignment was in the Materials Science Research Department under the direction of Morton B. Panish. His work there involved contributions to the development of 1.3 μm InGaAsP CW room temperature diode telecommunications lasers grown by liquid phase epitaxy (LPE).
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Typical countercurrent-flow spray tower. A spray tower (or spray column or spray chamber) is gas-liquid contactor used to achieve mass and heat transfer between a continuous gas phase (that can contain dispersed solid particles) and a dispersed liquid phase. It consists of an empty cylindrical vessel made of steel or plastic, and nozzles that spray liquid into the vessel. The inlet gas stream usually enters at the bottom of the tower and moves upward, while the liquid is sprayed downward from one or more levels.
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Immuno-RCA is an isothermal signal amplification method for high-specificity & high- sensitivity protein detection and quantification. This technique combines two fields: RCA, which allows nucleotide amplification, and immunoassay, which uses antibodies specific to intracellular or free biomarkers. As a result, immuno-RCA gives a specific amplified signal (high signal-to-noise ratio), making it suitable for detecting, quantifying and visualizing low abundance proteic markers in liquid-phase immunoassays and immunohistochemistry. Immuno- RCA follows a typical immuno-absorbent reaction in ELISA or immunohistochemistry tissue staining.
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An example of a mass independent process is the fractionation of oxygen atoms in ozone. This is due to the kinetic isotope effect (KIE) and is caused by different isotope molecules reacting at different speeds. An example of a mass dependent process is the fractionation of water as it transitions from the liquid to gas phase. Water molecules with heavier isotopes (18O and 2H) tend to stay in the liquid phase as water molecules with lighter isotopes (16O and 1H) preferentially move to the gas phase.
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Rather than using a single liquid phase, it is also possible to use two liquid phases in order to generate droplets. The most common method for generating droplets includes the flow of an aqueous stream perpendicular to an oil stream. When these two streams meet at a T-junction, uniform, aqueous droplets are formed that are surrounded by an oil phase. Depending upon the geometry of the microfluidic device as well as the flow rates used, droplets can also be formed using a flow focusing device.
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The production process chosen was one consisting of liquid fermentation followed by a solid substrate phase. During the liquid phase, the fungus biomass is bulked up in a solution of sugar and yeast and may produce submerged conidia.Jenkins, N.E., Prior, C., 1993, Growth and formation of true conidia by Metarhizium flavoviride in a simple liquid medium, Mycological Research, 97(12), 1489–1494 Subsequently, the resulting broth is used to inoculate partially boiled and sterilised rice. The fungal mycelium invades the rice and then starts to sporulate.
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Long-range order has been observed in thin films of colloidal liquids under oil—with the faceted edge of an emerging single crystal in alignment with the diffuse streaking pattern in the liquid phase. Structural defects have been directly observed in the ordered solid phase as well as at the interface of the solid and liquid phases. Mobile lattice defects have been observed via Bragg reflections, due to the modulation of the light waves in the strain field of the defect and its stored elastic strain energy.
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The best crystals are obtained from the liquid phase, but the growth is impracticably slow – several months for a 5–10 mm crystal. Growth from the vapor phase is a reasonable compromise in terms of speed and quality. Adamantane is sublimed in a quartz tube placed in a furnace, which is equipped with several heaters maintaining a certain temperature gradient (about 10 °C/cm for adamantane) along the tube. Crystallization starts at one end of the tube, which is kept near the freezing point of adamantane.
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In cases where greater resolving power is required, two-dimensional chromatography (GCxGC) can be applied. High performance liquid chromatography (HPLC) has emerged as the most common separation technique for metabolomic analysis. With the advent of electrospray ionization, HPLC was coupled to MS. In contrast with GC, HPLC has lower chromatographic resolution, but requires no derivatization for polar molecules, and separates molecules in the liquid phase. Additionally HPLC has the advantage that a much wider range of analytes can be measured with a higher sensitivity than GC methods.
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This method is designed to be robust where the other methods don't even provide any results in particular. As such, it is indispensable, since it is the only way to use the sessile drop technique on very high surface energy solids. Its major drawback is the fact that it is far more complex, both in its mathematics and experimentally. The Schultz theory requires one to account for many more factors, as there is now the unusual interaction of the probe liquid phase with the surrounding liquid .
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In DCMD, both sides of the membrane are charged with liquid- hot feed water on the evaporator side and cooled permeate on the permeate side. The condensation of the vapour passing through the membrane happens directly inside the liquid phase at the membrane boundary surface. Since the membrane is the only barrier blocking the mass transport, relatively high surface related permeate flows can be achieved with DCMD. A disadvantage is the high sensible heat loss, as the insulating properties of the single membrane layer are low.
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Collision in diluted gas or liquid solution is regulated by diffusion instead of direct collisions, which can be calculated from Fick's laws of diffusion. For a diluted solution in the gas or the liquid phase, the above equation is not suitable when diffusion takes control of the collision frequency, i.e., The direct collision between the two molecules no longer dominates. For any given molecule A, it has to collide with a lot of solvent molecules, let's say molecule C, before finding the B molecule to react with.
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In this landmark equation a is called the attraction parameter and b the repulsion parameter or the effective molecular volume. While the equation is definitely superior to the ideal gas law and does predict the formation of a liquid phase, the agreement with experimental data is limited for conditions where the liquid forms. While the van der Waals equation is commonly referenced in text-books and papers for historical reasons, it is now obsolete. Other modern equations of only slightly greater complexity are much more accurate.
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A unique class of partially crystalline aromatic polyesters based on p-hydroxybenzoic acid and related monomers, liquid-crystal polymers are capable of forming regions of highly ordered structure while in the liquid phase. However, the degree of order is somewhat less than that of a regular solid crystal. Typically, LCPs have a high mechanical strength at high temperatures, extreme chemical resistance, inherent flame retardancy, and good weatherability. Liquid-crystal polymers come in a variety of forms from sinterable high temperature to injection moldable compounds.
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During the 1930s, Frenkel and Ioffe opposed dangerous tendencies in Soviet physics, binding science and materialist ideology, which shows their remarkable courage. Soviet physics as a result of these actions never spun down as much as biology. Still, he afterwards forwent publishing several papers, fearing it will lead to some unfortunate consequences. Yakov Frenkel was involved in the studies of liquid phase, too, – since mid 1930s (he undertook some research in colloids) and during the World War II, when the institute was evacuated to Kazan.
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SEM-Picture of PMMA-particles fabricated by dispersion polymerization after drying / removal of the organic liquid phase (cyclohexane) At the onset of polymerization, polymers remain in solution until they reach a critical molecular weight (MW), at which point they precipitate. These initial polymer particles are unstable and coagulate with other particles until stabilized particles form. After this point in the polymerization, growth only occurs by addition of monomer to the stabilized particles. As the polymer particles grow, stabilizer (or dispersant) molecules attach covalently to the surface.
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Oxidation of organics to CO is most commonly achieved in liquid solutions by the creation of the highly oxidizing chemical species, the hydroxyl radical (OH•). Organic oxidation in a combustion environment involves the creation of other energized molecular oxygen species. For the typical TOC levels in UPW systems most methods utilize hydroxyl radicals in the liquid phase. There are multiple methods to create sufficient concentrations of hydroxyl radicals needed to completely oxidize the organics in water to CO, each method being appropriate for different water purity levels.
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When the green powder is brought into water a yellow/orange solution is obtained from left over ammonium dichromate. Observations obtained using relatively high magnification microscopy during a kinetic study of the thermal decomposition of ammonium dichromate provided evidence that salt breakdown proceeds with the intervention of an intermediate liquid phase rather than a solid phase. The characteristic darkening of crystals as a consequence of the onset of decomposition can be ascribed to the dissociative loss of ammonia accompanied by progressive anion condensation to , , etc., ultimately yielding .
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It is equivalent to surface area of carbon between 900 and 1100 m2/g. It is the standard measure for liquid-phase applications. Iodine number is defined as the milligrams of iodine adsorbed by one gram of carbon when the iodine concentration in the residual filtrate is at a concentration of 0.02 normal (i.e. 0.02N). Basically, iodine number is a measure of the iodine adsorbed in the pores and, as such, is an indication of the pore volume available in the activated carbon of interest.
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Through the formation of a large number of basic and acidic groups on the surface of oxidized carbon to sorption and other properties can differ significantly from the unmodified forms. Activated carbon can be nitrogenated by natural products or polymers or processing of carbon with nitrogenating reagents. Activated carbon can interact with chlorine, bromine and fluorine. Surface of activated carbon, like other carbon materials can be fluoralkylated by treatment with (per)fluoropolyether peroxide in a liquid phase, or with wide range of fluoroorganic substances by CVD-method.
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Nanoelectrospray ionization consumes only a few microliters of a sample and forms smaller droplets. Operation at low pressure was particularly effective for low flow rates where the smaller electrospray droplet size allowed effective desolvation and ion formation to be achieved. As a result, the researchers were later able to demonstrate achieving an excess of 50% overall ionization utilization efficiency for transfer of ions from the liquid phase, into the gas phase as ions, and through the dual ion funnel interface to the mass spectrometer.
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Prof. Maroncelli's research interests include solvation and solvent effects on chemical reaction, liquid- phase dynamics, electron and proton transfer reactions, supercritical fluids and expanded liquids, ionic liquids, ultrafast spectroscopy, and computer simulation. Maroncelli’s research seeks to develop a fundamental understanding of the molecular nature of solvation and how it affects chemical reactions taking place in solution. Solvation involves the interactions between dissolved molecules (solutes) and molecules of the solvent. Favorable arrangements of solvent molecules around the solute lower its energy, which leads to dissolution.
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Amorphous brazing foils are compositionally much more uniform even after crystallization, they melt over a narrow temperature range under transient heating. This is a consequence of the shorter distances over which atoms of different elements have to diffuse in order to form a uniform liquid phase. The resulting instant melting and their superior flow characteristic is only one of the important features of ABFs. The absence of the residual organic solvent bases evident in powder paste/tapes correspondingly eliminates soot formation and furnace fouling.
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Systems that have vapor pressures higher than indicated by the above formula are said to have positive deviations. Such a deviation suggests weaker intermolecular attraction than in the pure components, so that the molecules can be thought of as being "held in" the liquid phase less strongly than in the pure liquid. An example is the azeotrope of approximately 95% ethanol and water. Because the azeotrope's vapor pressure is higher than predicted by Raoult's law, it boils at a temperature below that of either pure component.
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The point of melting is indicated by the darkening of the hole when the liquid phase appears, destroying the black body conditions. Today, containerless laser heating techniques, combined with fast pyrometers and spectro- pyrometers, are employed to allow for precise control of the time for which the sample is kept at extreme temperatures. Such experiments of sub-second duration address several of the challenges associated with more traditional melting point measurements made at very high temperatures, such as sample vaporization and reaction with the container.
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Jameson worked on NMR in the gas and liquid phase to establish inter and intra-molecular effects on NMR parameters. She looked at how isotopic substitution impacted the chemical shift of NMR, and used rotational–vibrational averaging theory to explain intramolecular effects, such as isotope effects and the temperature dependence of shifts in NMR. She used gas phase NMR to extract relaxation times that allowed calculation of effective collision cross-sections. She described how NMR shifts could be used as a paradigm for electronic properties of molecules.
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For example, if the constituents are X and Y, then X sticks to Y with roughly equal energy as X does with X and Y does with Y. A so-called positive deviation from Raoult's law results when the constituents have a disaffinity for each other – that is X sticks to X and Y to Y better than X sticks to Y. Because this results in the mixture having less total affinity of the molecules than the pure constituents, they more readily escape from the stuck-together phase, which is to say the liquid phase, and into the vapor phase. When X sticks to Y more aggressively than X does to X and Y does to Y, the result is a negative deviation from Raoult's law. In this case because the molecules in the mixture are sticking together more than in the pure constituents, they are more reluctant to escape the stuck-together liquid phase. When the deviation is great enough to cause a maximum or minimum in the vapor pressure versus composition function, it is a mathematical consequence that at that point, the vapor will have the same composition as the liquid, resulting in an azeotrope.
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Electrochemistry is the study of processes driven through an applied potential at a solid-liquid or liquid-liquid interface. The behavior of an electrode-electrolyte interface is affected by the distribution of ions in the liquid phase next to the interface forming the electrical double layer. Adsorption and desorption events can be studied at atomically flat single crystal surfaces as a function of applied potential, time, and solution conditions using spectroscopy, scanning probe microscopy and surface X-ray scattering. These studies link traditional electrochemical techniques such as cyclic voltammetry to direct observations of interfacial processes.
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Tie line in the Alpha plus Liquid two phase region There is now more than one two-phase region. The tie line drawn is from the solid alpha to the liquid and by dropping a vertical line down at these points the mass fraction of each phase is directly read off the graph, that is the mass fraction in the x axis element. The same equations can be used to find the mass fraction of alloy in each of the phases, i.e. wl is the mass fraction of the whole sample in the liquid phase.
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Reactive multi-layer foils are a class of reactive materials, sometimes referred to as a pyrotechnic initiator of two mutually reactive metals, sputtered to form thin layers that create a laminated foil. On initiation by a heat pulse, delivered by a bridge wire, a laser pulse, an electric spark, a flame, or by other means, the metals undergo self-sustaining exothermic reaction, producing an intermetallic compound. The reaction occurs in solid and liquid phase only, without releasing any gas. One particular type of such materials is aluminum-nickel multilayered foil, that produces (NiAl).
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Hydrous pyrolysis refers to the thermal decomposition which takes place when organic compounds are heated to high temperatures in the presence of water. Many hydrous pyrolysis processes use superheated water in the liquid phase, whereas steam cracking uses water in the gas phase. Steam cracking is used in the petroleum industry to produce the lighter alkenes and in many cases also substantial atmospheric carbon dioxide. Hydrous pyrolysis may be a significant process in the creation of fossil fuels.Pennisi, Elizabeth, Surreptitiously converting dead matter into oil and coal - Water, Water Everywhere, Science News, February 20, 1993.
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The subscripts l, v and i denote liquid phase, vapor phase and vapor-liquid interface, respectively. If the laser intensity is high and pulse duration is short, the so-called Knudsen layer is assumed to exist at the melt-vapor front where the state variables undergo discontinuous changes across the layer. By considering the discontinuity across the Knudsen layer, Yao, et al. (2001) simulated the surface recess velocity Vv distribution, along the radial direction at different times, which indicates the material ablation rate is changing significantly across the Knudsen layer.
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Electrostatic forces between particles are strongest when the charges are high, and the distance between the nuclei of the ions is small. In such cases, the compounds generally have very high melting and boiling points and a low vapour pressure. Trends in melting points can be even better explained when the structure and ionic size ratio is taken into account. Above their melting point ionic solids melt and become molten salts (although some ionic compounds such as aluminium chloride and iron(III) chloride show molecule-like structures in the liquid phase).
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For the heat pipe to transfer heat, it must contain saturated liquid and its vapor (gas phase). The saturated liquid vaporizes and travels to the condenser, where it is cooled and turned back to a saturated liquid. In a standard heat pipe, the condensed liquid is returned to the evaporator using a wick structure exerting a capillary action on the liquid phase of the working fluid. Wick structures used in heat pipes include sintered metal powder, screen, and grooved wicks, which have a series of grooves parallel to the pipe axis.
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His contributions to catalysis and surface chemistry have addressed the challenges associated with combining experiment, calculation and modeling for complex catalysis. For example, he has published numerous papers on the reforming of hydrocarbons, including microkinetic descriptions of hundreds of reactions on supported metals. Other research has addressed liquid phase dehydration and/or hydrodeoxygenation of biomass- derived molecules such as furfural, dimethylfuran, or benzoic acid. He has expanded on general approaches to catalytic design by using descriptors in parallel with efforts to develop reaction models with the accuracy of first principles approaches.
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Parasassi, E.K. Krasnowska, L. Bagatolli, E. Gratton ,Journal of Fluorescence, 1998 which can only be reoriented in the liquid phase. The geometry of the Laurdan molecule is as follows: the Dreiding energy, which is the energy related to the 3D structure of the molecule using the Dreiding force field, is 71.47 kcal/mol. The volume is 377.73 Å3 while the minimal projection area is 53.09 Å2. The minimum z length is 24.09 Å, the maximal projection area is 126.21 Å2 and the maximum z length is 10.33 Å.
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In one of the earlier studies conducted by Manes, M., & Hofer, L. J. E., the Polyani theory was used to characterize liquid-phase adsorption isotherms on various concentrations activated carbon using a wide range of organic solvent. The polyani theory was shown to be a good fit for these various systems. Because of the results, the study introduced the possibility of predicting isotherms for similar systems using minimal data. However, the limitation is that the adsorption isotherms for a large variety of solvents can only fit over a limited range.
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Stiction or adhesion between the substrate (usually silicon based) and the microstructure occurs during the isotropic wet etching of the sacrificial layer. The capillary forces due to the surface tension of the liquid between the microstructure and substrate during drying of the wet etchant cause the two surfaces to adhere together. Separating the two surfaces is often complicated due to the fragile nature of the microstructure. Stiction is often circumvented by the use of a sublimating fluid (often supercritical CO2, which has extremely low surface tension) drying process where the liquid phase is bypassed.
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He went on to obtain a doctorate on "The Dehydrogenation of Alicyclic Compounds and Terpenic Ketones in the Liquid Phase", while lecturing at Sheffield University under Sir Patrick Linstead. He was interned as an 'enemy alien' in England in May 1940 and then Canada, where he formed lasting friendships with Klaus Fuchs, Max Perutz, Hermann Bondi and Tommy Gold. After he returned to Britain in December 1940, he joined the Auxiliary Fire Service whilst working as a chemist in a paint factory. After graduation, he became chief chemist at Milton Antiseptic.
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Fish hydrolysate, in its simplest form, is ground up fish transformed into a liquid phase, where the cleavage of molecular bonds occurs through various biological processes. Raw material choice; either whole fish or by-products, depends on the commercial sources of the fish. In some cases, the fillet portions are removed for human consumption, the remaining fish body (generally the guts, bones, cartilage, scales and remaining meat) is put into water and ground up. Some fish hydrolysate is ground more finely than others so more bone material is able to remain suspended.
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Solid fat index (SFI) is a measure of the percentage of fat in crystalline (solid) phase to total fat (the remainder being in liquid phase) across a temperature gradient. The SFI of a fat is measured using a dilatometer that measures the expansion of a fat as it is heated; density measurements are taken at a series of standardized temperature check points. The resulting SFI/temperature curve is related to melting qualities and flavor. For example, butter has a sharp SFI curve, indicating that it melts quickly and that it releases flavor quickly.
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Hydraulic transport consists of flows in which solid particles are dispersed in a continuous liquid phase. They are often referred to as slurry flows. Applications include the transport of coals and ores to the flow of mud. Suspensions are classified into the following groups; fine suspensions in which the particles are uniformly distributed within the liquid and coarse suspensions where particles ted to travel predominantly in the bottom half of a horizontal pipe at a lower velocity than the liquid and a significantly lower velocity than the liquid in a vertical pipe.
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Cold traps should be assembled such that the down tube is connected to the source of gas whilst the cap is connected to the source of vacuum.An Aldrich manifold including a preformed cold trap Reversing this, connecting the down tube to the source of vacuum, places the inlet of the vacuum directly above the condensate, increasing the chances of vapour phase condensate moving up the (uncooled) down tube (towards the pump) or, should the trap begin to fill to an appreciable volume, liquid phase condensate being pulled into the pump.
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Then draw the equilibrium line using the VLE data points of the lower boiling component, representing the equilibrium vapor phase compositions for each value of liquid phase composition. Also draw vertical lines from the horizontal axis up to the x = y line for the feed and for the desired compositions of the top distillate product and the corresponding bottoms product (shown in red in Figure 1). The next step is to draw the operating line for the rectifying section (the section above the feed inlet) of the distillation column, (shown in green in Figure 1).
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Besides, the contact angles are directly related to whether the solid surface is ideal, in other words, whether it is a smooth, heterogeneous surface. In the Captive Bubble Method, the bubble indicating the liquid drop makes an angle with the solid surface which is called the contact angle. The stability of the liquid phase on the solid is measured with an intrinsic contact angle. Theoretically, the contact angle equals to the value of the local intrinsic contact angle with the assumption of a negligible effect of line tension.
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It is not lattice-matched to HgCdTe, but is much cheaper, as it can be grown by epitaxy on silicon (Si) or germanium (Ge) substrates. Liquid phase epitaxy (LPE), in which a CdZnTe substrate is lowered and spinning on top of the surface of a slowly cooling liquid HgCdTe melt. This gives the best results in terms of crystalline quality, and is still a common technique of choice for industrial production. In recent years, molecular beam epitaxy (MBE) has become widespread because of its ability to stack up layers of different alloy composition.
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An ionic liquid compressor takes advantage of two properties of ionic liquids—their virtually non-measurable vapor pressures and large temperature window for the liquid phase—in combination with the low solubility of some gasses (e.g. hydrogen) in them. This insolubility is exploited by using the body of an ionic liquid to compress hydrogen up to 1000bar (14,500psi)Linde AG: Linde starts small-series production for hydrogen fuelling stations in hydrogen filling stations. Linde's ionic liquid compressor reduced the number of moving parts from about 500 in a conventional reciprocating compressor down to 8.
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Since its first description in 1953, ethylene carbonate has been commonly used as starting material for vinylene carbonate. In the first stage, monochlorethylene carbonate is produced in a UV-initiated photochlorination reaction with chlorine or sulfuryl chloride at 60-70 °C in bulk. In the second stage, monochlorethylenecarbonate undergoes dehydrochlorination with a base such as triethylamine. Vinylencarbonat- Synthese Instead of in the liquid phase, the dehydrochlorination may also be carried out in the gas phase on a zinc chloride impregnated catalyst in a fluidized bed reactor at 350-500 °C.
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AFP-L3 is isolated via an immunoassay and quantified using chemiluminesence on an automated platform. Results for AFP-L3 are represented as a ratio of LCA-reactive AFP to total AFP (AFP-L3%). The AFP-L3% assay, a liquid-phase binding assay, will help to identify at-risk subjects earlier, allowing for more intense evaluation for evidence of HCC according to existing practice guidelines in oncology. AFP-L3% is the standard for quantifying the L3 isoform of AFP in serum of high risk chronic liver disease (CLD) patients.
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The sample support stage is cooled to achieve condensation, for example, to 4 °C for 813 Pa water vapor. The electron optics in high vacuum is separated from the sample chamber by a pump limiting aperture. Detection of backscattered or secondary electrons is optimal when applying a positive electrical potential V between the sample and the detector, so that a cascade of electrons and ions is created. Liquid-phase electron microscopy (LP EM) refers to a class of methods for imaging specimens in liquid with nanometer spatial resolution using electron microscopy.
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This development led to the discovery of fullerenes in 1986 and carbon nanotubes a few years later. In science, a lot is known about properties of the gas phase; however, comparatively little is known about the condensed phases (the liquid phase and solid phase.) The study of clusters attempts to bridge this gap of knowledge by clustering atoms together and studying their characteristics. If enough atoms were clustered together, eventually one would obtain a liquid or solid. The study of atomic and molecular clusters also benefits the developing field of nanotechnology.
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Deposits reduce the heat transfer in the boiler, reduce the flow rate and eventually block boiler tubes. Any non-volatile salts and minerals that will remain when the feedwater is evaporated must be removed, because they will become concentrated in the liquid phase and require excessive "blow- down" (draining) to prevent the formation of solid precipitates. Even worse are minerals that form scale. Therefore, the make-up water added to replace any losses of feedwater must be demineralized/deionized water, unless a purge valve is used to remove dissolved minerals.
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SSM is done at a temperature that puts the metal between its liquidus and solidus temperature. Ideally, the metal should be 30 to 65% solid. The semi-solid mixture must have a low viscosity to be usable, and to reach this low viscosity the material needs a globular primary surrounded by the liquid phase. The temperature range possible depends on the material and for aluminum alloys can be as much as 50 °C, but for narrow melting range copper alloys can be only several tenths of a degree.
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For the solvent, the presence of the solute decreases its vapor pressure by dilution. A nonvolatile solute has a vapor pressure of zero, so the vapor pressure of the solution is less than the vapor pressure of the solvent. Thus, a higher temperature is needed for the vapor pressure to reach the surrounding pressure, and the boiling point is elevated. Put in chemical potential terms, at the boiling point, the liquid phase and the gas (or vapor) phase have the same chemical potential (or vapor pressure) meaning that they are energetically equivalent.
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Residue Curve Principle A residue curve describes the change of the composition of the liquid phase of a chemical mixture during continuous evaporation at the condition of vapor–liquid equilibrium (open distillation). Multiple residue curves for a single system are called residue curves map. Residue curves allow testing the feasibility of a separation of mixtures and therefore are a valuable tool in designing distillation processes. Residue curve maps are typically used for examining ternary mixtures which can't be easily separated by distillation because of azeotropic points or too small relative volatilities.
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A horizontal line (isotherm or tie line) can be drawn through any such system point, and intersects the curve for each phase at its equilibrium composition. The quantity of each phase is given by the lever rule (expressed in the variable corresponding to the x-axis, here mole fraction). For the analysis of fractional distillation, the two independent variables are instead considered to be liquid-phase composition (x1L) and pressure. In that case the phase rule implies that the equilibrium temperature (boiling point) and vapour-phase composition are determined.
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Similar to the previous technique, the TIPS phase separation procedure requires the use of a solvent with a low melting point that is easy to sublime. For example, dioxane could be used to dissolve polylactic acid, then phase separation is induced through the addition of a small quantity of water: a polymer-rich and a polymer-poor phase are formed. Following cooling below the solvent melting point and some days of vacuum-drying to sublime the solvent, a porous scaffold is obtained. Liquid-liquid phase separation presents the same drawbacks of emulsification/freeze-drying.
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Thorium concentrations on the Moon, as mapped by Lunar Prospector. Thorium correlates with the location of KREEP. KREEP, an acronym built from the letters K (the atomic symbol for potassium), REE (rare-earth elements) and P (for phosphorus), is a geochemical component of some lunar impact breccia and basaltic rocks. Its most significant feature is somewhat enhanced concentration of a majority of so-called "incompatible" elements (those that are concentrated in the liquid phase during magma crystallization) and the heat-producing elements, namely radioactive uranium, thorium, and potassium (due to presence of the radioactive 40K).
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18O is two neutrons heavier than 16O and causes the water molecule in which it occurs to be heavier by that amount. The addition of more energy is required to vaporize H218O than H216O, and H218O liberates more energy when it condenses. In addition, H216O tends to diffuse more rapidly. Because H216O requires less energy to vaporize, and is more likely to diffuse to the liquid phase, the first water vapor formed during evaporation of liquid water is enriched in H216O, and the residual liquid is enriched in H218O.
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The key feature of dye-sublimated clothing is that the design is not printed on top of the garment, but permanently dyed into the threads of the shirt, ensuring that it will never fade. Dye-sublimation is economically viable for small-quantity printing; the unit cost is similar for short or long production runs. Screen printing has higher setup costs, requiring large numbers to be produced to be cost- effective, and the unit cost is higher. Solid ink is changed into a gas without passing through a liquid phase (sublimation), using heat and pressure.
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For molecules of a liquid to evaporate, they must be located near the surface, they have to be moving in the proper direction, and have sufficient kinetic energy to overcome liquid-phase intermolecular forces. When only a small proportion of the molecules meet these criteria, the rate of evaporation is low. Since the kinetic energy of a molecule is proportional to its temperature, evaporation proceeds more quickly at higher temperatures. As the faster-moving molecules escape, the remaining molecules have lower average kinetic energy, and the temperature of the liquid decreases.
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PAC probes may also be added during the synthesis of sample materials to achieve the most uniform distribution in the sample. This method is particularly well suited if, for example, the PAC probe diffuses only poorly in the material and a higher concentration in grain boundaries is to be expected. Since only very small samples are necessary with PAC (about 5 mm), micro-reactors can be used. Ideally, the probe is added to the liquid phase of the sol-gel process or one of the later precursor phases.
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Commercial production of cumene is by Friedel–Crafts alkylation of benzene with propylene. Cumene producers account for approximately 20% of the global demand for benzene.Market Study Benzene, published by Ceresana, July 2011 The original route for manufacturing of cumene was by alkylation of benzene in the liquid phase using sulfuric acid as a catalyst, but because of the complicated neutralization and recycling steps required, together with corrosion problems, this process has been largely replaced. As an alternative, solid phosphoric acid (SPA) supported on alumina was used as the catalyst.
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Take for example proteins in water, which would be a liquid phase that is passed through a column. The column is commonly known as the solid phase since it is filled with porous synthetic particles that are of a particular charge. These porous particles are also referred to as beads, may be aminated (containing amino groups) or have metal ions in order to have a charge. The column can be prepared using porous polymers, for macromolecules over 100,000 the optimum size of the porous particle is about 1 μm2.
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By comparison, the liquid temperature range of water (between ice and gas) is just 100K at normal, sea-level atmospheric pressure conditions. Despite sodium's low specific heat (as compared to water), this enables the absorption of significant heat in the liquid phase, even allowing for safety margins. Moreover, the high thermal conductivity of sodium effectively creates a reservoir of heat capacity which provides thermal inertia against overheating. Sodium also need not be pressurized since its boiling point is much higher than the reactor's operating temperature, and sodium does not corrode steel reactor parts.
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Raimondo, N. Crivillers, F. Reinders, F. Sander, M. Mayor, P. Samorì, Enhanced current photo-switching in a field-effect transistor based on photoresponsive gold nanoparticles blended with poly(3-hexylthiophene), Proc. Natl. Acad. Sci. U.S.A. 109, 12375 (2012) He is exploiting supramolecular methods to generate graphene based materials with tunable properties.A. Ciesielski, P. Samorì, Graphene via sonication assisted liquid-phase exfoliation, Chem. Soc. Rev. 43, 381 (2014) His current research is focused on the architecture vs function relationship in supramolecular and graphene-based materials for applications in (opto)electronics and materials science.
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Bacteria have also been detected and identified by FES, either by their odor in air, or by the "SEPTIC" method in liquid phase. In the period of 2006–2009 Signal Processing Inc (Chiman Kwan) developed a portable FES device in collaboration with Texas A&M; University (Laszlo B. Kish) and University of Szeged (Zoltan Gingl and Peter Heszler). Efforts to explore higher-order statistics for FES purposes were led by Janusz Smulko. SPAWAR (United States Navy) related FES projects were led by Gabor Schmera (see the US Navy patent site below).
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Ion-exchange resins in the form of thin membranes are also used in chloralkali process, fuel cells, and vanadium redox batteries. Idealised image of water-softening process, involving replacement of calcium ions in water with sodium ions donated by a cation-exchange resin. Large cation/anion ion exchangers used in water purification of boiler feedwater Ion exchange can also be used to remove hardness from water by exchanging calcium and magnesium ions for sodium ions in an ion-exchange column. Liquid-phase (aqueous) ion-exchange desalination has been demonstrated.
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Since almost all adsorptive separation processes are dynamic -meaning, that they are running under flow - testing porous materials for those applications for their separation performance has to be tested under flow as well. Since separation processes run with mixtures of different components, measuring several breakthrough curves results in thermodynamic mixture equilibria - mixture sorption isotherms, that are hardly accessible with static manometric sorption characterization. This enables the determination of sorption selectivities in gaseous and liquid phase. The determination of breakthrough curves is the foundation of many other processes, like the pressure swing adsorption.
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Because this layer is so thin there is extensive hydrodynamic coupling between the bilayer and the substrate, resulting in a lower diffusion coefficient in supported bilayers than for free bilayers of the same composition. A certain percentage of the supported bilayer will also be completely immobile, although the exact nature of and reason for these “pinned” sites is still uncertain. For high quality liquid phase supported bilayers the immobile fraction is typically around 1-5%. To quantify the diffusion coefficient and mobile fraction, researchers studying supported bilayers will often report FRAP data.
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Matthias Ballauff (born 13 July 1952) is a German chemist and physicist, and is a professor of physics at the Free University of Berlin. His postdoctoral research and training was directed by Paul Flory. He contributed to various areas of physical chemistry, in particular to polymer science, colloidal chemistry and nanomaterials, as well as to soft matter physics. Ballauff is particularly known for having developed new catalyst materials in the form of functionalized metallic nanoparticles dispersed in liquid phase, which can greatly speed up the reaction kinetics of organic molecules.
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Liquid core nuclear engines are fueled by compounds of fissionable elements in liquid phase. A liquid-core engine is proposed to operate at temperatures above the melting point of solid nuclear fuel and cladding, with the maximum operating temperature of the engine instead being determined by the reactor pressure vessel and neutron reflector material. The higher operating temperatures would be expected to deliver specific impulse performance on the order of 1300 to 1500 seconds (12.8-14.8 kN·s/kg). A liquid-core reactor would be extremely difficult to build with current technology.
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Carbonic anhydrase could in principle prove relevant to carbon capture. Some carbonic anhydrases can withstand temperatures up to 107 °C and extreme alkalinity (pH > 10). A pilot run with the more stable CA on a flue stream that consisted of 12–13% mol composition CO₂ had a capture rate of 63.6% over a 60-hour period with no noticeable effects in enzyme performance. CA was placed in a N-methyldiethanolamine (MDEA) solution where it served to increase the concentration difference (driving force) of CO2 between the flue stream of the power plant and liquid phase in a liquid-gas contactor.
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Using nuclear magnetic resonance spectroscopy (NMR), Khetrapal studied the molecules orientation in the nematic phase of liquid crystals, the non-planar distortions in peptides in the liquid phase and weak molecular interactions involved in hydrogen bonding. Apart from pioneering NMR studies in India, he established Institute of Interdisciplinary Studies and Institute of Professional Studies at Allahabad University. His contributions are also reported behind the establishment of the National Centre on NMR in Bangalore. He has published a number of articles and books, besides contributing chapters to books published by others including the 8-volume Encyclopedia of Nuclear Magnetic Resonance.
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Many wing muscles are large and may be as large as 10 mm in length and 2 mm in width. Moreover, in some Diptera the fibres are of giant dimensions. For instance, in the very active Rutilia, the cross-section is 1800 µm long and more than 500 µm wide. The transport of fuel and oxygen from the surroundings to the sites of consumption and the reverse transport of carbon dioxide therefore represent a challenge to the biologist both in relation to transport in the liquid phase and in the intricate system of air tubes, i.e.
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The rare- earth elements patterns observed in igneous rocks are primarily a function of the chemistry of the source where the rock came from, as well as the fractionation history the rock has undergone. Fractionation is in turn a function of the partition coefficients of each element. Partition coefficients are responsible for the fractionation of a trace elements (including rare- earth elements) into the liquid phase (the melt/magma) into the solid phase (the mineral). If an element preferentially remains in the solid phase it is termed ‘compatible’, and it preferentially partitions into the melt phase it is described as ‘incompatible’.
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A plate column (or tray column) is a chemical equipment used to carry out unit operations where it is necessary to transfer mass between a liquid phase and a gas phase. In other words, it is a particular gas-liquid contactor. The peculiarity of this gas-liquid contactor is that the gas comes in contact with liquid through different stages; each stage is delimited by two plates (except the stage at the top of the column and the stage at the bottom of the column). Some common applications of plate columns are distillation, gas-liquid absorption and liquid-liquid extraction.
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Washing plates in water, dilute ammonia, triethanolamine or (more recently) silver nitrate solutions was found to be very effective, especially for red- and infrared-sensitive materials. Later types of fine grain, near-IR-sensitive plates were unusable without such hypersensitizing. However, much skill and persistence was required to obtain consistent and uniform results, especially with large plates, which were often treated at unsocial hours in observatory darkrooms on remote mountain tops. The liquid-phase plate washing techniques operate by removing residual soluble bromides or iodides from the emulsion, thereby increasing the silver ion concentration in the vicinity of the photosensitive grain.
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The droplets agglomerate to larger drops, and the swirl of the gas causes cyclonic separation.Malyshkina, M. M., The Structure of Gasdynamic Flow in a Supersonic Separator of Natural Gas, High Temperature (2008, Vol 46, No 1, ISSN 0018-151X). The dry gas continues forward, while the liquid phase together with some slip gas (about 30% of the total stream) is separated by a concentric divider and exits the device as a separate stream. The final section are diffusers for both streams, where the gas is slowed down and about 80% of the feed pressure (depending on application) is recovered.
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Distillation is a process used to separate or partially separate components in a mixture by boiling (vaporization) followed by condensation. Distillation takes advantage of differences in concentrations of components in the liquid and vapor phases. In mixtures containing two or more components, the concentrations of each component are often expressed as mole fractions. The mole fraction of a given component of a mixture in a particular phase (either the vapor or the liquid phase) is the number of moles of that component in that phase divided by the total number of moles of all components in that phase.
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Another area of medicinal research in which the Janda laboratory has made contributions encompasses techniques to create molecular diversity, uncover active components from complex mixtures and the separation of synthetic targets by phase tagging. He has published methodologies that allow implementation of what has been termed "encoded combinatorial libraries", providing a means whereby the alternating parallel synthesis of peptides and oligonucleotides can be performed in a routine manner. His group has also demonstrated a technology termed "recursive deconvolution of combinatorial libraries" and "liquid phase combinatorial synthesis" which showed that reactants, products and by-products can be effectively "tagged" and targeted to different phases,.
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Ikeda, H. Nur, T. Sawadaishi, K. Ijiro, M. Shimomura, B. Ohtani, Direct observation of bimodal amphiphilic surface structures of zeolite particles for a novel liquid-liquid phase boundary catalysis, Langmuir, 2001, (17) 7976 – 7979. AbstractH. Nur, S. Ikeda and B. Ohtani, Phase-boundary catalysts for acid- catalyzed reactions: the role of bimodal amphiphilic structure and location of active sites, Journal of Brazilian Chemical Society, 2004, (15) 719–724 – 2236. PaperH. Nur, S. Ikeda, and B. Ohtani, Amphiphilic NaY zeolite particles loaded with niobic acid: Materials with applications for catalysis in immiscible liquid-liquid system, Reaction Kinetics and Catalysis Letters, 2004, (17) 255 – 261.
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COSMOSPACE (COSMO Surface-Pair Activity Coefficient Equation) is an activity coefficient model in which the activity coefficient of the components in a liquid chemical mixture can be related through their molar fraction.Andreas Klamt, Gerard J. P. Krooshof, Ross Taylor "COSMOSPACE: Alternative to conventional activity-coefficient models", AIChE J., 48(10), 2332–2349, (2002) It was initially developed as an implicit solution to COSMO-RS. While UNIQUAC is a first order approximation, COSMOSPACE gives the exact solution of a lattice model in which pairwise molecule surfaces interact. Therefore, COSMOSPACE outperforms Uniquac in the description of vapor–liquid and liquid–liquid phase equilibria.
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The activity coefficient of the components in a system is a correction factor that accounts for deviations of real systems from that of an Ideal solution, which can either be measured via experiment or estimated from chemical models (such as UNIFAC). By adding a correction factor, known as the activity (a_i, the activity of the ith component) to the liquid phase fraction of a liquid mixture, some of the effects of the real solution can be accounted for. The activity of a real chemical is a function of the thermodynamic state of the system, i.e. temperature and pressure.
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Recent discoveries include the aggregation of proteins that form liquid-like droplets within the cytosol, an example of biological phase separation (liquid-liquid phase separation). The second area Gladfelter's lab explores is how cells sense their shape. Because septins localize to areas of the cell that change shape or are highly curved, they are the proteins Gladfelter and her team examine. Septins are involved in many processes that occur in eukaryotic cells, including cytokinesis, formation of diffusion barriers to compartmentalize the plasma membrane, and regulation of cellular processes such as the release of neurotransmitters and microtubule dynamics.
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Because water has good properties as a coolant, water plus antifreeze is used in internal combustion engines and other heat transfer applications, such as HVAC chillers and solar water heaters. The purpose of antifreeze is to prevent a rigid enclosure from bursting due to expansion when water freezes. Commercially, both the additive (pure concentrate) and the mixture (diluted solution) are called antifreeze, depending on the context. Careful selection of an antifreeze can enable a wide temperature range in which the mixture remains in the liquid phase, which is critical to efficient heat transfer and the proper functioning of heat exchangers.
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Solid rockets use propellant in the solid phase, liquid fuel rockets use propellant in the liquid phase, gas fuel rockets use propellant in the gas phase, and hybrid rockets use a combination of solid and liquid or gaseous propellants. In the case of solid rocket motors, the fuel and oxidizer are combined when the motor is cast. Propellant combustion occurs inside the motor casing, which must contain the pressures developed. Solid rockets typically have higher thrust, less specific impulse, shorter burn times, and a higher mass than liquid rockets, and additionally cannot be stopped once lit.
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The addition of a material separation agent, such as benzene to an ethanol/water mixture, changes the molecular interactions and eliminates the azeotrope. Added in the liquid phase, the new component can alter the activity coefficient of various compounds in different ways thus altering a mixture's relative volatility. Greater deviations from Raoult's law make it easier to achieve significant changes in relative volatility with the addition of another component. In azeotropic distillation the volatility of the added component is the same as the mixture, and a new azeotrope is formed with one or more of the components based on differences in polarity.
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Born on 4 March 1929 in Amsterdam,Johanna Maria Henrica Levelt The Chris Sengers Pages Netherlands,(Anneke) Levelt Sengers - Institute for Physical Science and ... Levelt Sengers earned candidaatsJohanna M. Levelt-Sengers The National Institute of Standards and Technology (an undergraduate degree) in physics and chemistry from the University of Amsterdam in 1950, and completed her Ph.D. from the same university in 1958. Her dissertation, Measurements of the Compressibility of Argon in the Gaseous and Liquid Phase, was jointly promoted by and . She emigrated to the United States in 1963 and joined the National Bureau of Standards (later renamed to NIST).
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Recently, the biophysics of RNA granule formation has been shown to fall under the aegis of a general property, termed liquid liquid phase separation (LLPS). LLPS occurs when RNA binding proteins associate to form structures analogous to liquid droplets, which separate from surrounding aqueous medium. The Wolozin laboratory has extended this work to explain the pathophysiology of Alzheimer's disease Work from the Wolozin laboratory demonstrates that the pathology occurring in neurons (neurofibrillary tangles) is associated with RNA binding proteins. This appears to occur because tau (the main building block of neurofibrillary tangles) stimulates stress granule formation.
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The boiling point elevation happens both when the solute is an electrolyte, such as various salts, and a nonelectrolyte. In thermodynamic terms, the origin of the boiling point elevation is entropic and can be explained in terms of the vapor pressure or chemical potential of the solvent. In both cases, the explanation depends on the fact that many solutes are only present in the liquid phase and do not enter into the gas phase (except at extremely high temperatures). Put in vapor pressure terms, a liquid boils at the temperature when its vapor pressure equals the surrounding pressure.
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The chemical potential is dependent on the temperature, and at other temperatures either the liquid or the gas phase has a lower chemical potential and is more energetically favorable than the other phase. This means that when a nonvolatile solute is added, the chemical potential of the solvent in the liquid phase is decreased by dilution, but the chemical potential of the solvent in the gas phase is not affected. This means in turn that the equilibrium between the liquid and gas phase is established at another temperature for a solution than a pure liquid, i.e., the boiling point is elevated.
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One order parameter represents a solid nanoparticle, while the other represents the liquid phase. Each of the order parameters is a function of particle radius. The parabolic Landau potentials for the liquid and solid phases are calculated at a given temperature, with the lesser Landau a potential assumed to be the equilibrium state at any point in the particle. In the temperature range of surface melting, the results show that the Landau curve of the ordered state is favored near the center of the particle while the Landau curve of the disordered state is smaller near the surface of the particle.
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In other cases, severe deviations from Raoult's law and Dalton's law are observed, most famously in the mixture of ethanol and water. These compounds, when heated together, form an azeotrope, which is when the vapor phase and liquid phase contain the same composition. Although there are computational methods that can be used to estimate the behavior of a mixture of arbitrary components, the only way to obtain accurate vapor–liquid equilibrium data is by measurement. It is not possible to completely purify a mixture of components by distillation, as this would require each component in the mixture to have a zero partial pressure.
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The contacted surface layer containing the eutectic composites melts, forming a liquid phase alloy, accelerating further mixing processes and diffusion until the saturation composition is reached. Other common eutectic bonding alloys commonly used for wafer bonding include Au-Sn, Al-Ge, Au-Ge, Au-In and Cu-Sn. The chosen bonding temperature usually is some degrees higher than the eutectic temperature so the melt becomes less viscous and readily flows due to higher roughness to surface areas that are not in atomic contact. To prevent the melt pressed outside the bonding interface the optimization of the bonding parameter control is necessary, e.g.
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By applying reagents in the gas phase instead of the liquid phase, the retention of the sample during the analysis and the sensitivity of the instrument were increased. Polybrene was used as a substrate coating to better anchor proteins and peptides, and the purification of reagents was improved. HPLC analysis techniques were used to reduce analysis times and extend the technique's applicable range. The amount of protein required for an analysis decreased, from 10-100 nanomoles for Edman and Begg's protein sequencer, to the low picomole range, a revolutionary increase in the sensitivity of the technology.
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Addition of solute to form a solution stabilizes the solvent in the liquid phase, and lowers the solvent chemical potential so that solvent molecules have less tendency to move to the gas or solid phases. As a result, liquid solutions slightly above the solvent boiling point at a given pressure become stable, which means that the boiling point increases. Similarly, liquid solutions slightly below the solvent freezing point become stable meaning that the freezing point decreases. Both the boiling point elevation and the freezing point depression are proportional to the lowering of vapour pressure in a dilute solution.
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The four bonds are of the same length and strength, which yields a molecular structure as shown below: A schematic presentation of hybrid orbitals overlapping hydrogens' s orbitals Owing to these exceptional theories, Pauling won the 1954 Nobel Prize in Chemistry. Notably he has been the only person to ever win two unshared Nobel prizes, winning the Nobel Peace Prize in 1963. In 1926, French physicist Jean Perrin received the Nobel Prize in physics for proving, conclusively, the existence of molecules. He did this by calculating Avogadro's number using three different methods, all involving liquid phase systems.
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Thus, the ordinary concrete transforms to nanoconcrete. The initial natural process of cement hydration with formation of colloidal globules about 5 nm in diameter spreads into the entire volume of cement–water matrix as the energy expended upon the mix. The liquid activated high-energy mixture can be used by itself for casting small architectural details and decorative items, or foamed (expanded) for lightweight concrete. HEM Nanoconcrete hardens in low and subzero temperature conditions because the liquid phase inside the nano-pores of C-S-H gel doesn't freeze at temperatures from −8 to −42 degrees Celsius.
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GAC can be either in granular or extruded form. GAC is designated by sizes such as 8×20, 20×40, or 8×30 for liquid phase applications and 4×6, 4×8 or 4×10 for vapor phase applications. A 20×40 carbon is made of particles that will pass through a U.S. Standard Mesh Size No. 20 sieve (0.84 mm) (generally specified as 85% passing) but be retained on a U.S. Standard Mesh Size No. 40 sieve (0.42 mm) (generally specified as 95% retained). AWWA (1992) B604 uses the 50-mesh sieve (0.297 mm) as the minimum GAC size.
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Dye-based inks are generally much stronger than pigment-based inks and can produce much more color of a given density per unit of mass. However, because dyes are dissolved in the liquid phase, they have a tendency to soak into paper, potentially allowing the ink to bleed at the edges of an image. To circumvent this problem, dye-based inks are made with solvents that dry rapidly or are used with quick-drying methods of printing, such as blowing hot air on the fresh print. Other methods include harder paper sizing and more specialized paper coatings.
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The reactions by the direct oxidation method consist of two-step oxidation of isobutylene or TBA with air to produce methacrylic acid and esterification by methanol to produce MMA. :CH2=C(CH3)2 (or (CH3)3C–OH) + O2 → CH2=C(CH3)–CHO + H2O :CH2=C(CH3)CHO + O2 → CH2=C(CH3)CO2H :CH2=C(CH3)CO2H + CH3OH → CH2=C(CH3)CO2CH3 \+ H2O A process using isobutylene as a raw material has been commercialized by Escambia Co. Isobutylene is oxidized to provide α-hydroxy isobutyric acid. The conversion uses N2O4 and nitric acid at 5–10 °C in the liquid phase. After esterification and dehydration MMA is obtained.
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Factors which influence this include the atmospheric abundance of the two gases, the supply of the gases to the site of fixation (i.e. in land plants: whether the stomata are open or closed), the length of the liquid phase (how far these gases have to diffuse through water in order to reach the reaction site). For example, when the stomata are closed to prevent water loss during drought: this limits the supply, while production within the leaf will continue. In algae (and plants which photosynthesise underwater); gases have to diffuse significant distances through water, which results in a decrease in the availability of relative to .
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Although some reactions involving catalytic hydrogenation of organic substances were already known, the property of finely divided nickel to catalyze the fixation of hydrogen on hydrocarbon (ethylene, benzene) double bonds was discovered by the French chemist Paul Sabatier in 1897.C.R.Acad.Sci. 1897, 132, 210C.R.Acad.Sci. 1901, 132, 210 Through this work, he found that unsaturated hydrocarbons in the vapor phase could be converted into saturated hydrocarbons by using hydrogen and a catalytic metal, laying the foundation of the modern catalytic hydrogenation process. Soon after Sabatier's work, a German chemist, Wilhelm Normann, found that catalytic hydrogenation could be used to convert unsaturated fatty acids or glycerides in the liquid phase into saturated ones.
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Depending on context, that process also may be called atmospheric icing. The ice it produces differs in some ways from crystalline frost, which consists of spicules of ice that typically project from the solid surface on which they grow. The main difference between the ice coatings and frost spicules arises from the fact that the crystalline spicules grow directly from desublimation of water vapour from air, and desublimation is not a factor in icing of freezing surfaces. For desublimation to proceed the surface must be below the frost point of the air, meaning that it is sufficiently cold for ice to form without passing through the liquid phase.
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The supersonic separator requires a certain process scheme, which includes further auxiliary equipment and often forms a skid or processing block. The typical basic scheme for supersonic separation is an arrangement where the feed gas is pre-cooled in a heat exchanger by the dry stream of the separator unit. The liquid phase from the supersonic separator goes into a 2-phase or 3-phase separator, where the slip gas is separated from water and/or from liquid hydrocarbons. The gaseous phase of this secondary separator joins the dry gas of the supersonic separator, the liquids go for transport, storage or further processing and the water for treatment and disposal.
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The various liquid-crystal phases (called mesophases) can be characterized by the type of ordering. One can distinguish positional order (whether molecules are arranged in any sort of ordered lattice) and orientational order (whether molecules are mostly pointing in the same direction), and moreover order can be either short-range (only between molecules close to each other) or long- range (extending to larger, sometimes macroscopic, dimensions). Most thermotropic LCs will have an isotropic phase at high temperature. That is that heating will eventually drive them into a conventional liquid phase characterized by random and isotropic molecular ordering (little to no long- range order), and fluid-like flow behavior.
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Also transferred to the station were Mir Glovebox Stowage (MGBX) equipment to replenish glovebox already on station; Queen's University Experiment in Liquid Diffusion (QUELD) flown in orbiter middeck locker; and the High Temperature Liquid Phase Sintering (LPS) experiment. On flight day six, Godwin and Clifford conducted what some claim to be the first U.S. extravehicular activity (EVA) around two mated spacecraft. However, this appears to ignore the Apollo 9 EVA, and EVAs during Skylab. During six-hour, two-minute, 28-second EVA, they attached four Mir Environmental Effects Payload (MEEP) experiments to the station's docking module - designed to characterize the environment around Mir over an 18-month period.
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Dye-sub printing is a digital printing technology using full color artwork that works with polyester and polymer-coated substrates. Also referred to as digital sublimation, the process is commonly used for decorating apparel, signs and banners, as well as novelty items such as cell phone covers, plaques, coffee mugs, and other items with sublimation-friendly surfaces. The process uses the science of sublimation, in which heat and pressure are applied to a solid, turning it into a gas through an endothermic reaction without passing through the liquid phase. In sublimation printing, unique sublimation dyes are transferred to sheets of “transfer” paper via liquid gel ink through a piezoelectric print head.
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The ArDM (Argon Dark Matter) Experiment is a particle physics experiment based on a liquid argon detector, aiming at measuring signals from WIMPs (Weakly Interacting Massive Particles), which probably constitute the Dark Matter in the universe. Elastic scattering of WIMPs from argon nuclei is measurable by observing free electrons from ionization and photons from scintillation, which are produced by the recoiling nucleus interacting with neighbouring atoms. The ionization and scintillation signals can be measured with dedicated readout techniques, which constitute a fundamental part of the detector. In order to get a high enough target mass the noble gas argon is used in the liquid phase as target material.
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The 730 m (2,400 ft) icefall (center) in the Roosevelt Glacier, Mount Baker, Washington, U.S. An icefall is a portion of certain glaciers characterized by relatively rapid flow and chaotic crevassed surface, caused in part by gravity. The term icefall is formed by analogy with the word waterfall, which is a similar phenomenon of the liquid phase but at a more spectacular speed. When ice movement of a glacier is faster than elsewhere, because the glacier bed steepens or narrows, and the flow cannot be accommodated by plastic deformation, the ice fractures, forming crevasses. Where two fractures meet, seracs (or ice towers) can be formed.
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Ion exchange technology has advantages of being well-suitable for perchlorate treatment and high volume throughput but has a downside that it does not treat chlorinated solvents. In addition, ex situ technology of liquid phase carbon adsorption is employed, where granular activated carbon (GAC) is used to eliminate low levels of perchlorate and pretreatment may be required in arranging GAC for perchlorate elimination. In situ treatments, such as bioremediation via perchlorate-selective microbes and permeable reactive barrier, are also being used to treat perchlorate. In situ bioremediation has advantages of minimal above-ground infrastructure and its ability to treat chlorinated solvents, perchlorate, nitrate, and RDX simultaneously.
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The advantage of a gas phase reaction over a comparable liquid phase process is the control of moisture from the ambient environment, which often results in cross polymerization of the silane leading to particulates on the treated surface. Often a heated sub- atmospheric vacuum chamber is used to allow precise control of the reactants and water content. Additionally the gas phase process allows for easy treatment of complex parts since the coverage of the reactant is generally diffusion limited. Microelectromechanical Systems (MEMS) sensors often use molecular vapor deposition as a technique to address stiction and other parasitic issues relative to surface-to-surface interactions.
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He is an Associate Editor of the Journal of the American Chemical Society His research interests are in the field of preparative macro- and supramolecular chemistry. Among other things, his group has succeeded in synthesizing and characterizing hitherto unattainable large polycyclic aromatics such as superphenalene, which has a molecular mass of 1182 g·mol−1 and consists of 34 condensed benzene rings.From Hexa‐peri‐hexabenzocoronene to “Superacenes” Structure of superphenalene He has developed small disc-like organic building blocks using alkyl-substituted hexabenzocoronene, and in particular HBC-C12Hexakis(n-dodecyl)-peri-hexabenzocoronene, dodecyl-substituted hexabenzocoronene. \- which self-assembles into crystalline liquid-phase structures (columnar liquid crystals) as potential organic field-effect transistors.
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Even though complexes containing dihydridoiron was known since 1931, the simple compound with the molecular formula is only a much more recent discovery. Following the discovery of the first complex containing dihydridoiron, tetracarbonylate, it was also quickly discovered that it is not possible to remove the carbon monoxide by thermal means - heating an dihydridoiron containing complex only causes it to decompose, a habit attributable to the weak iron-hydrogen bond. Thus, a practical method has been sought since then for the production of the pure compound, without the involvement of a liquid phase. Furthermore, there is also on going research into its other adducts.
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The interfacing mechanism is contained inside a common EI source, like that found in any GC-MS system. The liquid phase from a nano HPLC column is admitted from the capillary column port, where the connection tubing and the nebulizer are first introduced and sealed to prevent vacuum loss. The mechanism is based on the formation of an aerosol in high-vacuum conditions, followed by a quick droplet desolvation and final vaporization of the solute prior to the ionization. The completion of the process is quick and complete and reduces chances of thermal decomposition as reported in the Figure, where a scheme of the interface is shown.
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The core of the interface is represented by the micro-nebulizer. The nebulizer tip protrudes into the ion source so that the spray expansion is completely contained inside the ion volume. The eluate emerges as liquid phase at a flow rate of 300-500 nL/min, and any premature in-tube solvent evaporation is prevented by a convenient thermal insulation of the nebulizer and the connecting tubing from the surrounding source heat. The high temperature of the ion source, between 300 and 400°C, has a double function: to compensate for the latent heat of vaporization during the droplet desolvation, and to convert the solute into the gas phase.
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A chemical in its solid state may receive a different UN number than the liquid phase if their hazardous properties differ significantly; substances with different levels of purity (or concentration in solution) may also receive different UN numbers. UN numbers range from UN 0004 to about UN 3548 (UN 0001 – UN 0003 are no longer in use) and are assigned by the United Nations Committee of Experts on the Transport of Dangerous Goods. They are published as part of their Recommendations on the Transport of Dangerous Goods, also known as the Orange Book. These recommendations are adopted by the regulatory organization responsible for the different modes of transport.
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Oil heaters consist of metal columns with cavities inside which a heat transfer oil flows freely around the heater. A heating element at the base of the heater heats up the oil, which then flows around the cavities of the heater by convection. The oil has a relatively high specific heat capacity and high boiling point. The high specific heat capacity allows the oil to effectively transfer thermal energy from the heating element, while the oil's high boiling point allows it to remain in the liquid phase for the purpose of heating, so that the heater does not have to be a high pressure vessel.
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A small Stretford reactor for scrubbing H2S from geothermal steam The Stretford process was developed during the late 1950s to remove hydrogen sulfide (H2S) from town gas. It was the first liquid phase, oxidation process for converting H2S into sulfur to gain widespread commercial acceptance. Developed by Tom Nicklin of the North Western Gas Board (NWGB) and the Clayton Aniline Company, in Manchester, England, the name of the process was derived from the location of the NWGB's laboratories, in Stretford. The process uses reduction-oxidation (redox) chemistry to oxidise the H2S into elemental sulfur, in an alkaline solution containing vanadium as an oxygen carrier.
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One of the main drawbacks of the technique is the reduced efficiency that is caused by the micelles. Despite the sometimes poor efficiency, MLC is a better choice than ion-exchange LC or ion-pairing LC for separation of charged molecules and mixtures of charged and neutral species. Some of the aspects which will be discussed are the theoretical aspects of MLC, the use of models in predicting retentive characteristics of MLC, the effect of micelles on efficiency and selectivity, and general applications of MLC. Reverse phase high-performance liquid chromatography (RP-HPLC) involves a non-polar stationary phase, often a hydrocarbon chain, and a polar mobile or liquid phase.
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If the decrepitation begins at a temperature less than the temperature required to form the mineral, it is likely that the rate of decrepitation will speed up once the temperature exceeds that of the initial heating . For metamorphic rocks, there are certain principles for measuring the decrepitations. What is known as D1 decrepitation, is classified as a temperature range of about 200-300℃, and is caused by the liquid phase which occupies intricate inclusions, as in hydrothermal minerals. D2 decrepitation is characterized by a starting heat range of about 300-700℃, the temperature can also increase rapidly for a few hundred degrees, such as in solid inclusions.
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Four thermodynamic variables which may describe the system include temperature (T), pressure (p), mole fraction of component 1 (toluene) in the liquid phase (x1L), and mole fraction of component 1 in the vapour phase (x1V). However, since two phases are present () in equilibrium, only two of these variables can be independent (). This is because the four variables are constrained by two relations: the equality of the chemical potentials of liquid toluene and toluene vapour, and the corresponding equality for benzene. For given T and p, there will be two phases at equilibrium when the overall composition of the system (system point) lies in between the two curves.
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Dichlorosilane was originally prepared in 1919 by the gas- phase reaction of monosilane, SiH4, with hydrogen chloride, HCl, and then reported by Stock and Somieski.Seyferth, D., Prud’Homme, C., Wiseman, G., Cyclic Polysiloxanes from the Hydrolysis of Dichlorosilane, Inorganic Chemistry, 22, 2163-2167 It was found that in the gas phase, dichlorosilane will react with water vapor to give a gaseous monomeric prosiloxane, H2SiO. Prosiloxane polymerizes rapidly in the liquid phase and slowly in the gas phase, which results in liquid and solid polysiloxanes [H2SiO]n. The liquid portion of the product, which is collected via vacuum distillation, becomes viscous and gelled at room temperature.
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There may be situations in which only the flow rate of the single key gas component is required, in this case single phase metering may be employed. The measurement can then be adjusted to compensate for the effect of the liquid on the meter. Some of the techniques available for measuring the liquid phase include: A Test separator which determines the phase flow rates by physical separation of the liquid from the gas, with each phase then metered separately. This method provides information on all phases which can then be used to calculate the correction required for a meter and to check the gas flow through the meter.
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The liquid phase ligand binding assay of Immunoprecipitation (IP) is a method that is used to purify or enrich a specific protein, or a group of proteins, using an antibody from a complex mixture. The extract of disrupted tissue or cells is mixed with an antibody against the antigen of interest, which produces the antigen- antibody complex. When antigen concentration is low, the antigen-antibody complex precipitation can take hours or even days and becomes hard to isolate the small amount of precipitate formed. The enzyme-linked immunosorbent assay (ELISA) or Western blotting are two different ways that the purified antigen (or multiple antigens) can be obtained and analyzed.
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Above 0 °C, an H2O molecule that is in the liquid phase (liquid water) has a lower chemical potential than a water molecule that is in the solid phase (ice). When some of the ice melts, H2O molecules convert from solid to liquid where their chemical potential is lower, so the ice cubes shrink. Below 0 °C, the molecules in the ice phase have the lower chemical potential, so the ice cubes grow. At the temperature of the melting point, 0 °C, the chemical potentials in water and ice are the same; the ice cubes neither grow nor shrink, and the system is in equilibrium.
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Anyone employing an incubator shaker (thermal shaker) to grow yeast or bacteria in the laboratory needs to beware that under the usual conditions encountered in the lab, the rate at which oxygen diffuses from the gaseous phase into the shaken liquid phase is too slow to keep up with the rate at which the oxygen is consumed by for example E coli dividing every half hour or S cerevisiae dividing every hour. If the investigator measure the oxygen in the shake flask on the shaker -- polarographically, for example -- at mid-exponential phase of growth, the dissolved oxygen concentration will turn out to be zero.
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However, publication of the announcement of the first room temperature continuously operating double heterostructure laser was by Zhores Alferov in 1970 one month before Hayashi and Panish published similar results. Although there was some degree of contact between the group in Leningrad and the group in New Jersey including a visit by Alferov to the New Jersey lab, the two achievements were obtained independently. Panish experimented with making wafers using a new form of liquid-phase epitaxy while Hayashi tested the laser properties. Panish and Hayashi observed what they thought might be CW operation in several wafers in the weeks before their final demonstration.
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Sketch of the working principle of a xenon dual-phase TPC The XENON experiment operates a dual phase time projection chamber (TPC), which utilizes a liquid xenon target with a gaseous phase on top. Two arrays of photomultiplier tubes (PMTs), one at the top of the detector in the gaseous phase (GXe), and one at the bottom of the liquid layer (LXe), detect scintillation and electroluminescence light produced when charged particles interact in the detector. Electric fields are applied across both the liquid and gaseous phase of the detector. The electric field in the gaseous phase has to be sufficiently large to extract electrons from the liquid phase.
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Van der Waals noted the non-ideality of gases and attributed it to the existence of molecular or atomic interactions. His new formula revolutionized the study of equations of state, and was most famously continued via the Redlich-Kwong equation of state (1949) and the Soave modification of Redlich-Kwong. While the Van der Waals equation is definitely superior to the ideal gas law and does predict the formation of a liquid phase, the agreement with experimental data is limited for conditions where the liquid forms. Except at higher pressures, the real gases do not obey Van der Waals equation in all ranges of pressures and temperatures.
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If this is done via the intake system, the mixture is, in effect, enriched, creating a mixture control and pollution issue. If it is done by venting to the outside, the result is direct hydrocarbon pollution and an effective loss of fuel efficiency and possibly a fuel odor problem. For this reason, some fuel delivery systems allow fuel vapor to be returned to the fuel tank to be condensed back to the liquid phase, or using an active carbon filled canister where fuel vapor is absorbed. This is usually implemented by removing fuel vapor from the fuel line near the engine rather than from the float bowl.
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Owing to the Gibbs–Thomson effect of the confinement of liquids in pores, water in soil can remain liquid at a temperature that is below the bulk freezing point of water. Very fine pores have a very high curvature, and this results in the liquid phase being thermodynamically stable in such media at temperatures sometimes several tens of degrees below the bulk freezing point of the liquid.John Tyndall (1858) "On some physical properties of ice," Philosophical Transactions of the Royal Society of London, 148 : 211–229. Summarized in: This effect allows water to percolate through the soil towards the ice lens, allowing the lens to grow.
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To increase the figure of merit (zT), a material’s thermal conductivity should be minimized while its electrical conductivity and Seebeck coefficient is maximized. In most cases, methods to increase or decrease one property result in the same effect on other properties due to their interdependence. A novel processing technique exploits the scattering of different phonon frequencies to selectively reduce lattice thermal conductivity without the typical negative effects on electrical conductivity from the simultaneous increased scattering of electrons. In a bismuth antimony tellurium ternary system, liquid-phase sintering is used to produce low-energy semicoherent grain boundaries, which do not have a significant scattering effect on electrons.
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This result is obtained from an approximate solution to the governing Smoluchowski convection-diffusion equation obtained via the method of matched asymptotic expansions. The theory explains a characteristic lag- time in the shear-induced aggregation of the particles, which decreases exponentially with the shear rate. It also explains the subsequent runaway (autocatalytic) regime of aggregation kinetics after the lag-time, as well as the characteristic bimodal cluster size distribution of aggregates found typically in shear-induced aggregating and self-assembling systems. Furthermore, the theory has been verified across widely different flow conditions, in terms of different particles and microfluidic systems, and viscoelastic properties of the liquid phase.
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This means that generally the larger hailstones will form some distance from the stronger updraft where they can pass more time growing As the hailstone grows it releases latent heat, which keeps its exterior in a liquid phase. Undergoing 'wet growth', the outer layer is sticky, or more adhesive, so a single hailstone may grow by collision with other smaller hailstones, forming a larger entity with an irregular shape. The hailstone will keep rising in the thunderstorm until its mass can no longer be supported by the updraft. This may take at least 30 minutes based on the force of the updrafts in the hail-producing thunderstorm, whose top is usually greater than high.
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The target facility, which holds the inventory of about 10 m3 of Li, forms and conditions the beam target. The Li screen fulfills two main functions: to react with the deuterons to generate a stable neutron flux in the forward direction and to dissipate the beam power in a continuous manner. The flowing Li (15 m/s; 250 °C) is shaped and accelerated in the proximity of the beam interaction region by a two-stage reducer nozzle forming a concave jet of 25 mm thickness with a minimum radius of curvature of 250 mm in the beam footprint area. The resulting centrifugal pressure raises the boiling point of the flowing Li and thus ensures a stable liquid phase.
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It is important to understand that these advantages are more applicable to the decision between using a batch, a semibatch or a continuous reactor in a certain process. Both batch and semibatch reactors are more suitable for liquid phase reactions and small scale production, because they usually require lower capital costs than a continuously stirred tank reactor operation (CSTR), but incur greater costs per unit if production needs to be scaled up. These per unit costs include labor, materials handling (filling, emptying, cleaning), protective measures, and nonproductive periods that result from changeovers when switching batches. Hence, the capital costs must be weighed against operating costs to determine the correct reactor design to be implemented.
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These smaller organic molecules begin to dissolve and move to the liquid phase, followed by hydrolysis of these organic molecules, and the hydrolyzed compounds then undergo transformation and volatilization as carbon dioxide (CO2) and methane (CH4), with rest of the waste remaining in solid and liquid phases. During the early phases, little material volume reaches the leachate, as the biodegradable organic matter of the waste undergoes a rapid decrease in volume. Meanwhile, the leachate's chemical oxygen demand increases with increasing concentrations of the more recalcitrant compounds compared to the more reactive compounds in the leachate. Successful conversion and stabilization of the waste depends on how well microbial populations function in syntrophy, i.e.
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Clinker nodules produced by sintering at 1450 °C. By far the most common type of cement is hydraulic cement, which hardens by hydration of the clinker minerals when water is added. Hydraulic cements (such as Portland cement) are made of a mixture of silicates and oxides, the four main mineral phases of the clinker, abbreviated in the cement chemist notation, being: :C3S: Alite (3CaO·SiO2); :C2S: Belite (2CaO·SiO2); :C3A: Tricalcium aluminate (3CaO·Al2O3) (historically, and still occasionally, called celite); :C4AF: Brownmillerite (4CaO·Al2O3·Fe2O3). The silicates are responsible for the cement's mechanical properties — the tricalcium aluminate and brownmillerite are essential for the formation of the liquid phase during the sintering (firing) process of clinker at high temperature in the kiln.
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The converse is also true: if a vapor with components at certain concentrations or partial pressures is in vapor–liquid equilibrium with its liquid, then the component concentrations in the liquid will be determined dependent on the vapor concentrations and on the temperature. The equilibrium concentration of each component in the liquid phase is often different from its concentration (or vapor pressure) in the vapor phase, but there is a relationship. The VLE concentration data can be determined experimentally, approximated with the help of theories such as Raoult's law, Dalton's law, and Henry's law. Such vapor–liquid equilibrium information is useful in designing columns for distillation, especially fractional distillation, which is a particular specialty of chemical engineers.
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Light microscopic picture of a PMMA-copolymer, made by suspension polymerization SEM-Picture of PMMA-particles, that started to coalesce during suspension polymerization, close to a single bead SEM-picture of a Pac-Man shaped PMMA-copolymer particle, made by suspension polymerization Suspension polymerization is a heterogeneous radical polymerization process that uses mechanical agitation to mix a monomer or mixture of monomers in a liquid phase, such as water, while the monomers polymerize, forming spheres of polymer. This process is used in the production of many commercial resins, including polyvinyl chloride (PVC), a widely used plastic, styrene resins including polystyrene, expanded polystyrene, and high-impact polystyrene, as well as poly(styrene-acrylonitrile) and poly(methyl methacrylate).
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Additionally, APCI can often be performed in a modified ESI source. The ionization occurs in the gas phase, unlike ESI, where the ionization occurs in the liquid phase. A potential advantage of APCI is that it is possible to use a nonpolar solvent as a mobile phase solution, instead of a polar solvent, because the solvent and molecules of interest are converted to a gaseous state before reaching the corona discharge needle. Because of APCI involves a gas- phase chemistry, there is no need to use special conditions such as solvents, conductivity, pH for LC. APCI appeared to be more versatile LC/MS interface and more compatible with reversed-phase LC than ESI.
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Liquid phase Epitaxy Semiconducting III–V compounds, acousto-electric effect and free carrier absorption, Gini ratio and Si coefficient related to hot-electron galvanomagnetic transport were some of the other areas of his research. He contributed to the development of electron transport theory related to semiconductors and developed a Monte Carlo method for the computation of coefficients related to velocity correlation, diffusion and noise parameters. His body of work is reported to have relevance to the fields of microwave communications and radar, especially in the development of microwave semiconductor devices. His studies have been documented by way of a number of articles and the article repository of the Indian Academy of Sciences has listed 190 of them.
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Figure 1. Common head groups include thiols, silanes, phosphonates, etc. Figure 1. Representation of a SAM structure SAMs are created by the chemisorption of "head groups" onto a substrate from either the vapor or liquid phase followed by a slow organization of "tail groups". Initially, at small molecular density on the surface, adsorbate molecules form either a disordered mass of molecules or form an ordered two-dimensional "lying down phase", and at higher molecular coverage, over a period of minutes to hours, begin to form three-dimensional crystalline or semicrystalline structures on the substrate surface. The "head groups" assemble together on the substrate, while the tail groups assemble far from the substrate.
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Recent work indicates that both of these complexes represent ideal structures in a more general hydrogen bond network defect. Isolation of the hydronium ion monomer in liquid phase was achieved in a nonaqueous, low nucleophilicity superacid solution (). The ion was characterized by high resolution nuclear magnetic resonance. A 2007 calculation of the enthalpies and free energies of the various hydrogen bonds around the hydronium cation in liquid protonated water at room temperature and a study of the proton hopping mechanism using molecular dynamics showed that the hydrogen-bonds around the hydronium ion (formed with the three water ligands in the first solvation shell of the hydronium) are quite strong compared to those of bulk water.
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CrystaSulf is the trade name for a chemical process used for removing hydrogen sulfide (H2S) from natural gas, synthesis gas and other gas streams in refineries and chemical plants.CrystaSulf – One-Step H2S to Sulfur Conversion for High-Pressure Natural Gas CrystaSulf uses a modified liquid-phase Claus reaction to convert the hydrogen sulfide (H2S) into elemental sulfur which is then removed from the process by filtration. CrystaSulf is used in the energy industry as a mid-range process to handle sulfur amounts between 0.1 and 20 tons per day. Below 0.1 tons of sulfur per day is typically managed by H2S Scavengers and applications above 20 tons per day are typically treated with the Amine – Claus process.
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The eutectic temperature of these brines allows its permanence in liquid state under the registered Martian environmental conditions in the study area of Curiosity, close to the equator, where they are the least favourable for this to happen. Therefore, it is expected that the phenomenon is more intense in terms of duration of the liquid phase in higher latitudes. The presence of liquid water on present day Mars entails transcendent consequences in a number of aspects of the planet's exploration. Firstly, it casts a new light on the comprehension of Martian environment, and can be the key to understand some morphological features of the surface, such as the so-called Recurrent Slope Lineae (RSLs).
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The first step is liquid-phase isomerization using alkaline alumina catalyst leading to internal double bonds. For example, 1-octene is converted to 4-octene and 1-eicocene (a C20 hydrocarbon) is converted to 10-eicocene. In the second step olefin metathesis converts mixtures like these to 2-tetradecene which is a C14 component and again within commercial range. The internal olefins can also be reacted with an excess of ethylene with rhenium(VII) oxide supported on alumina as catalyst in an ethenolysis reaction, which causes the internal double bond to break up to form a mixture of α-olefins with odd and even carbon chain-length of the desired molecular weight.
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His research group developed the open- source Reaction Mechanism Generator software, which allows anyone to rapidly construct accurate kinetic models for many gas-phase and some liquid phase reaction systems. Most of the parameter values in this software come from quantum chemistry calculations, many performed by Green's group at MIT. Although there were many related prior works that laid the groundwork, the Reaction Mechanism Generator was a significant advance over the prior state of the art, making it much easier to construct reliable chemical kinetic models for complicated systems. This is a key part in achieving the long-term goal of many researchers to make it possible to predict what will happen in chemical reactions before doing any experiments.
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Dry ice is the solid form of carbon dioxide (CO2), a molecule consisting of a single carbon atom bonded to two oxygen atoms. Dry ice is colorless, non-flammable, with a sour zesty odor, and can lower the pH of a solution when dissolved in water, forming carbonic acid (H2CO3). Comparison of phase diagrams of carbon dioxide (red) and water (blue) as a log-lin chart with phase transitions points at 1 atmosphere At pressures below 5.13 atm and temperatures below (the triple point), CO2 changes from a solid to a gas with no intervening liquid form, through a process called sublimation.Above the triple point, CO2 goes through the more familiar transitions via a liquid phase.
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Sublimation (phase transition) is the transition of a substance directly from the solid to the gas phase without passing through an intermediate liquid phase. Sublimation is an endothermic phase transition that occurs at temperatures and pressures below a substance's triple point in its phase diagram. In this case, ink is transferred to a base layer, fibreglass for example, through heat and pressure, the result is a full color graphic that will not come off as easily as the more common heat transfers. This application is often found with bamboo boards and composite construction longboards where fibreglass can allow for various degrees of flex or stiffness depending on the ride you're looking for, cruising and carving versus slalom and downhill.
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It generally uses Ruthenium complexes, especially [Ru (Bpy)3]2+ (which releases a photon at ~620 nm) regenerating with TPrA (Tripropylamine) in liquid phase or liquid–solid interface. It can be used as monolayer immobilized on an electrode surface (made e.g. of nafion, or special thin films made by Langmuir–Blogett technique or self-assembly technique) or as a coreactant or more commonly as a tag and used in HPLC, Ru tagged antibody based immunoassays, Ru Tagged DNA probes for PCR etc., NADH or H2O2 generation based biosensors, oxalate and organic amine detection and many other applications and can be detected from picomolar sensitivity to dynamic range of more than six orders of magnitude.
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The chromate coating process starts with a redox reaction between the hexavalent chromium and the metal. In the case of aluminum, for example, : + 0 → + These ions react with hydroxide ions in the water to form hydroxides : + 3 → : + 3 → Under appropriate conditions, these hydroxides will condense with elimination of water to form a colloidal sol of very small particles, that are deposited as a hydrogel on the metal's surface. The gel consists of a three-dimensional solid skeleton of oxides and hydroxides, with nanoscale elements and voids, enclosing a liquid phase. The structure of the gel depends on metal ion concentration, pH, and other ingredients of the solution, such as chelating agents and counterions.
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Although the ability of ice to reject suspended particles in the growth process has long been known, the mechanism remains the subject of some discussion. It was believed initially that during the moments immediately following the nucleation of the ice crystals, particles are rejected from the growing planar ice front, leading to the formation of a constitutionally super-cooled zone directly ahead of the growing ice. This unstable region eventually results in perturbations, breaking the planar front into a columnar ice front, a phenomenon better known as a Mullins-Serkerka instability. After the breakdown, the ice crystals grow along the temperature gradient, pushing ceramic particles from the liquid phase aside so that they accumulate between the growing ice crystals.
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Sondhi has worked extensively across a wide range of topics in theoretical condensed matter physics, notably in the areas of topological phases of matter, strongly correlated electrons, and quantum magnetism. His recent research activity focuses on the study of many-body quantum dynamics. Sondhi's most significant contributions include the discovery of skyrmions in the quantum Hall effect (with A. Karlhede, S. Kivelson and E. Rezayi), the identification of a resonating valence bond liquid phase in the triangular lattice quantum dimer model (with R. Moessner), the theoretical prediction of magnetic monopoles in spin ice (with C. Castelnovo and R. Moessner), and for proposing the \pi-spin glass/time crystal state of periodically driven (Floquet) systems (with V. Khemani, A. Lazarides and R. Moessner).
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In thermodynamics and chemical engineering, the vapor–liquid equilibrium (VLE) describes the distribution of a chemical species between the vapor phase and a liquid phase. The concentration of a vapor in contact with its liquid, especially at equilibrium, is often expressed in terms of vapor pressure, which will be a partial pressure (a part of the total gas pressure) if any other gas(es) are present with the vapor. The equilibrium vapor pressure of a liquid is in general strongly dependent on temperature. At vapor–liquid equilibrium, a liquid with individual components in certain concentrations will have an equilibrium vapor in which the concentrations or partial pressures of the vapor components have certain values depending on all of the liquid component concentrations and the temperature.
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In July 2020 scientists reported that they have transformed the abundant diamagnetic material into a ferromagnetic one by inducing voltage, which may lead to applications in devices such as solar cells or magnetic data storage. Researchers at Trinity University Dublin, Ireland have demonstrated that FeS2 can be exfoliated into few-layers just like other two-dimensional layered materials such as graphene by a simple liquid-phase exfoliation route. This is the first study to demonstrate the production of non-layered 2D-platelets from 3D bulk FeS2. Furthermore, they have used these 2D-platelets with 20% single walled carbon-nanotube as an anode material in lithium-ion batteries, reaching a capacity of 1000 mAh/g close to the theoretical capacity of FeS2.
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A liquid–liquid critical point (or LLCP) is the endpoint of a liquid–liquid phase transition line (LLPT); it is a critical point where two types of local structures coexist at the exact ratio of unity. This hypothesis was first developed by H. Eugene Stanley to obtain a quantitative understanding of the huge number of anomalies present in water. Near a liquid–liquid critical point, there is always a mixture of two alternative local structures. For instance, in supercooled water, two types of local structures exist: a low- density liquid (LDL) and a high-density liquid (HDL), so above the critical pressure, a higher fraction of HDL exists, while below the critical pressure a higher fraction of LDL is present.
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The specific heat has characteristic discontinuities at the glass transition temperature which are caused by the absence in the glassy state of percolating clusters made of broken bonds (configurons) that are present only in the liquid phase. Above the glass transition temperature percolating clusters formed by broken bonds enable a more floppy structure and hence a larger degree of freedom for atomic motion which results in a higher heat capacity of liquids. Below the glass transition temperature there are no extended clusters of broken bonds and the heat capacity is smaller because the solid-state (glassy) structure of amorphous material is more rigid. The discontinuities in the heat capacity are typically used to detect the glass transition temperature where a supercooled liquid transforms to a glass.
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To achieve densification at lower temperatures, several techniques can be employed: additives such as SiC can be used in order to form a liquid phase at the sintering temperature, the surface oxide layer can be removed, or the defect concentration can be increased. SiC can react with the surface oxide layer in order to provide diboride surfaces with higher energy: adding 5–30 vol% SiC has demonstrated improved densification and oxidation resistance of UHTCs. SiC can be added as a powder or a polymer to diboride UHTCs. The addition of SiC as a polymer has several advantages over the more traditional addition of SiC as a powder because SiC forms along the grain boundaries when added as a polymer, which increases measures of fracture toughness (by ~24%).
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Liquid air has a density of approximately 870 kg/m3 (0.87 g/cm3), though the density may vary depending on the elemental composition of the air. Since dry gaseous air contains approximately 78% nitrogen, 21% oxygen, and 1% argon, the density of liquid air at standard composition is calculated by the percentage of the components and their respective liquid densities (see liquid nitrogen and liquid oxygen). Although air contains trace amounts of carbon dioxide (about 0.040%), carbon dioxide solidifies from the gas phase without passing through the intermediate liquid phase, and hence will not be present in liquid air at pressures less than 5.1 atmospheres. The boiling point of liquid air is -194.35 °C (78.80 K), intermediate between the boiling points of liquid nitrogen and liquid oxygen.
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This would allow gas turbines to operate at higher temperatures, which may result in increasing engine thrust by as much as 25%, while reducing fuel usage by 10%. His research on polymer derived ceramic and carbon nanotube composite thermal absorber coatings has been highlighted in National Institute of Standards and Technology (NIST) technical beat. Singh's research on liquid phase exfoliation of 2-D crystals to generate atomically thin sheets of graphene oxide, tungsten and molybdenum disulfide for high capacity metal-ion batteries has appeared in top journals, including American Chemical Society and Nature. Singh is the recipient of the National Science Foundation CAREER Awards for his research on two- dimensional transition metal dichalcogenide and graphene materials for rechargeable metal-ion batteries.
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Melamine was first synthesized by the German chemist Justus von Liebig in 1834. In early production, first calcium cyanamide was converted into dicyandiamide, which was heated above its melting temperature to produce melamine. Today most industrial manufacturers use urea in the following reaction to produce melamine: : 6 (NH2)2CO → C3H6N6 \+ 6 NH3 \+ 3 CO2 In the first step, urea decomposes into cyanic acid and ammonia: : (NH2)2CO → HNCO + NH3 Cyanic acid polymerizes to cyanuric acid, which condenses with the liberated ammonia forming melamine. The released water reacts with cyanic acid, which helps to drive the reaction: : 6 HNCO + 3 NH3 → C3H6N6 \+ 3 CO2 \+ 3NH3 The above reaction can be carried out by either of two methods: catalyzed gas-phase production or high pressure liquid-phase production.
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The principle is that the segregation coefficient k (the ratio of an impurity in the solid phase to that in the liquid phase) is usually less than one. Therefore, at the solid/liquid boundary, the impurity atoms will diffuse to the liquid region. Thus, by passing a crystal boule through a thin section of furnace very slowly, such that only a small region of the boule is molten at any time, the impurities will be segregated at the end of the crystal. Because of the lack of impurities in the leftover regions which solidify, the boule can grow as a perfect single crystal if a seed crystal is placed at the base to initiate a chosen direction of crystal growth.
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JEOL transmission and scanning electron microscope made in the mid-1970s Electron microscopes are expensive to build and maintain, but the capital and running costs of confocal light microscope systems now overlaps with those of basic electron microscopes. Microscopes designed to achieve high resolutions must be housed in stable buildings (sometimes underground) with special services such as magnetic field canceling systems. The samples largely have to be viewed in vacuum, as the molecules that make up air would scatter the electrons. An exception is liquid-phase electron microscopy using either a closed liquid cell or an environmental chamber, for example, in the environmental scanning electron microscope, which allows hydrated samples to be viewed in a low- pressure (up to ) wet environment.
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Enzymatic hydrolysis similar to the body's natural digestive process provides the most efficient breakdown of the proteins into smaller fractions termed peptides which can then be separated from the oil and non-digested proteins during liquid phase processing. Subsequent steps of solids and oil removal through various mechanical separation techniques are required to create a final fish protein fraction with acceptable organoleptic properties for use in human food. Minimization of odor through the elimination of fat and oil from the protein fraction, as well as separating out the lowest molecular weight protein fractions from the larger fractions all serve to create a refined fish protein. Some processes utilize solvents to extract the fat but these can result in dangerous handling and potential residual issues.
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Schematic representation of the different stages and routes of the sol–gel technology In this chemical procedure, a "sol" (a colloidal solution) is formed that then gradually evolves towards the formation of a gel-like diphasic system containing both a liquid phase and solid phase whose morphologies range from discrete particles to continuous polymer networks. In the case of the colloid, the volume fraction of particles (or particle density) may be so low that a significant amount of fluid may need to be removed initially for the gel-like properties to be recognized. This can be accomplished in any number of ways. The simplest method is to allow time for sedimentation to occur, and then pour off the remaining liquid.
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The pressure and temperature at the test separator should be the same as at the wet gas flow meter or the gas and liquid flow rates must be corrected for the conditions at the meter as phases could be different from those measured. Sampling is where a sample of the wet gas is removed from the pipe line for analysis to determine the constituent components. It is important that a sample is collected that is representative of both the gas and liquid phase fractions and that there is no mass transfer between the phases during sampling. Tracer method involves injecting a tracer dye into the wet gas flow and then sampling at a specific distance down stream to measure the dilution of the dye.
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Pyrrolidine is prepared industrially by the reaction of 1,4-Butanediol and ammonia at a temperature of 165–200 °C and a pressure of 17–21 MPa in the presence of a cobalt- and nickel oxide catalyst, which is supported on alumina. :Reaction of 1,4-butanediol with ammonia to form pyrrolidine and water in the presence of a nickel oxide catalyst supported on alumina The reaction is carried out in the liquid phase in a continuous tube- or tube bundle reactor, which is operated in the cycle gas method. The catalyst is arranged as a fixed-bed and the conversion is carried out in the downflow mode. The product is obtained after multistage purification and separation by extractive and azeotropic distillation.
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As the substance in a liquid body crosses the boundary from liquid to gas (see green arrow in phase diagram), the liquid changes into gas at a finite rate, while the amount of liquid decreases. When this happens within a heterogeneous environment, surface tension in the liquid body pulls against any solid structures the liquid might be in contact with. Delicate structures such as cell walls, the dendrites in silica gel, and the tiny machinery of microelectromechanical devices, tend to be broken apart by this surface tension as the liquid–gas–solid junction moves by. To avoid this, the sample can be brought via two possible alternate paths from the liquid phase to the gas phase without crossing the liquid–gas boundary on the phase diagram.
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Dynabeads were developed after John Ugelstad managed to create uniform polystyrene spherical beads (defined as microbeads) of exactly the same size,J. Ugelstad & F.K. Hansen, Rubber Chem. and Techn. 49, 536 - 609 (1976). "Kinetics and mechanism of emulsion polymerization." at the University of Trondheim, Norway in 1976, something otherwise only achieved by NASA in the weightless conditions of SkyLab. Dynabeads are typically 1 to 5 micrometers in diameter. This is in contrast to the Magnetic-activated cell sorting beads, which are approximately 50 nm. This discovery revolutionised the liquid-phase kinetic separation of many biological materials. The technology behind the beads, called Dynabeads, was licensed to Dyno Industrier in 1980 and this magnetic separation technology has been since used for the isolation and manipulation of biological material, including cells, nucleic acids, proteins and pathogenic microorganisms.
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When methanol and carbon monoxide are combined in the presence of a strong base, the result is methyl formate, according to the chemical equation: :CH3OH + CO → HCO2CH3 In industry, this reaction is performed in the liquid phase at elevated pressure. Typical reaction conditions are 80 °C and 40 atm. The most widely used base is sodium methoxide. Hydrolysis of the methyl formate produces formic acid: :HCO2CH3 \+ H2O → HCOOH + CH3OH Efficient hydrolysis of methyl formate requires a large excess of water. Some routes proceed indirectly by first treating the methyl formate with ammonia to give formamide, which is then hydrolyzed with sulfuric acid: :HCO2CH3 \+ NH3 → HC(O)NH2 \+ CH3OH :2 HC(O)NH2 \+ 2H2O + H2SO4 → 2HCO2H + (NH4)2SO4 A disadvantage of this approach is the need to dispose of the ammonium sulfate byproduct.
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Scheme of a trickle-bed reactor A trickle-bed reactor (TBR) is a chemical reactor that uses the downward movement of a liquid and the downward (co- current) or upward (counter-current) movement of gas over a packed bed of (catalyst) particles. It is considered to be the simplest reactor type for performing catalytic reactions where a gas and liquid (normally both reagents) are present in the reactor and accordingly it is extensively used in processing plants. Typical examples are liquid-phase hydrogenation, hydrodesulfurization, and hydrodenitrogenation in refineries (three phase hydrotreater) and oxidation of harmful chemical compounds in wastewater streams or of cumene in the cumene process. Also in the treatment of waste water trickle bed reactors are used where the required biomass resides on the packed bed surface.
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Soil vapor extraction (SVE) is a physical treatment process for in situ remediation of volatile contaminants in vadose zone (unsaturated) soils (EPA, 2012). SVE (also referred to as in situ soil venting or vacuum extraction) is based on mass transfer of contaminant from the solid (sorbed) and liquid (aqueous or non-aqueous) phases into the gas phase, with subsequent collection of the gas phase contamination at extraction wells. Extracted contaminant mass in the gas phase (and any condensed liquid phase) is treated in aboveground systems. In essence, SVE is the vadose zone equivalent of the pump-and-treat technology for groundwater remediation. SVE is particularly amenable to contaminants with higher Henry’s Law constants, including various chlorinated solvents and hydrocarbons. SVE is a well-demonstrated, mature remediation technologyHutzler, N.J., B.E. Murphy, and J.S. Gierke. 1990.
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By combining the above equation with px(σ) for a solute x, and adding the σ-independent combinatorial and dispersive contributions, the chemical potential for a solute X in a solvent S results in: In analogy to activity coefficient models used in chemical engineering, such as NRTL, UNIQUAC or UNIFAC, the final chemical potential can be split into a combinatorial and a residual (non ideal) contribution. The interaction energies Eint(σ,σ') of two surface pieces are the crucial part for the final performance of the method and different formulations are used within the various implementations. In addition to the liquid phase terms a chemical potential estimate for the ideal gas phase µgas has been added to COSMO-RS to enable the prediction of vapor pressure, free energy of solvation and related quantities.
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As water cannot retain its liquid phase in the lunar environment because of its own vapour pressure and the ultra-high vacuum prevailing there, it can be found in solid (ice) and gaseous (vapour) phases. While the Moon Mineralogy Mapper (M3), a payload by NASA, on board Chandrayaan I lunar orbiter has detected, by mapping almost 97% of the lunar surface using remote sensing techniques, the presence of water in ice form in higher latitudes especially in the polar caps, the CHACE payload in the lunar impactor (MIP) has directly detected water in its gaseous form along 14 degree E meridian from 45 degree N to 90 degree S latitude, with a latitudinal resolution of around 0.10 and altitudinal resolution of ~ 250 m from 98 km altitude till impact .
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Porphyry mineral deposits are formed when two plate tectonic plates collide in an advanced subduction zone, then cools off reacting with existing rocks and finally forming a copper deposit. The level of displacement is usually shallow at less than two kilometers below surface in an active volcanic area. An example for a typical arc-island porphyry deposit is described as follows: # The formation starts during early volcanism on the seafloor above a subduction zone in an oceanic-oceanic collision zone # Then as the magma crystallizes, volatiles such as water, carbon dioxide and sulfur dioxide increase in concentration in the liquid phase of the magma. # Eventually, at a very late stage of crystallization, the volatile concentration becomes so great that a separate hydrothermal fluid phase separated from the silicate magma.
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It is available via its traditional derivation (a mechanical equation of state), or via a derivation based in statistical thermodynamics, the latter of which provides the partition function of the system and allows thermodynamic functions to be specified. It successfully approximates the behavior of real fluids above their critical temperatures and is qualitatively reasonable for their liquid and low-pressure gaseous states at low temperatures. However, near the phase transitions between gas and liquid, in the range of p, V, and T where the liquid phase and the gas phase are in equilibrium, the van der Waals equation fails to accurately model observed experimental behaviour, in particular that p is a constant function of V at given temperatures. As such, the van der Waals model is not useful only for calculations intended to predict real behavior in regions near the critical point.
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He was Executive Managing Director of Max-Planck-Institute for Metals Research in Stuttgart and also Professor at the Universities of Stuttgart and Berlin, where he taught courses in equilibrium phase diagrams and powder metallurgy; he is now retired. His main scientific interests dealt with problems in the field of physical metallurgy, powder metallurgy, special ceramics and phase diagrams of metallic and ceramic materials. He is the author and co-author of more than 600 research papers, 10 books, and holds 27 patents. Some of his most important papers and publications are on phase equilibria between intermetallic compounds to the knowledge of peritectic reactions, constitution and properties of cermets, metallography, high-temperature materials, Beryllium and its compounds, liquid phase sintering, particle rearrangement, metallographic etching, toughening of ceramics, Sialon ceramics, sintering of Si3N4 ceramics, metal-ceramic interfaces and processing of advanced ceramics.
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170pxBatch chromatography Binding to the solid phase may be achieved by column chromatography whereby the solid medium is packed onto a column, the initial mixture run through the column to allow settling, a wash buffer run through the column and the elution buffer subsequently applied to the column and collected. These steps are usually done at ambient pressure. Alternatively, binding may be achieved using a batch treatment, for example, by adding the initial mixture to the solid phase in a vessel, mixing, separating the solid phase, removing the liquid phase, washing, re-centrifuging, adding the elution buffer, re-centrifuging and removing the elute. Sometimes a hybrid method is employed such that the binding is done by the batch method, but the solid phase with the target molecule bound is packed onto a column and washing and elution are done on the column.
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When the liquid forms an interface with a gas phase, a molecule on the border has quite different physical properties due to the unbalance of attracting forces by the neighboring molecules. At the equilibrium state of the liquid, interior molecules are under the balanced forces with uniformly distributed adjacent molecules. However, relatively fewer number of molecules in the gas phase above the interface than condensed liquid phase makes overall sum of forces applied to the surface molecule direct inside of the liquid and thus surface molecules tend to minimize their own surface area. Such an inequality of molecular forces induces continuous movement of molecules from the inside to the surface, which means the surface molecules has extra energy, which is called surface free energy or potential energy, and such an energy acting on reduced unit area is defined as surface tension.
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The concept of habitable zones was further developed in 1964 by Stephen H. Dole in his book Habitable Planets for Man, in which he discussed the concept of circumstellar habitable zone as well as various other determinants of planetary habitability, eventually estimating the number of habitable planets in the Milky Way to be about 600 million. At the same time, science-fiction author Isaac Asimov introduced the concept of a circumstellar habitable zone to the general public through his various explorations of space colonization. The term "Goldilocks zone" emerged in the 1970s, referencing specifically a region around a star whose temperature is "just right" for water to be present in the liquid phase. In 1993, astronomer James Kasting introduced the term "circumstellar habitable zone" to refer more precisely to the region then (and still) known as the habitable zone.
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Air Pollution Control Orientation Course from website of the Air Pollution Training InstituteEnergy savings in steam systems Figure 3a, Layout of surface condenser (scroll to page 11 of 34 PDF pages) To conserve energy and cooling capacity in chemical and other plants, regenerative heat exchangers can transfer heat from a stream that must be cooled to another stream that must be heated, such as distillate cooling and reboiler feed pre-heating. This term can also refer to heat exchangers that contain a material within their structure that has a change of phase. This is usually a solid to liquid phase due to the small volume difference between these states. This change of phase effectively acts as a buffer because it occurs at a constant temperature but still allows for the heat exchanger to accept additional heat.
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Sticking coefficient is the term used in surface physics to describe the ratio of the number of adsorbate atoms (or molecules) that adsorb, or "stick", to a surface to the total number of atoms that impinge upon that surface during the same period of time.sticking coefficient IUPAC Compendium of Chemical Terminology 2nd Edition (1997), Accessed 30 September 2008 Sometimes the symbol Sc is used to denote this coefficient, and its value is between 1 (all impinging atoms stick) and 0 (no atoms stick). The coefficient is a function of surface temperature, surface coverage (θ) and structural details as well as the kinetic energy of the impinging particles. The original formulation was for molecules adsorbing from the gas phase and the equation was later extended to adsorption from the liquid phase by comparison with molecular dynamics simulations.
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Soda lime glass bottles Majumdar used scattering theory techniques to study bound magnon states, and his findings have since been experimentally verified. He modified the work of Michael R. Douglas and Sam Edwards on soda-lime glass and proposed a simpler explanation for its time-dependent stress relaxation and a formula to assess long time scales with regard to its order of magnitude. Some of his other achievements include the calculation of critical isotherm of Lennard- Jones gas, the Mössbauer effect determination of the Fe(II) and Fe(III) ratio, the determination of critical parameters of gas-liquid phase transition, the Ising model of ferromagnetism, and the development of a theoretical method for measuring the Fermi momentum of metals. His studies have been documented by way of a number of articles and the article repository of the Indian Academy of Sciences has listed 45 of them.
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The temperature dependence of the soil hydraulic properties was included by considering the effects of temperature on surface tension, dynamic viscosity and the density of water. The heat transport equation in CHAIN_2D considered transport due to conduction and advection with flowing water. The solute transport equations considered advective-dispersive transport in the liquid phase, as well as diffusion in the gaseous phase. The transport equations also included provisions for nonlinear nonequilibrium reactions between the solid and liquid phases, linear equilibrium reactions between the liquid and gaseous phase, zero-order production and two first- order degradation reactions: one which was independent of other solutes, and one which provided the coupling between solutes involved in the sequential first-order decay reactions. The SWMS_2D and CHAIN_2D models formed the bases of versions 1.0 (for 16-bit Windows 3.1) and 2.0 (for 32-bit Windows 95) of HYDRUS-2D (Šimůnek et al.
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The total heat capacity of a mole of water in its liquid phase (the green line) is 7.5507 kJ. At one specific thermodynamic point, the melting point (which is 0 °C across a wide pressure range in the case of water), all the atoms or molecules are, on average, at the maximum energy threshold their chemical bonds can withstand without breaking away from the lattice. Chemical bonds are all-or-nothing forces: they either hold fast, or break; there is no in-between state. Consequently, when a substance is at its melting point, every joule of added thermal energy only breaks the bonds of a specific quantity of its atoms or molecules,Water's enthalpy of fusion (0 °C, 101.325 kPa) equates to per molecule so adding one joule of thermal energy to 0 °C water ice causes water molecules to break away from the crystal lattice and become liquid.
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This is characterized by the following quantities: B_o is an oil formation volume factor (ratio of some volume of reservoir liquid to the volume of oil at standard conditions obtained from the same volume of reservoir liquid), B_w is a water formation volume factor (ratio of volume of water at reservoir conditions to volume of water at standard conditions), B_g is a gas formation volume factor (ratio of some volume of reservoir vapor to the volume of gas at standard conditions obtained from the same volume of reservoir vapor), R_S is a solution of gas in oil phase (ratio of volume of gas to the volume of oil at standard conditions obtained from some amount of liquid phase at reservoir conditions), R_V is a vaporized oil in gas phase (ratio of volume of oil to the volume of gas at standard conditions obtained from some amount of vapor phase at reservoir conditions).
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Before starting the construction and use of a McCabe–Thiele diagram for the distillation of a binary feed, the vapor–liquid equilibrium (VLE) data must be obtained for the lower-boiling component of the feed. Figure 1: Typical McCabe–Thiele diagram for distillation of a binary feed The first step is to draw equal sized vertical and horizontal axes of a graph. The horizontal axis will be for the mole fraction (denoted by x) of the lower-boiling feed component in the liquid phase. The vertical axis will be for the mole fraction (denoted by y) of the lower-boiling feed component in the vapor phase. The next step is to draw a straight line from the origin of the graph to the point where x and y both equal 1.0, which is the x = y line in Figure 1. This 45 degree line is used simply as a graphical aid for drawing the remaining lines.
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Class 3: Flammable Liquids A flammable liquid is a liquid having a flash point of not more than 60 °C (140 °F), or any material in a liquid phase with a flash point at or above 37.8 °C (100 °F) that is intentionally heated and offered for transportation or transported at or above its flash point in a bulk packaging. The following exceptions apply: #Any liquid meeting one of the definitions specified in 49CFR 173.115. #Any mixture having one or more components with a flash point of 60.5 °C (141 °F) or higher, that make up at least 99 percent of the total volume of the mixture, if the mixture is not offered for transportation or transported at or above its flash point. #Any liquid with a flash point greater than 35 °C (95 °F) which does not sustain combustion according to ASTM 4206 or the procedure in Appendix H of this part.
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In Grenoble, he set up in 1959 at the master level a new syllabus in general geophysics which will flourish in the 1960s when the Earth's sciences will be refounded by the plate tectonics "theory". Two articles published in 1969 and 1970 on the modelling of convection within the Earth's mantle showed him, with Claude Allègre, Xavier Le Pichon and Dan McKenzie, in the very closed circle of European scientists at the leading edge of the new theory. He was the first to notice that the viscosity of the asthenosphere, due to partial melting (of the order of one percent), is analogous to what happens in so-called "temperate glaciers" where ice is also partially melted in the same order of magnitude, with the coexistence of a liquid phase and a solid phase. He also modelled the postglacial rebound of the lithosphere as observed in Fennoscandia or Canada following the disappearance of Quaternary ice caps, which allowed him to infer the mechanical properties of the Earth's mantle, its rheology and its viscosity.
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In practice it is unlikely that people would simply sit and wait for nuclear decay to go to completion, as in all historical fallout cases, decontamination of valuable land has occurred. This is most commonly done with the use of simple equipment such as lead glass covered excavators and bulldozers, similar to those employed in the Lake Chagan project. By skimming off the thin layer of fallout on the topsoil surface and burying it in the likes of a deep trench along with isolating it from ground water sources, the gamma air dose is cut by orders of magnitude.International Atomic Energy Agency International Atomic Enmergy Agency, 2000 - Technology & Engineering - restoration of environments with radioactive residues : papers and discussions, 697 pages The decontamination after the Goiânia accident in Brazil in 1987 and the possibility of a "dirty bomb" with Co-60, which has similarities with the environment that one would be faced with after a nuclear yielding cobalt bomb's fallout had settled, has prompted the invention of "Sequestration Coatings" and cheap liquid phase sorbents for Co-60 that would further aid in decontamination, including that of water.
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