Fuchsin solutions appear colored due to the visible wavelength absorbance of its central quinoid structure—see also for example viologen —but are "decolorized" upon sulfonation of the dye at its central carbon atom by sulfurous acid or its conjugate base, bisulfite. This reaction disrupts the otherwise favored delocalized extended pi-electron system and resonance in the parent molecule. The structure of the "decolorized" Schiff reagent. The further reaction of the Schiff reagent with aldehydes is complex with several research groups reporting multiple reaction products with model compounds.
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This allows elastin to remain stained, while remaining tissue elements are decolorized. Sodium thiosulfate is used to remove excess iodine and a counterstain (most often Van Gieson's stain) is used to contrast the principal stain.Verhoeff's Elastic Stain. TV Mouse UC Davis.
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Tequila is naturally clear after fermentation and distillation are complete. This type is called “blanco” or “white”. “Plata” or “silver” on the other hand, despite its color being the same as “blanco”, is an aged version of tequila which got decolorized after being kept in barrels for months or years.
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An alternative to this "phosphatation" technique is "carbonatation", which is similar, but uses carbon dioxide and calcium hydroxide to produce a calcium carbonate precipitate. After filtering any remaining solids, the clarified syrup is decolorized by filtration through activated carbon. Bone char or coal-based activated carbon is traditionally used in this role. Some remaining color-forming impurities adsorb to the carbon.
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A selection of differently colored beetroot varieties The red color seen in beeturia is caused by the presence of unmetabolized betalain pigments such as betanin in beetroot passed through the body. The pigments are absorbed in the colon. Betalains are oxidation-sensitive redox indicators that are decolorized by hydrochloric acid, ferric ions, and colonic bacteria preparations. The gut flora play a not-yet-evaluated role in the breakdown of the pigment.
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Orally ingested non-decolorized aloe vera leaf extract was listed by the California Office of Environmental Health Hazard Assessment, along with goldenseal, among "chemicals known to the state to cause cancer or reproductive toxicity". Use of topical aloe vera is not associated with significant side effects. Oral ingestion of aloe vera is potentially toxic, and may cause abdominal cramps and diarrhea which in turn can decrease the absorption of drugs.
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Large Rochelle salt crystal grown aboard Skylab The starting material is tartar with a minimum tartaric acid content 68 %. This is first dissolved in water or in the mother liquor of a previous batch. It is then saponified with hot caustic soda to pH 8, decolorized with activated charcoal, and chemically purified before being filtered. The filtrate is evaporated to 42 °Bé at 100 °C, and passed to granulators in which Seignette's salt crystallizes on slow cooling.
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The sugar solution is clarified by the addition of phosphoric acid and calcium hydroxide, which combine to precipitate calcium phosphate. The calcium phosphate particles entrap some impurities and absorb others, and then float to the top of the tank, where they can be skimmed off. An alternative to this "phosphatation" technique is "carbonatation", which is similar, but uses carbon dioxide and calcium hydroxide to produce a calcium carbonate precipitate. After filtering any remaining solids, the clarified syrup is decolorized by filtration through activated carbon.
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The remaining sugar is then dissolved to make a syrup (about 70 percent by weight solids), which is clarified by the addition of phosphoric acid and calcium hydroxide that combine to precipitate calcium phosphate. The calcium phosphate particles entrap some impurities and absorb others, and then float to the top of the tank, where they are skimmed off. After any remaining solids are filtered out, the clarified syrup is decolorized by filtration through the use of bone char, which is made from the bones of cattle, a bed of activated carbon or, in more modern plants, ion- exchange resin.
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P. vivax and P. ovale sitting in EDTA for more than 30 minutes before the blood film is made will look very similar in appearance to P. malariae, which is an important reason to warn the laboratory immediately when the blood sample is drawn so they can process the sample as soon as it arrives. Microscopically, the parasitised red blood cell (erythrocyte) is never enlarged and may even appear smaller than that of normal red blood cells. The cytoplasm is not decolorized and no dots are visible on the cell surface. The food vacuole is small and the parasite is compact.
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When zircon is heated it sometimes changes in color, or altogether loses it, and at the same time usually increases in density and brilliancy. The so-called Matura diamonds, formerly sent from Matara (or Matura), in Sri Lanka, were decolorized zircons. The zircon has strong refractive power, and its lustre is almost adamantine, but it lacks the fire of the diamond. The specific gravity of zircon is subject to considerable variation in different varieties; thus Sir A. H. Church found the specific gravity of a fine leaf- green jargoon to be as low as 3.982, and that of a pure white jargoon as high as 4.705.
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In the currently accepted mechanism, the pararosaniline and bisulfite combine to yield the "decolorized" adduct with sulfonation at the central carbon as described and shown. The free, uncharged aromatic amine groups then react with the aldehyde being tested to form two aldimine groups; these groups have also been named for their discoverer as Schiff bases (azomethines), with the usual carbinolamine (hemiaminal) intermediate being formed and dehydrated en route to the Schiff base. These electrophilic aldimine groups then react with further bisulfite, and the Ar-NH-CH(R)-SO3− product (and other resonance- stabilized species in equilibrium with the product) give rise to the magenta color of a positive test."Schiffsche Probe" (Schiff test), University of Bayreuth, Bavaria, Germany, accessed 8 March 2013.
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While the average television show would take seven days to shoot, Moonlighting would take from 12–14 days to complete with episodes and dialogue frequently being written by Caron the same day they were shot. This attention to detail contributed to Moonlighting as being one of the most expensive television shows being produced at the time. Where most episodes would cost around $900,000 to produce, Moonlighting was running nearly double that. The season 2 episode "The Dream Sequence Always Rings Twice" could have been filmed much more cheaply by being shot in color and then decolorized, but Caron insisted on the authentic look of black-and-white film which took 16 days to shoot, bringing the cost of the episode to the then-unheard-of sum of two million dollars.
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