Peter Rudolf Wyder (born 26 February 1934) is a Swiss physicist. He was a professor of experimental solid-state physics at the Radboud University Nijmegen in the Netherlands. Wyder later served as director of the High Field Magnet Laboratory in Grenoble, France.
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The Magnet Science and Technology division is charged with developing the technology and expertise for magnet systems. These magnet projects include building advanced magnet systems for the Tallahassee and Los Alamos sites, working with industry to develop the technology to improve high- field magnet manufacturing capabilities, and improving high field magnet systems through research and development. Also at the lab's FSU headquarters, the Applied Superconductivity Center advances the science and technology of superconductivity for both the low temperature niobium-based and the high temperature cuprate or MgB2-based materials. The ASC pursues the superconductors for magnets for fusion, high energy physics, MRI, and electric power transmission lines and transformers.
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Wyder was born on 26 February 1934 in Burgdorf. He obtained his PhD at ETH Zurich in 1965 with a doctoral thesis titled: "Freie Weglängen für die elektrische und die thermische Leitfähigkeit". From 1967 he was a professor of experimental solid-state physics at Radboud University Nijmegen. There he worked with the High Field Magnet Laboratory.
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Formerly considered the world's premier high-field magnet research center, the Laboratory was merged into the Plasma Science and Fusion Center, after the National Science Board decided in 1990 to locate the new National High Magnetic Field Laboratory at Florida State University. MIT appealed this decision unsuccessfully; at the time, this was the first appeal of an NSB decision.
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Wyder was director of the High Field Magnet Laboratory (GHMFL) in Grenoble, France. The laboratory was founded on the basis of cooperation between the Max Planck Institute for Solid State Research and the French National Centre for Scientific Research. Wyder was director of the Max Planck Institute for Solid State Research between 1984 and 2001. He retired as director of the GHMFL in 2001.
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Diamagnetic forces acting upon the water within its body levitating a live frog inside the 3.2 cm vertical bore of a Bitter solenoid at the Nijmegen High Field Magnet Laboratory, Nijmegen, Netherlands. The magnetic field was about 16 teslas. Video is available. A Bitter electromagnet or Bitter solenoid is a type of electromagnet invented in 1933 by American physicist Francis Bitter used in scientific research to create extremely strong magnetic fields.
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EMFL's Logo The European Magnetic Field Laboratory (EMFL)EMFL's Website gathers the efforts of three laboratories in Germany, France, and the Netherlands: the Dresden High Magnetic Field Laboratory (HLD), the Laboratoire National des Champs Magnétiques Intenses (LNCMI) in Grenoble and Toulouse and the High Field Magnet Laboratory (HFML)HFML's Website in Nijmegen. EMFL was an initiative of Prof. Jan Kees Maan, former director of HFML in Nijmegen. Research in the high field magnets of the EMFL leads to new insights in material properties.
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A live frog levitates inside a diameter vertical bore of a Bitter solenoid in a magnetic field of about 16 teslas at the Nijmegen High Field Magnet Laboratory. Diamagnets may be levitated in stable equilibrium in a magnetic field, with no power consumption. Earnshaw's theorem seems to preclude the possibility of static magnetic levitation. However, Earnshaw's theorem applies only to objects with positive susceptibilities, such as ferromagnets (which have a permanent positive moment) and paramagnets (which induce a positive moment).
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Modern software, such as Motor-CAD, can help to increase the thermal efficiency of motors while still in the design stage. Among these types are the disc-rotor types, described in more detail in the next section. The vibrating alert of cellular phones is sometimes generated by tiny cylindrical permanent-magnet field types, but there are also disc-shaped types that have a thin multipolar disc field magnet, and an intentionally unbalanced molded-plastic rotor structure with two bonded coreless coils. Metal brushes and a flat commutator switch power to the rotor coils.
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Doubly-fed electric machines also slip-ring generators are electric motors or electric generators, where both the field magnet windings and armature windings are separately connected to equipment outside the machine. By feeding adjustable frequency AC power to the field windings, the magnetic field can be made to rotate, allowing variation in motor or generator speed. This is useful, for instance, for generators used in wind turbines. DFIG-based wind turbines, because of their flexibility and ability to control active and reactive power, are almost the most interesting wind turbine technology.
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The most powerful electromagnet in the world, the 45T hybrid Bitter-superconducting magnet at the US National High Magnetic Field Laboratory, Tallahassee, Florida, USA The strongest continuous magnetic fields on Earth have been produced by Bitter magnets. the strongest continuous field achieved by a room temperature magnet is 37.5T produced by a Bitter electromagnet at the Radboud University High Field Magnet Laboratory in Nijmegen, Netherlands. The strongest continuous manmade magnetic field, 45T, was produced by a hybrid device, consisting of a Bitter magnet inside a superconducting magnet. The resistive magnet produces 33.5T and the superconducting coil produces the remaining 11.5T.
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This may cause confusion when working with compound machines like brushless alternators, or in conversation among people who are accustomed to work with differently configured machinery. In most generators, the field magnet is rotating, and is part of the rotor, while the armature is stationary, and is part of the stator. Both motors and generators can be built either with a stationary armature and a rotating field or a rotating armature and a stationary field. The pole piece of a permanent magnet or electromagnet and the moving, iron part of a solenoid, especially if the latter acts as a switch or relay, may also be referred to as armatures.
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In order to overcome these limitations, commercial MC-ICP-MS are double-focusing instruments. In a double-focusing mass-spectrometer ions are focused due to kinetic energy by the ESA (electro-static-analyzer) and kinetic energy + mass/charge (momentum) in the magnetic field. Magnet and ESA are carefully chosen to match the energy focusing properties of one another and are arranged so that the direction of energy focusing is in opposite directions. To simplify, two components have an energy focus term, when arranged properly, the energy term cancels out and ions with the same mass/charge ratio focus at the same point in space.
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A pulsed field magnet is a strong electromagnet which is powered by a brief pulse of electric current through its windings rather than a continuous current, producing a brief but strong pulse of magnetic field. Pulsed field magnets are used in research in fields such as materials science to study the effect of strong magnetic fields, since they can produce stronger fields than continuous magnets. The maximum field strength that continuously-powered high- field electromagnets can produce is limited by the enormous waste heat generated in the windings by the large currents required. Therefore by applying brief pulses of current, with time between the pulses to allow the heat to dissipate, stronger currents can be used and thus stronger magnetic fields can be generated.
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The disks are pierced with holes through which cooling water passes to carry away the heat caused by the high current. The strongest continuous field achieved solely with a resistive magnet is 37.5 T , produced by a Bitter electromagnet at the Radboud University High Field Magnet Laboratory in Nijmegen, the Netherlands. The previous record was 35 T. The strongest continuous magnetic field overall, 45 T, was achieved in June 2000 with a hybrid device consisting of a Bitter magnet inside a superconducting magnet. The factor limiting the strength of electromagnets is the inability to dissipate the enormous waste heat, so more powerful fields, up to 100 T, have been obtained from resistive magnets by sending brief pulses of high current through them; the inactive period after each pulse allows the heat produced during the pulse to be removed, before the next pulse.
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1 MT/s is 106 or one million transfers per second; similarly, 1 GT/s means 109, or equivalently in the US/short scale, one billion transfers per second. The choice of the symbol T for transfer conflicts with the International System of Units, in which T stands for the tesla unit of magnetic flux density (so "Megatesla per second" would be a reasonable unit to describe the rate of a rapidly changing magnetic field, such as in a pulsed field magnet or kicker magnet - although the equivalent units of "tesla per microsecond" (T/μs) would reflect typical engineering values better). These terms alone do not specify the bit rate at which binary data is being transferred, because they do not specify the number of bits transferred in each transfer operation (known as the channel width or word length). In order to calculate the data transmission rate, one must multiply the transfer rate by the information channel width. For example, a data bus eight-bytes wide (64 bits) by definition transfers eight bytes in each transfer operation; at a transfer rate of 1 GT/s, the data rate would be 8 × 109 B/s, i.e.
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