Magnetic refrigeration

Many elements and compounds do not present an electronic magnetic moment, but their nuclei possess nuclear magnetic moments. These moments can be used for a magnetic refrigeration as it is done with electronic moments. Also in this case the minimum temperature, now in the microkelvin range, is reached when the spontaneous magnetic... 

Various types of work in addition to pV work are frequently involved in experimental studies. Research on chemical equilibria for example may involve surfaces or phases at different electric or magnetic potentials [11], We will here look briefly at field-induced transitions, a topic of considerable interest in materials science. Examples are stress-induced formation of piezoelectric phases, electric polarization-induced formation of dielectrica and field-induced order-disorder transitions, such as for environmentally friendly magnetic refrigeration. 

Bezold—Br eke effect, 7 308 B-form oligonucleotides, 17 606 BHK cell based products, 5 35 It Bhopal disaster, 21 829, 830 BHS-Fest pressure filter, 11 378-379 Bi2223 magnets, refrigerator-cooled,... 

In order to make magnetic refrigeration practical one must use a continuous cyclic process in which heat must be rejected when the ferromagnet experiences a magnetic field increase (just as the heat is rejected during the compression of a gas in a conventional gas cycle... 

Zimm, C, A, Jastrab, A. Stenberg, V. Pecharsky, K. Gsehneidner, Jr., M, Osborne, and I, Anderson, Description and Performance of a Near-room Temperature Magnetic Refrigerator, Adv. Ctyo. Engin. 43. 1759-1766 (1998). 

Magnetic refrigeration offers high thermodynamic efficiencies due to the reversibility of the magneto-caloric effect. For active magnetic regeneration... 

Hall, J.L., J.A. Barclay, Analyzing Magnetic Refrigeration Efficiency A Rotary AMR-Reverse Brayton Case Study , Advances in Cryogenic Engineering, V. 43B, pp. 1719-1728, 1998... 

Barclay, J. A., "Analysis of Liquefaction of Helium Using Magnetic Refrigerators," Technical Report, Los Alamos National Lab., NTIS PC A03/MF A01, National Technical Information Service, Dec. (1981). 

Dysprosium 66 Dy Catalysts, electronic materials, phosphor activators, magnetic refrigeration, magnetostrictive alloys... 

Since the input and output can be interchanged in a symmetrical three dimensional transducer, this interchange principle can be effectively used in magnetic refrigeration. The operating temperature range determines the working material and the Gd Metal is most suitable for ambient conditions. 

W.E. Keller, Magnetic Refrigeration The Basis for a New Refrigeration Technology, LALP-82-34, Los Alamos National Laboratory Report, 1982. 

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