Thermal conductivity rare earth elements

Rare earth elements, with relatively high thermal neutron activation cross-sections, have been tested or considered as tagging species for this purpose. At GA (Ref 8), preliminary expts were conducted with 0.38 cal ammo using dysprosium (Dy) and europium (Eu) deposited on the wall of the cartridge case and in the gunpowder, and Dy, hoKnium (Ho) and indium (In) in the primer. 

On the other hand, the use of rare earth metals for the fixing of os gen and sulfur in light metals for production of conductive copper and conductive aluminum has remained insignificant. Hcwever, the use of rare earth elements as magnesium hardeners remains important, tfere the rare earth metals serve precipitation of intermetallic compounds of high thermal stability. 

The title compound has been synthesized by means of degradation. Its composition has been determined by chemieal analysis, TG and ICP. The studies of IR, UV, XRD, W-NMR indicate that the compound has the Keggin structure, and the results of TG-DTA show that the stable temperature of this compound is up to 400-450°C. We also studied the rare earth chemical thermal diffiision of the eomplex and found that the rare earth element can permeate into the surface, interface and the body cavity of the prepared material. The conductivity of the permeated sample is 1.935X 10 Q cm, which is 10 times higher than that of the parent K,oH3[Y(SiW, 039)2]. 

There are only a few papers devoted to investigation of the thermal conductivity of metallic rare earth glasses (Guessons and Mazuer 1982). No peculiarities (compared with standard metallic glasses) have been coimected with the presence of the rare earth elements. The glass behaviour of metallic glasses must display itself in both... 

The examples cited in Section IV are frequently drawn from work carried out in this laboratory. They have been chosen to illuminate file principles involved. The present review is not indended to be exhaustive, but rather illustrative of principles. Because of space limitations many important topics are not included — behaviour of the elemental rare earths (7), amorphous materials (6), liquid rare earth systems (7), elastic and magnetoelastic properties (4), thermal conductivity (4), etc. The reader who is interested in these topics is referred to the reviews cited in ref. (7), (4), (6) and (7). 

The rare earth metals display a rich variety of transport phenomena, which we shall discuss in the remaining sections. Transport properties were last reviewed by Legvold (1972), who presented data for the resistivity, thermal conductivity and Seebeck coefficient of almost all the rare earth metals together with Hall effect results for the elements Gd-Er. Since 1972 little attention has been given to the thermal conductivity and Seebeck coefficient and, accordingly, we shall concentrate on the resistivity, magnetoresistivity and Hall effect measurements, with particular attentiM to recent studies. 

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