Lanthanum thermal properties

Cheng Z, Zha S, Aguilar L, and Liu M. Chemical, electrical, and thermal properties of strontium doped lanthanum vanadate. Solid State Ionics 2005 176 1921-1928. 

Studies on the thermal properties of lanthanum, cerium, neodymium, and gadolinium hexaborides in the cryogenic region from 5° to 350°K. 193) have shown the presence of two types of anomalies in the latter three substances. At temperatures near 10 °K. there appears a lambda-type anomaly in each which is rather characteristic of a magnetic transformation. At slightly higher temperatures this is followed by Schottky-... 

Laboratory reagents, preparation of, 8-1 to 4 Laboratory Solvents and Other Liquid Reagents, 15-13 to 22 Laguerre polynomials, A-83 to 85 Lanthanum see also Elements electrical resistivity, 12-39 to 40 electron configuration, 1-18 to 19 heat capacity, 4-135 history, occurrence, uses, 4-1 to 42 ionization energy, 10-203 to 205 isotopes and their properties, 11-56 to 253 magnetic susceptibility, 4-142 to 147 molten, density, 4-139 to 141 physical properties, 4-133 to 134 thermal properties, 12-201 to 202 vapor pressure, 6-61 to 90 vapor pressure, high temperature, 4-136 to 137... 

Uses. In spite of unique properties, there are few commercial appUcations for monolithic shapes of borides. They are used for resistance-heated boats (with boron nitride), for aluminum evaporation, and for sliding electrical contacts. There are a number of potential uses ia the control and handling of molten metals and slags where corrosion and erosion resistance are important. Titanium diboride and zirconium diboride are potential cathodes for the aluminum Hall cells (see Aluminum and aluminum alloys). Lanthanum hexaboride and cerium hexaboride are particularly useful as cathodes ia electronic devices because of their high thermal emissivities, low work functions, and resistance to poisoning. 

Ding X, Liu Y, Gao L, and Guo L. Effects of cation substitution on thermal expansion and electrical properties of lanthanum chromites. J. Alloys Compounds 2006 425 318-3 22. 

Highly pure lanthanum oxide is used to make optical glass of high refractive index for camera lenses. It also is used to make glass fibers. The oxide also is used to improve thermal and electrical properties of barium and strontium titanates. Other applications are in glass polishes carbon arc electrodes fluorescent type phosphors and as a diluent for nuclear fuels. In such apph-cations, lanthinum oxide is usually combined with other rare earth oxides. 

The rare earth oxides have a number of distinguishing properties important in catalytic applications. The oxides are basic O) compared to alumina, lanthanum oxide (La203) being the most basic. The oxides also have good thermal stability, a valuable characteristic in most industrial applications. Some rare earths including cerium, praseodymium, and terbium form non-stoichiomet-ric oxides ( ), an important property shared by many good oxidation catalysts. These mixed valence state compounds are typically polymorphic. 

Ca, Ba, Sr ) into PT ceramics is reported to enhance the pyroelectric properties. Substitution of these ions results in the reduction of lattice anisotropy leading to hard and dense ceramics with high mechanical strength. From the standpoint of thermal responsivity, the performance of a pyroelectric detector is enhanced when it is in the form of a thin film. In recent device applications, it has become increasingly necessary to consider the improvement of these films in then-performance in addition to the large component area and connection to many circuit elements. Recently, calcium- and lanthanum-doped lead... 

Marina OA, Canfield NL, Stevenson JW (2002) Thermal, electrical, and electrocatalytical properties of lanthanum-doped strontium titanate. Solid State Ionics 149 21... 

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