1764
KALINNIKOV et al.
amount (about 5 wt % in the case in question) and
sampling for determining the content of Ln O made
lowered to a minimum the contaminating effect of
the apparatus.
2
3
it possible to plot the temperature dependences of the
limiting solubility of the REE oxides. The functions
obtained are described by the equations
ACKNOWLEDGMENTS
The study was carried out in accordance with the
project High-Temperature Chemical and Electro-
chemical Syntheses of New Compounds Based on
Less-Common and Rare-Earth Metals, within the
framework of the integrated program of the Russian
Academy of Sciences.
clim = 0.0015T
clim = 0.0136T
clim = 0.0139T
0.0794 for gadolinium oxide, (9)
8.4549 for yttrium oxide, (10)
0.2602 for neodymium oxide, (11)
where c
is the limiting content of Ln O in the
2 3
REFERENCES
lim
melt (wt %), and T is the temperature of the melt ( C).
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The use of dependences (6) (8) and evaluation of
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tioned REEs made it possible to give preference to
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1998, p. 50.
the hydrofluoride method of LnF preparation in an
3
inert atmosphere [oxygen content of the REE fluoride
4
was (0.12 1.88) 10 mol %].
CONCLUSIONS
(1) Reactions of Y O and Nd O with ammoni-
2
3
2 3
4. Zamoryanskaya, M.V., Petrova, M.A., and Semeno-
va, T.S., Izv. Ross. Akad. Nauk, Neorg. Mater., 1998,
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4
10
mol %. The use of glassy carbon materials
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RUSSIAN JOURNAL OF APPLIED CHEMISTRY Vol. 75 No. 11 2002