On some factors affecting the nonstoichiometry in U3O8
1981; Elsevier BV; Volume: 97; Issue: 1-2 Linguagem: Inglês
10.1016/0022-3115(81)90422-0
ISSN1873-4820
AutoresTakeo Fujino, Hiroaki Tagawa, Takeo Adachi,
Tópico(s)Nuclear reactor physics and engineering
ResumoThe nonstoichiometry of U3O8 was studied under various conditions. The OU atom ratios obtained by the oxidation of uranium metal in air followed by cooling with moderate rates (method 1) are 2.67 ± 0.01 in the temperature range 700 ~ 900°C and 2.662 ± 0.005 at 1000°C and are generally larger than the ratio by thermogravimetry. If the oxidation was carried out in a crucible with a lid, a compositional peak was observed at 900 ~ 950°C, which did not appear for the U3O8 samples from UO2. The U3O8 made from UO2 by method 1 have OU ratios 2.655 ± 0.005 (700°C), 2.653 ± 0.004 (800°C), 2.648 ± 0.004 (900°C) and 2.645 ± 0.003 (1000°C). Differences were observed in the O/U ratios of heating and cooling series. X-ray diffraction analysis showed several additional peaks other than those of α-U3O8 for the samples which exhibited the compositional peak.
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