TY - JOUR
T1 - Thermodynamics of (Mg,Ce,U)O2+x(x0) solid solutions
AU - Fujino, Takeo
AU - Park, Kwangheon
AU - Sato, Nobuaki
AU - Yamada, Makoto
N1 - Funding Information:
One of the authors, K.P., thanks the Core University Program between Seoul National University and Kyoto University on Energy Science and Engineering, funded by the Japan Society for the Promotion of Science and the Korea Science and Engineering Foundation for the financial support of his research stay in Japan.
PY - 2001/4
Y1 - 2001/4
N2 - Quaternary solid solutions, MgyCezU1-y-zO2+x(x0), were prepared and equilibrated under various oxygen partial pressures. The solubility of magnesium in Ce0.1U0.9O2+x was about y = 0.05, and above this concentration MgO precipitated, forming a two-phase mixture. In MgyCezU1-y-zO2+x with y ≤ 0.05, a part of the dissolved magnesium atoms occupy the interstitial 4b position of Fm3̄m. The ratio of the interstitial magnesium to the total magnesium increases from about 0.3 to 0.6 as the oxygen partial pressure decreases to 10-19-10-21atm. The rates of change of the lattice parameter, ∂a/∂y, ∂a/∂z and ∂a/∂x, for x greater than 0 were somewhat smaller in absolute values than literature values. For x < 0, the rates ∂a/∂z and ∂a/∂x were in good agreement with the literature values. However, ∂a/∂y was much smaller as absolute value due to interstitial magnesium. A plot of oxygen potential vs O/M ratio at 1000°C showed a marked shift to lower x for the MgyCezU1-y-zO2+x solid solution. The shift rate was -0.01 per 1 mol% magnesium.
AB - Quaternary solid solutions, MgyCezU1-y-zO2+x(x0), were prepared and equilibrated under various oxygen partial pressures. The solubility of magnesium in Ce0.1U0.9O2+x was about y = 0.05, and above this concentration MgO precipitated, forming a two-phase mixture. In MgyCezU1-y-zO2+x with y ≤ 0.05, a part of the dissolved magnesium atoms occupy the interstitial 4b position of Fm3̄m. The ratio of the interstitial magnesium to the total magnesium increases from about 0.3 to 0.6 as the oxygen partial pressure decreases to 10-19-10-21atm. The rates of change of the lattice parameter, ∂a/∂y, ∂a/∂z and ∂a/∂x, for x greater than 0 were somewhat smaller in absolute values than literature values. For x < 0, the rates ∂a/∂z and ∂a/∂x were in good agreement with the literature values. However, ∂a/∂y was much smaller as absolute value due to interstitial magnesium. A plot of oxygen potential vs O/M ratio at 1000°C showed a marked shift to lower x for the MgyCezU1-y-zO2+x solid solution. The shift rate was -0.01 per 1 mol% magnesium.
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U2 - 10.1016/S0022-3115(01)00452-4
DO - 10.1016/S0022-3115(01)00452-4
M3 - Conference article
AN - SCOPUS:0035311697
VL - 294
SP - 104
EP - 111
JO - Journal of Nuclear Materials
JF - Journal of Nuclear Materials
SN - 0022-3115
IS - 1-2
ER -