The oxygen self-diffusion coefficients in near stoichiometric (U,Pu)O₂ at high temperatures were successfully measured by thermogravimetry combined with the oxygen isotope exchange method. The activation energy for oxygen diffusion in the stoichiometric composition of (U,Pu)O₂ was evaluated from experimental data, and the value was determined to be 248 kJ/mol. In addition, the defect migration energies of (U,Pu)O_2±x were derived, and the oxygen self-diffusion coefficients were evaluated using these. As a result, good agreement was found between the experimental data and the oxygen self-diffusion coefficients calculated using the defect migration energies.

中文翻译：

---

1673-1873 K高温下近化学计量（U，Pu）O ₂中的氧自扩散

通过热重分析法结合氧同位素交换法成功地测量了高温下近化学计量（U，Pu）O ₂的氧自扩散系数。从实验数据评估（U，Pu）O ₂的化学计量组成中用于氧扩散的活化能，该值确定为248kJ / mol。另外，导出（U，Pu）O _2±x的缺陷迁移能，并使用它们评估氧的自扩散系数。结果，在实验数据和使用缺陷迁移能计算出的氧自扩散系数之间找到了很好的一致性。