热力学模型的氧化Ln化UO2的氧化
V L Vinograd1, A A Bukaemskiy2, G Deissmann2
1Institute of Energy and Climate Research-Nuclear Waste Management (IEK-6), Forschungszentrum Jülich GmbH, Jülich, Germany. v.vinograd@fz-juelich.de.
Scientific reports
|October 20, 2023
概括
与兰化物合的二氧化 (UO2) 相比,与纯UO2相比,具有更强的氧化阻力. 废核燃料中这种改善的稳定性归因于氧化过程中化物分离.
科学领域:
- 核材料科学是核材料的科学.
- 固态化学 固态化学
- 热力学是一种热力学.
背景情况:
- 用兰化物添加的UO2作为使用过的核燃料 (SNF) 的模型.
- 了解SNF的抗氧化能力对于核废物管理至关重要.
- 裂变产物显著影响SNF的化学稳定性.
研究的目的:
- 为了研究丁化物合的UO2的氧化行为.
- 为了比较UO2-UO3和LnO1.5-UO2-UO3系统的热力学.
- 阐明Ln-化UO2.2增强氧化电阻背后的机制.
主要方法:
- 一个热力学模型的开发.
- 模型的应用来分析氧化过程中的相变.
- 从化物到U3O8.8的氧化过程的研究.
主要成果:
- 开发了一种热力学模型,并应用于Ln-doped UO2氧化.
- 研究了从化物到U3O8氧化过程中的详细相变.
- 化物和U3O8相之间的兰化物分离被确定为一个关键因素.
结论:
- 与纯的UO2相比,与兰化物合的UO2具有较高的氧化电阻.
- 这种增强的稳定性可能是由于热力学驱动的兰坦化物分离.
- 在环境温度下缓慢扩散会阻碍这种分隔,从而有助于稳定性.
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