The structure of triuranuim octaoxide ( u3o8 ) and the oxidation of uranium metal were studied by x - ray diffraction ( xrd ) and rietveld method in different partial pressure of oxygen and temperatures 本论文利用x射线衍射( xrd )并结合rietveld方法较系统地对金属铀和八氧化三铀( u _ 3o _ 8 )在不同温度、压力条件下的表层氧化情况和结构变化进行了分析研究。