分光光度法测定Gd_2O_3-UO_2烧结芯块O/M的研究

Determination of the Oxygen to Metal Atom Ratio for Sintered Gd_2O_3-UO_2 Pellets by Spectrophotometry

分光光度法测定 Gd_2O_3-UO_2烧结芯块氧与金属原子比(O/M)中,浓磷酸为溶剂,U^(6+)离子和U^(4+)离子的特征波长分别选为310nm 和544nm。U^(6+)离子和 U^(4+)离子浓度分别由其特征波长的吸光度值与标准曲线对比来确定。O/M 计算公式由物质内部电中性原理导出。实验表明,烧结芯块中 Gd_2O_3含量和芯块微观均匀性(固溶体含量)对 O/M 的分光光度测定没有影响,分光光度法测定 Gd_2O_3-UO_2芯块 O/M 具有简便、准确和可重复的特点,其标准偏差为0.003。

A new method,spectrophotometry,to determine the oxigen to metal atom ratio(O/M)of sintered Gd_2O_3-UO_2 pellets has been introduced.Concentated phosphoric acid is used for the preparation of tested solutions as a solvent.The specific wave lengths of U^(6+)and U^(4+)ions are selected at 310nm and 544nm respectively with the absorbances at their specific wavelengths, the U^(6+)and U^(4+)can be obtained by comparing with their standardcurves respectively.The O/M ratio will be calculated by means of the formula drawn from electrical neutrability theory. The Gd_2O_3 content and micro-heterogeneity in sintered Gd_2O_3-UO_2 pellets have no obvious in- fluence on the method.It is considered as a fairly ideal method of determination of the O/M ratio of sintered Gd_2O_3-UO_2 pellets.The standard deviationis not more than ±0.003.