通过测量模拟样品中^(236)U与^(238)U原子个数比估算燃耗的探索研究

Primary Study on Burnup Estimation of Irradiated Uranium by Determining Ratio of ^(236)U and ^(238)U Atom Number in Simulated Samples

自然界中236 U与238 U原子个数比约10-14,不同反应堆类型及核燃料辐照情况辐照后的核材料中236 U与238 U原子个数比不同,一般为天然236 U与238 U原子个数比的107~1011倍。通过测量环境样品中的236 U与238 U原子个数比可探知取样点附近进行过的辐照活动、环境污染的来源及对应核燃料的燃耗。本研究使用配制的模拟样品,建立了多接收电感耦合等离子质谱(MC-ICP-MS)技术测定236 U与238 U原子个数比的方法以及估算核燃料燃耗的工作方案,并与其他燃耗计算方法比较,燃耗的相对偏差约10%。

The ratio of 236 U and 238 U atom number is different depending on the type of reactor and the status of irradiation of nuclear materials ,w hich is usual 107-1011 times than that in nature .The irradiation activity near sampling spots ,the source of irradia-tion contamination ,and the burnup of spent nuclear fuel can be explored by measuring ratio of 236 U and 238 U atom number in environmental samples .T he method of measuring ratio of 236 U and 238 U atom number in simulated samples by MC-ICP-MS and the working schedule for estimating burnup of spent nuclear fuel have been established . Compared with the other methods ,the relative deviation of burnup is about 10% .