快中子诱发裂变测定铀同位素丰度

铀同位素丰度分析是核燃料循环中重要的分析项目。本工作在中子活化基础上提出用T(d,n)⁴He反应产生的快中子诱发裂变铀样品来测定铀同位素丰度的分析方法。该方法利用铀同位素丰度与特定裂变产物的平均产额比呈指数关系的特点，选择〖AKY-〗(⁹²Sr)/〖AKY-〗(¹⁰⁵Ru)、〖AKY-〗(⁹²Sr)/〖AKY-〗(¹³⁵I)与铀同位素丰度间的关系曲线作为工作曲线，并对模拟样品进行分析。结果表明，〖AKY-〗(⁹²Sr)/〖AKY-〗(¹⁰⁵Ru)、〖AKY-〗(⁹²Sr)/〖AKY-〗(¹³⁵I)计算结果与模拟样品的相对偏差分别为0.8%和1.8%，RSD优于3%，与γ能谱法的分析结果相符合。

Determination of Uranium Isotope Abundance by Fast Neutron-Induced Fission

The determination of uranium isotope abundance is the important analysis item in nuclear fuel cycle. Based on neutron activation analysis, a new method was presented for determination of uranium isotope abundance by fission induced by fast neutron generated by T(d, n)⁴He. The exponential relation between different abundances of ²³⁵U and the averaged fission yields ratio of special fission production was used in this method. Through a series of experiments, the working curve selected the relationships between abundances and the ratios of fission yields (〖AKY-〗(⁹²Sr)/〖AKY-〗(¹⁰⁵Ru), 〖AKY-〗(⁹²Sr)/〖AKY-〗(¹³⁵I)). The simulation samples were measured. The relative deviations are 0.8% and 1.8% respectively, RSD is excelled 3%, and the result is coincident with that of γ spectrometry method.