基于热电离质谱的单微粒铀同位素分析方法比较

在核保障中，测定擦拭样品单微粒中铀同位素比可为探测未申报或隐匿的核活动提供重要的信息。裂变径迹 热电离质谱（FT TIMS）是该领域中的主流技术之一，近年来提出了一种新技术——扫描电子显微镜 热电离质谱（SEM TIMS）。本文通过对标准微粒样品的测定系统评估比较了该两种方法。该两种方法的测量结果均与标准微粒的参考值吻合较好，FT TIMS易于寻找、定位易裂变核素，对高浓铀具有极高的灵敏度。SEM TIMS则更易于同步开展含铀微粒形貌学和元素组成等分析，可视作FT TIMS有益的补充。

Comparative Study on Uranium Isotopic Analysis for Single Particle Based on Thermal Ionization Mass Spectrometry

In nuclear safeguards, measurement of uranium isotope ratio in single particle from swipe samples provides crucial information for detecting undeclared or clandestine activities. Fission track analysis combined with thermal ionization mass spectrometry (FT TIMS) is one of the dominant techniques in this field. With the development of technique, a new approach, scanning electron microscopy combined with thermal ionization mass spectrometry (SEM TIMS) was introduced in recent years. Both methods were evaluated by testing the same uranium standard particles in the paper. The result shows a good agreement with certified values. FT TIMS is prone to identify and locate fissile nuclides and has a high sensitivity for highly enriched uranium (HEU). SEM TIMS which is compatible with morphological and elemental analysis could be considered as a beneficial supplement for FT TIMS.