邻近铀微粒的二次离子质谱测量干扰研究  

Study on the Interferences of Adjacent Uranium Particles to Particle Anlysis by Secondary Ion Mass Spectrometry

作　　者：张燕[1] 赵永刚[1] 王同兴[1] 沈彦[1] 王凡[1] 鹿捷 ZHANG Yan;ZHAO Yong-gang;WANG Tong-xing;SHEN Yan;WANG Fan;LU Jie(China Institute of Atomic Energy,Beijing 102413,China)

机构地区：[1]中国原子能科学研究院,北京102413

出　　处：《质谱学报》2021年第3期326-333,I0005,共9页Journal of Chinese Mass Spectrometry Society

摘　　要：二次离子质谱(SIMS)测定铀微粒同位素比时,邻近微粒间可能产生干扰。在IMS-6f型SIMS上开展U350和U0002铀微粒在不同间距、不同测量顺序下铀同位素比测量研究,结果表明,微粒间距超过22μm(U350)和35μm(U0002)时,微粒的^(234)U/^(238)U、^(235)U/^(238)U、^(236)U/^(238)U测定结果与标称值相符;相同间距时,丰度低的微粒比丰度高的微粒受到的干扰严重,安全距离也更大;同一距离下,后测量的微粒比先测量的微粒受到的干扰严重,形貌疏松、尺寸小的微粒比密实、尺寸大的微粒受到的干扰严重。由已知两种丰度微粒计算得出的线性组合系数K_(4)(^(234)U/^(238)U)、K_(5)(^(235)U/^(238)U)和K_(6)(^(236)U/^(238)U)是否相近可以作为可疑混合微粒的判断准则。采用微操作进行单微粒剥离是消除相邻微粒干扰的有效方法。该工作为SIMS分析过程中有邻近微粒干扰时,发现、处理和排除可疑混合微粒数据,准确测量铀微粒同位素提供了参考。There may be mutual interference between adjacent particles on uranium particle isotope ratios analysis by secondary ion mass spectrometer(SIMS).The influences of distance and measurement order were investigated for U350 and U0002 uranium isotope ratios analysis with IMS-6f SIMS.When the distance was over 22μm for U350 and 35μm for U0002 under the conditions of this study,the measured results of ^(234)U/^(238)U,^(235)U/^(238)U and ^(236)U/^(238)U of particles were in good agreement with the certified value.The poorer particles would be interfered severer than the richer ones under the same distance,and the safe distance is more farther for the poorer particles.The later measured particles would be interfered severer than the former ones when particles were analyzed one by one.The smaller,loser and thinner particles would be interfered severer than the larger and denser ones.Whether the linear combination coefficients of K_(4)(^(234)U/^(238)U)、K_(5)(^(235)U/^(238)U)and K_(6)(^(236)U/^(238)U)values were equal,and could be used to identify“mixed particles”,particle isolation with micro-manipulation was effective for eliminating neighboring particles interference.These results will provide references to adjacent uranium particles analysis by SIMS,so as to discover,handle and eliminate the suspected mixed particle data.

关 键 词：二次离子质谱(SIMS) 微粒分析 微操作 核保障 

分 类 号：O657.63[理学—分析化学]