液闪法测定^(151)Sm的半衰期  

The measurement of the half-life of ^(151)Sm by liquid scintillation counter

作　　者：石国柱[1,2] 何明[2] 王祥高[2] 李朝历[2] 王伟[2] 黄春堂[1,2] 张大伟[1,2] 吴绍雷[2] 沈洪涛[2] 吕晓霞[2] 武绍勇[2] 吴伟明[1] 姜山[2] 

机构地区：[1]广西大学物理科学与工程技术学院,南宁530004 [2]中国原子能科学研究院核物理所,北京102413

出　　处：《核技术》2009年第7期537-540,共4页Nuclear Techniques

摘　　要：采用液闪β放射性计数法(LSC)测量中国原子能科学研究院重水堆上辐照后样品中151Sm的活度,用表面热电离质谱(TIMS)和电感耦合等离子质谱仪(ICP-AES)法结合测得样品中151Sm的原子个数,计算得到151Sm半衰期。在LSC实验测量前的γ谱和β谱测量表明,干扰核素152Eu、154Eu、40K等对151Sm的LSC测量影响可忽略。用14C的效率示踪-液闪法测定151Sm的比活度为(603.3±15.1)Bq/mg,相对误差为2.5%,原子个数测量结果为2.769×1012个,求得151Sm半衰期为(96.7±2.8)a,相对误差为2.9%。A method to determine ^151Sm activity by liquid scintillation counter （LSC） was described and the ^151Sm half-life was obtained in this paper. The T and 13 spectra of neutron-activated ^151Sm samples revealed that effects of the interfering nuclides on the ^151Sm LSC measurement were negligible. Activity of the ^151Sm samples was determined by LSC through the efficiency tracing （ET）. A ^151Sm sample of specific activity of （603.3±15.1） Bq/mg was obtained in the original sample and its relative standard error was 2.5%. ^151Sm/^151Sm ratio of （3.750±1.002）×10^-3 was obtained in the original sample by TIMS and ICP-AES with the XSISm sample of specific activity. Finally, the half-life of ^151Sm of （96.7±2.8）a was obtained, with a relative standard error of 2.9%, which is more accurate than other measurements.

关 键 词：151Sm 液闪β放射性计数法 效率示踪 表面热电离质谱 

分 类 号：O571.1[理学—粒子物理与原子核物理]