用于加速器质谱测量的^(151)Sm实验室参考标准的研制  

Preparation of ^(151)Sm calibration standards for AMS measurement

作　　者：寅新艺[1] 何明[1] 董克君[1] 姜山[1] 张春华[2] 张劲松[2] 郑云[2] 

机构地区：[1]中国原子能科学研究院,北京102413 [2]中国核动力研究设计院,成都610005

出　　处：《核技术》2016年第7期67-71,共5页Nuclear Techniques

基　　金：国家自然科学基金(No.11205250)资助~~

摘　　要：介绍了用于HI-13串列加速器质谱(Accelerator Mass Spectra,AMS)测量的^(151)Sm实验室参考标准的研制。^(151)Sm是长寿命放射性核素,自然界不存在。通过富集稳定同位素150Sm(n,γ)反应合成^(151)Sm,并以热电离同位素质谱仪(Thermal Ionization Mass Spectrometry,TIMS)测得样品中同位素比^(151)Sm/150Sm为3.75×10-3,相对不确定度为0.06%。然后加入稳定的同位素154Sm稀释,制得^(151)Sm/154Sm比值分别为(9.25±0.08)×10-7、(8.87±0.08)×10-8、(8.08±0.08)×10-9的系列参考标准。Background： The long-lived fission product ^151Sm plays an important role in environmental science, life science, nuclear data, etc. It is interesting to establish a high precise and sensitivity measurement method with Accelerator Mass Spectra （AMS） and develop a series of standards of ^151Sm. Purpose： The aim is to develop a series of laboratory reference standards for ^151Sm AMS measurements. Methods： The long-lived radioactive nuclide ^151Sm was produced via neutron capture reaction of ^151Sm by the irradiation of 52.6-mg Sm2O3 （with ^151Sm enriched to 87.34%） in the Heavy Water Research Reactor （HWRR） at China Institute of Atomic Energy （CIAE）. The ^151Sm/^150Sm ratio in the irradiated Sm2O3 sample was measured with Thermal Ionization Mass Spectrometry （TIMS） at the Nuclear Power Institute of China （NPIC）. This standard ^151Sm sample was then diluted with the enriched ^154Sm2O3 （^154Sm is enriched to 98.61%） to obtain three other standards. Results： The ^151Sm/^150Sm ratio in the irradiated Sm2O3 sample is 3.75×10^-3 （the relative standard deviation is 0.06%） measured with TIMS. Three standards with ^151Sm/^154Sm ratios of （9.25±0.08）×10^-7, （8.87±0.08）× 10^-8 and （8.08±0.08）×10^-9, respectively, were prepared for the calibration in AMS measurement of 151Sm. The concentrations of Sm in standard solution （I） and diluent solution were measured using isotopic dilution mass spectrometry. Conclusion： The measurement method of TIMS for isotope ratio of ^151Sm was established. A series of standards was prepared for the calibration in AMS measurement of ^151Sm.

关 键 词：加速器质谱 ^151Sm 参考标准 热电离质谱 

分 类 号：TL92[核科学技术—核燃料循环与材料] O572.21[理学—粒子物理与原子核物理]