多接收器等离子体质谱（MC-ICP-MS）Pb同位素高精度研究  

High-precision Analysis of Pb Isotope Ratios Using MC-ICP-MS

作　　者：何学贤[1] 朱祥坤[1] 杨淳[1] 唐索寒[1] 

机构地区：[1]国土资源部同位素地质重点实验室北京中国地质科学院地质研究所,北京100037

出　　处：《地球学报》2005年第B09期19-22,共4页Acta Geoscientica Sinica

基　　金：本文由国家自然科学基金重点项目（编号：40331005）和国家自然科学基金面上项目（编号：40473039）资助.

摘　　要：多接收器等离子体质谱是近年发展起来的高精度同位素分析手段之一，通过用等离子体质谱测量Pb国际标准物质NBS981和NBS982，显示出多接收器等离子体质谱分析Pb同位素的优势。利用^205T1／^203T1进行作为内标，可以实现Pb同位素的质量分馏校正，极大地提高了Pb同位素分析的重现性。相比较热电离质谱，该方法精度更高，样品的用量更少，测试时间更短，多接收器等离子体质谱测定Pb同位素技术有良好的应用前景。A method for high-precision measurement of Pb isotopes using MC-ICPMS has been established, with the employment of T1 doping technique. The method includes the calibration of the “true value” of T1 isotopes using NBS982 by assuming the mass fractionation factors of Pb and T1 isotopes are equal, and investigation of the effects of T1 concentration doped in Pb solution. Repeated measurements of NBS981 using the techniques developed have obtained the following values： ^208Pb/^206Pb = 2. 1674 ± 0. 0004, ^207Pb/^206Pb = 0. 91478 ± 0. 00018, ^206Pb/^204Pb = 16.9402 ± 0. 007, ^207Pb/^204Pb = 15. 4966 ± 0. 0030, ^208Pb/^204Pb = 36.7155 ± 0. 015. These results are consistent with those of TIMS method using double or triple spikes.

关 键 词：多接收器等离子体质谱 PB同位素 NBS981 NBS982 等离子体质谱分析 接收器 高精度 同位素分析 热电离质谱 同位素技术 

分 类 号：P313.2[天文地球—固体地球物理学] O657.63[天文地球—地球物理学]