双气流路-激光剥蚀电感耦合等离子体质谱测定铅同位素比值  

Determination of Lead Isotope Ratio by Dual Gas Flow-Laser Ablation-Inductively Coupled Plasma-Mass Spectroemtry

作　　者：靳兰兰[1] 姜劲峰[2] 胡圣虹[1] 张宏飞[1] 

机构地区：[1]中国地质大学地球科学学院地质过程与矿产资源国家重点实验室,武汉430074 [2]中国地质大学材料科学与化学工程学院,武汉430074

出　　处：《分析化学》2007年第2期191-195,共5页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金(No.20575061);湖北省自然科学基金(2006ABA351)资助项目

摘　　要：采用双气流路校正-激光剥蚀电感耦合等离子体质谱测定了地质样品中Pb同位素比值,并通过201Hg和指数法则分别校正分析过程中的同量异位素干扰和质量偏移。实验结果表明,采用双气流校正系统可明显提高Pb信号强度,且当干、湿气溶胶流速比为1时铅的信号强度最大。将该方法用于地质标准物质NIST610和BCR-2G测定,分析结果与参考值符合,相对标准偏差RSD在1%以内(n=8)。A method for the determination of lead isotope ratio in geological sample with dual gas flow calibration-laser ablation inductively coupled plasma mass spectrometry （LA-ICP-MS） was described. 201Hg and the exponent principle were used to calibrate the isobaric interference and mass discrimination in LA-ICP-MS analysis, respectively. The results showed that the intensities of analytical signal for Pb were extremely improved with dual gas flow system. The optimum signal intensities and precision of isotope ratio were obtained when the ratio of the flows between dry aerosols and wet aerosols was about 1. The proposed method was applied to analysis of geological standard reference materials such as NIST610 and BCR-2G, and the analytical results were in good agreement with the reference values, with RSD ≤ 1% （ n = 8 ）.

关 键 词：双气流路 激光剥蚀电感耦合等离子体质谱 铅同位素比 

分 类 号：O657.63[理学—分析化学]