新一代高精度高灵敏度的表面热电离质谱仪(Triton TI)的Nd同位素测定

High Precision Nd Isotope Measurement by Triton TI Mass Spectrometry

利用在南京大学成矿作用研究国家重点实验室建立的新一代高精度高灵敏度的表面热电离质谱仪 (TritonTI) ,可以实现比以往更高精度的Nd同位素测定。 3个国际溶液标样的反复测定结果NdLaJolla :14 3 Nd/ 14 4 Nd为 0 .5 1184 2± 4 ;NdJN di 1:14 3 Nd/ 14 4 Nd为 0 .5 12 10 4± 6 ;NdJMC :14 3 Nd/ 14 4 Nd为 0 .5 115 87± 10。 1个国际岩石标样的测试结果BCR 2 :14 3 Nd/ 14 4 Nd为 0 5 12 6 2 4± 3。上述测试结果与国际上很多实验室的测试结果一致 ,但测试精度优于以往。综合分析表明 ,利用这一最新型号的表面热电离质谱仪 (TritonTI) ,可以实现高精度的Nd同位素组成测试 ,测试精度一般优于 5× 10 -6。

High precision Nd isotope measurement can be achieved by using the new generation of thermal ionization mass spectrometry (Triton TI) operated recently in the State Key laboratory for Mineral Deposits Research,Nanjing University.The authors measured three international Nd solution standards,and the 143 Nd/ 144 Nd ratios are as follows: Nd La Jolla=0.511842±4; Nd JNdi- 1= 0.512104±6;Nd JMC=0.511587±10. The 143 Nd/ 144 Nd ratio for one international rock standard (BCR-2) is 0.512628±3. These values are in excellent agreement with those reported previous by many other laboratories and,what is more,show a much better analytical precision,which the error generally lower than 5 ×10 -6 .