A new method for MC-ICPMS measurement of titanium isotopic composition: Identification of correlated isotope anomalies in meteorites
A new method for MC-ICPMS measurement of titanium isotopic composition: Identification of correlated isotope anomalies in meteorites
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DOI：
10.1039/c1ja10181a
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发表时间：
2011-11
影响因子：
3.4
通讯作者：
J. Zhang;N. Dauphas;A. Davis;A. Pourmand
中科院分区：
文献类型：
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作者：
J. Zhang;N. Dauphas;A. Davis;A. Pourmand
提出了一种用于精确测量天然样品中钛同位素的新方案。通过离子交换和萃取色谱分两个阶段分离钛。对Ti标准溶液的测试表明，只要Ca/Ti < 20、V/Ti < 2和Cr/Ti < 0.1的原子比存在，Ca、V和Cr的同量异位素干扰就可以得到充分校正。此外，当Zr/Ti原子比<0.002和Mo/Ti<0.04时，Zr2+和Mo2+对Ti+信号没有影响。与这些修正限相比，纯化后的溶液的相应比率低了几个数量级，表明化学分离技术是有效的。这种新开发的方法已成功应用于地理标准和各种块状陨石。我们的结果与 Trinquier 等人的数据非常一致。 (Science, 2009, 324, 374–376)1并揭示了块状陨石中两种钛核素同位素异常之间的线性相关性。这种相关性反映了在块状陨石形成之前钛同位素异常的载流相的不完全混合。
A new protocol is presented for precise measurements of titanium isotopes in natural samples. Titanium was separated via ion-exchange and extraction chromatography in two stages. Tests on Ti standard solutions show that isobaric interferences from Ca, V, and Cr can be adequately corrected, as long as these elements are present at atomic ratios of Ca/Ti < 20, V/Ti < 2, and Cr/Ti < 0.1. Furthermore, Zr2+ and Mo2+ have no influences on Ti+ signals when atomic ratios of Zr/Ti < 0.002 and Mo/Ti < 0.04. Compared with these correction limits, the purified solutions have corresponding ratios several orders of magnitude lower, indicating that the chemical separation technique is effective. This newly developed method has been successfully applied to geostandards and a wide variety of bulk meteorites. Our results are in good agreement with the data from Trinquier et al. (Science, 2009, 324, 374–376)1 and reveal a linear correlation between isotope anomalies of two Ti nuclides in bulk meteorites. The correlation reflects incomplete mixing of the carrier phases for Ti isotope anomalies before bulk meteorite formation.