Precise measurement of stable neodymium isotopes of geological materials by using MC-ICP-MS
Precise measurement of stable neodymium isotopes of geological materials by using MC-ICP-MS
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DOI：
10.1039/c3ja50229e
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发表时间：
2013-11
影响因子：
3.4
通讯作者：
Jinlong Ma;G. Wei;Ying Liu;Zhong‐Yuan Ren;Yigang Xu;Yonghong Yang
中科院分区：
文献类型：
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作者：
Jinlong Ma;G. Wei;Ying Liu;Zhong‐Yuan Ren;Yigang Xu;Yonghong Yang
建立了一种多接收电感耦合等离子体质谱（MC-ICP-MS）样品标准交叉进样（SSB）高精度测定地质样品中Nd稳定同位素组成的方法。Nd通过双柱离子交换色谱程序进行预浓缩和纯化。Nd的回收率一般优于96%，并且可以有效地去除诸如Ce和Sm的干扰，使得在质谱测量期间对Nd稳定同位素组成的影响可以忽略。根据Nd标准溶液的长期测量结果，e142 Nd、e145 Nd、e146 Nd和e148 Nd的稳定同位素组成的内部精密度一般优于± 0.2（2SEM），外部精密度e142 Nd、e145 Nd和e146 Nd一般优于±0.2（1 SD），e148 Nd一般优于±0.5（1 SD）。例如拉霍亚、Nd-GIG和NIST 3135 a。内、外精密度均与双加标法相当。我们对拉霍亚的e142 Nd、e145 Nd、e146 Nd和e148 Nd的测量结果的平均值与双加标法测量结果的平均值在分析误差范围内是一致的。因此，我们的方法可以提供与双尖峰方法相当的结果，而不会带来任何不便的校准双尖峰，效率大大提高。这为研究地质作用中的Nd稳定同位素提供了一种更为方便的途径。用该方法测定了一系列国际岩石标准样品的Nd稳定同位素组成。
A method has been developed to determine high-precision stable Nd isotopic compositions in geological samples by multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) using sample-standard-bracketing (SSB) mode. Nd was pre-concentrated and purified through a two-column ion-exchange chromatographic procedure. The recovery for Nd is generally better than 96%, and the interferences, such as Ce and Sm can be efficiently removed, allowing negligible influence on the stable Nd isotopic composition during mass spectrometry measurement. The internal precision for the stable Nd isotopic compositions, e142Nd, e145Nd, e146Nd and e148Nd were generally better than ±0.2 (2 SEM), and the external precision was generally better than ±0.2 (1 SD) for e142Nd, e145Nd and e146Nd, and better than ±0.5 (1 SD) for e148Nd based on the long-term results of the Nd standard solutions, such as La Jolla, Nd-GIG and NIST 3135a. Both the internal and external precisions are comparable to those by double-spike method. The averages of our measured e142Nd, e145Nd, e146Nd and e148Nd results of La Jolla are identical to those by the double-spike method within analytical error. Thus, our method can provide comparable results with the double-spike method, but does not bring any inconvenience of calibrating double spikes, and the efficiency is greatly improved. This provides a more convenient way for studying stable Nd isotopes in geological processes. By using this method, the stable Nd isotopic compositions for a series of international rock standard references were measured.