High sensitivity determination of iridium contents in ultra-basic rocks by INAA with coincidence gamma-ray detection

Nuclear Engineering and Technology

Jin Kuwayama¹  Naoki Shirai²  Yosuke Toh³  Mitsuru Ebihara⁴ 

[1] Corresponding author. Department of Earth Sciences, Waseda University, Tokyo, Japan.;Department of Chemistry, Tokyo Metropolitan University, Tokyo, Japan;Department of Chemistry, Tokyo Metropolitan University, Tokyo, Japan;Department of Earth Sciences, Waseda University, Tokyo, Japan;

关键词: Instrumental neutron activation analysis (INAA);    Iridium;    Ultra-basic rocks;    Multiple Ge detector System;    Coincidence counting;    Inductively coupled plasma mass spectrometry (ICP-MS);   

DOI  :  

来源: DOAJ

【 摘 要 】

Very low contents (in the range of 10−9 g/g) of Ir in mantle-derived rock samples (komatiites) were non-destructively determined by INAA coupled with coincidence gamma-ray spectrometry using 16 Ge detectors. Aliquots of the same samples were analyzed by NiS fire-assay ICP-MS for Ir and other platinum group elements. Because the INAA procedure used in this study is non-destructive and is almost free from spectral interference in gamma-ray spectrometry, the INAA values of Ir contents obtained in this study can be highly reliable. Iridium values obtained by ICP-MS were consistent with the INAA values, implying that the ICP-MS values of Ir obtained in this study are equally reliable. Under the present experimental conditions, detection limits were estimated to be 1 pg/g, which corresponds to 0.1 pg for a sample mass of 0.1 g. These levels can be even lowered by an order of magnitude, if necessary, which cannot be achieved by ICP-MS carried out in this study.

【 授权许可】

Unknown