土壤样品Ge(Li)反康普顿γ谱的分析

Soil sample analyses with anti-Compton Ge(Li) gamma-ray spectrometry

本文报告了用高灵敏度高分辨率Ge(Li)反康普顿γ谱仪分析土壤样品的几种方法。通过用含量已知的实配标准样进行检验;同时用美国国家标准局提供的标准样作传递而制定的标准土壤样品进行比对;并与国内若干实验室对土壤样品分析的结果比较。结果表明:用Ge(Li)反康普顿γ谱比单一Ge(Li)谱确定土壤样品中放射性核素,尤其是^(238)U,方法更简便、准确度更高。用^(182)Ta+^(152)Eu加土壤标准源刻度确定的效率曲线,对反康谱分析结果的准确度最高,优于±3％。

This paper reports on several methods of analyzing soil samples by using an anti-Compton Ge(Li) gamma-ray spectrometer with high sensitivity and resolution. The methods have been examined with the standard samples having known composition and the standard soil samples transferred by NBS standard. The results were also compared with those from other laboratories. It was shown that for the determination of radionuclides, especially 238U, in soil samples, the use of anti-Compton Ge(Li) spectrometry is a handier way with a higher accuracy than the method using Ge(Li) spectrometry merely. When analyzing an anti-Compton spectrum using the efficiency curve measured with a 132Ta + 152Eu + soil standard source, the accuracy of results is the highest (better than