微型堆仪器中子活化分析测定水系沉积物中多个元素

Determination of Multi-Elements in Sediments by INAA with MNSR Reactor

本实验以微型核反应堆为中子源用仪器中子活化分析对水系沉积物中的30个元素常规测定进行了研究。样品在长照射后从第四天开始直到第八天进行每天一次的跟踪测试。研究了有关元素的最佳冷却时间,从而得到了最佳探测限。以GSD-11和GSD-8为标准监控样品,对实验结果的精密度和近似检测限进行了计算。长照测试元素La、Sc、As、Sb、Na、W、Gd和Sm的相对标准偏差小于5％,Th、U、Yb、Ta、Rb、K、Fe小于10％,Ho、Ce、Ga、Lu、Br小于15％,Eu、Cs小于20％。短照测试元素为Mg、Al、Mn、In、Ca、V、Dy和Ti。

A routine method of determination of 30 elements in sediments by INAA was developed. This rapid multi-element analytical method is applicable to the geochemical exploration. Continual measurements were taken once every day during the period from 4th to 8th day after irradiation. The optimum decay time was investigated to get the best detection limits. The relative standard deviations for elements with 9h-irradiation are. La, Sc, As, Sb, Na, W, Gd and Sm<5%; Th, U, Yb, Te, Rb, K and Fe<10%; Ho, Ce, Ga, Lu and Br<15%; Eu and Cs<20%. Mg, Mn, Ca, Dy, Ti, V, In and Al are determination with 2min-irradiation.