铀矿地质样品中天然放射性核素比对分析结果的利用

摘要

Eight uranium geological samples named ALBRIUG-1 ～ ALBRIUG-8 have been prepared using expired archive samples as raw material,through proportioning,grinding,particle size examination and homogeneity testing.Through interlaboratory comparison,it has been determined that the specific activities of gross α,gross β,238U,232 Th,226Ra,210Po and 40K in uranium geology samples prepared by the laboratory using physical and chemical analytical methods.The homogeneity testing by ICP-MS with minimum sample weighing (50 mg) shows that two samples named ALBRIUG-1 and ALBRIUG-8 are in homogeneity,in line with the requirements of reference materials,while the remaining six samples ALBRIUG-2 ～ ALBRIUG-7 are not in homogeneity accordingly.The two samples can be used as quality control samples for analysis of natural radionuclides in uranium geology samples.The radionuclides in the sample ALBRIUG-2 to ALBRIUG-7 are basically in a state of equilibrium,the uranium-radium equilibrium coefficient are from 0.988 to 1.079.They may be used as quality control when using physical analysis with sampling volume larger than 150 g.%以实验室日常分析副样为原料,经过配料、研磨、均匀性检查和多家实验室间比对验证,获得了8个铀矿地质样品(ALBRIUG-1～ALBRIUG-8)中总α、总β、238 U、232Th、226 Ra、210 Po和40K比活度值.采用最小称样量(50 mg)的ICP-MS检查均匀性时,2个铀矿地质样品(ALBRIUG-1和ALBRIUG-8)的均匀性较好,符合标准物质要求,可作为实验室天然放射性核素分析质量控制样品使用;其余6个样品(ALBRIUG-2～ ALBRIUG-7)均匀性未达到标准物质要求,但样品放射性核素基本处于平衡状态,其铀镭平衡系数在0.988～1.079之间,可用于取样量较大(大于150 g)的物理分析质量控制参考.