用于实验室间比对的铀矿地质样品制备及铀含量均匀性检验

为进行核地质分析实验室间比对,采集了南方硬岩和北方砂岩铀矿石样本,按照标准物质制备方法制备了2种铀矿地质样品(编号分别为Albriug-09、Albriug-10),其粒度为小于60μm,铀含量分别为497mg·kg~(-1)和935mg·kg~(-1)。对用于样品均匀性检验的时间分辨紫外脉冲光诱导荧光分析法(TRLIF)进行了分析性能有效性评价。TRLIF测定铀的检出限为0.09mg·kg~(-1),测定范围为0.27~1250mg·kg~(-1);当铀含量范围在4.6~514mg·kg~(-1)之间时,其精密度(RSD%)在9.6%~3.43%之间;当铀含量范围在1.7~514mg·kg~(-1)之间时,其正确度(RE%)在±16.3%~±0.2%之间。应用TRLIF对制备的样品进行了铀含量均匀性测试并采用单因子方差分析法进行了统计检验,其统计量F分别为0.61和0.76,均小于临界值F0.05(9,10)(3.02),表明制备的样品均匀性好,符合实验室间比对测定要求。

Preparation and Uranium Content Homogeneity Test of Uranium Geological Samples for Inter-laboratory Comparison

For inter-laboratory comparison exercise among nuclear geological analysis laboratories,two kind of typical uranium ore samples (numbered Albriug-09,Albriug-10) were prepared using the ores collected from hard rock deposit in South China and sandstone uranium deposits in North China in accordance with the standard material preparation technical specifications.The two samples are less than 60μm in particle size and 497mg · kg-1 and 935mg · kg-1,in uranium content for Albriug-09 and Albriug-10,respectively.The time resolved UV pulse light induced fluorescence analysis (TRLIF) was used to analyze uranium content in the samples to test the sample homogeneity.TRLIF has been validated with performance of detection limit 0.09mg · kg-1,determination range 0.27 ～ 1250mg · kg-1 for uranium content,precision (RSD％) 9.6％-3.43％ when the uranium content in the range of 4.6～514mg ·kg-1,accuracy (RE％) ±16.3％-±0.2％ when the uranium content in the range of 1.7～514mg ·kg-1.The TRLIF was applied to determine uranium contents in the homogeneity test.The statistic of F using the single factor variance method were 0.61 and 0.76 less than the critical value of F0.05(9,10) (3.02).The results indicated that the prepared samples were good in homogeneity,suitable forinter laboratory comparison.