RPQ-IC检测系统测量低丰度铀同位素

Determination of Low Abundance Uranium Isotope by RPQ-IC Collector System

介绍了采用 Finnigan MAT 2 62热电离质谱计检测 NBS U 0 1 0、浓缩 2 3 3 U硝酸溶液 ( IRMM-0 40 a)。采用阻滞电位四极杆 ( RPQ) -IC装置测量低丰度铀 2 3 4 U、2 3 5U、2 3 6U的同位素丰度比 ,并与 Faraday(法拉第杯 )检测的数据进行比较。采用偏转法对 RPQ产额进行了校正。实验表明 :所得结果在误差范围内 ,RPQ-IC测量结果比 RPQ-FAR测量结果偏高 0 .1 4% ;RPQ-IC测量低丰度铀同位素的内精度比法拉第杯测量结果高 ,外精度比 FAR杯测量结果也高 ;RPQ产额变化比较大 ,但只要注意产额校正 。

The samples including NBS U010, concentrated nitric acid solution of 233U(IRMM-040a)were determined by Finnigan MAT 262 thermal ionization mass spectrometry. The isotopic ratios in low abundance uranium included 234U, 235U, 236U were determined by RPQ-IC collector system. The results were compared with data obtained from Faraday cup. The calibration of RPQ yields by deflexion was described. The result shows that the determination datun is in the range of error, the result obtained from RPQ-IC is 0.14% higher than that from Faraday cup, the inner precision and outer precision from the determination of isotopic ratios of low abundance uranium by RPQ-IC collector system are higher than from Faraday cup. The change of RPQ yields is very significant.