铀同位素丰度的精确测定

A Precise and Accurate Determination for Uranium Isotope Abundance

摘要: 本报告介绍用MAT-260型质谱计测定铀同位素丰度,着重探讨了影响数据精确度的因素,并采用美国国家标准局(NBS)样品对测得的数据进行校正,以保证其较高的准确度。在此基础上对天然铀,堆后料和~(235)U丰度为50％左右的样品进行了多次测定,结果表明:R_(58)(~(235)U对~(238)U的丰度比)值的测定精密度优于±0.06％,准确度为±0.2％。

Abstract: Some problems of determining uranium isotope abundance by MAT-260 mass tpectrometer, especially, the influence factors on precision and accuracy are di-acussed. NBS standard samples are used for calibrating the acquisited data. Onthis base, natural uranium, uranium of isotope abundancc 50% as well as deple-ted materials are determined for many times. Measured precision of R_(58) (abun-dance ratio of ~(235)U to ~(238)U) is better than ±0.06%, accuracy within ±0.2%.

1． GARNER, E. L, et alii "Sta