岩石标准物质均匀性的XRF检查法

A Study on Homogeneity Test of Powdered Rock Reference Materails by XRF Method

长期以来岩石标准物质均匀性检查多系采用方差分析F检验作包装单元(使用单元)间的均匀程度一致性检验。这种检验以假定单元内物质分布均匀为前提,而对单元内物质分布是否足够均匀未作实际检验。本文主要探讨用XRF法作标准物质均匀性检查的一些问题。

This paper deals with a method of test for the homogeneity of powdered rock reference materials by means of X-ray fluorescence method.The method is simple, rapid and precise and is able to perform multi-element analysis. A conventi- onal method is used "to detect whether the between-unit (long range) variation is statistically significant compared with the vvithin-unit (short range) variation. An XRF method is designed to detect whether the within-unit (short range) variation is statistically significant compared with the known variation of the measurement method as well. The bias of measurement method is separated from the total variance, and a quantitative measure for the inhomogeneity of a material is obtained.Any drift on the XRF signal can be judged by correlation analysis. A formula for calculating the actual subsample mass of XRF determination is derived.The statistical values of F and t are obtained directly from the output of the XRF instrument by a computerized data processing programme.