微分析中电离截面公式与实验的比较

COMPARISON OF IONIZATION CROSS-SECTION FORMULAS WITH EXPERIMENTS IN MICROANALYSIS

利用分析电子显微镜在75—200kV 电压下测量一系列纯元素的M和L线标识X射线强度比I(M)/I(L)。和以前测定的强度比汇集在一起,把所有实验数据与由8个电离截面公式得出的计算值作了比较,比较前对强度比进行约化以消除不确定的参量只留下截面的电压依赖关系。这些公式对I(L)/I(K)可分为四组,对I(M)/I(L)分为三组。只有一组公式(包括Fabre de la Ripelle的公式和Schreiber,Wims的公式)与所有实验数据符合得较好。

Characteristic X-ray intensity ratios of M and L lines I(M)/I(L) from a series of pure elements were measured in the analytical electron microscope at 75-200kV. Compiling the previous measured ratios together, all the data have been compared with the calculated values from eight cross-section formulas after normalization in order to eliminate the uncertain parameters, leaving only the voltage dependence of the cross-section. These formulas can be divided into four groups for I(L)/I(K) or three groups for I(M)/I(L) ratios. Only one group, containing two formulas suggested by Fabre de la Ripelle and Schreiber and Wims, is in good agreement with all the experimental data.