Abstract

Matrix effects on the intensity of characteristic L X-rays were investigated for X-ray fluorescence (XRF). Lead was selected to be the analyte and samples were prepared with powders of several elements. In XRF analysis, if the sample analyzed is a composite, the emitted characteristic X-rays of an element can be enhanced or weakened by emission from other elements. The weight fraction of Pb and accompanying element in the matrices prepared as tablets of Pb_CCu_1-C, Pb_CZn_1-C, Pb_CMo_1-C and Pb_CCd_1-C by powder metallurgy using pure powders were varied from 10% to 90% with 10% intervals. The K shell absorption edge of Cu and Zn is just below the characteristic L X-ray energies of Pb. However, Mo and Cd emits K X-rays with energies just above the L shell absorption edge of Pb when stimulated by primary photons. All samples were analyzed by XRF using a Si(Li) detector with good resolution and an Am-241 radioactive source to provide characteristic X-ray spectra. The intensities for $L_{\alpha },$ $L_{\beta },$ and $L_{\gamma }$ X-rays were plotted as a function of the Pb concentration and the results were evaluated to characterize matrix enhancement and absorption upon L-shell X-rays.

摘要

针对 X 射线荧光 (XRF) 研究了基质对特征 L X 射线强度的影响。选择铅作为分析物，并用几种元素的粉末制备样品。在 XRF 分析中，如果分析的样品是复合物，则元素发射的特征 X 射线会因其他元素的发射而增强或减弱。Pb _C Cu _1-C、Pb _C Zn _1-C、Pb _C Mo _1-C和Pb _C Cd _1-C片状基质中Pb和伴随元素的重量分数使用纯粉末的粉末冶金在 10% 到 90% 之间变化，间隔为 10%。Cu 和 Zn 的 K 壳层吸收边刚好低于 Pb 的特征 L X 射线能量。然而，当受到初级光子的刺激时，Mo 和 Cd 会发射 K X 射线，其能量恰好高于 Pb 的 L 壳吸收边。使用具有良好分辨率的 Si(Li) 探测器和 Am-241 放射源通过 XRF 分析所有样品，以提供特征 X 射线光谱。强度为${升}_{\alpha },$ ${升}_{\beta },$ 和 ${升}_{\gamma }$ X 射线被绘制为 Pb 浓度的函数，并评估结果以表征 L 壳 X 射线上的基质增强和吸收。