现场X射线荧光分析技术

Research Development in in-situ X-ray Fluorescence Analysis Techniques

本文从携带式X射线荧光仪器、现场分析技术和技术应用三方面论述了现场X射线荧光分析技术的进展。从X射线激发源、X射线探测器和电子线路单元等角度,将携带式X射线荧光仪划分为四代,即以放射性同位源为激发源、以NaI(Tl)闪烁计数器为X射线探测器为技术特征的第一代仪器;以放射性同位素源和正比计数器为技术特征的第二代仪器;以放射性同位素、电制冷半导体探测器和以嵌入式微处理器为控制核心的多道脉冲幅度分析器为技术特征的第三代仪器;以低功率微型X射线发生器为激发源、电制冷半导体探测器和全数字化X射线能谱采集器为技术特征的第四代仪器。在现场分析技术方法方面,论述了X射线仪器谱解析技术、基体效应校正技术和现场原位分析中不平度效应、湿度效应、荧光颗粒不均匀效应校正技术进展。介绍了现场X射线荧光分析技术在地质矿产普查、环境污染调查、文物现场鉴定和合金分析等领域的应用进展。指出了目前国产携带式X射线荧光仪处于第三代和第四代仪器水平之间,低功率微型X射线发生器和电制冷半导体探测器还依赖于进口,全数字X射线能谱采集器还有待商品化;现场多元素分析的准确度和方法检出限都有待进一步改善;便携式仪器的应用领域有待拓宽。

The developments of in-situ X-ray Fluorescence （XRF） analysis techniques in the fields of Portable XRF Spectrometer, in-situ analytical methods and its applications are described in this paper. Portable XRF Spectrometer has been divided into four generations, based on the aspects of X-ray excitation sources, X-ray detectors and electrical circuit units. The paper also documents some in-situ analytical methodologies for analyzing X-ray spectra, overcoming the influence of the matrix effect, unevenness effect, moisture effect and heterogeneous effect on in-situ XRF analysis results. Finally, some applications in mineral exploration, environmental investigation, cultural relic discrimination and alloy analysis are introduced. The domestic Portable XRF Spectrometer was between generations 11I and IV. The low power miniature X-ray generator and electric refrigeration semiconductor detector were dependent upon importation from foreign countries. The full digital X-ray energy spectrum collector is not yet available commercially. It is also pointed out that there are some capabilities for improving the accuracy and method detection limit of in-situ analysis. Research fields need be broadened to include the applications of Portable XRF Spectrometer.