工作场所空气中铅测定的便携式X射线荧光光谱法

摘要

Objective To investigate the performance index of portable X-ray fluorescence spectrometer in the determination of lead on filter membrane and to provide data for the determination of lead in workplace air.Methods Irradiated with X-ray,the lead wou ld emit speeifie X-rav fluorescence during the process from the excited state back to the ground state.Rapid determination of lead was completed using fluorescence energy and wave length for qualitative analysis and fluorescence intensity for quantitative measurement.Under set conditions,a series of customized calibration samples were measured to create a standard curve for quantitative analysis of lead on filter membrane.Results The regression equ ation obtained using a portable X-ray fluorescence spectrometer to determine the lead on filter membrane was y=0.004x-0.182 (r2 =0.9999).The linear range was 0.00～10.40 mg/m3,the minimum detectable concentration was 0.53 μg/m3,and the minimum quantifiable concentration was 1.76 μg/m3.The relative standard deviation (RSD) ofwithin-run precision of samples with different concentrations was 0.48％～6.22％,the RSD of between-run precision was 2.51％～5.09％,and the degree of accuracy was in the calibration range of standard samples.Conclusion Portable X-ray fluorescence spectrometry is a simple,rapid,repeatable,and accurate method for the determination of lead on filter membrane.%目的 了解便携式X射线荧光光谱仪测量滤膜铅的性能指标,为其用于测定工作场所空气中的铅含量提供数据依据.方法 通过X射线激发铅元素,激发态铅原子返回基态的过程中,发射特征X射线荧光,以荧光的能量和波长定性,以荧光强度定量,完成对铅元素的快速检测.在设定的仪器条件下,通过测量定制的系列浓度铅标定滤膜,制作标准曲线,完成对滤膜铅的定量分析.结果 便携式X射线荧光光谱仪测定滤膜铅含量,回归方程:y=0.004x-0.182,决定系数为0.999 9,线性范围对应浓度为0.00～10.40 mg/m3,最低检出浓度为0.53 μg/m3,测定下限为1.76 μg/m3,不同浓度样品测量批内精密度相对标准偏差(RSD)为0.48％ ～6.22％,批间精密度RSD为2.51 ％～5.09％,准确度测量结果在标准样品的标定范围内.结论 便携式X射线荧光光谱仪测定滤膜铅样本操作简便,检测快速,结果重现性好,准确度高.