【摘要】 以光谱分析法为原理,采用新型的硅漂移探测器和高性能的低功率X射线管搭建了一台便携式能量色散X射线荧光光谱仪检测系统,为使X射线管的激发有效增强和探测器的工作效率提高,重新整合了硬件平台,优化了光路系统的几何布局;简单介绍了光谱仪的工作原理和上、下位机的结构组成以及光谱数据的采集,着重介绍了光谱数据的形式和上位机数据预处理过程以及镉大米的定性定量方法;结果表明,设计的检测系统寻峰的绝对误差在3%以内,定量的相对误差可控制在10%以内,样品测量的平均时间为900s;上位机分析软件是基于.NET Framework平台用C#语言结合MATLAB语言进行的混合编程,定量分析的检出限为0.051 5ppm,定量限为0.171 6ppm;精度和稳定性满足要求,具有误差小、操作简单、方便快速、安全稳定等特点,为现场原位检测镉大米提供了另一种方法。更多还原

【Abstract】 Based on the principle of spectral analysis,aportable energy dispersive X-ray fluorescence spectrometer detection system was built by using a new type of silicon drift detector and high performance low power X-ray tube.In order to effectively enhance the excitation of the X-ray tube and work efficiency of the detector,re-integration of the hardware platform to optimize the geometric layout of the optical system.The working principle of the spectrometer and the structure of the upper and lower machines and the acquisition of the spectral data are introduced simply.The form of the spectral data and the data pretreatment process of the upper machine and the qualitative and quantitative methods of the cadmium rice are introduced emphatically.The results show that the peaks finding absolute error of the designed detection system is less than 3%,the quantitative relative error can be controlled within 10% and the average time of the sample measurement is 900 s.The upper machine analysis software is based on the.NET Framework platform with C#language combined with MATLAB language for mixed programming.The detection limit is 0.0515 ppm,and the limit of quantitation is 0.1716 ppm.The precision and stability of the system meet the requirements,with small error,simple operation,fast,convenient,safe and other characteristics,which provides another new method for the in-situ detection of cadmium rice.更多还原