Signal-to-noise ratios in forensic glass analysis by micro X-ray fluorescence spectrometry
Signal-to-noise ratios in forensic glass analysis by micro X-ray fluorescence spectrometry
复制标题
DOI：
10.1002/xrs.2437
复制
发表时间：
2014-01-01
影响因子：
1.2
通讯作者：
Almirall, J. R.
中科院分区：
文献类型：
--
作者：
Ernst, T.;Berman, T.;Almirall, J. R.
使用能量色散X射线（EDS）检测器的微X射线荧光（-XRF）光谱法能够检测某些主要、次要和痕量元素，这些元素允许在法医案件中基于元素组成的差异对玻璃碎片进行潜在区分。通常，用于区分的元素的浓度接近EDS系统的检测限，并且是否在比较分析中利用这些次要峰的决定通常由检查员自行决定。使用光谱峰的信噪比（SNR）提供了额外的客观性，在峰识别/标签的决定，并在半定量比比较的元素的选择。此外，SNR的使用使得能够计算检测限和定量限以及监测仪器性能，并且促进不同XRF配置的性能比较。本文演示了一种实用的方法，应用的SNR，检测限和定量限的概念，XRF产生的EDS光谱，讨论了这种测定的影响，解决了光谱特性，必须考虑的计算时，并说明了应用这些概念的例子法医检查和比较的玻璃样品。版权所有（c）2012约翰威利父子有限公司
Micro X-ray fluorescence (-XRF) spectrometry using an energy dispersive X-ray (EDS) detector is capable of detecting certain major, minor, and trace elements that permit potential discrimination of glass fragments in forensic cases on the basis of differences in elemental composition. Often, elements used for discrimination are present at concentrations near the detection limit of the EDS system, and the decision whether to utilize these minor peaks in a comparative analysis has generally been left to the discretion of the examiner. The use of signal-to-noise ratios (SNRs) of spectral peaks provides additional objectivity in peak identification/label decisions and in the selection of elements in semiquantitative ratio comparisons. In addition, the use of SNRs enables calculations of limits of detection and limits of quantitation and the monitoring of instrument performance, and facilitates performance comparisons of different -XRF configurations. This paper demonstrates a practical method for applying the concepts of SNR, limits of detection, and limits of quantitation to -XRF generated EDS-based spectra, discusses the implications of such determinations, addresses spectral features that must be considered when making the calculations, and illustrates the application of these concepts to the example of forensic examination and comparison of glass samples. Copyright (c) 2012 John Wiley & Sons, Ltd.