College of Biosystems Engineering and Food Science, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, China.
Key Laboratory of Spectroscopy Sensing, Ministry of Agriculture and Rural Affairs, Hangzhou 310058, China.
Molecules. 2018 Sep 28;23(10):2492. doi: 10.3390/molecules23102492.
Rapid detection of Cd content in soil is beneficial to the prevention of soil heavy metal pollution. In this study, we aimed at exploring the rapid quantitative detection ability of laser- induced breakdown spectroscopy (LIBS) under the conditions of air and Ar for Cd in soil, and finding a fast and accurate method for quantitative detection of heavy metal elements in soil. Spectral intensity of Cd and system performance under air and Ar conditions were analyzed and compared. The univariate model and multivariate models of partial least-squares regression (PLSR) and least-squares support vector machine (LS-SVM) of Cd under the air and Ar conditions were built, and the LS-SVM model under the Ar condition obtained the best performance. In addition, the principle of influence of Ar on LIBS detection was investigated by analyzing the three-dimensional profile of the ablation crater. The overall results indicated that LIBS combined with LS-SVM under the Ar condition could be a useful tool for the accurate quantitative detection of Cd in soil and could provide reference for environmental monitoring.
快速检测土壤中的 Cd 含量有利于预防土壤重金属污染。本研究旨在探索激光诱导击穿光谱（LIBS）在空气和 Ar 条件下对土壤中 Cd 的快速定量检测能力，并寻找一种快速准确的土壤重金属元素定量检测方法。分析和比较了空气和 Ar 条件下 Cd 的光谱强度和系统性能。建立了空气和 Ar 条件下 Cd 的偏最小二乘回归（PLSR）和最小二乘支持向量机（LS-SVM）的单变量模型和多变量模型，Ar 条件下的 LS-SVM 模型获得了最佳性能。此外，通过分析烧蚀坑的三维轮廓，研究了 Ar 对 LIBS 检测的影响原理。总体结果表明，Ar 条件下结合 LS-SVM 的 LIBS 可以成为土壤中 Cd 准确定量检测的有用工具，并可为环境监测提供参考。
