激光诱导等离子体的物理特性研究及其对定量分析结果的影响

项目名称： 激光诱导等离子体的物理特性研究及其对定量分析结果的影响

项目编号： No.11504091

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 数理科学和化学

项目作者： 王静鸽

作者单位： 河南科技大学

项目金额： 21万元

中文摘要： 激光诱导击穿光谱(LIBS)作为一种新型的物质成分分析方法已经被应用于越来越多的领域。激光诱导等离子体是该技术的物理基础，它的特性与实验系统的诸多参数密切相关。目前由于对等离子体光谱特性的研究还不够完善，使LIBS的光谱信号稳定性以及检测精度受到限制。本项目以提高LIBS的分析性能为目标，分别以合金钢和炉渣为样品，采用等离子体图像与光谱信号相结合的方法探索等离子体产生和演变的物理机制，分析谱线辐射强度、等离子体温度、电子密度、粒子密度等参数在空间不同区域的分布特征；研究Abel逆变换数值算法反演等离子体由内到外的辐射特性，建立等离子体在三维空间内的光谱分布模型，通过对光谱自吸收校正算法的研究对模型进行修正；然后，以此模型为基础选取等离子体中具有较稳定光谱信号的区域对样品成分进行定量分析。本项目的开展将为提高LIBS技术的检测精度提供理论指导和实验依据，进而促进LIBS技术的实用化和商品化。

中文关键词： 激光诱导等离子体；三维空间分布；自吸收校正；定量分析

英文摘要： As a new method for composition analysis, Laser-induced breakdown spectroscopy (LIBS) has been applied to more and more fields. The physical basis of LIBS is laser-induced plasma, the characteristics of which are closely related to many experimental parameters of the system. At present, because the study of plasma characteristics is still not perfect, the signal stability and detection accuracy of LIBS are limited. In this project, in order to improve the analysis performance of LIBS, the steel and slag are selected as the sample. Plasma images and spectral signals are combined to explore the physical mechanism of the process of plasma generation and evolution. The distribution characteristics of spectral radiation intensity, the plasma temperature, electron density, particle density are analyzed. The numerical algorithms of Abel inversion is studied to inverse the plasma radiation characteristics from the inside to the outside. The spectral distribution model of the plasma in three-dimensional space would be established. Then the spectral self-absorption correction algorithms are investigated to correct the plasma model. Finally, the best regions in the plasma with stable spectral signals were selected for quantitative analysis. This project will provide theoretical guidance and experimental basis to improve the detection accuracy of LIBS. It will further promote the practical and commercialization of LIBS.

英文关键词： Laser-induced plasma;Three-dimensional spatial distribution;Self-absorption correction;Quantitative analysis