碱金属元素对稀土激光微等离子体基体效应研究

The study of matrix effect of alkali metal elements on the laser micro-plasma of rare-earth

本文以激光微区光谱分析仪结合CCD光栅光谱仪为分析系统,在减压氩气环境下,以EuⅡ420.505 nm、SmⅡ443.434 nm、DyⅡ400.048 nm、TmⅡ424.215 nm为分析线,研究了碱金属元素锂、钠、钾对稀土激光微等离子体的基体效应.结果表明:掺有碱金属元素的基体与空白基体相比,谱线强度都有明显的增强,其中钾元素的增强程度最大,得出钾元素是一种很好的光谱载体;掺有碱金属元素的基体所对应的电子温度和电子密度与空白基体相比有明显的下降,认为分析谱线增强的主要机理为,碱金属元素的掺入降低了等离子体的电子温度,使其向谱线的标准温度靠近所致.

Laser micro-spectral analyzer, coupled with CCD spectrometer, was used to study the matrix effect which matrixes elements are Li, Na and K on the laser micro-plasma of rare-earth in argon atmosphere at reduced pressure, with EuⅡ420.505nm、SmⅡ443.434nm、DyⅡ400.048nm、TmⅡ424.215nm as analysis spectral lines. It is founded that comparing with that in matrix which has no alkali metal elements, the intensity of spectral lines have an obvious increase, especially that in K matrix, which suggests K element is a perfect spectroscopic carrier. Both electronic temperature and electronic density are lower than that in the matrix of no alkali metal elements and the reason of enhancement of spectral lines intensity is explained.