含铅污泥中Pb的激光诱导击穿光谱定量反演研究

Quantitative retrieval research of Pb in lead slime by laser induced breakdown spectroscopy

为了实现含铅污泥中Pb的快速定量反演分析,选取PbⅠ:405.78nm为分析线,从谱线强度、信背比以及信号的相对标准偏差三方面研究了激光能量对含铅污泥中铅的激光诱导击穿光谱特性的影响。在23.1m J^135.4m J范围内,谱线强度随激光能量线性增加,信背比先增加后降低最终趋于稳定,信号的相对标准偏差随着激光能量的增加先减小后趋于稳定。配制了不同质量分数含铅污泥的样品,获得了铅的定标曲线。结果表明,在质量分数为0.001118~0.020115范围内,谱线强度与Pb含量之间有较好的线性关系,相关系数达到0.991;在此方法下,得到含铅污泥的Pb含量测量值与实际值之间的相对误差为8.72%。此方法能够实现含铅污泥中Pb的快速定量反演检测。

In order to achieve fast quantitative retrieval analysis of Pb in lead slime,PbⅠ：405. 78 nm was selected as the analytical line. The influences of laser energy on the laser induced breakdown spectroscopy characteristics of Pb in lead slime were discussed from three areas of spectral intensity,the ratio of signal and background and the relative standard deviation of signal. Within the range of 23. 1mJ - 135. 4mJ,line intensity increases linearly with the increase of laser energy,the ratio of signal and background increases at first and then decreases,and eventually stabilizes. The relative standard deviation of the signal decreases at first and then stabilizes with the increase of laser energy. The samples of lead slime with different mass fractions were prepared and the calibration curve of Pb was obtained. The results show that within the range of mass fraction of 0. 001118 - 0. 20115,spectrum intensity has the good linear relationship with Pb content. The correlation coefficient reaches 0. 991. With this method,the relative error between measurement value and real value of Pb content of lead slime is 8. 72%. This method can provide fast and quantitative retrieval measurement of Pb in lead slime.