从实验上测定了土壤在可见光谱区的激光诱导击穿光谱(LIBS),对测定的光谱结构进行了分析,并对可观测的谱线进行了归属,得出土壤所含的主要元素和部分微量元素;测定了不同Pb掺杂浓度下土壤中微量元素Pb405.78nm谱线的强度,采用内标法拟合得到了该分析谱线的激光诱导击穿光谱定标曲线,由定标曲线的拟合结果计算得到Pb元素的检测限质量分数为36.7×10^-6。
The laser induced breakdown spectroscopy (LIBS) spectra of the soil are measured in the visible spectral region. The main and some trace elements of the soil sample are obtained by the analysis and assignment of spectral structure and spectral lines respectively. Additionally, the intensities of Pb 405.78 nm spectral line are measured at the different concentration of Pb in soil. The LIBS calibration curve of the analytical spectral line is obtained by internal calibration, and the value of detection limit, 36.7 × 10^-6 , is obtained from the fit of the calibration curve.