基于飞秒激光等离子体丝诱导击穿光谱探测土壤重金属Cr元素含量

本文基于飞秒激光等离子体丝诱导击穿光谱对土壤重金属Cr元素含量进行了实验研究.利用荧光法对等离子体丝的长度进行测量,给出了在不同焦距聚焦透镜作用下土壤中Cr425.5 nm的谱线强度空间分布,实验给出了Cr元素的定标曲线.实验结果表明,土壤中Cr元素浓度分析测量的相对标准偏差小于5%,土壤中重金属Cr元素的检测极限为7.85 ppm.表明飞秒激光等离子体丝诱导击穿光谱技术在土壤重金属Cr元素含量的定量探测方面是完全可行的.

Detection of heavy metal Cr in soil by the femtosecond filament induced breakdown spectroscopy

In this paper, the element content detection of heavy metal Cr in soil is investigated experimentally by femtosecond filament induced breakdown spectroscopy (FIBS). The plasma filament length is measured using the fluorescence method, and the spatial distribution of Cr 425.5 nm spectral intensity is obtained at lens focal lengths 150 mm and 1000 mm. A calibration curve of the heavy metal element Cr in the soil is obtained based on experimental results. Results demonstrate that the relative deviation of the quantitative analytic result from the standard value is smaller than 5%, and the detection limit of Cr in soil is 7.85 ppm at the laser repetition rate 1 kHz. The femtosecond laser filaments induced breakdown spectroscopy is entirely feasible for quantitative detection of heavy metal element Cr in the soil.
Keywords： femtosecond laser filament laser induced breakdown spectroscopy heavy metal Cr limit of detection