利用Nd:YAGns脉冲激光烧蚀土壤标样,由Ar载气流将蒸发物引入到电感耦合等离子体光源,通过光谱仪和采谱系统获得原子发射光谱,测量了样品中重金属元素As、Pb、Cr、Hg和Cd的光谱强度、信背比和谱线宽度,并研究了样品蒸发量和烧蚀颗粒尺寸随实验条件的变化。结果表明,当激光输出能量从100mJ上升至700mJ时,元素的光谱强度和信背比均正比增大,谱线宽度基本不变;样品蒸发量亦随激光能量正比增加,但烧蚀颗粒尺寸增大缓慢。所以,适当增大激光输出能量可以获得更高质量的原子发射光谱。

Nd: YAG nanosecond pulsed laser was used to ablate the soil standard samples. The evaporated material was introduced to inductively coupled plasma source by the argon carrier gas flow. The atomic emission spectrum be obtained through the spectrometer and spectral collecting system. The spectral intensity,the signal-to-background ratio,and the full-width at half-maximum were measured,such as As,Pb,Cr,Hg,and Cd of heavy metal elements in the samples. And the changes of the evaporated samples mass and the ablated particles size with the experimental conditions were investigated. The results show that the spectral intensity and signal-to-background ratio of the elements increase proportionally,the full-width at half-maximum unchanged basically. The evaporated samples also increase proportionally with the laser energy,but the ablated particles size increase slowly when the laser output energy rising from 100mJ to 700mJ. Therefore,the atomic emission spectrum with the higher quality can be obtained by increasing the laser output energy properly.