中文摘要：

为了提高土壤中激光诱导土壤等离子体光谱的质量，以纳秒脉冲激光作为激发源，研究了CsCl作为土壤样品添加剂对等离子体辐射特性的影响。实验结果表明，在激光能量为200mJ的条件下，CsCl添加剂能够明显增强等离子体的辐射强度。对于土壤样品中的元素Al、Fe和Ti，添加剂含量为20％的谱线强度比无添加剂时的分别提高了42％、39％和54％，光谱信背比分别提高了8％、24％和28％，而且元素Fe和Ti的光谱线宽度变窄了。对激光能量分别为300mJ和400mJ条件下的等离子体光谱也进行了研究。

英文摘要：

In order to improve the spectrum quality of laser-induced plasma,the effect of CsC1 additive to soil sample on the radiation characteristics of plasma is studied. Nanosecond pulse laser is used as the ex- citation source. The experimental results show that the CsCI additive can obviously enhance the radiation intensity of the plasma under the condition that the laser energy is 200 mJ. When the CsC1 with amount of 20% is added,the spectral intensities of elements A1,Fe and Ti are increased by 42% ,39% and 54% compared with the soil without additive, while the spectral signal-to-background ratios increase by about 8% ,24% and 28% ,respectively,and the widths of the spectral lines of elements Fe and Ti become narrow. Besides,the plasma spectra induced by 300 mJ and 400 mJ laser energy are also studied.