中文摘要：

Yoshida等人提出的惯性流体模型只能解释脉冲激光烧蚀制备纳米硅晶粒平均尺寸随环境气压的变化规律.在此模型基础上,考虑到烧蚀粒子的初始速度分布（Maxwell分布）,得到了纳米硅晶粒尺寸分布的解析表达式,数值模拟结果与Yoshida等人在不同环境氦气压下制备样品的晶粒尺寸分布的实验统计数据基本相符.还利用修正后的模型对不同环境气体种类（氦、氖、氩）中制备的纳米Si晶粒尺寸分布进行了模拟,模拟结果与实验数据相符.结论可为实现纳米硅晶粒尺寸的均匀可控提供理论依据.

英文摘要：

The inertia fluid model proposed by Yoshida et al. can only interpret the influence of ambient pressure on the average size of nanoparticles prepared by pulsed laser ablation. Basing on the model,the Maxwell velocity distribution of the initial ablated particles is considered,a new analytic expression of the size-distribution of nanoparticles is obtained. The simulation results are consistent with the statistic data from Yoshida＇s experiments under different He pressures. Additionally,the size-distribution of nanoparticles is simulated using the modified model under different ambient gases （He,Ne and Ar）,the simulation results coincide with experimental data. The conclusions may serve as the basis for realizing the uniformity and controllability of Si nanoparticles.