Hohreiter V, Hahn D W
Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, Florida 32611-6300, USA.
Anal Chem. 2006 Mar 1;78(5):1509-14. doi: 10.1021/ac051872s.
The interaction between laser-induced plasmas and individual particles controls the rate of particle dissociation and subsequent atomic diffusion and emission processes, with implications for single-particle spectroscopy, as well as materials synthesis and other plasma sources. It is demonstrated through quantitative plasma imaging studies that discrete particles dissociate on a time scale of tens of microseconds within plasmas formed by 300-mJ Nd:YAG laser pulses. Significant spatial nonhomogeneity, as measured by localized atomic emission from particle-derived calcium atoms, persists on a comparable time scale, providing a measure of their average atomic diffusion rate of 0.04 m(2)/s. In addition, the resulting calcium atomic emission is explored using image analysis as well as traditional spectroscopic analysis.
激光诱导等离子体与单个粒子之间的相互作用控制着粒子解离速率以及随后的原子扩散和发射过程，这对单粒子光谱学以及材料合成和其他等离子体源都有影响。通过定量等离子体成像研究表明，离散粒子在由300 mJ钕钇铝石榴石激光脉冲形成的等离子体内，在几十微秒的时间尺度上解离。通过粒子衍生的钙原子的局部原子发射测量得到的显著空间不均匀性在相当的时间尺度上持续存在，这提供了它们平均原子扩散速率为0.04 m²/s的量度。此外，利用图像分析以及传统光谱分析对产生的钙原子发射进行了研究。
