The Surface Spectroscopy of a Single Aerosol Particle

这项研究将随着三个新光谱仪的发展，将单个悬浮气溶胶粒子的光谱学工作扩展到表面区域。第一种是表面张力光谱学，用于测量表面分子过剩；第二种是电磁测深(使用荧光和二次谐波产生)，以提供有关表面分子取向和内部分子分布的微观信息；第三种是相边界相移光谱学，用于在线测量表面的水凝结速率。这将是首次使用所有三个光谱仪来研究在存在大气中感兴趣的表面活性物种的情况下与水凝结有关的微观效应。通过使用所提出的微粒对撞机，将有助于制备具有特定密度的表面涂层。这一研究将为大气气溶胶物理化学性质的研究提供新的技术手段。

This research will extend work on the spectroscopy of single levitated aerosol particles into the surface region with the development of three new spectroscopies. The first, surface tension spectroscopy, to provide a measure of the surface molecular excess; the second, electromagnetic sounding (using fluorescence and second harmonic generation), to provide microscopic information on molecular orientation at the surface and the distribution of molecules in the interior; and the third, phase boundary phase shift spectroscopy, to provide an on-line measure of the water condensation rate at the surface. This will be the first application of all three spectroscopies to investigate microscopic effects associated with water condensation in the presence of surface active species of atmospheric interest. Preparation of surface coatings having specific densities will be facilitated by the use of a proposed microparticle collider. This research will provide new techniques for the study of atmospheric aerosol physical and chemical property.