Surface Order in Dielectric Liquids

非技术摘要由于最近的实验，现在人们知道液体中的原子或分子可以在表面附近排列成层。因此，纳米尺度的表面区类似于液晶，而不是液体本身。该项目的目标是利用同步辐射对这一现象进行详细和系统的研究。从这些研究中获得的知识将有助于确定液体表面性质如何以及为什么与整体液体性质不同。液体表面在许多常见的过程中发挥着重要作用，如波浪、润湿/扩散/涂层、蒸发、云中和其他地方液滴和气溶胶的形成、薄膜技术、工业过程等。因此，这些研究最终可能会使能够更好地理解和控制这些过程而给社会带来好处。该项目将通过在跨学科环境中培训研究生，并向他们提供使用先进光子源和国家同步加速器光源等国家设施的经验，将研究和教学结合在一起。一门名为“流体物理学”的新本科课程正在开发中，有关液体的“材料科学模块”将用于高中。技术摘要目前已知，正常(各向同性)液体，无论是金属的还是非金属的，都能在足够低的温度下形成分层表面区域。本项目的目标是对这些有序现象进行详细和系统的研究。非金属液体中观察到的表面分层与温度和材料性质(如表面张力)的关系将用同步辐射X射线散射进行详细研究。将寻求不同材料分层行为中普遍的定性和定量特征和趋势的识别。这些研究最终可能导致更好地理解和更多地控制无处不在的过程，液体表面在其中扮演着重要的角色。该项目将通过在跨学科环境中培训研究生，并向他们提供使用同步加速器设施的经验，将研究和教学结合在一起。一门名为“流体物理学”的新本科课程正在开发中，有关液体的“材料科学模块”将被制作出来，供高中使用。

Nontechnical abstractAs a result of recent experiments, it is now known that the atoms or molecules in liquids can arrange themselves into layers near the surface. The nanoscale surface region therefore resembles a liquid crystal rather than the liquid itself. The objective of this project is a detailed and systematic study of this phenomenon using synchrotron radiation. The knowledge gained from these studies will help determine how and why liquid surface properties are different from bulk liquid properties. Liquid surfaces play important roles in many familiar processes such as waves, wetting/spreading/coating, evaporation, the formation of droplets and aerosols in clouds and elsewhere, thin film technology, industrial processes, etc. Therefore, these studies may ultimately lead to benefits to society from being able to better understand and control such processes. This project will integrate research and teaching by training graduate students in an interdisciplinary environment, and also by giving them experience in the use of national facilities such as the Advanced Photon Source and the National Synchrotron Light Source. A new undergraduate course called "Physics of Fluid" is being developed, and a "Materials Science Module" about liquids will be produced for use in high schools.Technical abstractNormal (isotropic) liquids, both metallic and nonmetallic, are now known to form stratified surface regions at sufficiently low temperatures. The objective of this project is a detailed and systematic study of these ordering phenomena. The dependence of observed surface layering in nonmetallic liquids on temperature and on properties of the material such as surface tension will be investigated in detail using synchrotron X-ray scattering. Identification of universal qualitative and quantitative features and trends in the layering behavior of different materials will be sought. These studies may ultimately lead to a better understand of, and more control over, the ubiquitous processes in which liquid surfaces play essential roles. This project will integrate research and teaching by training graduate students in an interdisciplinary environment, and also by giving them experience in the use of synchrotron facilities. A new undergraduate course called "Physics of Fluids" is being developed, and a "Materials Science Module" about liquids will be produced for use in high schools.