Fluctuations and Structure at Liquid-Liquid Interfaces

液-液界面的波动和结构

• 批准号: 0092469
• 负责人: Mark Schlossman
• 金额: $ 34.5万
• 依托单位: University of Illinois at Chicago
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-02-15 至 2005-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0092469&HistoricalAwards=false
• 关键词: Fluctuations; Structure; Liquid; Interfaces

Synchrotron x-ray surface scattering and Brewster angle microscopy will be used in a program of research and education to investigate fluctuations and structure at the liquid-liquid interface. Students will be trained to use cutting-edge synchrotron techniques to study interfacial phenomena. This research addresses the poorly understood area of molecular ordering and structure at liquid-liquid interfaces. This interdisciplinary area has important consequences for understanding inhomogenieties in condensed matter systems, and molecular organization at soft interfaces. The results will be relevant to a range of chemical and biological systems. The areas of study are: (1) Molecular ordering and phase transitions in surfactant monolayers at the water-oil interface, (2) Test of a recent hypothesis about the role of capillary waves and intrinsic structure in determining the interfacial width between water and alkanes, (3) Determination of the interfacial Hamiltonian through the study of fluctuating interfaces interacting over short distances in thin wetting films; and (4) Development of a new model system suited for structural studies of the adsorption of larger biomolecules to lipid membranes.Surfactant molecules preferentially adsorb to the interface between two liquids, such as oil and water. The surfactants act as a bridge that connects two types of materials that would, otherwise, not mix. These surfactants play an important role in many domestic products, such as shampoos, paints, and plastics. More importantly, surfactants form the basis for biological cell membranes that support the formation of life on earth. From the point of view of condensed matter physics, it is important to understand how large numbers of molecules arrange themselves at interfaces because the makeup of these interfaces determine many important properties of materials. Chemists and biologists are also interested in the way molecules arrange themselves and transport through liquid interfaces. This is important, for example, in the separation of toxic from non-toxic chemicals and in controlling which biological molecules can enter different parts of cells or the liquid region between cells. Due to the importance of these systems they have been studied for many years. However, an understanding of the structure on the molecular length scale is lacking. During the past three years, NSF support has enabled the development of powerful x-ray scattering techniques that directly probe the organization of molecules at the liquid-liquid interface. The present grant supports the training of students in the further development and application of these techniques to areas of physical, chemical, and biophysical interest.

同步加速器X射线表面散射和布鲁斯特角显微镜将用于研究和教育计划，以调查液-液界面的波动和结构。 学生将接受培训，使用先进的同步加速器技术来研究界面现象。 这项研究解决了在液-液界面的分子有序和结构的知之甚少的领域。 这一跨学科领域的理解凝聚态系统中的不均匀性，在软界面的分子组织具有重要的影响。 结果将与一系列化学和生物系统有关。 研究领域包括：（1）水-油界面表面活性剂单分子膜中的分子有序和相变;（2）检验最近关于毛细管波和内在结构在确定水和烷烃之间界面宽度中的作用的假设;（3）通过研究在薄润湿膜中短距离上相互作用的波动界面来确定界面哈密顿量;（4）开发了一种新的模型系统，用于研究较大的生物分子在脂膜上的吸附。 表面活性剂作为一个桥梁，连接两种类型的材料，否则，不会混合。 这些表面活性剂在许多家用产品中起着重要作用，如洗发水，油漆和塑料。 更重要的是，表面活性剂构成了支持地球生命形成的生物细胞膜的基础。 从凝聚态物理学的角度来看，理解大量分子如何在界面处排列是很重要的，因为这些界面的组成决定了材料的许多重要性质。 化学家和生物学家也对分子排列和通过液体界面传输的方式感兴趣。 例如，这在有毒化学物质与无毒化学物质的分离以及控制哪些生物分子可以进入细胞的不同部分或细胞之间的液体区域中是重要的。 由于这些系统的重要性，它们已经被研究了很多年。 然而，缺乏对分子长度尺度上的结构的理解。 在过去的三年中，NSF的支持使强大的X射线散射技术的发展，直接探测在液-液界面的分子组织。 目前的赠款支持培训学生进一步发展和应用这些技术的物理，化学和生物物理感兴趣的领域。