Interfacial Water from Molecular to Mesoscopic Scale

从分子到介观尺度的界面水

• 批准号: 0211626
• 负责人: Alenka Luzar
• 金额: --
• 依托单位: University of California-San Francisco
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-08-01 至 2005-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0211626&HistoricalAwards=false
• 关键词: Interfacial; Water; Molecular; Mesoscopic; Scale

Alenka Luzar of the University of California, San Francisco, is supported by the Theoretical and Computational Chemistry Program for theoretical research directed toward assessing time scales of water dynamics in restricted environments on different length scales ranging from molecular events of hydrogen bond dynamics to kinetics of surface-induced evaporation on a mesoscopic scale. On the molecular scale, a new methodology to analyze hydrogen bond kinetics will be developed and applied to solutions of selected amino acids and alanine-based oligopeptides with varying chain length. This effort will utilize a combination of formal theory and molecular dynamics simulations, and will involve direct collaboration with neutron scattering experimentalists. On mesoscopic scales, the development of powerful umbrella sampling/Monte Carlo algorithms, in conjunction with a coarse-grained model of confined aqueous systems, will enable calculations of activation barriers for capillary evaporation at increased surface separations. This effort aims to extract a scaling law for the barrier height in order to bridge the gap between macroscopic measurements and limited-size model systems. Finally, in a related project, the occurrence of spontaneous liquid-vapor microphase transitions in a hydrophobic pocket will be explored in molecular dynamics simulations. Outcomes from this research are expected to impact disciplines concerned with dynamic aspects of interfacial water and hydrophobicity, ranging from colloids and materials science to biophysics. Understanding the molecular aspects of water dynamics in restricted geometries is central to variety of problems in biophysics and cell biology. This research is expected to impact a number of fields where the effects of water are important, from the development of new bioactive compounds and improved optical fibers to research into biological structures such as proteins and self-assembling materials studied in nanotechnology. As well, research outcomes will assist in the design of surfaces that have optimized dewetting ability. Such surfaces are promising for practical applications such as rain-repellent coatings.

加州大学旧金山分校弗朗西斯科的Alenka Luzar得到了理论和计算化学项目的支持，该项目的理论研究旨在评估受限环境中不同长度尺度上的水动力学时间尺度，从氢键动力学的分子事件到介观尺度上的表面诱导蒸发动力学。 在分子规模上，将开发一种分析氢键动力学的新方法，并应用于选定的具有不同链长的氨基酸和基于丙氨酸的寡肽的溶液。 这项工作将利用正式理论和分子动力学模拟相结合，并将涉及与中子散射实验学家的直接合作。 在介观尺度上，强大的伞形采样/蒙特卡罗算法的发展，结合一个粗粒模型的封闭的含水系统，将使计算的激活障碍毛细蒸发在增加表面分离。 这项工作的目的是提取的势垒高度的比例律，以弥合宏观测量和有限尺寸的模型系统之间的差距。 最后，在一个相关的项目中，在疏水口袋中自发的液-汽微相变的发生将在分子动力学模拟中进行探索。 这项研究的结果预计将影响与界面水和疏水性的动态方面有关的学科，从胶体和材料科学到生物物理学。 了解水动力学的分子方面的限制几何是核心的各种问题，在生物物理学和细胞生物学。 这项研究预计将影响水的影响很重要的一些领域，从开发新的生物活性化合物和改进的光纤到研究生物结构，如蛋白质和纳米技术中研究的自组装材料。此外，研究成果将有助于设计具有最佳去湿能力的表面。 这样的表面是有希望的实际应用，如防雨涂层。