UNS: Exploiting novel surface rheology to probe and tailor 2D suspension dynamics

UNS：利用新颖的表面流变学来探测和定制​​二维悬浮动力学

• 批准号: 1512833
• 负责人: Todd Squires
• 金额: $ 28.96万
• 依托单位: University of California-Santa Barbara
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-06-15 至 2019-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1512833&HistoricalAwards=false
• 关键词: UNS; Exploiting; novel; surface; rheology

The goal of the proposed research is to discover and understand phenomena that occur in two-dimensional suspensions of particles. These are particles that are suspended in solutions that are so spread-out that they form what are known as monolayer suspensions. This is a very fundamental problem with industrial and biological implications, since such suspensions are very common in both industry and nature, including emulsions and foams, cells, organelles and biological fluids. The proposal is focused on the understanding of the rheological behavior of particulate dispersions embedded in insoluble monolayers of surfactants. Carefully conceived theoretical and experimental studies of model two-dimensional particulate dispersions are proposed. It is very important to note that the choice of a 2D system was made so that study of the lubrication phenomena in flows between approaching particles can reveal new modes of behavior in interfacial suspensions that have no analog in conventional three dimensional suspensions. In other words, this is a case where the investigation of a 2D system offers as rich a field of exploration and relevance to the real world as the investigation of 3D systems. The proposed research will involve theoretical analysis of a series of paradigmatic problems (e.g. lubrication flows and colloidal pair dynamics) involving monolayers whose surface rheology thickens, thins, or exhibits phase transitions as a function of surface pressure. It will also involve complementary experiments using photolithographically-designed particles and structures dispersed within surfactant monolayer. Exploratory experimental studies of concentrated 2D suspensions, including detailed particle dynamics, effective rheology, and discontinuous shear thickening will be conducted. Outreach and dissemination of research is planned, involving URM students in research. In addition, there are activities planned to reach out to 4th-6th grade students and attract them to mechanical, computer, and chemical engineering.

这项研究的目标是发现和理解二维粒子悬浮液中发生的现象。这些颗粒悬浮在溶液中，分散开来，形成所谓的单层悬浮液。这是具有工业和生物学意义的非常基本的问题，因为这样的悬浮液在工业和自然界中非常常见，包括乳液和泡沫、细胞、细胞器和生物流体。该提案的重点是嵌入在表面活性剂的不溶性单层的颗粒分散体的流变行为的理解。精心构思的模型二维颗粒分散体的理论和实验研究。非常重要的是要注意，选择了2D系统，以便研究接近颗粒之间的流动中的润滑现象，可以揭示界面悬浮液中的新行为模式，这些模式在传统的三维悬浮液中没有类似物。换句话说，在这种情况下，2D系统的研究提供了与3D系统的研究一样丰富的探索领域和与真实的世界的相关性。拟议的研究将涉及一系列的范式问题（如润滑流动和胶体对动力学）的理论分析，涉及单层的表面流变增厚，变薄，或表现出相变作为表面压力的函数。它还将涉及使用分散在表面活性剂单层内的微图形设计的颗粒和结构的补充实验。探索性实验研究的浓缩2D悬浮液，包括详细的颗粒动力学，有效的流变学，和不连续的剪切增稠将进行。计划进行研究的推广和传播，让城市资源管理大学的学生参与研究。此外，还计划开展活动，以接触4 - 6年级的学生，吸引他们学习机械，计算机和化学工程。