UNS: Collaborative Research: Dynamics of Active Particles in Anisotropic Fluids

UNS：合作研究：各向异性流体中活性粒子的动力学

• 批准号: 1510949
• 负责人: Ubaldo Cordova
• 金额: $ 16.81万
• 依托单位: University of Puerto Rico Mayaguez
• 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: 2015-08-15 至 2020-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1510949&HistoricalAwards=false
• 关键词: UNS; Collaborative; Research; Dynamics; Active

1510949(Cordova) & 1508987(Abbott)The goal of the proposed research is to investigate with both experiments and computations the behavior of complex, anisotropic active fluids. Active fluids are fluids that behave in unique ways, because of the presence of active particles that can self-assemble, or can move and pack in different ways, giving different macroscopic properties to the fluid. The proposed research can uncover novel phenomena that could be exploited for design new fluid materials that are responsive to their external environment. Past studies have focused largely on the physics of "active colloids" in isotropic Newtonian fluids, yet many future applications of active fluids would require an understanding of their behavior in complex fluids. This is the white space that this proposal covers: how anisotropy in the viscoelastic properties of a fluid can impact fundamental transport phenomena involving active colloids. A first research thrust will focus on the effect of the anisotropic environment of a liquid crystal suspension has on the diffusivity of a self-propelled particle within the suspension. Specifically, Brownian Dynamics (BD) simulations will be combined with experiments involving tracking of single self-propelled colloidal Janus particles at the interface of a nematic liquid crystal. A second thrust will focus on the effects of a suspension of active particles hosted within an anisotropic fluid on the diffusion of passive tracer particles. Motile bacteria dispersed within biocompatible liquid crystals will be used to explore how passive particles diffuse in the presence of the motion of the rod-shaped bacteria. The overall outcome of this integrated program of experiment and simulation will be new knowledge regarding fundamental transport processes driven by internally generated gradients in complex fluids. The collaborating group will establish a collaboration with the Teacher Preparation Program at the University of Puerto Rico Mayaguez to develop, disseminate and assess bilingual educational modules. Educational activities are proposed to expose students to cross-cultural educational experiences and to prepare them to work in diverse settings. An interdisciplinary class on soft matter will be offered to students at both institutions.

1510949（Cordova）和1508987（雅培）拟议研究的目的是通过实验和计算复杂的各向异性活性流体的行为进行研究。活性流体是以独特方式行为的流体，因为存在可以自组装或可以以不同方式移动和包装的活性颗粒，从而为流体提供了不同的宏观特性。拟议的研究可以揭示可用于设计对其外部环境响应的新流体材料的新型现象。过去的研究主要集中在各向同性牛顿流体中的“活性胶体”的物理学上，但是许多未来活性液的应用将需要了解它们在复杂的液体中的行为。这是该提案涵盖的空白：流体的粘弹性特性中的各向异性如何影响涉及活性胶体的基本运输现象。第一个研究推力将集中于液晶悬浮液的各向异性环境对悬浮液中自呈现粒子的扩散性的影响。具体而言，布朗动力学（BD）模拟将与涉及列液晶界面处的单个自螺旋胶体janus颗粒跟踪的实验相结合。第二个推力将集中在各向异性流体中宿主的活性颗粒的悬浮液对被动示踪剂颗粒扩散的影响。分散在生物相容性液晶内的运动细菌将用于探索在棒状细菌的运动中被动颗粒如何扩散的。这个实验和模拟综合程序的总体结果将是关于由复杂流体中内部生成的梯度驱动的基本运输过程的新知识。合作小组将与波多黎各玛雅格斯大学的教师准备计划建立合作，以开发，传播和评估双语教育模块。提出教育活动，以使学生接触跨文化的教育经验，并准备在各种环境中工作。两个机构的学生将提供有关软件的跨学科课程。