CAREER: Dynamic Simulations of Reconfigurable Complex Fluids From "Janus" and "Catalytically-Driven" Colloidal Particles

职业：“Janus”和“催化驱动”胶体粒子的可重构复杂流体的动态模拟

• 批准号: 1055284
• 负责人: Ubaldo Cordova
• 金额: $ 40.34万
• 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: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2018-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1055284&HistoricalAwards=false
• 关键词: CAREER; Dynamic; Simulations; Reconfigurable; Complex

Cordova 1055284 This CAREER development plan combines the expertise of the PI in low Reynolds number hydrodynamics and colloidal suspensions to study the emerging field of complex fluids based on suspensions of two-faced Janus particles - particles which have two distinct sides - that depending on their surface functionality could lead to novel material properties, aggregation/self-ordering abilities, or to autonomous behaviors using on-board chemical motors operating far from equilibrium. Research and educational activities are designed to elucidate important aspects of reconfigurable complex fluids - active materials that could change and relax their structure with minimum or no external intervention using as precursors Janus and catalytically-driven colloidal particles. The research efforts are divided in two main tasks. The first one focuses on studying the motion, rheology, and structural organization of Janus particle suspensions guided by a combination of fluid flows and external forces. Different behaviors are expected depending on the interparticle force between the Janus faces of the particles (e.g., hard sphere, attractive, soft). The second research task aims at understanding collective motion of catalytically-driven Janus particle suspensions. A simple colloidal approach to autonomous motion via chemical reactions will be used and implemented based on classic multicomponent diffusion and depletion flocculation theory. Simple elementary dynamic units operating with specific rules and exploiting chemotaxis will be proposed as elements for future reconfigurable materials. These efforts will be accomplished by Brownian/Stokesian dynamics simulations and experiments with collaborating partners. The education and outreach components of the plan aim to involve the participation and education of Hispanics from the K-12 to the graduate level. A graduate course in particle dynamics in anisotropic colloidal suspensions will be developed. Emerging topics in colloidal hydrodynamics will be incorporated into an existing undergraduate fluid mechanics course. Modules illustrating autonomously-moving Janus particles will be developed and implemented using advanced multimedia techniques. Additional education activities include workshops to help students strengthen their communications skills and improve their preparation for the Graduate Record Examination (GRE). Intellectual Merit: This work will provide a level of fundamental understanding of asymmetrically functionalized colloidal particles that has heretofore been missing, a lack which has thus far prevented the full development and use of Janus particle technologies - by leading to improved materials, sensors, and drug delivery. The measurement of their rheological behavior at different particle concentrations and flow conditions will broadly impact research on anisotropic colloids by providing a solid basis, basic tools, and knowledge that can be applied in the processing and use of these technologies. On the other hand, the study of catalytically-driven motion of Janus particles will lead to the discovery of interesting material properties and behaviors, such as synthetic chemotaxis and predator-prey cooperative motions that are usually found in nature. The research plan aims at providing a necessary interrogation of catalytically-driven particle motion using Brownian/Stokesian dynamics simulations, particularly at conditions challenging to address experimentally (e.g., concentrated quantities, limited control volumes). Simple models of dynamic units based on catalytically-driven motion that could be exploited for the design and synthesis of reconfigurable complex fluids are proposed. Broader Impact: The research will substantially impact several scientific and technological communities including colloids and complex fluids, microfluidics and physics of interphases. The integrated research/teaching plan will teach and train underrepresented students in topics related to colloidal sciences and engineering. The site of the project, University of Puerto Rico-Mayagüez (UPRM), will facilitate the participation and education of students from underrepresented groups. The teaching and outreach components of the project involve initiatives in colloidal hydrodynamics, engineering materials, and transport phenomena.

Cordova 1055284该职业发展计划结合了PI在低雷诺数流体力学和胶体悬浮液方面的专业知识，以研究基于双面Janus颗粒悬浮液的复杂流体的新兴领域-颗粒具有两个不同的侧面-取决于其表面功能可能导致新的材料特性，聚集/自排序能力，或使用远离平衡运行的机载化学发动机的自主行为。 研究和教育活动旨在阐明可重构复杂流体的重要方面-活性材料可以改变和放松其结构，使用Janus和催化驱动的胶体颗粒作为前体，最小或没有外部干预。研究工作分为两个主要任务。第一个侧重于研究的运动，流变学和Janus粒子悬浮液的结构组织的流体流动和外力的组合引导。根据粒子的Janus面之间的粒子间力（例如，硬球、吸引球、软球）。第二项研究任务旨在了解催化驱动的Janus粒子悬浮液的集体运动。 一个简单的胶体方法，通过化学反应的自主运动将被使用和实施的基础上经典的多组分扩散和耗尽絮凝理论。简单的基本动态单元操作特定的规则和利用趋化性将被提出作为未来可重构材料的元素。这些努力将通过与合作伙伴的布朗/斯托克斯动力学模拟和实验来完成。该计划的教育和推广部分旨在让从K-12到研究生水平的西班牙裔人参与和接受教育。将开设各向异性胶态悬浮液中粒子动力学的研究生课程。在胶体流体力学的新兴课题将纳入现有的本科流体力学课程。将使用先进的多媒体技术开发和实现模块，说明快速移动的Janus粒子。其他教育活动包括研讨会，以帮助学生加强他们的沟通技巧，提高他们的研究生入学考试（GRE）的准备。智力优势：这项工作将提供一个水平的基本理解的不对称功能化的胶体颗粒，迄今为止一直失踪，缺乏迄今为止阻止了Janus粒子技术的全面发展和使用-通过导致改进的材料，传感器和药物输送。在不同颗粒浓度和流动条件下测量其流变行为将通过提供可应用于这些技术的加工和使用的坚实基础、基本工具和知识，广泛影响各向异性胶体的研究。另一方面，对Janus粒子的催化驱动运动的研究将导致发现有趣的材料性质和行为，例如通常在自然界中发现的合成趋化性和捕食者-猎物合作运动。该研究计划旨在使用布朗/斯托克斯动力学模拟对催化驱动的粒子运动进行必要的询问，特别是在具有挑战性的实验条件下（例如，浓缩的量，有限的控制体积）。 提出了基于催化驱动运动的动态单元的简单模型，可用于可重构复杂流体的设计和合成。更广泛的影响：该研究将对几个科学和技术领域产生重大影响，包括胶体和复杂流体，微流体和界面物理学。综合研究/教学计划将教授和培训代表性不足的学生与胶体科学和工程相关的主题。 该项目的所在地波多黎各-马亚圭斯大学将促进代表性不足群体的学生的参与和教育。该项目的教学和推广部分涉及胶体流体力学，工程材料和运输现象的举措。