CAREER: Micro-structured Colloidal Suspensions: Nano-scale Hydrodynamics and Macroscopic Rheology and Thermal Conductivity

研究方向：微结构胶体悬浮液：纳米尺度流体动力学和宏观流变学和导热性该研究的中心原理是悬浮中的颗粒或纳米管可以被精确地调整为在电场或磁场下旋转和/或自组装。PI计划利用这一基本概念来研究：1)在外电场诱导下，碳纳米管在严格控制的转矩下被迫旋转时的纳米尺度流体动力学；2)研究电场作用下碳纳米管稀悬浮液流变特性的可逆和剧烈变化；3)研究外电场作用下微结构悬浮液热导率的急剧增加和各向异性。特别是后两个项目，其基本主题是通过诱导胶体的微观结构来制造具有可调热和流动特性的“智能”流体。这种智能流体可以作为微处理器冷却和其他工业应用的高级传热流体，以及离合器、阻尼器和汽车减震器等设备的实际应用。这项研究工作将被整合到一个面向女学生的拓展、教育和指导项目中，女学生历来在工程学领域的代表性不足。与道格拉斯项目（Douglass Project）合作，一个在女子学院建立的STEM外展项目，PI将提供：1)通过“周末学院”为9年级和10年级的女孩提供实际的工程介绍，以及2)深入的实验室体验和对本科生的指导。为周末学院开发的以工程为重点的材料将通过一个互动网页提供给其他学生。提议的研究的总体主题，微结构纳米管和纳米颗粒悬浮液，应该有效地吸引和留住新的学生到工程领域，因为它是新颖的，局部感兴趣的，本质上是多学科的。

CAREER: Micro-structured Colloidal Suspensions: Nano-scaleHydrodynamics and Macroscopic Rheology and Thermal ConductivityThe central principle of the proposed research is that particles or nanotubes in suspension can be precisely tuned to rotate and/or self-assemble under electric or magnetic fields. The PI proposes to use this basic concept to 1) study the nanoscale hydrodynamics of carbon nanotubes forced to rotate under carefully controlled torques induced by an external electric field, 2) investigate the reversible and dramatic changes in the rheological properties of dilute suspensions of carbon nanotubes under electric fields, and 3) study the dramatically increased and anisotropic thermal conductivity of microstructured suspensions under external fields. The latter two projects in particular are related by the underlying theme that "smart" fluids with tunable thermal and flow properties can be made by inducing microstructure in colloids. Such smart fluids could have practical applications as advanced heat-transfer fluids for micro-processor cooling and other industrial applications, as well as in such devices as clutches, dampers, and automotive shock absorbers. The research effort will be integrated into an outreach, educational, and mentoring program aimed at female students, who are historically under-represented in engineering. In collaboration with the Douglass Project, an established STEM outreach program at a women's college, the PI will provide: 1) a hands-on introduction to engineering to 9th-and 10th-grade girls through "Weekend Academies," and 2) in-depth laboratory experiences and mentoring for undergraduate women. The material that is developed for the Weekend Academies focusing on engineering will be made available to other students through an interactive web page. The general theme of the proposed research, micro-structured nanotube and nanoparticle suspensions, should be effective at attracting and retaining new students to engineering, because it is novel, of topical interest, and inherently multidisciplinary in nature.