CAREER: Static Properties and Dynamical Behavior of Jammed Systems

这个职业项目将研究复杂流体的微观和宏观性质之间的联系。所研究的体系是“堵塞”的材料，包括胶体悬浮液、乳状液和颗粒状悬浮液。所有这些材料都具有相似的微观性质，最近的理论认为，它们都有一个潜在的“卡住”状态的转变，类似于玻璃转变。这项工作的目的是利用显微镜为测试和扩展干扰理论提供关键的细节。实验将把这些体系的流变性与微观结构的形成和动力学联系起来。主要目标是阐明堵塞的潜在机制，这将与大量研究颗粒材料、胶体、玻璃化转变和复杂流体中的非线性动力学的研究人员高度相关。此外，这些实验的洞察力将有助于加工具有重要工业意义的材料。参与培训的本科生和研究生将接受实验技术和计算机数据分析方面的广泛培训。由于这些系统的跨学科性质以及它们与技术和工业流程的相关性，参与该项目的学生将为在学术界、行业或政府的职业生涯接受良好的培训。该项目与化学和运输系统司的颗粒和多相过程计划共同支持。这个职业项目将研究复杂流体的小尺度结构和它们的大尺度流动行为之间的联系。所研究的体系是“堵塞”的材料，包括胶体悬浮液(液体中的小固体颗粒)、乳状液(第二个液体中的液滴)和颗粒颗粒(大固体颗粒)。所有这些材料都具有类似的小尺度特性，最近的理论表明，它们都有一个潜在的向“卡住”状态的转变，类似于玻璃在冷却后变成固体的过程。这项提议的目的是使用显微镜为测试和扩展干扰理论提供关键的细节。实验将这些材料在管道中流动或在外力作用下变形时的行为与微观结构的形成和运动联系起来。这些实验的洞察力将有助于加工具有重要工业意义的材料(如食品、油漆、药品和石油)。参与其中的本科生和研究生接受了广泛的实验技术和计算机数据分析方面的培训。由于这些系统的跨学科性质以及它们与技术和工业流程的相关性，参与该项目的学生将为在学术界、行业或政府的职业生涯接受良好的培训。该项目与化学和运输系统司的颗粒和多相工艺方案共同支持。

This CAREER project will investigate connections between the microscopic and macroscopic properties of complex fluids. The systems studied are "jammed" materials, including colloidal suspensions, emulsions, and granular suspensions. All these materials possess similar microscopic properties, and recent theories propose that they share an underlying transition to the "jammed" state, analogous to a glass transition. The objective of this work is to utilize microscopy to provide crucial details for testing and extending theories of jamming. Experiments will connect the rheological behavior of these systems to the formation and dynamics of microscopic structures. The overarching goal is to clarify the mechanisms underlying jamming, which will be highly relevant to a large number of researchers studying granular materials, colloids, glass transitions, and nonlinear dynamics in complex fluids. Moreover, the insight from these experiments will be useful to the processing of industrially important materials. Undergraduate and graduate students involved will receive broad training in experimental techniques and computer data analysis. Because of the interdisciplinary nature of these systems as well as their relevance to technological and industrial processes, students involved in the project will be well trained for careers in academe, industry, or government. The project is co-supported with the Particulate and Multiphase Processes Program in the Division of Chemical and Transport Systems.This CAREER project will investigate connections between the small-scale structure of complex fluids and their large-scale flow behavior. The systems studied are "jammed" materials, including colloidal suspensions (small solid particles in a liquid), emulsions (liquid droplets in a second liquid), and granular particles (large solid particles). All these materials possess similar small-scale properties, and recent theories propose that they share an underlying transition to the "jammed" state analogous to how glasses become solid upon cooling. The objective of this proposal is to use microscopy to provide crucial details for testing and extending theories of jamming. Experiments connect the behavior of these materials as they flow through tubes or deform under applied forces, to the formation and motion of microscopic structures. The insight from these experiments will be useful to the processing of industrially important materials (such as food products, paints, pharmaceuticals, and oil). Undergraduate and graduate students involved receive broad training in experimental techniques and computer data analysis. Because of the interdisciplinary nature of these systems as well as their relevance to technological and industrial processes, students involved in the project will be well trained for careers in academe, industry, or government. The project is co-supported with the Particulate and Multiphase Processes Program in the Division of Chemical and Transport Systems.