CAREER: Electrohydrostatics, Electrohydrodynamics and Microstructural Evolution During Electrodispersion Precipitation

9700860 Harris这个教师早期职业发展项目的目标是研究电流体动力学的基本原理和在电分散沉淀过程中发生的化学沉淀的传质。该方案解决了控制液-液系统中电雾化和微液滴形成固体颗粒的物理、化学和工程问题。改进液-液系统中电分散沉淀过程的缺点是缺乏对雾化过程的电流体动力学和发生在分散相中的化学沉淀的传质的基本理解。关于液-气系统中悬垂液滴和固定式液滴的电雾化已经产生了大量的文献。然而，很少有研究了解静电和脉冲电场对从喷嘴流出并浸入低介电常数液体的悬垂/固定式液滴和液体流的传导影响。具体的问题包括静电和脉冲电场对垂坠液滴的影响，以及壳而不是微球形成的条件。此外，该研究项目将被整合到PI正在开发的“胶体系统科学与工程”的一系列研究生和本科生课程中。课程将讨论纯溶胶和有机溶胶合成的基础知识，表面科学和工程，以及电场对胶体系统和表面的影响。此外，为了鼓励初高中少数民族学生攻读理工科学位，每年夏天将至少用两周的时间举办理工科夏令营。这项工作将对提高所有液-液电雾化过程的吞吐量以及生产具有可控形态、尺寸和组成的微颗粒产生重大影响。该技术的改进将降低高技术应用陶瓷启动粉的成本。＊＊＊

9700860 Harris The objective of this Faculty Early Career Development project is to study the fundamentals of electrohydrodynamics and mass transfer with chemical precipitation that occur in electro dispersion precipitation processes. This proposal addresses the physical, chemical and engineering issues that govern electro atomization in liquid-liquid systems and the formation of solid particles from microdroplets. The drawback to improving electrodispersion precipitation processes in liquid-liquid systems is the lack of a fundamental understanding about the electrohydrodynamics of the atomization process and the mass transfer with chemical precipitation that occurs in the dispersed phase. A tremendous amount of literature has been generated on the electroatomization of pendant and sessile drops in liquid-air systems. However, very little research has been done to understand the effect of static and pulsed electric fields on conducting pendant/sessile drops and liquid streams emanating from a nozzle and immersed in a low dielectric constant liquid. Specific questions include the effect of static and pulsed electric fields on pendant drops and the conditions under which shells form rather than microspheres. Additionally, this research project will be integrated into a series of graduate- and undergraduate-level courses that the PI is developing on the "Science and Engineering of Colloidal Systems." The courses will discuss the fundamentals of hydrosol and organosol synthesis, surface science and engineering, and the effect of electric fields on colloidal systems and surfaces. The PI also will spend at least two weeks per year during the summer conducting science and engineering camps to encourage junior high and high school minority students to pursue degrees in science and engineering. %%% This work will have a significant impact on increasing the throughput of all liquid-liquid electroatomization processes and on the production of microparticles with co ntrolled morphologies, size, and composition. Improvement of this technology will lower the cost of ceramic starting powders for high technology applications. ***