Interactions, Dynamics and Phase Transitions of Charge-Stabilized Colloidal Suspensions

电荷稳定胶体悬浮液的相互作用、动力学和相变

• 批准号: 9730189
• 负责人: David Grier
• 金额: $ 28.5万
• 依托单位: University of Chicago
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-07-01 至 2002-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9730189&HistoricalAwards=false
• 关键词: Interactions; Dynamics; Phase; Transitions; Charge

9730189 Grier This continuation proposal by Prof. David G. Grier of the James Franck Institute of the University of Chicago describes a research program to study the microscopic origins of bulk properties in charge-stabilized colloidal suspensions. The experimental methods to be employed for these studies will include the use of a combination of optical trapping techniques in conjunction with high- resolution digital video microscopy. There are two thrusts. The primary thrust involves a systematic study of how the pairwise interaction potential depends on key control parameters already identified in previous work by the PI. This will involve the use of the "blinking optical tweezer" technique developed by the PI for measuring colloidal pair potentials. This comprehensive study will provide a basis for reformulating the theory of colloidal interactions. A valid theory of colloidal interactions is of major importance not only for colloid science in general but also for the critical role it plays in applied, industrial problems, such as the stability of suspensions. The second thrust centers on the phase transitions in mono-disperse charge-stabilized suspensions. Previous studies of colloidal phase behavior have taken as their starting point the basic understanding that like-charged spheres repel each other. However, systems whose pair potentials are characterized by attractive tails are predicted to undergo structural phase transitions not available to purely repulsive systems. Studies of the phase transitions of such systems are crucial to the understanding of the structure and dynamics of colloids. %%% This continuation proposal by Prof. David G. Grier of the James Franck Institute of the University of Chicago describes a research program to study the microscopic origins of bulk properties in charge-stabilized colloidal suspensions. The experimental methods to be employed for these studies will include the use of a combination of optical trapping techniques in conjunction with high- resolution digital video microscopy. There are two thrusts. The primary thrust involves a systematic study of how the pairwise interaction potential depends on key control parameters already identified in previous work by the PI. This will involve the use of the "blinking optical tweezer" technique developed by the PI for measuring colloidal pair potentials. This comprehensive study will provide a basis for reformulating the theory of colloidal interactions. A valid theory of colloidal interactions is of major importance not only for colloid science in general but also for the critical role it plays in applied, industrial problems, such as the stability of suspensions. The second thrust centers on the phase transitions in mono-disperse charge-stabilized suspensions. Previous studies of colloidal phase behavior have taken as their starting point the basic understanding that like-charged spheres repel each other. However, systems whose pair potentials are characterized by attractive tails are predicted to undergo structural phase transitions not available to purely repulsive systems. Studies of the phase transitions of such systems are crucial to the understanding of the structure and dynamics of colloids. ***

9730189格里尔（Grier）芝加哥大学詹姆斯·弗兰克学院（James Franck Institute of of Chielt）的戴维·G·格里尔（David G. 这些研究要采用的实验方法将包括将光学诱捕技术与高分辨率数字视频显微镜结合使用。 有两个推力。 主要推力涉及对成对相互作用势如何取决于PI在先前工作中已经确定的关键控制参数的系统研究。 这将涉及使用PI开发的“闪烁光学镊子”技术来测量胶体对电位。 这项全面的研究将为重新制定胶体相互作用理论提供基础。 胶体相互作用的有效理论不仅对胶体科学而言至关重要，而且对于它在应用的工业问题（例如悬浮液的稳定性）中所发挥的关键作用。 第二个推力集中在单分散电荷稳定的悬浮液中的相变。先前对胶体相行为的研究已将其起点视为基本的理解，即相似的球体相互击退。 但是，预计其对具有吸引力的尾部具有吸引力的尾部的系统将进行结构相变，而纯粹的排斥系统则无法使用。 对此类系统相变的研究对于理解胶体的结构和动力学至关重要。 %% %%芝加哥大学詹姆斯·弗兰克学院的David G. Grier教授介绍了一项研究计划，以研究负责稳定的胶体悬架中批量财产的微观起源。 这些研究要采用的实验方法将包括将光学诱捕技术与高分辨率数字视频显微镜结合使用。 有两个推力。 主要推力涉及对成对相互作用势如何取决于PI在先前工作中已经确定的关键控制参数的系统研究。 这将涉及使用PI开发的“闪烁光学镊子”技术来测量胶体对电位。 这项全面的研究将为重新制定胶体相互作用理论提供基础。 胶体相互作用的有效理论不仅对胶体科学而言至关重要，而且对于它在应用的工业问题（例如悬浮液的稳定性）中所发挥的关键作用。 第二个推力集中在单分散电荷稳定的悬浮液中的相变。先前对胶体相行为的研究已将其起点视为基本的理解，即相似的球体相互击退。 但是，预计其对具有吸引力的尾部具有吸引力的尾部的系统将进行结构相变，而纯粹的排斥系统则无法使用。 对此类系统相变的研究对于理解胶体的结构和动力学至关重要。 ***