PECASE: Direct Measurement and Manipulation of Colloidal Interactions and Dynamics in Template Directed Photonic Crystal Assembly

abstractcts - 0346473 m。职业：模板定向光子晶体组装中胶体相互作用和动力学的直接测量和操纵本提案涉及在界面模板和存在外场的情况下，单光子胶体晶体组装中胶体相互作用的测量和操纵。目的是了解在界面“自组装”和“驱动组装”过程中，胶体力和流体动力相互作用与形成热力学结构和动力学途径之间的基本机制。这项工作的核心任务是结合全内反射、视频和共聚焦扫描激光显微镜技术来测量颗粒-颗粒、颗粒-模板和颗粒-场在日益复杂的界面胶体系统中的相互作用，范围从单个颗粒到集中的三维分散体。由于能够直接测量多体界面相互作用，与模板基板上胶体晶体自组装相关的弱引力将通过精细调节温度和特定离子依赖的聚合物分散力来控制。为了避免不可逆凝胶和滞留玻璃结构的形成，中间亚稳态晶体结构的交流电泳驱动组装将用于控制光子晶体组装过程中的动力学路线。蒙特卡罗和斯托克动力学模拟将用于了解如何形成最佳平衡粒子构型以及如何控制动力学以避免动力学陷阱。每个提出的实验都提供了关于如何操纵胶体系统组装大型单界面光子晶体的补充信息，这对于任何寻求在衬底上组装任意纳米和微观结构材料和器件的技术都具有广泛的意义。所提出的职业规划的智力价值是基于其在胶体长度，时间和能量尺度上操纵有序界面结构的基本意义，这些结构本质上是分子和宏观系统的中介，因此对纳米科学和技术至关重要。本提案中的教育计划包括广泛地将我研究小组的显微镜/模拟实验中的图像、视频和动画纳入到本科和研究生的胶体复杂流体/纳米技术课程中。目的是使用可视化和多媒体工具，帮助不同学习风格的学生快速形成必要的心理图像，以保持对胶体科学的物理直观理解。因为我在研究中使用光学显微镜来探索胶体的基本现象，所以直接将图像和视频融入课堂讲课是我用“真实的”多尺度研究实例热情地教授学生的自然方式，这也符合化学工程课程改革的倡议。作为开发可视化工具的一部分，德克萨斯农工大学沉浸式可视化中心的虚拟现实演示将作为特别课堂讲座，也将通过现有的NSF赞助的校园项目，作为对代表性不足的群体、k-12学生和教师的频繁推广工具。为了评估和优化课堂多媒体工具的实施效果，学校心理/教育的合作者。得克萨斯农工大学将帮助评估我基于可视化的讲座的认知和教学方面，研究结果将在教育期刊和国家会议上传播。所提出的职业规划的更广泛的影响与我在课程和拓展项目中直接使用显微镜和模拟视觉效果有关，以提高未来工程师培训的深度、速度、保留和学习的乐趣，并提高公众的科学素养。

AbstractCTS-0346473M. Bevan, Texas A&M UniversityCAREER: Direct Measurement and Manipulation of Colloidal Interactions andDynamics in Template Directed Photonic Crystal AssemblyThis proposal is concerned with measurement and manipulation of colloidal interactions involved in the assembly of single photonic colloidal crystals on interfacial templates and in the presence of external fields. The objective is to understand fundamental mechanisms linking colloidal forces and hydrodynamic interactions to formation of thermodynamic structures and kinetic pathways in interfacial "self-assembly" and "driven assembly" processes. A central task in this work is to combine total internal reflection, video, and confocal scanning laser microscopy techniques to measure particle-particle, particle-template, and particle-field interactions in increasingly complex interfacial colloidal systems ranging from single particles to concentrated three dimensional dispersions. With the ability to directly measure many-body interfacial interactions, weak attractive forces relevant to colloidal crystal self-assembly on templated substrates will be controlled by finely tuning temperature and specific ion dependent polymeric dispersion forces. To avoid formation of irreversible gel and arrested glass structures, AC electrophoretic driven-assembly of intermediate metastable crystalline structures will be used to manipulate the kinetic route in photonic crystal assembly processes. Monte Carlo and Stokesian dynamics simulations will be used to understand how to form optimal equilibrium particle configurations and how to control dynamics to avoid kinetic traps. Each proposed experiment provides complementary information on how to manipulate colloid systems to assemble large single interfacial photonic crystals, which has broad significance for any technology that seeks to assemble arbitrary nano- and micro- structured materials and devices on substrates. The intellectual merit of the proposed career plan is based on its fundamental significance to manipulating ordered interfacial structures on colloidal length, time, and energy scales, which are inherently intermediate to molecular and macroscopic systems and therefore of utmost importance to nano- science and technology.The educational plan in this proposal involves extensively incorporating image, video, and animations from microscopy/simulation experiments in my research group into a colloidal complex fluids/nanotechnology course for both undergrad and grad students. The objective is to use visualization and multimedia tools to help students with different learning styles quickly develop mental pictures necessary to retain a physically intuitive understanding of colloid science. Because I employ optical microscopy to explore fundamental colloidal phenomena in my research, directly incorporating images and videos into class lectures is a natural way for me to passionately teach students using "real" multiscale research examples, which is also consistent with chemical engineering curriculum reform initiatives. As part of developing visualization tools, a virtual reality presentation in the Immersive Visualization Center at Texas A&M will be delivered as a special class lecture, and will also be used as a frequent outreach tool to underrepresented groups, k-12 students, and teachers through existing NSF sponsored campus programs. To assess the effectiveness and optimize the implementation of classroom multimedia tools, collaborators in School Psych./Ed. Tech. at Texas A&M will help to evaluate cognitive and pedagogical aspects of my visualization based lectures, with findings disseminated in education journals and at national conferences. The broader impact of the proposed career plan is related to the direct use of microscopy and simulation visuals from my research in courses and outreach programs to improve the depth, rate, retention, and enjoyment of learning in the training of future engineers and in improving scientific literacy of the general public.