Presidential Faculty Fellows/Presidential Early Career Awards for Scientists and Engineers (PFF/PECASE): Atomistic-Level Studies of Complex Fluids

摘要CTS-9629135 近年来，分子模拟背后的理论已经取得了很大的进展，重要的是要认识到，然而，可用的方法仍处于起步阶段，在大规模的问题可以解决之前，还需要做更多的工作。 我目前正在进一步发展分子模拟背后的理论，并为大分子的研究实施新的模拟方法。 我特别感兴趣的是应用这种方法来研究复杂的大分子在受限几何结构中的平衡结构和热力学性质，如在多孔介质，表面或模型生物膜中。 我也应用这种方法来研究相平衡的浓缩和稀释的聚合物溶液，并在微观水平上调查聚合物熔体在简单的流动的流变性能。 这些模拟提供了在原子水平上对这些系统的基本理解，从而导致改进的理论模型和新的工程应用。 我们目前正在研究复杂的，有关节的分子在流体和随机介质中扩散的机制。 为此，我已经开发了strostochastic方法，试图模拟运动的灵活分子通过这样的媒体。 对于几个模型系统，随机方法的结果与非平衡动态模拟的结果的比较是有利的。 我们还发现，冷冻保护剂的混合物可以以协同方式起作用，以形成改进的和独特的冷冻保护剂。 我们已经开发了定量描述这些发现的分子模型，从而为新的冷冻保护剂系统的选择和设计提供了急需的指导方针。 我们在这一领域的工作不仅将对保护生命系统产生影响， 医药产品。 我们的目标之一是设计用于长期储存蛋白质和酶的室温玻璃。 如果这一目标得以实现，就有可能在室温下长时间储存疫苗，从而便利在冷藏存在问题的欠发达地区的使用和分配。 大学教育必须包括以下要素：基本原则，实际应用，实验，自我激励和独立研究。 这些元素并不是工程学科所独有的;它们是任何完整教育计划的重要组成部分。 比以往任何时候都多，与现代技术和通信系统，有可能将教育的所有这些方面纳入我们的本科和研究生课程。 我致力于这样做，不仅在化学工程系，而且在整个校园的水平。

ABSTRACT CTS-9629135 In recent years, much progress has been made in theory behind molecular simulations; it is important to recognize, however, that available methods are still in their infancy and that much more work will be necessary before large scale problems can be addresses. I am currently developing further the theory behind molecular simulations and implementing novel simulation methods for the study of macromolecules. I am particularly interested in applying such methods to investigate equilibrium structural and thermodynamic properties of complex macromolecules in confined geometrics, as in porous media, surfaces or as in model biological membranes. I am also applying such methods to study phase equilibria for both concentrated and dilute polymer solutions, and to investigate at a microscopic level the rheological properties of polymer melts in simple flows. These simulations have provided a fundamental understanding of these systems at the atomic level, thereby leading to improved theoretical models and novel engineering applications. We are currently investigating the mechanisms through which complex, articulated molecules diffuse in fluids and in random media. To this end, I have developed strochastic methods that try to mimic the motion of flexible molecules through such media. For several models systems, comparison of the results of the stochastic approach to those of non-equilibrium dynamic simulations have been favorable. We have also found that mixtures of cryoprotectants can act in a synergetic manner to form improved and unique cryoprotectants. We have developed molecular models that describe quantitatively these findings, thereby providing much needed guidelines for the selection and design of new cryoprotectant systems. Our work in this area will have an impact not only in the preservation of living systems, but also in that of pharmaceutical products. One of our goals is that of designing room-temperature glasses for long-term storage of proteins and enzymes. If that goal is achieved, it will be possible, for example, to store vaccines at room temperature for extended periods of time, thereby facilitating use and distribution in underdeveloped areas where refrigeration is a problem. A college education must comprise the following elements: fundamental principles, realistic applications, experimentation, self motivation and independent research. These elements are not unique to engineering disciplines; they are essential components of any complete educational program. More than ever, with modern technology and communication systems it is possible to incorporate all of these aspects of education into our undergraduate and graduate curricula. I am committed to doing so not only in the department of chemical engineering but also at a campus-wide level.