Studies of Thermal Motions in Liquids and Polymer Systems

罗伯特·佩科拉得到了理论和 计算化学计划继续他的研究， 液体和聚合物系统中的运动。 各种光散射 使用诸如法布里-珀罗干涉测量法的技术， 光相关光谱和总强度光散射 和瞬态电双折射衰减。 两者的动态 刚性和半刚性棒状分子的稀溶液和非稀溶液 包括多肽、胶原蛋白、小杆状蛋白， 寡核苷酸和DNA片段将被研究。 的影响 相互作用和纠缠将被调查，和缓慢的性质 模式将被阐明。 研制了一种模型复合液 它由小的涂覆的二氧化硅球和刚性聚合物组成， 浸泡在溶剂中。 本系统也将以动态光为研究对象 散射和瞬态电双折射衰减。 复合液体是一类普遍存在的材料，其包含 聚合物、颗粒和溶剂。 它们被用作陶瓷前体， 润滑剂、油漆和涂料、粘合剂和色谱分析 列. 由于其复杂性和缺乏适当的模型系统， 在这样的系统中，物种之间的相互作用并不好 明白 Pecora构建了一个棒/球复合液体模型 其动力学可以在两者的广泛组成范围内进行研究 使用一种称为动态的实验技术 光散射

Robert Pecora is supported by a grant from the Theoretical and Computational Chemistry Program to continue his research involving motions in liquid and polymer systems. A variety of light scattering techniques are used such as Fabry-Perot interferometry and photocorrelation spectroscopy as well as total intensity light scattering and transient electric birefringence decay. The dynamics of both dilute and nondilute solutions of rigid and semirigid rodlike molecules including polypeptides, collagen, small rodlike protein, oligonucleotides, and DNA fragments will be studied. The effect of interaction and entanglement will be investigated, and the nature of slow modes will be elucidated. A model composite liquid has been developed which consists of small coated silica spheres and a rigid polymer immersed in a solvent. This system will also be studied by dynamic light scattering and transient electric birefringence decay. Composite liquids are a ubiquitous class of materials which contain polymer, particles and solvent. They are used as ceramic precursors, lubricants, paints and coatings, adhesives, and in chromatographic columns. Due to their complexity and the lack of adequate model systems, the interactions between the species in such systems are not well understood. Pecora has constructed a model rod/sphere composite liquid whose dynamics can be studied over a wide range of composition of both the rods and the spheres using an experimental technique known as dynamic light scattering.