Studies of Chemical Rates Processes by Means of Size and Charge Resolved 2D-NMR

在这个项目中，在化学系物理化学计划的支持下，北卡罗来纳大学教堂山分校的C.Johnson教授将在扩散有序二维核磁共振波谱领域进行研究。这项研究将致力于技术和仪器的发展，以及它们在化学交换效应、涉及表面活性剂和大分子以及胶束和胶束的结合平衡方面的应用。还将继续开发迁移率有序的二维核磁共振波谱，特别重视电动研究和数据分析，以研究大小在50至200纳米之间的囊泡的扩散和迁移率。凝聚介质的核磁共振谱中观察到的弛豫速率受摩擦效应的影响，摩擦效应是由分子在介质中平移和重定向运动时的大小和形状决定的。最近发展起来的扩散有序二维核磁共振波谱技术可以识别混合物的分子组成，并同时表征聚集体的大小和存在的其他结构。使用这种技术的一种变体，迁移率有序的二维核磁共振光谱，人们能够识别和确定离子在凝聚介质中的迁移率。约翰逊教授的研究对这些方法进行了改进，并将其扩展到三维领域。

In this project, supported by the Physical Chemistry Program of the Chemistry Division, Prof. C. Johnson of the University of North Carolina at Chapel Hill will conduct research in the area of diffusion-ordered two-dimensional nuclear magnetic resonance spectroscopy. This research will be devoted to the development of techniques and instrumentation, and their applications to chemical exchange effects, binding equilibria involving surfactants and macromolecules, and micelles and micellanes. Work will also be done on the continued development of mobility-ordered two-dimensional nuclear magnetic resonance spectroscopy with special emphasis on electrokinetic studies and data analysis for the diffusion and mobility of vesicles ranging in size from 50 to 200 nanometers. %%% The relaxation rates observed in nuclear magnetic resonance spectra of condensed media are affected by frictional effects determined by the sizes and shapes of molecules as they undergo translational and reorientational motions in the medium. The recently developed technique of diffusion-ordered two-dimensional nuclear magnetic resonance spectroscopy allows the identification of molecular components of mixtures and the simultaneous characterization of the sizes of aggregates and other structures present. Using a variation of this technique, mobility-ordered two-dimensional nuclear magnetic resonance spectroscopy, one is able to identify and determine the mobilities of ions in condensed media. The research by Professor Johnson serves to improve on these methods and extend them into the three dimensional domain.