The Molecular Nature and Dynamics of Solid-Liquid Interface Sorptive Systems

该项目属于分析和表面化学的一般领域，以及分离科学的子领域。本实验计划的主旨是测量液-固界面上的吸附-解吸动力学，以评估这种动力学在液-固分离介质和相关化学体系的行为和性能中的作用。用弛豫动力学技术测量这些动态过程将提供有关吸附和分离机制的信息，界面区域的粘度，以及表面相对于吸附能量的不均匀程度的定量测量。化学修饰的二氧化硅和相关的模型体系将被合成用于这些研究。这些材料将通过傅里叶变换红外光谱、固体核磁共振光谱和元素分析进行充分的表征。溶剂在确定界面极性和粘度中的作用将使用荧光探针技术来确定。这些研究的结果将与这些化学修饰的二氧化硅作为液相色谱固定相的性能相关联。这项研究有望对分离过程的化学和固-液界面吸附系统的一般性质有更好的理解。这项工作应该导致改进的色谱系统的开发，用于分析和制备规模的应用，在科学和技术方面具有广泛的影响。

This project is in the general area of analytical and surface chemistry and in the subfield of separation science. The thrust of this experimental program is to measure the dynamics of sorption-desorption at liquid-solid interfaces in order to assess the role of such dynamics in the behavior and performance of liquid chromatographic separation media and related chemical systems. Measurement of these dynamic processes by relaxation kinetic techniques will provide information concerning the mechanisms of sorption and separation, the viscosity of the interfacial domain, and a quantitative measure of the degree of heterogeneity of surfaces with respect to the energetics of sorption. Chemically modified silicas and related model systems will be synthesized for use in these studies. These materials will be fully characterized by Fourier transform infrared spectrometry, solid state nuclear magnetic resonance spectrometry, and elemental analysis. The role of the solvent in determining the interfacial polarity and viscosity will be determined using fluorescence probe techniques. Results of these studies will be correlated with the performance of these chemically modified silicas as liquid chromatographic stationary phases. This research is expected to yield an improved understanding of the chemistry of separation processes and the general nature of solid-liquid interfacial sorptive systems. This work should lead to the development of improved chromatographic systems for both analytical and preparative scale applications that have broad impact in science and technology.