Part 1. Application of supercritical fluid extraction for enantiospecific determination of chlordane residues in fish tissue. Part 2. Prediction of retention time of long chain alcohol phenyl ethers in density programmed supercritical fluid chromatography. Part 3. Evaluation of biogenic oil based technical fluids.

摘要

This dissertation is divided into three parts, research efforts described in each part focused on a different topic.; The first part was aimed at development and validation of a supercritical fluid extraction (SFE) and two-dimensional gas chromatography (2 D-GC) based methodology for enantiospecific determination of chlordane residues in complex biological tissue samples. This pesticide was used extensively in Midwest and southern United States for structural termite control, until 1988, when its use was disallowed by the U.S.EPA. Continued presence of the pesticide in the environment raises a number of questions regarding the environmental source of the pesticide. Some of the questions can be answered through the enantiospecific determination of chlordane residues in environmental matrices. To over come these limitations the supercritical fluid extraction (SFE) and two-dimensional gas chromatography (2 D-GC) based methodology for enantiospecific determination of chlordane residues was successfully developed and validated.; The second part of the dissertation deals with development of a new approach for forecasting retention factor in supercritical fluid chromatography (SFC). In principle SFC is very versatile separation technique, however, to date it has found only limited use, in part because of difficulties in predicting retention behavior of solutes in SFC. An empirical mathematical approach was developed which permits prediction of retention factor as a function of mobile phase density and column temperature. The approach was arrived at by modeling retention factors and developing appropriate correction factors.; The third part of the dissertation deals with evaluation of biogenic oil derivatives as dielectric fluids in electrical transformers. These materials are free from potentially harmful chemicals such as the polyaromatic hydrocarbons (PAHs) and corrosive sulfur. The study involved synthesis and formulation of varied biogenic esters and evaluation of esters as dielectric fluids. Evaluations involved determination of oxidative stability and dielectric properties of esters before and after extended periods of weathering. The results showed that the methyl esters derived from tallow and formulated with stabilizing agents exhibited stability and electrical characteristics comparable to that of the mineral oil based dielectric fluids.