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>Part 1. A comparison of enantioselective uptake and degradation of chiral pesticides through biotic and abiotic processes in the aquatic environment and Part 2. Development of a soybean oil based epoxy resin system and its application in composite material fabrication and Part 3. Development of an environmentally benign process for the recovery of scrap polystyrene.
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Part 1. A comparison of enantioselective uptake and degradation of chiral pesticides through biotic and abiotic processes in the aquatic environment and Part 2. Development of a soybean oil based epoxy resin system and its application in composite material fabrication and Part 3. Development of an environmentally benign process for the recovery of scrap polystyrene.
Part one. Many environmental monitoring programs are in place to determine the extent of environmental contamination by synthetic pesticides. However, the stereo-specificity of synthetic pesticides is rarely investigated. A number of these pesticides possess one or more stereogenic centers resulting in two or more enantiomers. The enantiomers may exhibit marked differences in bioactivity. One of the enantiomers may possess the desired biochemical properties, while others may produce deleterious effects. The magnitude of the problem is unknown, and no regulations concerning the enantio-meric purity of pesticides are in place. The present study was initiated to monitor the enantiomeric ratios of pesticide residues in aquatic organisms and determine trends in their environmental persistence as a function of time.; Part two. The vast majority of industrial epoxy resin systems are formulated from hazardous chemicals such as bis-phenol A and epichlorohydride. As petroleum becomes more scarce and costly, attempts have been made to develop resin systems that are made at least in part from low-cost, renewable resources such as vegetable oils. Soybean oil is by far the most prevalent, as well as being non-toxic and biodegradable. The current study investigates the development of effective epoxy resin systems using derivatives of soy oil.; Part three. Polystyrene is a thermoplastic formed by free radical polymerization of styrene monomers. Due to its high volume but low density, foamed polystyrene fills up a significant portion of the nation's landfills. Recycling reduces the amount of this land-fill waste; however, most recycling methods involve crushing or shredding the polymer or dissolving it in a solvent. Many of these solvents are significantly toxic, and some are known carcinogens. The process described here involves dissolving polystyrene foam in a solution of fatty acid esters derived from seed oils, such as soybean oil. The resulting solution can be used as a raw material for a variety of products and processes including, but not limited to, additional polymerization forming interpenetrating polymer networks, coatings, cleansers, viscosity selective lubricants, additives for resin systems used in composite materials, and treatments for lumber products.
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