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A Modeling Study For The Implementation Of In Situ Cometabolic Bioremediation Of Trichloroethylene-Contaminated Groundwater., John A. Christ Dec 1997

A Modeling Study For The Implementation Of In Situ Cometabolic Bioremediation Of Trichloroethylene-Contaminated Groundwater., John A. Christ

Theses and Dissertations

The limitations of conventional groundwater remediation technologies have led to the development of innovative technologies which may achieve national hazardous waste site remediation goals. Before an innovative technology can be implemented in the field, remedial project managers, regulators and other stakeholders require adequate modeling tools to help assess the applicability of the technology at a particular site. This modeling study investigates how an innovative technology, in situ cometabolic bioremediation, might be implemented to remediate a TCE-contaminated site, under different site conditions. A steady-state model is developed which couples an analytical expression to simulate the effect of flow between multiple pumping …


Modeling The Uptake And Transpiration Of Tce Using Phreatophytic Trees, Douglas P. Wise Dec 1997

Modeling The Uptake And Transpiration Of Tce Using Phreatophytic Trees, Douglas P. Wise

Theses and Dissertations

Phytoremediation is a recent addition to the numerous methods used today to remediate ground water contaminants. It is proving more effective and efficient compared to existing remediation techniques. The use of phreatophytes, or water seeking trees, has great potential for phytoremediation. These trees are fast growing, long lived, grow their roots down to the ground water table, transpire large amounts of water, and are proven to actively remove contaminants from the soil horizon. The purpose of this research is to develop quantitative concepts for understanding the dynamics of TCE uptake and transpiration by phreatophytic trees over a short rotation woody …


Evaluation Of The Natural Biodegradation Of Aircraft Deicing Fluid Components In Soils, Laura M. Johnson Dec 1997

Evaluation Of The Natural Biodegradation Of Aircraft Deicing Fluid Components In Soils, Laura M. Johnson

Theses and Dissertations

This research effort was conducted to analyze the biodegradation of propylene glycol (PG) and tolyltriazole in two different soil types; a sandy soil and a high clay soil. Both an automated respirometer and a high performance liquid chromatograph (H PLO) were used in the analysis. Two separate experiments were conducted. In the first experiment, one level of tolyltriazole was added to the soils to determine whether or not there was a difference in the biodegradation rates of tolyltriazole in the two soils. The respirometer results indicated that there was a significant difference between the respiration rates of the microorganisms in …


Hybrid Quantum And Molecular Mechanics Embedded Cluster Models For Chemistry On Silicon And Silicon Carbide Surfaces, James R. Shoemaker Oct 1997

Hybrid Quantum And Molecular Mechanics Embedded Cluster Models For Chemistry On Silicon And Silicon Carbide Surfaces, James R. Shoemaker

Theses and Dissertations

Fabrication of silicon carbide SiC semiconductor devices are of interest for aerospace applications because of their high-temperature tolerance. Growth of an insulating SiO2 layer on SiC is a poorly understood process, and sometimes produces interface defects that degrade device performance. Accurate theoretical models of surface chemistry, using quantum mechanics QM, do not exist because of the huge computational cost of solving Schroedingers equation for a molecular cluster large enough to represent a surface. Molecular mechanics MM, which describes a molecule as a collection of atoms interacting through classical potentials, is a fast computational method, good at predicting molecular structure, …