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Detection And Characterization Of Malathion Adherence To Piping Materials Used In Water Distribution Systems, William D. Flemings
Detection And Characterization Of Malathion Adherence To Piping Materials Used In Water Distribution Systems, William D. Flemings
Theses and Dissertations
Protection of the public water supply is a national security priority, and as such, it is important to better understand the fate of a chemical weapons agent injection into a public water distribution system. This study investigated the adherence of malathion to pipe materials that are used in public water distribution systems, with malathion serving as a chemical representative of the organophosphorus nerve agent VX. Copper and iron specimen were exposed to malathion solutions for periods of 4, 8, and 24 hours and then tested for evidence of chemical adherence to the metal surfaces. Nonlinear desiccation profiles revealed total mass …
The Effect Of Malathion On The Activity And Performance Of Activated Sludge, Erik G. Rauglas
The Effect Of Malathion On The Activity And Performance Of Activated Sludge, Erik G. Rauglas
Theses and Dissertations
Decontamination activities following a chemical weapons incident may generate significant quantities of contaminated wash water that may enter the wastewater collection system either intentionally or accidentally. This raises concerns about the effect of chemical warfare agents (CWAs) on the operation of a biological wastewater treatment plant. The goal of the study was to evaluate the effect of malathion on the activity and performance of activated sludge. Malathion is an organophosphate (OP) and is considered an environmental surrogate for VX. This study employed respirometry, short term batch tests, and long term exposure experiments to investigate the effects of different concentrations of …
Effect Of Malathion On The Microbial Ecology Of Activated Sludge, Seth K. Martin
Effect Of Malathion On The Microbial Ecology Of Activated Sludge, Seth K. Martin
Theses and Dissertations
Decontamination activities may cause the release of contaminated washwater into the wastewater that eventually flows into a wastewater treatment facility. This raises concerns about the effect of chemical warfare agents (CWAs) on the microbial consortia that are responsible for cleaning the wastewater. This study investigated the impact of malathion on the microbial ecology of laboratory scale activated sludge communities. The Simpson Reciprocal Index decreased for three bioreactors operated in the absence of malathion, which showed that the microbial assemblage became less diverse during the course of the study. The species identified in the bioreactors belonged to well-known groups of heterotrophic …
The Fate Of Malathion On Copper And Iron Piping Within A Water Distribution System, Walter R. Lee
The Fate Of Malathion On Copper And Iron Piping Within A Water Distribution System, Walter R. Lee
Theses and Dissertations
Thermogravimetry, the study of mass loss as a function of temperature, has been used for oxidation, decomposition, and solid-state studies. This research used a thermogravimetric analyzer (TGA) coupled with Fourier transform infrared (FT-IR) spectroscopy in the study of copper and iron specimens exposed to malathion. Exposure to the malathion solution created a visible silver coating on copper and graphite-flake particles on iron specimens. Thermogravimetric mass loss curves revealed linear and nonlinear decomposition stages associated with mass loss reactions. Copper specimens exposed to malathion exhibited lower activation energy (Ea) values (2.28 to 4.40 kJ mol-1) than for copper specimens exposed to …