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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Hydrogenases of Desulfovibrio desulfuricans G20

Ringbauer, Joseph A. January 2000 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 160-168). Also available on the Internet.
122

Molecular characterization of a microbial community from uranium-contaminated acidic sediment

North, Nadia. Balkwill, David. January 2003 (has links)
Thesis (M.S.)--Florida State University, 2003. / Advisor: Dr. David Balkwill, Florida State University, School of Arts and Sciences, Dept. of Oceanography. Title and description from dissertation home page (viewed Apr. 7, 2004). Includes bibliographical references.
123

Fe°-enhanced bioremediation for the treatment of perchlorate in groundwater

Jose Sanchez, Aiza Fernanda, 1972- 07 July 2011 (has links)
Not available / text
124

Practical applications of plasmids : overexpression of a bacterial alkaline phosphatase as a mechanism for heavy metal and radionuclide sequestration

Powers, Leigh Gayle 05 1900 (has links)
No description available.
125

Mathematical Modelling of DNAPL Source Zone Remediation

West, Michael 21 May 2009 (has links)
Mathematical modelling was utilized to evaluate trichloroethylene (TCE) and tetrachloroethylene (PCE) dense non-aqueous phase liquid (DNAPL) source zone remediation in the subsurface environment. Semi-analytical solutions were derived, tested, and employed to evaluate the benefits of source zone concentration reduction and solute degradation mechanisms on the evolution of plumes in porous media and fractured rock domains. Simulations of treatment in complex DNAPL source zones using different remedial technologies were completed with a numerical model that was developed, tested, calibrated, and applied to nine idealized heterogeneous porous media sites. Analytical modelling revealed that, in domains dominated by matrix diffusion, aggressive and moderate source zone concentration reduction may have similar effects on the leading edge of the plume. The tailing (near source) edge of the plume may be more responsive to aggressive concentration reduction, particularly when diffusion processes are negligible. Both the near-field (near-source) and far-field plume responses were strongly influenced by the matrix decay half-life for both transient and steady-state conditions. The degradative capacity of the matrix largely dictated plume extent and life-span for the fractured bedrock site considered here. Numerical simulations of in situ source zone treatment with chemical oxidation (ISCO), enhanced bioremediation (ISEB), and surfactants (SEAR) were compared and contrasted. Treatment efficacy was site specific, with benefits observed at some sites, and detrimental impacts observed at others. Each technology demonstrated some degree of performance enhancement relative to dissolution only (no treatment). The maximum DNAPL mass depletion enhancement factors for ISCO, ISEB and SEAR, were 1.44, 2.91, and 2.70 after 10 years, respectively. Similarly, the maximum boundary mass flux enhancement factors for ISCO, ISEB and SEAR were 9.78, 3.32, and 3.97, respectively. While notable enhancements were observed for many sites during active treatment, the long-term performance of pre-maturely terminated ISCO and ISEB, and to a lesser degree SEAR, was similar to dissolution. Overall, the partial depletion of DNAPL mass from source zones produced on-going persistent boundary mass flux signatures. Only the complete removal of DNAPL mass, which was attained for one site with SEAR, successfully eliminated downgradient boundary mass flux. / Thesis (Ph.D, Civil Engineering) -- Queen's University, 2009-05-21 08:55:04.491
126

A laboratory study on bioremediation of a diesel-contaminated fine-textured soil /

Rana, Nadeem Ahmed. January 1998 (has links)
A laboratory study was conducted to bioremediate a fine textured soil contaminated with diesel. The local microorganisms were stimulated by supplying nutrients with the aid of a water table management system. A fine textured soil, contaminated for more than 20 years, with more than 6500 mg/kg of diesel was packed in fifteen columns, 2 m long and 0.2 m in diameter. Twelve out of fifteen soil columns were subjected to bioremediaton, by supplying nutrients, water and air at desired depths. Three columns were used as a control to monitor passive degradation of contaminant without intervention. / The experiment was designed to employ three different treatments in triplicates. In the first treatment, nutrients, air and water were supplied. In the second, only nutrients and water were applied and in the third, water alone was applied. These treatments were applied by two different water table management strategies. In the first, three columns were remediated by following a full column remediation strategy, while in the second, nine columns were treated in a stagewise manner, by maintaining the water table at 1 m depth from surface. (Abstract shortened by UMI.)
127

Non-Newtonian conversion of emulsion liquid membranes in the extraction of lead and zinc from simulated wastewater

Gilbert, Christopher Donald 12 1900 (has links)
No description available.
128

Microbial activity of a contaminated wetland system under aerobic conditions as a measure of sediment-based intrinsic bioremediation

Wynn, Jennifer C. 12 1900 (has links)
No description available.
129

Microbial reductive dechlorination of hexachloro-1,3-butadiene

Booker, Randall Sulter, Jr. 08 1900 (has links)
No description available.
130

Coupled sorption and transport of nonionic surfactants in natural soils

Chang, Eric Kenneth 05 1900 (has links)
No description available.

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