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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.
321

Bioremediation of soils polluted by heavy metals using organic acids

Wasay, Syed A. January 1998 (has links)
No description available.
322

A laboratory study on the development and testing of a bioaugmentation system for contaminated soils /

Mehmannavaz, Reza. January 1999 (has links)
No description available.
323

THE EFECTS OF SOIL PROPERTIES AND CLAY MINERALS ON THE BIOREMEDIATION OF SOILS CONTAMINATED WITH PENTACHLOROPHENOL

Don-Pedro, Esther 23 September 2005 (has links)
No description available.
324

Assesment of Bioremediation Efficiency of Indigenous Bacteria and Plants at an Abandoned Acid Mine Drainage Site

Sivaram, Sushil 13 December 2010 (has links)
No description available.
325

Treatment of Petroleum Hydrocarbons in Oil-Based Drill Cutting Mud Using BiOWiSH Bioaugmentation Products

Zepeda, Diego Jose Cardenas 01 June 2015 (has links) (PDF)
The efficacy of BiOWiSHTM-Thai Aqua, a commercially discontinued microbial product, in remediating oil based drill-cutting mud (DCM) was researched in this study. Experimentation was performed directly on DCM and on sand contaminated with oil extracted from DCM. A gas chromatograph-mass spectrometrer and a respirometer were used for analysis of total petroleum hydrocarbons (TPH) and CO2 production respectively. Five experiments were analyzed by TPH extraction and analysis; four experiments were analyzed by respirometric analysis. The specific microcosm conditions tested in the experiments were control, nutrient-only control, and bioaugmentation product. This study concluded that there might be potential for bioaugmentation of TPH using BiOWiSHTM-Thai Aqua. However, a more extensive study including multiple replicates of samples over a longer sampling time period is required to make a conclusion. TPH analysis from the Sand Microcosm Experiment suggested that in seven days, the addition of BiOWiSHTM-Thai Aqua improved TPH removal relative to the control by 89% while the nutrient-only control improved by 58%. Respirometric analysis suggested CO2 respiration of glucose overshadowed CO2 respiration from biodegradation. Thus, major conclusions could not be made from the respirometric analysis.
326

Clarification of Recreational Pool Water Using Biological Additives Produced by BiOWiSH(TM)

Wilson, Reese Nathaniel 01 June 2015 (has links) (PDF)
Effects of commercially available bacterial products were investigated on two common recreational pool contaminants: sunscreen and cyanuric acid (CYA). Microbial products developed by BiOWiSH Technologies, Inc. were tested for enhancing mechanical filtration and water clarification in bench-scale bioreactors, with conditions mimicking those of recreational pool water. Bacterial consortia included proprietary mixes of Bacillus, Lactobacillus and Pseudomonas, and other genera of bacteria. BiOWiSH products are either fermented on a solid substrate consisting of rice bran and soy meal, or they are mixed with a soluble diluent. Twenty-nine BiOWiSH products were tested throughout forty experiments. Experiments were carried out to determine both the efficacy of BiOWiSH products for turbidity reduction and the mechanism by which BiOWiSH removes sunscreen from solution. In trials without mechanical filtration, the only product which showed a reduction in turbidity relative to the control, albeit inconsistently, was the solid substrate version of BiOWiSH Aqua FOGTM (Thai FOG). Experiments on BiOWiSH coupled with mechanical filtration showed a 79% average reduction of turbidity in the first 24 hrs. BiOWiSH products containing solid substrate, both active and abiotic, showed an average turbidity reduction of 90% in the first 24 hrs. In the same timeframe, soluble BiOWiSH products showed a 79% average reduction in turbidity. Thus, the solid v substrate provided an additional 11% reduction in turbidity over soluble products and un-amended mechanical filtration. Through experimentation and scanning electron microscopy, it was concluded that the primary mechanism of clarification by the solid substrate is adsorption of sunscreen to the substrate surface. Further experiments were performed in anaerobic and aerobic environments to determine whether BiOWiSH products can remove cyanuric acid from solution through adsorption or biodegradation. Two measurement methods, turbidimetric and HPLC (high performance liquid chromatography) were used to independently quantify CYA. A reverse-phase HPLC method was developed which utilizes a phosphate buffer and methanol for the separation of cyanuric acid from nitrate and other chemical species. The solid BiOWiSH Aqua FOG product (prod. in Thailand) interfered with the turbidimetric analysis, showing false decreases in CYA. Using HPLC, there was no measureable biodegradation or adsorption of CYA by BiOWiSH products in these bench-scale tests. Significant systematic error in the HPLC analysis prevented conclusive findings; therefore, the ability of BiOWiSH products to reduce CYA from solution remains inconclusive.
327

Investigation of a Sulfur-Utilizing Perchlorate-Reducing Bacterial Consortium

Conneely, Teresa Anne 13 May 2011 (has links)
We present research investigating how, with in depth knowledge of the community, microbial communities may be harnessed for bioremediation of hazardous water contaminants. We focused on the bacterial reduction of perchlorate, a common water contaminant. For this we studied the structure and capabilities of a novel sulfur-utilizing, perchlorate-reducing bacterial (SUPeRB) consortium. Initially, we characterized the minimal consortium that retained functional capabilities, using 16S rRNA and functional gene analysis. A diverse functional consortium dominated by Beta-Proteobacteria of the family Rhodocyclaceae and sulfur-oxidizing Epsilon-Proteobacteria was found. We also examined the optimal growth conditions under which perchlorate degradation occurred and uncovered the upper limits of this function. Bacterial isolates were screened for function and the presence of functional genes. We expanded to bioreactor studies at bench- and pilot-scale, and first used a perchlorate-reducing, bench-scale bioreactor to probe the stability of the microbial ecosystem. During stable reactor function, a core consortium of Beta- and Epsilon-Proteobacteria reduced perchlorate and the co-contaminant nitrate. A disturbance of the vi consortium led to a failure in function and to higher system diversity. This suggests that the SUPeRB consortium was not metabolically flexible and high population diversity was necessary for a return to stable function. In a pilot-scale bioreactor we determined that the SUPeRB consortium could stably degrade low levels of perchlorate to below the EPA maximum recommended limit. Field conditions, such as temperature extremes and intermittent perchlorate feed, did not negatively impact overall function. When all reactor consortia were compared we observed that the volume of the reactor and the initial inoculum were not as important to stable reactor function as the acclimatization of the consortium to the system and maintenance of favorable conditions within the reactor. In summary we found that the SUPeRB consortium successfully degraded perchlorate in multiple systems. The study of this novel consortium expands our knowledge of the metabolic capabilities of perchlorate-reducing bacteria and suggests potential evolutionary pathways for perchlorate-reduction by microorganisms. The SUPeRB consortium may be used to establish bioremediation systems for perchlorate and other environmental contaminants.
328

Chemical Oxidation Enhanced Bioremediation of Polycyclic Aromatic Hydrocarbon Contaminated Sediments

Tiang Kwong Dieng, Ian Kennedy 10 May 2003 (has links)
This study evaluated the effect of chemical oxidation on the bioremediation of polycyclic aromatic hydrocarbons (PAHs) contaminated sediments. Sediments were treated in sequential steps: biotreatment, chemical oxidation, and biotreatment. The first biotreatment step was initiated via addition of nutrients, microbial seeds, co-metabolites, and/or Tween 80 (surfactant). The chemical oxidation step was conducted using Fenton?s Reagent, ozonation, and peroxone (combination of ozone and hydrogen peroxide). The objective was to enhance the PAHs bioavailability via oxidation of natural organic matter and transformation of Heavy PAHs into more biodegradable compounds. Biotreatment was reestablished as a final polishing step to further degrade remaining PAHs and more biodegradable oxidation by-products. The proposed mechanism was proven successful for the less contaminated sediment (Scioto River) and not the highly contaminated and chemically more complex sediment (Lake Superior). Given this mechanism only worked for the Scioto River sediment, further research is required to determine the mechanisms limiting treatment.
329

DISTRIBUTION OF METABOLIC CHARACTERISTICS AMONG AEROBIC SOIL BACTERIA AND IMPLICATIONS FOR BIOTRANSFORMATION OF ORGANIC AND METALLIC WASTES

Zhang, Fangmei January 2007 (has links)
No description available.
330

Study of Selenite Resistance in Stenotrophomonas maltophilia Oak Ridge Strain 02 and Pseudomonas sp. PC37

Laskar, Mumtaz B. 08 June 2015 (has links)
No description available.

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