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Citric Acid-Modified Fenton's Reaction for the Oxidation of Chlorinated Ethylenes in Soil Solution Systems

Description: Fenton's reagent, a solution of hydrogen peroxide and ferrous iron catalyst, is used for an in-situ chemical oxidation of organic contaminants. Sulfuric acid is commonly used to create an acidic condition needed for catalytic oxidation. Fenton's reaction often involves pressure buildup and precipitation of reaction products, which can cause safety hazards and diminish efficiency. We selected citric acid, a food-grade substance, as an acidifying agent to evaluate its efficiencies for organic con… more
Date: March 15, 2008
Creator: Seol, Yongkoo & Javandel, Iraj
Partner: UNT Libraries Government Documents Department
open access

The Genome of the Epsilonproteobacterial Chemolithoautotroph Sulfurimonas dentrificans

Description: Sulfur-oxidizing epsilonproteobacteria are common in a variety of sulfidogenic environments. These autotrophic and mixotrophic sulfur-oxidizing bacteria are believed to contribute substantially to the oxidative portion of the global sulfur cycle. In order to better understand the ecology and roles of sulfur-oxidizing epsilonproteobacteria, in particular those of the widespread genus Sulfurimonas, in biogeochemical cycles, the genome of Sulfurimonas denitrificans DSM1251 was sequenced. This geno… more
Date: August 8, 2007
Creator: Class, USF Genomics; Sievert, Stefan M.; Scott, Kathleen M.; Klotz, Martin G.; Chain, Patrick S.G.; Hauser, Loren J. et al.
Partner: UNT Libraries Government Documents Department
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Monitoring/Verification using DMS: TATP Example

Description: Field-rugged and field-programmable differential mobility spectrometry (DMS) networks provide highly selective, universal monitoring of vapors and aerosols at detectable levels from persons or areas involved with illicit chemical/biological/explosives (CBE) production. CBE sensor motes used in conjunction with automated fast gas chromatography with DMS detection (GC/DMS) verification instrumentation integrated into situational operations management systems can be readily deployed and optimized … more
Date: March 1, 2008
Creator: Weeks, Stephan & Kyle, Kevin
Partner: UNT Libraries Government Documents Department
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Foot & Mouth Disease & Ulcerative/Vesicular Rule-outs: Challenges Encountered in Recent Outbreaks

Description: Foot and mouth disease (FMD) is a highly infectious and contagious viral disease affecting bovidae (cattle, zebus, domestic buffaloes, yaks), sheep, goats, swine, all wild ruminants and suidae. Camelidae (camels, dromedaries, llamas, vicunas) have low susceptibility. Foot and mouth disease is caused by a RNS virus of the family Picornaviridae, genus Aphthovirus. There are seven immunologically distinct serotypes: A, O, C, SAT1, SAT2, SAT3, Asia 1. Foot and mouth disease causes significant econo… more
Date: January 28, 2008
Creator: Hullinger, P
Partner: UNT Libraries Government Documents Department
open access

Bio-/Photo-Chemical Separation and Recovery of Uranium

Description: Citric acid forms bidentate, tridentate, binuclear or polynuclear species with transition metals and actinides. Biodegradation of metal citrate complexes is influenced by the type of complex formed with metal ions. While bidentate complexes are readily biodegraded, tridentate, binuclear and polynuclear species are recalcitrant. Likewise certain transition metals and actinides are photochemically active in the presence of organic acids. Although the uranyl citrate complex is not biodegraded, in … more
Date: March 12, 2008
Creator: Francis, A. J. & Dodge, C. J.
Partner: UNT Libraries Government Documents Department
open access

Comparative genomics of citric-acid producing Aspergillus niger ATCC 1015 versus enzyme-producing CBS 513.88

Description: The filamentous fungus Aspergillus niger exhibits great diversity in its phenotype. It is found globally, both as marine and terrestrial strains, produces both organic acids and hydrolytic enzymes in high amounts, and some isolates exhibit pathogenicity. Although the genome of an industrial enzyme-producing A. niger strain (CBS 513.88) has already been sequenced, the versatility and diversity of this species compels additional exploration. We therefore undertook whole genome sequencing of the a… more
Date: April 28, 2011
Creator: Grigoriev, Igor V.; Baker, Scott E.; Andersen, Mikael R.; Salazar, Margarita P.; Schaap, Peter J.; Vondervoot, Peter J.I. van de et al.
Partner: UNT Libraries Government Documents Department
open access

Bioremediation of soils, sludges, and materials contaminated with toxic metals or radionuclides

Description: Bioremediation stabilizes and reclaims radionuclide or toxic metal-contaminated materials, soils, sediments, or wastes; it then recovers the contaminating radionuclides and metals. Waste materials are stabilized and reduced in volume using anaerobic bacteria; or alternatively, materials are treated with citric acid before bioremediation begins. Photolysis is used after bioremediation to release radionuclides.
Date: April 1, 1993
Creator: Francis, A. J.
Partner: UNT Libraries Government Documents Department
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Genomic Characterization of Methanomicrobiales Reveals Three Classes of Methanogens

Description: Methanomicrobiales is the least studied order of methanogens. While these organisms appear to be more closely related to the Methanosarcinales in ribosomal-based phylogenetic analyses, they are metabolically more similar to Class I methanogens. In order to improve our understanding of this lineage, we have completely sequenced the genomes of two members of this order, Methanocorpusculum labreanum Z and Methanoculleus marisnigri JR1, and compared them with the genome of a third, Methanospirillum… more
Date: May 1, 2009
Creator: Anderson, Iain; Ulrich, Luke E.; Lupa, Boguslaw; Susanti, Dwi; Porat, Iris; Hooper, Sean D. et al.
Partner: UNT Libraries Government Documents Department
open access

Microbial Transformations of Radionuclides and Environmental Restoration Through Bioremediation.

Description: Treatment of waste streams containing radionuclides, the remediation of contaminated materials, soils, and water, and the safe and economical disposal of radionuclides and toxic metals containing wastes is a major concern. Radionuclides may exist in various oxidation states and may be present as oxide, coprecipitates, inorganic, and organic complexes depending on the process and waste stream. Unlike organic contaminants, the metals cannot be destroyed, but must either be converted to a stable f… more
Date: September 29, 2006
Creator: Francis, A. J.
Partner: UNT Libraries Government Documents Department
open access

Twenty-second Fungal Genetics Conference - Asilomar, 2003

Description: The purpose of the Twenty Second Fungal Genetics Conference is to bring together scientists and students who are interested in genetic approaches to studying the biology of filamentous fungi. It is intended to stimulate thinking and discussion in an atmosphere that supports interactions between scientists at different levels and in different disciplines. Topics range from the basic to the applied. Filamentous fungi impact human affairs in many ways. In the environment they are the most importan… more
Date: June 30, 2003
Creator: Walton, Jonathan D.
Partner: UNT Libraries Government Documents Department
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Remediation of heavy-metal-contaminated soil using chelant extraction: Feasibility studies

Description: Results are presented of a laboratory investigation conducted to determine the efficacy of using chelating agents to extract heavy metals (Pb, Cd, Cr, Ba, Cu, and Zn) from soil, the primary focus being on the extraction of lead from the soil. Results from the batch-shaker studies and emphasizes the columnar extraction studies are described. The chelating agents studied included ethylenediaminetetraacetic acid (EDTA) and citric acid, in addition to water. Concentrations of the chelants ranged fr… more
Date: August 1, 1993
Creator: Peters, R. W.; Miller, G.; Taylor, J. D.; Schneider, J. F.; Zellmer, S.; Edgar, D. E. et al.
Partner: UNT Libraries Government Documents Department
open access

Removal and recovery of radionuclides and toxic metals from wastes, soils and materials

Description: A process has been developed at Brookhaven National Laboratory (BNL) for the removal of metals and radionuclides from contaminated materials, soils, and waste sites (Figure 1). In this process, citric acid, a naturally occurring organic complexing agent, is used to extract metals such as Ba, Cd, Cr, Ni, Zn, and radionuclides Co, Sr, Th, and U from solid wastes by formation of water soluble, metal-citrate complexes. Citric acid forms different types of complexes with the transition metals and ac… more
Date: July 1, 1993
Creator: Francis, A. J.
Partner: UNT Libraries Government Documents Department
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Release of organic reagents from solidified decontamination wastes

Description: In order to provide technical information needed by the US Nuclear Regulatory Commission to evaluate the adequacy of near-surface disposal of decontamination wastes, Brookhaven National Laboratory has measured the release of organic reagents from solidified simulated decontamination wastes. The waste streams consisted of either mixed-bed ion-exchange resins or anion exchange resins equilibrated with EDTA, oxalic acid, citric acid, picolinic acid or simulated LOMI decontamination reagent. These … more
Date: January 1, 1985
Creator: Piciulo, P. L. & Adams, J. W.
Partner: UNT Libraries Government Documents Department
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Variation of stability constants of thorium citrate complexes and of thorium hydrolysis constants with ionic strength

Description: Citrate is among the organic anions that are expected to be present in the wastes planned for deposition in the Waste Isolation Pilot Plant repository. In this study, a solvent extraction method has been used to measure the stability constants of Thorium(IV)[Th(IV)] with citrate anions in aqueous solutions with (a) NaClO{sub 4} and (b) NaCl as the background electrolytes. The ionic strengths were varied up to 5 m (NaCl) and 14 m (NaClO{sub 4}). The data from the NaClO{sub 4} solutions at varyin… more
Date: September 1, 1995
Creator: Choppin, Gregory R.; Erten, Hasan N. & Xia, Yuan-Xian
Partner: UNT Libraries Government Documents Department
open access

Bioremediation of Uranium Contaminated Soils and Wastes.

Description: Contamination of soils, water, and sediments by radionuclides and toxic metals from uranium mill tailings, nuclear fuel manufacturing and nuclear weapons production is a major concern. Studies of the mechanisms of biotransformation of uranium and toxic metals under various microbial process conditions has resulted in the development of two treatment processes: (i) stabilization of uranium and toxic metals with reduction in waste volume and (ii) removal and recovery of uranium and toxic metals f… more
Date: September 17, 1998
Creator: Francis, A. J.
Partner: UNT Libraries Government Documents Department
open access

Microbial Transformations of Uranium and Environmental Restoration Through Bioremediation.

Description: Microorganisms present in the natural environment play a significant role in the mobilization and immobilization of uranium. Fundamental understanding of the mechanisms of microbiological transformations of various chemical forms of uranium present in wastes and contaminated soils and water has led to the development of novel bioremediation processes. One process uses anaerobic bacteria to stabilize the radionuclides and toxic metals from the waste, with a concurrent reduction in volume due to … more
Date: September 10, 2002
Creator: Francis, A. J.
Partner: UNT Libraries Government Documents Department
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