Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 17 of 17 for “"Sulfur oxidation"”.
-
Nonstoichiometry of chalcocite in water-xanthate systems
… computer calculations for the copper-sulfur-water system involving different Cu/S ratios that pertain to chalcocite, djurleite, anilite and covellite. Calculations were completed for cases where oxidation of the sulfur proceeded to i) elemental sulfur, ii) thiosulfate, iii) sulfate and …
-
Cloud Chemical Heterogeneity and Its Influence on Aqueous sulfur(IV) Oxidation
… Chemical species including acidity, total sulfur (IV), hydrogen peroxide, formaldehyde, hydroxymethanesulfonate (HMS) and trace metals iron and manganese were measured. Samples were collected with three cloud samplers capable of partitioning the cloud drop size spectrum into two or three …
-
Microbiology of the sulfur-dominated glacial ecosystem at Borup Fiord Pass, and high Arctic low-temperature spring associated microbial mats, The
… a unique low-temperature environment. BFP is a sulfur-dominated ecosystem that occurs within the Krieger mountains. Here, a subglacial spring emergences from the toe of a coalescence glacier. The presence of high concentrations of sulfur and low temperatures make BFP an excellent terrestrial …
-
Investigation of Dibenzothiophene Removal from I Organic Phase: Enzymatic Approach vs. Ionic Liquids
Sulfur in fuel fractions like gasoline and diesel is responsible for acid-rain. The low levels of sulfur in fuels imposed by the environmental regulations of 15 ppm by 2006, have led to the search of alternative methods to comply with these new demands. The conventional process of …
-
The Archean origin of assimilatory sulfate metabolisms provides novel insight into redox conditions of early Earth environments
Dissimilatory sulfur metabolisms recording differing biological isotopic fractionation are well studied, important components of sulfur cycling (Mateos et al., 2023). Assimilatory sulfur metabolisms and genes across life provide a complementary window into sulfur biogeochemistry with individual …
-
Biophysical and Functional Characterization of the Persulfide Sensor CstR from Staphylococcus aureus
… regulate the intracellular bioavailable pool of sulfur while mitigating its toxic effects is poorly understood. Major components of this pool, collectively referred to as reactive sulfur species (RSS), include hydrogen sulfide (H2S) and low molecular weight per- and polysulfides and become …
-
Productivity, metabolism and physiology of free-living chemoautotrophic Epsilonproteobacteria
… redox reactions revealed new insights into sulfur and nitrogen cycling. Single-cell, taxonomically-resolved tracer incorporation showed Epsilonproteobacteria dominated carbon fixation, and their growth efficiency was calculated based on electron acceptor consumption. Using these data, in …
-
Productivity, metabolism and physiology of free-living Chemoautotrophic Epsilonproteobacteria
… redox reactions revealed new insights into sulfur and nitrogen cycling. Single-cell, taxonomically-resolved tracer incorporation showed Epsilonproteobacteria dominated carbon fixation, and their growth efficiency was calculated based on electron acceptor consumption. Using these data, in …
-
Speleogenetic Evolution and Geological Remote Sensing of the Gypsum Plain, Eddy County, New Mexico
… intrastratal brecciation, calcitization and sulfur oxidation.</p> <p>Late Miocene uplift and tilting of the Delaware Basin tectonic block initiated development of dissolution and collapse of Castile strata, inducing an early phase of hypogene karsting. Renewed uplift and tilting during the …
-
Insights into communities, metabolic and ecological potential of the bacteria of two extreme acidic environments
… locationsoriginates from the natural pyrite ore oxidation processes, the sites show a dramaticcontrast in microbial compositions, function, complexity, and diversity. The chemicalcomposition of the sites is suggestive of that of acid mine drainage (AMD) systems;however, the habitats of the Paint …
-
Metal/polymer interactions in polyimide adhesives
… This study examines the effect of thioether sulfur in the polyimide backbone on bond strength. X-ray photoelecton spectroscopy (XPS) and reflectance infrared spectroscopy indicated that certain metals catalyze the oxidation of the thioether sulfur. It was believed that this oxidation could …
-
Understanding The Molecular Mechanism Of Manganese Oxidation In Leptothrix Discophora Ss1
… understand the molecular mechanism of manganese oxidation in Leptothrix discophora SS1 which until now has been hampered by the lack of a genetic system. Leptothrix discophora SS1 is an important model organism that has been used to study the mechanism and consequences of biological manganese …
-
Novel synthetic methodology employing organosulfur chemistry in the synthesis of chalcone derivatives
… synthetic intermediates. They can also undergo sulfur oxidation enabling further functionalisation. The first chapter is a literature review of Stille coupling involving b-haloenone systems, including where this is embedded as a substructure, e.g. in aromatic systems, from 1996 onwards. The …
-
Thermodynamic and kinetic studies of sulfur geochemistry
The thermodynamic properties of aqueous sulfur species were estimated using a structure-based, group contribution additivity method that is based upon first-order approximations. Structural groups were chosen so as to minimize subjectivity and maximize the ease of recognition and include: (1) …
-
Microbial nitrogen-cycling and cooperation in the terrestrial subsurface
… denitrification, anaerobic ammonium oxidation (anammox), and assimilation. The microorganisms that perform these processes can be sources and sinks of nitrate – a major anthropogenic contaminant of aquifers. Therefore, it is crucial that we understand how natural and anthropogenic …
-
A prototype dynamic model for the co-treatment of a high strength simple-organic industrial effluent and coal-mine drainage
… system. The BSR-GL system recovers elemental sulfur (S0 ) from the H2S produced and stripped from the BSR unit. Furthermore, this study aims to use the prototype model for a quantitative comparison of the CSTR-BSR and BSR-GL systems. Two bench-scale 5-litre CSTR-BSR and a 20-litre BSR-GL …
-
Importance of Sulfide, Polysulfides, and Elemental Sulfur for Abiotic and Biotic Redox Processes in Sulfur-Metal(loid)Systems
Sulfur, an ubiquitous element in the environment, occurs in different oxidation states from +6 to -2. Between the thermodynamically stable end members sulfate and sulfide, a variety of intermediate sulfur species exist, examples of which are sulfite, polythionates, thiosulfate, elemental sulfur, …