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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 19 of 19 for “"sulfurization"”.
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Evaluating redox cycling across the Toarcian Oceanic Anoxic Event with implications for paleo-environmental reconstructions and organic matter sulfurization
… the occurrence and extent of organic matter sulfurization (OMS), a biogeochemical feedback known to enhance the preservation and burial of OM. Because this process is accelerated when euxinic conditions develop in the water column, I investigated it as a mechanism promoting OM burial across …
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Organic Sulfur-Bearing Species as Subsurface Carbon Storage Vectors
… for permanent subsurface sequestration. Natural sulfurization processes in sedimentary organic matter are investigated as mechanisms to generate biologically refractory water-soluble organic molecules. Such molecular vectors could be sequestered in shallow, saline, contaminated aquifers through …
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A biogeochemical investigation of Trunk River Lagoon, Falmouth, Massachusetts
… sewage. Moreover, lipid analyses reveals rapid sulfurization of organic matter in the water column. In Chapter 4, attention turns to the preservation of biolipids within modern microbial mats. Through detailed analysis, the study reveals primary diagenetic processes such as hydrogenation and …
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Purity matters : enhancing carrier transport properties in tin sulfide for photovoltaic applications by reducing impurity content
… properties of SnS. High-purity SnS is grown via sulfurization of tin films, and compared with baseline material made from feedstock with two orders of magnitude higher impurity content. Minority-carrier lifetime, morphology, and impurity content are analyzed in both materials. It is shown that …
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Preparation of oriented molybdenum disulfide thin films for photoelectrochemical energy havesting applications
… films of MoS2 from chemical exfoliation and sulfurization of evaporated MoOx. Finally, I will discuss the issues and challenges of photoelectrochemical measurements.
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Processing and Optical Uses of Van der Waals Layered Materials
… We identify opposite roles of oxygen during the sulfurization process as a reaction catalyst or an inhibitor, for MoS₂ and TiS₂ formation respectively. In MoS₂, O₂ promotes the crystallization of MoS₂ at lower temperature (as low as 400 °C). On the other hand, the kinetic barrier of replacing …
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Developing transition metal dichalcogenide alloys for applications to integrated photonics
… method of metal film deposition, followed by sulfurization in an H₂S gas furnace. We demonstrate different roughening processes for each case and optimize the morphology.
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Preparation And Characterization Of Cigss Solar Cells And Pv Module Data Analysis
… for better uniformity. Further, selenization/ sulfurization of these precursors was carried out using rapid thermal processing (RTP). CIGS films were sulfurized using chemical bath deposition (CBD). ZnO:Al was deposited on the CIGSS films using RF sputtering. A separate LABVIEW program was …
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Emerging electronic materials : thin films of asphaltenes and coal nanoparticles for electronic devices and large area layer controlled 2-dimensional semiconductor synthesis
… present a divergent growth method for MoS 2 via sulfurization of oxide deposited by both thermal ALD from (tBuN) 2 (NMe2 )2 Mo and O3 and plasma enhanced ALD (PEALD) from (tBuN)2 (NMe2 )2Mo and remote O2 plasma. Large uniform MoS 2 areas were achieved by studying the effects of various growth …
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Biofuels production from hydrotreating of vegetable oil using supported noble metals, and transition metal carbide and nitride
… resources under a lower pressure without sulfurization reagents involved in the process. NiMoC/Al-SBA-15 showed the greatest potential for producing green diesel from renewable feedstock.</p>
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Unravelling the impacts of palaeoecology, palaeoenvironment and lithofacies on sedimentary organic NSO compounds
… of polyfunctionalized biomolecules via sulfurization, such as C40 carotenoids, C35 bacteriohopanepolyols, C30 unsaturated tetracyclic polyprenoid alcohols, C30 or C25 highly branched isoprenoid (HBI) polyenes. The strong enrichment of sulfurized C35 bacteriohopanepolyols can be developed …
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Developing high efficiency Cu2ZnSnS4 (CZTS) thin film solar cells by sputtering
… solar cell efficiency. Secondly, the effects of sulfurization annealing atmosphere and post-heat treatment have been studied. The “epitaxial” CdS/CZTS interface and moderate Cd diffusion effects were discovered, found to play critical roles in improving the cell efficiency. Thirdly, the …
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Characterization Of Microstructural And Chemical Features In Cu-in-ga-se-s-based Thin-film Solar Cells
… deposits, residual Se from the selenization/ sulfurization chamber in CIGS2 and the formation of Cu-rich regions which are attributed to decomposition effects in the Ga beam of the FIB. Wavy absorber surfaces were observed for some of the cells with occasional discontinuities in the metal …
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Solar Driven Photoelectrochemical Water Splitting For Hydrogen Generation Using Multiple Bandgap Tandem Of Cigs2 Pv Cells And Thin Film Photocatalyst
… new world record for CIGS2 cells developed using sulfurization and the open circuit voltage of 830.5 mV has become the "Voc champion value". New PEC setups with the RuS2 and Ru0.99Fe0.01S2 photoanodes were developed. RuS2 and Ru0.99Fe0.01S2 photoanodes were more stable in the electrolyte and …
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Electron Transfer Processes between Hydrogen Sulfide and Humic Substances - Implications for Anaerobic Sulfur Cycling in Freshwater Ecosystems
… organic matter as proposed earlier, but also a sulfurization of OM yielding reduced organic sulfur, and changes in oxidized organic sulfur species. In conclusion, our results quantitatively demonstrated both HA and reduced HA can abiotically re-oxidize sulfide in anoxic environments at rates …
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Elucidation of the Various Mechanisms of Antioxidant Activity of Organosulfur Compounds
Polysulfides, produced from olefin sulfurization, are common additives to various petroleum-derived products such as engine oils, hydraulic fluids, rubbers and polymeric materials in an effort to protect these materials from oxidative degradation. The mechanisms by which organosulfur compounds act …
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Characterization of industrially processed chalcopyrite solar cells with varied absorber composition
In the present thesis by publication loss mechanisms in industrially processed chalcopyrite thin film solar cells of the conventional ZnO:Al/i-ZnO/CdS/Cu(In,Ga)(Se,S)2/Mo layer structure investigated. The results of this thesis were obtained within two independent projects with different industry …
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Geochemical tools and paleoclimate clues : multi-molecular and isotopic investigations of tropical marine sediments and alpine ice
… compounds argue against significant sulfurization and resultant biomarker sequestration in 1228D sediments. Factor analysis provided a statistical means of separating terrestrial and marine organic inputs, and reinforced the interpretations that very long chain n-alkanoic acids …
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Solution-Processed Thin Film Deposition and Characterization of Multinary Chalcogenides: Towards Highly Efficient Cu2BaSn(S,Se)4 Solar Devices
… solvent DMSO, followed by spin coating, sulfurization and selenization steps at high temperatures. The ball milling approach, on the other hand, involves dispersion of ball-milled Cu2S, BaS, Sn, and S particles in low-toxicity ethanol, followed by sulfur and selenium treatments at high …