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Indium Tin Oxide Nanoparticles Formation for Organic ElectronicsYu, Hyeonghwa January 2016 (has links)
Indium tin oxide is a transparent conductive oxide electrode which is widely used for organic electronics. Morphology of ITO plays an important role in the performance of organic electronics. To understand the influence of the substrate morphology in device performance, a controllable route for producing periodic and aperiodic roughness of ITO surfaces are necessary. In this thesis, this was attempted by using various approaches to forming ITO nanostructures. Initially, ITO was deposited by a traditional sputtering procedure. However, the roughness distribution of the sputtered ITO resulted in a s Gaussian distribution, unsuitable to further studies of roughness. ITO nanostructures can also be formed by depositing ITO nanoparticles on an ITO sub- strates. Using acetate and chloride precursors, ITO films were produced from solution and formed into nanoparticles using the reverse micelles deposition approach. The acetate route (InAc+SnCl2+ethanol), was the most successful prior to the nanoparticle formation, showing high quality ITO with bixbyte crystal structure and Sn percentages of 20%, low enough to form a conductive film. Nanoparticles were fabricated with diblock copolymer reverse micelles(PS-b-P2VP). Reverse micelles were found to act as a nano reactor, restricting the size of nanoparticles by having hydrophilic reactants undergo chemical reactions inside the micelles. However, nanoparticles from the reverse micelles revealed Sn percentages much above 20%. This was attributed to the solubility difference of the precursors leading to displacing or preventing of pre- cursor loading into the reverse micelles. The change of the stirring time, the micelles concentration, the sequence of precursors loading, and the weight of precursors were not found to affect the Sn concentration; moreover, large variations in Sn concentrations were observed. From quantitative nano mechanical testing of the micelles, a maximum load amount for the precursors was observed, confirming that the high concentration of Sn was likely due to the solubility differences between the precursors and their ability to penetrate the micelle. By manipulating the nanoparticles distribution through spin coating speeds, micelles concentration, and deposited volume, several degrees of order were obtained, though hexagonal packing was not observed. In general, even though Sn concentration were found to be above 20%, nanoparticles were successfully fabricated with reverse micelles, confirming that the reverse micelle technique is a good strategy for future studies of roughness. / Thesis / Master of Applied Science (MASc)
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Phenolic resin/polyhedral oligomeric silsesquioxane (POSS) hybrid nanocomposites and advanced composites for use as anode materials in lithium ion batteriesLee, Sang Ho 15 December 2007 (has links)
The work presented in this thesis can be divided into two research areas. First, two sets of organic-inorganic hybrid nanocomposites containing phenolic resin/trisilanolphenyl-POSS and phenolic resin/octa(aminophenyl)-T8-POSS nanocomposites were synthesized and the morphology and properties were investigated. Octa(aminophenyl)-T8-polyhedral silsesquioxane is an octafunctional-T8-POSS containing eight aniline-like amino groups, one on each corner silicon atom. It was synthesized in our laboratory by an improved two-step reaction sequence; nitration (HNO3) and reduction (HCOOH/Et3N). Varying amounts of POSS were codissolved with a resole phenolic resin in organic solvent. This was followed by solvent removal and thermal curing. Intermolecular interactions in these nanocomposites were probed by FT-IR. The micro-morphology and aggregation state of POSS were investigated using SEM, TEM, and WAXD studies. The thermal and mechanical properties and thermal stabilities of these composites were investigated by DMTA, DSC, and TGA. Second, two types of carbon-covered mono- and bimetallic (Sn, and Sn/Sb alloy) nanorods for use as anode materials in lithium ion batteries were synthesized by a thermal chemical vapor deposition method. Commercial antimony and tin oxide (Sb3O4/SnO2) nanopowders and added tin (IV) oxide (SnO2) nanoparticles (~19 nm) were used as the precursors for the growth of bimetallic Sn/Sb alloy and monometallic Sn nanorods, respectively. In addition, the shape of the products recovered were different when different hydrocarbon gas flow rates were used for growing intermetallic nanorods in carbon templates. Acetylene and methane were the gases tried. The morphologies and structures of the intermetallic nanorods in carbon templates were investigated using SEM and TEM and proved by X-EDS, XRD, and XPS studies.
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DEVELOPMENT OF SPECTROELECTROCHEMICAL WAVEGUIDE SENSORSRoss, Susan E. January 2000 (has links)
No description available.
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Conducting Polymer Matrix Poly(2,2’-Bithiophene) Mercuric Metal Ion IncorporationKingdom, Rachel Michele 09 December 2009 (has links)
No description available.
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Metal Organic Composites Derived Tin Dioxide/C Nanoparticles For Sodium-Ion BatteryLiang, Wenfeng 10 June 2016 (has links)
No description available.
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Nanostructures by gas-phase reactions: growth and applicationsCarney, Carmen M. 21 November 2006 (has links)
No description available.
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Nb3Sn Targets Synthesis via Liquid Tin Diffusion for Thin Films DepositionsZanierato, Matteo, Azzolini, Oscar, Cavazzani, Jonathan, Chyhyrynets, Eduard, Garcia Diaz, Vanessa, Glisenti, Antonella, Keppel, Giorgio, Ragazzo, Nico, Stivanello, Fabrizio, Pira, Cristian 21 September 2022 (has links)
The deposition of superconducting Nb3 Sn on copper accelerating cavities is interesting for
the higher thermal conductivity of copper compared to common Nb substrates. The better heat
exchange would allow the use of cryocoolers reducing cryogenic costs and the risk of thermal
quench [1]. The magnetron sputtering technology allows the deposition of Nb 3 Sn on substrates
different than Nb, however the coating of substrates with complex geometry (such as elliptical
cavities) may require target with non-planar shape, which are difficult to realize with classic
powder sintering techniques. In this work, the possibility of using the Liquid Tin Diffusion
(LTD) technique to produce sputtering targets is explored. The LTD technique is a wire
fabrication technology, already developed in the past at LNL for superconducting radio
frequency (SRF) applications [2], that allows the deposition of very thick and uniform coating
on Nb substrates even with complex geometries [3]. Improvements in LTD process, proof of
concept of a single use LTD target production, and characterization of the Nb 3 Sn film coated
by DC magnetron sputtering with these innovative targets are reported in this work.
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X-ray analysis of the time-softening property of a lead tin alloyWeaver, Bertha H. January 1941 (has links)
The purpose of this thesis has been the determination of the nature and cause of time-softening property of the lead-tin alloys in the solid solution range. An alloy of 19% tin, 81% lead was chosen as exhibiting the property to a degree suitable for observation of the accompanying phenomena.
The investigation proceeded in three parts: (1) an observation of the time-softening property itself by means of series of hardness tests to determine the degree of change and the time required for its accomplishment; (2) a search for x-ray evidence of possible precipitation which might be apparent as a change in the lattice constant of the crystal; and (3) conductivity measurements as a further check on whether the solution concentration was changing.
The results accordingly may be classified under the same three headings.
The change in hardness of the lead-tin alloy under investigation is intimately related to its habit of precipitating some of the excess tin from the solid solution. Both the x-ray and the conductivity test results offer supporting evidence that precipitation does occur in conjunction with the softening effect.
Apparently also the softening effect observed in the lead-tin alloy is a definite phenomenon distinct from the “over-aging” effect in which an alloy aged at high temperature increases rapidly in hardness until a certain critical hardness is reached, after which softening sets in. / M.S.
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Evaluation of TIN extraction methods for various terrain texturesO'Connor, Mark J. 18 September 2008 (has links)
This study focuses on the Triangulated Irregular Network (TIN) model for representing terrain. A TIN is a vector representation of terrain composed of vertices, lines, and triangular polygons. The elevation values are stored in the vertices. TINs are used in Geographic Information Systems (GIS) for terrain analyses. In particular 1 compare TIN extraction methods. A TIN extraction method is a method in which points are selected from a raster Digital Elevation Model (DEM) in order to construct a TIN. Evaluations of TIN extraction methods have been performed in the past. However, none have compared the TIN extraction methods with terrain texture. This study compared and analyzed the four most popular TIN extraction methods: VIP, Hierarchy, Drop Heuristic, and LATTICETIN. Comparison of the TIN extraction methods was based on the 90th percentile of the absolute error, the absolute error being the absolute difference between TIN elevation and DEM elevation at each point. The results indicated that LATTICETIN yielded the lowest 90th percentile errors for all types of terrain textures and Drop Heuristic was second best in most instances. The Hierarchy method was superior to VIP when less than 12% of the original DEM points were selected. When 12% of the original DEM points were selected, VIP outperformed the Hierarchy method. A correlation was found among TIN accuracy and terrain texture. There was a direct relationship between the two variables. / Master of Science
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Evaluation the performance of the tin (IV) oxide (SnO2) in the removal of sulfur compounds via oxidative-extractive desulfurization process for production an eco-friendly fuelHumadi, J.I., Issa, Y.S., Aqar, D.Y., Ahmed, M.A., Ali Alak, H.H., Mujtaba, Iqbal M. 22 September 2022 (has links)
Yes / Catalysts play a vital role in petroleum and chemical reactions. Intensified concerns for cleaner air with strict environmental regulations on sulfur content in addition to meet economic requirements have generated significant interests for the development of more efficient and innovative oxidative catalysts recently. In this study, a novel homemade nano catalyst (manganese oxide (MnO2) over tin (IV) oxide (SnO2)) was used for the first time as an effective catalyst in removing dibenzothiophene (DBT) from kerosene fuel using hydrogen peroxide (H2O2) as oxidant in catalytic oxidative-extractive desulfurization process (OEDS). The catalyst was prepared by impregnation method with various amount of MnO2 loaded on SnO2. The oxidation step was carried out at different operating parameters such as reaction temperature and reaction time in batch reactor. The extractive desulfurization step was performed by using acetonitrile as solvent under several operating conditions (agitation speed and mixing time). The activity of MnO2/SnO2 catalyst in removing various sulfur compounds from kerosene fuel at the best operating conditions was investigated in this work. The results of the catalyst characterization proved that a high dispersion of MnO2 over the SnO2 was obtained. The experiments showed that the highest DBT and various sulfur compounds removal efficiency from kerosene fuel under the best operating conditions (oxidation: 5% MnO2/SnO2, reaction temperature of 75 0C, and reaction time of 100 min, extraction: acetonitrile, agitation speed of 900 rpm, and mixing time of 30 min) via the catalytic oxidative-extractive desulfurization process was 92.4% and 91.2%, respectively. Also, the MnO2/SnO2 catalyst activity was studied after six consecutive oxidation cycles at the best operating conditions, and the catalyst prove satisfactory stability in terms of sulfur compounds removal. After that, the spent catalyst were regenerated by utilizing different solvents (methanol, ethanol and iso-octane), and the experimental data explained that iso-octane achieved highest regeneration efficiency. / This study was supported by College of Petroleum Processes Engineering, Tikrit University, Iraq and Ministry of Oil, Iraq.
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