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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 20 of 31 for “"Oxide growth"”.
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Oxidation kinetics of 316l stainless steel in the pressurised water reactor environment
… steels, this investigation measured the oxide growth kinetics of 316L stainless steel when exposed to a simulated primary water environment of a pressurised water reactor (PWR). It is generally accepted that intergranular oxidation at the surface of a metal forms a preferential site for …
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Mild wear in dry and lubricated sliding systems
… was found to occur via a thin film logarithmic oxide growth followed by agglomeration into thicker oxide plateaux 2 to 10 m in thickness. Lubricated wear occurred via thick film diffusion controlled oxide growth producing homogeneous oxide plateaux 0.1 to 0.2 m in thickness. X-ray photoelectron …
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OXIDATION OF SILICON CARBIDE AND GRAPHITE FOR HIGH TEMPERATURE GAS-COOLED REACTOR APPLICATIONS
… in the SiO<sub>2</sub> scale. By comparing the oxide layer thickness of TRISO particles oxidized in atmospheres containing 0.2 and 20 kPa O<sub>2</sub>, it was found that the mechanism responsible for oxide growth was different at each pO<sub>2</sub>, with activation energies of 168 and 230 …
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Measurements of electric field noise and light-induced charging in cryogenic surface electrode ion traps
… electrode traps. In addition, the effect of oxide growth on field noise and electrode charging is explored by controlling the thickness of aluminum oxide on several aluminum traps. The measurements show that electric field noise can be suppressed in aluminum traps to approximately 10-18 V2 …
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Optically Powered Logic Transistor
… using CMOS fabrication processes including oxide growth, photolithography, precise plasma or chemical wet etching, diffusion processes, and thin film evaporation. Electrical measurements were done by using an HP4156 parameter analyzer to measure several output voltage signals at one time …
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Interfacial Structures of Oxides on GaAs
For the deposited oxide/GaAs work, only deposition of (Ga,Gd)$\sb2$O$\sb3$ oxide among others shows a low interface trap density (D$\rm\sb{it})$ at the oxide-GaAs interface. It is low enough to warrant the demonstration of both n- and p-channel enhancement GaAs MOSFETs. High-resolution transmission …
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Effectiveness of Thermal Oxidation in Relation to Anterior Cervical Plates
… may damage a section of the protective oxide layer, potentially exposing surrounding tissues to the harmful effects of bare titanium, aluminum, and vanadium. Thermal oxidation has been shown to improve corrosion-resistance and wear-resistance, depending on temperature and time. To …
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Magnetic properties of block-copolymer fabricated cobalt nanodots and nanowires at elevated temperatures
… rearrangement occurring above 200°C The depth of oxide growth on the nanodots was calculated to be 2nm deep on the surface of the nanodots when below 200°Cand no more than 10nm deep when above 200°C Activation volume calculations could not be accurately calculated, suggesting an activation volume …
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Oxidational wear of low alloy steel in gases other than air
… of worn pins and to measure the thickness of the oxide films. Microhardness tests were carried out to investigate the influence of the sub-surface microhardness in tribological conditions. Under all loads, speeds and atmospheres parabolic oxidation growth was observed on worn surfaces, although …
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Titanium dioxide dielectric layers made by anodization of titanium: the effect of dissolved nitrogen and oxygen
… the Ti substrateon the formation of the anodic oxide and its properties, particularly the leakage currentdensity. The best diffusion treatment condition to decrease the leakage current densityfor Grade 1 Ti was found to be infusion at 1133 K (860 °C) for 22 ks. Under this condition, nitrogen and …
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The effect of bond coat oxidation on the microstructure and endurance of two thermal barrier coating systems
… on both coatings. A detailed examination on the oxide thickness was conducted on all specimens, along with characterisation of the bond coat and TGO. This was coupled with examination of specimen cross-sections for cracking and signs of coating degradation. Isothermal oxidation showed sub …
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The Boundary Lubricated Friction and Wear of Low Alloy Steel
… in the lubricant is the controlling factor in oxide growth and wear.
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Innovative fuel designs for high power density pressurized water reactor
… Five issues involving manufacturing tolerances, oxide growth on rod surfaces, inner and outer gap conductances asymmetry, MDNBR sensitivity to changes in core operation parameter and resistance to instabilities were also evaluated.
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Magneto-optical and multiferroic oxide thin films, integrated nonreciprocal photonic devices and multiferroic memory devices
Complex oxide thin films offer unique functionalities which can potentially extend the utility of current storage, processing and optical isolator technologies. In this thesis, we present three categories of studies on complex oxide growth using pulsed laser deposition (PLD) and structural, …
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The effect of surface modification on the crystal growth of iron oxides
The growth of Fe₃O₄ and FeOOH crystals was investigated. Growth modifiers were used to alter the formation of iron oxides from ferrous hydroxide precipitates. Multifunctional carboxylic acids were found to have a strong influence on morphology of FeOOH. Dicarboxylic acids, containing two and seven …
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Ultrasonic and electroplating approach for washcoat of γ-alumina and nickel oxide (nio) catalyst on fecral substrate for catalytic converter
… spalling since the loose adhesion and unstable oxide growth in long term oxidation. Therefore, the main objective of this study are to embed γ-Al2O3 into substrate, to improve thermal stability as well as to improve conversion efficiency of exhaust gas emission. The methods performed in this …
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Mechanisms of fixed contamination of commonly engineered surfaces
… these result in dissolution of the passive oxide layer formed at the metal surface. This increases the level of secondary waste which, in turn, increases the burden of effluent treatment plants. The passivation of steels in HNO3 is complicated by the autocatalytic reduction of HNO3 to …
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Resolving oxidation phenomena in layered semiconductors and scaled heterogeneous integration for low-power electronics
… feedback loops across all stages, from materials growth to device fabrication and quality control. There is a crucial need for characterisation approaches that can resolve both intricate structure-property relations at the atomic layer level and enable intelligent, cost-effective screening at high …
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On the use of high performance annular fuel in PWRs
… resulted in decreased rod worth. Simultaneous oxide growth and crud buildup on the inner cladding of the annular fuel was simulated in a whole core thermal-hydraulics model to determine the maximum thickness that the annular fuel can tolerate while maintaining an MDNBR greater than 1.3 under …
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Corrosion of various engineering alloys in supercritical carbon dioxide
… alloys were tested in a supercritical carbon dioxide (S-CO 2) environment for up to 3000 hours at 610°C and 20MPa. The purpose of this work was to evaluate each alloy as a potential candidate for use in the S-CO2 cooled next generation nuclear reactors. The alloys that performed well in these …
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