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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 56 for “"gas species"”.
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Characterization of Magnetron-Sputtered Partially Ionized Deposition as a Function of Metal and Gas Species
Made available in DSpace on 2017-07-06T18:42:14Z (GMT). No. of bitstreams: 3 Allain_Monica_M_C_MS.pdf: 58019977 bytes, checksum: 4321fbe9df3b2ff27db7a25168c1475e (MD5) Allain_Monica_M_C_MS_ABS.pdf: 548280 bytes, checksum: e229bd5e9fd6338bb6b4380fdd932ba4 (MD5) license.txt: 4813 bytes, checksum: …
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Chemistry models for major gas species estimation and tar prediction in fluidized bed biomass gasification
… deals with the process of fluidized bed biomass gasification (FBBG), which is the thermochemical conversion of solid biomass into combustible synthetic gas using a fluidized bed. Fluidized bed gasifiers encounter high tar concentrations at the gasifier outlet necessitating expensive downstream …
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Reciprocating compressor lubrication – lubricant dilution with natural gas species and the impact on lubrication rates at various operating conditions
… compressors are ubiquitous in the natural gas industry as they provide much of the pressure necessary to move natural gas from the wellhead to the customer. Many of these compressors use lubricants to reduce friction and wear at the piston-cylinder interface. These lubricants have a …
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Radiative Heat Transfer for Emitting, Absorbing and Scattering Planar Media
… predicting the radiative heat transfer in planar gas and particulate systems. The analysis models both nongray absorption of the gas phase by the exponential wide band model and the redirection of radiant energy by particulate scattering through the optical path length concept. The total …
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Characterization and Catalytic Properties of Sulfated Zirconia
… before use. Through on-line analysis of evolved gas species during dynamic heating of the catalysts, some significant information can be obtained concerning the activation mechanism. In the present investigation, combined TG-FTIR, TG-MS and TGDTA techniques were utilized to measure the weight …
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Synthesis, Field Emission and Associated Degradation Mechanisms of Tapered ZnO Nanorods
… degradation mechanisms including, exposure to gas species at high-voltage, and high-current emission.</p> <p>Nanorods of ZnO were grown directly from iron and copper substrates by solution processing, without surface pre-treatment such as seed or catalyst layer. Field emission measurements show …
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Design of a Temperature Programmed Desorption System for the Measurement of the Desorption Kinetics of Molecules from Surfaces
… measuring the partial pressures of the desorbing gas species. It is used to determine the relative coverage and activation energies of the desorbing species. To perform these measurements, a computer controlled feedback control system was designed that generates linear temperature ramps. In …
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Development of A Cascade Adsorption Process For Rapid Xenon Concentration From Air For Nuclear Proliferation Monitoring
… fraction of radioisotopes consisting of noble gases inevitably escape into the atmosphere and can be used to ascertain the occurrence of such detonations. Noble gas Xe radioisotopes, which are produced in large quantities in nuclear events and have relatively long half-lives, are ideal gas …
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Immobilized liquid membranes for facilitated transport and gas separation
Separation and purification of gas mixtures is a major area of activity in chemical engineering. Gas separation using facilitated transport membranes has been the subject of considerable research for many years. Immobilized liquid membranes (ILMs) are an important class of facilitated transport …
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Theoretical and experimental studies of energy transfer dynamics in collisions of atomic and molecular species with model organic surfaces
… of chemical reaction dynamics at the gas/organic-surface interface requires knowledge of energy-transfer processes that happen during the initial gas/surface collision. We have examined the influence of mass and rovibrational motion on the energy-transfer dynamics of gas-phase species …
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Polymer Aluminophosphate Mixed Matrix Membranes for Gas Separations
… polymer matrix decrease the permeability of all gases through that membrane. Our objective was to explore the effects on transport when a microporous layered aluminophosphate was added to a polymer matrix. The clay like layered aluminophosphate used contains sheets with 8MR ring openings in the …
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Identification of metal-organic framework materials for adsorptive separation of the rare gases: applicability of IAST and effects of inaccessible regions
… selective" materials, for which a smaller gas species is preferably adsorbed over a larger species, were explained on the basis of surface fractal geometry, computed via a corrected surface area calculation. The effect of temperature on separation performance was also examined.
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Diagnosis of the flux emanating from the intermediate focus of an extreme ultraviolet light lithography source
… lithography tools, the transport of energetic species that can damage post-intermediate focus optics and increase the cost of tool ownership. In this paper, the effects of chamber pressure, buffer gas mass, and pinch gas mass on debris transport will be explored using the XTREME XTS 13-35 EUV …
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Radical probe system for in-situ measurements of radical densities of hydrogen, oxygen and nitrogen
… methods to identify presence of radical species in vacuum chambers are optical methods, which suffer from the lack of spatial resolution and require expensive optical equipment. In this study Center for Plasma Material Interactions (CPMI) at the University of Illinois developed an in-situ …
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Trace gas imaging in the atmosphere with a Fabry-Pérot interferometer - a case study for sulfur dioxide
Atmospheric trace gas imaging allows the direct assessment of chemical dynamics, transport and mixing processes and is therefore desired in atmospheric physics and chemistry. For instance, the application of imaging measurements at trace gas point sources can substantially improve the determination …
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Electron collisions and internal excitation in stored molecular ion beams
… of collisions with electrons and residual gas species. The low-energy DR of HD+ is rich with resonances from the indirect DR process, when certain initial rotational levels in the molecular ion are coupled to levels in neutral Rydberg states lying below the ion state. Using new procedures …
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Study of particulate matter formation and evolution in near-field aircraft plumes using a one-dimensional microphysical model
… were generated using FLUENT®. The initial gas species concentrations were estimated based on a two-step constrained equilibrium process. Parametric studies of the effects of ambient temperature, ambient relative humidity, engine operating conditions and engine design parameters on the …
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Experimental determination of the volumetric properties for the system CO₂-CH₄-N₂ at 100-1000 bars and 50-300°C
… earth; therefore, thermochemical data on these gas species and their mixtures find application in geochemical modeling of crustal fluids in a wide variety of geologic environments. However, volumetric data for gaseous mixtures are scarce, particularly at high pressures and temperatures. In this …
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CO2 reduction over noble metal/carbon nanotube catalyst
… (CH_4 + CO_2 -> 2CO + 2H_2) and reverse water gas shift (RWGS) (H2 + CO_2 -> CO + H_2O). Reaction temperatures range from 773 to 973 K, with system pressure at 30 psig. The feed molar ratios CH4/CO_2 and CO_2/H_2 are varied from 0.5 to 2.0. Reactant conversions in DR and RWGS are strongly …
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Optical Pumping of Dye Lasers Using an Array of Plasma Pinches
… a few torrs of hydrogen, deuterium or nitrogen gas. A dye cuvette is inserted along the symmetry axis of the plasma device such that it may be surrounded by the plasma pinch. Control of the plasma fluorescence is achieved by the choice of gas, its fill pressure, and the capacitor bank voltage …
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