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INNOVATIVE INSTRUMENTATION AND ANALYSIS OF THE TEMPERATURE MEASUREMENT FOR HIGH TEMPERATURE GASIFICATION

Description: The systematic tests of the gasifier simulator on the ultrasonic vibration application for cleaning method were completed in this reporting period. Within the systematic tests on the ultrasonic vibration application, the ambient temperature and high temperature status condition were tested separately. The sticky dirt on the thermocouple tip was simulated by the cement-covered layer on the thermocouple tip. At the ambient temperature status, four (4) factors were considered as the input factors affecting the response variable of peeling off rate. The input factors include the shape of the cement-covered layer (thickness and length), the ultrasonic vibration output power, and application time. At the high temperature tests, four (4) different environments were considered as the experimental parameters including air flow supply, water and air supply environment, water/air/fine dust particle supply, and air/water/ammonia/fine dust particle supply environment. The factorial design method was used in the experiment design with twelve (12) data sets of readings. Analysis of Variances (ANOVA) was applied to the results from systematic tests. The ANOVA results show that the thickness and length of the cement-covered layer have the significant impact on the peeling off rate of ultrasonic vibration application at the ambient temperature environment. For the high temperature tests, the different environments do not seem to have significant impact on the temperature changes. These results may indicate that the ultrasonic vibration is one of best cleaning methods for the thermocouple tip.
Date: April 1, 2005
Creator: Lee, Seong W.
Partner: UNT Libraries Government Documents Department
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A NOVEL MEMBRANE REACTOR FOR DIRECT HYDROGEN PRODUCTION FROM COAL

Description: Gas Technology Institute is developing a novel concept of membrane reactor coupled with a gasifier for high efficiency, clean and low cost production of hydrogen from coal. The concept incorporates a hydrogen-selective membrane within a gasification reactor for direct extraction of hydrogen from coal-derived synthesis gases. The objective of this project is to determine the technical and economic feasibility of this concept by screening, testing and identifying potential candidate membranes under high temperature, high pressure, and harsh environments of the coal gasification conditions. The best performing membranes will be selected for preliminary reactor design and cost estimates. To evaluate the performances of the candidate membranes under the gasification conditions, a high temperature/high pressure hydrogen permeation unit has been constructed in this project. The unit is designed to operate at temperatures up to 1100 C and pressures to 60 atm for evaluation of ceramic membranes such as mixed protonic-electronic conducting membrane. Several perovskite membranes based on the formulations of BCN (BaCe{sub 0.8}Nd{sub 0.2}O{sub 3-x}), BCY (BaCe{sub 0.8}Y{sub 0.2}O{sub 3-x}), Eu-doped SrCeO{sub 3} (SCE) and SrCe{sub 0.95}Tm{sub 0.05}O{sub 3} (SCTm) were successfully tested in the new permeation unit. During this reporting period, a thin BCN membrane supported on a porous BCN layer was fabricated. The objective was to increase the hydrogen flux with a further reduction of the thickness of the active membrane layer. The thinnest dense layer that could be achieved in our laboratory currently was about 0.2 mm. Nevertheless, the membrane was tested in the permeation unit and showed reasonable flux compared to the previous BCN samples of the same thickness. A long term durability test was conducted for a SCTm membrane with pure hydrogen in the feed side and nitrogen in the sweep side. The pressure was 1 bar and the temperature was around 1010 C. No decline of …
Date: April 28, 2005
Creator: Doong, Shain; Ong, Estela; Atroshenko, Mike; Lau, Francis & Roberts, Mike
Partner: UNT Libraries Government Documents Department
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AN INTEGRATED MULTI-COMPONENT PROCESSING AND INTERPRETATION FRAMEWORK FOR 3D BOREHOLE SEISMIC DATA

Description: This report covers the November 2004-March 2005 time period. A mid year project review meeting was held at DOE facilities on November 30th. Work has been performed successfully on several tasks 3 through 15. Most of these tasks have been executed independently. We progressed steadily and completed some of the sub-tasks, while others are still on going. We achieved the goals that we had set up in the task schedule. Reviewing the results of this work period indicates that our plan is solid and we did not encounter any unforeseen problems. The work plan will continue as projected.
Date: April 15, 2005
Creator: Karrenbach, M.
Partner: UNT Libraries Government Documents Department
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Fundamentals of Reservoir Surface Energy as Related to Surface Properties, Wettability, Capillary Action, and Oil Recovery From Fractured Reservoirs by Spontaneous Imbibition Quarterly Report

Description: The objective of this project is to increase oil recovery from fractured reservoirs through improved fundamental understanding of the process of spontaneous imbibition by which oil is displaced from the rock matrix into the fractures. Spontaneous imbibition is fundamentally dependent on the reservoir surface free energy but this has never been investigated for rocks. In this project, the surface free energy of rocks will be determined by using liquids that can be solidified within the rock pore space at selected saturations. Thin sections of the rock then provide a two-dimensional view of the rock minerals and the occupant phases. Saturations and oil/rock, water/rock, and oil/water surface areas will be determined by advanced petrographic analysis and the surface free energy which drives spontaneous imbibition will be determined as a function of increase in wetting phase saturation. The inherent loss in surface free energy resulting from capillary instabilities at the microscopic (pore level) scale will be distinguished from the decrease in surface free energy that drives spontaneous imbibition. A mathematical network/numerical model will be developed and tested against experimental results of recovery versus time over broad variation of key factors such as rock properties, fluid phase viscosities, sample size, shape and boundary conditions. Two fundamentally important, but not previously considered, parameters of spontaneous imbibition, the capillary pressure acting to oppose production of oil at the outflow face and the pressure in the nonwetting phase at the no-flow boundary versus time, will also be measured and modeled. Simulation and network models will also be tested against special case solutions provided by analytic models. In the second stage of the project, application of the fundamental concepts developed in the first stage of the project will be demonstrated. The fundamental ideas, measurements, and analytic/numerical modeling will be applied to mixed-wet rocks. Imbibition measurements will include …
Date: April 1, 2005
Creator: Morrow, Norman R.; Fischer, Herbert; Li, Yu; Mason, Geoffrey; Ruth, Douglas; Seth, Siddhartha et al.
Partner: UNT Libraries Government Documents Department
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MINERAL-SURFACTANT INTERACTIONS FOR MINIMUM REAGENTS PRECIPITATION AND ADSORPTION FOR IMPROVED OIL RECOVERY

Description: The aim of this project is to delineate the role of mineralogy of reservoir rocks in determining interactions between reservoir minerals and externally added reagents (surfactants/polymers) and its effect on critical solid-liquid and liquid-liquid interfacial properties such as adsorption, wettability and interfacial tension in systems relevant to reservoir conditions. Previous studies have suggested that significant surfactant loss by precipitation or adsorption on reservoir minerals can cause chemical schemes to be less than satisfactory for enhanced oil recovery. Both macroscopic adsorption, wettability and microscopic orientation and conformation studies for various surfactant/polymer mixtures/reservoir rocks systems were conducted to explore the cause of chemical loss by means of precipitation or adsorption, and the effect of rock mineralogy on the chemical loss. During this period, the adsorption of mixed system of n-dodecyl-{beta}-D-maltoside (DM) and dodecyl sulfonate (C{sub 12}SO{sub 3}Na) has been studied. The effects of solution pH, surfactant mixing ratio and different salts on surfactant adsorption on alumina have been investigated in detail. Along with these adsorption studies, changes in mineral wettability due to the adsorption of the mixtures were determined under relevant conditions to identify the nano-structure of the adsorbed layers. Solution properties of C{sub 12}SO{sub 3}Na/DM mixtures were also studied to identify surfactant interactions that affect the mixed aggregate formation in solution. Adsorption of SDS on gypsum and limestone suggested stronger surfactant/mineral interaction than on alumina, due to the precipitation of surfactant by dissolved calcium ions. The effects of different salts such as sodium nitrate, sodium sulfite and sodium chloride on DM adsorption on alumina have also been determined. As surfactant hemimicelles at interface and micelles in solution have drastic effects on oil recovery processes, their microstructures in solutions and at mineral/solution interfaces were investigated by monitoring micropolarity of the aggregates using fluorescence technique. Compositional changes of the aggregates in solution were …
Date: April 30, 2005
Creator: Somasundaran, P.
Partner: UNT Libraries Government Documents Department
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Analysis of Devonian Black Shales in Kentucky for Potential Carbon Dioxide Sequestration and Enhanced Natural Gas Production Quarterly Report: January-March 2005

Description: Devonian gas shales underlie approximately two-thirds of Kentucky. In the shale, natural gas is adsorbed on clay and kerogen surfaces. This is analogous to methane storage in coal beds, where CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. Drill cuttings from the Kentucky Geological Survey Well Sample and Core Library were sampled to determine CO{sub 2} and CH{sub 4} adsorption isotherms. Sidewall core samples were acquired to investigate CO{sub 2} displacement of methane. An elemental capture spectroscopy log was acquired to investigate possible correlations between adsorption capacity and mineralogy. Average random vitrinite reflectance data range from 0.78 to 1.59 (upper oil to wet gas and condensate hydrocarbon maturity range). Total organic content determined from acid-washed samples ranges from 0.69 to 14 percent. CO{sub 2} adsorption capacities at 400 psi range from a low of 14 scf/ton in less organic-rich zones to more than 136 scf/ton. There is a direct correlation between measured total organic carbon content and the adsorptive capacity of the shale; CO{sub 2} adsorption capacity increases with increasing organic carbon content. Initial estimates based on these data indicate a sequestration capacity of 5.3 billion tons of CO{sub 2} in the Lower Huron Member of the Ohio Shale of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker parts of the Devonian shales in Kentucky. Should the black shales of Kentucky prove to be a viable geologic sink for CO{sub 2}, their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO{sub 2} storage and enhanced natural gas production.
Date: April 26, 2005
Creator: Nuttall, Brandon C.
Partner: UNT Libraries Government Documents Department
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DEVELOPMENT OF PERMANENT MECHANICAL REPAIR SLEEVE FOR PLASTIC PIPE

Description: The report presents a comprehensive summary of the prototype development process utilized towards the development of a permanent mechanical repair fitting intended to be installed on damaged PE mains under blowing gas conditions. Specifically, the step by step construction approach is presented and the experimental data to support the mitigation of ensuing slow crack growth (SCG) of the damage area.
Date: April 29, 2005
Creator: Patadia, Hitesh
Partner: UNT Libraries Government Documents Department
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Spent Nuclear Fuel: Research Needs

Description: In 2005, the global inventory of spent nuclear fuel (SNF) is approximately 175,000 metric tonnes (slightly less than one third is in the USA) (Ewing, 2004). Most of this SNF is still at 236 nuclear power stations where it was originally generated in 36 different countries. In the USA, the inventory in 2010 will be 61,800 metric tonnes of heavy metal (tHM) with a total activity of 32.6 GCi. The USA presently has an open nuclear fuel cycle (without reprocessing) with ultimate disposal at the proposed geologic repository at Yucca Mountain. The SNF represents >95% of the radioactivity. Thus, a major challenge of successful geologic disposal of radioactive waste is to understand the long-term behavior of SNF. SNF is essentially UO{sub 2} with minor impurities, mainly the fission product (3%) and transuranium elements (1%). The precise radionuclide inventory and physical state of the fuel depend on its irradiation and thermal history. Three critical parameters change dramatically during the first 10,000 years in the repository: (1) the thermal output will decrease to < 0.1%; (2) the radioactivity will decrease to < 0.01%; (3) the inventory of radiotoxic nuclides will change. Beyond 10,000 years radionuclides of major importance under oxidizing conditions include: {sup 239}Pu, {sup 237}Np, {sup 129}I and {sup 99}Tc. Less problematic elements include: {sup 241}Am, {sup 79}Se and {sup 36}Cl. These elements exist in a variety of chemical forms: incorporated into the UO{sub 2} structure, as separate phases in inclusions and at grain boundaries. Corrosion under oxidizing conditions leads to the formation of a variety of U(VI)-phases. An understanding of their long-term behavior requires an improved knowledge of their structures, thermochemical parameters, solubilities, substitution mechanisms for trace radionuclides, surface properties and the kinetics of dissolution/precipitation reactions. Natural uranium deposits, such as the Oklo natural reactors, also provide important data. This …
Date: April 20, 2005
Creator: Ewing, R.C.
Partner: UNT Libraries Government Documents Department
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Plasma Shape Control on the National Spherical Torus Experiment (NSTX) using Real-time Equilibrium Reconstruction

Description: Plasma shape control using real-time equilibrium reconstruction has been implemented on the National Spherical Torus Experiment (NSTX). The rtEFIT code originally developed for use on DIII-D was adapted for use on NSTX. The real-time equilibria provide calculations of the flux at points on the plasma boundary, which is used as input to a shape control algorithm known as isoflux control. The flux at the desired boundary location is compared to a reference flux value, and this flux error is used as the basic feedback quantity for the poloidal-field coils on NSTX. The hardware that comprises the control system is described, as well as the software infrastructure. Examples of precise boundary control are also presented.
Date: April 15, 2005
Creator: Gates, D. A.; Ferron, J. R.; Bell, M.; Gibney, T.; Johnson, R.; Marsala, R. J. et al.
Partner: UNT Libraries Government Documents Department
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NERSC Annual Report 2004

Description: The National Energy Research Scientific Computing Center (NERSC) is the premier computational resource for scientific research funded by the DOE Office of Science. The Annual Report includes summaries of recent significant and representative computational science projects conducted on NERSC systems as well as information about NERSC's current and planned systems and services.
Date: April 15, 2005
Creator: Hules, John; Bashor, Jon; Yarris, Lynn; McCullough, Julie; Preuss, Paul & Bethel, Wes
Partner: UNT Libraries Government Documents Department
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The Fundamental Role of Nano-Scale Oxide Films in the Oxidation of Hydrogen and the Reduction of Oxygen on Noble Metal Electrocatalysts: Final Report

Description: The derivation of successful fuel cell technologies requires the development of more effective, cheaper, and poison-resistant electrocatalysts for both the anode (H{sub 2} oxidation in the presence of small amounts of CO from the reforming of carbonaceous fuels) and the cathode (reduction of oxygen in the presence of carried-over fuel). The proposed work is tightly focused on one specific aspect of electrocatalysis; the fundamental role(s) played by nanoscale (1-2 nm thick) oxide (''passive'') films that form on the electrocatalyst surfaces above substrate-dependent, critical potentials, on charge transfer reactions, particularly at elevated temperatures (25 C < T < 200 C). Once the role(s) of these films is (are) adequately understood, we will then use this information to specify, at the molecular level, optimal properties of the passive layer for the efficient electrocatalysis of the oxygen reduction reaction.
Date: April 15, 2005
Creator: Macdonald, Digby
Partner: UNT Libraries Government Documents Department
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A Rgularized Boltzmann Scattering Operator for Highly Forward Peaked Scattering

Description: Extremely short collision mean free paths and near-singular elastic and inelastic differential cross sections (DCS) make analog Monte Carlo and deterministic computational approaches impractical for charged particle transport. The widely used alternative, the condensed history method, while efficient, also suffers from several limitations arising from the use of precomputed infinite medium distributions for sampling particle directions and energies.
Date: April 13, 2005
Creator: Prinja, Anil K.
Partner: UNT Libraries Government Documents Department
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Computational Platform for Flux Analysis Using 13C-Label Tracing- Phase I SBIR Final Report

Description: Isotopic label tracing is a powerful experimental technique that can be combined with metabolic models to quantify metabolic fluxes in an organism under a particular set of growth conditions. In this work we constructed a genome-scale metabolic model of Methylobacterium extorquens, a facultative methylotroph with potential application in the production of useful chemicals from methanol. A series of labeling experiments were performed using 13C-methanol, and the resulting distribution of labeled carbon in the proteinogenic amino acids was determined by mass spectrometry. Algorithms were developed to analyze this data in context of the metabolic model, yielding flux distributions for wild-type and several engineered strains of M. extorquens. These fluxes were compared to those predicted by model simulation alone, and also integrated with microarray data to give an improved understanding of the metabolic physiology of this organism.
Date: April 12, 2005
Creator: Van Dien, Stephen J.
Partner: UNT Libraries Government Documents Department
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Renewable Energy RFPs: Solicitation Response and Wind ContractPrices

Description: As input into renewable energy policy discussions in Illinois, we have been asked to provide information on the results of recent, competitive solicitations for renewable energy, with a focus on wind power. In particular, this memorandum includes two pieces of information: (1) Publicly available data on the strength of response to recent renewable energy solicitations; and (2) Wind power purchase costs as revealed through actual power purchase agreements with electric utilities.
Date: April 18, 2005
Creator: Wiser, Ryan & Bolinger, Mark
Partner: UNT Libraries Government Documents Department
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On the Transition from Thermally-driven to Ponderomotively-driven Stimulated Brillouin Scattering and Filamentation of Light in Plasma

Description: The dispersion properties of ion acoustic waves and their nonlinear coupling to light waves through ponderomotive and thermal forces are sensitive to the strength of electron-ion collisions. Here, we consider the growth rate of stimulated Brillouin scattering (SBS) when the driven acoustic wave frequency and wavelength span the range of small to large compared to electron-ion collision frequency and mean free path respectively. We find in all cases the thermal contributions to the SBS growth rate are insignificant if the ion acoustic wave frequency is greater than the electron-ion collision frequency and the wavelength is much shorter than the electron-ion mean free path. On the other hand, the purely growing filamentation instability remains thermally driven for shorter wavelengths than SBS even when the growth rate is larger than the acoustic frequency.
Date: April 4, 2005
Creator: Berger, R. L.; Valeo, E. J. & Brunner, S.
Partner: UNT Libraries Government Documents Department
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ADVANCED SOLID STATE SENSORS FOR VISION 21 SYSTEMS

Description: Silicon carbide (SiC) is a high temperature semiconductor with the potential to meet the gas and temperature sensor needs in both present and future power generation systems. These devices have been and are currently being investigated for a variety of high temperature sensing applications. These include leak detection, fire detection, environmental control, and emissions monitoring. Electronically these sensors can be very simple Schottky diode structures that rely on gas-induced changes in electrical characteristics at the metal-semiconductor interface. In these devices, thermal stability of the interfaces has been shown to be an essential requirement for improving and maintaining sensor sensitivity and lifetime. In this report, we describe device fabrication and characterization studies relevant to the development of SiC based gas and temperature sensors. Specifically, we have investigated the use of periodically stepped surfaces to improve the thermal stability of the metal semiconductor interface for simple Pd-SiC Schottky diodes. These periodically stepped surfaces have atomically flat terraces on the order of 200 nm wide separated by steps of 1.5 nm height. It should be noted that 1.5 nm is the unit cell height for the 6H-SiC (0001) substrates used in these studies. These surfaces contrast markedly with the ''standard'' SiC surfaces normally used in device fabrication. Obvious scratches and pots as well as subsurface defects characterize these standard surfaces. This research involved ultrahigh vacuum deposition and characterization studies to investigate the thermal stability of Pd-SiC Schottky diodes on both the stepped and standard surfaces, high temperature electrical characterization of these device structures, and high temperature electrical characterization of diodes under wet and dry oxidizing conditions. To our knowledge, these studies have yielded the first electrical characterization of actual sensor device structures fabricated under ultrahigh vacuum conditions. The results demonstrate that the Pd-SiC interfaces formed on the stepped surface are remarkably stable at …
Date: April 28, 2005
Creator: Stinespring, C.D.
Partner: UNT Libraries Government Documents Department
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Canister Handling Facility Description Document

Description: The purpose of this facility description document (FDD) is to establish requirements and associated bases that drive the design of the Canister Handling Facility (CHF), which will allow the design effort to proceed to license application. This FDD will be revised at strategic points as the design matures. This FDD identifies the requirements and describes the facility design, as it currently exists, with emphasis on attributes of the design provided to meet the requirements. This FDD is an engineering tool for design control; accordingly, the primary audience and users are design engineers. This FDD is part of an iterative design process. It leads the design process with regard to the flowdown of upper tier requirements onto the facility. Knowledge of these requirements is essential in performing the design process. The FDD follows the design with regard to the description of the facility. The description provided in this FDD reflects the current results of the design process.
Date: April 21, 2005
Creator: Beesley, J. F.
Partner: UNT Libraries Government Documents Department
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Observation of Persistent Edge Current Driven by Coaxial Helicity Injection (CHI)

Description: Coaxial Helicity Injection, CHI, has been used on the National Spherical Torus Experiment (NSTX) [M. Ono et al., Nucl. Fusion 40 (2000) 557], the Helicity Injected Torus (HIT) [B.A. Nelson et al., Phys. Rev. Lett. 72 (1994) 3666] and HIT-II [T.R. Jarboe et al., Phys. Plasmas 5 (1998) 1807] to initiate plasma and to drive up to 400 kA of toroidal current. On HIT-II, CHI initiated discharges have been successfully coupled to ohmic sustainment [R. Raman et al., Phys. Plasmas 11 (2004) 2565]. This paper presents the first results on the use of CHI to demonstrate the persistence of edge current drive in a preestablished single-null diverted inductive discharge. Edge current drive has the potential to improve plasma stability limits [J.E. Menard et al., Nucl. Fusion 37 (1997) 595]. While most current drive methods drive current in the interior of the plasma, CHI is well suited for driving current in the edge plasma.
Date: April 21, 2005
Creator: Mueller, D.; Nelson, B. A.; Hamp, W. T.; Redd, A. J.; Jarboe, T. R.; O'Neill, R. G. et al.
Partner: UNT Libraries Government Documents Department
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Refractory for Black Liquor Gasifiers Quarterly Report

Description: The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective surfaces in-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided …
Date: April 1, 2005
Creator: Jr, William L. Headrick; Karakus, Musa; Liang, Xiaoting & Wei, Jun
Partner: UNT Libraries Government Documents Department
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Fundamentals of Melt-Water Interfacial Transport Phenomena: Improved Understanding for Innovative Safety Technologies in ALWRs

Description: The interaction and mixing of high-temperature melt and water is the important technical issue in the safety assessment of water-cooled reactors to achieve ultimate core coolability. For specific advanced light water reactor (ALWR) designs, deliberate mixing of the core-melt and water is being considered as a mitigative measure, to assure ex-vessel core coolability. The goal of this work is to provide the fundamental understanding needed for melt-water interfacial transport phenomena, thus enabling the development of innovative safety technologies for advanced LWRs that will assure ex-vessel core coolability. The work considers the ex-vessel coolability phenomena in two stages. The first stage is the melt quenching process and is being addressed by Argonne National Lab and University of Wisconsin in modified test facilities. Given a quenched melt in the form of solidified debris, the second stage is to characterize the long-term debris cooling process and is being addressed by Korean Maritime University in via test and analyses. We then address the appropriate scaling and design methodologies for reactor applications.
Date: April 26, 2005
Creator: Anderson, M.; Corradini, M.; Bank, K.Y.; Bonazza, R. & Cho, D.
Partner: UNT Libraries Government Documents Department
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Top physics: measurement of the cross section for ttbar production in ppbar collisions using the kinematics of lepton + jets events

Description: We present a measurement of the top pair production cross section in p{bar p} collisions at {radical}s = 1.96 TeV. We collect a data sample with an integrated luminosity of 194 {+-} 11 pb{sup -1} with the CDF II detector at the Fermilab Tevatron. We use an artificial neural network technique to discriminate between top pair production and background processes in a sample of 519 lepton+jets events, which have one isolated energetic charged lepton, large missing transverse energy and at least three energetic jets. We measure the top pair production cross section to be {sigma}{sub t{bar t}} = 6.6 {+-} 1.1 {+-} 1.5 pb, where the first uncertainty is statistical and the second is systematic.
Date: April 27, 2005
Creator: Acosta, D.
Partner: UNT Libraries Government Documents Department
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Advanced Technologies for Stripper Gas Well Enhancement

Description: This report summarizes a quarterly report of the advanced technologies for stripper gas well enhancement during July 1 to September 30, 2004.
Date: April 27, 2005
Creator: MacDonald, Ronald J.
Partner: UNT Libraries Government Documents Department
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