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The Use of Electrochemical Techniques to Characterize Wet Steam Environments

Description: The composition of a steam phase in equilibrium with a water phase at high temperature is remarkably affected by the varying capabilities of the water phase constituents to partition into the steam. Ionic impurities (sodium, chloride, sulfate, etc.) tend to remain in the water phase, while weakly ionic or gaseous species (oxygen) partition into the steam. Analysis of the water phase can provide misleading results concerning the steam phase composition or environment. This paper describes efforts that were made to use novel electrochemical probes and sampling techniques to directly characterize a wet steam phase environment in equilibrium with high temperature water. Probes were designed to make electrochemical measurements in the thin film of water existing on exposed surfaces in steam over a water phase. Some of these probes were referenced against a conventional high temperature electrode located in the water phase. Others used two different materials (typically tungsten and platinum) to make measurements without a true reference electrode. The novel probes were also deployed in a steam space removed from the water phase. It was necessary to construct a reservoir and an external, air-cooled condenser to automatically keep the reservoir full of condensed steam. Conventional reference and working electrodes were placed in the water phase of the reservoir and the novel probes protruded into the vapor space above it. Finally, water phase probes (both reference and working electrodes) were added to the hot condensed steam in the external condenser. Since the condensing action collapsed the volatiles back into the water phase, these electrodes proved to be extremely sensitive at detecting oxygen, which is one of the species of highest concern in high temperature power systems. Although the novel steam phase probes provided encouraging initial results, the tendency for tungsten to completely corrode away in the steam phase limited their usefulness. …
Date: April 30, 2003
Creator: Bussert, Bruce W.; Crowley, John A.; Kimball, Kenneth J. & Lashway, Brian J.
Partner: UNT Libraries Government Documents Department
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Testing V-A in top decay at CDF at squareroot s = 1.8 TeV

Description: The structure of the tbW vertex can be probed by measuring the polarization of the W in t {yields} W + b {yields} l + v + b. The invariant mass of the lepton and b quark measures the W decay angle which in turn allows a comparison with polarizations expected from a V-A and V+A tbW vertex. We measure the fraction by rate of Ws produced with a V+A coupling in lieu of the Standard Model V-A to be f{sub V+A} = -0.21{sub -0.24}{sup +0.42}(stat) {+-} 0.21(sys). We assign a limit of f{sub V+A} < 0.80 {at} 95% CL. By combining this result with a complementary observable in the same data, we assign a limit of f{sub V+A} < 0.61 {at} 95% CL. From this CDF Run I preliminary result, we find no evidence for a non-standard Model tbW vertex.
Date: September 30, 2003
Creator: Kilminster, B.
Partner: UNT Libraries Government Documents Department
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Preparations for EUV interferometry of the 0.3 NA MET optic

Description: An at-wavelength interferometer is being created for the measurement and alignment of the 0.3 numerical aperture Micro Exposure Tool projection optic at EUV wavelengths. The prototype MET system promises to provide early learning from EUV lithographic imaging down to 20-nm feature size. The threefold increase to 0.3 NA in the image-side numerical aperture presents several challenges for the extension of ultra-high-accuracy interferometry, including pinhole fabrication and the calibration and removal of systematic error sources.
Date: October 30, 2003
Creator: Goldberg, Kenneth A.; Naulleau, Patrick P.; Denham, Paul E.; Rekawa, Senajith B.; Jackson, Keith H.; Liddle, J. Alexander et al.
Partner: UNT Libraries Government Documents Department
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Final Technical/Scientific Report: Commodity Scale Thermostable Enzymatic Transformations

Description: The conversion of corn starch to high fructose corn-syrup sweetener is a commodity process, producing over 3 billion kg/y. In the last step of the process, an enzyme catalyst is used to convert glucose to the much sweeter sugar fructose. Due to incomplete conversion in the last step, the syrup must be purified using a chromatographic separation technique, which results in equal quantities of water being added to the syrup, and finally the water must be evaporated (up to 1 lb of water/lb of syrup). We have estimated the energy requirement in the evaporation step to be on the order of 13 billion BTU's/y. This process inefficiency could be eliminated if a thermostable form of glucose isomerase (GI), the enzyme catalyst used in the final step, was developed. Our chosen strategy was to develop an immobilized form of the enzyme in which the protein is first crystallized and then chemically cross-linked to form an insoluble particle. This so-called cross-linked enzyme crystal (CLE C(reg. sign)) technology had been shown to be a powerful method for enzyme stabilization for several other protein catalysts. In this work we have developed more than 30 CLEC preparations of glucose isomerase and tested them for activity and stability. We found these preparations to be highly active, with a 10-50 fold rate per gram of catalyst increase over existing commercial catalysts. The initial rates were also higher at higher temperatures as expected, however the efficiency of the CLEC GI preparations unexpectedly rapidly decreased to a low constant value with use at the higher temperatures. At this point, the source of this activity loss is unclear, however during this loss, the catalyst is found to form a solid mass indicating either breakage of the chemical cross-links or simple aggregation of the particles. It is likely that the increased …
Date: August 30, 2003
Creator: Lalonde, James J. & Davison, Brian
Partner: UNT Libraries Government Documents Department
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Photoinduced nucleation: a new technology for the detection of chemical contaminants. Final Report

Description: This research grant supported the creation and initial development of a new kind of chemical detector; one that can detect species at part per trillion levels because it does not rely on the direct measurement of a species presence; rather, it uses an indirect measurement of the effect of the trace species on the condensation nucleation of a supersaturated vapor. Since this nucleation process is extremely sensitive to the concentrations of certain types of impurities, this nucleation-based detection can be made more sensitive than any current spectroscopic detector.
Date: September 30, 2003
Creator: Katz, Joseph L.
Partner: UNT Libraries Government Documents Department
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Chemical stockpile emergency preparedness program (CSEPP) recovery plan workbook.

Description: The Recovery Plan Workbook is designed for use by U.S. Army chemical installations and state and local authorities who participate in the Chemical Stockpile Emergency Preparedness Program (CSEPP). The workbook includes a model recovery plan that provides a template for preparation of an integrated CSEPP recovery plan. The workbook also provides background, explanatory, and reference materials to aid planners. The model plan provides a general example and framework for planning but is not complete without input from the local CSEPP community. Each chemical stockpile location has site-specific needs, resources, and organizational differences that will shape recovery planning. Therefore, the purpose of the model plan, in part, is to raise questions that installation, state, and local planners will have to answer to develop a site-specific recovery plan. It is recommended that a single, overarching recovery plan be developed to coordinate the activities of the installation, state, and local jurisdictions at a given site. As stated in Planning Guidance for the CSEPP, Appendix M, ''The reentry/restoration plan should be integrated and coordinated among the Army installation and other state and local jurisdictions in the IRZ and PAZ.'' The integrated approach is more efficient from a planning perspective (compared to separate, parallel plans for each jurisdiction) and will facilitate coordination among the organizations. To be effective, many aspects of recovery must also be coordinated. For example, if several jurisdictions submit competing requests to the Army for monitoring services, confusion might result, and some important monitoring activities might be delayed. A coordinated plan would ensure that monitoring is conducted in proper order of priority. A single integrated recovery plan can be designed to accommodate the decision-making prerogatives of all included organizations. Jurisdiction-specific annexes may be appropriate in some cases to accommodate the unique needs of particular jurisdictions.
Date: July 30, 2003
Creator: Lerner, K.; Yantosik, G.; Vasco, M.B. & Motz, L.
Partner: UNT Libraries Government Documents Department
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Advanced Sorbents as a Versatile Platform for Gas Separation

Description: The program objective was to develop materials and processes for industrial gas separations to reduce energy use and enable waste reduction. The approach chosen combined novel oxygen selective adsorbents and pressure swing adsorption (PSA) processes. Preliminary materials development and process simulation results indicated that oxygen selective adsorbents could provide a versatile platform for industrial gas separations. If fully successful, this new technology offered the potential for reducing the cost of producing nitrogen/oxygen co-products, high purity nitrogen, argon, and possibly oxygen. The potential energy savings for the gas separations are appreciable, but the end users are the main beneficiaries. Lowering the cost of industrial gases expands their use in applications that can employ them for reducing energy consumption and emissions.
Date: September 30, 2003
Creator: Stephenson, Neil
Partner: UNT Libraries Government Documents Department
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Sorption Modeling of Strontium, Plutonium, Uranium and Neptunium Adsorption on Monosodium Titanate

Description: We examined the ability of various equilibrium isotherms to replicate the available data for the adsorption of strontium (Sr), plutonium (Pu), uranium (U) and neptunium (Np) on monosodium titanate (MST) during the treatment of simulated and actual Savannah River Site high-level waste. The analysis considered 29 isotherm models from the literature. As part of this study, we developed a general method for selecting the best isotherm models. The selection criteria for rating the isotherms considered the relative error in predicting the experimental data, the complexity of the mathematical expressions, the thermodynamic validity of the expressions, and statistical significance for the expressions. The Fowler Guggenheim-Jovanovic Freundlich (FG-JF), the Fowler Guggenheim-Langmuir Freundlich (FG-LF) and the Dubinin-Astashov (DA) models each reliably predicted the actinide and strontium adsorption on MST. The first two models describe the adsorption process by single layer formation and later al interactions between adsorbed sorbates while the Dubinin-Astashov model assumes volume filling of micropores (by osmotic pressure difference). These two mechanisms include mutually exclusive assumptions. However, we can not determine which model best represents the various adsorption mechanisms on MST. Based on our analysis, the DA model predicted the data well. The DA model assumes that an initial sorption layer forms after which networking begins in the pore spaces, filling the volume by a second mechanism. If this mechanism occurs in MST, as the experimental data suggests, then we expect all the empty and closed spaces of MST to contain actinides and strontium when saturated. Prior microstructure analyses determined that the MST surface is best described as heterogeneous (i.e., a semi-crystalline outer layer on an amorphous core) or composite material for adsorption. Therefore, we expect the empty spaces (of nanometer size) between the crystalline units in the fibrous material to provide sorption area for the actinides and strontium. Since each …
Date: October 30, 2003
Creator: Fondeur, F. F.
Partner: UNT Libraries Government Documents Department
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Probability of Liquefaction for Pit Disassembly and Conversion Facility (PDCF) Site, Savannah River Site

Description: This report documents the probability of liquefaction (POL) for the Pit Disassembly and Conversion Facility (PDCF). The procedure for analysis of a critical layer of interest requires the following basic steps: (1) establish the probability of occurrence (POO) of ranges of 2.5 Hz bedrock motion based on a probabilistic seismic hazard assessment (PSHA); (2) define the critical layer that may be susceptible to liquefaction; (3) estimate distributions of cyclic stress ratio (CSR) (i.e., seismic demand) for the critical layer using site-specific soil properties corresponding to the bedrock motions; (4) estimate capacity of the critical layer based on site-specific cone penetration test (CPT) soundings and standard penetration test (SPT) blowcount data; and (5) sum the probability of liquefaction for each range of bedrock motion using empirical data correlating demand and capacity with liquefaction. The soil layer most susceptible to liquefaction is the critical layer. The critical layer is characterized by relatively low blowcount and low fines content and is established from soil layers below the water table. A key component for seismic demand is the establishment of the soil profile and it's uncertainty. The PDCF site is consistent with the 1997 SRS-specific model used to compute the site amplification database. Thus, previously derived site amplification functions reflecting the uncertainty in site properties and stratigraphy can be used to predict distributions of CSR given a specific earthquake magnitude and level of bedrock motion. The previously developed site amplification database reflects uncertainty in site response based on the large database of site shear-wave velocity profiles. Consequently, for each level of bedrock motion (from the PSHA) the site amplification database is used to establish the distribution of the expected CSR (demand) in the critical layer.
Date: September 30, 2003
Creator: Lee, R.C.
Partner: UNT Libraries Government Documents Department
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Ventilation technologies scoping study

Description: This document presents the findings of a scoping study commissioned by the Public Interest Energy Research (PIER) program of the California Energy Commission to determine what research is necessary to develop new residential ventilation requirements for California. This study is one of three companion efforts needed to complete the job of determining the needs of California, determining residential ventilation requirements, and determining appropriate ventilation technologies to meet these needs and requirements in an energy efficient manner. Rather than providing research results, this scoping study identifies important research questions along with the level of effort necessary to address these questions and the costs, risks, and benefits of pursuing alternative research questions. In approaching these questions and level of effort, feasibility and timing were important considerations. The Commission has specified Summer 2005 as the latest date for completing this research in time to update the 2008 version of California's Energy Code (Title 24).
Date: September 30, 2003
Creator: Walker, Iain S. & Sherman, Max H.
Partner: UNT Libraries Government Documents Department
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Reactive Multiphase Behavior of CO2 in Saline Aquifers Beneath the Colorado Plateau

Description: Gas reservoirs developed within the Colorado Plateau and Southern Rocky Mountains region represent unique natural laboratories for studying the conditions that control long-term storage of CO{sub 2}. Under appropriate conditions, the trapping of CO{sub 2} in mineral phases could equal or exceed the amount of CO{sub 2} sequestered in the pore fluids in deep aquifers. Core samples from the Springerville-St. Johns CO{sub 2} field has allowed investigation of naturally occurring mineral reactions. The presence of travertine deposits over the field provide evidence of the leakage of CO{sub 2} to the atmosphere and justify further study. During reporting period covered here (January 1 to March 30, 2003), the main achievements were: (1) Preparation of three papers to be presented at the Second Annual Conference on Carbon Sequestion (May 5-8, Alexandria, Virginia) and (2) Preparation of two papers for submission to a special volume of Chemical Geology on CO{sub 2} Sequestration.
Date: January 30, 2003
Creator: Allis, R. G.; Moore, J. & White, S.
Partner: UNT Libraries Government Documents Department
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Bioenergy Crop Breeding and Production Research in the Southeast, Final Report for 1996 to 2001

Description: Switchgrass (Panicum virgatum L.) is a native grass species to much of the US. It has shown great potential for use in production of fuel ethanol from cellulosic biomass (Lynd et al., 1991). Work in Alabama demonstrated very high dry matter yields can be achieved with switchgrass (Maposse et al. 1995) in the southeastern US. Therefore, this region is thought to be an excellent choice for development of a switchgrass cropping system where farmers can produce the grass for either biomass or forage. Another report has shown success with selection and breeding to develop high yielding germplasm from adapted cultivars and ecotypes of switchgrass (Moser and Vogel 1995). In the mid 1990s, however, there was little plant breeding effort for switchgrass with a potential for developing a cultivar for the southeast region. The main goal of the project was to develop adaptive, high-yielding switchgrass cultivars for use in cropping systems for bioenergy production in the southeastern US. A secondary objective was to assess the potential of alternate herbaceous species such as bermudagrass (Cynodon dactylon L.), bahiagrass (Paspalum notatum Flugge.), and napiergrass (Pennisetum purpureum Schumach.) that may compete with switchgrass for herbaceous bioenergy production in the southeast. During the conduct of the project, another goal of developing molecular markers useful for genetic mapping was added. The ''lowland'' cultivars, Alamo and Kanlow, were found to be the highest yielding switchgrass cultivars. Although most summers during the project period were hot and dry, their annual dry matter yield continue to outperform the best ''upland'' cultivars such as Cave-in-Rock, Shawnee, NE Late, and Trailblazer. The use of a breeding procedure based on the ''honeycomb design'' and multi-location progeny testing, coupled with the solid heritability and genetic gain estimates for dry matter yield in lowland type switchgrass germplasm, indicated excellent potential to isolate parental genotypes …
Date: May 30, 2003
Creator: Bouton, J. H.
Partner: UNT Libraries Government Documents Department
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Evaluate Factors Limiting Columbia River Gorge Chum Salmon Populations; FY 2002 Annual Report.

Description: Adult and juvenile chum salmon were monitored from October 2001 through September 2002 to evaluate factors limiting production. In 2001, 6 and 69 adult chum salmon were captured in the Hardy Creek and Hamilton Springs weirs, respectively. In 2001, 285 and 328 chum salmon carcasses were recovered during spawning ground surveys in Hardy Creek and Hamilton Springs, respectively. Twenty-eight fish captured in the mainstem Columbia River, Hamilton Springs, and Hardy Creek were implanted with radio tags and tracked via an array of fixed aerial, underwater antennas and a mobile tracking unit. Using the Area-Under-the-Curve program population estimates of adult chum salmon were 835 in Hardy Creek and 617 in Hamilton Springs. Juvenile chum salmon migration was monitored from March-June 2002. Total catches for Hardy Creek and Hamilton Springs were 103,315 and 140,220, respectively. Estimates of juvenile chum salmon emigration were 450,195 ({+-}21,793) in Hardy Creek and 561,462 ({+-}21,423) in Hamilton Springs.
Date: January 30, 2003
Creator: Uusitalo, Nancy M.
Partner: UNT Libraries Government Documents Department
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Improved Miscible Nitrogen Flood Performance Utilizing Advanced Reservoir Characterization and Horizontal Laterals in a Class I Reservoir - East Binger (Marchand) Unit Quarterly Report

Description: Implementation of the work program of Budget Period 2 of the East Binger Unit (''EBU'') DOE Project continues. Significant advances with the reservoir simulation model have led to changes in the program. One planned horizontal well location, EBU 44-3H, has been eliminated from the program, and another, EBU 45-3H, has been deferred, and may be replaced by a vertical well or completely eliminated at a future date. A new horizontal well location, EBU 63-2H, has been added. EBU 74G-2, the one new injection well planned for the project, was completed and brought on production. It will be produced for a period of time before converting it to injection. Performance is exceeding expectations. Work also continued on projects aimed at increasing injection in the pilot area. EBU 65-1 was converted to injection service. The project to add compression and increase injection capacity at the nitrogen management facility is nearing completion. Additional producer-to-injector conversions will follow.
Date: May 30, 2003
Creator: Sinner, Joe
Partner: UNT Libraries Government Documents Department
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ASPEN Plus Simulation of CO2 Recovery Process

Description: ASPEN Plus simulations have been created for a CO{sub 2} capture process based on adsorption by monoethanolamine (MEA). Three separate simulations were developed, one each for the flue gas scrubbing, recovery, and purification sections of the process. Although intended to work together, each simulation can be used and executed independently. The simulations were designed as template simulations to be added as a component to other more complex simulations. Applications involving simple cycle or hybrid power production processes were targeted. The default block parameters were developed based on a feed stream of raw flue gas of approximately 14 volume percent CO{sub 2} with a 90% recovery of the CO{sub 2} as liquid. This report presents detailed descriptions of the process sections as well as technical documentation for the ASPEN simulations including the design basis, models employed, key assumptions, design parameters, convergence algorithms, and calculated outputs.
Date: September 30, 2003
Creator: White, Charles W., III
Partner: UNT Libraries Government Documents Department
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Parallel performance of the XL Fortran random{_}number intrinsic function on Seaborg

Description: The Fortran intrinsic function random{_}number is shown to perform very poorly when simultaneously called from 16 tasks per node on NERSC's IBM SP Seaborg in its default runtime configuration. Setting the runtime option intrinthds=16 improves runtime performance significantly and gives good results for all possible numbers of tasks per node. It is speculated that the cause of the problem is the creation of an excessive number of threads in the default configuration. It is noted that these threads appear to be created by default, without specifying a ''thread-safe'' compiler or other user interaction.
Date: July 30, 2003
Creator: Gerber, Richard A.
Partner: UNT Libraries Government Documents Department
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ADVANCED CUTTINGS TRANSPORT STUDY

Description: This is the second quarterly progress report for Year-4 of the ACTS Project. It includes a review of progress made in: (1) Flow Loop construction and development and (2) research tasks during the period of time between October 1, 2002 and December 30, 2002. This report presents a review of progress on the following specific tasks. (a) Design and development of an Advanced Cuttings Transport Facility Task 3: Addition of a Cuttings Injection/Separation System, Task 4: Addition of a Pipe Rotation System. (b) New research project (Task 9b): ''Development of a Foam Generator/Viscometer for Elevated Pressure and Elevated Temperature (EPET) Conditions''. (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions''. (e) Research on three instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), Foam texture while transporting cuttings. (Task 12), and Viscosity of Foam under EPET (Task 9b). (f) New Research project (Task 13): ''Study of Cuttings Transport with Foam under Elevated Pressure and Temperature Conditions''. (g) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S). (h) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.
Date: January 30, 2003
Creator: Reed, Troy; Miska, Stefan; Takach, Nicholas; Ashenayi, Kaveh; Pickell, Mark; Volk, Len et al.
Partner: UNT Libraries Government Documents Department
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STEADY STATE FLAMMABLE GAS RELEASE RATE CALCULATION & LOWER FLAMMABILITY LEVEL EVALUATION FOR HANFORD TANK WASTE [SEC 1 & 2]

Description: Flammable gases such as hydrogen, ammonia, and methane are observed in the tank dome space of the Hanford Site high-level waste tanks. This report assesses the steady-state flammability level under normal and off-normal ventilation conditions in the tank dome space for 177 double-shell tanks and single-shell tanks at the Hanford Site. The steady-state flammability level was estimated from the gas concentration of the mixture in the dome space using estimated gas release rates, Le Chatelier's rule and lower flammability limits of fuels in an air mixture. A time-dependent equation of gas concentration, which is a function of the gas release and ventilation rates in the dome space, has been developed for both soluble and insoluble gases. With this dynamic model, the time required to reach the specified flammability level at a given ventilation condition can be calculated. In the evaluation, hydrogen generation rates can be calculated for a given tank waste composition and its physical condition (e.g., waste density, waste volume, temperature, etc.) using the empirical rate equation model provided in Empirical Rate Equation Model and Rate Calculations of Hydrogen Generation for Hanford Tank Waste, HNF-3851. The release rate of other insoluble gases and the mass transport properties of the soluble gas can be derived from the observed steady-state gas concentration under normal ventilation conditions. The off-normal ventilation rate is assumed to be natural barometric breathing only. A large body of data is required to do both the hydrogen generation rate calculation and the flammability level evaluation. For tank waste that does not have sample-based data, a statistical-based value from probability distribution regression was used based on data from tanks belonging to a similar waste group. This report (Revision 3) updates the input data of hydrogen generation rates calculation for 177 tanks using the waste composition information in the Best-Basis …
Date: September 30, 2003
Creator: Hu, T. A.
Partner: UNT Libraries Government Documents Department
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A Thermoelastic Hydraulic Fracture Design Tool for Geothermal Reservoir Development

Description: Geothermal energy is recovered by circulating water through heat exchange areas within a hot rock mass. Geothermal reservoir rock masses generally consist of igneous and metamorphic rocks that have low matrix permeability. Therefore, cracks and fractures play a significant role in extraction of geothermal energy by providing the major pathways for fluid flow and heat exchange. Thus, knowledge of conditions leading to formation of fractures and fracture networks is of paramount importance. Furthermore, in the absence of natural fractures or adequate connectivity, artificial fracture are created in the reservoir using hydraulic fracturing. At times, the practice aims to create a number of parallel fractures connecting a pair of wells. Multiple fractures are preferred because of the large size necessary when using only a single fracture. Although the basic idea is rather simple, hydraulic fracturing is a complex process involving interactions of high pressure fluid injections with a stressed hot rock mass, mechanical interaction of induced fractures with existing natural fractures, and the spatial and temporal variations of in-situ stress. As a result it is necessary to develop tools that can be used to study these interactions as an integral part of a comprehensive approach to geothermal reservoir development, particularly enhanced geothermal systems. In response to this need we have set out to develop advanced thermo-mechanical models for design of artificial fractures and rock fracture research in geothermal reservoirs. These models consider the significant hydraulic and thermo-mechanical processes and their interaction with the in-situ stress state. Wellbore failure and fracture initiation is studied using a model that fully couples poro-mechanical and thermo-mechanical effects. The fracture propagation model is based on a complex variable and regular displacement discontinuity formulations. In the complex variable approach the displacement discontinuities are defined from the numerical solution of a complex hypersingular integral equation written for a …
Date: June 30, 2003
Creator: Ghassemi, Ahmad
Partner: UNT Libraries Government Documents Department
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Examples of cooler reflective streets for urban heat-island mitigation : Portland cement concrete and chip seals

Description: Part of the urban heat island effect can be attributed to dark pavements that are commonly used on streets and parking lots. In this paper we consider two light colored, hence cooler, alternative paving materials that are in actual use in cities today. These are Portland cement concrete (PCC) pavements and chip seals. We report measurements of the albedos of some PCC and chip sealed pavements in the San Francisco Bay Area. The albedos of the PCC pavements ranged from about 0.18 to 0.35. The temperatures of some PCC pavements are also measured and calculated. We then consider how the albedos of the constituent materials of the PCC (stone, sand and cement) contribute to the albedos of the resulting finished concrete. The albedos of a set of chip sealed pavements in San Jose, CA, were measured and correlated with the times of their placement. It is found that the albedos decrease with age (and use) but remain higher than that of standard asphalt concrete (AC) for about five years. After t hat, the albedos of the chip seals are about 0.12, similar to aged AC. The fact that many PCC pavements have albedos at least twice as high as aged AC suggests that it is possible to have pavement albedos that remain high for many years.
Date: April 30, 2003
Creator: Pomerantz, M.; Akbari, H.; Chang, S. C.; Levinson, R. & Pon, B.
Partner: UNT Libraries Government Documents Department
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Rotary Burner Demonstration

Description: The subject technology, the Calcpos Rotary Burner (CRB), is a burner that is proposed to reduce energy consumption and emission levels in comparison to currently available technology. burners are used throughout industry to produce the heat that is required during the refining process. Refineries seek to minimize the use of energy in refining while still meeting EPA regulations for emissions.
Date: April 30, 2003
Creator: Flanagan, Paul
Partner: UNT Libraries Government Documents Department
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RP-5 RENEWABLE ENERGY PROJECT

Description: This is the second quarterly technical report for the RP-5 Renewable Energy Project. The report summarizes the work progress, effort and activities that took place during the period of October 1, 2002 to December 31, 2002. The report has been prepared in accordance with the Department of Energy (DOE) Guidelines. This technical report covers all meetings and discussions that were conducted in order to follow up on potential renewable energy technologies that were identified in the previous report; the technologies were analyzed for their feasibility, suitability and cost effectiveness for this project. This report covers the one-day conceptual design kickoff meeting that took place on November 4, 2002. The meeting was held to discuss the practicality and implementation of potential innovative technologies. Following the kickoff meeting, Inland Empire Utilities Agency (IEUA) and CH2M Hill, the Public Interest Energy Research (PIER) Consultant, held a meeting on December 2, 2002 to discuss the Conceptual Design Report outline and contents in order to clearly present each selected technology along with its evaluation, cost effectiveness and justification. A conference call also took place between the PIER Consultant and IEUA on December 13, 2002, to discuss the overall scope of work for this project. Major project activities in this period include expanded discussions on previous Energy Charrette decisions and recommendations, conceptual design kickoff meeting, conceptual design report, and deciding on the overall project scope of work.
Date: January 30, 2003
Creator: Clifton, Neil; Whitman, Eliza Jane & Zughbi, Jamal A.
Partner: UNT Libraries Government Documents Department
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DEVELOPMENT OF A VALIDATED MODEL FOR USE IN MINIMIZING NOx EMISSIONS AND MAXIMIZING CARBON UTILIZATION WHEN CO-FIRING BIOMASS WITH COAL

Description: In full-scale boilers, the effect of biomass cofiring on NO{sub x} and unburned carbon (UBC) emissions has been found to be site-specific. Few sets of field data are comparable and no consistent database of information exists upon which cofiring fuel choice or injection system design can be based to assure that NOX emissions will be minimized and UBC be reduced. This report presents the results of a comprehensive project that generated an extensive set of pilot-scale test data that were used to validate a new predictive model for the cofiring of biomass and coal. All testing was performed at the 3.6 MMBtu/hr (1.75 MW{sub t}) Southern Company Services/Southern Research Institute Combustion Research Facility where a variety of burner configurations, coals, biomasses, and biomass injection schemes were utilized to generate a database of consistent, scalable, experimental results (422 separate test conditions). This database was then used to validate a new model for predicting NO{sub x} and UBC emissions from the cofiring of biomass and coal. This model is based on an Advanced Post-Processing (APP) technique that generates an equivalent network of idealized reactor elements from a conventional CFD simulation. The APP reactor network is a computational environment that allows for the incorporation of all relevant chemical reaction mechanisms and provides a new tool to quantify NOx and UBC emissions for any cofired combination of coal and biomass.
Date: April 30, 2003
Creator: Felix, Larry G.; Bush, P. Vann & Niksa, Stephen
Partner: UNT Libraries Government Documents Department
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Measurement of the indium segregation in InGaN based LEDs with single atom sensitivity

Description: In light emitting diodes (LED) consisting of GaN/InGaN/GaN quantum wells (QWs), the exact indium distribution inside the wells of the active region affects the performance of devices. Indium segregation can take place forming small InGaN clusters of locally varying composition. In the past, we used a local strain analysis from single HRTEM lattice images to determine the In composition inside the InGaN QWs with a resolution of 0.5 nm x 0.3 nm. Truly atomic resolution can be pursued by exploitation of intensity dependencies on the atomic number (Z) of the electron exit-wave (EW). In microscopes with sufficient sensitivity, local variations of amplitude and phase are found to be discrete with sample thickness, which allows for counting the number of atoms in each individual column of {approx}0.08 nm diameter. In QW s of {approx}17 percent of average indium concentration it is possible to discriminate between pure Ga columns and columns containing 1, 2, 3, or more In atoms because phase changes are discrete and element specific. The preparation of samples with atomically flat surfaces is a limiting factor for the application of the procedure.
Date: July 30, 2003
Creator: Jinschek, Joerg; Kisielowski, Christian; Van Dyck, Dirk & Geuens, Philippe
Partner: UNT Libraries Government Documents Department
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