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Government Activities to Protect the Electric Grid (open access)

Government Activities to Protect the Electric Grid

This report provides a description of initiatives within the Federal Energy Regulatory Commission and the Departments of Energy, Homeland Security, and Defense to protect the physical transmission infrastructure.
Date: October 20, 2004
Creator: Abel, Amy
System: The UNT Digital Library
Government Activities to Protect the Electric Grid (open access)

Government Activities to Protect the Electric Grid

This report provides a description of initiatives within the Federal Energy Regulatory Commission and the Departments of Energy, Homeland Security, and Defense to protect the physical transmission infrastructure.
Date: December 20, 2004
Creator: Abel, Amy
System: The UNT Digital Library
Search for b0(s) --> mu+ mu- and b0(d) --> mu+ mu- decays in p anti-p collisions at s**(1/2) = 1.96 tev (open access)

Search for b0(s) --> mu+ mu- and b0(d) --> mu+ mu- decays in p anti-p collisions at s**(1/2) = 1.96 tev

The authors report on a search for B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -} and B{sub d}{sup 0} {yields} {mu}{sup +}{mu}{sup -} decays in p{bar p} collisions at {radical}s = 1.96 TeV using 171 pb{sup -1} of data collected by the CDF II experiment at the Fermilab Tevatron Collider. The decay rates of these rare processes are sensitive to contributions from physics beyond the Standard Model. One event survives all the selection requirements, consistent with the background expectation. They derive branching ratio limits of {Beta}(B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -}) < 5.8 x 10{sup -7} and {Beta}(B{sub d}{sup 0} {yields} {mu}{sup +}{mu}{sup -}) < 1.5 x 10{sup -7} at 90% confidence level.
Date: March 20, 2004
Creator: Acosta, D.
System: The UNT Digital Library
Design, Construction, and Operation of a Laboratory Scale Reactorfor the Production of High-Purity, Isotopically Enriched Bulksilicon (open access)

Design, Construction, and Operation of a Laboratory Scale Reactorfor the Production of High-Purity, Isotopically Enriched Bulksilicon

The design and operation of a recirculating flow reactor designed to convert isotopically enriched silane to polycrystalline Si with high efficiency and chemical purity is described. The starting material is SiF{sub 4}, which is enriched in the desired isotope by a centrifuge method and subsequently converted to silane. In the reactor, the silane is decomposed to silicon on the surface of a graphite starter rod (3 mm diameter) heated to 700-750 C. Flow and gas composition (0.3-0.5% silane in hydrogen) are chosen to minimize the generation of particles by homogeneous nucleation of silane and to attain uniform deposition along the length of the rod. Growth rates are 5 {micro}m/min, and the conversion efficiency is greater than 95%. A typical run produces 35 gm of polycrystalline Si deposited along a 150 mm length of the rod. After removal of the starter rod, dislocation-free single crystals are formed by the floating zone method. Crystals enriched in all 3 stable isotopes of Si have been made: {sup 28}Si (99.92%), {sup 29}Si (91.37%), and {sup 30}Si (88.25%). Concentrations of electrically active impurities (P and B) are as low as mid-10{sup 13} cm{sup -3}. Concentrations of C and O lie below 10{sup 16} and 10{sup …
Date: December 20, 2004
Creator: Ager, J. W., III; Beeman, J. W.; Hansen, W. L. & Haller, E. E.
System: The UNT Digital Library
Small Column Ion Exchange Analysis for Removal of Cesium from SRS Low Curie Salt Solutions Using Crystalline Silicotitanate (CST) Resin (open access)

Small Column Ion Exchange Analysis for Removal of Cesium from SRS Low Curie Salt Solutions Using Crystalline Silicotitanate (CST) Resin

Savannah River Technology Center (SRTC) researchers modeled ion exchange removal of cesium from dissolved salt waste solutions. The results assist in evaluating proposed configurations for an ion exchange process to remove residual cesium from low curie waste streams. A process for polishing (i.e., removing small amounts) of cesium may prove useful should supernate draining fail to meet the Low Curie Salt (LCS) target limit of 0.1 Ci of Cs-137 per gallon of salt solution. Cesium loading isotherms and column breakthrough curves for Low Curie dissolved salt solutions were computed to provide performance predictions for various column designs.
Date: April 20, 2004
Creator: Aleman, Sebastian E. & Hamm, L. L.
System: The UNT Digital Library
Guide to Individuals Seated on the Senate Dais (open access)

Guide to Individuals Seated on the Senate Dais

This report briefly discusses where various individuals are seated in the Senate chamber.
Date: October 20, 2004
Creator: Amer, Mildred
System: The UNT Digital Library
Membership of the 109th Congress: A Profile (open access)

Membership of the 109th Congress: A Profile

None
Date: December 20, 2004
Creator: Amer, Mildred L.
System: The UNT Digital Library
European Views and Policies Toward the Middle East (open access)

European Views and Policies Toward the Middle East

None
Date: January 20, 2004
Creator: Archick, Kristin
System: The UNT Digital Library
ASSESSMENT OF GENOTOXIC ACTIVITY OF PETROLEUM HYDROCARBON-BIOREMEDIATED SOIL (open access)

ASSESSMENT OF GENOTOXIC ACTIVITY OF PETROLEUM HYDROCARBON-BIOREMEDIATED SOIL

The relationship between toxicity and soil contamination must be understood to develop reliable indicators of environmental restoration for bioremediation. Two bacterial rapid bioassays: SOS chromotest and umu-test with and without metabolic activation (S-9 mixture) were used to evaluate genotoxicity of petroleum hydrocarbon-contaminated soil following bioremediation treatment. The soil was taken from an engineered biopile at the Czor Polish oil refinery. The bioremediation process in the biopile lasted 4 years, and the toxicity measurements were done after this treatment. Carcinogens detected in the soil, polyaromatic hydrocarbons (PAHs), were reduced to low concentrations (2 mg/kg dry wt) by the bioremediation process. Genotoxicity was not observed for soils tested with and without metabolic activation by a liver homogenate (S-9 mixture). However, umu-test was more sensitive than SOS-chromotest in the analysis of petroleum hydrocarbon-bioremediated soil. Analytical results of soil used in the bioassays confirmed that the bioremediation process reduced 81 percent of the petroleum hydrocarbons including PAHs. We conclude that the combined test systems employed in this study are useful tools for the genotoxic examination of remediated petroleum hydrocarbon-contaminated soil.
Date: October 20, 2004
Creator: BRIGMON, ROBIN
System: The UNT Digital Library
High Efficiency Amorphous and Microcrystalline Silicon Based Double-Junction Solar Cells made with Very-High-Frequency Glow Discharge (open access)

High Efficiency Amorphous and Microcrystalline Silicon Based Double-Junction Solar Cells made with Very-High-Frequency Glow Discharge

We have achieved a total-area initial efficiency of 11.47% (active-area efficiency of 12.33%) on a-Si:H/μc-Si:H double-junction structure, where the intrinsic layer bottom cell was made in 50 minutes. On another device in which the bottom cell was made in 30 min, we achieved initial total-area efficiency of 10.58% (active-efficiency of 11.35%). We have shown that the phenomenon of ambient degradation of both μc-Si:H single-junction and a-Si:H/μc-Si:H double-junction cells can be attributed to impurity diffusion after deposition. Optimization of the plasma parameters led to alleviation of the ambient degradation. Appropriate current matching between the top and bottom component cells has resulted in a stable total-area efficiency of 9.7% (active-area efficiency of 10.42%) on an a-Si:H/μc-Si:H double-junction solar cell in which the deposition time for the μc-Si:H intrinsic layer deposition was of 30 min.
Date: October 20, 2004
Creator: Banerjee, Arindam
System: The UNT Digital Library
Integrated Design and Production Reference Integration with ArchGenXML V1.00 (open access)

Integrated Design and Production Reference Integration with ArchGenXML V1.00

ArchGenXML is a tool that allows easy creation of Zope products through the use of Archetypes. The Integrated Design and Production Reference (IDPR) should be highly configurable in order to meet the needs of a diverse engineering community. Ease of configuration is key to the success of IDPR. The purpose of this paper is to describe a method of using a UML diagram editor to configure IDPR through ArchGenXML and Archetypes.
Date: July 20, 2004
Creator: Barter, R H
System: The UNT Digital Library
Defense Cleanup and Environmental Programs: Authorization and Appropriations for FY2005 (open access)

Defense Cleanup and Environmental Programs: Authorization and Appropriations for FY2005

This report provides background information on each defense-related environmental program, discusses key funding issues, and examines relevant provisions in authorization legislation and appropriations for FY2005.
Date: December 20, 2004
Creator: Bearden, David M.
System: The UNT Digital Library
Iraq:  U.S. Military Operations and Costs (open access)

Iraq: U.S. Military Operations and Costs

Iraq’s chemical, biological, and nuclear weapons programs, together with Iraqi long-range missile development and support for al-Queda terrorism, were the primary justifications put forward for military action. On March 17, 2003, President Bush issued an ultimatum demanding that Saddam Hussein and his sons depart from Iraq within 48 hours. On March 19, offensive operations began with air strikes against Iraqi leadership positions. By April 15, after 27 days of operations, coalition forces were in relative control of all major Iraqi cities and Iraqi political and military leadership had disintegrated. On May 1, 2003, President Bush declared an end to major combat operations. There was no use of chemical or biological (CB)weapons, and no CB or nuclear weapons stockpiles or production facilities have been found.
Date: November 20, 2004
Creator: Bowman, Steven R.
System: The UNT Digital Library
Molecular environmental science : an assessment of research accomplishments, available synchrotron radiation facilities, and needs. (open access)

Molecular environmental science : an assessment of research accomplishments, available synchrotron radiation facilities, and needs.

Synchrotron-based techniques are fundamental to research in ''Molecular Environmental Science'' (MES), an emerging field that involves molecular-level studies of chemical and biological processes affecting the speciation, properties, and behavior of contaminants, pollutants, and nutrients in the ecosphere. These techniques enable the study of aqueous solute complexes, poorly crystalline materials, solid-liquid interfaces, mineral-aqueous solution interactions, microbial biofilm-heavy metal interactions, heavy metal-plant interactions, complex material microstructures, and nanomaterials, all of which are important components or processes in the environment. Basic understanding of environmental materials and processes at the molecular scale is essential for risk assessment and management, and reduction of environmental pollutants at field, landscape, and global scales. One of the main purposes of this report is to illustrate the role of synchrotron radiation (SR)-based studies in environmental science and related fields and their impact on environmental problems of importance to society. A major driving force for MES research is the need to characterize, treat, and/or dispose of vast quantities of contaminated materials, including groundwater, sediments, and soils, and to process wastes, at an estimated cost exceeding 150 billion dollars through 2070. A major component of this problem derives from high-level nuclear waste. Other significant components come from mining and industrial wastes, …
Date: October 20, 2004
Creator: Brown, G. E., Jr.; Sutton, S. R.; Bargar, J. R.; Shuh, D. K.; Fenter, P. A. & Kemner, K. M.
System: The UNT Digital Library
Welfare Reform: TANF Trends and Data (open access)

Welfare Reform: TANF Trends and Data

None
Date: July 20, 2004
Creator: Burke, Vee
System: The UNT Digital Library
Cost Analysis of Fuel Cell Systems for Transportation Compressed Hydrogen and PEM Fuel Cell System (open access)

Cost Analysis of Fuel Cell Systems for Transportation Compressed Hydrogen and PEM Fuel Cell System

PEMFC technology for transportation must be competitive with internal combustion engine powertrains in a number of key metrics, including performance, life, reliability, and cost. Demonstration of PEMFC cost competitiveness has its own challenges because the technology has not been applied to high volume automotive markets. The key stack materials including membranes, electrodes, bipolar plates, and gas diffusion layers have not been produced in automotive volumes to the exacting quality requirements that will be needed for high stack yields and to the evolving property specifications of high performance automotive stacks. Additionally, balance-of-plant components for air, water, and thermal management are being developed to meet the unique requirements of fuel cell systems. To address the question of whether fuel cells will be cost competitive in automotive markets, the DOE has funded this project to assess the high volume production cost of PEM fuel cell systems. In this report a historical perspective of our efforts in assessment of PEMFC cost for DOE is provided along with a more in-depth assessment of the cost of compressed hydrogen storage is provided. Additionally, the hydrogen storage costs were incorporated into a system cost update for 2004. Assessment of cost involves understanding not only material and production …
Date: October 20, 2004
Creator: Carlson, Eric J.
System: The UNT Digital Library
SOLID OXIDE FUEL CELL MANUFACTURING COST MODEL: SIMULATING RELATIONSHIPS BETWEEN PERFORMANCE, MANUFACTURING, AND COST OF PRODUCTION (open access)

SOLID OXIDE FUEL CELL MANUFACTURING COST MODEL: SIMULATING RELATIONSHIPS BETWEEN PERFORMANCE, MANUFACTURING, AND COST OF PRODUCTION

The successful commercialization of fuel cells will depend on the achievement of competitive system costs and efficiencies. System cost directly impacts the capital equipment component of cost of electricity (COE) and is a major contributor to the O and M component. The replacement costs for equipment (also heavily influenced by stack life) is generally a major contributor to O and M costs. In this project, they worked with the SECA industrial teams to estimate the impact of general manufacturing issues of interest on stack cost using an activities-based cost model for anode-supported planar SOFC stacks with metallic interconnects. An earlier model developed for NETL for anode supported planar SOFCs was enhanced by a linkage to a performance/thermal/mechanical model, by addition of Quality Control steps to the process flow with specific characterization methods, and by assessment of economies of scale. The 3-dimensional adiabatic performance model was used to calculate the average power density for the assumed geometry and operating conditions (i.e., inlet and exhaust temperatures, utilization, and fuel composition) based on publicly available polarizations curves. The SECA team provided guidance on what manufacturing and design issues should be assessed in this Phase I demonstration of cost modeling capabilities. They considered the …
Date: April 20, 2004
Creator: Carlson, Eric J.; Yang, Yong & Fulton, Chandler
System: The UNT Digital Library
Theory of Electron Transfer in Complex Systems (open access)

Theory of Electron Transfer in Complex Systems

This research grant is the most recent of a continuous series of grants from the Department of Energy supporting our theoretical efforts to understand various electron transfer processes. In part, my research on this topic has focused on distributions of electric fields, as it is these fields that drive electron transfer. Additional focus has been concerned with kinetics, as the rates of electron transfer are central to the utility of electron transfer. Finally, we have found that the theoretical tools we originally developed to treat electron transfer can be suitably applied to understand the workings of molecular motors.
Date: October 20, 2004
Creator: Chandler, David
System: The UNT Digital Library
PRODUCTION OF FOAMS, FIBERS AND PITCHES USING A COAL EXTRACTION PROCESS (open access)

PRODUCTION OF FOAMS, FIBERS AND PITCHES USING A COAL EXTRACTION PROCESS

This Department of Energy National Energy Technology Laboratory sponsored project developed processes for converting coal feedstocks to carbon products, including coal-derived pitch, coke foams and fibers based on solvent extraction processes. A key technology is the use of hydrogenation accomplished at elevated temperatures and pressures to obtain a synthetic coal pitch. Hydrogenation, or partial direct liquefaction of coal, is used to modify the properties of raw coal such that a molten synthetic pitch can be obtained. The amount of hydrogen required to produce a synthetic pitch is about an order of magnitude less than the amount required to produce synthetic crude oil. Hence the conditions for synthetic pitch production consume very little hydrogen and can be accomplished at substantially lower pressure. In the molten state, hot filtration or centrifugation can be used to separate dissolved coal chemicals from mineral matter and insolubles (inertinite), resulting in the production of a purified hydrocarbon pitch. Alternatively, if hydrogenation is not used, aromatic hydrocarbon liquids appropriate for use as precursors to carbon products can obtained by dissolving coal in a solvent. As in the case for partial direct liquefaction pitches, undissolved coal is removed via hot filtration or centrifugation. Excess solvent is boiled off …
Date: June 20, 2004
Creator: Chen, Chong; Kennel, Elliot B.; Magean, Liviu; Stansberry, Pete G.; Stiller, Alfred H. & Zondlo, John W.
System: The UNT Digital Library
Simulating the Flow Field Upstream of the Dworshak Dam Regulating Outlets (open access)

Simulating the Flow Field Upstream of the Dworshak Dam Regulating Outlets

The Pacific Northwest National Laboratory numerically modeled flow conditions upstream of the regulating outlets at Dworshak Dam, North Fork Clearwater River, Idaho. Simulations were performed using the computational fluid dynamics model Flow-3D, a peer reviewed and validated three-dimensional Reynolds-averaged Navier-Stokes hydrodynamic model. Results were studied to determine the impacts of water surface elevation and discharge though the three regulating outlets on flow velocities in the reservoir forebay. These simulations were in general support of a larger research program conducted by the Idaho Department of Fish and Game that is evaluating the efficacy of strobe lights to deter fish from entering the regulating outlets and powerhouse turbine intakes. Simulation results indicate that large variations in forebay water velocities occur over the typical range of regulating outlet operations and seasonal water surface fluctuations. As expected, water velocities generally increase with larger outlet gate openings and higher water surface elevations. Simulations span typical regulating outlet operations: forebay water surface elevations between 1460 ft and 1600 ft and regulating outlet gate valve openings between 1 ft and 10 ft open. In addition, simulations examined flow conditions when only one or two of the three regulating outlets were operating. The resulting matrix of 24 unique …
Date: March 20, 2004
Creator: Cook, Chris B. & Richmond, Marshall C.
System: The UNT Digital Library
OXIDATION OF BE AT ELEVATED TEMPERATURE (open access)

OXIDATION OF BE AT ELEVATED TEMPERATURE

None
Date: September 20, 2004
Creator: Cook, R C & Gunther, J
System: The UNT Digital Library
Federal Regulatory Reform: An Overview (open access)

Federal Regulatory Reform: An Overview

This report provides Congress with a broad overview of significant congressional and presidential regulatory reform efforts within the past 20 to 30 years.
Date: April 20, 2004
Creator: Copeland, Curtis W.
System: The UNT Digital Library
HIV/AIDS International Programs: Appropriations, FY2003-FY2005 (open access)

HIV/AIDS International Programs: Appropriations, FY2003-FY2005

The Administration's FY2005 request for international HIV/AIDS, tuberculosis, and malaria programs totals about $2.8 billion, as compared with $2.4 billion appropriated for FY2004. The FY2005 request includes a large increase for the bilateral Global AIDS Initiative, headquartered at the Department of State, while the request for the Global Fund to Fight AIDS, Tuberculosis, and Malaria is $200 million, compared with $546.7 million appropriated in FY2004.
Date: September 20, 2004
Creator: Copson, Raymond W.
System: The UNT Digital Library
How Accurately can we Calculate Thermal Systems? (open access)

How Accurately can we Calculate Thermal Systems?

I would like to determine how accurately a variety of neutron transport code packages (code and cross section libraries) can calculate simple integral parameters, such as K{sub eff}, for systems that are sensitive to thermal neutron scattering. Since we will only consider theoretical systems, we cannot really determine absolute accuracy compared to any real system. Therefore rather than accuracy, it would be more precise to say that I would like to determine the spread in answers that we obtain from a variety of code packages. This spread should serve as an excellent indicator of how accurately we can really model and calculate such systems today. Hopefully, eventually this will lead to improvements in both our codes and the thermal scattering models that they use in the future. In order to accomplish this I propose a number of extremely simple systems that involve thermal neutron scattering that can be easily modeled and calculated by a variety of neutron transport codes. These are theoretical systems designed to emphasize the effects of thermal scattering, since that is what we are interested in studying. I have attempted to keep these systems very simple, and yet at the same time they include most, if not …
Date: April 20, 2004
Creator: Cullen, D.; Blomquist, R. N.; Dean, C.; Heinrichs, D.; Kalugin, M. A.; Lee, M. et al.
System: The UNT Digital Library