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An Advanced Fracture Characterization and Well Path Navigation System for Effective Re-Development and Enhancement of Ultimate Recovery From the Complex Monterey Reservoir of South Ellwood Field, Offshore California, Quarterly Report: October - December 2004

Description: Venoco Inc, intends to re-develop the Monterey Formation, a Class III basin reservoir, at South Ellwood Field, Offshore Santa Barbara, California. Well productivity in this field varies significantly. Cumulative Monterey production for individual wells has ranged from 260 STB to 8,700,000 STB. Productivity is primarily affected by how well the well path connects with the local fracture system and the degree of aquifer support. Cumulative oil recovery to date is a small percentage of the original oil in place. To embark upon successful re-development and to optimize reservoir management, Venoco intends to investigate, map and characterize field fracture patterns and the reservoir conduit system. State of the art borehole imaging technologies including FMI, dipole sonic and cross-well seismic, interference tests and production logs will be employed to characterize fractures and micro faults. These data along with the existing database will be used for construction of a novel geologic model of the fracture network. Development of an innovative fracture network reservoir simulator is proposed to monitor and manage the aquifer's role in pressure maintenance and water production. The new fracture simulation model will be used for both planning optimal paths for new wells and improving ultimate recovery. In the second phase of this project, the model will be used for the design of a pilot program for downhole water re-injection into the aquifer simultaneously with oil production. Downhole water separation units attached to electric submersible pumps will be used to minimize surface fluid handling thereby improving recoveries per well and field economics while maintaining aquifer support. In cooperation with the DOE, results of the field studies as well as the new models developed and the fracture database will be shared with other operators. Numerous fields producing from the Monterey and analogous fractured reservoirs both onshore and offshore will benefit from the …
Date: January 31, 2005
Creator: Horner, Steve
Partner: UNT Libraries Government Documents Department
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Advanced Strained-Superlattice Photocathodes for Polarized Electron Sources

Description: Polarized electrons have been essential for high-energy parity-violating experiments and measurements of the nucleon spin structure. The availability of a polarized electron beam was crucial to the success of the Stanford Linear Collider (SLC) in achieving a precise measurement of the electroweak mixing angle, and polarized electron beams will be required for all future linear colliders. Polarized electrons are readily produced by GaAs photocathode sources. When a circularly polarized laser beam tuned to the bandgap minimum is directed to the negative-electron-affinity (NEA) surface of a GaAs crystal, longitudinally polarized electrons are emitted into vacuum. The electron polarization is easily reversed by reversing the laser polarization. The important properties of these photocathodes for accelerator applications are: degree of polarization of the extracted beam; ability to extract sufficient charge to meet accelerator pulse-structure requirements; efficiency and stability of operation; and absence of any asymmetries in the beam properties (charge, position, energy, etc.) upon polarization reversal. The performance of GaAs photocathodes has improved significantly since they were first introduced in 1978 [1]. The theoretical maximum polarization of 50% for natural GaAs was first exceeded in 1991 using the lattice mismatch of a thin InGaAs layer epitaxially grown over a GaAs substrate to generate a strain in the former that broke the natural degeneracy between the heavy- and light-hole valence bands [2]. Polarizations as high as 78% were produced for the SLC from photocathodes based on a thin GaAs epilayer grown on GaAsP [3,4]. After 10 years of experience with many cathode samples at several laboratories [5], the maximum polarization using the GaAs/GaAsP single strained-layer cathode remained limited to 80%, while the quantum efficiency (QE) for a 100-nm epilayer is only 0.3% or less. Two factors were known to limit the polarization of these cathodes: (1) the limited band splitting; and (2) a relaxation …
Date: January 31, 2005
Creator: Moy, Dr. Aaron
Partner: UNT Libraries Government Documents Department
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Advancing New 3D Seismic Interpretation Methods for Exploration and Development of Fractured Tight Gas Reservoirs

Description: In a study funded by the U.S. Department of Energy and GeoSpectrum, Inc., new P-wave 3D seismic interpretation methods to characterize fractured gas reservoirs are developed. A data driven exploratory approach is used to determine empirical relationships for reservoir properties. Fractures are predicted using seismic lineament mapping through a series of horizon and time slices in the reservoir zone. A seismic lineament is a linear feature seen in a slice through the seismic volume that has negligible vertical offset. We interpret that in regions of high seismic lineament density there is a greater likelihood of fractured reservoir. Seismic AVO attributes are developed to map brittle reservoir rock (low clay) and gas content. Brittle rocks are interpreted to be more fractured when seismic lineaments are present. The most important attribute developed in this study is the gas sensitive phase gradient (a new AVO attribute), as reservoir fractures may provide a plumbing system for both water and gas. Success is obtained when economic gas and oil discoveries are found. In a gas field previously plagued with poor drilling results, four new wells were spotted using the new methodology and recently drilled. The wells have estimated best of 12-months production indicators of 2106, 1652, 941, and 227 MCFGPD. The latter well was drilled in a region of swarming seismic lineaments but has poor gas sensitive phase gradient (AVO) and clay volume attributes. GeoSpectrum advised the unit operators that this location did not appear to have significant Lower Dakota gas before the well was drilled. The other three wells are considered good wells in this part of the basin and among the best wells in the area. These new drilling results have nearly doubled the gas production and the value of the field. The interpretation method is ready for commercialization and gas exploration and …
Date: January 31, 2005
Creator: Reeves, James
Partner: UNT Libraries Government Documents Department
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Army National Guard: Inefficient, Error-Prone Process Results in Travel Reimbursement Problems for Mobilized Soldiers

Description: A letter report issued by the Government Accountability Office with an abstract that begins "GAO was asked to determine (1) the impact of the recent increased operational tempo on the process used to reimburse Army Guard soldiers for travel expenses and the effect that travel reimbursement problems have had on soldiers and their families; (2) the adequacy of the overall design of controls over the processes, human capital, and automated systems relied on for Army Guard travel reimbursements; and (3) whether the Department of Defense's (DOD) current efforts to automate its travel reimbursement process will resolve the problems identified. GAO selected and audited 10 case study units that were identified in a preliminary assessment as having a variety of travel reimbursement problems."
Date: January 31, 2005
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department
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BIG SKY CARBON SEQUESTRATION PARTNERSHIP

Description: The Big Sky Carbon Sequestration Partnership, led by Montana State University, is comprised of research institutions, public entities and private sectors organizations, and the Confederated Salish and Kootenai Tribes and the Nez Perce Tribe. Efforts under this Partnership in Phase I fall into four areas: evaluation of sources and carbon sequestration sinks that will be used to determine the location of pilot demonstrations in Phase II; development of GIS-based reporting framework that links with national networks; designing an integrated suite of monitoring, measuring, and verification technologies and assessment frameworks; and initiating a comprehensive education and outreach program. The groundwork is in place to provide an assessment of storage capabilities for CO{sub 2} utilizing the resources found in the Partnership region (both geological and terrestrial sinks), that would complement the ongoing DOE research. Efforts are underway to showcase the architecture of the GIS framework and initial results for sources and sinks. The region has a diverse array of geological formations that could provide storage options for carbon in one or more of its three states. Likewise, initial estimates of terrestrial sinks indicate a vast potential for increasing and maintaining soil C on forested, agricultural, and reclaimed lands. Both options include the potential for offsetting economic benefits to industry and society. Steps have been taken to assure that the GIS-based framework is consistent among types of sinks within the Big Sky Partnership area and with the efforts of other western DOE partnerships. The Partnership recognizes the critical importance of measurement, monitoring, and verification technologies to support not only carbon trading but all policies and programs that DOE and other agencies may want to pursue in support of GHG mitigation. The efforts in developing and implementing MMV technologies for geological sequestration reflect this concern. Research is also underway to identify and validate best …
Date: January 31, 2005
Creator: Capalbo, Susan M.
Partner: UNT Libraries Government Documents Department
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BOILER MATERIALS FOR ULTRASUPERCRITICAL COAL POWER PLANTS

Description: The U.S. Department of Energy (DOE) and the Ohio Coal Development Office (OCDO) have recently initiated a project aimed at identifying, evaluating, and qualifying the materials needed for the construction of the critical components of coal-fired boilers capable of operating at much higher efficiencies than current generation of supercritical plants. This increased efficiency is expected to be achieved principally through the use of ultrasupercritical steam conditions (USC). The project goal initially was to assess/develop materials technology that will enable achieving turbine throttle steam conditions of 760 C (1400 F)/35 MPa (5000 psi), although this goal for the main steam temperature had to be revised down to 732 C (1350 F), based on a preliminary assessment of material capabilities. The project is intended to build further upon the alloy development and evaluation programs that have been carried out in Europe and Japan. Those programs have identified ferritic steels capable of meeting the strength requirements of USC plants up to approximately 620 C (1150 F) and nickel-based alloys suitable up to 700 C (1300 F). In this project, the maximum temperature capabilities of these and other available high-temperature alloys are being assessed to provide a basis for materials selection and application under a range of conditions prevailing in the boiler. This report provides a quarterly status report for the period of July 1 to September 30, 2004.
Date: January 31, 2005
Creator: Viswanathan, R.; Coleman, K.; Shingledecker, J.; Sarver, J.; Stanko, G.; Borden, M. et al.
Partner: UNT Libraries Government Documents Department
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Charitable Contributions of Food Inventory: Proposals for Change

Description: Early in the 109th Congress, both S. 6, the Family and Community Protection Act of 2005, and S. 94, the Good Samaritan Hunger Relief Tax Incentive Act, have been introduced to encourage gifts of food by businesses for charitable purposes. While current law provides a deduction only to C corporations, these bills would expand the tax break to all business entities. The value of the existing deduction is the corporation’s basis in the donated product plus one half of the amount of appreciation, as long as that amount is less than twice the corporation’s basis in the product.
Date: January 31, 2005
Creator: Talley, Louis Alan & Jackson, Pamela J.
Partner: UNT Libraries Government Documents Department
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CO{Sub 2} Capture by Absorption With Potassium Carbonate

Description: The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. Thermodynamic modeling predicts that the heat of desorption of CO{sub 2} from 5m K+/2.5 PZ from 85 kJ/mole at 40 C to 30 kJ/mole at 120 C. Mass transfer modeling of this solvent suggests that carbonate and general salt concentration play a major role in catalyzing the rate of reaction of CO{sub 2} with piperazine. Stripper modeling suggests that with the multipressure stripper, the energy consumption with a generic solvent decreases by 15% as the heat of desorption is decreased from 23.8 to 18.5 kcal/gmol. A second pilot plant campaign with 5m K+/2.5 PZ was successfully completed.
Date: January 31, 2005
Creator: Rochelle, Gary T.; Cullinane, J.Tim; Hilliard, Marcus; Chen, Eric; Oyenekan, Babatunde & Dugas, Ross
Partner: UNT Libraries Government Documents Department
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CO2 Selective Ceramic Membrane for Water-Gas-Shift Reaction With Concomitant Recovery of CO2, Quarterly Report: October - December 2004

Description: Our CO{sub 2}-affinity material synthesis activities thus far have offered two base materials suitable for hydrogen production via low temperature water gas shift reaction (LTS-WGS) with concomitant removal of CO{sub 2} for sequestration. They include (i) a nanoporous CO{sub 2}-affinity membrane and (ii) a hydrotalcite based CO-affinity adsorbent. These two materials offer a commercially viable opportunity for implementing an innovative process concept termed the hybrid adsorbent-membrane reactor (HAMR) for LTS-WGS, proposed by us in a previous quarterly report. A complete mathematical model has been developed in this quarter to describe the HAMR system, which offers process flexibility to incorporate both catalysts and adsorbents in the reactor as well as permeate sides. In comparison with the preliminary mathematical model we reported previously, this improved model incorporates ''time'' as an independent variable to realistically simulate the unsteady state nature of the adsorptive portion of the process. In the next quarterly report, we will complete the simulation to demonstrate the potential benefit of the proposed process based upon the performance parameters experimentally obtained from the CO{sub 2}-affinity adsorbent and membrane developed from this project.
Date: January 31, 2005
Creator: Liu, Paul K. T.
Partner: UNT Libraries Government Documents Department
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Coast Guard: Station Readiness Improving, but Resource Challenges and Management Concerns Remain

Description: A letter report issued by the Government Accountability Office with an abstract that begins "For years, the Coast Guard has conducted search and rescue operations from its network of stations along the nation's coasts and waterways. In 2001, reviews of station operations found that station readiness--the ability to execute mission requirements in keeping with standards--was in decline. The Coast Guard began addressing these issues, only to see its efforts complicated by expanded post-September 11, 2001, homeland security responsibilities at many stations. GAO reviewed the impact of changing missions on station needs, the progress made in addressing station readiness needs, and the extent to which plans are in place for addressing any remaining needs."
Date: January 31, 2005
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department
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Continuity of Operations (COOP) in the Executive Branch: Issues in the 109th Congress

Description: Spurred in part by occasional warnings of potential terrorist threats in the post- 9/11 era, some policymakers have intensified their focus on continuity of operations (COOP) issues. COOP planning is a segment of federal government contingency planning linked to continuity of government (COG). Together, COOP and COG are designed to ensure survival of a constitutional form of government and the continuity of essential federal functions. This report focuses primarily on executive branch COOP activities.
Date: January 31, 2005
Creator: Petersen, R. Eric
Partner: UNT Libraries Government Documents Department
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Criminal Debt: Court-Ordered Restitution Amounts Far Exceed Likely Collections for the Crime Victims in Selected Financial Fraud Cases

Description: A letter report issued by the Government Accountability Office with an abstract that begins "In the wake of a recent wave of corporate scandals, Senator Byron L. Dorgan noted that the American taxpayers have a right to expect that those who have committed corporate fraud and other criminal wrongdoing will be punished, and that the federal government will make every effort to recover assets held by the offenders. Recognizing that GAO previously reported on deficiencies in the Department of Justice's (Justice) criminal debt collection processes (GAO-01-664), Senator Dorgan asked GAO to review selected criminal white-collar financial fraud cases for which large restitution debts have been established but little has been collected. Specifically, GAO was asked to determine (1) the status of Justice's efforts to collect on the outstanding debt, (2) the prospects for future collections, and (3) whether specific problems have affected Justice's ability to collect the debt."
Date: January 31, 2005
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department
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DESIGN AND EVALUATION OF IONIC LIQUIDS AS NOVEL CO2 ABSORBENTS

Description: Progress from the second quarter of activity on the project ''Design and Evaluation of Ionic Liquids as Novel CO2 Absorbents'' is provided. Major activities in three areas are reported: ''compound synthesis, property measurement and molecular modeling''. Two new ionic liquid compounds have been synthesized and characterized. Viscosities, densities and gas solubilities have been measured for several of the ionic liquids synthesized during Q1. Continued progress on computational modeling of the ionic liquids has been made.
Date: January 31, 2005
Creator: Maginn, Edward J.
Partner: UNT Libraries Government Documents Department
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Determining the mechanical constitutive properties of metals as a function of strain rate and temperature: A combined experimental and modeling approach; Progress Report for 2004

Description: Development and validation of constitutive models for polycrystalline materials subjected to high strain rate loading over a range of temperatures are needed to predict the response of engineering materials to in-service type conditions (foreign object damage, high-strain rate forging, high-speed sheet forming, deformation behavior during forming, response to extreme conditions, etc.). To account accurately for the complex effects that can occur during extreme and variable loading conditions, requires significant and detailed computational and modeling efforts. These efforts must be closely coupled with precise and targeted experimental measurements that not only verify the predictions of the models, but also provide input about the fundamental processes responsible for the macroscopic response. Achieving this coupling between modeling and experimentation is the guiding principle of this program. Specifically, this program seeks to bridge the length scale between discrete dislocation interactions with grain boundaries and continuum models for polycrystalline plasticity. Achieving this goal requires incorporating these complex dislocation-interface interactions into the well-defined behavior of single crystals. Despite the widespread study of metal plasticity, this aspect is not well understood for simple loading conditions, let alone extreme ones. Our experimental approach includes determining the high-strain rate response as a function of strain and temperature with post-mortem characterization of the microstructure, quasi-static testing of pre-deformed material, and direct observation of the dislocation behavior during reloading by using the in situ transmission electron microscope deformation technique. These experiments will provide the basis for development and validation of physically-based constitutive models, which will include dislocation-grain boundary interactions for polycrystalline systems. One aspect of the program will involve the direct observation of specific mechanisms of micro-plasticity, as these will indicate the boundary value problem that should be addressed. This focus on the pre-yield region in the quasi-static effort (the elasto-plastic transition) is also a tractable one from an experimental and …
Date: January 31, 2005
Creator: Robertson, I.; Beaudoin, A. & Lambros, J.
Partner: UNT Libraries Government Documents Department
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DEVELOPING STATE POLICIES SUPPORTIVE OF BIOENERGY DEVELOPMENT

Description: Working within the context of the Southern States Biobased Alliance (SSBA) and with officials in each state, the Southern States Energy Board (SSEB) is identifying bioenergy-related policies and programs within each state to determine their impact on the development, deployment or use of bioenergy. In addition, SSEB will determine which policies have impacted industry's efforts to develop, deploy or use biobased technologies or products. As a result, SSEB will work with the Southern States Biobased Alliance to determine how policy changes might address any negative impacts or enhance positive impacts. In addition to analysis of domestic policies and programs, this project will include the development of a U.S.-Brazil Biodiesel Pilot Project. The purpose of this effort is to promote and facilitate the commercialization of biodiesel and bioenergy production and demand in Brazil.
Date: January 31, 2005
Creator: Baskin, Kathryn
Partner: UNT Libraries Government Documents Department
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Distributed Physical and Molecular Separations for Selective Harvest of Higher Value Wheat Straw Components Project

Description: Wheat straw (Triticum aestivum L.) is an abundant source of plant fiber. It is regenerated, in large quantities, every year. At present, this potentially valuable resource is greatly under-exploited. Most of the excess straw biomass (i.e., tonnage above that required for agronomic cropping system sustainability) is managed through expensive chopping/tillage operations and/or burnt in the field following harvest, resulting in air pollution and associated health problems. Potential applications for wheat straw investigated within this project include energy and composites manufacture. Other methods of straw utilization that will potentially benefit from the findings of this research project include housing and building, pulp and paper, thermal insulation, fuels, and chemicals. This project focused on components of the feedstock assembly system for supplying a higher value small grains straw residue for (1) gasification/combustion and (2) straw-thermoplastic composites. This project was an integrated effort to solve the technological, infrastructural, and economic challenges associated with using straw residue for these bioenergy and bioproducts applications. The objective of the research is to contribute to the development of a low-capital distributed harvesting and engineered storage system for upgrading wheat straw to more desirable feedstocks for combustion and for straw-plastic composites. We investigated two processes for upgrading wheat straw to a more desirable feedstock: (1) An efficient combine-based threshing system for separating the internodal stems from the leaves, sheaths, nodes, and chaff. (2) An inexpensive biological process using white-rot fungi to improve the composition of the mechanically processed straw stems.
Date: January 31, 2005
Creator: Hess, J.R
Partner: UNT Libraries Government Documents Department
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Elevated-Temperature Ferritic and Martensitic Steels and Their Application to Future Nuclear Reactors

Description: In the 1970s, high-chromium (9-12% Cr) ferritic/martensitic steels became candidates for elevated-temperature applications in the core of fast reactors. Steels developed for conventional power plants, such as Sandvik HT9, a nominally Fe-12Cr-1Mo-0.5W-0.5Ni-0.25V-0.2C steel (composition in wt %), were considered in the United States, Europe, and Japan. Now, a new generation of fission reactors is in the planning stage, and ferritic, bainitic, and martensitic steels are again candidates for in-core and out-of-core applications. Since the 1970s, advances have been made in developing steels with 2-12% Cr for conventional power plants that are significant improvements over steels originally considered. This paper will review the development of the new steels to illustrate the advantages they offer for the new reactor concepts. Elevated-temperature mechanical properties will be emphasized. Effects of alloying additions on long-time thermal exposure with and without stress (creep) will be examined. Information on neutron radiation effects will be discussed as it applies to ferritic and martensitic steels.
Date: January 31, 2005
Creator: Klueh, RL
Partner: UNT Libraries Government Documents Department
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"Energetics of Nanomaterials"

Description: This project represents a three-year collaboration among Alexandra Navrotsky, Brian Woodfield, Juliana Bocrio-Goates and Frances Hellman. It's purpose has been to explore the differences between bulk materials, nanoparticles, and thin films in terms of their thermodynamic properties, with an emphasis on heat capacities and entropies, as well as enthalpies. The three groups have brought very different expertise and capabilities to the project. Navrotsky is a solid-state chemist and geochemist, with a unique Thermochemistry Facility emphasizing enthalpy of formation measurements by high temperature oxide melt and room temperature acid solution calorimetry. Bocrio-Goates and Woodfield are physical chemists with unique capabilities in accurate cryogenic heat capacity measurements using adiabatic calorimetry. Hellman is a physicist with expertise in magnetism and heat capacity measurements using microscale ''detector on a chip'' calorimetric technology that she pioneered. The overarching question of the work is ''How does the free energy play out in nanoparticles''? or ''How do differences in free energy affect overall nanoparticle behavior''? Because the free energy represents the temperature-dependent balance between the enthalpy of a system and its entropy, there are two separate, but related, components to the experimental investigations: Solution calorimetric measurements provide the energetics and two types of heat capacity measurements the entropy. They use materials that are well characterized in other ways (structurally, magnetically, and chemically), and samples are shared across the collaboration.
Date: January 31, 2005
Creator: Navrotsky, Professor Alexandra
Partner: UNT Libraries Government Documents Department
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Engineering and Physics Optimization of Breed and Burn Fast Reactor Systems; NUCLEAR ENERGY RESEARCH INITIATIVE (NERI) QUARTERLY PROGRESS REPORT

Description: This project is organized under four major tasks (each of which has two or more subtasks) with contributions among the three collaborating organizations (MIT, INEEL and ANL-West): Task A: Core Physics and Fuel Cycle; Task B: Core Thermal Hydraulics; Task C: Plant Design; Task D: Fuel Design The lead PI, Michael J. Driscoll, has consolidated and summarized the technical progress submissions provided by the contributing investigators from all sites, under the above principal task headings.
Date: January 31, 2005
Creator: Hejzlar, Pavel; Yarsky, Peter; Driscoll, Mike; Wachs, Dan; Weaver, Kevan; Czerwinski, Ken et al.
Partner: UNT Libraries Government Documents Department
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Federal-Aid Highways: FHWA Needs a Comprehensive Approach to Improving Project Oversight

Description: A letter report issued by the Government Accountability Office with an abstract that begins "The federal-aid highway program provides over $25 billion a year to states for highway and bridge projects, often paying 80 percent of these projects' costs. The federal government provides funding for and oversees this program, while states largely choose and manage the projects. Ensuring that states effectively control the cost and schedule performance of these projects is essential to ensuring that federal funds are used efficiently. We reviewed the Federal Highway Administration's (FHWA) approach to improving its federal-aid highway project oversight efforts since we last reported on it in 2002, including (1) FHWA's oversight-related goals and performance measures, (2) FHWA's oversight improvement activities, (3) challenges FHWA faces in improving project oversight, and (4) best practices for project oversight."
Date: January 31, 2005
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department
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Final Report: Feasibility Study of Biomass in Snohomish County, Washington

Description: This report and its attachments summarizes the results of a unique tribal-farmer cooperative study to evaluate the feasibility of building one or more regional anaerobic digestion systems in Snohomish County, Washington.
Date: January 31, 2005
Creator: Williams, Daryl & Clark, Ray
Partner: UNT Libraries Government Documents Department
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Final Report Providing the Design for Low-Cost Wireless Current Transducer and Electric Power Sensor Prototype

Description: This report describes the design and development of a wireless current transducer and electric power sensor prototype. The report includes annotated schematics of the power sensor circuitry and the printed circuit board. The application program used to illustrate the functionality of the wireless sensors is described in this document as well.
Date: January 31, 2005
Creator: Kintner-Meyer, Michael CW; Burghard, Brion J. & Reid, Larry D.
Partner: UNT Libraries Government Documents Department
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Hardness of Carburized Surfaces in 316LN Stainless Steel after Low Temperature Neutron Irradiation

Description: A proprietary surface carburization treatment is being considered to minimize possible cavitation pitting of the inner surfaces of the stainless steel target vessel of the SNS. The treatment gives a large supersaturation of carbon in the surface layers and causes substantial hardening of the surface. To answer the question of whether such a hardened layer will remain hard and stable during neutron irradiation, specimens of the candidate materials were irradiated in the High Flux Isotope Reactor (HFIR) to an atomic displacement level of 1 dpa. Considerable radiation hardening occurred in annealed 316LN stainless steel and 20% cold rolled 316LN stainless steel, and lesser radiation hardening in Kolsterised layers on these materials. These observations coupled with optical microscopy examinations indicate that the carbon-supersaturated layers did not suffer radiation-induced decomposition and softening.
Date: January 31, 2005
Creator: Byun, TS
Partner: UNT Libraries Government Documents Department
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Impermeable thin AI2O3 overlay for TBC protection from sulfate and vanadate attack in gas turbines

Description: 25 {micro}m and a 2 {micro}m thick Al{sub 2}O{sub 3} overlay were deposited by HVOF thermal spray and by sol-gel coating method, respectively, onto to the surface of YSZ coating. Indenter test was employed to investigate the spalling of YSZ with and without Al{sub 2}O{sub 3} overlay after hot corrosion. The results showed that Al{sub 2}O{sub 3} overlay acted as a barrier against the infiltration of the molten salt into the YSZ coating during exposure, thus significantly reduced the amount of M-phase of ZrO{sub 2} in YSZ coating. Thick Al{sub 2}O{sub 3} overlay will increase compressive stress and failure in TBC. During next reporting time, Al{sub 2}O{sub 3} overlay will be deposited on the YSZ surface by the composite-sol-gel route (CSG). Hot corrosion tests will be carried out on the TBC.
Date: January 31, 2005
Creator: Mao, Scott X.
Partner: UNT Libraries Government Documents Department
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