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Report on the TCO/GCP Terrestrial Carbon Observations and Model-Data Fusion Workshop

Description: The global carbon cycle is of intense interest to policy-makers, the scientific community, and public organizations. As a result, numerous new programmes and projects have been developed over the last few years. TCO and GCP are two such complementary initiatives which share a common goal of advancing the availability of more accurate and mutually consistent estimates of terrestrial carbon sources, sinks and processes, regionally and globally, through syntheses of observations and models. The workshop was intended to advance the availability of more accurate and mutually consistent estimates of the distribution of carbon sources and sinks at a regional and global level. This goal can be achieved by convergence of in situ and satellite observations, experiments and modelling strategies; improvements in data acquisition and sharing; and product generation, distribution and use. The workshop focused on the following questions and associated issues: 1. What carbon cycle data products could be routinely produced from a carbon observation system based on model-data and model-data fusion? 2. What are the main conceptual approaches to assimilating atmospheric carbon content, terrestrial carbon flux and remotely sensed data into coupled atmospheric circulation-carbon cycle models? 3. What is the present and eventual uncertainty regarding the main carbon fluxes at global and regional scale, and how will it be reduced by projects currently underway and about to begin? 4. In what regions, and on what topics, will new data inputs make the largest contribution to reducing the residual uncertainties? What actions should be taken to overcome the gaps and limitations identified?
Date: June 2003
Creator: Quegan, Shaun
Partner: UNT Libraries
open access

Two-photon exchange and elastic electron-proton scattering

Description: Two-photon exchange contributions to elastic electron-proton scattering cross sections are evaluated in a simple hadronic model including the finite size of the proton. The corrections are found to be small, but with a strong angular dependence at fixed Q{sup 2}. This is significant for the Rosenbluth technique for determining the ratio of electric and magnetic form factors of the proton, and partly reconciles the apparent discrepancy with the results of the polarization transfer technique.
Date: June 1, 2003
Creator: Blunden, Peter; Melnitchouk, Wolodymyr & Tjon, John
Partner: UNT Libraries Government Documents Department
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Characterization of Turbiditic Oil Reservoirs Based on Geophysical Models of Their Formation

Description: Two aspects of the characterization of turbiditic oil reservoirs based on geophysical models of their formation are discussed in this report. First, we have developed a new, more accurate and computationally faster finite-element method (FEM) for simulating the flow and deposition of turbidity currents. Although a finite volume method had been presented and discussed in a previous report, it was discovered to be insufficient for our purposes of simulating turbidity flows. The new method allows variable grids near the regions of large deposition, which are of most interest, and numerically results in banded, sparse matrices that are much faster to solve. Examples of the success of the method are presented. In the second part of this report, we present and discuss a preliminary study on the feasibility of matching the results of a sediment transport model to field data. With the simulation of the turbidity current we can create an entire turbiditic deposit. This requires the initial conditions of the flow, such as the amount of sediment, the volume or flow rate of the current, etc, which are of course unavailable. This requires an estimate of the initial conditions of the flow, which can be determined from limited data from the deposit. We used the Excel optimization routine Solver to reproduce a one-dimensional algebraically simulated deposit with and without measurement noise. Results indicate that such matching is feasible, provided that the noise is below certain thresholds, dependent on the size of the deposit and the number data points constraining the parameter estimation.
Date: June 1, 2003
Creator: Bonnecaze, Roger T. & Lakshminarasimhan, Srivatsan
Partner: UNT Libraries Government Documents Department
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Solid State Energy Conversion Alliance Delphi SOFC

Description: The objective of Phase I under this project is to develop a 5 kW Solid Oxide Fuel Cell power system for a range of fuels and applications. During Phase I, the following will be accomplished: Develop and demonstrate technology transfer efforts on a 5 kW stationary distributed power generation system that incorporates steam reforming of natural gas with piped-in water (Demonstration System A); and Initiate development of a 5 kW system for later mass-market automotive auxiliary power unit application, which will incorporate Catalytic Partial Oxidation (CPO) reforming of gasoline, with anode exhaust gas injected into an ultra-lean burn internal combustion engine. This technical progress report covers work performed by Delphi from July through December 2002 under Department of Energy Cooperative Agreement DE-FC-02NT41246 for the 5 kW mass-market automotive (gasoline) auxiliary power unit. This report highlights technical results of the work performed under the following tasks for the automotive 5 kW system: Task 1--System Design and Integration; Task 2--Solid Oxide Fuel Cell Stack Developments; Task 3--Reformer Developments; Task 4--Development of Balance of Plant (BOP) Components; Task 5--Manufacturing Development (Privately Funded); Task 6--System Fabrication; and Task 7--System Testing.
Date: June 9, 2003
Creator: Shaffer, Steven; Kelly, Sean; Mukerjee, Subhasish; Schumann, David & Mieney, H. Skip
Partner: UNT Libraries Government Documents Department
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Correlation of point defects in CdZnTe with charge transport:application to room-temperature x-ray and gamma-ray. Final Technical Report

Description: The primary goal of this project has been to characterize and identify point defects (e.g., impurities, vacancies, vacancy-impurity complexes, etc.) in CdZnTe and determine the mechanisms by which these defects influence the carrier {mu}{tau}products. Special attention is given to the role of shallow donors, shallow acceptors, and deeper acceptors. There are two experimental focus areas in the project: (1) liquid-helium photoluminescence (PL) and PL excitation spectroscopy are used to identify and characterize donors and acceptors and to determine zinc molar fraction; and (2) electron paramagnetic resonance (EPR) and photoinduced EPR experiments are performed at liquid-helium temperature to identify paramagnetic point defects and to determine the concentration of these defects. Results from the two experimental focus areas are correlated with detector performance parameters (e.g., electron and hole {mu}{tau} products), crystal growth conditions, and microstructure analyses.
Date: June 25, 2003
Creator: Giles, Nancy C.
Partner: UNT Libraries Government Documents Department
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The Engineered Phytoremediation of Ionic and Methylmercury Pollution

Description: Our current specific objectives are to use transgenic plants to control the chemical species, electrochemical state, and above ground binding of mercury to (a) prevent methylmercury from entering the food-chain, (b) remove mercury from polluted sites, and (c) hyperaccumulate mercury in above ground tissues for later harvest.
Date: June 24, 2003
Creator: Meagher, Richard; Marshburn, Sarah; Heaton, Andrew; Zimer, Anne Marie & Rahman, Raoufa
Partner: UNT Libraries Government Documents Department
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The CDF silicon vertex trigger

Description: The CDF experiment's Silicon Vertex Trigger is a system of 150 custom 9U VME boards that reconstructs axial tracks in the CDF silicon strip detector in a 15 {mu}sec pipeline. SVT's 35 {mu}m impact parameter resolution enables CDF's Level 2 trigger to distinguish primary and secondary particles, and hence to collect large samples of hadronic bottom and charm decays. We review some of SVT's key design features. Speed is achieved with custom VLSI pattern recognition, linearized track fitting, pipelining, and parallel processing. Testing and reliability are aided by built-in logic state analysis and test-data sourcing at each board's input and output, a common inter-board data link, and a universal ''Merger'' board for data fan-in/fan-out. Speed and adaptability are enhanced by use of modern FPGAs.
Date: June 23, 2003
Creator: Ashmanskas, B.; Barchiesi, A. & Bardi, A.
Partner: UNT Libraries Government Documents Department
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New aspects of beam-beam interactions in hadron colliders

Description: Beam-beam phenomena have until now limited the beam currents and luminosity achievable in the Tevatron. injected proton currents are about ten times larger than the anti-proton currents so beam-beam effects have largely acted on the anti-protons and at all stages of the operational cycle. The effects of the anti-protons on the protons have until now been relatively benign but that may change at higher anti-proton currents. After 36 bunches of protons are injected and placed on the proton helix, anti-protons are injected four bunches at a time. After all bunches are injected, acceleration to top energy takes bout 85 seconds. After reaching flat top, the optics around the interaction regions (IRs) is changed to lower {beta}* from 1.6 m to 0.35 m at B0 and D0. The beams are brought into collision by collapsing the separation bumps around the IPs. During a high energy physics store each bunch experiences two head-on collisions with bunches in the opposing beam and seventy long-range interactions. At all other stages of the operational cycle, each bunch experiences only long-range interactions--seventy two in all. Performance limitations from beam-beam effects until now have been primarily due to these long-range interactions. The anti-proton losses at 150 GeV have decreased during the last year mostly due to better control of the orbits, tunes and chromaticities. During this period proton intensities have increased about 50%, thus anti-proton losses at 150 GeV have not been very dependent on proton intensities. Anti-proton and proton losses on the ramp together with proton losses at 150 GeV are the dominant contributors to the Tevatron inefficiency.
Date: June 2, 2003
Creator: Sen, Tanaji
Partner: UNT Libraries Government Documents Department
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Top quark production cross-section at the Tevatron Run 2

Description: The top quark pair production cross-section {sigma}{sub t{bar t}} has been measured in p{bar p} collisions at center of mass energies of 1.96 TeV using Tevatron Run 2 data. In the beginning of Run 2 both CDF and D0 {sigma}{sub t{bar t}} measurements in the dilepton channel t{bar t} {yields} WbW{bar b} {yields} {bar {ell}}{nu}{sub {ell}}b{ell}{prime} {bar {nu}}{sub {ell}{prime}}{bar b} and in the lepton plus jets channel t{bar t} {yields} WbW{bar b} {yields} q{bar q}{prime} b{ell}{bar {nu}}{sub {ell}}{bar b} + {bar {ell}}{nu}{sub {ell}}bq{bar q}{prime} {bar b} agree with the NLO (Next-to-Leading-Order) theoretical predictions. The presence of a top signal in Tevatron data has been reestablished.
Date: June 4, 2003
Creator: Cabrera, S.
Partner: UNT Libraries Government Documents Department
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Theoretical studies of beam-beam effects in the Tevatron at collision energy

Description: The dynamics due to the long-range beam-beam interactions depends on several beam parameters such as tunes, coupling, chromaticities, beam separations, intensities and emittances. They have developed analytical tools to calculate, for example, amplitude dependent tune shifts and chromaticities, beam-beam induced coupling, and betatron and synchro-betatron resonance widths. They report on these calculations and dynamic aperture calculations with long-term tracking. These theoretical results are compared with observations at collision energy and used to predict performance at design values of beam intensities and emittances.
Date: June 9, 2003
Creator: Sen, T.; Erdelyi, B. & Xiao, M.
Partner: UNT Libraries Government Documents Department
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Subsurface void detection using seismic tomographic imaging

Description: Tomographic imaging has been widely used in scientific and medical fields to remotely image media in a nondestructive way. This paper introduces a spectrum of seismic imaging applications to detect and characterize voids in coal mines. The application of seismic waves to detect changes in coal relies on two types of waves: body waves refracted along the interface between coal and bedrock (i.e., refracted P-waves) and channel waves that propagate directly through the coal (dispersive wave trains of the Rayleigh or Love type). For example, a P-wave tomography study to find underlying old mine workings in a coal mine in England, produced velocity patterns that revealed increases in velocity where high stress concentrations occur in the rock, which are most likely connected to old pillars left in support of the old working areas. At the same time, low velocities were found in areas of low stress concentrations, which are related to roof collapses indicating the locations of mined areas below. The application of channel wave tomography to directly image the presence of gaseous CO{sub 2} in a low velocity oil reservoir showed that the injected CO{sub 2} followed an ancient flow channel in the reservoir migrating from the injector to the producer well. The study showed how channel waves are preferable over refracted P-waves, as the latter were only marginally affected by the presence of the gas in the low-velocity channel. Similar approaches show great promise for the detection of voids in coal mines. Finally, a newly developed technique, based on scattering theory, revealed that the location and the size of a subsurface cavity could be accurately determined even in the presence of strong correlated and uncorrelated noise.
Date: June 26, 2003
Creator: Gritto, Roland
Partner: UNT Libraries Government Documents Department
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OPTICAL FIBER SENSOR TECHNOLOGIES FOR EFFICIENT AND ECONOMICAL OIL RECOVERY

Description: Efficient recovery of petroleum reserves from existing oil wells has been proven to be difficult due to the lack of robust instrumentation that can accurately and reliably monitor processes in the downhole environment. Commercially available sensors for measurement of pressure, temperature, and fluid flow exhibit shortened lifetimes in the harsh downhole conditions, which are characterized by high pressures (up to 20 kpsi), temperatures up to 250 C, and exposure to chemically reactive fluids. Development of robust sensors that deliver continuous, real-time data on reservoir performance and petroleum flow pathways will facilitate application of advanced recovery technologies, including horizontal and multilateral wells. This is the final report for the four-year program ''Optical Fiber Sensor Technologies for Efficient and Economical Oil Recovery'', funded by the National Petroleum Technology Office of the U.S. Department of Energy, and performed by the Center for Photonics Technology of the Bradley Department of Electrical and Computer Engineering at Virginia Tech from October 1, 1999 to March 31, 2003. The main objective of this research program was to develop cost-effective, reliable optical fiber sensor instrumentation for real-time monitoring of various key parameters crucial to efficient and economical oil production. During the program, optical fiber sensors were demonstrated for the measurement of temperature, pressure, flow, and acoustic waves, including three successful field tests in the Chevron/Texaco oil fields in Coalinga, California, and at the world-class oil flow simulation facilities in Tulsa, Oklahoma. Research efforts included the design and fabrication of sensor probes, development of signal processing algorithms, construction of test systems, development and testing of strategies for the protection of optical fibers and sensors in the downhole environment, development of remote monitoring capabilities allowing real-time monitoring of the field test data from virtually anywhere in the world, and development of novel data processing techniques. Comprehensive testing was performed to …
Date: June 1, 2003
Creator: Wang, Anbo; Cooper, Kristie L. & Pickrell, Gary R.
Partner: UNT Libraries Government Documents Department
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Neutron Detection with a Cryogenic Spectrometer

Description: Cryogenic calorimeters are used for x-ray detection because of their exquisite energy resolution and have found application in x-ray astronomy, and the search for dark matter. These devices operate by detecting the heat pulse produced by ionization in an absorber cooled to temperatures below 1 K. Such temperatures are needed to lower the absorber's heat capacity to the point that the deposition of even a few eV results in a measurable temperature excursion. Typical absorbers for dark matter measurements are massive Si or Ge crystals, and, with Ge, have achieved a resolution of 650 eV at 10 keV. Chow, et al., report the measurement of the 60 keV emission from {sup 241}Am with 230 eV resolution using a superconducting tin absorber. Cunningham, et al., also using a superconducting tin absorber, have recently reported a four-fold improvement over Chow. With such results being reported from the x- and gamma-ray world it is natural to examine the possibilities for cryogenic neutron spectroscopy. Such a detector would operate by detecting the heat pulses caused by neutron capture and scattering. To date, {sup 6}LiF has been the absorber of choice because relatively large crystals can be grown, and it is an insulating material with low heat capacity. Silver reports the fabrication of a {sup 6}LiF spectrometer operating at 328 mK and achieving a resolution of 39 keV. De Marcillac reports the fabrication of a spectrometer operating at 80 mK and achieving 16 keV resolution when bombarded with 5 MeV alpha particles. In this paper, we report preliminary results with a TiB{sub 2} absorber exposed to thermal neutrons. In contrast to lithium, whose chemistry selects for LiF as the absorber, boron offers a rich chemistry from which to select materials with high boron content. We will discuss the considerations governing the choice of absorber material …
Date: June 23, 2003
Creator: Bell, Z. W.; Lamberti, V. E.; Carpenter, D. A. & Cristy, S. S.
Partner: UNT Libraries Government Documents Department
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Physical Property Models of Concentrated Cesium Eluate Solutions

Description: Major analytes expected to be present in the WTP cesium ion-exchange eluate solutions were identified from the available analytical data collected during radioactive bench-scale runs, and a test matrix of cesium eluate solutions was designed within the bounding concentration ranges of those major analytes. A computer model describing the semi-batch evaporation of cesium eluate solutions was built using the Environmental Simulation Program (ESP), licensed by OLI Systems, Inc., and was run to calculate the physical properties of each test matrix solution concentrated to the target endpoints of 80 percent and 100 percent bulk saturation. The calculated physical properties were then analyzed statistically and fitted into predetermined mathematical expressions for the bulk solubility, density, viscosity and heat capacity as a function of temperature and feed concentration of each species considered in the matrix. In addition, the volume reduction factor, which is defined as the ratio of total cumulative feed volume to that of the initial acid charge, was calculated and modeled for the 80 percent saturation case. The R2 of the resulting physical property models ranged from 0.89 to 0.99. Validation of these physical property models against the true experimental data was not part of the current work scope; instead, the results of model validation will be discussed later in another report, after all the necessary data for model validation have been collected and analyzed.
Date: June 18, 2003
Creator: Choi, A.S.
Partner: UNT Libraries Government Documents Department
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RESOURCE CHARACTERIZATION AND QUANTIFICATION OF NATURAL GAS-HYDRATE AND ASSOCIATED FREE-GAS ACCUMULATIONS IN THE PRUDHOE BAY - KUPARUK RIVER AREA ON THE NORTH SLOPE OF ALASKA

Description: Interim results are presented from the project designed to characterize, quantify, and determine the commercial feasibility of Alaska North Slope (ANS) gas-hydrate and associated free-gas resources in the Prudhoe Bay Unit (PBU), Kuparuk River Unit (KRU), and Milne Point Unit (MPU) areas. This collaborative research will provide practical input to reservoir and economic models, determine the technical feasibility of gas hydrate production, and influence future exploration and field extension of this potential ANS resource. The large magnitude of unconventional in-place gas (40-100 TCF) and conventional ANS gas commercialization evaluation creates industry-DOE alignment to assess this potential resource. This region uniquely combines known gas hydrate presence and existing production infrastructure. Many technical, economical, environmental, and safety issues require resolution before enabling gas hydrate commercial production. Gas hydrate energy resource potential has been studied for nearly three decades. However, this knowledge has not been applied to practical ANS gas hydrate resource development. ANS gas hydrate and associated free gas reservoirs are being studied to determine reservoir extent, stratigraphy, structure, continuity, quality, variability, and geophysical and petrophysical property distribution. Phase 1 will characterize reservoirs, lead to recoverable reserve and commercial potential estimates, and define procedures for gas hydrate drilling, data acquisition, completion, and production. Phases 2 and 3 will integrate well, core, log, and long-term production test data from additional wells, if justified by results from prior phases. The project could lead to future ANS gas hydrate pilot development. This project will help solve technical and economic issues to enable government and industry to make informed decisions regarding future commercialization of unconventional gas-hydrate resources.
Date: June 2, 2003
Creator: Hunter, Robert; Patil, Shirish; Casavant, Robert & Collett, Tim
Partner: UNT Libraries Government Documents Department
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Sludge Batch 3 Simulant Flowsheet Studies: Phase II SRAT/SME Results

Description: The Savannah River Technology Center (SRTC) - Immobilization Technology Section (ITS) was requested to perform simulant bench-scale flowsheet studies to qualify Sludge Batch 3 (SB3), the next sludge batch to be processed at the Defense Waste Processing Facility (DWPF). Simulant flowsheet runs have been performed for every sludge batch that has been qualified for DWPF processing to date. SB3 will consist primarily of Tank 7 sludge, but will also contain transfers from other tanks and processes at the SRS and other materials not considered typical for DWPF processing. Projections also indicate that SB3 may contain higher than previously observed levels of noble metals. Over the last year, SRTC has focused significant effort on studies to understand the behavior of SB3 and to evaluate any necessary process changes.
Date: June 17, 2003
Creator: Herman, C. C.
Partner: UNT Libraries Government Documents Department
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Implementing 10 CFR 830 at the FEMP Silos: Nuclear Health and Safety Plans as Documented Safety Analysis

Description: The objective of the Silos Project at the Fernald Closure Project (FCP) is to safely remediate high-grade uranium ore residues (Silos 1 and 2) and metal oxide residues (Silo 3). The evolution of Documented Safety Analyses (DSAs) for these facilities has reflected the changes in remediation processes. The final stage in silos DSAs is an interpretation of 10 CFR 830 Safe Harbor Requirements that combines a Health and Safety Plan with nuclear safety requirements. This paper will address the development of a Nuclear Health and Safety Plan, or N-HASP.
Date: June 1, 2003
Creator: Fisk, Patricia & Rutherford, Lavon
Partner: UNT Libraries Government Documents Department
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CH Packaging Operations Manual

Description: Introduction - This procedure provides instructions for assembling the following CH packaging payload: -Drum payload assembly -Standard Waste Box (SWB) assembly -Ten-Drum Overpack (TDOP).
Date: June 26, 2003
Creator: Westinghouse TRU Solutions LLC
Partner: UNT Libraries Government Documents Department
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Reduction of the Radiotoxicity of Spent Nuclear Fuel Using a Two-Tiered System Comprising Light Water Reactors and Accelerator-Driven Systems

Description: Two main issues regarding the disposal of spent nuclear fuel from nuclear reactors in the United States in the geological repository Yucca Mountain are: (1) Yucca Mountain is not designed to hold the amount of fuel that has been and is proposed to be generated in the next few decades, and (2) the radiotoxicity (i.e., biological hazard) of the waste (particularly the actinides) does not decrease below that of natural uranium ore for hundreds of thousands of years. One solution to these problems may be to use transmutation to convert the nuclides in spent nuclear fuel to ones with shorter half-lives. Both reactor and accelerator-based systems have been examined in the past for transmutation; there are advantages and disadvantages associated with each. By using existing Light Water Reactors (LWRs) to burn a majority of the plutonium in spent nuclear fuel and Accelerator-Driven Systems (ADSs) to transmute the remainder of the actinides, the benefits of each type of system can be realized. The transmutation process then becomes more efficient and less expensive. This research searched for the best combination of LWRs with multiple recycling of plutonium and ADSs to transmute spent nuclear fuel from past and projected nuclear activities (assuming little growth of nuclear energy). The neutronic design of each system is examined in detail although thermal hydraulic performance would have to be considered before a final system is designed. The results are obtained using the Monte Carlo burnup code Monteburns, which has been successfully benchmarked for MOX fuel irradiation and compared to other codes for ADS calculations. The best combination of systems found in this research includes 41 LWRs burning mixed oxide fuel with two recycles of plutonium ({approx}40 years operation each) and 53 ADSs to transmute the remainder of the actinides from spent nuclear fuel over the course of …
Date: June 1, 2003
Creator: Trellue, H.R.
Partner: UNT Libraries Government Documents Department
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