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[Group holding Verizon's check to TAMS program]

Description: A photograph of (L-R) Dr. Norval Pohl, the President of UNT, Mary Jane Johnston, the President of Verizon's Texas Region, Revathi Ravi, a TAMS student, and Dr. Richard Sinclair, the Dean of the TAMS program. They are all holding up a check from Verizon to the TAMS program that is worth $50,000. Behind them is a plaque for the President's Council lifetime members.
Date: April 1, 2003
Creator: University of North Texas. Center for Media Production.
Partner: UNT Libraries Special Collections
open access

[Hartman Award Copy by Fred B. Hartman]

Description: A document describing the origins of the Fred Hartman award to be used when presenting the award to those deserving of it. The Fred Hartman Excellence in Sportswriting Award was established after Fred Hartman's death in 1991 by his son, daughter and wife as Fred Hartman loved sports.
Date: March 1, 2003
Creator: Texas Daily Newspaper Association
Partner: UNT Libraries Special Collections
open access

[Hartman Award Copy by Fred B. Hartman, 2]

Description: A document describing the origins of the Fred Hartman award to be used when presenting the award to those deserving of it. The Fred Hartman Excellence in Sportswriting Award was established after Fred Hartman's death in 1991 by his son, daughter and wife as Fred Hartman loved sports.
Date: March 1, 2003
Creator: Texas Daily Newspaper Association
Partner: UNT Libraries Special Collections
open access

Reconnaissance of Field Sites for the Study of Chemical Weathering on the Guayana Shield, South America

Description: Despite the fact that chemical weathering of silicate rocks plays an important role in the draw-down of CO{sub 2} over geologic time scales (Berner and Berner, 1996), the overall controls on the rate of chemical weathering are still not completely understood. Lacking a mechanistic understanding of these controls, it remains difficult to evaluate a hypothesis such as that presented by Raymo and Ruddiman (1992), who suggested that enhanced weathering and CO{sub 2} draw-down resulting from the uplift of the Himalayas contributed to global cooling during the Cenozoic. At an even more fundamental level, the three to four order of magnitude discrepancy between laboratory and field weathering rates is still unresolved (White et al., 1996). There is as yet no comprehensive, mechanistic model for silicate chemical weathering that considers the coupled effects of precipitation, vadose zone flow, and chemical reactions. The absence of robust process models for silicate weathering and the failure to resolve some of these important questions may in fact be related-the controls on the overall rates of weathering cannot be understood without considering the weathering environment as one in which multiple, time-dependent chemical and physical processes are coupled (Malmstrom, 2000). Once chemical weathering is understood at a mechanistic process level, the important controls on chemical weathering (physical erosion, temperature, precipitation) can be folded into larger scale models tracking the global carbon cycle. Our goal in this study was to carry out the preliminary work needed to establish a field research site for chemical weathering om the Cuayana Shield in South America. The Guayana Shield is a Precambrian province greater than 1.5 billion years old covering portions of Venezuela, Guyana (the country), Surinam, French Guiana, and Brazil (Figure 1). More important than the age of the rocks themselves, however, is the age of the erosion surface developed on the …
Date: February 1, 2003
Creator: Steefell, C. I.; Viani, B. E.; Ramirez, A. & Lee, K.
Partner: UNT Libraries Government Documents Department
open access

Physical evidence for dark energy

Description: The authors present measurements of the angular cross-correlation between luminous red galaxies from the Sloan Digital Sky Survey and the cosmic microwave background temperature maps from the Wilkinson Microwave Anisotropy Probe. They find a statistically significant achromatic positive correlation between these two data sets, which is consistent with the expected signal from the late Integrated Sachs-Wolfe (ISW) effect. they do not detect any anti-correlation on small angular scales as would be produced from a large Sunyaev-Zel'dovich (SZ) effect, although they do see evidence for some SZ effect for their highest redshift samples. Assuming a flat universe, their preliminary detection of the ISW effect provides independent physical evidence for the existence of dark energy.
Date: July 1, 2003
Creator: Scranton, Ryan; Connolly, Andrew J.; Nichol, Robert C.; Stebbins, Albert; Szapudi, Istvan; Eisenstein, Daniel J. et al.
Partner: UNT Libraries Government Documents Department
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Microstructure of Surface Layers in Cu(In,Ga)Se2 Thin Films

Description: In most Cu(In,Ga)Se2 thin films used for solar cells, there usually exist interfaces lying about 0.1 to 0.2 m below the surfaces. We report on a convergent-beam electron diffraction and energy-dispersive X-ray spectroscopy study of the microstructure and chemical composition of the surface region in Cu(In,Ga)Se2 thin films. We find that the surface region and the bulk are structurally similar, with no ordered defect chalcopyrite structure observed. However, their composition is slightly different, indicating that they can have different point-defect physics. Our results suggest that the subinterfaces and the bulk absorber may form homojunctions.
Date: May 1, 2003
Creator: Yan, Y.; Jones, K. M.; AbuShama, J.; Young, M.; Asher, S.; Al-Jassim, M. M. et al.
Partner: UNT Libraries Government Documents Department
open access

12th Workshop on Crystalline Silicon Solar Cell Materials and Processes: Summary Discussion Sessions

Description: This report is a summary of the discussion sessions of the 12th Workshop on Crystalline Silicon Solar Cells and Processes. The theme of the workshop was"Fundamental R&D in c-Si: Enabling Progress in Solar-Electric Technology." This theme was chosen to reflect a concern that the current expansion in the PV energy production may redirect basic research efforts to production-oriented issues. The PV industry is installing added production capacity and new production lines that include the latest technologies. Once the technologies are selected, it is difficult to make changes. Consequently, a large expansion can stagnate the technologies and diminish interest in fundamental research. To prevent the fundamental R&D program from being overwhelmed by the desire to address immediate engineering issues, there is a need to establish topics of fundamental nature that can be pursued by the universities and the research institutions. Hence, one of the objectives of the workshop was to identify such areas for fundamental research.
Date: February 1, 2003
Creator: Sopori, B.; Swanson, D.; Sinton, R. & Tan, T.
Partner: UNT Libraries Government Documents Department
open access

Positronium in Solids: Computer Simulation of Pick-Off and Self-Annihilation

Description: Positronium (Ps) is simulated using Path Integral Monte Carlo (PIMC). This method can reproduce the results of previous simple theories in which a single quantum particle is used to represent Ps within an idealized pore. In addition, the calculations treat the e{sup -} and e{sup +} of Ps exactly and realistically model interactions with solid atoms, thereby correcting and extending the simpler theory. They study the pick-off lifetime of o-Ps and the internal contact density, {kappa}, which controls the self-annihilation behavior, for Ps in model voids (spherical pores), defects in a solid (argon), and microporous solids (zeolites).
Date: August 1, 2003
Creator: Bug, A.; Muluneh, M.; Waldman, J. & Sterne, P.
Partner: UNT Libraries Government Documents Department
open access

Building a Bridge to the Ethanol Industry--Follow-up Project: Period of Performance; February 22, 2001- December 31, 2002

Description: Subcontract report summarizing results of a trial of a corn fiber pretreatment process. The results of the trial showed that the carbohydrates in the pretreated liquid and solid streams are readily hydrolyzed by enzymes and easily fermentable to ethanol by yeast.
Date: April 1, 2003
Creator: Ladisch, M.; Mosier, N.; Welch, G. & Dien, B.
Partner: UNT Libraries Government Documents Department
open access

NSLS 2002 ACTIVITY REPORT (NATIONAL SYNCHROTRON LIGHT SOURCE ACTIVITY REPORT 2002).

Description: The year 2002 has been another highly productive year at the NSLS and an impressive array of highlights from this scientific activity is included in this Activity Report. They have taken significant steps this past year toward better supporting beamlines and users. The number of user science support staff has been increased by about ten positions. They have also worked with their users, DOE, and the other DOE synchrotron facilities to develop a new, more flexible user access policy. Doing things safely remains a top priority, and they are reviewing their training and safety requirements to ensure they are thorough and everyone fully understands the necessity of abiding by them. A major development this past year was approval from DOE for BNL to begin the conceptual design of the Center for Functional Nanomaterials (CFN). The CFN will have a dramatic impact on nanoscience in the Northeast, facilitating the synthesis, characterization and scientific exploration of new classes of novel nanostructured materials. It will be located adjacent to the NSLS and a number of NSLS beamlines will be optimized to serve the needs of the nanoscience community. The NSLS and CFN user programs will be coordinated to facilitate easy access to both in a single visit. The VUV and X-Ray rings operated with excellent reliability as a result of continued attention to aging critical systems. The DUV-FEL achieved several important milestones this year, including production of Self-Amplified Spontaneous Emission (SASE) laser light at 400 nm and 266 nm, laser seeded saturation at 266 nm, and the first observation of High Gain Harmonic Generation (HGHG) light at 266 nm, with a third harmonic at 89 nm. Light from the DUV-FEL is now enabling user science experiments in ion pair imaging and they look forward to an expanding user program and a continued series …
Date: May 1, 2003
Creator: Miller, L.
Partner: UNT Libraries Government Documents Department
open access

Technologies for Fissile Material Detection and Prevention of Fissile Material Introduction into International Shipping

Description: Prevention of the introduction of fissile materials into international shipping, and hence into a given country, is a complex problem. Some pieces of the solution to the puzzle are conceptually well defined, but lack definition of a technical pathway and/or operational implementation. Other elements are a little more fuzzy, and some elements are probably undefined at this point in time. This paper reviews the status of the more well-defined elements, and suggests needed additional measures to enhance the probability that fissile materials are not illicitly introduced into distant countries. International commerce proceeds through a number of steps from point of origin to final destination. Each step offers the possibility of a well-defined choke point to monitor and interdict the illicit shipment of fissile materials. However, because there are so many potential points and venues of entry into a large country such as the United States (e.g., air cargo, shipping containers, truck and rail transport, private vehicles, boats and planes, commercial passenger travel), it behooves the world to ensure that fissile material does not illicitly leave its point of origin.
Date: July 1, 2003
Creator: Richardson, J
Partner: UNT Libraries Government Documents Department
open access

Acoustic Propagation in a Water-Filled Cylindrical Pipe

Description: This study was concerned with the physics of the propagation of a tone burst of high frequency sound in a steel water-filled pipe. The choice of the pulse was rather arbitrary, so that this work in no way can be considered as recommending a particular pulse form. However, the MATLAB computer codes developed in this study are general enough to carry out studies of pulses of various forms. Also, it should be pointed out that the codes as written are quite time consuming. A computation of the complete field, including all 5995 modes, requires several hours on a desktop computer. The time required by such computations as these is a direct consequence of the bandwidths, frequencies and sample rates employed. No attempt was made to optimize these codes, and it is assumed that much can be done in this regard.
Date: June 1, 2003
Creator: Sullivan, E. J. & Candy, J. V.
Partner: UNT Libraries Government Documents Department
open access

Gas Generation from K East Basin Sludges and Irradiated Metallic Uranium Fuel Particles Series III Testing

Description: The path forward for managing of Hanford K Basin sludge calls for it to be packaged, shipped, and stored at T Plant until final processing at a future date. An important consideration for the design and cost of retrieval, transportation, and storage systems is the potential for heat and gas generation through oxidation reactions between uranium metal and water. This report, the third in a series (Series III), describes work performed at the Pacific Northwest National Laboratory (PNNL) to assess corrosion and gas generation from irradiated metallic uranium particles (fuel particles) with and without K Basin sludge addition. The testing described in this report consisted of 12 tests. In 10 of the tests, 4.3 to 26.4 g of fuel particles of selected size distribution were placed into 60- or 800-ml reaction vessels with 0 to 100 g settled sludge. In another test, a single 3.72-g fuel fragment (i.e., 7150-mm particle) was placed in a 60 ml reaction vessel with no added sludge. The twelfth test contained only sludge. The fuel particles were prepared by crushing archived coupons (samples) from an irradiated metallic uranium fuel element. After loading the sludge materials (whether fuel particles, mixtures of fuel particles and sludge, or sludge-only) into reaction vessels, the solids were covered with an excess of K Basin water, the vessels closed and connected to a gas measurement manifold, and the vessels back-flushed with inert neon cover gas. The vessels were then heated to a constant temperature. The gas pressures and temperatures were monitored continuously from the times the vessels were purged. Gas samples were collected at various times during the tests, and the samples analyzed by mass spectrometry. Data on the reaction rates of uranium metal fuel particles with water as a function of temperature and particle size were generated. The data were …
Date: August 1, 2003
Creator: Schmidt, Andrew J.; Delegard, Calvin H.; Bryan, Samuel A.; Elmore, Monte R.; Sell, Rachel L.; Silvers, Kurt L. et al.
Partner: UNT Libraries Government Documents Department
open access

RadSensor: Xray Detection by Direct Modulation of an Optical Probe Beam

Description: We present a new x-ray detection technique based on optical measurement of the effects of x-ray absorption and electron hole pair creation in a direct band-gap semiconductor. The electron-hole pairs create a frequency dependent shift in optical refractive index and absorption. This is sensed by simultaneously directing an optical carrier beam through the same volume of semiconducting medium that has experienced an xray induced modulation in the electron-hole population. If the operating wavelength of the optical carrier beam is chosen to be close to the semiconductor band-edge, the optical carrier will be modulated significantly in phase and amplitude. This approach should be simultaneously capable of very high sensitivity and excellent temporal response, even in the difficult high-energy xray regime. At xray photon energies near 10 keV and higher, we believe that sub-picosecond temporal responses are possible with near single xray photon sensitivity. The approach also allows for the convenient and EMI robust transport of high-bandwidth information via fiber optics. Furthermore, the technology can be scaled to imaging applications. The basic physics of the detector, implementation considerations, and preliminary experimental data are presented and discussed.
Date: August 1, 2003
Creator: Lowry, M. E.; Bennett, C. V.; Vernon, S. P.; Bond, T.; Welty, R.; Behymer, E. et al.
Partner: UNT Libraries Government Documents Department
open access

Report on LCI Database Project Meeting of Interests; Period of Performance: May 7, 2001--December 1, 2001

Description: This is a report of the Meeting of Interests for the Life-cycle Inventory (LCI) Database Project hosted by the Ford Motor Company. The meeting was held to explain the project, discuss related issues and concerns, and to seek the support of a broad spectrum of relevant organizations. The ultimate goal of the project is to develop publicly available LCI Data modules for commonly used materials, products, and processes.
Date: August 1, 2003
Partner: UNT Libraries Government Documents Department
open access

Laser Science and Technology Program Annual Report-2002 NIF Programs Directorate

Description: The Laser Science and Technology (LS&T) Program's mission is to develop advanced lasers, optics, materials technologies, and applications to solve problems and create new capabilities of importance to the nation and the Laboratory. A top, near-term priority is to provide technical support in the deployment and upgrade of the National Ignition Facility (NIF). Our other program activities synergistically develop technologies that are consistent with the goals of the NIF Directorate and develop state-of-the-art capabilities. The primary objectives of LS&T activities in 2002 have been fourfold--(a) to support deployment of hardware and to enhance laser and optics performance for NIF, (b) to develop high-energy petawatt laser science and technology for the Department of Energy (DOE), (c) to develop advanced solid-state laser systems and optical components for the Department of Defense (DoD), and (d) to invent, develop, and deliver improved concepts and hardware for other government agencies and industry. LS&T activities during 2002 focused on seven major areas: (1) NIF Project-LS&T led major advances in the deployment of NIF Final Optics Assembly (FOA) and the development of 30.1 optics processing and treatment technologies to enhance NIF's operations and performance capabilities. (2) Stockpile Stewardship Program (SSP)-LS&T personnel continued development of ultrashort-pulse lasers and high-power, large-aperture optics for applications in SSP, extreme-field science and national defense. To enhance the high-energy petawatt (HEPW) capability in NIF, LS&T continued development of advanced compressor-grating and front-end laser technologies utilizing optical-parametric chirped-pulse amplification (OPCPA). (3) High-energy-density physics and inertial fusion energy-LS&T continued development of kW- to MW-class, diode-pumped, solid-state laser (DPSSL). (4) Department of Defense (DoD)-LS&T continued development of a 100 kw-class solid-state heat-capacity laser (SSHCL) for missile defense. (5) Nuclear energy applications-LS&T continued to develop laser-shock peening technology to improve the service lifetime of metal nuclear waste containment canisters designed for DOES Yucca Mountain Project. (6) Materials …
Date: March 1, 2003
Creator: Hackel, L. & Chen, H. L.
Partner: UNT Libraries Government Documents Department
open access

Rohm and Haas: Company Uses Knoxville Plant Assessment Results to Develop Best Practices Guidelines and Benchmark for Its Other Sites (Revised)

Description: Rohm and Haas conducted a plant-wide energy assessment at its Knoxville, Tennessee, chemicals manufacturing facility. The assessment identified potential annual energy savings of nearly 47,000 MMBtu in steam and fuel and 11,000 MWh in electricity. Annual cost savings were estimated at almost$1.5 million. After the assessment was replicated in California and Kentucky plants, the companys additional estimated cost savings were$500,000 annually. Additional annual energy savings were about 23,000 MMBtu and 6,000 MWh. The assessments also indicated the plants would reduce nitrous oxide emissions.
Date: July 1, 2003
Partner: UNT Libraries Government Documents Department
open access

Photovoltaic Module Thermal/Wind Performance: Long-Term Monitoring and Model Development for Energy Rating

Description: In order to predict the energy production of photovoltaic (PV) modules, it is necessary to predict the module temperature as a function of ambient temperature, wind speed, wind direction, total irradiance, and relative humidity. This paper presents a mathematical model to predict the module temperature based on the field monitored real data of module temperature, ambient temperature, wind speed, wind direction and relative humidity.
Date: June 1, 2003
Creator: TamizhMani, G.; Ji, L.; Tang, Y.; Petacci, L. & Osterwald, C.
Partner: UNT Libraries Government Documents Department
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Advanced Simulation and Computing: A Summary Report to the Director's Review

Description: It has now been three years since the Advanced Simulation and Computing Program (ASCI), as managed by Defense and Nuclear Technologies (DNT) Directorate, has been reviewed by this Director's Review Committee (DRC). Since that time, there has been considerable progress for all components of the ASCI Program, and these developments will be highlighted in this document and in the presentations planned for June 9 and 10, 2003. There have also been some name changes. Today, the Program is called ''Advanced Simulation and Computing,'' Although it retains the familiar acronym ASCI, the initiative nature of the effort has given way to sustained services as an integral part of the Stockpile Stewardship Program (SSP). All computing efforts at LLNL and the other two Defense Program (DP) laboratories are funded and managed under ASCI. This includes the so-called legacy codes, which remain essential tools in stockpile stewardship. The contract between the Department of Energy (DOE) and the University of California (UC) specifies an independent appraisal of Directorate technical work and programmatic management. Such represents the work of this DNT Review Committee. Beginning this year, the Laboratory is implementing a new review system. This process was negotiated between UC, the National Nuclear Security Administration (NNSA), and the Laboratory Directors. Central to this approach are eight performance objectives that focus on key programmatic and administrative goals. Associated with each of these objectives are a number of performance measures to more clearly characterize the attainment of the objectives. Each performance measure has a lead directorate and one or more contributing directorates. Each measure has an evaluation plan and has identified expected documentation to be included in the ''Assessment File''.
Date: June 1, 2003
Creator: McCoy, M G & Peck, T
Partner: UNT Libraries Government Documents Department
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