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  Partner: UNT Libraries Government Documents Department
 Decade: 2000-2009
 Language: English
The 0.22 Percent Across-the-Board Cut in FY2001 Appropriations

The 0.22 Percent Across-the-Board Cut in FY2001 Appropriations

Date: May 31, 2001
Creator: Keith, Robert
Description: Report describing changes that affected the government budget for the 2001 fiscal year under the Consolidated Appropriations Act.
Contributing Partner: UNT Libraries Government Documents Department
The 0.38 Percent Across-the-Board Cut in FY2000 Appropriations

The 0.38 Percent Across-the-Board Cut in FY2000 Appropriations

Date: February 25, 2000
Creator: Keith, Robert
Description: This report outlines cuts made in the federal budget for FY2000. The 0.38% cut was expected to yield savings of $2.4 billion in budget authority and $1.4 billion in outlays for the fiscal year. Departments with cuts in excess of $100 million included the Departments of Defense, Transportation, Health and Human Services, and Education.
Contributing Partner: UNT Libraries Government Documents Department
0.52eV Quaternary InGaAsSb Thermophotovoltaic Diode Technology

0.52eV Quaternary InGaAsSb Thermophotovoltaic Diode Technology

Date: June 9, 2004
Creator: Dashiell, M. W.; Beausang, J. F.; Nichols, G.; Depoy, D. M.; Danielson, L. R.; Ehsani, H. et al.
Description: Thermophotovoltaic (TPV) diodes fabricated from 0.52eV lattice-matched InGaAsSb alloys are grown by Metal Organic Vapor Phase Epitaxy (MOVPE) on GaSb substrates. 4cm{sup 2} multi-chip diode modules with front-surface spectral filters were tested in a vacuum cavity and attained measured efficiency and power density of 19% and 0.58 W/cm{sup 2} respectively at operating at temperatures of T{sub radiator} = 950 C and T{sub diode} = 27 C. Device modeling and minority carrier lifetime measurements of double heterostructure lifetime specimens indicate that diode conversion efficiency is limited predominantly by interface recombination and photon energy loss to the GaSb substrate and back ohmic contact. Recent improvements to the diode include lattice-matched p-type AlGaAsSb passivating layers with interface recombination velocities less than 100 cm/s and new processing techniques enabling thinned substrates and back surface reflectors. Modeling predictions of these improvements to the diode architecture indicate that conversion efficiencies from 27-30% and {approx}0.85 W/cm{sup 2} could be attained under the above operating temperatures.
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1,3-Propanediol Made From Fermentation-Derived Malonic Acid: Office of Industrial Technologies (OIT) Agriculture Project Fact Sheet

1,3-Propanediol Made From Fermentation-Derived Malonic Acid: Office of Industrial Technologies (OIT) Agriculture Project Fact Sheet

Date: September 12, 2001
Creator: Carde, T.
Description: 1,3-Propanediol is one of two ingredients used in producing polytrimethylene terephthalate (PTT), a polymer which can be used in polyester and nylon applications. Researchers are developing a process to ferment biomass feedstock to malonic acid using filamentous fungi and then catalytically convert malonic acid to 1,3-propanediol.
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1.5-GeV FFAG Accelerator for the AGS Facility

1.5-GeV FFAG Accelerator for the AGS Facility

Date: February 1, 2004
Creator: Ruggiero, A. G.; Blaskiewicz, M.; Courant, E.; Trbojevic, D.; Tsoupas, N. & Zhang, W.
Description: N/A
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A 1.8 Mev K+ injector for the high current beam transport experiment fusion

A 1.8 Mev K+ injector for the high current beam transport experiment fusion

Date: May 20, 2002
Creator: Kwan, J.W.; Bieniosek,F.M.; Henestroza, E.; Prost, L. & Seidl, P.
Description: For the High Current Beam Transport Experiment (HCX) at LBNL, an injector is required to deliver up to 1.8 MV of 0.6 A K{sup +} beam with an emittance of {approx}1 p-mm-mrad. We have successfully operated a 10-cm diameter surface ionization source together with an electrostatic quadrupole (ESQ) accelerator to meet these requirements. The pulse length is {approx}4 {micro}s, firing at once every 10-15 seconds. By optimizing the extraction diode and the ESQ voltages, we have obtained an output beam with good current density uniformity, except for a small increase near the beam edge. Characterization of the beam emerging from the injector included measurements of the intensity profile, beam imaging, and transverse phase space. These data along with comparison to computer simulations provide the knowledge base for designing and understanding future HCX experiments.
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1-D EQUILIBRIUM DISCRETE DIFFUSION MONTE CARLO

1-D EQUILIBRIUM DISCRETE DIFFUSION MONTE CARLO

Date: August 2000
Creator: Evans, T. M.; Urbatsch, T. J. & Lichtenstein, H.
Description: We present a new hybrid Monte Carlo method for 1-D equilibrium diffusion problems in which the radiation field coexists with matter in local thermodynamic equilibrium. This method, the Equilibrium Discrete Diffusion Monte Carlo (EqDDMC) method, combines Monte Carlo particles with spatially discrete diffusion solutions. We verify the EqDDMC method with computational results from three slab problems. The EqDDMC method represents an incremental step toward applying this hybrid methodology to non-equilibrium diffusion, where it could be simultaneously coupled to Monte Carlo transport.
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A 1 MEGAWATT POLYPHASE BOOST CONVERTER-MODULATOR FOR KLYSTRON PULSE APPLICATION

A 1 MEGAWATT POLYPHASE BOOST CONVERTER-MODULATOR FOR KLYSTRON PULSE APPLICATION

Date: June 1, 2001
Creator: REASS, W.A.; DOSS, J.D. & GRIBBLE, R.F.
Description: This paper describes electrical design criteria and first operational results a 140 kV, 1 MW average, 11 MW peak, zero-voltage-switching 20 kHz polyphase bridge, boost converter/modulator for klystron pulse application. The DC-DC converter derives the buss voltages from a standard 13.8 kV to 2300 Y substation cast-core transformer. Energy storage and filtering is provided by self-clearing metallized hazy polypropylene traction capacitors. Three ''H-Bridge'' Insulated Gate Bipolar Transistor (IGBT) switching networks are used to generate the polyphase 20 kHz transformer primary drive waveforms. The 20 kHz drive waveforms are chirped the appropriate duration to generate the desired klystron pulse width. PWM (pulse width modulation) of the individual 20 kHz pulses is utilized to provide regulated output waveforms with adaptive feedforward and feedback techniques. The boost transformer design utilizes amorphous nanocrystalline material that provides the required low core loss at design flux levels and switching frequencies. Resonant shunt-peaking is used on the transformer secondary to boost output voltage and resonate transformer leakage inductance. With the appropriate transformer leakage inductance and peaking capacitance, zero-voltage-switching of the IGBT's is attained, minimizing switching losses. A review of these design parameters and the first results of the performance characteristics will be presented.
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1 Outreach, Education and Domestic Market Enhancement 2 Export Promotion and Assistance

1 Outreach, Education and Domestic Market Enhancement 2 Export Promotion and Assistance

Date: March 15, 2004
Creator: Geothermal Energy Association
Description: Geothermal Energy Association supports the US geothermal industry in its efforts to bring more clean geothermal energy on-line throughout the world. Activities designed to accomplish this goal include: (1) developing and maintaining data bases, web pages, (2) commissioning of special studies and reports, (3) preparing, printing and distributing brochures and newsletters, (4) developing exhibits and displays, and participating in trade shows, (5) designing, producing and disseminating audio-video materials, (6) monitoring and coordinating programs carried out by US DOE and other Federal agencies, (7) holding workshops to facilitate communication between researchers and industry and to encourage their recognition of emerging markets for geothermal technology, (8) attending conferences, making speeches and presentation, and otherwise interacting with environmental and other renewable energy organizations and coalitions, (9) hosting events in Washington, DC and other appropriate locations to educate Federal, State and local representatives, environmental groups, the news media, and other about the status and potential of geothermal energy, (10) conducting member services such as the preparation and distribution of a member newsletter related to operating and maintaining s useful and viable association, and (11) performing similar kinds of activities designed to inform others about geothermal energy. The activities of the export promotion aim to ...
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2.5 MHz feedforward beam loading compensation in the Fermilab Main Injector

2.5 MHz feedforward beam loading compensation in the Fermilab Main Injector

Date: May 19, 2003
Creator: Dey, Joseph E.; Kourbanis, Ioanis & Steimel, James
Description: There are five 2.5 MHz ferrite cavities (h = 28) in the Main Injector with an R/Q of 500 that are presently used for coalescing for the Tevatron. For use with the Fermilab Recycler, feedforward (FF) beam loading compensation (BLC) is required on these cavities because they will be required to operate at a net of 2 kV. Under current Recycler beam conditions, the beam-induced voltage is of this order. Recently a system using a digital bucket delay module operating at 53 MHz (h = 588) was used to produce a one-turn-delay feedforward signal. This signal was then combined with the low level RF signal to the 2.5 MHz cavities to cancel the beam induced voltage. During current operation they have shown consistently to operate with over a 20 dB reduction in beam loading.
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The 2.6 Angstrom resolution structure of Rhodobacter capsulatus bacterioferritin with metal-free dinuclear site and heme iron in a crystallographic 'special position'

The 2.6 Angstrom resolution structure of Rhodobacter capsulatus bacterioferritin with metal-free dinuclear site and heme iron in a crystallographic 'special position'

Date: October 31, 2001
Creator: Cobessi, D.; Huang, L.-S.; Ban, M.; Pon, N.G.; Daldal, F. & Berry, E.A.
Description: No abstract prepared.
Contributing Partner: UNT Libraries Government Documents Department
2-D and 3-D Elastic Modeling with Shared Seismic Models

2-D and 3-D Elastic Modeling with Shared Seismic Models

Date: April 30, 2002
Creator: House, L.; Marfurt, K. J.; Larsen, S. & Martin, G. S.
Description: Several elastic models, both 2-D and 3-D, are being built for use in calculating synthetic elastic seismic data. The models will be made available to the research community, along with the synthetic data that are being calculated from them. These shared models have been proposed or contributed by participants in a collaborative industry, national laboratory, and university research project. The purpose of the modeling is to provide synthetic data to better understand elastic wave propagation and the effects of structural and stratigraphic complexities. The 2-D models are easier to design and change and synthetic calculations can be run relatively quickly in them. It will be possible to alter their layer properties and calculate time-lapse data sets from them. Field data will be available to accompany many of the 2-D models. 3-D models are more realistic, but more difficult to design and change. They also require considerably more computing resources to calculate synthetic data from them. A new 3-D model is being designed, and will be used for computing synthetic elastic data.
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2-D Imaging of Electron Temperature in Tokamak Plasmas

2-D Imaging of Electron Temperature in Tokamak Plasmas

Date: July 8, 2004
Creator: Munsat, T.; Mazzucato, E.; Park, H.; Domier, C. W.; Johnson, M.; Luhmann, N. C., Jr. et al.
Description: By taking advantage of recent developments in millimeter wave imaging technology, an Electron Cyclotron Emission Imaging (ECEI) instrument, capable of simultaneously measuring 128 channels of localized electron temperature over a 2-D map in the poloidal plane, has been developed for the TEXTOR tokamak. Data from the new instrument, detailing the MHD activity associated with a sawtooth crash, is presented.
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A 2-D Pore-Network Model of the Drying of Single-Component Liquids in Porous Media

A 2-D Pore-Network Model of the Drying of Single-Component Liquids in Porous Media

Date: January 20, 2000
Creator: Yortsos, Yanic C.; Yiotis, A. G.; Stubos, A. K. & Boundovis, A. G.
Description: The drying of liquid-saturated porous media is typically approaching using macroscopic continuum models involving phenomenological coefficients. Insight on these coefficients can be obtained by a more fundamental study at the pore- and pore-network levels. In this report, a model based on pore-network representation of porous media that accounts for various process at the pore-scale is presented. These include mass transfer by advection and diffusion in the gas phase, viscous flow in liquid and gas phases and capillary effects at the gas-liquid menisci in the pore throats.
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2-D Simulations of Drainage Winds and Diffusion Compared to Observations

2-D Simulations of Drainage Winds and Diffusion Compared to Observations

Date: May 29, 2001
Creator: Garrett, A. J.
Description: A vertically integrated dynamical drainage flow model is developed from conservation equations for momentum and mass in a terrain-following coordinate system. Wind fields from the dynamical model drive a Monte Carlo transport and diffusion model. The model needs only topographic data, an Eulerian or Lagrangian time scale and a surface drag coefficient for input data, and can be started with a motionless atmosphere. Model wind and diffusion predictions are compared to observations from the rugged Geysers CA area. Model winds generally agree with observed surface winds, and in some cases may give better estimates of area-averaged flow than point observations. Tracer gas concentration contours agree qualitatively with observed contours, and point predictions of maximum concentrations were correctly predicted to within factors of 2 to 10. Standard statistical tests of model skill showed that the accuracy of the predictions varied significantly from canyon to canyon in the Geysers are a. Model wind predictions are also compared to observations from the Savannah River Plant of SC which has gently rolling terrain. The model correctly simulated the slower development of drainage winds and slower deepening of the drainage layer in the Savannah River Valley, relative to the Geysers CA simulations. The SC simulations ...
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2 Letters from concerned citizens in response to the recommendation regarding the Defense Office of Hearings and Appeals in Fort Meade

2 Letters from concerned citizens in response to the recommendation regarding the Defense Office of Hearings and Appeals in Fort Meade

Date: July 30, 2005
Creator: unknown
Description: Community Correspondence - 2 Letters from concerned citizens in response to the recommendation regarding the Defense Office of Hearings and Appeals in Fort Meade
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2-MV electrostatic quadrupole injector for heavy-ion fusion

2-MV electrostatic quadrupole injector for heavy-ion fusion

Date: November 10, 2004
Creator: Bieniosek, F.M.; Celata, C.M.; Henestroza, E.; Kwan, J.W.; Prost, L. & Seidl, P.A.
Description: High current and low emittance are principal requirements for heavy-ion injection into a linac driver for inertial fusion energy. An electrostatic quadrupole (ESQ) injector is capable of providing these high charge density and low emittance beams. We have modified the existing 2-MV Injector to reduce beam emittance and to double the pulse length. We characterize the beam delivered by the modified injector to the High Current Transport Experiment (HCX) and the effects of finite rise time of the extraction voltage pulse in the diode on the beam head. We demonstrate techniques for mitigating aberrations and reducing beam emittance growth in the injector.
Contributing Partner: UNT Libraries Government Documents Department
2 MW upgrade of the Fermilab Main Injector

2 MW upgrade of the Fermilab Main Injector

Date: June 4, 2003
Creator: Chou, Weiren
Description: In January 2002, the Fermilab Director initiated a design study for a high average power, modest energy proton facility. An intensity upgrade to Fermilab's 120-GeV Main Injector (MI) represents an attractive concept for such a facility, which would leverage existing beam lines and experimental areas and would greatly enhance physics opportunities at Fermilab and in the U.S. With a Proton Driver replacing the present Booster, the beam intensity of the MI is expected to be increased by a factor of five. Accompanied by a shorter cycle, the beam power would reach 2 MW. This would make the MI a more powerful machine than the SNS or the J-PARC. Moreover, the high beam energy (120 GeV) and tunable energy range (8-120 GeV) would make it a unique high power proton facility. The upgrade study has been completed and published. This paper gives a summary report.
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2-Page Summary for Neptunium solubility in the Near-field Environment of A Proposed Yucca Mountain Repository

2-Page Summary for Neptunium solubility in the Near-field Environment of A Proposed Yucca Mountain Repository

Date: March 29, 2005
Creator: Sassani, D.; van Luik, A. & Summerson, J.
Description: The total system performance assessment (TSPA) for the proposed repository at Yucca Mountain, NV, includes a wide variety of processes to evaluate the potential release of radionuclides from the Engineered Barrier System into the unsaturated zone of the geosphere. The principal processes controlling radionuclide release and mobilization from the waste forms are captured in the model to assess the dissolved concentrations of radionuclides in the source-term. The TSPA model of the source-term incorporates the far-from-equilibrium dissolution of, for example, spent nuclear fuel (SNF) to capture bounding rates of radionuclide availability as the SNF degrades. In addition, for individual radionuclides, the source-term model evaluates solubility constraints that are more indicative of longer-term, equilibrium processes that can limit the potential mass transport from the source term in those cases. These solubility limits represent phase saturation and precipitation processes that can occur either at the waste form as it alters, or at other locations in the near-field environment (e.g., within the invert) if chemical conditions are different. Identification and selection of applicable constraints for solubility-limited radionuclide concentrations is a primary focus in formulating the source-term model for the TSPA. Neptunium is a long-lived radionuclide that becomes a larger fraction of the potential dose ...
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2-pi Photoproduction from CLAS and CB-ELSA - The Search for Missing Resonances

2-pi Photoproduction from CLAS and CB-ELSA - The Search for Missing Resonances

Date: October 1, 2003
Creator: Thoma, Ulrike
Description: 2-pi-photoproduction is one of the promising reactions to search for baryon resonances that have been predicted but have not yet been observed. The gamma-rho --> rho-pi{sup 0}-pi{sup 0}(CB-ELSA) and the gamma-rho --> rho-pi{sup +}-pi{sup -} (CLAS) data show interesting resonance structures. A partial wave analysis (PWA) has to be done to determine which baryon resonances contribute what their quantum numbers and their relative couplings to the different accessible rho-2-pi-channels and to the photon are. First preliminary PWA-results on the lowest energy rho-pi{sup 0}-pi{sup 0} data (sq rt s<1.8 GeV)look very promising. From an extension of this analysis to higher energies combining the rho-pi{sup 0}-pi{sup 0} and the rho-pi{sup +}-pi{sup -}-data, one can expect; interesting results on resonances decaying into Delta-pi, N-rho, N(pi-pi)s, N*-pi, and Delta*-pi.
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2 Questions pertaining to DON-0133 and the non-BRAC Scenario (Portsmouth Naval Shipyard)

2 Questions pertaining to DON-0133 and the non-BRAC Scenario (Portsmouth Naval Shipyard)

Date: August 12, 2005
Creator: United States. Dept. of Defense.
Description: 2 Questions pertaining to DON-0133 and the non-BRAC Senario (Portsmouth Naval Shipyard. Department of Defense Clearinghouse Response: DoD Clearinghouse reply to a letter from the BRAC Commission regarding 2 Questions pertaining to DON-0133 and the non-BRAC scenario (Portsmouth Naval Shipyard)
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A 3.3 MJ, Rb + 1 driver design based on an integrated systems analysis

A 3.3 MJ, Rb + 1 driver design based on an integrated systems analysis

Date: March 7, 2000
Creator: Meier, W R; Barnard, J J & Bangerter, R O
Description: A computer model for systems analysis of heavy ion drivers has been developed and used to evaluate driver designs for inertial fusion energy (IFE). The present work examines a driver for a close-coupled target design that requires less total beam energy but also smaller beam spots sizes than previous target designs. Design parameters and a cost estimate for a 160 beam, 3.3 MJ driver using rubidium ions (A = 85) are reported, and the sensitivity of the results to variations in selected design parameters is given.
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A 3.3 MJ, Rb{sup +1} Driver Design Based on an Integrated Systems Analysis

A 3.3 MJ, Rb{sup +1} Driver Design Based on an Integrated Systems Analysis

Date: September 15, 2000
Creator: Meier, W. R.; Barnard, J. J. & Bangerter, R. O.
Description: A computer model for systems analysis of heavy ion drivers has been developed and used to evaluate driver designs for inertial fusion energy (IFE). The present work examines a driver for a close-coupled target design that requires less total beam energy but also smaller beam spots sizes than previous target designs. Design parameters and a cost estimate for a 160 beam, 3.3 MJ driver using rubidium ions (A = 85) are reported, and the sensitivity of the results to variations in selected design parameters is given.
Contributing Partner: UNT Libraries Government Documents Department
3-D Cavern Enlargement Analyses

3-D Cavern Enlargement Analyses

Date: March 1, 2002
Creator: EHGARTNER, BRIAN L. & SOBOLIK, STEVEN R.
Description: Three-dimensional finite element analyses simulate the mechanical response of enlarging existing caverns at the Strategic Petroleum Reserve (SPR). The caverns are located in Gulf Coast salt domes and are enlarged by leaching during oil drawdowns as fresh water is injected to displace the crude oil from the caverns. The current criteria adopted by the SPR limits cavern usage to 5 drawdowns (leaches). As a base case, 5 leaches were modeled over a 25 year period to roughly double the volume of a 19 cavern field. Thirteen additional leaches where then simulated until caverns approached coalescence. The cavern field approximated the geometries and geologic properties found at the West Hackberry site. This enabled comparisons are data collected over nearly 20 years to analysis predictions. The analyses closely predicted the measured surface subsidence and cavern closure rates as inferred from historic well head pressures. This provided the necessary assurance that the model displacements, strains, and stresses are accurate. However, the cavern field has not yet experienced the large scale drawdowns being simulated. Should they occur in the future, code predictions should be validated with actual field behavior at that time. The simulations were performed using JAS3D, a three dimensional finite element analysis ...
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