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AL 00-3

This abstract painting is mostly black with some white vertical scrapes.
Date: 2000
Creator: Falsetta, Vincent
Object Type: Artwork
System: The UNT Digital Library
0.7-eV GaInAs Junction for a GaInP/GaAs/GaInAs(1-eV)/GaInAs(0.7-eV) Four-Junction Solar Cell: Preprint (open access)

0.7-eV GaInAs Junction for a GaInP/GaAs/GaInAs(1-eV)/GaInAs(0.7-eV) Four-Junction Solar Cell: Preprint

We discuss recent developments in III-V multijunction solar cells, focusing on adding a fourth junction to the Ga0.5In0.5P/GaAs/Ga0.75In0.25As inverted three-junction cell. This cell, grown inverted on GaAs so that the lattice-mismatched Ga0.75In0.25As third junction is the last one grown, has demonstrated 38% efficiency, and 40% is likely in the near future. To achieve still further gains, a lower-bandgap GaxIn1-xAs fourth junction could be added to the three-junction structure for a four-junction cell whose efficiency could exceed 45% under concentration. Here, we present the initial development of the GaxIn1-xAs fourth junction. Junctions of various bandgaps ranging from 0.88 to 0.73 eV were grown, in order to study the effect of the different amounts of lattice mismatch. At a bandgap of 0.88 eV, junctions were obtained with very encouraging {approx}80% quantum efficiency, 57% fill factor, and 0.36 eV open-circuit voltage. The device performance degrades with decreasing bandgap (i.e., increasing lattice mismatch). We model the four-junction device efficiency vs. fourth junction bandgap to show that an 0.7-eV fourth-junction bandgap, while optimal if it could be achieved in practice, is not necessary; an 0.9-eV bandgap would still permit significant gains in multijunction cell efficiency while being easier to achieve than the lower-bandgap junction.
Date: May 1, 2006
Creator: Friedman, D. J.; Geisz, J. F.; Norman, A. G.; Wanlass, M. W. & Kurtz, S. R.
Object Type: Article
System: The UNT Digital Library
The 0.22 Percent Across-the-Board Cut in FY2001 Appropriations (open access)

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

Report describing changes that affected the government budget for the 2001 fiscal year under the Consolidated Appropriations Act.
Date: May 31, 2001
Creator: Keith, Robert
Object Type: Report
System: The UNT Digital Library
The 0.38 Percent Across-the-Board Cut in FY2000 Appropriations (open access)

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

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.
Date: February 25, 2000
Creator: Keith, Robert
Object Type: Report
System: The UNT Digital Library
0.351 micron Laser Beam propagation in High-temperature Plasmas (open access)

0.351 micron Laser Beam propagation in High-temperature Plasmas

A study of the laser-plasma interaction processes have been performed in plasmas that are created to emulate the plasma conditions in indirect drive inertial confinement fusion targets. The plasma emulator is produced in a gas-filled hohlraum; a blue 351-nm laser beam propagates along the axis of the hohlraum interacting with a high-temperature (T{sub e} = 3.5 keV), dense (n{sub e} = 5 x 10{sup 20}cm{sup -3}), long-scale length (L {approx} 2 mm) plasma. Experiments at these conditions have demonstrated that the interaction beam produces less than 1% total backscatter resulting in transmission greater than 90% for laser intensities less than I < 2 x 10{sup 15} W-cm{sup -2}. The bulk plasma conditions have been independently characterized using Thomson scattering where the peak electron temperatures are shown to scale with the hohlraum heater beam energy in the range from 2 keV to 3.5 keV. This feature has allowed us to determine the thresholds for both backscattering and filamentation instabilities; the former measured with absolutely calibrated full aperture backscatter and near backscatter diagnostics and the latter with a transmitted beam diagnostics. A plasma length scaling is also investigated extending our measurements to 4-mm long high-temperature plasmas. At intensities I < 5 x …
Date: December 10, 2007
Creator: Froula, D.; Divol, L.; Meezan, N.; Ross, J.; Berger, R. L.; Michel, P. et al.
Object Type: Report
System: The UNT Digital Library
0.25mm-Thick CCD Packaging for the Dark Energy Survey Camera Array (open access)

0.25mm-Thick CCD Packaging for the Dark Energy Survey Camera Array

Abstract: The Dark Energy Survey Camera focal plane array will consist of 62 2k x 4k CCDs with a pixel size of 15 microns and a silicon thickness of 250 microns for use at wavelengths between 400 and 1000 nm. Bare CCD die will be received from the Lawrence Berkeley National Laboratory (LBNL). At the Fermi National Accelerator Laboratory, the bare die will be packaged into a custom back-side-illuminated module design. Cold probe data from LBNL will be used to select the CCDs to be packaged. The module design utilizes an aluminum nitride readout board and spacer and an Invar foot. A module flatness of 3 microns over small (1 sqcm) areas and less than 10 microns over neighboring areas on a CCD are required for uniform images over the focal plane. A confocal chromatic inspection system is being developed to precisely measure flatness over a grid up to 300 x 300 mm. This system will be utilized to inspect not only room-temperature modules, but also cold individual modules and partial arrays through flat dewar windows.
Date: 2006-06~
Creator: Derylo, Greg; Diehl, H. Thomas & Estrada, Juan
Object Type: Article
System: The UNT Digital Library
0.52eV Quaternary InGaAsSb Thermophotovoltaic Diode Technology (open access)

0.52eV Quaternary InGaAsSb Thermophotovoltaic Diode Technology

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.
Date: June 9, 2004
Creator: Dashiell, M. W.; Beausang, J. F.; Nichols, G.; Depoy, D. M.; Danielson, L. R.; Ehsani, H. et al.
Object Type: Report
System: The UNT Digital Library
1,2-HOIQO--A highly versatile 1,2-HOPO analog (open access)

1,2-HOIQO--A highly versatile 1,2-HOPO analog

A cyclic, bidentate hydroxamic acid binding unit based on an isoquinoline scaffold has been utilized for the synthesis of a hexadentate tripodal ligand based on the TREN backbone. This prototype for a new class of multidentate chelators forms mononuclear iron(III) complexes and one-dimensional coordination polymers with lanthanide(III) cations. The latter has been determined by single crystal X-ray analysis of the cerium species. The solid state structure in the monoclinic space group P2{sub 1}/c (C{sub 36}H{sub 34}CeN{sub 7}O{sub 11}, a = 12.341(2){angstrom}, b = 26.649(4){angstrom}, c = 10.621(2){angstrom}, {alpha} = {gamma} = 90{sup o}, {beta} = 96.753(3){sup o}, V = 3468.6(9) {angstrom}{sup 3}, Z = 4) exhibits a trigonal-dodecahedral environment around the cerium cation. The proof of concept for the versatility of the new scaffold has been shown by the modification of the crucial precursor 3-carboxyiso-coumarin through electrophilic aromatic substitutions to yield the corresponding chlorosulfonated and nitrated analogs.
Date: August 7, 2006
Creator: Seitz, Michael; Pluth, Michael D. & Raymond, Kenneth N.
Object Type: Article
System: The UNT Digital Library
1,2- Hydroxypyridonates as Contrast Agents for Magnetic ResonanceImaging: TREN-1,2-HOPO (open access)

1,2- Hydroxypyridonates as Contrast Agents for Magnetic ResonanceImaging: TREN-1,2-HOPO

1,2-Hydroxypyridinones (1,2-HOPO) form very stable lanthanide complexes that may be useful as contrast agents for Magnetic Resonance Imaging (MRI). X-ray diffraction of single crystals established that the solid state structures of the Eu(III) and the previously reported [Inorg. Chem. 2004, 43, 5452] Gd(III) complex are identical. The recently discovered sensitizing properties of 1,2-HOPO chelates for Eu(III) luminescence allow direct measurement of the number if water molecules in the metal complex. Fluorescence measurements of the Eu(III) complex corroborate that in solution two water molecules coordinate the lanthanide (q = 2) as proposed from the analysis of NMRD profiles. In addition, fluorescence measurements have verified the anion binding interactions of lanthanide TREN-1,2-HOPO complexes in solution, studied by relaxivity, revealing only very weak oxalate binding (K{sub A} = 82.7 {+-} 6.5 M{sup -1}). Solution thermodynamic studies of the metal complex and free ligand have been carried out using potentiometry, spectrophotometry and fluorescence spectroscopy. The metal ion selectivity of TREN-1,2-HOPO supports the feasibility of using 1,2-HOPO ligands for selective lanthanide binding [pGd = 19.3 (2); pZn = 15.2 (2), pCa = 8.8 (3)].
Date: May 8, 2007
Creator: Jocher, Christoph J.; Moore, Evan G.; Xu, Jide; Avedano, Stefano; Botta, Mauro; Aime, Silvio et al.
Object Type: Article
System: The UNT Digital Library
$1.2 Million in Savings Identified in Akzo Nobel Assessment: Plant-Wide Assessment Summary--Chemicals (Fact Sheet) (open access)

$1.2 Million in Savings Identified in Akzo Nobel Assessment: Plant-Wide Assessment Summary--Chemicals (Fact Sheet)

Summary of Akzo Nobel's plant-wide assessment to identify energy and cost saving opportunities at the corporation's Surface Chemistry plant in Morris, Illinois.
Date: August 1, 2003
Creator: unknown
Object Type: Text
System: The UNT Digital Library
$1.2 Million in Savings Identified in Caraustar Assessment: Plant-Wide Assessment Summary--Forest Products (Fact Sheet) (open access)

$1.2 Million in Savings Identified in Caraustar Assessment: Plant-Wide Assessment Summary--Forest Products (Fact Sheet)

Summary of Caraustars plant-wide assessment to identify energy and cost saving opportunities at the corporations recycled paperboard mill in Rittman, Ohio.
Date: August 1, 2003
Creator: unknown
Object Type: Text
System: The UNT Digital Library
1,3-Propanediol Made From Fermentation-Derived Malonic Acid: Office of Industrial Technologies (OIT) Agriculture Project Fact Sheet (open access)

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

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.
Date: September 12, 2001
Creator: Carde, T.
Object Type: Book
System: The UNT Digital Library
1.5-GEV FFAG ACCELERATOR AS INJECTOR TO THE BNL-AGS. (open access)

1.5-GEV FFAG ACCELERATOR AS INJECTOR TO THE BNL-AGS.

A 1.5-GeV Fixed-Field Alternating-Gradient (FFAG) proton Accelerator is being studied as a new injector to the Alternating-Gradient Synchrotron (AGS) of Brookhaven National Laboratory (BNL). The major benefit is that it would considerably shorten the overall AGS acceleration cycle, and, consequently, may yield to an improvement of beam stability, intensity and size. The AGS-FFAG will also facilitate the proposed upgrade of the AGS facility toward a 1-MW average proton beam power at the top energy of 28 GeV. This paper describes the FFAG design for acceleration of protons from 400 MeV to 1.5 GeV, with the same circumference of the AGS, and entirely housed in the AGS tunnel.
Date: July 5, 2004
Creator: Ruggiero, A. G.; Blaskiewicz, M.; Trbojevic, D.; Tsoupas, N. & Zhang, W.
Object Type: Article
System: The UNT Digital Library
1.5-GeV FFAG Accelerator for the AGS Facility (open access)

1.5-GeV FFAG Accelerator for the AGS Facility

N/A
Date: February 1, 2004
Creator: Ruggiero, A. G.; Blaskiewicz, M.; Courant, E.; Trbojevic, D.; Tsoupas, N. & Zhang, W.
Object Type: Report
System: The UNT Digital Library
$1.6 Million in Savings Identified in Anchor Assessment: Plant-Wide Assessment Summary--Glass (Fact Sheet) (open access)

$1.6 Million in Savings Identified in Anchor Assessment: Plant-Wide Assessment Summary--Glass (Fact Sheet)

Summary of Anchor Glass' plant-wide assessment to identify energy and cost saving opportunities at the corporation's facilities in Warner Robins, GA and Jacksonville, FL.
Date: August 1, 2003
Creator: unknown
Object Type: Text
System: The UNT Digital Library
$1.6 Million in Savings Identified in Augusta Newsprint Assessment: Plant-Wide Assessment Summary--Forest Products (Fact Sheet) (open access)

$1.6 Million in Savings Identified in Augusta Newsprint Assessment: Plant-Wide Assessment Summary--Forest Products (Fact Sheet)

Augusta Newsprint and its partners conducted a systematic plant-wide assessment (PWA) to identify energy- and cost-saving opportunities at the company's plant in Augusta, Georgia. The assessment team identified$1.6 million in potential annual savings.
Date: August 1, 2003
Creator: unknown
Object Type: Text
System: The UNT Digital Library

AS 01-7

None
Date: 2001
Creator: Falsetta, Vincent
Object Type: Artwork
System: The UNT Digital Library
A 1.8 Mev K+ injector for the high current beam transport experiment fusion (open access)

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

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.
Date: May 20, 2002
Creator: Kwan, J. W.; Bieniosek, F. M.; Henestroza, E.; Prost, L. & Seidl, P.
Object Type: Article
System: The UNT Digital Library
1-10 Mbar Laser-Driven Shocks Using the Janus Laser Facility (open access)

1-10 Mbar Laser-Driven Shocks Using the Janus Laser Facility

We report preliminary results using the Lawrence Livermore National Laboratory (LLNL) Janus laser facility to generate high pressure laser-driven shocks in the 1-10 Mbar regime. These experiments address various issues, including shock steadiness, planarity, uniformity and low target preheat, important for making precision EOS measurements on a small (E < 250 J) laser facility. A brief description of the experimental techniques, target design and measurements will be given.
Date: August 10, 2001
Creator: Dunn, J.; Price, D. F.; Moon, S. J.; Cauble, R. C.; Springer, P. T. & Ng, A.
Object Type: Article
System: The UNT Digital Library

AZ 01-14

This abstract painting is predominately white with green, pink and gray vertical strokes broken by an implied horizontal line.
Date: 2001
Creator: Falsetta, Vincent
Object Type: Artwork
System: The UNT Digital Library
1/6TH SCALE STRIP EFFLUENT FEED TANK-MIXING RESULTS USING MCU SOLVENT (open access)

1/6TH SCALE STRIP EFFLUENT FEED TANK-MIXING RESULTS USING MCU SOLVENT

The purpose of this task was to determine if mixing was an issue for the entrainment and dispersion of the Modular Caustic Side Solvent Extraction (CSSX) Unit (MCU) solvent in the Defense Waste Processing Facility (DWPF) Strip Effluent Feed Tank (SEFT). The MCU strip effluent stream containing the Cs removed during salt processing will be transferred to the DWPF for immobilization in HLW glass. In lab-scale DWPF chemical process cell testing, mixing of the solvent in the dilute nitric acid solution proved problematic, and the Savannah River National Laboratory (SRNL) was requested to perform scaled SEFT mixing tests to evaluate whether the problem was symptomatic of the lab-scale set-up or of the solvent. The solvent levels tested were 228 and 235 ppm, which represented levels near the estimated DWPF solvent limit of 239 ppm in 0.001M HNO{sub 3} solution. The 239 ppm limit was calculated by Norato in X-CLC-S-00141. The general approach for the mixing investigation was to: (1) Investigate the use of fluorescent dyes to aid in observing the mixing behavior. Evaluate and compare the physical properties of the fluorescent dyed MCU solvents to the baseline Oak Ridge CSSX solvent. Based on the data, use the dyed MCU solvent …
Date: February 1, 2006
Creator: Hansen, E.
Object Type: Report
System: The UNT Digital Library
1-D Equilibrium Discrete Diffusion Monte Carlo (open access)

1-D Equilibrium Discrete Diffusion Monte Carlo

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.
Date: August 2000
Creator: Evans, T. M.; Urbatsch, T. J. & Lichtenstein, H.
Object Type: Article
System: The UNT Digital Library
1-D Van der Waals Foams Heated by Ion Beam Energy Deposition (open access)

1-D Van der Waals Foams Heated by Ion Beam Energy Deposition

One dimensional simulations of various initial average density aluminum foams (modeled as slabs of solid metal separated by low density regions) heated by volumetric energy deposition are conducted with a Lagrangian hydrodynamics code using a van der Waals equation of tate (EOS). The resulting behavior is studied to facilitate the design of future warm dense matter (WDM) experiments at LBNL. In the simulations the energy deposition ranges from 10 to 30 kJ/g and from 0.075 to 4.0 ns total pulse length, resulting in temperatures from approximately 1 o 4 eV. We study peak pressures and temperatures in the foams, expansion velocity, and the phase evolution. Five relevant time scales in the problem are identified. Additionally, we present a method for characterizing the level of inhomogeneity in a foam target as it is heated and the time it takes for a foam to homogenize.
Date: December 23, 2009
Creator: Zylstra, A. B.; Barnard, J. J. & More, R. M.
Object Type: Article
System: The UNT Digital Library
01-ERD-111 - The Development of Synthetic High Affinity Ligands (open access)

01-ERD-111 - The Development of Synthetic High Affinity Ligands

The aim of this project was to develop Synthetic High-Affinity Ligands (SHALs), which bind with high affinity and specificity to proteins of interest for national security and cancer therapy applications. The aim of producing synthetic ligands for sensory devices as an alternative to antibody-based detection assays and therapeutic agents is to overcome the drawbacks associated with antibody-based in next-generation sensors and systems. The focus area of the project was the chemical synthesis of the SHALs. The project concentrated on two different protein targets. (a) The C fragment of tetanus and botulinum toxin, potential biowarfare agents. A SHAL for tetanus or botulinum toxin would be incorporated into a sensory device for the toxins. (b) HLA-DR10, a protein found in high abundance on the surface of Non-Hodgkins Lymphoma. A SHAL specific to a tumor marker, labeled with a radionuclide, would enable the targeted delivery of radiation therapy to metastatic disease. The technical approach used to develop a SHAL for each protein target will be described in more detail below. However, in general, the development of a SHAL requires a combination of computational modeling techniques, modern nuclear magnetic resonance spectroscopy (NMR) and synthetic chemistry.
Date: February 5, 2004
Creator: Perkins, J; Balhorn, R; Cosman, M; Lightstone, F & Zeller, L
Object Type: Report
System: The UNT Digital Library