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Generalized System of Preferences

Description: This report provides information about the Generalized System of Preferences which provides duty-free treatment for products that are imported from some designated countries. The main purpose is to promote economic growth.
Date: August 12, 2002
Creator: Cooper, William H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Wafer-Bonded Internal Back-Surface Reflectors for Enhanced TPV Performance

Description: This paper discusses recent efforts to realize GaInAsSb/GaSb TPV cells with an internal back-surface reflector (BSR). The cells are fabricated by wafer bonding the GaInAsSb/GaSb device layers to GaAs substrates with a dielectric/Au reflector, and subsequently removing the GaSb substrate. The internal BSR enhances optical absorption within the device while the dielectric layer provides electrical isolation. This approach is compatible with monolithic integration of series-connected TPV cells and… more
Date: August 12, 2002
Creator: Wang, C. A.; Murphy, P. G.; O'Brien, P. W.; Shiau, D. A.; Anderson, A. C.; Liau, Z. L. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Investigations of Probe Induced Perturbations in a Hall Thruster

Description: An electrostatic probe used to measure spatial plasma parameters in a Hall thruster generates perturbations of the plasma. These perturbations are examined by varying the probe material, penetration distance, residence time, and the nominal thruster conditions. The study leads us to recommendations for probe design and thruster operating conditions to reduce discharge perturbations, including metal shielding of the probe insulator and operation of the thruster at lower densities.
Date: August 12, 2002
Creator: Staack, D.; Raitses, Y. & Fisch, N. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Noncontiguous I/O through PVFS.

Description: With the tremendous advances in processor and memory technology, I/O has risen to become the bottleneck in high-performance computing for many applications. The development of parallel file systems has helped to ease the performance gap, but I/O still remains an area needing significant performance improvement. Research has found that noncontiguous I/O access patterns in scientific applications combined with current file system methods to perform these accesses lead to unacceptable performance … more
Date: August 12, 2002
Creator: Ching, A.; Choudhary, A.; Liao, W.-K.; Ross, R. & Gropp, W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Electrolytic reduction of spent oxide fuel -- bench-scale test preparations.

Description: Preparations are underway to demonstrate the electrolytic reduction of spent oxide nuclear fuel in the Hot Fuel Examination Facility (HFEF) and Argonne National Laboratory--West (ANL-W). The electrolytic reduction process, developed by the Laboratory's Chemical Technology Division, operates in an electrochemical cell that uses a molten solution of lithium chloride and dissolved lithium oxide as the electrolyte. The spent oxide fuel is loaded into a permeable steel basket as the cathode in the e… more
Date: August 12, 2002
Creator: Herrmann, S. D.; Li, S. X.; Simpson, M. F. & Wahlquist, D. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Spin-echo resolved grazing incidence scattering (ESRGIS) of cold neutrons.

Description: The conceptual design of a new instrument is presented, which makes use of the spin echo technique to analyze the scattering angle of neutrons impinging upon a rough or corrugated surface at grazing incidence. In a grazing incidence geometry the roughness of the surface and of submersed interfaces give rise to a neutron scattering pattern at angles well resolved from that of specular reflection for corrugation lengths up to several microns, but only in the plane of specular reflection. In contr… more
Date: August 12, 2002
Creator: Felcher, G. P.; te Velthuis, S. G. E.; Major, J.; Dosch, H.; Anderson, C.; Habicht, K. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Gene-Enzyme Relationships of Aromatic Amino Acid Biosynthesis in Higher Plants

Description: Inhibition studies of amino acids in Nicotiana silvestris suspension cells gave clues to the difficulties for obtaining mutants deficient in post prephenate pathway proteins of aromatic amino acid biosynthesis (prephenate aminotransferase, arogenate dehydrogenase and arogenate dehydratase). Such mutants, if successfully obtained, would allow gene-enzyme relationships of aromatic amino acid proteins to be studied. We found that amino acids were inhibitory toward plant cell growth, and thus were … more
Date: August 12, 2002
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Accelerator-based validation of shielding codes

Description: The space radiation environment poses risks to astronaut health from a diverse set of sources, ranging from low-energy protons and electrons to highly-charged, high-energy atomic nuclei and their associated fragmentation products, including neutrons. The low-energy protons and electrons are the source of most of the radiation dose to Shuttle and ISS crews, while the more energetic particles that comprise the Galactic Cosmic Radiation (protons, He, and heavier nuclei up to Fe) will be the domina… more
Date: August 12, 2002
Creator: Zeitlin, Cary; Heilbronn, Lawrence; Miller, Jack & Wilson, John W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Higher temperature reactor materials workshop sponsored by the Department of Energy Office of Nuclear Energy, Science, and Technology (NE) and the Office of Basic Energy Sciences (BES).

Description: On March 18-21, 2002, the Department of Energy, Office of Nuclear Energy, Science, and Technology (NE) and the Office of Basic Energy Sciences (BES) sponsored a workshop to identify needs and opportunities for materials research aimed at performance improvements of structural materials in higher temperature reactors. The workshop focused discussion around the reactor concepts proposed as part of the Generation IV Nuclear Energy System Roadmap. The goal of the Generation IV initiative is to make… more
Date: August 12, 2002
Creator: Allen, T.; Bruemmer, S.; Kassner, M.; Odette, R.; Stoller, R.; Was, G. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A linear actuator system with 1-angstrom closed-loop control resolution and 50-millimeter travel range.

Description: We have designed and tested a novel linear actuator system with 1-angstrom closed-loop control resolution and 50-mm travel range. There are two major ultraprecision motion control techniques that have been applied to this actuator: A novel laser Doppler encoder system with multiple-reflection optics; and A specially designed high-stiffness weak-link mechanism with stacked thin metal sheets having sub-angstrom driving sensitivity with excellent stability. In this paper, we present the system des… more
Date: August 12, 2002
Creator: Shu, D.; Han, Y.; Toellner, T. S. & Alp, E. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Laser rock drilling by a super-pulsed CO{sub 2} laser beam.

Description: High power carbon dioxide lasers have successfully been used in drilling or cutting engineering materials such as metals, polymers and ceramics over the years. Can a carbon dioxide laser be used to efficiently drill different rocks in a deep gas well? Research sponsored by US Department of Energy has been carried out to answer this question. This paper will report the study results of using a super-pulsed CO{sub 2} laser beam to drill rocks. A 6 kW CO{sub 2} laser operated at superpulse mode wa… more
Date: August 12, 2002
Creator: Xu, Z.; Reed, C. B.; Parker, R. A.; Gahan, B. C.; Graves, R. M. & Figueroa, H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Enabling cleanup technology transfer.

Description: Technology transfer in the environmental restoration, or cleanup, area has been challenging. While there is little doubt that innovative technologies are needed to reduce the times, risks, and costs associated with the cleanup of federal sites, particularly those of the Departments of Energy (DOE) and Defense, the use of such technologies in actual cleanups has been relatively limited. There are, of course, many reasons why technologies do not reach the implementation phase or do not get transf… more
Date: August 12, 2002
Creator: Ditmars, J. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Achieving High Dopant Concentrations in Si: First Principles Simulations

Description: In this paper we discuss methods to obtain high dopant concentrations during processing of Si devices. The possibility of increasing the solubility of B in Si by misfit stress is investigated. The enthalpy of B atoms is calculated, with and without stress, using density functional theory. A second approach, the trapping of excess dopant atoms during deposition of Si, is also considered. For this purpose, the enthalpies of several dopant species in sites near the surface are calculated.
Date: August 12, 2002
Creator: Centoni, S A; Sadigh, B; Caturla, M J; Gilmer, G H & Diaz de la Rubia, T
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

A Computer Generated Reduced Iso-Octane Chemical Kinetic Mechanism Applied to Simulation of HCCI Combustion

Description: This paper shows how a computer can systematically remove non-essential chemical reactions from a large chemical kinetic mechanism. The computer removes the reactions based upon a single solution using a detailed mechanism. The resulting reduced chemical mechanism produces similar numerical predictions significantly faster than predictions that use the detailed mechanism. Specifically, a reduced chemical kinetics mechanism for iso-octane has been derived from a detailed mechanism by eliminating… more
Date: August 12, 2002
Creator: Aceves, S. M.; Martinez-Frias, J.; Flowers, D.; Smith, J. R.; Dibble, R. & Chen, J. Y.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Batch Preheat for glass and related furnace processing operations

Description: The objectives that our development work addressed are: (1) Establish through lab tests a salt eutectic with a melting point of about 250 F and a working range of 250 to 1800 F. (2) Establish the most economical material of construction for the screened salt eutectics identified in the first objective. (3) Establish the material of construction for the salt heater liner. Objectives 2 and 3 were determined through corrosion tests using selected metallurgical samples. Successful completion of the… more
Date: August 12, 2002
Creator: Energy & Environmental Resources, Inc
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Biaxially aligned template films fabricated by inclined-substrate deposition for YBCO-coated conductor applications.

Description: Inclined substrate deposition (ISD) has the potential for rapid production of high-quality biaxially textured buffer layers, which are important for YBCO-coated conductor applications. We have grown biaxially textured MgO films by ISD at deposition rates of 20-100 {angstrom}/sec. Columnar grains with a roof-tile surface structure were observed in the ISD-MgO films. X-ray pole figure analysis revealed that the (002) planes of the ISD-MgO films are tilted at an angle from the substrate normal. A … more
Date: August 12, 2002
Creator: Ma, B.; Li, M.; Koritala, R. E.; Fisher, B. L.; Erck, R. A.; Dorris, S. E. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Generalized System of Preferences

Description: This report provides information about the Generalized System of Preferences which provides duty free treatment for products that are imported from some designated countries. The main purpose is to promote economic growth.
Date: August 12, 2002
Creator: Cooper, William H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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