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3-D DETERMINISTIC TRANSPORT METHODS RESEARCH AT LANL UNDER ASCI (open access)

3-D DETERMINISTIC TRANSPORT METHODS RESEARCH AT LANL UNDER ASCI

None
Date: January 1, 2000
Creator: Morel, J.
Object Type: Article
System: The UNT Digital Library
2020 Foresight Forging the Future of Lawrence Livermore National Laboratory (open access)

2020 Foresight Forging the Future of Lawrence Livermore National Laboratory

The Lawrence Livermore National Laboratory (LLNL) of 2020 will look much different from the LLNL of today and vastly different from how it looked twenty years ago. We, the members of the Long-Range Strategy Project, envision a Laboratory not defined by one program--nuclear weapons research--but by several core programs related to or synergistic with LLNL's national security mission. We expect the Laboratory to be fully engaged with sponsors and the local community and closely partnering with other research and development (R&D) organizations and academia. Unclassified work will be a vital part of the Laboratory of 2020 and will visibly demonstrate LLNL's international science and technology strengths. We firmly believe that there will be a critical and continuing role for the Laboratory. As a dynamic and versatile multipurpose laboratory with a national security focus, LLNL will be applying its capabilities in science and technology to meet the needs of the nation in the 21st century. With strategic investments in science, outstanding technical capabilities, and effective relationships, the Laboratory will, we believe, continue to play a key role in securing the nation's future.
Date: January 1, 2000
Creator: Chrzanowski, P.
Object Type: Report
System: The UNT Digital Library
ACTINYL(VI) SPECIATION IN CONCENTRATED SODIUM CHLORIDE SOLUTIONS (open access)

ACTINYL(VI) SPECIATION IN CONCENTRATED SODIUM CHLORIDE SOLUTIONS

None
Date: January 1, 2000
Creator: Runde, W. & Neu, M.
Object Type: Article
System: The UNT Digital Library
ADVANCED DIRECT LIQUEFACTION CONCEPTS FOR PETC GENERIC UNITS (open access)

ADVANCED DIRECT LIQUEFACTION CONCEPTS FOR PETC GENERIC UNITS

The results of Laboratory and Bench-Scale experiments and supporting technical and economic assessments conducted under DOE Contract No. DE-AC22-91PC91040 is reported for the period October 1, 1999 to December 31, 1999. This contract is with the University of kentucky Research Foundation, which supports work with the University of Kentucky Center for Applied Energy Researc, CONSOL, Inc., LDP Associates, and Hydrocarbon Technologies, Inc. This work involves the introduction into the basic two-stage liquefaction process several novel concepts, which include dispersed lower-cost catalysts, coal cleaning by oil agglomeration, and distillate hydrotreating and dewaxing. This project has been modified to include an investigation into the production of value added materials from coal using liquefaction based technologies.
Date: January 1, 2000
Creator: Berkovich, Adam J.
Object Type: Report
System: The UNT Digital Library
Advanced Fusion Power Plant Studies. Annual Report for 1999 (open access)

Advanced Fusion Power Plant Studies. Annual Report for 1999

Significant progress in physics understanding of the reversed shear advanced tokamak regime has been made since the last ARIES-RS study was completed in 1996. The 1999 study aimed at updating the physics design of ARIES-RS, which has been renamed ARIES-AT, using the improved understanding achieved in the last few years. The new study focused on: Improvement of beta-limit stability calculations to include important non-ideal effects such as resistive wall modes and neo-classical tearing modes; Use of physics based transport model for internal transport barrier (ITB) formation and sustainment; Comparison of current drive and rotational flow drive using fast wave, electron cyclotron wave and neutral particle beam; Improvement in heat and particle control; Integrated modeling of the optimized scenario with self-consistent current and transport profiles to study the robustness of the bootstrap alignment, ITB sustainment, and stable path to high beta and high bootstrap fraction operation.
Date: January 1, 2000
Creator: Chan, V. S.; Chu, M. S.; Greenfield, C. M.; Kinsey, J. E. & al., et
Object Type: Report
System: The UNT Digital Library
ADVANCED GAS TURBINE SYSTEMS RESEARCH (open access)

ADVANCED GAS TURBINE SYSTEMS RESEARCH

The activities of the Advanced Gas Turbine Systems Research (AGRSR) program are described in the quarterly report. The report is divided into discussions of Membership, Administration, Technology Transfer (Workshop/Education) and Research. Items worthy of note are presented in extended bullet format following the appropriate heading.
Date: January 1, 2000
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Advanced high temperature superconductor film-based process using RABiTS (open access)

Advanced high temperature superconductor film-based process using RABiTS

The purpose of this Cooperative Research and Development Agreement (CRADA) between Lockheed Martin Energy Research Corporation (Contractor), Managing contractor for Oak Ridge National Laboratory (ORNL) and Midwest Superconductivity, Inc. (MSI) and Westinghouse Science and Electric Company (WEC) was to develop the basis for a commercial process for the manufacturing of superconducting tape based on the RABiTS technology developed at ORNL. The chosen method for deposition of YBCO films on RABiTS was Metal Organic chemical Vapor Deposition (MOCVD).
Date: January 1, 2000
Creator: Goyal, A.; Hawsey, R.A.; Hack, J. & Moon, D.
Object Type: Report
System: The UNT Digital Library
Advanced laser diodes for sensing applications (open access)

Advanced laser diodes for sensing applications

The authors have developed diode lasers for short pulse duration and high peak pulse power in the 0.01--100.0 m pulsewidth regime. A primary goal of the program was producing up to 10 W while maintaining good far-field beam quality and ease of manufacturability for low cost. High peak power, 17 W, picosecond pulses have been achieved by gain switching of flared geometry waveguide lasers and amplifiers. Such high powers area world record for this type of diode laser. The light emission pattern from diode lasers is of critical importance for sensing systems such as range finding and chemical detection. They have developed a new integrated optical beam transformer producing rib-waveguide diode lasers with a symmetric, low divergence, output beam and increased upper power limits for irreversible facet damage.
Date: January 1, 2000
Creator: Vawter, Gregory A.; Mar, Alan; Chow, Weng W. & Allerman, Andrew A.
Object Type: Report
System: The UNT Digital Library
ADVANCED SORBENT DEVELOPMENT (open access)

ADVANCED SORBENT DEVELOPMENT

The overall objective of this program was to develop regenerable sorbents for use in the temperature range of 343 to 538 C (650 to 1000 F) to remove hydrogen sulfide (H{sub 2}S) from coal-derived fuel gases in a fluidized-bed reactor. The goal was to develop sorbents that are capable of reducing the H{sub 2}S level in the fuel gas to less than 20 ppmv in the specified temperature range and pressures in the range of 1 to 20 atmospheres, with chemical characteristics that permit cyclic regeneration over many cycles without a drastic loss of activity, as well as physical, characteristics that are compatible with the fluidized bed application. This topical report focuses on the investigation directed toward preparation of zinc-based sorbents using the sol-gel approach that has been shown to require only a moderate temperature for calcination, while resulting in significantly more attrition-resistant sorbents. The sorbents prepared in this part of the investigation and the results from their evaluation in packed-bed and fluidized-bed reactors are described in this report.
Date: January 1, 2000
Creator: Abbasian, Javad
Object Type: Report
System: The UNT Digital Library
AGE-RELATED CHANGES IN PU DEDUCED FROME XAFS DATA WITH A NEW SUPER-RESOLUTION FAST FOURIER TRANSFORM (open access)

AGE-RELATED CHANGES IN PU DEDUCED FROME XAFS DATA WITH A NEW SUPER-RESOLUTION FAST FOURIER TRANSFORM

None
Date: January 1, 2000
Creator: ZWEIG, G. & WOHLBERG, B.
Object Type: Article
System: The UNT Digital Library
Los Alamos Plutonium Facility Waste Management System (open access)

Los Alamos Plutonium Facility Waste Management System

None
Date: January 1, 2000
Creator: Smith, C. A. & Sparks, D.
Object Type: Article
System: The UNT Digital Library
All-Hot-Wire Chemical Vapor Deposition a-Si:H Solar Cells (open access)

All-Hot-Wire Chemical Vapor Deposition a-Si:H Solar Cells

Efficient hydrogenated amorphous silicon (a-Si:H) nip solar cells have been fabricated with all doped and undoped a-Si:H layers deposited by hot-wire chemical vapor deposition (HWCVD). The total deposition time of all layers, except the top ITO-contact, is less than 4 minutes.
Date: January 1, 2000
Creator: Iwaniczko, E.; Wang, Q.; Xu, Y.; Nelson, B. P.; Mahan, A. H.; Crandall, R. S. et al.
Object Type: Article
System: The UNT Digital Library
ALTERNATING CURRENT LOSSES IN AG-SHEATHED BSCCO (2212 AND 2223) TAPES AND WIRES AND YBCO (123) COATED CONDUCTORS (open access)

ALTERNATING CURRENT LOSSES IN AG-SHEATHED BSCCO (2212 AND 2223) TAPES AND WIRES AND YBCO (123) COATED CONDUCTORS

In this study, we focus on the examination of ac losses in conductors utilizing Bi{sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O [BSCCO (2223)] high TC superconductors (HTS). In addition, we seek to assist other facilities such as the University of Wisconsin-Madison Applied Superconductivity Center (UW-ASC), Brookhaven National Laboratory, and other DoE facilities investigating the use of HTS in electric power applications (e.g., generators, motors, and transformers). To accomplish this we will develop an ac losses capability at Clark Atlanta University to complement the established ac losses efforts at Brookhaven National Laboratory (BSCCO) on BSCCO/Ag and various material characterization efforts taking place at the UW-ASC. Our goal is through this effort to gain a greater understanding of the effects on ac losses due to parameters such as ac/dc current, J{sub c}, tape geometry, voltage tap placement, field orientation, material anisotropy, surface irregularities, percolations and filament coupling effects. As a result, we expect to better understand how to minimize ac losses in applications requiring real or practical conductors. HTS conductors based on BSCCO-2223 are now being routinely produced in industrial lengths of high quality. Vendors such as Southwire and ASC are producing multi-filamentary tapes in lengths of 6 km or more carrying critical current …
Date: January 1, 2000
Creator: Hurley, John S.
Object Type: Report
System: The UNT Digital Library
Analysis of Moisture and CO(2) Uptake in Anhydrous CdCl(2) Powders Used for Vapor CdCl(2) Treatment of CdS/CdTe PV Devices (open access)

Analysis of Moisture and CO(2) Uptake in Anhydrous CdCl(2) Powders Used for Vapor CdCl(2) Treatment of CdS/CdTe PV Devices

Water and CO(2) uptake in CdCl(2) powder precursors was investigated using thermogravimetric analysis/Fourier transform infrared spectroscopy (TGA/FTIR). Exposure of powders under ambient conditions shows that a steady-state hydration level near 9% (by weight) is achieved after brief exposure to room air.
Date: January 1, 2000
Creator: Mazur, T.; Gessert, T.; Martins, G. & Curtis, C.
Object Type: Article
System: The UNT Digital Library
Analysis of the radiation fallout tests at ETBS, France (Fall 1996) (open access)

Analysis of the radiation fallout tests at ETBS, France (Fall 1996)

A series of experiments were carried out at the Etablissement Technique de Bourges (ETBS), France to measure protection factors for the Russian T72M tank during exposure to gamma radiation emanating from the ground. The purpose of these measurements was to determine the reduction in the dose rate to the tank occupants when the vehicle traverses terrain that has been contaminated as the result of fallout from a nuclear weapon or when the ground has been contaminated by the distribution of radioactive material by terrorists. This report summarizes results of calculations that replicate the measurements. Comparisons of measured and calculated protection factors are reported for a series of nested iron cylinders and the T72M tank. The cylinder measurements were performed to compare protection factors measured at Bourges with those obtained previously at the US Army Aberdeen Test Center.
Date: January 1, 2000
Creator: Barnes, J. M. & Santoro, R. T.
Object Type: Report
System: The UNT Digital Library
Anomalous {gamma} {r_arrow} 3{pi} amplitude in a bound-state approach (open access)

Anomalous {gamma} {r_arrow} 3{pi} amplitude in a bound-state approach

The form factor for the anomalous process {gamma}{pi}{sup +} {r_arrow} pi{sub +}{pi}{sup 0}, which is presently being measured at CEBAF, is calculated in the Schwinger-Dyson approach in conjunction with an impulse approximation. The form factors obtained by the author are compared with the ones predicted by the simple constituent quark loop model, vector meson dominance and chiral perturbation theory, as well as the scarce already available data.
Date: January 1, 2000
Creator: Bistrovic, Bojan & Klabucar, Dubravko
Object Type: Article
System: The UNT Digital Library
APPLICATION OF FUZZY SET THEORY FOR EXPOSURE CONTROL IN BERYLLIUM PART MANUFACTURING (open access)

APPLICATION OF FUZZY SET THEORY FOR EXPOSURE CONTROL IN BERYLLIUM PART MANUFACTURING

None
Date: January 1, 2000
Creator: Parkinson, W.J. & Abeln, S.P.
Object Type: Article
System: The UNT Digital Library
AN ASSESSMENT OF MCNP WEIGHT WINDOWS (open access)

AN ASSESSMENT OF MCNP WEIGHT WINDOWS

The weight window variance reduction method in the general-purpose Monte Carlo N-Particle radiation transport code MCNPTM has recently been rewritten. In particular, it is now possible to generate weight window importance functions on a superimposed mesh, eliminating the need to subdivide geometries for variance reduction purposes. Our assessment addresses the following questions: (1) Does the new MCNP4C treatment utilize weight windows as well as the former MCNP4B treatment? (2) Does the new MCNP4C weight window generator generate importance functions as well as MCNP4B? (3) How do superimposed mesh weight windows compare to cell-based weight windows? (4) What are the shortcomings of the new MCNP4C weight window generator? Our assessment was carried out with five neutron and photon shielding problems chosen for their demanding variance reduction requirements. The problems were an oil well logging problem, the Oak Ridge fusion shielding benchmark problem, a photon skyshine problem, an air-over-ground problem, and a sample problem for variance reduction.
Date: January 1, 2000
Creator: HENDRICKS, J. S. & CULBERTSON, C. N.
Object Type: Article
System: The UNT Digital Library
Asynchronous parallel pattern search for nonlinear optimization (open access)

Asynchronous parallel pattern search for nonlinear optimization

Parallel pattern search (PPS) can be quite useful for engineering optimization problems characterized by a small number of variables (say 10--50) and by expensive objective function evaluations such as complex simulations that take from minutes to hours to run. However, PPS, which was originally designed for execution on homogeneous and tightly-coupled parallel machine, is not well suited to the more heterogeneous, loosely-coupled, and even fault-prone parallel systems available today. Specifically, PPS is hindered by synchronization penalties and cannot recover in the event of a failure. The authors introduce a new asynchronous and fault tolerant parallel pattern search (AAPS) method and demonstrate its effectiveness on both simple test problems as well as some engineering optimization problems
Date: January 1, 2000
Creator: Hough, P. D.; Kolda, T. G. & Torczon, V. J.
Object Type: Report
System: The UNT Digital Library
AUTOMATED DECONTAMINATION OF NUCLEAR MATERIAL CONTAINERS AT LOS ALAMOS NATIONAL LABORATORY (open access)

AUTOMATED DECONTAMINATION OF NUCLEAR MATERIAL CONTAINERS AT LOS ALAMOS NATIONAL LABORATORY

None
Date: January 1, 2000
Creator: Dennison, D.K. & Gallant, D.A.
Object Type: Article
System: The UNT Digital Library
AVATAR -- Adaptive Visualization Aid for Touring And Recovery (open access)

AVATAR -- Adaptive Visualization Aid for Touring And Recovery

This document provides a report on the initial development of software which uses a standard visualization tool to determine, label and display salient regions in large 3D physics simulation datasets. This software uses parallel pattern recognition behind the scenes to handle the huge volume of data. This software is called AVATAR (Adaptive Visualization Aid for Touring and Recovery). It integrates approaches to gathering labeled training data, learning from large training sets utilizing parallelism and the final display of salient data in unseen visualization data sets. The paper uses vorticity fields for a large-eddy simulation to illustrate the method.
Date: January 1, 2000
Creator: Hall, L. O.; Bowyer, K. W.; Chawla, N.; T. Moore, Jr. & Kegelmeyer, W. P.
Object Type: Report
System: The UNT Digital Library
Ballistic Missile Silo Door Monitoring Analysis (open access)

Ballistic Missile Silo Door Monitoring Analysis

This paper compares the cost and effectiveness of several potential options that may be used to monitor silo-based ballistic missiles. Silo door monitoring can be used to verify that warheads removed to deactivate or download silo-based ballistic missiles have not been replaced. A precedent for monitoring warhead replacement using reentry vehicle on site inspections (RV-OSIs) and using satellites has been established by START-I and START-II. However, other monitoring options have the potential to be less expensive and more effective. Three options are the most promising if high verification confidence is desired: random monitoring using door sensors; random monitoring using manned or unmanned aircraft; and continuous remote monitoring using unattended door sensors.
Date: January 1, 2000
Creator: Edenburn, Michael W. & Trost, Lawrence C.
Object Type: Report
System: The UNT Digital Library
BAs-GaAs Semiconductor Alloys as a Photovoltaic Alternative to Nitride Alloys (open access)

BAs-GaAs Semiconductor Alloys as a Photovoltaic Alternative to Nitride Alloys

Nitrogen alloyed III-V semiconductor compounds have been intensely studied in recent years due to unusual effects caused by nitrogen alloying. These effects are exploited in band gap engineering for specific applications such as solar cells and blue lasers.
Date: January 1, 2000
Creator: Hart, G. L. W. & Zunger, A.
Object Type: Article
System: The UNT Digital Library
BENCH-SCALE DEMONSTRATION OF HOT-GAS DESULFURIZATION TECHNOLOGY (open access)

BENCH-SCALE DEMONSTRATION OF HOT-GAS DESULFURIZATION TECHNOLOGY

None
Date: January 1, 2000
Creator: Gangwal, Santosh K. & Portzer, Jeffrey W.
Object Type: Report
System: The UNT Digital Library