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1-MeV-Electron Irradiation of GaInAsN Cells: Preprint

Description: This conference paper describes the GaInAsN cells that are measured to retain 933% and 894% of their original efficiency after exposure to 5 X 1014 and 1 X 1015 cm-2 1-MeV electrons, respectively. The rate of degradation is not correlated with the performance at beginning of life (BOL). The depletion width remains essentially unchanged, increasing by< 1%. Temperature-coefficient data for GaInAsN cells are also presented. These numbers are used to project the efficiency of GaInAsN-containing multijunction cells. The GaInAsN junction is not currently predicted to increase the efficiencies of the multijunction cells. Nevertheless, GaInAsN-containing multijunction cell efficiencies are predicted to be comparable to those of the conventional structures, and even small improvements in the GaInAsN cell may lead to higher multijunction cell efficiencies, especially for high-radiation applications and when cell operating temperature is low.
Date: May 1, 2002
Creator: Kurtz, Sarah; King, R. R.; Edmondson, K. M.; Friedman, D. J. & Karam, N. H.
Partner: UNT Libraries Government Documents Department
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3-D Cavern Enlargement Analyses

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 code for nonlinear quasi-static solids. The results examine the impacts of leaching and cavern workovers, where internal cavern pressures are reduced, on surface subsidence, well integrity, and cavern stability. The results suggest that the current limit of 5 oil drawdowns may be extended with some mitigative action required on the wells and later on to surface structure due to subsidence strains. The predicted stress state in the salt shows damage to start occurring after 15 drawdowns with significant failure occurring at the 16th drawdown, well beyond the current limit of 5 drawdowns.
Date: March 1, 2002
Creator: EHGARTNER, BRIAN L. & SOBOLIK, STEVEN R.
Partner: UNT Libraries Government Documents Department
open access

A 3-D ray-trace model for an AMR code on distributed processors

Description: Distributed memory AMR codes provide a special challenge for laser ray-trace modeling. For RAGE we follow the energy-carrying rays through each cell, checking for crossings which require collection a new cell index (1 of 9 in 2D). Density gradients for ray deflections can be calculated 'on the fly.' Substantial excursions must be made from the legacy PIC particle area-weighting approach, but this serves as a useful 1st step. Similarly, IDL now offers a quick graphical rendering, while ENSIGHT graphics beautifully captures the 3D light refraction and deposition.
Date: January 1, 2002
Creator: Mason, R. J. (Rodney J.)
Partner: UNT Libraries Government Documents Department
open access

A 3-D Vortex Code for Parachute Flow Predictions: VIPAR Version 1.0

Description: This report describes a 3-D fluid mechanics code for predicting flow past bluff bodies whose surfaces can be assumed to be made up of shell elements that are simply connected. Version 1.0 of the VIPAR code (Vortex Inflation PARachute code) is described herein. This version contains several first order algorithms that we are in the process of replacing with higher order ones. These enhancements will appear in the next version of VIPAR. The present code contains a motion generator that can be used to produce a large class of rigid body motions. The present code has also been fully coupled to a structural dynamics code in which the geometry undergoes large time dependent deformations. Initial surface geometry is generated from triangular shell elements using a code such as Patran and is written into an ExodusII database file for subsequent input into VIPAR. Surface and wake variable information is output into two ExodusII files that can be post processed and viewed using software such as EnSight{trademark}.
Date: July 1, 2002
Creator: Strickland, James H.; Homicz, Gregory F.; Porter, Vicki L. & Gossler, Albert A.
Partner: UNT Libraries Government Documents Department
open access

24-CHANNEL GEOPHONE ARRAY FOR HORIZONTAL OR VERTICAL BOREHOLES

Description: This report describes the technical progress on a project to design and construct a multi-channel geophone array that improves tomographic imaging capabilities in both surface and underground mines. Especially important in the design of the array is sensor placement. One issue related to sensor placement is addressed in this report: the method for clamping the sensor once it is emplaced in the borehole. If the sensors (geophones) are not adequately coupled to the surrounding rock mass, the resulting data will be of very poor quality. Improved imaging capabilities will produce energy, environmental, and economic benefits by increasing exploration accuracy and reducing operating costs.
Date: August 1, 2002
Creator: Westman, Erik C.
Partner: UNT Libraries Government Documents Department
open access

24-CHANNEL GEOPHONE ARRAY FOR HORIZONTAL OR VERTICAL BOREHOLES

Description: This report describes the technical progress on a project to design and construct a multi-channel geophone array that improves tomographic imaging capabilities in both surface and underground mines. Especially important in the design of the array is sensor placement. One issue related to sensor placement is addressed in this report: the method for orienting the sensor once it is emplaced in the borehole. If the sensors (geophones) do not have the same orientation, the data will be essentially worthless. Improved imaging capabilities will produce energy, environmental, and economic benefits by increasing exploration accuracy and reducing operating costs.
Date: July 1, 2002
Creator: Westman, Erik C.
Partner: UNT Libraries Government Documents Department
open access

24 CHANNEL GEOPHONE ARRAY FOR HORIZONTAL OR VERTICAL BOREHOLES

Description: This report describes the technical progress on a project to design and construct a multi-channel geophone array that improves tomographic imaging capabilities in both surface and underground mines. Especially important in the design of the array is sensor placement. One issue related to sensor placement is addressed in this report: the method of emplacing the array in a long, horizontal borehole. Improved imaging capabilities will produce energy, environmental, and economic benefits by increasing exploration accuracy and reducing operating costs.
Date: July 1, 2002
Creator: Westman, Erik C.
Partner: UNT Libraries Government Documents Department
open access

24-CHANNEL GEOPHONE ARRAY FOR HORIZONTAL OR VERTICAL BOREHOLES

Description: This report describes the technical progress on a project to design and construct a multi-channel geophone array that improves tomographic imaging capabilities in both surface and underground mines. Especially important in the design of the array is sensor placement. One issue related to sensor placement is addressed in this report: the development of simple, robust, MSHA-acceptable clamping unit. Improved imaging capabilities will produce energy, environmental, and economic benefits by increasing exploration accuracy and reducing operating costs.
Date: July 1, 2002
Creator: Westman, Erik C.
Partner: UNT Libraries Government Documents Department
open access

24-CHANNEL GEOPHONE ARRAY FOR HORIZONTAL OR VERTICAL BOREHOLES

Description: This report describes the technical progress on a project to design and construct a multi-channel geophone array that improves tomographic imaging capabilities in both surface and underground mines. Especially important in the design of the array is sensor placement. One issue related to sensor placement is addressed in this report: the method for clamping the sensor once it is emplaced in the borehole. If the sensors (geophones) are not adequately coupled to the surrounding rock mass, the resulting data will be of very poor quality. Improved imaging capabilities will produce energy, environmental, and economic benefits by increasing exploration accuracy and reducing operating costs.
Date: July 1, 2002
Creator: Westman, Erik C.
Partner: UNT Libraries Government Documents Department
open access

24-CHANNEL GEOPHONE ARRAY FOR HORIZONTAL OR VERTICAL BOREHOLES

Description: This report describes the technical progress on a project to design and construct a multi-channel geophone array that improves tomographic imaging capabilities in both surface and underground mines. Especially important in the design of the array is sensor placement. One issue related to sensor placement is addressed in this report: the method for clamping the sensor once it is emplaced in the borehole. If the sensors (geophones) are not adequately coupled to the surrounding rock mass, the resulting data will be of very poor quality. Improved imaging capabilities will produce energy, environmental, and economic benefits by increasing exploration accuracy and reducing operating costs.
Date: August 1, 2002
Creator: Westman, Erik C.
Partner: UNT Libraries Government Documents Department
open access

25 years of technical advances in RFQ accelerators

Description: The radio frequency quadrupole (RFQ) accelerator began as 'The ion linear accelerator with space-uniform strong focusing' conceived by I. M. Kapchinskii and V. A. Teplyakove. In 1979, R. H. Stokes, K. R. Crandall, J. E. Stovall and D. A. Swenson gave this concept the name RFQ. And by 1983, at least 15 laboratories throughout the world were working on various FWQ designs. In the early years, there were many types of geometry considered for the RFQ, but only a few types have survived. The two cavity geometries now used in almost all RFQs are the 4-vane and 4-rod structures. The 4-vane structure is the most popular because its operating frequency range (80 to -500 MHz) is suitable for light ions. Heavy ions require low frequencies (below 200 MHz). Because the 4-rod structure has smaller transverse dimensions than a 4-vane RFQ at the same frequency, the 4-rod RFQ is often preferred for these applications. This paper will describe how the RFQ accelerates and focuses the beam. The paper also discusses some of the important technical advances in designing and building RFQs.
Date: January 1, 2002
Creator: Young, L. M. (Lloyd M.)
Partner: UNT Libraries Government Documents Department
open access

148-Gd cross section measurements for accelerator target facilities

Description: In a series of experiments at LANSCE's WNR facility, 148Gdp roduction was measured for 600- and 800-MeV protons on tungsten, tantalum, and gold. These experiments used 3 pm thin W, Ta, and Au foils and 10 pm thin A1 activation foils, Spallation yields were determined for many short-lived and long-lived spallation products with these foils using gamma and alpha spectroscopy.
Date: January 1, 2002
Creator: Corzine, R. K. (R. Karen); Pitcher, E. J. (Eric J.); Devlin, M. J. (Matthew J.) & Hertel, N. E. (Nolan E.)
Partner: UNT Libraries Government Documents Department
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12th Workshop on Crystalline Silicon Solar Cell Materials and Processes: Extended Abstracts and Papers, August 11-14, 2002, Breckenridge, Colorado

Description: The 12th Workshop will provide a forum for an informal exchange of technical and scientific information between international researchers in the photovoltaic and relevant non-photovoltaic fields. Discussions will include various aspects of impurities and defects in silicon-their properties, the dynamics during processing, and their application for developing low-cost processes for manufacturing high-efficiency silicon solar cells. The workshop will emphasize some of the promising new technologies in Si solar cell fabrication that can lower PV energy costs and meet the production demands of the future. It will also provide an excellent opportunity for researchers, in private industry and at universities, to prioritize mutual needs for future collaborative research. Sessions and panel discussions will review recent advances in crystal growth, new cell structures, new processes and process characterization techniques, and manufacturing approaches suitable for future manufacturing demands . Some presentations will address recent technologies in the microelectronics field that may have a direct bearing on PV. The three-day workshop will consist of presentations by invited speakers, followed by discussion sessions. In addition, there will be two poster sessions presenting the latest research and development results.
Date: August 1, 2002
Creator: Sopori, B. L.
Partner: UNT Libraries Government Documents Department
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2001 environmental monitoring report for the Bettis Atomic Power Laboratory, West Mifflin Site

Description: The 2001 results for the Bettis-Pittsburgh radiological and nonradiological environmental monitoring programs are presented. The results demonstrate that the existing procedures ensured that releases to the environment during 2001 were in accordance with applicable Federal, State, County, and local regulations. Evaluation of the environmental data indicates that current operations at the Site continue to have no adverse effect on human health and the quality of the environment. A conservative assessment of radiation exposure to the general public as a result of Site operations demonstrates that the dose received by any member of the public was well below the most restrictive dose limits established by the Environmental Protection Agency, the Nuclear Regulatory Commission, and the U.S. Department of Energy. A risk assessment of potentially exposed populations to chemical residues in the environment at the Site demonstrates that any potential risk posed by these residues is much less than the risks encountered in normal everyday life.
Date: December 1, 2002
Partner: UNT Libraries Government Documents Department
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2001 NSLS Activity Report (National Synchrotron Light Source)

Description: The year 2001 has been another highly productive year at the NSLS, with over 2500 users, including 720 first time users, conducting nearly 1200 experiments in fields ranging from the life, materials, chemical, and environmental sciences to applied science and technology. An impressive array of highlights from this scientific activity is included in this Activity Report. They include the first demonstration of a direct structural probe of the superconducting ground state in the cuprates by utilizing anomalous soft x-ray resonance effects to selectively enhance the scattering from doped holes. Another highly significant result was the determination of the structure of the potassium channel membrane protein. This is especially significant as it provides insight into how the channel functions and how it selects a particular kind of ion. In the nanoscience area, small angle x-ray scattering measurements played an essential role in determining that preferential sequestering of tailored metal nanocrystals into a self-assembled lamellar diblock copolymer can produce high quality metallodielectric photonic bandgap structures, demonstrating the potential of these nanocomposites for photonic crystal engineering. The infrared microscopy program continued to yield noteworthy results, including an important study that characterized the types and abundances of organic materials in contaminated and uncontaminated sediments from the New York/New Jersey Harbor. These results will be useful in devising improved methods for the destruction or removal of these environmental contaminants.
Date: May 1, 2002
Creator: Corwin, M. A.
Partner: UNT Libraries Government Documents Department
open access

2001 SITE ENVIRONMENTAL REPORT

Description: THE SITE ENVIRONMENTAL REPORT FOR BROOKHAVEN NATIONAL LABORATORY FOR THE CALENDAR YEAR 2001, AS REQUIRED BY DOE ORDER 231.1.
Date: September 1, 2002
Creator: LABORATORY, BROOKHAVEN NATIONAL
Partner: UNT Libraries Government Documents Department
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2001 Wastewater Land Application Site Performance Reports for the Idaho National Engineering and Environmental Laboratory

Description: The 2001 Wastewater Land Application Site Performance Reports for the Idaho National Engineering and Environmental Laboratory describe site conditions for the facilities with State of Idaho Wastewater Land Application Permits. Permit-required monitoring data are summarized, and any permit exceedences or environmental impacts relating to the operation of any of the facilities during the 2001 permit year are discussed. Additionally, any special studies performed at the facilities, which related to the operation of the facility or application of the wastewater, are discussed.
Date: February 1, 2002
Creator: Meachum, Teresa Ray & Lewis, Michael George
Partner: UNT Libraries Government Documents Department
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2001 ''You Have the Power'' campaign [Federal Energy Management Program]. Final technical report

Description: The Tasks of 2001 ''You Have the Power'' campaign by the Federal Energy Management Program (FEMP) are: Task 1--Interagency Planning Meetings; Task 2--Ear Day Event; Task 3--Earth Day and Energy Awareness Month Activities; Task 4--Regional Target; Task 5--Outreach Tools and Campaign Products; Task 6--Private Sector Participation; Task 7--''You Have the Power'' on the FEMP Web Site; and Task 8--Effective Communications.
Date: January 1, 2002
Partner: UNT Libraries Government Documents Department
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The 2002 Farm Bill: Comparison of Commodity Support Provisions with the House and Senate Proposals, and Prior Law

Description: A new farm bill, the Farm Security and Rural Investment Act of 2002 (P.L. 107- 171), covering crop years 2002-2007, was signed into law May 13, 2002. The previous farm bill (now prior law) was the Federal Agriculture Improvement and Reform Act of 1996 (P.L. 104-127), popularly called the FAIR Act. Commodity support authority in the FAIR Act (Title I, Agricultural Market Transition Act (AMTA)) was set to expire after crop year 2002. This report provides a side-by-side comparison of prior law (AMTA), with most commodity support provisions of Title I of the new law, and the House and Senate farm bills.
Date: August 1, 2002
Creator: Womach, Jasper
Partner: UNT Libraries Government Documents Department
open access

2002 SNL ASCI Applications Software Engineering Assessment Report

Description: This document describes the 2002 SNL Accelerated Strategic Computing Initiative (ASCI) Applications Software Quality Engineering (SQE) Assessment and the assessment results. The primary purpose of the assessment was to establish the current state of software engineering practices within the SNL ASCI Applications Program.
Date: July 1, 2002
Creator: WILLIAMSON, CHARLES MICHAEL; OGDEN, HARVEY C. & BYLE, KATHLEEN A.
Partner: UNT Libraries Government Documents Department
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2nd Annual Los Alamos Plutonium Metal Standard Exchange Workshop : "preliminary" results

Description: The Rocky Flats Plutonium (Pu) Metal Sample Exchange program was conducted to insure the quality and intercomparability of measurements such as Pu assay, Pu isotopics, and impurity analyses. This program was discontinued in 1989 after more than 30 years. Los Alamos National Laboratory (LANL) has reestablished the Pu metal exchange program. During the first year, five DOE facilities, Argonne East, Argonne West, Livermore, Los Alamos, and New Brunswick Laboratory, Savannah River and the Atomic Weapons Establishment (AWE)' at Aldermaston are participating in the program. Plutonium metal samples are being prepared and distributed to the various sites primarily for destructive measurements for elemental concentration, isotopic abundance, and both metallic and nonmetallic impurity levels. The program is intended to provide independent verification of analytical measurement capability for each participating facility and to allow problems to be identified. Significants achievements in FY02 will be described. Results from category 1 elements and comparisons with Rocky Flats standards exchange metal historical data will also be presented. The roles and responsibilities of LANL and the external laboratories have been defined.
Date: January 1, 2002
Creator: Tandon, L. (Lav) & Slemmons, A. K. (Alice K.)
Partner: UNT Libraries Government Documents Department
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3D analysis of bainite morphologies and kinetics in alloy steels

Description: Serial sectioning and 3D reconstruction of austenite decomposition products were undertaken in bay-forming ternary steels to better understand their true morphologies in the bay region of their TTT diagrams. Jagged growth interfaces are revealed in allotriomorphic bainite formed at the bay in Fe-0.24C-4M0, contrasting with the idealized geometries often assumed when formulating growth models. This also has implications for experimental thickening kinetics measurments. Examination of the so-called 'degenerate' ferrite formed below the bay in Fe-Ox-6.3 W reveals that it is not degenerate at all, but rather has a Widmanstatten rod morphology which gives the appearance of degeneracy due to the multiplicity of ways that they can intersect a randomly-oriented plane of polish. Furthermore, these rods are grouped in packets posessing a common elongation direction, highlighting the crystallographic nature of their formation. The impact of these findings on the understanding of austenite decomposition in bayforming steels will be discussed.
Date: January 1, 2002
Creator: Hackenberg, R. E. (Robert E.); Nordstrom, D. P. (Dale P.) & Shiflet, G. J. (Gary J.)
Partner: UNT Libraries Government Documents Department
open access

AC losses in prototype multistrand conductors for warm dielectric cable designs

Description: We report on multiphase ac losses in four-layer prototype multi-strand conductors (PMCs) wound from EITS tape provided by American Superconductor Corporation. These conductors are prototypes warm dielectric cable designs, such as for the US Dept. of Energy's Superconductivity Partnership Initiative Project at Detroit Edison, We report on single phase 'two phaset'(no current in Ihe PMC but with an external ac magnetic field generated by the two normal Conductors arranged at the remaining corners of an equilateral triangle forming a three-phase configuration) ,and balanced three phase losses. Losses were also measured using a set of saddle coils to apply an ac magnetic field to the PMC. The losses were measured as a function of temperature, frequency, and current. We compare the losses for three PMCs, one (4LA) wound conventionally with equal pitch angles for all layers and the two others (4LB and 4LC) wound to achieve equal current distribution (UCD) among the layers, and thus lower singlephase losses in the operating region. In addition, 4LC was wound with a newer gcneration tape having a higher critical current. The PMC 4LC was found to have the lowest single, twophase, and three-phase losses.
Date: January 1, 2002
Creator: Willis, Jeffrey O.; Maley, Martin P.; Boening, Henirch J.; Coletta, Giacomo; Mele, Renata & Nassi, Marco
Partner: UNT Libraries Government Documents Department
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