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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
A 3-D model of superfluid helium suitable for numerical analysis (open access)

A 3-D model of superfluid helium suitable for numerical analysis

The two-fluid description is a very successful phenomenological representation of the properties of Helium II. A 3-D model suitable for numerical analysis based on the Landau-Khalatnikov description of Helium II is proposed. In this paper we introduce a system of partial differential equations that is both complete and consistent as well as practical, to be used for a 3-D solution of the flow of Helium II. The development of a 3-D numerical model for Helium II is motivated by the need to validate experimental results obtained by observing the normal component velocity distribution in a Helium II thermal counter-flow using the Particle Image Velocimetry (PIV) technique.
Date: January 1, 2008
Creator: Darve, C.; U., /Fermilab /Northwestern; Patankar, N.A.; U., /Northwestern; Van Sciver, S.W. & Lab., /Natl. High Mag. Field
Object Type: Article
System: The UNT Digital Library
A 3-D ray-trace model for an AMR code on distributed processors (open access)

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

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.)
Object Type: Article
System: The UNT Digital Library
21-kW Thin-Film PV Technology Validation -- An NREL/Solar Energy Centre of India MOU Cooperative Project (open access)

21-kW Thin-Film PV Technology Validation -- An NREL/Solar Energy Centre of India MOU Cooperative Project

This paper summarizes findings during a one-week (27-31 October 2003) site visit to the Thin-Film Technology Test Bed at India's Solar Energy Centre (SEC) near New Delhi. The U.S. and Indian governments signed a Memorandum of Understanding in March 2000 to undertake a 50-50 cost-shared 21-kW thin-film PV technology validation project to evaluate the performance of thin-film photovoltaic (PV) modules under Indian climatic conditions. This project benefits Indian researchers by giving them experience with cost-effective PV materials, and it benefits the United States because data will be sent to the appropriate U.S. thin-film PV manufacturers for evaluation and analysis. During the visit, NREL personnel engaged in technical discussions regarding thin-film PV technologies with Ministry of Non-Conventional Energy Sources engineers and scientists. Issues included inspecting the newly constructed arrays, discussing better methods of electrically loading the PV arrays, taking I-V traces, and gathering baseline I-V data.
Date: January 1, 2005
Creator: McNutt, P. F. & Ullal, H. S.
Object Type: Article
System: The UNT Digital Library
24-Channel Geophone Array for Horizontal or Vertical Boreholes Quarterly Technical Report: July-September 2002 (open access)

24-Channel Geophone Array for Horizontal or Vertical Boreholes Quarterly Technical Report: July-September 2002

This report describes the technical progress on a project to design and construct a multichannel 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: January 1, 2003
Creator: Westman, Erik C.
Object Type: Report
System: The UNT Digital Library
25 years of technical advances in RFQ accelerators (open access)

25 years of technical advances in RFQ accelerators

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.)
Object Type: Article
System: The UNT Digital Library
A 50 kV solid state multipulse kicker modulator (open access)

A 50 kV solid state multipulse kicker modulator

Performance requirements, design concepts, and test results for a prototype multipulse kicker modulator based on solid-state switches and a voltage-adding transformer topology are described. Tape-wound cores are stacked to form the transformer primary windings and a cylindrical pipe that passes through the circular inner diameters of the cores serves as the secondary winding of the step-up transformer. Boards containing MOSFET switches, trigger circuitry, and energy-storage capacitors plug into the core housings. A 50 kV prototype modulator that meets most of the facility requirements has been designed, fabricated, and tested at LLNL. More recent work has been concerned with designing and testing cores and boards with the full volt-second capability needed for 24-pulse operation. Results of the 50 kV prototype tests, preliminary tests of the full-volt-second cores and boards, and future development needs are described.
Date: January 1, 2003
Creator: Walstrom, P. L. (Peter L.) & Cook, E. G. (Edward G.)
Object Type: Article
System: The UNT Digital Library
56 MHZ Cavity Prototype Measurements (open access)

56 MHZ Cavity Prototype Measurements

N/A
Date: January 1, 2009
Creator: H., Hahn & Choi, E.
Object Type: Report
System: The UNT Digital Library
60 years of great science [Oak Ridge National Laboratory] (open access)

60 years of great science [Oak Ridge National Laboratory]

This issue highlights Oak Ridge National Laboratory's contributions in more than 30 areas of research and related activities during the past 60 years and provides glimpses of current activities that are carrying on this heritage.
Date: January 1, 2003
Creator: unknown
Object Type: Report
System: The UNT Digital Library
148-Gd cross section measurements for accelerator target facilities (open access)

148-Gd cross section measurements for accelerator target facilities

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.)
Object Type: Article
System: The UNT Digital Library
488-D Ash Basin Vegetative Cover Treatibility Study (open access)

488-D Ash Basin Vegetative Cover Treatibility Study

The 488-D Ash Basin is an unlined containment basin that received ash and coal reject material from the operation of a powerhouse at the USDOE's Savannah River Site, SC. They pyretic nature of the coal rejects has resulted in the formation of acidic drainage (AD), which has contributed to groundwater deterioration and threatens biota in down gradient wetlands. Establishment of a vegetative cover was examined as a remedial alternative for reducing AD generation within this system by enhanced utilization of rainwater and subsequent non-point source water pollution control. The low nutrient content, high acidity, and high salinity of the basin material, however, was deleterious to plant survivability. As such, studies to identify suitable plant species and potential adaptations, and pretreatment techniques in the form of amendments, tilling, and/or chemical stabilization were needed. A randomized block design consisting of three subsurface treatments (blocks) and five duplicated surface amendments (treatments) was developed. One hundred inoculated pine trees were planted on each plot. Herbaceous species were also planted on half of the plots in duplicated 1-m2 beds. After two growing seasons, deep ripping, subsurface amendments and surface covers were shown to be essential for the successful establishment of vegetation on the basin. This …
Date: January 1, 2003
Creator: Barton, Christopher; Marx, Don; Blake, John; Adriano, Domy; Koo, Bon-Jun & Czapka, Stephen
Object Type: Report
System: The UNT Digital Library
915-MHz Radar Wind Profiler (915RWP) Handbook (open access)

915-MHz Radar Wind Profiler (915RWP) Handbook

The 915 MHz radar wind profiler/radio acoustic sounding system (RWP/RASS) measures wind profiles and backscattered signal strength between (nominally) 0.1 km and 5 km and virtual temperature profiles between 0.1 km and 2.5 km. It operates by transmitting electromagnetic energy into the atmosphere and measuring the strength and frequency of backscattered energy. Virtual temperatures are recovered by transmitting an acoustic signal vertically and measuring the electromagnetic energy scattered from the acoustic wavefront. Because the propagation speed of the acoustic wave is proportional to the square root of the virtual temperature of the air, the virtual temperature can be recovered by measuring the Doppler shift of the scattered electromagnetic wave.
Date: January 1, 2005
Creator: Coulter, R.
Object Type: Report
System: The UNT Digital Library
13th Workshop on Crystalline Silicon Solar Cell Materials and Processes: Summary Discussion, 10-13 August 2003, Vail, Colorado (open access)

13th Workshop on Crystalline Silicon Solar Cell Materials and Processes: Summary Discussion, 10-13 August 2003, Vail, Colorado

The 13th Workshop discussion sessions addressed recent progress, critical issues in implementing new technologies, and the role of fundamental R&D in the growing PV industry. For the first time, we included a rump session, which was held on Sunday evening, August 10. This session included a panel of representatives, from various photovoltaic companies, who led a discussion of''R&D Challenges in Si PV.'' A special poster/presentation session was held on Monday evening, August 11, in which NREL/DOE subcontractors highlighted their results of research performed during the current subcontract period. This session served as a subcontract review. The workshop offered special sessions to discuss: (1) High-Efficiency Si Solar Cells, which reviewed progress made in implementing high-efficiency Si solar cell fabrication processes in the manufacturing environment; (2) Advanced Processing, as future potential approaches for making Si solar cells; (3) Commercial Issues, which addressed basic understanding behind recent processes that have been used by the PV industry; and (4) Automation and Equipment, to address capabilities and requirements of new manufacturing equipment.
Date: January 1, 2004
Creator: Sopori, B.; Sinton, R.; Tan, T. & Swanson, D.
Object Type: Article
System: The UNT Digital Library
16th ANS Topical Meeting on the Technology of Fusion Energy (open access)

16th ANS Topical Meeting on the Technology of Fusion Energy

None
Date: January 1, 2004
Creator: Kulcinski, Gerald
Object Type: Article
System: The UNT Digital Library
1Surface structure of cleaved (001) USB2 single crystal surface (open access)

1Surface structure of cleaved (001) USB2 single crystal surface

We have achieved what we believe to be the first atomic resolution STM images for a uranium compound USb2 taken at room temperature. The a, b, and c lattice parameters in the images confirm that the tetragonal USb2crystals cleave on the (00 I) basal plane as expected. Our calculations indicate a symmetric cut between Sb planes to be the most favorable cleavage plane and U atoms to be responsible for most ofthe density of states measured by STM. Since the spacing between Sb atoms and between U atoms is the same, STM topography only cannot unambiguously identify the surface atom species.
Date: January 1, 2009
Creator: Chen, Shao-ping
Object Type: Article
System: The UNT Digital Library
2001 ''You Have the Power'' campaign [Federal Energy Management Program]. Final technical report (open access)

2001 ''You Have the Power'' campaign [Federal Energy Management Program]. Final technical report

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
Creator: unknown
Object Type: Report
System: The UNT Digital Library
2004 Annual Summary Report for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site, Nye County, Nevada (open access)

2004 Annual Summary Report for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site, Nye County, Nevada

The Maintenance Plan for the Performance Assessments and Composite Analyses for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site (Bechtel Nevada, 2000) requires an annual review to assess the adequacy of the performance assessments (PAs) and composite analyses (CAs) for each of the facilities, and reports the results in an annual summary report to the U.S. Department of Energy Headquarters. The Disposal Authorization Statements for the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) also require that such reviews be made and that secondary or minor unresolved issues be tracked and addressed as part of the maintenance plan (U.S. Department of Energy [DOE]). The U.S. Department of Energy National Nuclear Security Administration Nevada Site Office performed annual reviews in fiscal year (FY) 2004 by evaluating operational factors and research results that impact the continuing validity of the PA and CA results. This annual summary report presents data and conclusions from the FY 2004 review, and determines the adequacy of the PAs and CAs. Operational factors, such as the waste form and containers, facility design, waste receipts, closure plans, as well as monitoring results and research and development (R&D) activities were reviewed …
Date: January 1, 2005
Creator: Yucel, Vefa
Object Type: Report
System: The UNT Digital Library
2004 research briefs :Materials and Process Sciences Center. (open access)

2004 research briefs :Materials and Process Sciences Center.

This report is the latest in a continuing series that highlights the recent technical accomplishments associated with the work being performed within the Materials and Process Sciences Center. Our research and development activities primarily address the materials-engineering needs of Sandia's Nuclear-Weapons (NW) program. In addition, we have significant efforts that support programs managed by the other laboratory business units. Our wide range of activities occurs within six thematic areas: Materials Aging and Reliability, Scientifically Engineered Materials, Materials Processing, Materials Characterization, Materials for Microsystems, and Materials Modeling and Simulation. We believe these highlights collectively demonstrate the importance that a strong materials-science base has on the ultimate success of the NW program and the overall DOE technology portfolio.
Date: January 1, 2004
Creator: Cieslak, Michael J.
Object Type: Report
System: The UNT Digital Library
2006 Catalysis Gordon Conference (open access)

2006 Catalysis Gordon Conference

This Report is about Gordon Conference on Catalysis which was held at Colbey-Sawyer College.
Date: January 1, 2006
Creator: Davis, Robert & Gray, Nancy Ryan
Object Type: Article
System: The UNT Digital Library
2006 Update of Business Downtime Costs (open access)

2006 Update of Business Downtime Costs

The objective of this paper is to assess the downtime cost of power outages to businesses in the commercial and industrial sectors, updating and improving upon studies that have already been published on this subject. The goal is to produce a study that, relative to existing studies, (1) applies to a wider set of business types (2) reflects more current downtime costs, (3) accounts for the time duration factor of power outages, and (4) includes data on the costs imposed by real outages in a well-defined market. This study examines power outage costs in 11 commercial subsectors and 5 industrial subsectors, using data on downtime costs that was collected in the 1990's. This study also assesses power outage costs for power outages of 20 minutes, 1 hour, and 4 hours duration. Finally, this study incorporates data on the costs of real power outages for two business subsectors. However, the current limited state of data availability on the topic of downtime costs means there is room to improve upon this study. Useful next steps would be to generate more recent data on downtime costs, data that covers outages shorter than 20 minutes duration and longer than 4 hours duration, and more …
Date: January 1, 2007
Creator: Hinrichs, Doug & Goggin, Michael
Object Type: Report
System: The UNT Digital Library
2007 Annual Summary Report for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site, Nye County, Nevada (open access)

2007 Annual Summary Report for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site, Nye County, Nevada

This report summarizes the results of an annual review of conditions affecting the operation of the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) and a determination of the continuing adequacy of the performance assessments (PAs) and composite analyses (CAs). The Area 5 RWMS PA documentation consists of the original PA (Shott et al., 1998), referred to as the 1998 Area 5 RWMS PA and supporting addenda (Bechtel Nevada [BN], 2001b; 2006a). The Area 5 RWMS CA was issued as a single document (BN, 2001a) and has a single addendum (BN, 2001c). The Area 3 PA and CA were issued in a single document (Shott et al., 2000). The Maintenance Plan for the PAs and CAs (National Security Technologies, LLC [NSTec], 2006) and the Disposal Authorization Statements (DASs) for the Area 3 and 5 RWMSs (U.S. Department of Energy [DOE], 2000; 2002) require preparation of an annual summary and a determination of the continuing adequacy of the PAs and CAs. The annual summary report is submitted to DOE Headquarters. Following the annual report format in the DOE PA/CA Maintenance Guide (DOE, 1999), this report presents the annual summary for the PAs in Section 2.0 and the CAs in …
Date: January 1, 2008
Creator: National Security Technologies, LLC
Object Type: Report
System: The UNT Digital Library
2007 Inorganic Reaction Mechanisms Gordon Research Conference-February 18-23 (open access)

2007 Inorganic Reaction Mechanisms Gordon Research Conference-February 18-23

This conference focuses on kinetic, mechanistic, and thermodynamic studies of reactions that play a role in fields as diverse as catalysis, energy, bioinorganic chemistry, green chemistry, organometallics, and activation of small molecules (oxygen, nitrogen, carbon monoxide, carbon dioxide, alkanes). Participants from universities, industry, and national laboratories present results and engage in discussions of pathways, intermediates, and outcome of various reactions of inorganic, organic, coordination, organometallic, and biological species. This knowledge is essential for rational development and design of novel reactions, compounds, and catalysts.
Date: January 1, 2008
Creator: Gray, Andreja Bakac Nancy Ryan
Object Type: Article
System: The UNT Digital Library
2008 Wind Energy Projects, Wind Powering America (Poster) (open access)

2008 Wind Energy Projects, Wind Powering America (Poster)

The Wind Powering America program produces a poster at the end of every calendar year that depicts new U.S. wind energy projects. The 2008 poster includes the following projects: Stetson Wind Farm in Maine; Dutch Hill Wind Farm in New York; Grand Ridge Wind Energy Center in Illinois; Hooper Bay, Alaska; Forestburg, South Dakota; Elbow Creek Wind Project in Texas; Glacier Wind Farm in Montana; Wray, Colorado; Smoky Hills Wind Farm in Kansas; Forbes Park Wind Project in Massachusetts; Spanish Fork, Utah; Goodland Wind Farm in Indiana; and the Tatanka Wind Energy Project on the border of North Dakota and South Dakota.
Date: January 1, 2009
Creator: unknown
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