3D unstructured mesh ALE hydrodynamics with the upwind discontinuous galerkin method (open access)

3D unstructured mesh ALE hydrodynamics with the upwind discontinuous galerkin method

The authors describe a numerical scheme to solve 3D Arbitrary Lagrangian-Eulerian (ALE) hydrodynamics on an unstructured mesh using a discontinuous Galerkin method (DGM) and an explicit Runge-Kutta time discretization. Upwinding is achieved through Roe's linearized Riemann solver with the Harten-Hyman entropy fix. For stabilization, a 3D quadratic programming generalization of van Leer's 1D minmod slope limiter is used along with a Lapidus type artificial viscosity. This DGM scheme has been tested on a variety of hydrodynamic test problems and appears to be robust making it the basis for the integrated 3D inertial confinement fusion modeling code (ICF3D). For efficient code development, they use C++ object oriented programming to easily separate the complexities of an unstructured mesh from the basic physics modules. ICF3D is fully parallelized using domain decomposition and the MPI message passing library. It is fully portable. It runs on uniprocessor workstations and massively parallel platforms with distributed and shared memory.
Date: May 7, 1999
Creator: Kershaw, D S; Milovich, J L; Prasad, M K; Shaw, M J & Shestakov, A I
Object Type: Article
System: The UNT Digital Library
Biofuel News, Spring 1999, Vol. 2 No. 2 (open access)

Biofuel News, Spring 1999, Vol. 2 No. 2

This issue of Biofuels News highlights DOE's ``Bridge to the Corn Ethanol Industry'' program and plans for commercializing corn stover conversion to ethanol.
Date: May 7, 1999
Creator: Poole, L.
Object Type: Book
System: The UNT Digital Library
BTS fact sheet: Ryan Homes and the Consortium for Advanced Residential Buildings (open access)

BTS fact sheet: Ryan Homes and the Consortium for Advanced Residential Buildings

Through Building America's unique collaboration process, Ryan Homes, the US Department of Energy, the National Renewable Energy Laboratory, and the Consortium for Advanced Residential Buildings worked together to identify ways to incorporate money-saving energy features throughout the Carborne house.
Date: May 7, 1999
Creator: unknown
Object Type: Book
System: The UNT Digital Library
Comparisons of cloud cover estimates and cloud fraction profiles from ARM's cloud-detecting instruments and GOES-8 data (open access)

Comparisons of cloud cover estimates and cloud fraction profiles from ARM's cloud-detecting instruments and GOES-8 data

The DOE's Atmospheric Radiation Measurement (ARM) Program employs both upward- and downward-looking remote-sensing instruments to measure the horizontal and vertical distributions of clouds across its Southern Great Plains (SGP) site. No single instrument is capable of completely determining these distributions over the scales of interest to ARM's Single Column Modeling (SCM) and Instantaneous Radiative Flux (IRF) groups; these groups embody the primary strategies through which ARM expects to achieve its objectives of developing and testing cloud formation parameterizations (USDOE, 1996). Collectively, however, the data from ARM's cloud-detecting instruments offer the potential for such a three-dimensional characterization. Data intercomparisons, like the ones illustrated in this paper, are steps in this direction. Examples of some initial comparisons, involving satellite, millimeter cloud radar, whole sky imager and ceilometer data, are provided herein. that many of the lessons learned can later be adapted to cloud data at the Boundary and Extended Facilities. Principally, we are concerned about: (1) the accuracy of various estimates of cloud properties at a single point, or within a thin vertical column, above the CF over time, and (2) the accuracy of various estimates of cloud properties over the Cloud and Radiation Testbed (CART) site, which can then be reduced …
Date: May 7, 1999
Creator: Krueger, S K & Rodriguez, D
Object Type: Article
System: The UNT Digital Library
Department of Energy Workforce Reduction: Community Assistance Can Be Better Targeted (open access)

Department of Energy Workforce Reduction: Community Assistance Can Be Better Targeted

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a legislative requirement, GAO reviewed the Department of Energy's (DOE) community assistance program for minimizing the impact of downsizing its contractor workforce, focusing on: (1) how much funding DOE had committed to spend and spent in support of its worker and community assistance program for fiscal years (FY) 1994 through 1998; (2) who received benefits during FY 1997 and FY 1998; (3) comparing DOE's separation benefits with the benefit packages of other federal and nonfederal organizations; and (4) what effect DOE's criteria had on determining which communities received assistance."
Date: May 7, 1999
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Electroweak Results from the SLD Experiment (open access)

Electroweak Results from the SLD Experiment

We present an overview of the electroweak physics program of the SLD experiment at the Stanford Linear Accelerator Center (SLAC). A data sample of 550K Z{sup 0} decays has been collected. This experiment utilizes a highly polarized electron beam, a small interaction volume, and a very precise pixel vertex detector. It is the first experiment at a linear electron collider. We present a preliminary result for the weak mixing angle, sin{sup 2}({theta}{sub W}{sup eff}) = 0.23110 {+-} 0.00029. We also present a preliminary result for the parity violating parameter, A{sub b} = 0.898 {+-} 0.029. These measurements are used to test for physics beyond the Standard Model.
Date: May 7, 1999
Creator: Woods, Michael B
Object Type: Report
System: The UNT Digital Library
Environmental management of assembled chemical weapons assessment program. (open access)

Environmental management of assembled chemical weapons assessment program.

Environmental planning and management was an integral part of the ACWA Program planning process. To ensure that environmental protection issues could be addressed expeditiously and not delay the demonstrations, the PMACWA scaled the technology demonstrations such that simplified regulatory processes and existing research and development facilities could be used. The use of enclosed facilities for the demonstrations prevents any uncontrolled discharges to the environment and made it possible to conduct environmental assessments relatively quickly. The PMACWA also arranged for public briefings to ease any community concerns over the operations with chemical weapons. These steps precluded regulatory and community resistance to the ACWA activities. The cooperation of the regulators and stakeholders has been a key element in enabling the ACWA Program to move with the speed that it has to date. Technology demonstrations are currently underway and are scheduled to be completed in late May 1999. The data collected during these demonstrations will be used to prepare and submit a summary report to Congress by August 1999. The challenge continues for the ACWA management to guide the demonstrations to completion and to plan for possible pilot testing. As the scale of the ACWA facilities increase in size, the ease of reduced …
Date: May 7, 1999
Creator: Frey, G.; Mohrman, G. & Templin, B. R.
Object Type: Article
System: The UNT Digital Library
Feasibility study for analyzing plasma-aerodynamic effects (open access)

Feasibility study for analyzing plasma-aerodynamic effects

The purpose of this feasibility study was to conduct preliminary modeling to elucidate the mechanisms responsible for the effects observed in the Air Force Research Laboratory (AFRL) shock tube experiment. It was assumed that the plasma is simply a region of gas in the shock tube that has a higher gas temperature. Computational fluid dynamics (CFD) calculations were performed to simulate the propagation of a shock wave through the tube, using the same parameters in the experiment. Both 1- D and 3-D CFD calculations were performed to determine which effects can be explained simply by axial temperature gradients and which effects require the presence of radial temperature gradients. Discharge plasma physics calculations of a longitudinal glow discharge were then used to establish if the electrical currents used in the experiment are consistent with the gas temperature distributions that are necessary to explain the observed effects.
Date: May 7, 1999
Creator: Penetrante, B & Sherohman, J
Object Type: Report
System: The UNT Digital Library
Federally Chartered Corporation: Review of the Financial Statement Audit Report for the United States Olympic Committee for 1997 (open access)

Federally Chartered Corporation: Review of the Financial Statement Audit Report for the United States Olympic Committee for 1997

Correspondence issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed the audit report covering the financial statements of the United States Olympic Committee for the year ended December 31, 1997, focusing on whether the audit report complied with the financial reporting requirements of the law."
Date: May 7, 1999
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Federally Chartered Corporation: Review of the Financial Statement Audit Report for the Women's Army Corps Veterans Association for Fiscal Year 1998 (open access)

Federally Chartered Corporation: Review of the Financial Statement Audit Report for the Women's Army Corps Veterans Association for Fiscal Year 1998

Correspondence issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed the audit report covering the financial statements of the Women's Army Corps Veterans Association for the fiscal year June 30, 1998, focusing on whether the audit report complied with the financial reporting requirements of the law."
Date: May 7, 1999
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Final report, DOE grant DE-FG02-93ER61691.A000. Validation of soil moisture in GCMs--AMIP diagnostic subproject 11, September 1, 1993 - August 31, 1998 (open access)
Formation of Mesostructured Nanoparticles through Self-Assembly and Aerosol Process (open access)

Formation of Mesostructured Nanoparticles through Self-Assembly and Aerosol Process

Silica nanoparticles exhibiting hexagonal, cubic, and vesicular mesostructures have been prepared using aerosol assisted, self-assembled process. This process begins with homogennous aerosol droplets containing silica source, water, ethanol, and surfactant, in which surfactant concentration is far below the critical micelle concentration (cmc). Solvent evaporation enriches silica and surfactant inducing interfacial self-assembly confined to a spherical aerosol droplet and results in formation of completely solid, ordered spherical particles with stable hexagonal, cubic, or vesicular mesostructures.
Date: May 7, 1999
Creator: Brinker, C. Jeffrey; Fan, Hongyou; Lu, Yunfeng; Rieker, Thomas; Stump, Arron & Ward, Timothy L.
Object Type: Article
System: The UNT Digital Library
Fourier mode analysis of slab-geometry transport iterations in spatially periodic media (open access)

Fourier mode analysis of slab-geometry transport iterations in spatially periodic media

We describe a Fourier analysis of the diffusion-synthetic acceleration (DSA) and transport-synthetic acceleration (TSA) iteration schemes for a spatially periodic, but otherwise arbitrarily heterogeneous, medium. Both DSA and TSA converge more slowly in a heterogeneous medium than in a homogeneous medium composed of the volume-averaged scattering ratio. In the limit of a homogeneous medium, our heterogeneous analysis contains eigenvalues of multiplicity two at ''resonant'' wave numbers. In the presence of material heterogeneities, error modes corresponding to these resonant wave numbers are ''excited'' more than other error modes. For DSA and TSA, the iteration spectral radius may occur at these resonant wave numbers, in which case the material heterogeneities most strongly affect iterative performance.
Date: May 7, 1999
Creator: Larsen, E W & Zika, M R
Object Type: Article
System: The UNT Digital Library
General Aviation Airports: Unauthorized Land Use Highlights Need for Improved Oversight and Enforcement (open access)

General Aviation Airports: Unauthorized Land Use Highlights Need for Improved Oversight and Enforcement

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a legislative requirement, GAO provided information on: (1) the Federal Aviation Administration's (FAA) monitoring of general aviation airports' compliance with federal land-use requirements; and (2) FAA's use of enforcement tools to resolve cases of noncompliance."
Date: May 7, 1999
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
International Energy Agency: How the Agency Prepares Its World Oil Market Statistics (open access)

International Energy Agency: How the Agency Prepares Its World Oil Market Statistics

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on: (1) how the International Energy Agency (IEA) prepares its world oil market statistics; and (2) what accounted for the missing barrels in IEA's historical world oil market statistics in 1998."
Date: May 7, 1999
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Lifetime studies at the APS. (open access)

Lifetime studies at the APS.

The studies presented in this note are focused on the lifetime characterization with positrons for the symmetrical low {beta}{sub y} lattice. Before switching back to electrons, detailed lifetime studies were performed in order to gather data that could be compared to similar ones with electrons, the ultimate goal being to define a model that could be used to predict lifetimes. The report is divided into three parts: simulations to allow decoupling of the different contributions to the lifetime; review of the experimental conditions and related problems; and analysis of the data and discussion of the limitations.
Date: May 7, 1999
Creator: Ropert, A.
Object Type: Report
System: The UNT Digital Library
Molecular Environmental Science and Synchrotron Radiation Facilities An Update of the 1995 DOE-Airlie Report on Molecular Environmental Science (open access)

Molecular Environmental Science and Synchrotron Radiation Facilities An Update of the 1995 DOE-Airlie Report on Molecular Environmental Science

This workshop was requested by Dr. Robert Marianelli, Director of the DOE-BES Chemical Sciences Division, to update the findings of the Workshop on Molecular Environmental Sciences (MES) held at Airlie, VA, in July 1995. The Airlie Workshop Report defined the new interdisciplinary field referred to as Molecular Environmental Science (MES), reviewed the synchrotron radiation methods used in MES research, assessed the adequacy of synchrotron radiation facilities for research in this field, and summarized the beam time requirements of MES users based on a national MES user survey. The objectives of MES research are to provide information on the chemical and physical forms (speciation), spatial distribution, and reactivity of contaminants in natural materials and man-made waste forms, and to develop a fundamental understanding of the complex molecular-scale environmental processes, both chemical and biological, that affect the stability, transformations, mobility, and toxicity of contaminant species. These objectives require parallel studies of ''real'' environmental samples, which are complicated multi-phase mixtures with chemical and physical heterogeneities, and of simplified model systems in which variables can be controlled and fundamental processes can be examined. Only by this combination of approaches can a basic understanding of environmental processes at the molecular-scale be achieved.
Date: May 7, 1999
Creator: Bargar, John R
Object Type: Report
System: The UNT Digital Library
Motor Challenge Energy Matters, May 1999 (open access)

Motor Challenge Energy Matters, May 1999

The May issue of Energy Matters (formerly Turning Point) features articles on motor, steam, and compressed air systems management. One article explains how chemical treatment can improve boiler system efficiency; another discusses the importance of data logging to assess compressed air system performance. A feature article describes motor system upgrades at Blue Circle Aggregates, a Georgia quarry, which resulted after a no-cost assessment by one of DOE's Industrial Assessment Centers. This issue includes an 8-page special supplement devoted to steam system efficiency.
Date: May 7, 1999
Creator: Ericksen, E.
Object Type: Book
System: The UNT Digital Library
National Laboratories: DOE Needs to Assess the Impact of Using Performance-Based Contracts (open access)

National Laboratories: DOE Needs to Assess the Impact of Using Performance-Based Contracts

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed the Department of Energy's (DOE) progress in implementing performance-based contracting at its national laboratories, focusing on: (1) the status of performance-based contracting in DOE's national laboratory contracts; and (2) DOE's efforts to determine the impact of performance-based contracting."
Date: May 7, 1999
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
"A Novel Synthesis of Zeolite W..." (open access)

"A Novel Synthesis of Zeolite W..."

Zeolite W has been synthesized using organometallic silicon and aluminum precursors in two hydrothermal systems: organocation containing and organocation-free. The reaction using the organocation yielded a fully crystalline, relatively uniform crystal size product, with no organic molecules occluded in the pores. In contrast, the product obtained from an identical reaction, except for the absence of the organocation, contained amorphous as well as crystalline material and the crystalline phase showed a large diversity of both crystal size and morphology. The use of organometallic precursors, either with or without an organocation, allows for the crystallization of the MER framework at much lower 0H/Si02 and (K+ Na - Al)/Si ratios than is typical of inorganic systems. The reaction products were characterized by XRD, SEM, EDS, and thermal analyses.
Date: May 7, 1999
Creator: Nenoff, Tina M. & Thoma, Steven G.
Object Type: Article
System: The UNT Digital Library
Results Act: Observations on the Department of Transportation's Fiscal Year 2000 Performance Plan (open access)

Results Act: Observations on the Department of Transportation's Fiscal Year 2000 Performance Plan

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on the Department of Transportation's (DOT) performance plan for fiscal year (FY) 2000, focusing on: (1) the usefulness of DOT's plan in providing a clear picture of intended performance across the Department; (2) the strategies and resources that DOT will use to achieve its goals; and (3) whether DOT's performance information will be credible."
Date: May 7, 1999
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Self-effect in expanding electron beam plasma (open access)

Self-effect in expanding electron beam plasma

An analytical model of plasma flow from a metal plate hit by an intense, pulsed, electron beam aims to bridge the gap between radiation-hydrodynamics simulations and experiments, and to quantify the self-effect of the electron beam penetrating the flow. Does the flow disrupt the tight focus of the initial electron bunch, or later pulses in a train? This work aims to model the spatial distribution of plasma speed, density, degree of ionization, and magnetization to inquire. The initial solid density, several eV plasma expands to 1 cm and 10{sup {minus}4} relative density by 2 {micro}s, beyond which numerical simulations are imprecise. Yet, a Faraday cup detector at the ETA-II facility is at 25 cm from the target and observes the flow after 50 {micro}s. The model helps bridge this gap. The expansion of the target plasma into vacuum is so rapid that the ionized portion of the flow departs from local thermodynamic equilibrium. When the temperature (in eV) in a parcel of fluid drops below V{sub i} x [(2{gamma} - 2)/(5{gamma} + 17)], where V{sub i} is the ionization potential of the target metal (7.8 eV for tantalum), and {gamma} is the ratio of specific heats (5/3 for atoms), then …
Date: May 7, 1999
Creator: Garcia, M
Object Type: Article
System: The UNT Digital Library
Syntheses and Structures of the Open-Framework Phases (CH(3)NH(3))(3).Zn(4)O(AsO(4))(3) and (CH(3)NH(3))(3).Zn(4)O(PO(4))(3) Related to the M(3)Zn(4)O(XO(4)(3).nH(2)O Family (open access)

Syntheses and Structures of the Open-Framework Phases (CH(3)NH(3))(3).Zn(4)O(AsO(4))(3) and (CH(3)NH(3))(3).Zn(4)O(PO(4))(3) Related to the M(3)Zn(4)O(XO(4)(3).nH(2)O Family

The solution-mediated syntheses and single crystal structures of (CH<sub>3</sub>NH<sub>3</sub>)<sub>3</sub>&middot;Zn<sub>4</sub>0(AsO<sub>4</sub>)<sub>3</sub> and (CH<sub>3</sub>NH<sub>3</sub>)<sub>3</sub>&middot;Zn<sub>4</sub>O(P0<sub>4</sub>)<sub>3</sub> are reported. These compounds are built up from vertex-sharing three-dimensional Zn0<sub>4</sub> + AsO<sub>4</sub>/P0<sub>4</sub> tetrahedral frameworks encapsulating methylammonium cations in three-dimensional channel systems. These phases are closely related to the zeolite- like M<sub>3</sub>Zn<sub>4</sub>O(XO<sub>4</sub>)<sub>3</sub>&middot;nH<sub>2</sub>O family of phases. Crystal data for (CH<sub>3</sub>NH<sub>3</sub>)<sub>3</sub>&middot;Zn<sub>4</sub>0(AsO<sub>4</sub>)<sub>3</sub>, M, = 790.47, monoclinic, space group P2<sub>1</sub> (No. 4), a = 7.814 (3)&Aring;, b = 15.498 (6)&Aring;, c = 7.815 (3) &Aring;, {beta} = 92.91 (2)0, V = 945.1 (9) &Aring;<sup>3</sup>, Z = 2, R(F) = 3.01%, R<sub>W</sub>(F) = 3.98% (2301 reflections, 236 parameters). Crystal data for (CH<sub>3</sub>NH<sub>3</sub>)<sub>3</sub>&middot;Zn<sub>4</sub>0(P0<sub>4</sub>)<sub>3</sub>: M, = 658.63, monoclinic, space group P2<sub>1</sub> (No. 4), a = 7.6569 (5) &Aring;, b = 15.241 (1)&Aring;, c= 7.6589 (5) &Aring;, {beta} = 92.740 (1)0, V= 892.7 (5) &Aring;<sup>3</sup>, Z = 2, R(F)= 8.07%, R<sub>W</sub>(F)= 9.60% (2694 reflections, 106 parameters).
Date: May 7, 1999
Creator: Chavez, Alejandra V.; Harrison, William T.A.; Nenoff, Tina M. & Phillips, Mark L.F.
Object Type: Article
System: The UNT Digital Library
Synthesis, Characterization and Ion Exchange of New Na/Nb/M(4+)/O/H(2)O(M=Ti,Zr) Phases (open access)

Synthesis, Characterization and Ion Exchange of New Na/Nb/M(4+)/O/H(2)O(M=Ti,Zr) Phases

Due to the vast diversity of chemical media in which metal separations are executed, a wide range of ion separation materials are employed. This results in an ongoing effort to discover new phases with novel ion exchange properties. We present here the synthesis of a novel class of thermally and chemically stable microporous, niobate-based materials. Ion exchange studies show these new phases are highly selective for Sr<sup>2+</sup> and other bivalent metals.
Date: May 7, 1999
Creator: Nenoff, Tina M. & Nyman, May
Object Type: Article
System: The UNT Digital Library