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Chemicals and excess materials disposition during facility deactivation as a means of pollution prevention

Description: This paper presents several innovative and common sense approaches to pollution prevention that have been employed during facility deactivation at the Hanford Site in South Central Washington. It also presents several pollution prevention principles applicable to other projects. Innovative pollution prevention ideas employed at the Hanford site during facility deactivation included: (1) Recycling more than 185,000 gallons of radioactively contaminated nitric acid by sending it to an operating n… more
Date: May 28, 1998
Creator: Godfrey, S. D.
Partner: UNT Libraries Government Documents Department
open access

Less minimal supersymmetric standard model

Description: Most of the phenomenological studies of supersymmetry have been carried out using the so-called minimal supergravity scenario, where one assumes a universal scalar mass, gaugino mass, and trilinear coupling at M{sub GUT}. Even though this is a useful simplifying assumption for phenomenological analyses, it is rather too restrictive to accommodate a large variety of phenomenological possibilities. It predicts, among other things, that the lightest supersymmetric particle (LSP) is an almost pure … more
Date: March 28, 1998
Creator: de Gouvea, Andre; Friedland, Alexander & Murayama, Hitoshi
Partner: UNT Libraries Government Documents Department
open access

The Tunnel Sealing Experiment: An In Situ Demonstration of Technologies for Vault Sealing

Description: Two bulkheads, one composed of high performance concrete and the other of highly compacted sand-bentonite material, have been constructed in a tunnel in unfractured granite rock at the Underground Research Laboratory. The Tunnel Sealing Experiment will characterize the performance of the two bulkheads under applied hydraulic pressures. The chamber between the two bulkheads will be pressurized to approximately 4 MPa, a value representative of the ambient pore pressures in the rock at a depth of … more
Date: October 28, 1998
Creator: Chandler, N.; Cournut, A.; Dixon, D.; Gray, M.; Hara, K. & Tillerson, J.
Partner: UNT Libraries Government Documents Department
open access

Postirradiation examination of high-density uranium alloy dispersion fuels.

Description: Two irradiation test vehicles, designated RERTR-1 and RERTR-2, were inserted into the Advanced Test Reactor in Idaho in August 1997. These tests were designed to obtain irradiation performance information on a variety of potential new, high-density uranium alloy dispersion fuels, including U-10Mo,U-8Mo, U-6Mo, U-4Mo, U-9Nb-3Zr, U-6Nb-4Zr, U-5Nb-3Zr, U-6Mo-1Pt, U-6Mo-0.6Ru and U-10Mo-0.05Sn; the intermetallic compounds U{sub 2}Mo and U{sub 3}Si{sub 2} were also included in the fuel test matrix. … more
Date: October 28, 1998
Creator: Hayes, S. L.
Partner: UNT Libraries Government Documents Department
open access

EXAFS and principal component analysis : a new shell game.

Description: The use of principal component (factor) analysis in the analysis EXAFS spectra is described. The components derived from EXAFS spectra share mathematical properties with the original spectra. As a result, the abstract components can be analyzed using standard EXAFS methodology to yield the bond distances and other coordination parameters. The number of components that must be analyzed is usually less than the number of original spectra. The method is demonstrated using a series of spectra from … more
Date: October 28, 1998
Creator: Wasserman, S.
Partner: UNT Libraries Government Documents Department
open access

Full-scale demonstration of the cintichem process for the production of Mo-99 using a low-enriched target.

Description: The irradiation, disassembly, and processing of two full-scale low-enriched uranium (LEU) targets were recently demonstrated by personnel in the BATAN PUSPIPTEK Facilities (Serpong, Indonesia). Targets were fabricated at Argonne National Laboratory (Argonne, IL, U.S.A.) and shipped to PUSPIPTEK. The processing was done by nearly the same procedure used for the production of {sup 99}Mo from high-enriched uranium (HEU) targets. The BATAN Radioisotope Production Centre produces {sup 99}Mo using th… more
Date: October 28, 1998
Creator: Mutalib, A.
Partner: UNT Libraries Government Documents Department
open access

PDS/PIO: Lightweight Libraries for Collective Parallel I/O

Description: PDS/PIO is a lightweight, parallel interface designed to support efficient transfers of massive, grid-based, simulation data among memory, disk, and tape subsystems. The higher-level PDS (Parallel Data Set) interface manages data with tensor and unstructured grid abstractions, while the lower-level PIO (Parallel Input/Output) interface accesses data arrays with arbitrary permutation, and provides communication and collective 1/0 operations. Higher-level data abstraction for finite element appli… more
Date: October 28, 1998
Creator: Chen, P.; Christon, M.; Heermann, P.D. & Sturtevant, J.
Partner: UNT Libraries Government Documents Department
open access

Progress in developing processes for converting {sup 99}Mo production from high- to low-enriched uranium--1998.

Description: During 1998, the emphasis of our activities was focused mainly on target fabrication. Successful conversion requires a reliable irradiation target; the target being developed uses thin foils of uranium metal, which can be removed from the target hardware for dissolution and processing. This paper describes successes in (1) improving our method for heat-treating the uranium foil to produce a random-small grain structure, (2) improving electrodeposition of zinc and nickel fission-fragment barrier… more
Date: October 28, 1998
Creator: Conner, C.
Partner: UNT Libraries Government Documents Department
open access

Development of a GaAs-Based Monolithic Surface Acoustic Wave Integrated Chemical Microsensor

Description: An oscillator technology using surface acoustic wave delay lines integrated with GaAs MESFET electronics has been developed for GaAs-based integrated microsensor applications. Oscillators with frequencies of 470, 350, and 200 MHz have been designed and fabricated. These oscillators are also promising for other rf applications.
Date: October 28, 1998
Creator: Baca, A. G.; Casalnuovo, S. C.; Drummond, T. J.; Frye, G. C.; Heller, E. J.; Hietala, V. M. et al.
Partner: UNT Libraries Government Documents Department
open access

FTIR and FT-PL Spectroscopic Analysis of TPV Materials and Devices

Description: Impurities in cadmium sulfide (CdS) films are a concern in the fabrication of copper (indium, gallium) diselenide (CIGS) and cadmium telluride (CdTe) photovoltaic devices. Devices incorporating chemical-bath-deposited (CBD) CdS are comparable in quality to devices incorporating purer CdS films grown using vacuum deposition techniques, despite the higher impurity concentrations typically observed in the CBD CdS films. In this paper, we summarize and review the results of Fourier transform infrar… more
Date: October 28, 1998
Creator: Webb, J. D.; Gedvilas, L. M.; Olson, M. R.; Wu, X.; Duda, A.; Wanlass, M. W. et al.
Partner: UNT Libraries Government Documents Department
open access

Assuring safety in the National Ignition Facility

Description: The National Ignition Facility (NIF) is a US Department of Energy inertial confinement laser fusion facility currently under construction at the Lawrence Livermore National Laboratory (LLNL). The NIF mission is to achieve inertial confinement fusion (ICF) ignition, access physical conditions in matter of interest to nuclear weapons effects testing, contribute to the development of inertial fusion for electrical power production, and to support basic science and technology.
Date: April 28, 1998
Creator: Becker, D R; Brereton, S J; Brumburgh, G P; Pryatel, J A; Wolfe, C R & Yatabe, J M
Partner: UNT Libraries Government Documents Department
open access

Behavior of Zircaloy Cladding in the Presence of Gallium

Description: The U.S. Department of Energy has established a dual-track approach to the disposition of plutonium arising from the dismantling of nuclear weapons. Both immobilization and reactor-based mixed-oxide (MOX) fuel technologies are being evaluated. The reactor-based MOX fuel option requires assessment of the potential impact of concentrations of gallium (on the order of 1 to 10 ppm), not present in conventional MOX fuel, on cladding material performance. An experimental program was designed to evalu… more
Date: September 28, 1998
Creator: DiStefano, J. R.; King, J. F.; Manneschmidt, E. T.; Strizak, J. P. & Wilson, D. F.
Partner: UNT Libraries Government Documents Department
open access

Curvature of a cantilever beam subjected to an equi-biaxial bending moment

Description: Results from a finite element analysis of a cantilever beam subjected to an equi-biaxial bending moment demonstrate that the biaxial modulus E/(I-v) must be used even for narrow beams.
Date: April 28, 1998
Creator: Krulevitch, P. & Johnson, G.C.
Partner: UNT Libraries Government Documents Department
open access

Thin film contamination effects on laser-induced damage of fused silica surfaces at 355 nm

Description: Fused silica windows were artificially contaminated to estimate the resistance of target chamber debris shields against laser damage during NIF operation. Uniform contamination thin films (1 to 5 nm thick) were prepared by sputtering various materials (Au, Al, Cu, and B<sub>4</sub>C). The loss of transmission of the samples was first measured. They were then tested at 355 nm in air with an 8-ns Nd:YAG laser. The damage morphologies were characterized by Nomarski optical microscopy and SEM. Both… more
Date: July 28, 1998
Creator: Burnham, A. K.; Cordillot, C.; Fornier, A.; Genin, F. Y.; Rubenchick, A. M.; Schirmann, D. et al.
Partner: UNT Libraries Government Documents Department
open access

Effect of Fluid Flow on Inclusion Coarsening in Low-Alloy Steel Welds

Description: Oxide inclusions form in welds because of deoxidation reactions in the weld pool. These inclusions control the weld microstructure development. Thermodynamic and kinetic calculation of oxidation reaction can describe inclusion characteristics such as number density, size, and composition. Experimental work has shown that fluid-flow velocity gradients in the weld pool can accelerate inclusion growth by collision and coalescence. Moreover, fluid flow in welds can transport inclusions to different… more
Date: February 28, 1998
Creator: Babu, S.S.; David, S.A.; DebRoy, T. & Hong, T.
Partner: UNT Libraries Government Documents Department
open access

Simulations of implosions with a 3D, parallel, unstructured-grid, radiation-hydrodynamics code

Description: An unstructured-grid, radiation-hydrodynamics code is used to simulate implosions. Although most of the problems are spherically symmetric, they are run on 3D, unstructured grids in order to test the code�s ability to maintain spherical symmetry of the converging waves. Three problems, of increasing complexity, are presented. In the first, a cold, spherical, ideal gas bubble is imploded by an enclosing high pressure source. For the second, we add non-linear heat conduction and drive the implosi… more
Date: December 28, 1998
Creator: Kaiser, T. B.; Milovich, J. L.; Prasad, M. K.; Rathkopf, J. & Shestakov, A. I.
Partner: UNT Libraries Government Documents Department
open access

Effect of Americium-241 Content on Plutonium Radiation Source Terms

Description: The management of excess plutonium by the US Department of Energy includes a number of storage and disposition alternatives. Savannah River Site (SRS) is supporting DOE with plutonium disposition efforts, including the immobilization of certain plutonium materials in a borosilicate glass matrix. Surplus plutonium inventories slated for vitrification include materials with elevated levels of Americium-241. The Am-241 content of plutonium materials generally reflects in-growth of the isotope due … more
Date: December 28, 1998
Creator: Rainisch, R.
Partner: UNT Libraries Government Documents Department
open access

Analysis of Hydrogen Depletion Using a Scaled Passive Autocatalytic Recombiner

Description: Hydrogen depletion tests of a scaled passive autocatalytic recombine (pAR) were performed in the Surtsey test vessel at Sandia National Laboratories (SNL). The experiments were used to determine the hydrogen depletion rate of a PAR in the presence of steam and also to evaluate the effect of scale (number of cartridges) on the PAR performance at both low and high hydrogen concentrations.
Date: October 28, 1998
Creator: Blanchat, Thomas K. & Malliakos, Asimios
Partner: UNT Libraries Government Documents Department
open access

A Lattice for the 50 Gev Muon Collider Ring.

Description: A resent progress report on the lattice design of the 50-50 GeV muon collider is presented. The ring circumference needs to be as small as possible due to the short lifetime of the 50 GeV muons. The background at the detector is affected by the continuous decay of muons into electrons which requires a dipole between the high focusing quadrupoles and the detector. To obtain a luminosity on the order of 1 x 10{sup 33} cm{sup {minus}2} S{sup {minus}1} it is required to have beam intensities on the… more
Date: June 28, 1998
Creator: Trbojevic, D.
Partner: UNT Libraries Government Documents Department
open access

Waste minimization in analytical chemistry through innovative sample preparation techniques.

Description: Because toxic solvents and other hazardous materials are commonly used in analytical methods, characterization procedures result in significant and costly amount of waste. We are developing alternative analytical methods in the radiological and organic areas to reduce the volume or form of the hazardous waste produced during sample analysis. For the radiological area, we have examined high-pressure, closed-vessel microwave digestion as a way to minimize waste from sample preparation operations.… more
Date: May 28, 1998
Creator: Smith, L. L.
Partner: UNT Libraries Government Documents Department
open access

Quantum Monte Carlo simulations of disordered magnetic and superconducting materials

Description: Over the last decade, Quantum Monte Carlo (QMC) calculations for tight binding Hamiltonians like the Hubbard and Anderson lattice models have made the transition from addressing abstract issues concerning the effects of electron-electron correlations on magnetic and metal-insulator transitions, to concrete contact with experiment. This paper presents results of applications of �determinant� QMC to systems with disorder such as the conductivity of thin metallic films, the behavior of the magneti… more
Date: January 28, 1998
Creator: Scalettar, R. T.
Partner: UNT Libraries Government Documents Department
open access

Achieving and maintaining cleanliness in NIF amplifiers

Description: Cleanliness measurements made on AMPLAB prototype National Ignition Facility (NIF) laser amplifiers during assembly, cassette transfer, and amplifier operation are summarized. These measurements include particle counts from surface cleanliness assessments using filter swipe techniques and from airborne particle monitoring. Results are compared with similar measurements made on the Beamlet and Nova lasers and in flashlamp test fixtures. Observations of Class 100,000 aerosols after flashlamp firi… more
Date: July 28, 1998
Creator: Burnham, A. K.; Horvath, J. A.; Letts, S. A.; Menapace, J. A. & Stowers, I. F.
Partner: UNT Libraries Government Documents Department
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