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Medical imaging with coded apertures

Description: Now algorithms were investigated for image reconstruction in emission tomography which could incorporate complex instrumental effects such as might be obtained with a coded aperture system. The investigation focused on possible uses of the wavelet transform to handle non-stationary instrumental effects and analytic continuation of the Radon transform to handle self-absorption. Neither investigation was completed during the funding period and whether such algorithms will be useful remains an ope… more
Date: June 16, 1995
Creator: Keto, E. & Libby, S.
Partner: UNT Libraries Government Documents Department
open access

Single Bunch Stability to Monopole Excitation

Description: We study single bunch stability with respect to monopole longitudinal oscillations in electron storage rings. Our analysis is different from the standard approach based on the linearized Vlasov equation. Rather, we reduce the full nonlinear Fokker-Planck equation to a Schroedinger-like equation which is subsequently analyzed by perturbation theory. We show that the Haissinski solution [3] may become unstable with respect to monopole oscillations and derive a stability criterion in terms of the … more
Date: January 19, 1999
Creator: Podobedov, Boris
Partner: UNT Libraries Government Documents Department
open access

Neutron diffraction study of NiTi during compressive deformation and after shape-memory recovery

Description: Neutron diffraction measurements of internal elastic strains and texture were performed during compressive deformation of martensitic NiTi deforming by twinning. Rietveld refinement of the diffraction spectrum was performed in order to obtain lattice parameter variations and preferred orientation of martensitic variants. The elastic internal strains, are proportional to the externally applied stress but strongly dependent on crystallographic orientation. Plastic deformation by matrix twinning i… more
Date: September 1995
Creator: Dunand, D. C.; Mari, D.; Bourke, Mark A. M. & Goldstone, Joyce A.
Partner: UNT Libraries Government Documents Department
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Maintenance Action Work Plan for Waste Area Grouping 1 inactive tanks 3001-B, 3004-B, T-30, and 3013 at Oak Ridge National Laboratory, Oak Ridge, Tennessee. Environmental Restoration Program

Description: This Maintenance Action Work Plan has been prepared to document the activities and procedures for the remediation of four inactive, low-level radioactive tanks at Waste Area Grouping 1, from the Category D list of tanks in the Federal Facility Agreement for the Oak Ridge Reservation (EPA et al. 1994). The four tanks to remediated are tanks 3001-B, 3004-B, T-30, and 3013. Three of the tanks (3001-B, 3004-B, and T-30) will be physically removed from the ground. Because of logistical issues associ… more
Date: July 1, 1995
Partner: UNT Libraries Government Documents Department
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The LCLS X-Ray FEL at SLAC

Description: The design status and R and D plan of a 1.5 Angstrom SASE-FEL at SLAC, called the Linac Coherent Light Source (LCLS), are described. The LCLS utilizes one third of the SLAC linac for the acceleration of electrons to about 15 GeV. The FEL radiation is produced in a long undulator and is directed to an experimental area for its utilization. The LCLS is designed to produce 300 fsec long radiation pulses at the wavelength of 1.5 Angstrom with 9 GW peak power. This radiation has much higher brightne… more
Date: February 9, 1999
Creator: Cornacchia, Massimo
Partner: UNT Libraries Government Documents Department
open access

Superlattice Photocathodes for Accelerator-Based Polarized Electron Source Applications

Description: A major improvement in the performance of the SLC was achieved with the introduction of thin strained-layer semiconductor crystals. After some optimization, polarizations of 75-85% became standard with lifetimes that were equal to or better than that of thick unstrained crystals. Other accelerators of polarized electrons, generally operating with a much higher duty factor, have now successfully utilized similar photocathodes. For future colliders, the principal remaining problem is the limit on… more
Date: March 22, 1999
Creator: Clendenin, James E
Partner: UNT Libraries Government Documents Department
open access

Results of design calculations. Specification of a prototype zone plate for focusing hard x-rays

Description: A zone plate capable of focusing hard x-rays to less than 1 {mu}m spot size is designed and specified. This design is based on the state-of-art fabrication technology available today. This zone plate consists of Cu/Al layers sputtered alternatively on a round stainless steel core. Parameters of this zone plate are given. The focal length f is given for 8Kev x-rays and the thickness is optimized for focusing efficiency of the same x-ray energy.
Date: January 1991
Creator: Yun, W. B.; Chrzas, J. & Viccaro, P. J.
Partner: UNT Libraries Government Documents Department
open access

Solid Waste Assurance Program Implementation Plan

Description: On June 6, 1995, a waiver to Hanford Site Solid Waste Acceptance Criteria, was approved by the US Department of Energy Richland Operations Office (RL) to replace the low-level, mixed, and transuranic (TRU) generator assessment programs with the Solid Waste Assurance Program (SWAP). This is associated with a waiver that was approved on March 16, 1995 to replace the Storage/Disposal Approval Record (SDAR) requirements with the Waste Specification System (WSS). This implementation plan and the SWA… more
Date: June 19, 1995
Creator: Irons, L.G.
Partner: UNT Libraries Government Documents Department
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Preliminary design and estimate of capital and operating costs for a production scale application of laser decontamination technology

Description: The application of laser ablation technology to the decontamination of radioactive metals, particularly the surfaces of equipment, is discussed. Included is information related to the design, capital and operating costs, and effectiveness of laser ablation technology, based on commercial excimer and Nd:YAG lasers, for the decontamination of production scale equipment.
Date: August 6, 1994
Creator: Pang, Ho-ming & Edelson, M. C.
Partner: UNT Libraries Government Documents Department
open access

Functional design criteria for the self-installing liquid observation well

Description: This document presents the functional design criteria for installing liquid observation wells (LOWs) into single-shell tanks containing ferrocyanide wastes. The LOWs will be designed to accommodate the deployment of gamma, neutron, and electromagnetic induction probes and to interface with the existing tank structure and environment.
Date: June 16, 1995
Creator: Parra, S.A.
Partner: UNT Libraries Government Documents Department
open access

Multidimensional DDT modeling of energetic materials

Description: To model the shock-induced behavior of porous or damaged energetic materials, a nonequilibrium mixture theory has been developed and incorporated into the shock physics code, CTH. The foundation for this multiphase model is based on a continuum mixture formulation given by Baer and Nunziato. This multiphase mixture model provides a thermodynamic and mathematically-consistent description of the self-accelerated combustion processes associated with deflagration-to-detonation and delayed detonatio… more
Date: July 1, 1995
Creator: Baer, M. R.; Hertel, E. S. & Bell, R. L.
Partner: UNT Libraries Government Documents Department
open access

Technical evaluation report for the demonstration of radio frequency soil decontamination at Site S-1

Description: The Air Force`s Armstrong Laboratory at Tyndall Air Force Base, Florida, has supported the research and development of Radio Frequency Soil Decontamination. Radio frequency soil decontamination is essentially a heat-assisted soil vapor extraction process. Site S-1 at Kelly Air Force Base, San Antonio, Texas, was selected for the demonstration of two patented techniques. The site is a former sump that collected spills and surface run-off from a waste petroleum, oils, and lubricants and solvent s… more
Date: April 1, 1995
Creator: Lyon, Chesley R.; Blanchard, Clifton F. & Whitt, Laura H.
Partner: UNT Libraries Government Documents Department
open access

Geomorphology of plutonium in the Northern Rio Grande

Description: Nearly all of the plutonium in the natural environment of the Northern Rio Grande is associated with soils and sediment, and river processes account for most of the mobility of these materials. A composite regional budget for plutonium based on multi-decadal averages for sediment and plutonium movement shows that 90 percent of the plutonium moving into the system is from atmospheric fallout. The remaining 10 percent is from releases at Los Alamos. Annual variation in plutonium flux and storage … more
Date: March 1, 1993
Creator: Graf, William L.
Partner: UNT Libraries Government Documents Department
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Interaction of Slow Electrons With High-Pressure Gases (`Quasi-Liquids`); Synthesis of Our Knowledge on Slow Electron-Molecule Interactions; Final Progress Report, March 15, 1986--August 14, 1987

Description: The rate constant for electron attachment to F{sub 2} was measured at 233 to 373 K in nitrogen at 0.04--0.75 eV and in argon at 298 K at 0.4--2.95 eV. The unfolded cross section was compared with calculations. The ionization threshold of N,N,N{prime},N{prime}-tetramethyl-p-phenylenediamine (TMPD) was measured in ethane over the density range 0.15--13.3 M/l at 295--413 K using multiphoton ionization conductivity.
Date: 1987-23~
Creator: McCorkle, D. L. & Christophorou, L. G.
Partner: UNT Libraries Government Documents Department
open access

Direct Measurement of A{sub c} using Inclusive Charm Tagging at the SLD Detector

Description: We report a new measurement of A{sub c} using data obtained by SLD in 1993-98. This measurement uses a vertex tag technique, where the selection of a c hemisphere is based on the reconstructed mass of the charm hadron decay vertex. The method uses the 3D vertexing capabilities of SLD's CCD vertex detector and the small and stable SLC beams to obtain a high c-event tagging efficiency and purity of 28% and 82%, respectively. Charged kaons identified by the CRID detector and the charge of the reco… more
Date: July 14, 1999
Creator: Abe, K
Partner: UNT Libraries Government Documents Department
open access

Minimum Field Strength in Ultrafast Magnetization Reversal

Description: Ultrafast magnetic field pulses as short as 2 ps are able to reverse the magnetization in thin in-plane magnetized cobalt films. The field pulses are applied in the plane of the film and their direction encompasses all angles with the magnetization. At right angle to the magnetization maximum torque is exerted on the spins. In this geometry a precessional magnetization reversal can be triggered by fields as small as 184 kA/m. Applications in future ultrafast magnetic recording schemes can be fo… more
Date: June 30, 1999
Creator: Garwin, Edward L
Partner: UNT Libraries Government Documents Department
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Stratigraphic variations and secondary porosity within the Maynardville Limestone in Bear Creek Valley, Y-12 Plant, Oak Ridge, Tennessee

Description: To evaluate groundwater and surface water contamination and migration near the Oak Ridge Y-12 plant, a Comprehensive Groundwater Monitoring Plan was developed. As part of the Maynardville exit pathways monitoring program, monitoring well clusters were ii installed perpendicular to the strike of the Maynardville Limestone, that underlies the southern part of the Y-12 Plant and Bear Creek Valley (BCV). The Maynardville Project is designed to locate potential exit pathways of groundwater, study ge… more
Date: May 1, 1995
Creator: Goldstrand, P.M.
Partner: UNT Libraries Government Documents Department
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Chemical decomposition of high-level nuclear waste storage/disposal glasses under irradiation. 1997 annual progress report

Description: 'The objective of this research is to use the sensitive technique of electron spin resonance (ESR) to look for evidence of radiation-induced chemical decomposition of vitreous forms contemplated for immobilization of plutonium and/or high-level nuclear wastes, to interpret this evidence in terms of existing knowledge of glass structure, and to recommend certain materials for further study by other techniques, particularly electron microscopy and measurements of gas evolution by high-vacuum mass… more
Date: January 1, 1997
Creator: Griscom, D.L. & Merzbacher, C.I.
Partner: UNT Libraries Government Documents Department
open access

National low-level waste management program radionuclide report series, Volume 14: Americium-241

Description: This report, Volume 14 of the National Low-Level Waste Management Program Radionuclide Report Series, discusses the radiological and chemical characteristics of americium-241 ({sup 241}Am). This report also includes discussions about waste types and forms in which {sup 241}Am can be found and {sup 241}Am behavior in the environment and in the human body.
Date: September 1, 1995
Creator: Winberg, M. R. & Garcia, R. S.
Partner: UNT Libraries Government Documents Department
open access

Integral Fast Reactor Program annual progress report, FY 1994

Description: This report summarizes highlights of the technical progress made in the Integral Fast Reactor (IFR) Program in FY 1994. Technical accomplishments are presented in the following areas of the IFR technology development activities: metal fuel performance; pyroprocess development; safety experiments and analyses; core design development; fuel cycle demonstration; and LMR technology R&D.
Date: December 1, 1994
Creator: Chang, Y. I.; Walters, L. C.; Laidler, J. J.; Pedersen, D. R.; Wade, D. C. & Lineberry, J. J.
Partner: UNT Libraries Government Documents Department
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Design and construction of deinococcus radiodurans for biodegradation of organic toxins at radioactive DOE waste sites. 1998 annual progress report

Description: 'A 1992 survey of DOE waste sites indicates that about 32% of soils and 45% of groundwaters at these sites contain radionuclides and metals plus an organic toxin class. The most commonly reported combinations of these hazardous compounds being radionuclides and metals (e.g., U, Pu, Cs, Pb, Cr, As) plus chlorinated hydrocarbons (e.g., trichloroethylene), fuel hydrocarbons (e.g., toluene), or polychlorinated biphenyls (e.g., Arochlor 1248). These wastes are some of the most hazardous pollutants a… more
Date: June 1, 1998
Creator: Daly, M. J.; Wackett, L. P. & Minton, K. W.
Partner: UNT Libraries Government Documents Department
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Simultaneous SO{sub 2}/NO{sub x} abatement using zeolite-supported copper. Progress report, October 1, 1993--September 30, 1994

Description: The goals of this project have evolved from an investigation of ways of preparing Li and Hall`s Cu-ZSM-5 catalyst using new methods to yield a more robust catalyst, into an investigation of modified Cu-ZSM-5 catalysts for the simultaneous reduction of NO and oxidation of SO{sub 2}. This was not a conscious effort or decision on the part of the investigators, but resulted from a natural evolution of the project. The authors have developed a zeolite synthesis and characterization capability in th… more
Date: December 31, 1994
Creator: Mitchell, M.B. & White, M.G.
Partner: UNT Libraries Government Documents Department
open access

Nuclear properties for astrophysical applications

Description: We tabulate the ground-state odd-proton and odd-neutron spins, proton and neutron pairing gaps, binding energies, neuton separation energies, quantities related to {beta}-delayed one, two and three neutron emission probabilities, {beta}-decay Q values and half-lives with respect to Gamow-Teller decay, proton separation energies, and {alpha}-decay Q values and half-lives. The starting point of the calculations is a calculation of nuclear ground-states and (information based on the finite-range d… more
Date: September 23, 1994
Creator: Moeller, P.; Nix, J. R. & Kratz, K. L.
Partner: UNT Libraries Government Documents Department
open access

Efficient separations and processing crosscutting program: Develop and test sorbents

Description: This report summarizes work performed during FY 1995 under the task {open_quotes}Develop and Test Sorbents,{close_quotes} the purpose of which is to develop high-capacity, selective solid extractants to recover cesium, strontium, and technetium from nuclear wastes. This work is being done for the Efficient Separations and Processing Crosscutting Program (ESP), operated by the U.S. Department of Energy`s Office of Environmental Management`s Office of Technology Development. The task is under the… more
Date: September 1, 1995
Creator: Bray, L.A.
Partner: UNT Libraries Government Documents Department
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