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QUIET DIRECT SIMULATION OF PLASMAS (open access)

QUIET DIRECT SIMULATION OF PLASMAS

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Date: November 1, 2001
Creator: ALBRIGHT, B. J.; DAUGHTON, W. & AL, ET
Object Type: Article
System: The UNT Digital Library
A High-Performance VME-Based Acquisition System for Positron Emission Mammography (open access)

A High-Performance VME-Based Acquisition System for Positron Emission Mammography

A prototype for a practical and economical breast imaging system for cancer detection is currently under development at Jefferson Lab. The latest advances in bright, fast, crystal scintillators, compact position-sensitive photomultipliers (PSPMT), and high-performance digitizing and readout electronics are being used to develop a compact imager based on Positron Emission Tomography (PET). To facilitate the performance demands of the detector as well as the high number of readout channels, the data acquisition system is built around an intelligent, self-contained, VME form-factor.
Date: November 1, 2001
Creator: Abbott, D.J.; Weisenberger, A.; Majewski, S.; Kieper, D.; Kross, B.; Popov, V. et al.
Object Type: Article
System: The UNT Digital Library
Sulfur Polymer Stabilization/Solidification (Spss) Treatability of Los Alamos National Laboratory Mercury Waste. (open access)

Sulfur Polymer Stabilization/Solidification (Spss) Treatability of Los Alamos National Laboratory Mercury Waste.

Brookhaven National Laboratory's Sulfur Polymer Stabilization/Solidification (SPSS) process was used to treat approximately 90kg of elemental mercury mixed waste from Los Alamos National Laboratory. Treatment was carried out in a series of eight batches using a 1 ft{sup 3} pilot-scale mixer, where mercury loading in each batch was 33.3 weight percent. Although leach performance is currently not regulated for amalgamated elemental mercury (Hg) mixed waste, Toxicity Characteristic Leach Procedure (TCLP) testing of SPSS treated elemental mercury waste indicates that leachability is readily reduced to below the TCLP limit of 200 ppb (regulatory requirement following treatment by retort for wastes containing > 260 ppb Hg), and with process optimization, to levels less than the stringent Universal Treatment Standard (UTS) limit of 25 ppb that is applied to waste containing < 260 ppm Hg. In addition, mercury-contaminated debris, consisting of primary glass and plastic containers, as well as assorted mercury thermometers, switches, and labware, was first reacted with SPSS components to stabilize the mercury contamination, then macroencapsulated in the molten SPSS product. This treatment was done by vigorous agitation of the sulfur polymer powder and the comminuted debris. Larger plastic and metal containers were reacted to stabilize internal mercury contamination, and then …
Date: November 1, 2001
Creator: Adams, J. W. & Kalb, P. D.
Object Type: Report
System: The UNT Digital Library
SO(10) SUSY GUT model with a U(1) x Z2 x Z2 flavor s (open access)

SO(10) SUSY GUT model with a U(1) x Z2 x Z2 flavor s

An SO(10) SUSY GUT model which leads to maximal atmospheric neutrino mixing and the LMA solar neutrino solution, developed in collaboration with S.M. Barr, is briefly described. Since the model is quantitatively predictive, it can be used to assess the need for a neutrino factory, as shown in collaboration with S. Geer.
Date: November 1, 2001
Creator: Albright, Carl H.
Object Type: Article
System: The UNT Digital Library
Versatile Data Acquisition and Controls for EPICS using VME-based FPGAs (open access)

Versatile Data Acquisition and Controls for EPICS using VME-based FPGAs

Field Programmable Gate Arrays (FPGAs) have provided versatile VME based data acquisition and control systems with minimal development times for the Thomas Jefferson National Accelerator Facility (Jefferson Lab). FPGAs have been used to interface with VME controllers using both standard A16 and A24 address modes. VME vector-interrupt capability has also been implemented for timing issues in some applications. FPGA designs have additionally been used to provide controls for various systems by interfacing with Analog to Digital Converters (DAC), interlocks, and other drive signals. These controls can be molded to the individual needs of each system and can provide operators with indicators and controls in EPICS via a VME interface. This allows the developer to choose components and make specifications that are not available commercially. Jefferson Lab has begun developing standard FPGA libraries that result in quick turnaround times and inexpensive designs. There have been approximately eight VME based FPGA designs implanted in one department at Jefferson Lab and they are becoming more widespread. FPGAs continue to become larger and faster enabling systems to be incorporated on one integrated circuit. Inherently, FPGAs can process data faster than many microprocessors due to the small processing overhead associated with a custom FPGA design. …
Date: November 1, 2001
Creator: Allison, Trent & Flood, Roger
Object Type: Article
System: The UNT Digital Library
HYBRIDIZATION AND PRESSURE EFFECTS IN UTX COMPOUNDS (open access)

HYBRIDIZATION AND PRESSURE EFFECTS IN UTX COMPOUNDS

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Date: November 1, 2001
Creator: Alsmadi, A. M.; Sechovsky, V.; Lacerda, A. H.; Prokes, K.; Kamarad, J.; Brück, E. et al.
Object Type: Article
System: The UNT Digital Library
Failure of Stadard Optical Models to Reproduce Neutron Total Cross Section Difference in the W Isotopes (open access)

Failure of Stadard Optical Models to Reproduce Neutron Total Cross Section Difference in the W Isotopes

Recently cross section differences among the isotopes{sup 182,184,186}W have been measured as part of a study of total cross sections in the 5-560 MeV energy range. These measurements show oscillations up to 150 mb between 5 and 100 MeV. Spherical and deformed phenomenological optical potentials with typical radial and isospin dependences show very small oscillations, in disagreement with the data. In a simple Ramsauer model, this discrepancy can be traced to a cancellation between radial and isospin effects. Understanding this problem requires a more detailed model that incorporates a realistic description of the neutron and proton density distributions. This has been done with results of Hartree-Fock-Bogolyubov calculations using the Gogny force, together with a microscopic folding model employing a modification of the JLM potential as an effective interaction. This treatment yields a satisfactory interpretation of the observed total cross section differences.
Date: November 1, 2001
Creator: Anderson, J. D.; Bauer, R. W.; Dietrich, F. S.; Grimes, S. M.; Finlay, R. W.; Abfalterer, W. P. et al.
Object Type: Article
System: The UNT Digital Library
SEPARATION OF CO2 FROM FLUE GASES BY CARBON-MULTIWALL CARBON NANOTUBE MEMBRANES (open access)

SEPARATION OF CO2 FROM FLUE GASES BY CARBON-MULTIWALL CARBON NANOTUBE MEMBRANES

Multiwalled carbon nanotubes (MWNT) were found to be an effective separation media for removing CO{sub 2} from N{sub 2}. The separation mechanism favors the selective condensation of CO{sub 2} from the flowing gas stream. Significant uptakes of CO{sub 2} were measured at 30 C, 150 C and 300 C over the pressure range 0.5 to 5 bar. No measurable uptake of nitrogen was found for this range of conditions. The mass uptake of CO{sub 2} by MWNT was found to increase with increasing temperature. A packed bed of MWNT completely removed CO{sub 2} from a flowing stream of CO{sub 2}/N{sub 2}, and exhibited rapid uptake kinetics for CO{sub 2}.
Date: November 1, 2001
Creator: Andrews, Rodney
Object Type: Report
System: The UNT Digital Library
Handheld Device for Simultaneous Monitoring of Fast Neutrons and Gamma Rays (open access)

Handheld Device for Simultaneous Monitoring of Fast Neutrons and Gamma Rays

Currently at the INEEL, a handheld device is being developed to measure fast neutrons and gamma rays using a single detector instead of a previous two detector system. The handheld detection system presented here uses a single 1/2 inch (diameter) by 1/2 inch (long) liquid scintillator detector (BC501). This means the detection system can be made smaller, lighter, less expensive, and is expected to be more sensitive than the original system. A smaller and lighter device makes it possible to be used in several applications such as customs inspection, border security, environmental radiation monitoring, and so on. The use of only one detector requires that the neutrons and gamma rays be distinguished by the shape of their pulses in the detector. Two methods of pulse shape discrimination (PSD) are: presented here, charge integration and crossover timing. Figures of merit were calculated for both methods for a threshold energy range of 50 to 600 keV. Results show that the crossover method gives much better PSD for electron energy of 100 keV and lower, whereas the charge integration method leads to better separation above 100 keV. However, the neutrons and gamma rays are totally separated for energies of 100 keV and above …
Date: November 1, 2001
Creator: Aryaeinejad, Rahmat; Reber, Edward Lawrence & Spencer, David Frazer
Object Type: Article
System: The UNT Digital Library
Higgs Physics With a Gamma Gamma Collider Based on Clic 1*. (open access)

Higgs Physics With a Gamma Gamma Collider Based on Clic 1*.

We present the machine parameters and physics capabilities of the CLIC Higgs Experiment (CLICHE), a low-energy {gamma}{gamma} collider based on CLIC 1, the demonstration project for the higher-energy two-beam accelerator CLIC. CLICHE is conceived as a factory capable of producing around 20,000 light Higgs bosons per year. We discuss the requirements for the CLIC 1 beams and a laser backscattering system capable of producing a {gamma}{gamma} total (peak) luminosity of 2.0 (0.36) x 10{sup 34} cm{sup -2} s{sup -1} with E{sub CM}({gamma}{gamma}) 115 GeV. We show how CLICHE could be used to measure accurately the mass, {bar b}b, WW and {gamma}{gamma} decays of a light Higgs boson. We illustrate how these measurements may distinguish between the Standard Model Higgs boson and those in supersymmetric and more general two-Higgs-doublet models, complementing the measurements to be made with other accelerators. We also comment on other prospects in {gamma}{gamma} and e{sup -}{gamma} physics with CLICHE.
Date: November 1, 2001
Creator: Asner, D.; Burkhardt, H.; De Roeck, A.; Ellis, J.; Gronberg, J.; Heinemeyer, S. et al.
Object Type: Report
System: The UNT Digital Library
A LOWER BOUND ON THE QUANTUM QUERY COMPLEXITY OF READ-ONCE FUNCTIONS (open access)

A LOWER BOUND ON THE QUANTUM QUERY COMPLEXITY OF READ-ONCE FUNCTIONS

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Date: November 1, 2001
Creator: BARNUM, H. & SAKS, M.
Object Type: Article
System: The UNT Digital Library
Sandia SCADA Program Real-Time Feedback Control of Power Systems (open access)

Sandia SCADA Program Real-Time Feedback Control of Power Systems

This report documents work supporting the Sandia National Laboratories initiative in Distributed Energy Resources (DERs) and Supervisory Control and Data Acquisition (SCADA) systems. One approach for real-time control of power generation assets using feedback control, Quantitative feedback theory (QFT), has recently been applied to voltage, frequency, and phase-control of power systems at Sandia. QFT provided a simple yet powerful philosophy for designing the control systems--allowing the designer to optimize the system by making design tradeoffs without getting lost in complex mathematics. The feedback systems were effective in reducing sensitivity to large and sudden changes in the power grid system. Voltage, frequency, and phase were accurately controlled, even with large disturbances to the power grid system.
Date: November 1, 2001
Creator: BENTLEY, ANTHONY E.; STAMP, JASON E. & CARLSON, ROLF E.
Object Type: Report
System: The UNT Digital Library
LIMITS ON THE EMISSION FROM Fe VIII-XII IN THE HOT LOCAL INTERSTELLAR MEDIUM (open access)

LIMITS ON THE EMISSION FROM Fe VIII-XII IN THE HOT LOCAL INTERSTELLAR MEDIUM

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Date: November 1, 2001
Creator: BLOCH, J. J.; ROUSSEL-DUPRE, D. & AL, ET
Object Type: Article
System: The UNT Digital Library
Cooperative Monitoring Center Occasional Paper/23: The Comprehensive Test Band Treaty: The Way Forward? (open access)

Cooperative Monitoring Center Occasional Paper/23: The Comprehensive Test Band Treaty: The Way Forward?

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Date: November 1, 2001
Creator: BROWN, JAMES & LITTLEFIELD, ADRIANE C.
Object Type: Report
System: The UNT Digital Library
Investigation of Nanoscience Technologies: Final Report (open access)

Investigation of Nanoscience Technologies: Final Report

The intention of this project was to collaborate with Harvard University in the general area of nanoscale structures, biomolecular materials and their application in support of Sandia's MEMS technology. The expertise at Harvard was crucial in fostering these fundamentally interdisciplinary developments. Areas that were of interest included: (1) nanofabrication that exploits traditional methods (from Si technology) and developing new methods; (2) self-assembly of organic and inorganic systems; (3) assembly and dynamics of membranes and microfluidics; (4) study of the hierarchy of scales in assembly; (5) innovative imaging methods; and (6) hard (engineering)/soft (biological) interfaces. Specifically, we decided to work with Harvard to design and construct an experimental test station to measure molecular transport through single nanopores. The pore may be of natural origin, such as a self-assembled bacterial protein in a lipid bilayer, or an artificial structure in silicon or silicon nitride.
Date: November 1, 2001
Creator: BURNS, ALAN R. & MICHALSKE, TERRY A.
Object Type: Report
System: The UNT Digital Library
Functional Materials for Microsystems: Smart Self-Assembled Photochromic Films: Final Report (open access)

Functional Materials for Microsystems: Smart Self-Assembled Photochromic Films: Final Report

This project set out to scientifically-tailor ''smart'' interfacial films and 3-D composite nanostructures to exhibit photochromic responses to specific, highly-localized chemical and/or mechanical stimuli, and to integrate them into optical microsystems. The project involved the design of functionalized chromophoric self-assembled materials that possessed intense and environmentally-sensitive optical properties (absorbance, fluorescence) enabling their use as detectors of specific stimuli and transducers when interfaced with optical probes. The conjugated polymer polydiacetylene (PDA) proved to be the most promising material in many respects, although it had some drawbacks concerning reversibility. Throughout his work we used multi-task scanning probes (AFM, NSOM), offering simultaneous optical and interfacial force capabilities, to actuate and characterize the PDA with localized and specific interactions for detailed characterization of physical mechanisms and parameters. In addition to forming high quality mono-, bi-, and tri-layers of PDA via Langmuir-Blodgett deposition, we were successful in using the diacetylene monomer precursor as a surfactant that directed the self-assembly of an ordered, mesostructured inorganic host matrix. Remarkably, the diacetylene was polymerized in the matrix, thus providing a PDA-silica composite. The inorganic matrix serves as a perm-selective barrier to chemical and biological agents and provides structural support for improved material durability in microsystems. Our original goal …
Date: November 1, 2001
Creator: BURNS, ALAN R.; SASAKI, DARRYL Y.; CARPICK, R.W.; SHELNUTT, JOHN A. & BRINKER, C. JEFFREY
Object Type: Report
System: The UNT Digital Library
Nonlinear evolution in high-density QCD (open access)

Nonlinear evolution in high-density QCD

We consider deeply inelastic scattering at very high energies in the saturation regime. The emerging picture corresponds to the propagation of a dipole, the quark-antiquark pair, in a shock wave color field of the target. We use the formalism of Wilson lines to study the evolution of dipole densities in energy logarithms. Our analysis results into an equation in multicolor limit which sums leading logs but keeps the nonlinearities up to cubic order in densities.
Date: November 1, 2001
Creator: Balitsky, I.I. & Belitsky, A.V.
Object Type: Article
System: The UNT Digital Library
A Novel Integrated Stack Approach for Realizing Mechanically Robust Solid Oxide Fuel Cells (open access)

A Novel Integrated Stack Approach for Realizing Mechanically Robust Solid Oxide Fuel Cells

SOFCs are a very promising energy conversion technology for utilization of fossil fuels. The proposed project is to improve the viability of SOFCs by introducing a novel stacking geometry. The geometry involved has all active SOFC components and the interconnect deposited as thin layers on an electrically insulating support. This allows the choice of a support material that provides optimal mechanical toughness and thermal shock resistance. The supports are in the form of flattened tubes, providing relatively high strength, high packing densities, and minimizing the number of seals required. The integration of SOFCs and interconnects on the same support has several other advantages including the reduction of electrical resistances associated with pressure contacts between the cells and interconnects, relaxation of fabrication tolerances required for pressure contacts, reduction of ohmic losses, and reduction of interconnect conductivity requirements. In this report, we describe the processing methodologies that have been developed for fabricating the integrated solid oxide fuel cell (ISOFC), along with results on characterization of the component materials: support, electrolyte, anode, cathode, and interconnect. Screen printing was the primary processing method developed. A centrifugal casting technique was also developed for depositing thin 8 mol % yttrium stabilized zirconia (YSZ) electrolyte layers on …
Date: November 1, 2001
Creator: Barnett, Scott A.; Lai, Tammy & Liu, Jiang
Object Type: Report
System: The UNT Digital Library
Authentication of Quantum Messages (open access)

Authentication of Quantum Messages

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Date: November 1, 2001
Creator: Barnum, H. & Crepeau, C.
Object Type: Article
System: The UNT Digital Library
THE EFFECT OF BURNUP AND SEPARATION EFFICIENCY ON URANIUM UTILIZATION AND RADIOTOXICITY (open access)

THE EFFECT OF BURNUP AND SEPARATION EFFICIENCY ON URANIUM UTILIZATION AND RADIOTOXICITY

This paper addresses two fundamental issues of fuel cycle sustainability. The two primary issues of interest are efficient use of the natural uranium resource (cradle), and management of nuclear waste radiotoxicity (grave). Both uranium utilization and radiotoxicity are directly influenced by the burnup achieved during irradiation (transmutation related) and where applicable the separation efficiency (partitioning related). Burnup influences the in-growth of transuranics by breeding them into the fuel cycle. Transuranic breeding is virtually essential to resource sustainability because it increases utilization of naturally abundant fertile U-238. However, the direct consequence of this build-up is the in-growth of transuranic isotopes which generally increase the source of future geologically committed radiotoxicity. For scenarios involving recycle, separation efficiency influences the degree to which this transuranic source term is removed from active service in the fuel stream and made a disposal legacy of human activity.
Date: November 1, 2001
Creator: Bays, Samuel & Piet, Steven
Object Type: Article
System: The UNT Digital Library
UNIVERSITY PROGRAMS OF THE U.S. DEPARTMENT OF ENERGY ADVANCED ACCELERATOR APPLICATIONS PROGRAM (open access)

UNIVERSITY PROGRAMS OF THE U.S. DEPARTMENT OF ENERGY ADVANCED ACCELERATOR APPLICATIONS PROGRAM

None
Date: November 1, 2001
Creator: Beller, D. E.; Ward, T. E. & Bresee, J. C.
Object Type: Article
System: The UNT Digital Library
Status and Recent Results for EMSP Project No.70108 Effects of Fluid Distribution on Measured Geophysical Properties for Partially Saturated, Shallow Subsurface Conditions (open access)

Status and Recent Results for EMSP Project No.70108 Effects of Fluid Distribution on Measured Geophysical Properties for Partially Saturated, Shallow Subsurface Conditions

The objective of this report is to improve geophysical imaging of the vadose zone by developing improved methods for interpreting geophysical field data. The purpose of this EMSP project is to develop relationships between laboratory measured geophysical properties and porosity, saturation, soil composition, and fluid distribution, for partially saturated soils. Algorithms for relationships between soil composition, fluids, and geophysical measurements can provide new methods to interpret geophysical field data collected in the vadose zone at sites such as Hanford, WA.
Date: November 1, 2001
Creator: Berge, P. A.; Bonner, B. P.; Roberts, J. J.; Wildenschild, D.; Berryman, J. G. & Bertete-Aquirre, H.
Object Type: Article
System: The UNT Digital Library
ADVANCED DIRECT LIQUEFACTION CONCEPTS FOR PETC GENERIC UNITS (open access)

ADVANCED DIRECT LIQUEFACTION CONCEPTS FOR PETC GENERIC UNITS

The results of Laboratory and Bench-Scale experiments and supporting technical and economic assessments conducted under DOE Contract No. DE-AC22-91PC91040 are reported for the period July 1, 2001 to September 30 2001. This work involves the introduction into the basic two-stage liquefaction process several novel concepts, which include dispersed lower-cost catalysts, coal cleaning by oil agglomeration, and distillate hydrotreating and dewaxing. This project has been modified to include an investigation into the production of value added materials from coal using low-severity liquefaction based technologies.
Date: November 1, 2001
Creator: Berkovich, Adam J.
Object Type: Report
System: The UNT Digital Library
Pine Creek Ranch, FY 2001 Annual Report. (open access)

Pine Creek Ranch, FY 2001 Annual Report.

Pine Creek Ranch was purchased in 1999 by the Confederated Tribes of Warm Springs using Bonneville Power Administration Fish and Wildlife Habitat Mitigation funds. The 25,000 acre property will be managed in perpetuity for the benefit of fish and wildlife habitat. Major issues include: (1) Restoring quality spawning and rearing habitat for stealhead. Streams are incised and fish passage barriers exist from culverts and possibly beaver dams. In addition to stealhead habitat, the Tribes are interested in overall riparian recovery in the John Day River system for wildlife habitat, watershed values and other values such as recreation. (2) Future grazing for specific management purposes. Past grazing practices undoubtedly contributed to current unacceptable conditions. The main stem of Pine Creek has already been enrolled in the CREP program administered by the USDA, Natural Resource Conservation Service in part because of the cost-share for vegetation restoration in a buffer portion of old fields and in part because of rental fees that will help the Tribes to pay the property taxes. Grazing is not allowed in the riparian buffer for the term of the contract. (3) Noxious weeds are a major concern. (4) Encroachment by western juniper throughout the watershed is a potential …
Date: November 1, 2001
Creator: Berry, Mark E.
Object Type: Report
System: The UNT Digital Library