Serial/Series Title
Irradiation Processing Department Monthly Report
8
Proceedings of the Workshop on Geothermal Reservoir Engineering
4
Fiscal Year 2001
2
Winter Fuels Report
2
Active Cathodes for Super-High Power Density Solid Oxide Fuel Cells Through Space Charge Effects Quarterly Report
1
CO2 Selective Ceramic Membrane for Water-Gas-Shift Reaction With Concomitant Recovery of CO2, Quarterly Report
1
Cross-Roll Flow Forming of ODS Alloy Heat Exchanger Tubes For Hoop Creep Enhancement Quarterly Report
1
Dense Media Cyclone Optimization Progress Report
1
Development of an Inspection Platform and a Suite of Sensors for Assessing Corrosion and Mechanical Damage on Unpiggable Transmission Mains Quarterly Report
1
Downhole Power Generation and Wireless Communications for Intelligent Completions Applications, Quarterly Report
1
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Activation Measurements for Thermal Neutrons, U.S. Measurements of 36Cl in Mineral Samples from Hiroshima and Nagasaki; and Measurement of 63 Ni in Copper Samples From Hiroshima by Accelerator Mass Spectrometry
The present paper presents the {sup 36}Cl measurement effort in the US. A large number of {sup 36}Cl measurements have been made in both granite and concrete samples obtained from various locations and distances in Hiroshima and Nagasaki. These measurements employed accelerator mass spectrometry (AMS) to quantify the number of atoms of {sup 36}Cl per atom of total Cl in the sample. Results from these measurements are presented here and discussed in the context of the DS02 dosimetry reevaluation effort for Hiroshima and Nagasaki atomic-bomb survivors. The production of {sup 36}Cl by bomb neutrons in mineral samples from Hiroshima and Nagasaki was primarily via the reaction {sup 35}Cl(n,{gamma}){sup 36}Cl. This reaction has a substantial thermal neutron cross-section (43.6 b at 0.025 eV) and the product has a long half-life (301,000 y). hence, it is well suited for neutron-activation detection in Hiroshima and Nagasaki using AMS more than 50 years after the bombings. A less important reaction for bomb neutrons, {sup 39}K(n,{alpha}){sup 36}Cl, typically produces less than 10% of the {sup 36}Cl in mineral samples such as granite and concrete, which contain {approx} 2% potassium. In 1988, only a year after the publication of the DS86 final report (Roesch 1987), it …
Date:
January 14, 2005
Creator:
Straume, Tore; Marchetti, Alfredo A.; Egbert, Stephen D.; Roberts, James A.; Men, Ping; Fujita, Shoichiro et al.
Object Type:
Report
System:
The UNT Digital Library
Active Cathodes for Super-High Power Density Solid Oxide Fuel Cells Through Space Charge Effects Quarterly Report: October 2002 - January 2003
This report summarizes the work done during the first quarter of the project. Effort was directed in three areas: (1) The determination of the role of ionic conductor morphology, used in composite cathodes, on the ionic conductivity of the ionic conductor. It was shown that if the particles are not well sintered, the necks formed between particles will be very narrow, and the resulting conductivity will be too low (resistivity will be too high). Specifically, a mathematical equation was derived to demonstrate the singular nature of conductivity. (2) Nanosize powders of Sc-doped CeO{sub 2} were prepared by combustion synthesis. The rationale is that the particle size of the composite electrode must be as small as possible to ensure a high ionic conductivity--and resulting in high performance in fuel cells. Di-gluconic acid (DGA) was used as fuel. The process led to the formation of nanosize Sc-doped CeO{sub 2}. The powder was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). (3) Samples were sintered to form materials containing various levels of porosity, from {approx}3% to {approx}43%. Conductivity was measured over a range of temperatures by four probe DC method. It was observed that in highly porous samples, the conductivity was …
Date:
April 14, 2003
Creator:
Virkar, Professor Anil V.
Object Type:
Report
System:
The UNT Digital Library
Active Damping of the E-P Instability at the LANL PSR
A prototype of an analog, transverse (vertical) feedback system for active damping of the two-stream (e-p) instability has been developed and successfully tested at the Los Alamos National Laboratory Proton Storage Ring (PSR). This system was able to improve the instability threshold by approximately 30% (as measured by the change in RF buncher voltage at instability threshold). Evidence obtained from these tests suggests that further improvement in performance is limited by beam leakage into the gap at lower RF buncher voltage and the onset of instability in the horizontal plane, which had no feedback. Here we describe the present system configuration, system optimization, results of several recent experimental tests, and results from studies of factors limiting its performance.
Date:
November 14, 2007
Creator:
McCrady, R.; Macek, R.J.; Zaugg, T.; Alamos, /Los; Assadi, S.; Deibele, C. et al.
Object Type:
Article
System:
The UNT Digital Library
Activity of irradiated regular metal in buckets
The potential of shipping a bucket of metal that has not had sufficient decay time is a common problem to all Reactor Processing Operations. The only method at present to assure shipping adequately decayed metal is by procedural control. This study was performed to determine the feasibility of establishing decay time for irradiated metal in buckets by radiation activity measurements.
Date:
September 14, 1964
Creator:
Smith, R. H.
Object Type:
Report
System:
The UNT Digital Library
Adaptation of recent thermal model calculations to x-ray spectra of three old supernova remnants
None
Date:
October 14, 1974
Creator:
Burginyon, G. A.; Hill, R. W. & Seward, F. D.
Object Type:
Article
System:
The UNT Digital Library
Adaptive 4-8 Texture Hierarchies
None
Date:
April 14, 2004
Creator:
Hwa, L M; Duchaineau, M A & Joy, K I
Object Type:
Report
System:
The UNT Digital Library
Adaptive Preconditioning Strategies for Integrating Large KineticMechanisms
None
Date:
March 14, 2013
Creator:
McNenly, M J; Whitesides, R. A. & Flowers, D. L.
Object Type:
Article
System:
The UNT Digital Library
An adaptive radiation model for the origin of new gene functions
None
Date:
June 14, 2005
Creator:
Francino, M. Pilar
Object Type:
Report
System:
The UNT Digital Library
Addendum 6 to CSAR 79-038 out-of-hood plutonium storage (burial box)
The Addendum considered an increase in the limit of fissile material in a stacked container array to 500 grams. In other words, the sum of fissile material in an array of containers is limited to 500 grams, regardless of whether the containers are stacked or not. The results of this evaluation indicates that with the modification of the fissile limits described, the system of a container array will stay sub-critical.
Date:
June 14, 1995
Creator:
Chiao, T.
Object Type:
Report
System:
The UNT Digital Library
Addendum to the 200 West Area Dust Mitigation Strategies: Treatment of the Dust Source Area
This document describes the source area for the blowing dust encountered in the southwest portion of the 200 West Area. Strategies for short-term stabilization of the entire source area, short-term stabilization of a portion of the source area based on levels of respirable dust, and long-term stabilization of the entire source area are provided. An separate evaluation of aerosolized water as a means of reducing airborne dust is also provided.
Date:
May 14, 2001
Creator:
Becker, James M. & Sackschewsky, Michael R.
Object Type:
Report
System:
The UNT Digital Library
Addition of trim coils to the Tandem Mirror Experiment Upgrade (TMX-U) magnet system to improve the magnetic field mapping
The mapping of the magnetic flux bundle from the center cell to the Plasma Potential Control plates (PPC) on the end fan of the Tandem Mirror Experiment Upgrade (TMX-U), was improved by the addition of trim coils (12,000 amp-turns) on each side of each end fan next to the pump beam magnetic shields. The coils' axes are oriented perpendicular to the machine centerline. These coils made the necessary corrections to the field-line mapping, while keeping the field in the nearby pump beam magnetic shield below the saturation threshold. This paper briefly describes the problem, discusses the design as it evolved, and presents the results of the field testing. The disturbance to the field mapping and the appropriate corrections were determined using the code GFUN (a three dimensional electromagnetic field analysis code that includes the presence of permeable materials). The racetrack-shaped coils have dimensions of 1.5 feet by 3 feet and are powered by a renovated 600 kW Bart-Messing power supply controlled by the machine's magnet control system. The magnets were fabricated from polyimide-coated magnet wire. They are rated to 200/sup 0/C, although in pulsed operation they rise only a few degrees centigrade. The coils are placed outside of the vacuum …
Date:
November 14, 1985
Creator:
Wong, R. L.; Pedrotti, L. R.; Baldwin, D. E.; Hibbs, S. M.; Hill, D. N.; Hornady, R. H. et al.
Object Type:
Article
System:
The UNT Digital Library
Addition of Tropospheric Chemistry and Aerosols to the NCAR Community Climate System Model
Atmospheric chemistry and aerosols have several important roles in climate change. They affect the Earth's radiative balance directly: cooling the earth by scattering sunlight (aerosols) and warming the Earth by trapping the Earth's thermal radiation (methane, ozone, nitrous oxide, and CFCs are greenhouse gases). Atmospheric chemistry and aerosols also impact many other parts of the climate system: modifying cloud properties (aerosols can be cloud condensation nuclei), fertilizing the biosphere (nitrogen species and soil dust), and damaging the biosphere (acid rain and ozone damage). In order to understand and quantify the effects of atmospheric chemistry and aerosols on the climate and the biosphere in the future, it is necessary to incorporate atmospheric chemistry and aerosols into state-of-the-art climate system models. We have taken several important strides down that path. Working with the latest NCAR Community Climate System Model (CCSM), we have incorporated a state-of-the-art atmospheric chemistry model to simulate tropospheric ozone. Ozone is not just a greenhouse gas, it damages biological systems including lungs, tires, and crops. Ozone chemistry is also central to the oxidizing power of the atmosphere, which destroys a lot of pollutants in the atmosphere (which is a good thing). We have also implemented a fast chemical mechanism …
Date:
November 14, 2005
Creator:
Cameron-Smith, P.; Lamarque, J.; Connell, P.; Chuang, C.; Rotman, D. & Taylor, J.
Object Type:
Report
System:
The UNT Digital Library
Additional information for impact response of the restart safety rods
WSRC-RP-91-677 studied the structural response of the safety rods under the conditions of brake failure and accidental release. It was concluded that the maximum impact loading to the safety rod is 6020 pounds based on conservative considerations that energy dissipation attributable to fluid resistance and reactor superstructure flexibility. The staffers of the Defense Nuclear Facility Safety Board reviewed the results and inquired about the extent of conservatism. By request of the RESTART team, I reassessed the impact force due to these conservative assumptions. This memorandum reports these assessments.
Date:
October 14, 1991
Creator:
Yau, W. W. F.
Object Type:
Report
System:
The UNT Digital Library
Additional information for impact response of the restart safety rods
WSRC-RP-91-677 studied the structural response of the safety rods under the conditions of brake failure and accidental release. It was concluded that the maximum impact loading to the safety rod is 6020 pounds based on conservative considerations that energy dissipation attributable to fluid resistance and reactor superstructure flexibility. The staffers of the Defense Nuclear Facility Safety Board reviewed the results and inquired about the extent of conservatism. By request of the RESTART team, I reassessed the impact force due to these conservative assumptions. This memorandum reports these assessments.
Date:
October 14, 1991
Creator:
Yau, W. W. F.
Object Type:
Report
System:
The UNT Digital Library
Additional Interface Corner Toughness Data for an Adhesively-Bonded Butt Joint
Over a period of 15 months, five sets of adhesively-bonded butt joints were fabricated and tested. This previously unreported data is used to assess the variability of measured interface corner toughness values, K{sub ac}, as well as the dependence of K{sub ac} on surface preparation. A correlation between K{sub ac} and the size of the adhesive failure zone is also noted.
Date:
April 14, 1999
Creator:
Guess, T.R. & Reedy, E.D.
Object Type:
Article
System:
The UNT Digital Library
Adjustment of the (235)U Fission Spectrum
The latest nuclear data are used to examine the sensitivity of the least squares adjustment of the {sup 235}U fission spectrum to the measured reaction rates, dosimetry cross sections, and prior spectrum covariance matrix. All of these parameters were found to be very important in the spectrum adjustment. The most significant deficiency in the nuclear data is the absence of a good prior covariance matrix. Covariance matrices generated from analytic models of the fission spectra have been used in the past. This analysis reveals some unusual features in the covariance matrix produced with this approach. Specific needs are identified for improved nuclear data to better determine the {sup 235}U spectrum. An improved {sup 235}U covariance matrix and adjusted spectrum are recommended for use in radiation transport sensitivity analyses.
Date:
September 14, 1999
Creator:
GRIFFIN,PATRICK J. & WILLIAMS,J.G.
Object Type:
Article
System:
The UNT Digital Library
Adopting Biophysics Methods in Pursuit of Biogeophysical Research: Advancing the measurement and modeling of electrical signatures of microbe-mineral transformations impacting contaminant transport
This exploratory project involved laboratory experiments to investigate three hypotheses: (H1) Physics-based modeling of low-frequency dispersions (henceforth referred to as alpha) measured in broadband dielectric spectroscopy (DS) data can quantify pore-scale geometric changes impacting contaminant transport resulting from biomineralization; (H2) Physics-based modeling of high-frequency dispersions (henceforth referred to as beta) measured in broadband dielectric spectroscopy data can quantify rates of mineral growth in/on the cell wall; (H3) Application of this measurement and modeling approach can enhance geophysical interpretation of bioremediation experiments conducted at the RIFLE IFC by providing constraints on bioremediation efficiency (biomass concentration, mineral uptake within the cell wall, biomineralization rate). We tested H1 by performing DS measurements (alpha and beta range) on iron (Fe) particles of dimensions similar to microbial cells, dispersed within agar gels over a range of Fe concentrations. We have tested the ability of the physics-based modeling to predict volume concentrations of the Fe particles by assuming that the Fe particles are polarizable inclusions within an otherwise nonpolarizable medium. We evaluated the smallest volume concentration that can be detected with the DS method. Similar experiments and modeling have been performed on the sulfate-reducing bacteria D. vulgaris. Synchrotron x-ray absorption measurements were conducted to determine the …
Date:
June 14, 2013
Creator:
Prodan, Camelia
Object Type:
Report
System:
The UNT Digital Library
Advanced Aerodynamic Devices to Improve the Performance, Economics, Handling, and Safety of Heavy Vehicles
Research is being conducted at the Georgia Tech Research Institute (GTRI) to develop advanced aerodynamic devices to improve the performance, economics, stability, handling and safety of operation of Heavy Vehicles by using previously-developed and flight-tested pneumatic (blown) aircraft technology. Recent wind-tunnel investigations of a generic Heavy Vehicle model with blowing slots on both the leading and trailing edges of the trailer have been conducted under contract to the DOE Office of Heavy Vehicle Technologies. These experimental results show overall aerodynamic drag reductions on the Pneumatic Heavy Vehicle of 50% using only 1 psig blowing pressure in the plenums, and over 80% drag reductions if additional blowing air were available. Additionally, an increase in drag force for braking was confirmed by blowing different slots. Lift coefficient was increased for rolling resistance reduction by blowing only the top slot, while downforce was produced for traction increase by blowing only the bottom. Also, side force and yawing moment were generated on either side of the vehicle, and directional stability was restored by blowing the appropriate side slot. These experimental results and the predicted full-scale payoffs are presented in this paper, as is a discussion of additional applications to conventional commercial autos, buses, motor …
Date:
May 14, 2001
Creator:
Englar, Robert J.
Object Type:
Article
System:
The UNT Digital Library
Advanced diffusion studies with isotopically controlled materials
The use of enriched stable isotopes combined with modern epitaxial deposition and depth profiling techniques enables the preparation of material heterostructures, highly appropriate for self- and foreign-atom diffusion experiments. Over the past decade we have performed diffusion studies with isotopically enriched elemental and compound semiconductors. In the present paper we highlight our recent results and demonstrate that the use of isotopically enriched materials ushered in a new era in the study of diffusion in solids which yields greater insight into the properties of native defects and their roles in diffusion. Our approach of studying atomic diffusion is not limited to semiconductors and can be applied also to other material systems. Current areas of our research concern the diffusion in the silicon-germanium alloys and glassy materials such as silicon dioxide and ion conducting silicate glasses.
Date:
November 14, 2004
Creator:
Bracht, Hartmut A.; Silvestri, Hughes H. & Haller, Eugene E.
Object Type:
Article
System:
The UNT Digital Library
Advanced Electric Traction System Technology Development
As a subcontractor to General Motors (GM), Ames Laboratory provided the technical expertise and supplied experimental materials needed to assess the technology of high energy bonded permanent magnets that are injection or compression molded for use in the Advanced Electric Traction System motor. This support was a sustained (Phase 1: 6/07 to 3/08) engineering effort that builds on the research achievements of the primary FreedomCAR project at Ames Laboratory on development of high temperature magnet alloy particulate in both flake and spherical powder forms. Ames Lab also provide guidance and direction in selection of magnet materials and supported the fabrication of experimental magnet materials for development of injection molding and magnetization processes by Arnold Magnetics, another project partner. The work with Arnold Magnetics involved a close collaboration on particulate material design and processing to achieve enhanced particulate properties and magnetic performance in the resulting bonded magnets. The overall project direction was provided by GM Program Management and two design reviews were held at GM-ATC in Torrance, CA. Ames Lab utilized current expertise in magnet powder alloy design and processing, along with on-going research advances being achieved under the existing FreedomCAR Program project to help guide and direct work during Phase …
Date:
January 14, 2011
Creator:
Anderson, Iver
Object Type:
Report
System:
The UNT Digital Library
Advanced fusion diagnostics. Final technical report, July 15, 1991--July 14, 1993
Key among various issues of ignited plasmas is understanding the physics of energy transfer between thermal plasma particles and magnetically confined, highly energetic charged ions in a tokamak device. The superthermal particles are products of fusion reactions. The efficiency of energy transfer by collisions, from charged fusion products (e.g., {alpha}-particles) to plasma ions, grossly determines whether or not plasma conditions are self-sustaining without recourse to auxiliary heating. Furthermore, should energy transfer (efficiency be poor, and substantial auxiliary heating power is required to maintain reacting conditions within the plasma, economics may preclude commercial viability of fusion reactors. The required charged fusion product information is contained in the energy distribution function of these particles. Knowledge of temporal variations of the superthermal particle energy distribution function could be used by a fusion reactor control system to balance plasma conditions between thermal runaway and a modicum of fusion product energy transfer. Therefore, diagnostics providing data on the dynamical transfer of alpha-particle and other charged fusion product energy to the plasma ions are essential elements for a fusion reactor control system to insure that proper plasma conditions are maintained. The objective of this work is to assess if spectral analysis of rf radiation emitted by …
Date:
July 14, 1993
Creator:
Moses, K. G.
Object Type:
Report
System:
The UNT Digital Library
Advanced Gas Cooled Nuclear Reactor Materials Evaluation and Development Program. Progress report, April 1, 1980-June 30, 1980
Objectives of this program are to evaluate candidate alloys for Very High Temperature Reactor (VHTR) Nuclear Process Heat (NPH) and Direct Cycle Helium Turbine (DCHT) applications, in terms of the effect of simulated reactor primary coolant (helium containing small amounts of various other gases), high temperatures, and long time exposures, on the mechanical properties and structural and surface stability of selected candidate alloys. A second objective is to select and recommend materials for future test facilities and more extensive qualification programs. Work covered in this report includes the activities associated with the status of the simulated reactor helium supply system, testing equipment and gas chemistry analysis instrumentation and equipment. The progress in the screening test program is described; this includes: screening creep results and metallographic analysis for materials thermally exposed or tested at 750, 850 and 950/sup 0/C. The initiation of air creep-rupture testing in the intensive screening test program is discussed. In addition, the status of the data management system is described.
Date:
November 14, 1980
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Advanced gas cooled nuclear reactor materials evaluation and development program. Progress report, July 1, 1977--September 30, 1977
Work covered includes an updated listing of the alloys selected for the screening tests, plus complete test specimen matrices for the screening program. The present design and construction status of the simulated reactor helium loops and testing and analysis facilities and equipment are discussed. Also covered are the loading matrices for the screening creep tests.
Date:
November 14, 1977
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Advanced High Resolution Seismic Imaging, Material Properties Estimation and Full Wavefield Inversion for the Shallow Subsurface
Develop and test advanced near vertical to wide-angle seismic methods for structural imaging and material properties estimation of the shallow subsurface for environmental characterization efforts.
Date:
June 14, 2001
Creator:
Levander, A.; Zelt, C. A. & Symes, W. W.
Object Type:
Report
System:
The UNT Digital Library