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Determination of Basic Structure-Property Relations for Processing and Modeling in Advanced Nuclear Fuel: Microstructure Evolution and Mechanical Properties (open access)

Determination of Basic Structure-Property Relations for Processing and Modeling in Advanced Nuclear Fuel: Microstructure Evolution and Mechanical Properties

The project objective is to study structure-property relations in solid solutions of nitrides and oxides with surrogate elements to simulate the behavior of fuels of inert matrix fuels of interest to the Advanced Fuel Cycle Initiative (AFCI), with emphasis in zirconium-based materials. Work with actual fuels will be carried out in parallel in collaboration with Los Alamos National Laboratory (LANL). Three key aspects will be explored: microstructure characterization through measurement of global texture evolution and local crystallographic variations using Electron Backscattering Diffraction (EBSD); determination of mechanical properties, including fracture toughness, quasi-static compression strength, and hardness, as functions of load and temperature, and, finally, development of structure-property relations to describe mechanical behavior of the fuels based on experimental data. Materials tested will be characterized to identify the mechanisms of deformation and fracture and their relationship to microstructure and its evolution. New aspects of this research are the inclusion of crystallographic information into the evaluation of fuel performance and the incorporation of statistical variations of microstructural variables into simplified models of mechanical behavior of fuels that account explicitly for these variations. The work is expected to provide insight into processing conditions leading to better fuel performance and structural reliability during manufacturing and …
Date: March 1, 2009
Creator: Wheeler, Kirk; Parra, Manuel & Peralta, Pedro
Object Type: Report
System: The UNT Digital Library
REMOVING SLUDGE HEELS FROM SAVANNAH RIVER SITE WASTE TANKS BY OXALIC ACID DISSOLUTION (open access)

REMOVING SLUDGE HEELS FROM SAVANNAH RIVER SITE WASTE TANKS BY OXALIC ACID DISSOLUTION

The Savannah River Site (SRS) will remove sludge as part of waste tank closure operations. Typically the bulk sludge is removed by mixing it with supernate to produce a slurry, and transporting the slurry to a downstream tank for processing. Experience shows that a residual heel may remain in the tank that cannot be removed by this conventional technique. In the past, SRS used oxalic acid solutions to disperse or dissolve the sludge heel to complete the waste removal. To better understand the actual conditions of oxalic acid cleaning of waste from carbon steel tanks, the authors developed and conducted an experimental program to determine its effectiveness in dissolving sludge, the hydrogen generation rate, the generation rate of other gases, the carbon steel corrosion rate, the impact of mixing on chemical cleaning, the impact of temperature, and the types of precipitates formed during the neutralization process. The test samples included actual SRS sludge and simulated SRS sludge. The authors performed the simulated waste tests at 25, 50, and 75 C by adding 8 wt % oxalic acid to the sludge over seven days. They conducted the actual waste tests at 50 and 75 C by adding 8 wt % oxalic …
Date: March 1, 2009
Creator: Poirier, M; David Herman, D; Fernando Fondeur, F; John Pareizs, J; Michael Hay, M; Bruce Wiersma, B et al.
Object Type: Article
System: The UNT Digital Library
DEVELOPMENT OF A CROSSFLOW FILTER TO REMOVE SOLIDS FROM RADIOACTIVE LIQUID WASTE: COMPARISON OF TEST DATA WITH OPERATING EXPERIENCE - 9119 (open access)

DEVELOPMENT OF A CROSSFLOW FILTER TO REMOVE SOLIDS FROM RADIOACTIVE LIQUID WASTE: COMPARISON OF TEST DATA WITH OPERATING EXPERIENCE - 9119

In 2008, the Savannah River Site (SRS) began treatment of liquid radioactive waste from its Tank Farms. To treat waste streams containing {sup 137}Cs, {sup 90}Sr, and actinides, SRS developed the Actinide Removal Process (ARP) and the Modular Caustic Side Solvent Extraction Unit (MCU). The Actinide Removal Process contacts the waste with monosodium titanate (MST) to sorb strontium and select actinides. After MST contact, the process filters the resulting slurry to remove the MST (with sorbed strontium and actinides) and any entrained sludge. The filtrate is transported to the MCU to remove cesium. The solid particle removed by the filter are concentrated to {approx} 5 wt %, washed to reduce the concentration of dissolved sodium, and transported to the Defense Waste Processing Facility (DWPF) for vitrification. The authors conducted tests with 0.5 {micro} and 0.1 {micro} Mott sintered stainless steel crossflow filter at bench-scale (0.19 ft{sup 2} surface area) and pilot-scale (11.2 ft{sup 2}). The collected data supported design of the filter for the process and identified preferred operating conditions for the full-scale process (230 ft{sup 2}). The testing investigated the influence of operating parameters, such as filter pore size, axial velocity, transmembrane pressure, and solids loading, on filter flux, …
Date: March 1, 2009
Creator: Poirier, M; David Herman, D; Samuel Fink, S & Julius Lacerna, J
Object Type: Article
System: The UNT Digital Library
Task 1: Steam Oxidation,” (open access)

Task 1: Steam Oxidation,”

Need to improve efficiency, decrease emissions (esp. CO2) associated with the continued use of coal for power generation
Date: March 1, 2009
Creator: Wright, I. G. & Holcomb, G. R.
Object Type: Article
System: The UNT Digital Library
Modeling of Pressurized Electrochemistry and Steam-Methane Reforming in Solid Oxide Fuel Cells and the Effects on Thermal and Electrical Stack Performance (open access)

Modeling of Pressurized Electrochemistry and Steam-Methane Reforming in Solid Oxide Fuel Cells and the Effects on Thermal and Electrical Stack Performance

Summarizes work done to extend the electrochemical performance and methane reforming submodels to include the effects of pressurization and to demonstrate this new modeling capability by simulating large stacks operating on methane-rich fuel under pressurized and non-pressurized conditions. Pressurized operation boosts electrochemical performance, alters the kinetics of methane reforming, and effects the equilibrium composition of methane fuels. This work developed constitutive submodels that couple the electrochemistry, reforming, and pressurization to yield an increased capability of the modeling tool for prediction of SOFC stack performance.
Date: March 1, 2009
Creator: Recknagle, Kurtis P. & Khaleel, Mohammad A.
Object Type: Report
System: The UNT Digital Library
Summary of Training Workshop on the Use of NASA tools for Coastal Resource Management in the Gulf of Mexico (open access)

Summary of Training Workshop on the Use of NASA tools for Coastal Resource Management in the Gulf of Mexico

A two-day training workshop was held in Xalapa, Mexico from March 10-11 2009 with the goal of training end users from the southern Gulf of Mexico states of Campeche and Veracruz in the use of tools to support coastal resource management decision-making. The workshop was held at the computer laboratory of the Institute de Ecologia, A.C. (INECOL). This report summarizes the results of that workshop and is a deliverable to our NASA client.
Date: March 1, 2009
Creator: Judd, Chaeli; Judd, Kathleen S.; Gulbransen, Thomas C. & Thom, Ronald M.
Object Type: Report
System: The UNT Digital Library
Task 2: Materials for Oxy-Combustion Systems, (open access)

Task 2: Materials for Oxy-Combustion Systems,

Modeling of oxy-combustion environments based on different strategies
Date: March 1, 2009
Creator: Holcomb, G. R.; Shim, H.-S.; Meier, G. & Natesan, K.
Object Type: Article
System: The UNT Digital Library
Wireless Roadside Inspection Proof of Concept Test Final Report (open access)

Wireless Roadside Inspection Proof of Concept Test Final Report

The U.S. Department of Transportation (DOT) FMCSA commissioned the Wireless Roadside Inspection (WRI) Program to validate technologies and methodologies that can improve safety through inspections using wireless technologies that convey real-time identification of commercial vehicles, drivers, and carriers, as well as information about the condition of the vehicles and their drivers. It is hypothesized that these inspections will: -- Increase safety -- Decrease the number of unsafe commercial vehicles on the road; -- Increase efficiency -- Speed up the inspection process, enabling more inspections to occur, at least on par with the number of weight inspections; -- Improve effectiveness -- Reduce the probability of drivers bypassing CMV inspection stations and increase the likelihood that fleets will attempt to meet the safety regulations; and -- Benefit industry -- Reduce fleet costs, provide good return-on-investment, minimize wait times, and level the playing field. The WRI Program is defined in three phases which are: Phase 1: Proof of Concept Test (POC) Testing of commercially available off-the-shelf (COTS) or near-COTS technology to validate the wireless inspection concept. Phase 2: Pilot Test Safety technology maturation and back office system integration Phase 3: Field Operational Test Multi-vehicle testing over a multi-state instrumented corridor This report focuses …
Date: March 1, 2009
Creator: Capps, Gary J; Franzese, Oscar; Knee, Helmut E; Plate, Randall S & Lascurain, Mary Beth
Object Type: Report
System: The UNT Digital Library
Progress Update,” NETL CO2 Capture Technology for Existing Plants (open access)

Progress Update,” NETL CO2 Capture Technology for Existing Plants

Progress Update,” NETL CO2 Capture Technology for Existing Plants
Date: March 1, 2009
Creator: Holcomb, D. Huckaby and G. R.
Object Type: Article
System: The UNT Digital Library

Fireside Corrosion in Oxyfuel Combustion Environments,”

Oxy-fired or low-nitrogen combustion is a technology that will facilitate CO2 capture while also reducing NOx formation and which offers the opportunity for near-zero emissions coal combustion via either the retrofit of existing power plants, or the design of new power plants. Because of the opportunity to improve the environmental performance of the existing coal fired fleet (currently approximately 800 GW of capacity in the US alone) and the potential for converting these plants from air-blown to oxy-fired burners, NETL’s Office of Research & Development is focusing its attention on the impact of retrofitting existing plants on the service life of the materials of construction
Date: March 1, 2009
Creator: Holcomb, G. R.; Matthes, S. A.; Rawers, J. C. & Covino, B. S., Jr.
Object Type: Poster
System: The UNT Digital Library
Summary of the LARP Mini-Workshop on Electron Lens Simulations at BNL (open access)

Summary of the LARP Mini-Workshop on Electron Lens Simulations at BNL

N/A
Date: March 1, 2009
Creator: Valishev, A.; Luo, Y. & Fischer, W.
Object Type: Report
System: The UNT Digital Library
[TSDC Business Meeting] (open access)

[TSDC Business Meeting]

Handwritten notes from Texas Stonewall Democratic Caucus Business Meeting on March 1, 2009.
Date: March 1, 2009
Creator: unknown
Object Type: Text
System: The UNT Digital Library
[Texas Stonewall Democratic Caucus Leadership Award] (open access)

[Texas Stonewall Democratic Caucus Leadership Award]

Texas Stonewall Democratic Caucus Buck Massey Legacy of Leadership Award presented to Jesse Garcia on March 1, 2009.
Date: March 1, 2009
Creator: unknown
Object Type: Text
System: The UNT Digital Library
[Conference Registration Form for Jodie Eldridge] (open access)

[Conference Registration Form for Jodie Eldridge]

Registration form filled out by Jodie Eldridge for the Texas Stonewall Democratic Caucus Statewide Conference in Austin.
Date: March 1, 2009
Creator: unknown
Object Type: Text
System: The UNT Digital Library
[Handwritten note for TSDC] (open access)

[Handwritten note for TSDC]

Handwritten note on March 1, 2009 regarding bringing more allies and using ActBlue.
Date: March 1, 2009
Creator: unknown
Object Type: Text
System: The UNT Digital Library
[Texas Stonewall Democratic Caucus Club Achievement Award] (open access)

[Texas Stonewall Democratic Caucus Club Achievement Award]

Texas Stonewall Democratic Caucus Club Achievement Award presented to Houston Stonewall Young Democrats on March 1, 2009.
Date: March 1, 2009
Creator: unknown
Object Type: Text
System: The UNT Digital Library
[Handwritten note for TSDC] (open access)

[Handwritten note for TSDC]

Handwritten note on March 1, 2009 regarding Linda Allen Webmaster and John-Thomas Musselman Technology Workshop.
Date: March 1, 2009
Creator: unknown
Object Type: Text
System: The UNT Digital Library
[Texas Stonewall Democratic Caucus Advocate Award] (open access)

[Texas Stonewall Democratic Caucus Advocate Award]

Texas Stonewall Democratic Caucus Lone Star Equality Advocate Award presented to Hon. Senfronia Thompson on March 1, 2009.
Date: March 1, 2009
Creator: unknown
Object Type: Text
System: The UNT Digital Library
Preliminary Assessment of ATR-C Capabilities to Provide Integral Benchmark Data for Key Structural/Matrix Materials that May be Used for Nuclear Data Testing and Analytical Methods Validation (open access)

Preliminary Assessment of ATR-C Capabilities to Provide Integral Benchmark Data for Key Structural/Matrix Materials that May be Used for Nuclear Data Testing and Analytical Methods Validation

The purpose of this research is to provide a fundamental computational investigation into the possible integration of experimental activities with the Advanced Test Reactor Critical (ATR-C) facility with the development of benchmark experiments. Criticality benchmarks performed in the ATR-C could provide integral data for key matrix and structural materials used in nuclear systems. Results would then be utilized in the improvement of nuclear data libraries and as a means for analytical methods validation. It is proposed that experiments consisting of well-characterized quantities of materials be placed in the Northwest flux trap position of the ATR-C. The reactivity worth of the material could be determined and computationally analyzed through comprehensive benchmark activities including uncertainty analyses. Experiments were modeled in the available benchmark model of the ATR using MCNP5 with the ENDF/B-VII.0 cross section library. A single bar (9.5 cm long, 0.5 cm wide, and 121.92 cm high) of each material could provide sufficient reactivity difference in the core geometry for computational modeling and analysis. However, to provide increased opportunity for the validation of computational models, additional bars of material placed in the flux trap would increase the effective reactivity up to a limit of 1$ insertion. For simplicity in assembly manufacture, …
Date: March 1, 2009
Creator: Bess, John D.
Object Type: Report
System: The UNT Digital Library
A low-frequency asymptotic model of seismic reflection from a high-permeability layer (open access)

A low-frequency asymptotic model of seismic reflection from a high-permeability layer

Analysis of compression wave propagation through a high-permeability layer in a homogeneous poroelastic medium predicts a peak of reflection in the low-frequency end of the spectrum. An explicit formula expresses the resonant frequency through the elastic moduli of the solid skeleton, the permeability of the reservoir rock, the fluid viscosity and compressibility, and the reservoir thickness. This result is obtained through a low-frequency asymptotic analysis of the Biot's model of poroelasticity. A new physical interpretation of some coefficients of the classical poroelasticity is a result of the derivation of the main equations from the Hooke's law, momentum and mass balance equations, and the Darcy's law. The velocity of wave propagation, the attenuation factor, and the wave number, are expressed in the form of power series with respect to a small dimensionless parameter. The latter is equal to the product of the kinematic reservoir fluid mobility, an imaginary unit, and the frequency of the signal. Retaining only the leading terms of the series leads to explicit and relatively simple expressions for the reflection and transmission coefficients for a planar wave crossing an interface between two permeable media, as well as wave reflection from a thin highly-permeable layer (a lens). The practical …
Date: March 1, 2009
Creator: Silin, Dmitriy & Goloshubin, Gennady
Object Type: Report
System: The UNT Digital Library
Energy and water sector policy strategies for drought mitigation. (open access)

Energy and water sector policy strategies for drought mitigation.

Tensions between the energy and water sectors occur when demand for electric power is high and water supply levels are low. There are several regions of the country, such as the western and southwestern states, where the confluence of energy and water is always strained due to population growth. However, for much of the country, this tension occurs at particular times of year (e.g., summer) or when a region is suffering from drought conditions. This report discusses prior work on the interdependencies between energy and water. It identifies the types of power plants that are most likely to be susceptible to water shortages, the regions of the country where this is most likely to occur, and policy options that can be applied in both the energy and water sectors to address the issue. The policy options are designed to be applied in the near term, applicable to all areas of the country, and to ease the tension between the energy and water sectors by addressing peak power demand or decreased water supply.
Date: March 1, 2009
Creator: Kelic, Andjelka; Vugrin, Eric D.; Loose, Verne W. & Vargas, Vanessa N.
Object Type: Report
System: The UNT Digital Library
A search for muon neutrino and antineutrino disappearance in MiniBooNE (open access)

A search for muon neutrino and antineutrino disappearance in MiniBooNE

The MiniBooNE Collaboration reports a search for {nu}{sub {mu}} and {bar {nu}}{sub {mu}} disappearance in the {Delta}m{sup 2} region of a few eV{sup 2}. These measurements are important for constraining models with extra types of neutrinos, extra dimensions and CPT violation. Fits to the shape of the {nu}{sub {mu}} and {bar {nu}}{sub {mu}} energy spectra reveal no evidence for disappearance at 90% confidence level (CL) in either mode. This is the first test of {bar {nu}}{sub {mu}} disappearance between {Delta}m{sup 2} = 0.1-10 eV{sup 2}.
Date: March 1, 2009
Creator: Aguilar-Arevalo, Alexis A.; Anderson, C. E.; Bazarko, A. O.; Brice, S. J.; Brown, Bruce C.; Bugel, Leonard G. et al.
Object Type: Article
System: The UNT Digital Library
Sandia National Laboratories support of the Iraq Nuclear Facility Dismantlement and Disposal Program. (open access)

Sandia National Laboratories support of the Iraq Nuclear Facility Dismantlement and Disposal Program.

Because of past military operations, lack of upkeep and looting there are now enormous radioactive waste problems in Iraq. These waste problems include destroyed nuclear facilities, uncharacterized radioactive wastes, liquid radioactive waste in underground tanks, wastes related to the production of yellow cake, sealed radioactive sources, activated metals and contaminated metals that must be constantly guarded. Iraq currently lacks the trained personnel, regulatory and physical infrastructure to safely and securely manage these facilities and wastes. In 2005 the International Atomic Energy Agency (IAEA) agreed to organize an international cooperative program to assist Iraq with these issues. Soon after, the Iraq Nuclear Facility Dismantlement and Disposal Program (the NDs Program) was initiated by the U.S. Department of State (DOS) to support the IAEA and assist the Government of Iraq (GOI) in eliminating the threats from poorly controlled radioactive materials. The Iraq NDs Program is providing support for the IAEA plus training, consultation and limited equipment to the GOI. The GOI owns the problems and will be responsible for implementation of the Iraq NDs Program. Sandia National Laboratories (Sandia) is a part of the DOS's team implementing the Iraq NDs Program. This report documents Sandia's support of the Iraq NDs Program, which …
Date: March 1, 2009
Creator: Cochran, John Russell & Danneels, Jeffrey John
Object Type: Report
System: The UNT Digital Library
Wide-Field Astronomical Surveys in the Next Decade (open access)

Wide-Field Astronomical Surveys in the Next Decade

Wide-angle surveys have been an engine for new discoveries throughout the modern history of astronomy, and have been among the most highly cited and scientifically productive observing facilities in recent years. This trend is likely to continue over the next decade, as many of the most important questions in astrophysics are best tackled with massive surveys, often in synergy with each other and in tandem with the more traditional observatories. We argue that these surveys are most productive and have the greatest impact when the data from the surveys are made public in a timely manner. The rise of the 'survey astronomer' is a substantial change in the demographics of our field; one of the most important challenges of the next decade is to find ways to recognize the intellectual contributions of those who work on the infrastructure of surveys (hardware, software, survey planning and operations, and databases/data distribution), and to make career paths to allow them to thrive.
Date: March 1, 2009
Creator: Strauss, Michael A.; Tyson, J.Anthony; Anderson, Scott F.; Axelrod, T. S.; Becker, Andrew C.; Bickerton, Steven J. et al.
Object Type: Report
System: The UNT Digital Library