High-Energy Composite Permanent Magnets (open access)

High-Energy Composite Permanent Magnets

Advanced Research Projects Agency-Energy project sheet summarizing general information about a new program for the development of efficient, high-energy permanent magnets (project title "High-Energy Permanent Magnets for Hybrid Vehicles and Alternative Energy") including critical needs, innovation and advantages, impacts, and contact information. This sheet is the first open solicitation, announcing funding opportunities for involvement in the project.
Date: May 11, 2012
Creator: University of Delaware
Object Type: Text
System: The UNT Digital Library
Mesoscale Benchmark Demonstration Problem 1: Mesoscale Simulations of Intra-granular Fission Gas Bubbles in UO2 under Post-irradiation Thermal Annealing (open access)

Mesoscale Benchmark Demonstration Problem 1: Mesoscale Simulations of Intra-granular Fission Gas Bubbles in UO2 under Post-irradiation Thermal Annealing

A study was conducted to evaluate the capabilities of different numerical methods used to represent microstructure behavior at the mesoscale for irradiated material using an idealized benchmark problem. The purpose of the mesoscale benchmark problem was to provide a common basis to assess several mesoscale methods with the objective of identifying the strengths and areas of improvement in the predictive modeling of microstructure evolution. In this work, mesoscale models (phase-field, Potts, and kinetic Monte Carlo) developed by PNNL, INL, SNL, and ORNL were used to calculate the evolution kinetics of intra-granular fission gas bubbles in UO2 fuel under post-irradiation thermal annealing conditions. The benchmark problem was constructed to include important microstructural evolution mechanisms on the kinetics of intra-granular fission gas bubble behavior such as the atomic diffusion of Xe atoms, U vacancies, and O vacancies, the effect of vacancy capture and emission from defects, and the elastic interaction of non-equilibrium gas bubbles. An idealized set of assumptions was imposed on the benchmark problem to simplify the mechanisms considered. The capability and numerical efficiency of different models are compared against selected experimental and simulation results. These comparisons find that the phase-field methods, by the nature of the free energy formulation, are …
Date: April 11, 2012
Creator: Li, Yulan; Hu, Shenyang Y.; Montgomery, Robert; Gao, Fei; Sun, Xin; Tonks, Michael et al.
Object Type: Report
System: The UNT Digital Library
TECHNETIUM RETENTION IN WTP LAW GLASS WITH RECYCLE FLOW-SHEET DM10 MELTER TESTING VSL-12R2640-1 REV 0 (open access)

TECHNETIUM RETENTION IN WTP LAW GLASS WITH RECYCLE FLOW-SHEET DM10 MELTER TESTING VSL-12R2640-1 REV 0

Melter tests were conducted to determine the retention of technetium and other volatiles in glass while processing simulated Low Activity Waste (LAW) streams through a DM10 melter equipped with a prototypical off-gas system that concentrates and recycles fluid effiuents back to the melter feed. To support these tests, an existing DM10 system installed at Vitreous State Laboratory (VSL) was modified to add the required recycle loop. Based on the Hanford Tank Waste Treatment and Immobilization Plant (WTP) LAW off-gas system design, suitably scaled versions of the Submerged Bed Scrubber (SBS), Wet Electrostatic Precipitator (WESP), and TLP vacuum evaporator were designed, built, and installed into the DM10 system. Process modeling was used to support this design effort and to ensure that issues associated with the short half life of the {sup 99m}Tc radioisotope that was used in this work were properly addressed and that the system would be capable of meeting the test objectives. In particular, this required that the overall time constant for the system was sufficiently short that a reasonable approach to steady state could be achieved before the {sup 99m}Tc activity dropped below the analytical limits of detection. The conceptual design, detailed design, flow sheet development, process model …
Date: December 11, 2012
Creator: Abramowitz, Howard; Brandys, Marek; Cecil, Richard; D' Angelo, Nicholas; Matlack, Keith S. et al.
Object Type: Report
System: The UNT Digital Library
Electron Correlation Effects in Uranium Dioxide from X-ray Emission Spectroscopy (open access)

Electron Correlation Effects in Uranium Dioxide from X-ray Emission Spectroscopy

None
Date: June 11, 2012
Creator: Yu, S W & Tobin, J G
Object Type: Article
System: The UNT Digital Library
Analysis of differences in the ENDL99 and ENDL2009 nuclear data libraries pertaining to 238U (open access)

Analysis of differences in the ENDL99 and ENDL2009 nuclear data libraries pertaining to 238U

None
Date: October 11, 2012
Creator: Ormand, W E; Beck, B; Thompson, I J; Dietrich, F S & Descalle, M A
Object Type: Report
System: The UNT Digital Library
Development and benchmarking of codes for simulation of beam-beam effects at the LHC (open access)

Development and benchmarking of codes for simulation of beam-beam effects at the LHC

N/A
Date: January 11, 2012
Creator: F., Schmidt; Y., Luo & Valishev, A.
Object Type: Report
System: The UNT Digital Library
Comparison of H-Mode Plasmas Diverted to Solid and Liquid Lithium Surfaces (open access)

Comparison of H-Mode Plasmas Diverted to Solid and Liquid Lithium Surfaces

None
Date: June 11, 2012
Creator: et. al, R K
Object Type: Article
System: The UNT Digital Library
Initial Evaluation of Processing Methods for an Epsilon Metal Waste Form (open access)

Initial Evaluation of Processing Methods for an Epsilon Metal Waste Form

During irradiation of nuclear fuel in a reactor, the five metals, Mo, Pd, Rh, Ru, and Tc, migrate to the fuel grain boundaries and form small metal particles of an alloy known as epsilon metal ({var_epsilon}-metal). When the fuel is dissolved in a reprocessing plant, these metal particles remain behind with a residue - the undissolved solids (UDS). Some of these same metals that comprise this alloy that have not formed the alloy are dissolved into the aqueous stream. These metals limit the waste loading for a borosilicate glass that is being developed for the reprocessing wastes. Epsilon metal is being developed as a waste form for the noble metals from a number of waste streams in the aqueous reprocessing of used nuclear fuel (UNF) - (1) the {var_epsilon}-metal from the UDS, (2) soluble Tc (ion-exchanged), and (3) soluble noble metals (TRUEX raffinate). Separate immobilization of these metals has benefits other than allowing an increase in the glass waste loading. These materials are quite resistant to dissolution (corrosion) as evidenced by the fact that they survive the chemically aggressive conditions in the fuel dissolver. Remnants of {var_epsilon}-metal particles have survived in the geologically natural reactors found in Gabon, Africa, indicating …
Date: June 11, 2012
Creator: Crum, Jarrod V.; Strachan, Denis M. & Zumhoff, Mac R.
Object Type: Report
System: The UNT Digital Library
REDUCTION AND SEQUESTRATION OF PERTECHNETATE TO TECHNETIUM DIOXIDE AND PROTECTION FROM RE-OXIDATION (open access)

REDUCTION AND SEQUESTRATION OF PERTECHNETATE TO TECHNETIUM DIOXIDE AND PROTECTION FROM RE-OXIDATION

This effort is part of the technetium management initiative and provides data for the handling and disposition of technetium. To that end, the objective of this effort was to challenge tin(II)apatite (Sn(II)apatite) against double-shell tank 241-AN-I0S simulant spiked with pertechnetate (TcO{sub 4}{sup -}). The Sn(II)apatite used in this effort was synthesized on site using a recipe developed at and provided by Sandia National Laboratories; the synthesis provides a high quality product while requiring minimal laboratory effort. The Sn(II)apatite reduces pertechnetate from the mobile +7 oxidation state to the non-mobile +4 oxidation state. It also sequesters the technetium and does not allow for re-oxidization to the mobile +7 state under acidic or oxygenated conditions within the tested period of time (6 weeks). Previous work indicated that the Sn(II)apatite can achieve an ANSI leachability index in Cast Stone of 12.8. The technetium distribution coefficient for Sn(II)apatite exhibits a direct correlation with the pH of the contaminated media. Table 1 shows Sn(II)apatite distribution coefficients as a function of pH. The asterisked numbers indicate that the lower detection limit of the analytical instrument was used to calculate the distribution coefficient as the concentration of technetium left in solution was less than the detection limit.
Date: July 11, 2012
Creator: JB, DUNCAN; JM, JOHNSON; WP, MOORE; KJ, HAGERTY; RN, RHODES & RC, MOORE
Object Type: Article
System: The UNT Digital Library
The Connection between Galaxies and Dark Matter Structures in the Local Universe (open access)

The Connection between Galaxies and Dark Matter Structures in the Local Universe

We provide new constraints on the connection between galaxies in the local Universe, identified by the Sloan Digital Sky Survey (SDSS), and dark matter halos and their constituent substructures in the {Lambda}CDM model using WMAP7 cosmological parameters. Predictions for the abundance and clustering properties of dark matter halos, and the relationship between dark matter hosts and substructures, are based on a high-resolution cosmological simulation, the Bolshoi simulation. We associate galaxies with dark matter halos and subhalos using subhalo abundance matching, and perform a comprehensive analysis which investigates the underlying assumptions of this technique including (a) which halo property is most closely associated with galaxy stellar masses and luminosities, (b) how much scatter is in this relationship, and (c) how much subhalos can be stripped before their galaxies are destroyed. The models are jointly constrained by new measurements of the projected two-point galaxy clustering and the observed conditional stellar mass function of galaxies in groups. We find that an abundance matching model that associates galaxies with the peak circular velocity of their halos is in good agreement with the data, when scatter of 0.20 {+-} 0.03 dex in stellar mass at a given peak velocity is included. This confirms the theoretical …
Date: July 11, 2012
Creator: Reddick, Rachel M.; Wechsler, Risa H.; Tinker, Jeremy L. & Behroozi, Peter S.
Object Type: Article
System: The UNT Digital Library
Measurement of the Auger Parameter and Wagner Plot for Uranium Compounds (open access)

Measurement of the Auger Parameter and Wagner Plot for Uranium Compounds

None
Date: September 11, 2012
Creator: Holliday, K S; Siekhaus, W & Nelson, A J
Object Type: Article
System: The UNT Digital Library
Ray-tracing tutorial (open access)

Ray-tracing tutorial

N/A
Date: November 11, 2012
Creator: F., Meot
Object Type: Article
System: The UNT Digital Library
Extinction and ecological retreat in a community of primates (open access)

Extinction and ecological retreat in a community of primates

None
Date: May 11, 2012
Creator: Crowley, B. E.; Godfrey, L. R.; Guilderson, T. P.; Zermeno, P.; Koch, P. L. & Dominy, N.
Object Type: Article
System: The UNT Digital Library
Energy from Water and Sunlight (open access)

Energy from Water and Sunlight

Advanced Research Projects Agency-Energy project sheet summarizing general information about a new program to develop an energy storage device that converts water and sunlight into a renewable fuel (project title "Affordable Energy from Water and Sunlight") including critical needs, innovation and advantages, impacts, and contact information. This sheet is the first open solicitation, announcing funding opportunities for involvement in the project.
Date: May 11, 2012
Creator: Sun Catalytix
Object Type: Text
System: The UNT Digital Library
Steam Reforming on Transition-metal Carbides from Density-functional Theory (open access)

Steam Reforming on Transition-metal Carbides from Density-functional Theory

A screening study of the steam reforming reaction on clean and oxygen covered early transition-metal carbides surfaces is performed by means of density-functional theory calculations. It is found that carbides provide a wide spectrum of reactivities, from too reactive via suitable to too inert. Several molybdenum-based systems are identified as possible steam reforming catalysts. The findings suggest that carbides provide a playground for reactivity tuning, comparable to the one for pure metals.
Date: May 11, 2012
Creator: Vojvodic, Aleksandra
Object Type: Article
System: The UNT Digital Library
Energy, Environmental, and Economic Analyses of Design Concepts for the Co-Production of Fuels and Chemicals with Electricity via Co-Gasification of Coal and Biomass (open access)

Energy, Environmental, and Economic Analyses of Design Concepts for the Co-Production of Fuels and Chemicals with Electricity via Co-Gasification of Coal and Biomass

The overall objective of this project was to quantify the energy, environmental, and economic performance of industrial facilities that would coproduce electricity and transportation fuels or chemicals from a mixture of coal and biomass via co-gasification in a single pressurized, oxygen-blown, entrained-flow gasifier, with capture and storage of CO{sub 2} (CCS). The work sought to identify plant designs with promising (Nth plant) economics, superior environmental footprints, and the potential to be deployed at scale as a means for simultaneously achieving enhanced energy security and deep reductions in U.S. GHG emissions in the coming decades. Designs included systems using primarily already-commercialized component technologies, which may have the potential for near-term deployment at scale, as well as systems incorporating some advanced technologies at various stages of R&D. All of the coproduction designs have the common attribute of producing some electricity and also of capturing CO{sub 2} for storage. For each of the co-product pairs detailed process mass and energy simulations (using Aspen Plus software) were developed for a set of alternative process configurations, on the basis of which lifecycle greenhouse gas emissions, Nth plant economic performance, and other characteristics were evaluated for each configuration. In developing each set of process configurations, focused …
Date: March 11, 2012
Creator: Larson, Eric; Williams, Robert; Kreutz, Thomas; Hannula, Ilkka; Lanzini, Andrea & Liu, Guangjian
Object Type: Report
System: The UNT Digital Library
DOE-NNSA Domestic and International Security Training (open access)

DOE-NNSA Domestic and International Security Training

None
Date: October 11, 2012
Creator: O'Brien, M.
Object Type: Article
System: The UNT Digital Library
MacroAlgae Butanol (open access)

MacroAlgae Butanol

Advanced Research Projects Agency-Energy project sheet summarizing general information about a new program formacroalgae aquafaming to increase feedstock and biofuels (project title "MacroAlgae Butanol") including critical needs, innovation and advantages, impacts, and contact information. This sheet is the first open solicitation, announcing funding opportunities for involvement in the project.
Date: May 11, 2012
Creator: E.I. du Pont de Nemours & Company
Object Type: Text
System: The UNT Digital Library
CO2 Capture Using Electric Fields (open access)

CO2 Capture Using Electric Fields

Advanced Research Projects Agency-Energy project sheet summarizing general information about a new program for carbon capture and release (project title "Low-Cost Electrochromic Film on Plastic for Net-Zero Energy Building") including critical needs, innovation and advantages, impacts, and contact information. This sheet is the first open solicitation, announcing funding opportunities for involvement in the project.
Date: May 11, 2012
Creator: Lehigh University
Object Type: Text
System: The UNT Digital Library
Carbon Nanotube Membranes (open access)

Carbon Nanotube Membranes

Advanced Research Projects Agency-Energy project sheet summarizing general information about a new program to use carbon nanotube membranes for removing carbon dioxide from coal plant exhaust (project title "Carbon Nanotube Membranes for Energy-Efficient Carbon Sequestration") including critical needs, innovation and advantages, impacts, and contact information. This sheet is the first open solicitation, announcing funding opportunities for involvement in the project.
Date: May 11, 2012
Creator: Porifera, Inc.
Object Type: Text
System: The UNT Digital Library
General Cause of Sheath Instability Identified for Low Collisionality Plasma in Devices with Secondary Electron Emission (open access)

General Cause of Sheath Instability Identified for Low Collisionality Plasma in Devices with Secondary Electron Emission

A condition for sheath instability due to secondary electron emission (SEE) is derived for low collisionality plasmas. When the SEE coefficient of the electrons bordering the depleted loss cone in energy space exceeds unity, the sheath potential is unstable to a negative perturbation. This result explains three different instability phenomena observed in Hall thruster simulations including a newly found state with spontaneous ~20MHz oscillations. When instabilities occur, the SEE propagating between the walls becomes the dominant contribution to the particle flux, energy loss and axial transport.
Date: May 11, 2012
Creator: M.C. Campanell, A. Khrabrov and I Kaganovich
Object Type: Report
System: The UNT Digital Library
Electroville: Grid-Scale Batteries (open access)

Electroville: Grid-Scale Batteries

Advanced Research Projects Agency-Energy project sheet summarizing general information about a new program for the development of a new large-scale battery technology (project title "Electroville: High Amperage Energy Storage Device - Energy for the Neighborhood" including critical needs, innovation and advantages, impacts, and contact information. This sheet is the first open solicitation, announcing funding opportunities for involvement in the project.
Date: May 11, 2012
Creator: Massachusetts Institute of Technology
Object Type: Text
System: The UNT Digital Library
Cost-Effective Silicon Wafers for Solar Cells (open access)

Cost-Effective Silicon Wafers for Solar Cells

Advanced Research Projects Agency-Energy project sheet summarizing general information about a new program for hydrogen fuel cell vehicles (project title "Direct Wafer Enabling Terawatt Photovoltaics") including critical needs, innovation and advantages, impacts, and contact information. This sheet is the first open solicitation, announcing funding opportunities for involvement in the project.
Date: May 11, 2012
Creator: 1366 Technologies, Inc.
Object Type: Text
System: The UNT Digital Library
Physical Protection at Non-Reactor Facilities (open access)

Physical Protection at Non-Reactor Facilities

None
Date: October 11, 2012
Creator: O'Brien, M
Object Type: Article
System: The UNT Digital Library