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Application of Subspace Detectors to 2012 Sumatera Earthquake Sequence (open access)

Application of Subspace Detectors to 2012 Sumatera Earthquake Sequence

None
Date: September 13, 2013
Creator: Dodge, D
Object Type: Report
System: The UNT Digital Library
Development of Alternative Technetium Waste Forms (open access)

Development of Alternative Technetium Waste Forms

The UREX+1 process is under consideration for the separation of transuranic elements from spent nuclear fuel. The first steps of this process extract the fission product technicium-99 ({sup 99}Tc) into an organic phase containing tributylphosphate together with uranium. Treatment of this stream requires the separation of Tc from U and placement into a suitable waste storage form. A potential candidate waste form involves immobilizing the Tc as an alloy with either excess metallic zirconium or stainless steel. Although Tc-Zr alloys seem to be promising waste forms, alternative materials must be investigated. Innovative studies related to the synthesis and behavior of a different class of Tc materials will increase the scientific knowledge related to development of Tc waste forms. These studies will also provide a better understanding of the behavior of {sup 99}Tc in repository conditions. A literature survey has selected promising alternative waste forms for further study: technetium metallic alloys, nitrides, oxides, sulfides, and pertechnetate salts. The goals of this project are to 1) synthesize and structurally characterize relevant technetium materials that may be considered as waste forms, 2) investigate material behavior in solution under different conditions of temperature, electrochemical potential, and radiation, and 3) predict the long-term behavior of …
Date: September 13, 2013
Creator: Czerwinski, Kenneth
Object Type: Report
System: The UNT Digital Library
EFFECTS OF GAMMA IRRADIATION ON EPDM ELASTOMERS (REVISION 1) (open access)

EFFECTS OF GAMMA IRRADIATION ON EPDM ELASTOMERS (REVISION 1)

Two formulations of EPDM elastomer, one substituting a UV stabilizer for the normal antioxidant in this polymer, and the other the normal formulation, were synthesized and samples of each were exposed to gamma irradiation in initially pure deuterium gas to compare their radiation stability. Stainless steel containers having rupture disks were designed for this task. After 130 MRad dose of cobalt-60 radiation in the SRNL Gamma Irradiation Facility, a significant amount of gas was created by radiolysis; however the composition indicated by mass spectroscopy indicated an unexpected increase in the total amount deuterium in both formulations. The irradiated samples retained their ductility in a bend test. No change of sample weight, dimensions, or density was observed. No change of the glass transition temperature as measured by dynamic mechanical analysis was observed, and most of the other dynamic mechanical properties remained unchanged. There appeared to be an increase in the storage modulus of the irradiated samples containing the UV stabilizer above the glass transition, which may indicate hardening of the material by radiation damage. Revision 1 adds a comparison with results of a study of tritium exposed EPDM. The amount of gas produced by the gamma irradiation was found to be …
Date: September 13, 2013
Creator: Clark, E.
Object Type: Report
System: The UNT Digital Library
Experimental Development and Demonstration of Ultrasonic Measurement Diagnostics for Sodium Fast Reactor Thermal-hydraulics (open access)

Experimental Development and Demonstration of Ultrasonic Measurement Diagnostics for Sodium Fast Reactor Thermal-hydraulics

This research project will address some of the principal technology issues related to sodium-cooled fast reactors (SFR), primarily the development and demonstration of ultrasonic measurement diagnostics linked to effective thermal convective sensing under normatl and off-normal conditions. Sodium is well-suited as a heat transfer medium for the SFR. However, because it is chemically reactive and optically opaque, it presents engineering accessibility constraints relative to operations and maintenance (O&M) and in-service inspection (ISI) technologies that are currently used for light water reactors. Thus, there are limited sensing options for conducting thermohydraulic measurements under normal conditions and off-normal events (maintenance, unanticipated events). Acoustic methods, primarily ultrasonics, are a key measurement technology with applications in non-destructive testing, component imaging, thermometry, and velocimetry. THis project would have yielded a better quantitative and qualitative understanding of the thermohydraulic condition of solium under varied flow conditions. THe scope of work will evaluate and demonstrate ultrasonic technologies and define instrumentation options for the SFR.
Date: September 13, 2013
Creator: Tokuhiro, Akira & Jones, Byron
Object Type: Report
System: The UNT Digital Library
Quantification of UV-Visible and Laser Spectroscopic Techniques for Materials Accountability and Process Control (open access)

Quantification of UV-Visible and Laser Spectroscopic Techniques for Materials Accountability and Process Control

Ultraviolet–visible spectroscopy (UV–Visible) and time-resolved laser fluorescence spectroscopy (TRLFS) optical techniques can permit on-line analysis of actinide elements in a solvent extraction process in real time. These techniques have been used for measuring actinide speciation and concentration under laboratory conditions and are easily adaptable to multiple sampling geometries, such as dip probes, fiber-optic sample cells, and flow-through cell geometries. To fully exploit these techniques, researchers must determine the fundamental speciation of target actinides and the resulting influence on spectroscopic properties. Detection limits, process conditions, and speciation of key actinide components can be established and utilized in a range of areas, particularly those related to materials accountability and process control. Through this project, researchers will develop tools and spectroscopic techniques to evaluate solution extraction conditions and concentrations of U, Pu, and Cm in extraction processes, addressing areas of process control and materials accountability. The team will evaluate UV– Visible and TRLFS for use in solvent extraction-based separations. Ongoing research is examining efficacy of UV-Visible spectroscopy to evaluate uranium and plutonium speciation under conditions found in the UREX process and using TRLFS to evaluate Cm speciation and concentration in the TALSPEAK process. A uranyl and plutonium nitrate UV–Visible spectroscopy study met with …
Date: September 13, 2013
Creator: Czerwinski, Kenneth
Object Type: Report
System: The UNT Digital Library
RESULTS OF ANALYSIS OF NGS CONCENTRATE DRUM SAMPLES [Next Generation Solvent] (open access)

RESULTS OF ANALYSIS OF NGS CONCENTRATE DRUM SAMPLES [Next Generation Solvent]

Savannah River National Laboratory (SRNL) prepared two drums (50 gallons each in �Drum#2� and �Drum#4�) of NGS-MCU (Next Generation Solvent-Modular CSSX Unit) concentrate for future use at MCU in downblending the BOBCalixC6 based solvent to produce NGS-MCU solvent. Samples of each drum were sent for analysis. The results of all the analyses indicate that the blend concentrate is of the correct composition and should produce a blended solvent at MCU of the desired formulation.
Date: September 13, 2013
Creator: Peters, T. & Williams, M.
Object Type: Report
System: The UNT Digital Library
A study of fluid-structure interaction on overlapping grids with a focus on flexible beams (open access)

A study of fluid-structure interaction on overlapping grids with a focus on flexible beams

None
Date: September 13, 2013
Creator: Main, G A
Object Type: Report
System: The UNT Digital Library
Compact X-ray Free Electron Laser from a Laser-plasma Accelerator using a Transverse Gradient Undulator (open access)

Compact X-ray Free Electron Laser from a Laser-plasma Accelerator using a Transverse Gradient Undulator

Compact laser-plasma accelerators can produce high energy electron beams with low emittance, high peak current but a rather large energy spread. The large energy spread hinders the potential applications for coherent FEL radiation generation. In this paper, we discuss a method to compensate the effects of beam energy spread by introducing a transverse field variation into the FEL undulator. Such a transverse gradient undulator together with a properly dispersed beam can greatly reduce the effects of electron energy spread and jitter on FEL performance. We present theoretical analysis and numerical simulations for SASE and seeded extreme ultraviolet and soft x-ray FELs based on laser plasma accelerators.
Date: September 13, 2012
Creator: Huang, Zhirong; Ding, Yuantao; /SLAC; Schroeder, Carl B. & /LBL, Berkeley
Object Type: Article
System: The UNT Digital Library
Final Report for project titled "New fluoroionomer electrolytes with high conductivity and low SO2 crossover for use in electrolyzers being developed for hydrogen production from nuclear power plants" (open access)

Final Report for project titled "New fluoroionomer electrolytes with high conductivity and low SO2 crossover for use in electrolyzers being developed for hydrogen production from nuclear power plants"

Thermochemical water splitting cycles, using the heat of nuclear power plants, offer an alternate highly efficient route for the production of hydrogen. Among the many possible thermochemical cycles for the hydrogen production, the sulfur-based cycles lead the competition in overall energy efficiency. A variant on sulfur-based thermochemical cycles is the Hybrid Sulfur (HyS) Process, which uses a sulfur dioxide depolarized electrolyzer (SDE) to produce hydrogen. The Savannah River National Laboratory (SRNL) selected the fuel cell MEA design concept for the SDE in the HyS process since the MEA concept provides a much smaller cell footprint than conventional parallel plate technology. The electrolyzer oxidizes sulfur dioxide to form sulfuric acid at the anode and reduces protons to form hydrogen at the cathode. The overall electrochemical cell reaction consists of the production of H{sub 2}SO{sub 4} and H{sub 2}. There is a significant need to provide the membrane materials that exhibit reduced sulfur dioxide transport characteristics without sacrificing other important properties such as high ionic conductivity and excellent chemical stability in highly concentrated sulfuric acid solutions saturated with sulfur dioxide. As an alternative membrane, sulfonated Perfluorocyclobutyl aromatic ether polymer (sPFCB) were expected to posses low SO2 permeability due to their stiff backbones …
Date: September 13, 2012
Creator: Smith, Dennis W. & Creager, Stephen
Object Type: Report
System: The UNT Digital Library
Final Technical Progress Report: Nanostructured Magnetic Materials (open access)

Final Technical Progress Report: Nanostructured Magnetic Materials

This report describes progress made during the final phase of our DOE-funded program on Nanostructured Magnetic Materials. This period was quite productive, resulting in the submission of three papers and presentation of three talks at international conferences and three seminars at research institutions. Our DOE-funded research efforts were directed toward studies of magnetism at surfaces and interfaces in high-quality, well-characterized materials prepared by Molecular Beam Epitaxy (MBE) and sputtering. We have an exceptionally well-equipped laboratory for these studies, with: Thin film preparation equipment; Characterization equipment; Equipment to study magnetic properties of surfaces and ultra-thin magnetic films and interfaces in multi-layers and superlattices.
Date: September 13, 2012
Creator: Falco, Charles M.
Object Type: Report
System: The UNT Digital Library
Final Technical Report (open access)

Final Technical Report

BlueFire Ethanol, Inc., a U.S. based corporation with offices in Irvine, California developed a cellulosic biorefinery to convert approximately 700 dry metric tons per day in to 18.9 million gallons per year of cellulosic ethanol. The Project is proposed to be located in the city of Fulton, County of Itawamba, Mississippi.
Date: September 13, 2012
Creator: Cuzens, John & Sumait, Necitas
Object Type: Report
System: The UNT Digital Library
Hydrogen-Helium Mixtures at High Pressure (open access)

Hydrogen-Helium Mixtures at High Pressure

None
Date: September 13, 2012
Creator: Morales, M A; Hamel, S; Caspersen, K & Schwegler, E
Object Type: Article
System: The UNT Digital Library
Investigations on Repository Near-Field Thermal Modeling (open access)

Investigations on Repository Near-Field Thermal Modeling

None
Date: September 13, 2012
Creator: Greenberg, H R; Sharma, M & Sutton, M
Object Type: Report
System: The UNT Digital Library
Novel Low Cost, High Reliability Wind Turbine Drivetrain (open access)

Novel Low Cost, High Reliability Wind Turbine Drivetrain

Clipper Windpower, in collaboration with United Technologies Research Center, the National Renewable Energy Laboratory, and Hamilton Sundstrand Corporation, developed a low-cost, deflection-compliant, reliable, and serviceable chain drive speed increaser. This chain and sprocket drivetrain design offers significant breakthroughs in the areas of cost and serviceability and addresses the key challenges of current geared and direct-drive systems. The use of gearboxes has proven to be challenging; the large torques and bending loads associated with use in large multi-MW wind applications have generally limited demonstrated lifetime to 8-10 years [1]. The large cost of gearbox replacement and the required use of large, expensive cranes can result in gearbox replacement costs on the order of $1M, representing a significant impact to overall cost of energy (COE). Direct-drive machines eliminate the gearbox, thereby targeting increased reliability and reduced life-cycle cost. However, the slow rotational speeds require very large and costly generators, which also typically have an undesirable dependence on expensive rare-earth magnet materials and large structural penalties for precise air gap control. The cost of rare-earth materials has increased 20X in the last 8 years representing a key risk to ever realizing the promised cost of energy reductions from direct-drive generators. A common challenge …
Date: September 13, 2012
Creator: Chobot, Anthony; Das, Debarshi; Mayer, Tyler; Markey, Zach; Martinson, Tim; Reeve, Hayden et al.
Object Type: Report
System: The UNT Digital Library
The Production of Airblast From Solid Rocket Motor Fallbacks (open access)

The Production of Airblast From Solid Rocket Motor Fallbacks

None
Date: September 13, 2012
Creator: Reaugh, J E; Lee, E L & Maienschein, J L
Object Type: Report
System: The UNT Digital Library
Computational Modeling of Uranium and Plutonium Hydriding- the role of Surface Oxide Layers, Oxycarbides, Carbides & Impurities (open access)

Computational Modeling of Uranium and Plutonium Hydriding- the role of Surface Oxide Layers, Oxycarbides, Carbides & Impurities

None
Date: September 13, 2011
Creator: Balasubramanian, K; Siekhaus, W & McLean, W
Object Type: Article
System: The UNT Digital Library
Detection of the Energetic Pulsar PSR B1509-58 And Its Pulsar Wind Nebula in MSH 15-52 Using the Fermi-Large Area Telescope (open access)

Detection of the Energetic Pulsar PSR B1509-58 And Its Pulsar Wind Nebula in MSH 15-52 Using the Fermi-Large Area Telescope

None
Date: September 13, 2011
Creator: Abdo, A. A.; Ackermann, M.; Ajello, M.; Allafort, A.; Asano, K.; Baldini, L. et al.
Object Type: Article
System: The UNT Digital Library
Energy Saving Melting and Revert Reduction Technology (E-SMARRT): Mechanical Performance of Dies (open access)

Energy Saving Melting and Revert Reduction Technology (E-SMARRT): Mechanical Performance of Dies

As a net shape process, die casting is intrinsically efficient and improvements in energy efficiency are strongly dependent on design and process improvements that reduce scrap rates so that more of the total consumed energy goes into acceptable, usable castings. A casting that is distorted and fails to meet specified dimensional requirements is typically remelted but this still results in a decrease in process yield, lost productivity, and increased energy consumption. This work focuses on developing, and expanding the use of, computer modeling methods that can be used to improve the dimensional accuracy of die castings and produce die designs and machine/die setups that reduce rejection rates due to dimensional issues. A major factor contributing to the dimensional inaccuracy of the casting is the elastic deformations of the die cavity caused by the thermo mechanical loads the dies are subjected to during normal operation. Although thermal and die cavity filling simulation are widely used in the industry, structural modeling of the die, particularly for managing part distortion, is not yet widely practiced. This may be due in part to the need to have a thorough understanding of the physical phenomenon involved in die distortion and the mathematical theory employed in …
Date: September 13, 2011
Creator: Miller, R. Allen; Kabiri-Bamoradian, Khalil; Delgado-Garza, Abelardo; Murugesan, Karthik & Ragab, Adham
Object Type: Report
System: The UNT Digital Library
EVALUATION OF ALTERNATIVE FILTER MEDIA FOR THE ROTARY MICROFILTER (open access)

EVALUATION OF ALTERNATIVE FILTER MEDIA FOR THE ROTARY MICROFILTER

SRS is currently developing and testing several processes to treat high level radioactive liquid waste. These processes include the Integrated Salt Disposition Process (ISDP), the Salt Waste Processing Facility (SWPF), and the Small Column Ion Exchange Process (SCIX). Each of these processes has a solid-liquid separation process that limits its throughput. SRNL researchers identified and tested the rotary microfilter as a technology to increase solid-liquid separation throughput. The testing showed significant improvement in filter flux with the rotary microfilter over the baseline crossflow filter (i.e., 2.5-6.5X during scoping tests, as much as 10X in actual waste tests, and approximately 3X in pilot-scale tests). SRNL received funding from DOE EM-21, and subsequently DOE EM-31 to develop the rotary microfilter for high level radioactive service. The work has included upgrading the rotary microfilter for radioactive service, testing with simulated SRS waste streams, and testing it with simulated Hanford waste streams. While the filtration rate is better than that obtained during testing of crossflow filters, the authors believe the rotary microfilter throughput can be improved by using a better filter membrane. The rotary microfilter membrane is made of stainless steel (Pall PMM050). Previous testing, funded by DOE EM-21, showed that asymmetric filters composed …
Date: September 13, 2011
Creator: Poirier, M.; Herman, D. & Bhave, R.
Object Type: Report
System: The UNT Digital Library
Five-Year Summary and Evaluation of Operations and Performance of the Utica Aquifer and North Lake Basin Wetlands Restoration Project in 2004-2009. (open access)

Five-Year Summary and Evaluation of Operations and Performance of the Utica Aquifer and North Lake Basin Wetlands Restoration Project in 2004-2009.

This document reviews the performance of the groundwater (and wetlands) restoration program implemented by the Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA) at the former CCC/USDA grain storage facility in Utica, Nebraska, during the first five years (2004-2009) of this initiative. The report summarizes treatment system operational data and regulatory compliance monitoring results for the site during this period, together with the results of the targeted groundwater sampling and analysis for volatile organic compounds (VOCs) conducted in early 2010 (following completion of the fifth year of systems operation), to assess the initial five years of progress of the Utica remediation effort. On the basis of the 2003 groundwater sampling results, a remedial system employing 4 extraction wells (GWEX1-GWEX4), with groundwater treatment by spray irrigation and conventional air stripping, was implemented with the concurrence of the CCC/USDA and the agencies (Table 1.1). The principal components of the system are shown in Figure 1.3 and are briefly described in Section 1.2. Operation of well GWEX4 and the associated air stripper began on October 29, 2004, and routine operation of wells GWEX1-GWEX3 and the spray irrigation treatment units began on November 22, 2004.
Date: September 13, 2011
Creator: LaFreniere, L. M.
Object Type: Report
System: The UNT Digital Library
Improved resolution of hydrocarbon structures and constitutional isomers in complex mixtures using Gas Chromatography-Vacuum Ultraviolet-Mass Spectrometry (GC-VUV-MS) (open access)

Improved resolution of hydrocarbon structures and constitutional isomers in complex mixtures using Gas Chromatography-Vacuum Ultraviolet-Mass Spectrometry (GC-VUV-MS)

Understanding the composition of complex hydrocarbon mixtures is important for environmental studies in a variety of fields, but many prevalent compounds cannot be confidently identified using traditional gas chromatography-mass spectrometry (GC-MS) techniques. This work uses vacuum-ultraviolet (VUV) ionization to elucidate the structures of a traditionally"unresolved complex mixture" by separating components by GC retention time, tR, and mass-to-charge ratio, m/Q, which are used to determine carbon number, NC, and the number of rings and double bonds, NDBE. Constitutional isomers are resolved based on tR, enabling the most complete quantitative analysis to date of structural isomers in an environmentally-relevant hydrocarbon mixture. Unknown compounds are classified in this work by carbon number, degree of saturation, presence of rings, and degree of branching, providing structural constraints. The capabilities of this analysis are explored using diesel fuel, in which constitutional isomer distribution patterns are shown to be reproducible between carbon numbers and follow predictable rules. Nearly half of the aliphatic hydrocarbon mass is shown to be branched, suggesting branching is more important in diesel fuel than previously shown. The classification of unknown hydrocarbons and the resolution of constitutional isomers significantly improves resolution capabilities for any complex hydrocarbon mixture.
Date: September 13, 2011
Creator: Isaacman, Gabriel; Wilson, Kevin R.; Chan, Arthur W. H.; Worton, David R.; Kimmel, Joel R.; Nah, Theodora et al.
Object Type: Article
System: The UNT Digital Library
Kentucky DOE EPSCoR Program (open access)

Kentucky DOE EPSCoR Program

The KY DOE EPSCoR Program supports two research clusters. The Materials Cluster uses unique equipment and computational methods that involve research expertise at the University of Kentucky and University of Louisville. This team determines the physical, chemical and mechanical properties of nanostructured materials and examines the dominant mechanisms involved in the formation of new self-assembled nanostructures. State-of-the-art parallel computational methods and algorithms are used to overcome current limitations of processing that otherwise are restricted to small system sizes and short times. The team also focuses on developing and applying advanced microtechnology fabrication techniques and the application of microelectrornechanical systems (MEMS) for creating new materials, novel microdevices, and integrated microsensors. The second research cluster concentrates on High Energy and Nuclear Physics. lt connects research and educational activities at the University of Kentucky, Eastern Kentucky University and national DOE research laboratories. Its vision is to establish world-class research status dedicated to experimental and theoretical investigations in strong interaction physics. The research provides a forum, facilities, and support for scientists to interact and collaborate in subatomic physics research. The program enables increased student involvement in fundamental physics research through the establishment of graduate fellowships and collaborative work.
Date: September 13, 2011
Creator: Grulke, Eric & Stencel, John
Object Type: Report
System: The UNT Digital Library
Leptonic B Decays at BaBar (open access)

Leptonic B Decays at BaBar

The authors will present the most recent results on leptonic B decays B{sup {+-}(0)} {yields} K*{sup {+-}(0)} {nu}{bar {nu}} and B{sup {+-}} {yields} {mu}{sup {+-}}{nu}, based on the data collected by the BaBar detector at PEP-II, an asymmetric e{sup +}e{sup -} collider at the center of mass energy of the {Upsilon}(4S) resonance. Rare B decays have always been a standard probe for New Physics (NP) searches. The very low Standard Model (SM) rate of these decays often make them unaccessible with the present experimental datasets, unless NP effects enhance the rate up to the current experimental sensitivity. Moreover, as NP effects can modify the decay kinematic, particular attention must be payed in order to perform a model independent analysis. A B-Factory provides an unique environment where to investigate these processes. The high number of B{bar B} pairs produced by a B-Factory often allows to approach the needed experimental sensitivity. Moreover, the clean environment and the closed kinematic of the initial state enable to obtaining a very pure sample where to look for these decays.
Date: September 13, 2011
Creator: Monorchio, Diego & /INFN, Naples /Naples U.
Object Type: Article
System: The UNT Digital Library
Lightweight and Statistical Techniques for Petascale Debugging: Correctness on Petascale Systems (CoPS) Preliminry Report (open access)

Lightweight and Statistical Techniques for Petascale Debugging: Correctness on Petascale Systems (CoPS) Preliminry Report

Petascale platforms with O(10{sup 5}) and O(10{sup 6}) processing cores are driving advancements in a wide range of scientific disciplines. These large systems create unprecedented application development challenges. Scalable correctness tools are critical to shorten the time-to-solution on these systems. Currently, many DOE application developers use primitive manual debugging based on printf or traditional debuggers such as TotalView or DDT. This paradigm breaks down beyond a few thousand cores, yet bugs often arise above that scale. Programmers must reproduce problems in smaller runs to analyze them with traditional tools, or else perform repeated runs at scale using only primitive techniques. Even when traditional tools run at scale, the approach wastes substantial effort and computation cycles. Continued scientific progress demands new paradigms for debugging large-scale applications. The Correctness on Petascale Systems (CoPS) project is developing a revolutionary debugging scheme that will reduce the debugging problem to a scale that human developers can comprehend. The scheme can provide precise diagnoses of the root causes of failure, including suggestions of the location and the type of errors down to the level of code regions or even a single execution point. Our fundamentally new strategy combines and expands three relatively new complementary debugging approaches. …
Date: September 13, 2011
Creator: de Supinski, B R; Miller, B P & Liblit, B
Object Type: Report
System: The UNT Digital Library