A VUV Photoionization Study of the Combustion-Relevant Reaction of the Phenyl Radical (C6H5) with Propylene (C3H6) in a High Temperature Chemical Reactor (open access)

A VUV Photoionization Study of the Combustion-Relevant Reaction of the Phenyl Radical (C6H5) with Propylene (C3H6) in a High Temperature Chemical Reactor

We studied the reaction of phenyl radicals (C6H5) with propylene (C3H6) exploiting a high temperature chemical reactor under combustion-like conditions (300 Torr, 1,200-1,500 K). The reaction products were probed in a supersonic beam by utilizing tunable vacuum ultraviolet (VUV) radiation from the Advanced Light Source and recording the photoionization efficiency (PIE) curves at mass-to-charge ratios of m/z = 118 (C9H10+) and m/z = 104 (C8H8+). Our results suggest that the methyl and atomic hydrogen losses are the two major reaction pathways with branching ratios of 86 10 percent and 14 10 percent. The isomer distributions were probed by fitting the recorded PIE curves with a linear combination of the PIE curves of the individual C9H10 and C8H8 isomers. Styrene (C6H5C2H3) was found to be the exclusive product contributing to m/z = 104 (C8H8+), whereas 3-phenylpropene, cis-1-phenylpropene, and 2-phenylpropene with branching ratios of 96 4 percent, 3 3 percent, and 1 1 percent could account for signal at m/z = 118 (C9H10+). Although searched for carefully, no evidence of the bicyclic indane molecule could be provided. The reaction mechanisms and branching ratios are explained in terms of electronic structure calculations nicely agreeing with a recent crossed molecular beam study on this …
Date: February 22, 2012
Creator: Manoa, University of Hawaii at; Laboratories, Sandia National; Zhang, Fangtong; Kaiser, Ralf I.; Golan, Amir; Ahmed, Musahid et al.
Object Type: Article
System: The UNT Digital Library
Final Technical Report (open access)

Final Technical Report

The research project focuses on the following topics: a) removal of artifacts in the Doppler spectra from the ARM cloud radars, b) development of the second generation Active Remote Sensing of Cloud Layers (ARSCL) cloud data products, and c) evaluation of ARM cloud property retrievals within the framework of the EarthCARE simulator. We continue to pursue research on areas related to radiative transfer, atmospheric heating rates and related dynamics (topics of interest to the ARM science community at this time) and to contribute on an ad-hoc basis to the science of other ARM-supported principal investigators.
Date: February 22, 2010
Creator: Eugene Clothiaux, Johannes Verlinde, Jerry Harrington
Object Type: Report
System: The UNT Digital Library
Understanding Size Effect in Cleavage Cracking in Thin Materials (open access)

Understanding Size Effect in Cleavage Cracking in Thin Materials

In a specially designed tensile fracture experiment on bicrysal thin films, it was discovered that the fracture toughness of a thin film is not a material constant; rather, as the film becomes thinner it decreases much faster than the prediction of conventional theory. A detailed analysis revealed that this is caused by the mismatch of crystalline structures and, more importantly, with an appropriate crystalline orientation distribution the decrease may be suppressed. This result shed light on the fundamentals of crystal behaviors in pressurized matters. It also provides a promising solution to minimize unexpected failures in nano/micro-electromechanical systems, and therefore is of immense technological importance.
Date: February 22, 2013
Creator: Qiao, Yu
Object Type: Report
System: The UNT Digital Library
Pediatric Clinical Proteomics Center (open access)

Pediatric Clinical Proteomics Center

None
Date: February 22, 2013
Creator: Klein, Jon B
Object Type: Report
System: The UNT Digital Library
Award Nomination Information for Lawrence Livermore National Laboratory SkillSoft Perspectives Conference 2012 (open access)

Award Nomination Information for Lawrence Livermore National Laboratory SkillSoft Perspectives Conference 2012

None
Date: February 22, 2012
Creator: Positeri, L A & Molyneaux, B R
Object Type: Article
System: The UNT Digital Library
Effect of Shim Arm Depletion in the NBSR (open access)

Effect of Shim Arm Depletion in the NBSR

The cadmium shim arms in the NBSR undergo burnup during reactor operation and hence, require periodic replacement. Presently, the shim arms are replaced after every 25 cycles to guarantee they can maintain sufficient shutdown margin. Two prior reports document the expected change in the 113Cd distribution because of the shim arm depletion. One set of calculations was for the present high-enriched uranium fuel and the other for the low-enriched uranium fuel when it was in the COMP7 configuration (7 inch fuel length vs. the present 11 inch length). The depleted 113Cd distributions calculated for these cores were applied to the current design for an equilibrium low-enriched uranium core. This report details the predicted effects, if any, of shim arm depletion on the shim arm worth, the shutdown margin, power distributions and kinetics parameters.
Date: February 22, 2013
Creator: Hanson A. H.; Brown, N. & Diamond, D. J.
Object Type: Report
System: The UNT Digital Library
Entropy-Bayesian Inversion of Time-Lapse Tomographic GPR data for Monitoring Dielectric Permittivity and Soil Moisture Variations (open access)

Entropy-Bayesian Inversion of Time-Lapse Tomographic GPR data for Monitoring Dielectric Permittivity and Soil Moisture Variations

In this study, we evaluate the possibility of monitoring soil moisture variation using tomographic ground penetrating radar travel time data through Bayesian inversion, which is integrated with entropy memory function and pilot point concepts, as well as efficient sampling approaches. It is critical to accurately estimate soil moisture content and variations in vadose zone studies. Many studies have illustrated the promise and value of GPR tomographic data for estimating soil moisture and associated changes, however, challenges still exist in the inversion of GPR tomographic data in a manner that quantifies input and predictive uncertainty, incorporates multiple data types, handles non-uniqueness and nonlinearity, and honors time-lapse tomograms collected in a series. To address these challenges, we develop a minimum relative entropy (MRE)-Bayesian based inverse modeling framework that non-subjectively defines prior probabilities, incorporates information from multiple sources, and quantifies uncertainty. The framework enables us to estimate dielectric permittivity at pilot point locations distributed within the tomogram, as well as the spatial correlation range. In the inversion framework, MRE is first used to derive prior probability density functions (pdfs) of dielectric permittivity based on prior information obtained from a straight-ray GPR inversion. The probability distributions are then sampled using a Quasi-Monte Carlo (QMC) …
Date: February 22, 2013
Creator: Hou, Zhangshuan; Terry, Neil C. & Hubbard, Susan S.
Object Type: Report
System: The UNT Digital Library
Recovery Act: Finite Volume Based Computer Program for Ground Source Heat Pump Systems (open access)

Recovery Act: Finite Volume Based Computer Program for Ground Source Heat Pump Systems

This report is a compilation of the work that has been done on the grant DE-EE0002805 entitled “Finite Volume Based Computer Program for Ground Source Heat Pump Systems.” The goal of this project was to develop a detailed computer simulation tool for GSHP (ground source heat pump) heating and cooling systems. Two such tools were developed as part of this DOE (Department of Energy) grant; the first is a two-dimensional computer program called GEO2D and the second is a three-dimensional computer program called GEO3D. Both of these simulation tools provide an extensive array of results to the user. A unique aspect of both these simulation tools is the complete temperature profile information calculated and presented. Complete temperature profiles throughout the ground, casing, tube wall, and fluid are provided as a function of time. The fluid temperatures from and to the heat pump, as a function of time, are also provided. In addition to temperature information, detailed heat rate information at several locations as a function of time is determined. Heat rates between the heat pump and the building indoor environment, between the working fluid and the heat pump, and between the working fluid and the ground are computed. The heat …
Date: February 22, 2013
Creator: Menart, James A.
Object Type: Report
System: The UNT Digital Library
Cascade Reverse Osmosis Air Conditioning System (open access)

Cascade Reverse Osmosis Air Conditioning System

Advanced Research Projects Agency-Energy project sheet summarizing general information about the Building Energy Efficiency Through Innovative Thermodevices (BEETIT) program including critical needs, innovation and advantages, impacts, and contact information. This sheet discusses air conditioning that has increased electrical efficiency as part of the "Cascade Reverse Osmosis and the Absorption Osmosis Cycle" project.
Date: February 22, 2012
Creator: Batelle Memorial Institute
Object Type: Text
System: The UNT Digital Library
Final Report US Department of Energy DE-FG02-99ER45797 (open access)

Final Report US Department of Energy DE-FG02-99ER45797

This grant focused on atomistic studies of the dynamics of grain boundaries in metals performed largely using molecular dynamics simulations. One of the foci of this period was on the appropriate thermodynamics � in particular the grain boundary stiffness. We worked with a group of researchers at Carnegie Mellon University to make a comparison between grain growth simulations using our grain boundary thermodynamics data and experiments. A separate focus of the supported research looked at shear-driven grain boundary migration. The major focus of our work during this grant was a detailed consideration of the atomic mechanisms associated with grain boundary migration.
Date: February 22, 2013
Creator: Srolovitz, David J. & Haataja, Mikko
Object Type: Report
System: The UNT Digital Library
Components of the dilepton continuum in Pb+Pb collisions at sqrt s = 2.76 TeV (open access)

Components of the dilepton continuum in Pb+Pb collisions at sqrt s = 2.76 TeV

None
Date: February 22, 2012
Creator: Vogt, R; Shukla, P & Kumar, V
Object Type: Article
System: The UNT Digital Library
First Determination of the 8Li Valence Neutron Asymptotic Normalization Coefficient Using the 7Li(8Li,7Li)8Li Reaction (open access)

First Determination of the 8Li Valence Neutron Asymptotic Normalization Coefficient Using the 7Li(8Li,7Li)8Li Reaction

None
Date: February 22, 2013
Creator: Howell, D; Davids, B; Greene, J P; Kanungo, R; Mythili, S; Ruiz, C et al.
Object Type: Article
System: The UNT Digital Library
U.S. Offshore Wind Manufacturing and Supply Chain Development (open access)

U.S. Offshore Wind Manufacturing and Supply Chain Development

The objective of the report is to provide an assessment of the domestic supply chain and manufacturing infrastructure supporting the U.S. offshore wind market. The report provides baseline information and develops a strategy for future development of the supply chain required to support projected offshore wind deployment levels. A brief description of each of the key chapters includes: » Chapter 1: Offshore Wind Plant Costs and Anticipated Technology Advancements. Determines the cost breakdown of offshore wind plants and identifies technical trends and anticipated advancements in offshore wind manufacturing and construction. » Chapter 2: Potential Supply Chain Requirements and Opportunities. Provides an organized, analytical approach to identifying and bounding the uncertainties associated with a future U.S. offshore wind market. It projects potential component-level supply chain needs under three demand scenarios and identifies key supply chain challenges and opportunities facing the future U.S. market as well as current suppliers of the nation’s land-based wind market. » Chapter 3: Strategy for Future Development. Evaluates the gap or competitive advantage of adding manufacturing capacity in the U.S. vs. overseas, and evaluates examples of policies that have been successful . » Chapter 4: Pathways for Market Entry. Identifies technical and business pathways for market entry …
Date: February 22, 2013
Creator: Hamilton, Bruce Duncan
Object Type: Report
System: The UNT Digital Library
Mixer-Ejector Wind Turbine: Breakthrough High Efficiency Shrouded Wind Turbine (open access)

Mixer-Ejector Wind Turbine: Breakthrough High Efficiency Shrouded Wind Turbine

Broad Funding Opportunity Announcement Project: FloDesign Wind Turbine’s innovative wind turbine, inspired by the design of jet engines, could deliver 300% more power than existing wind turbines of the same rotor diameter by extracting more energy over a larger area. FloDesign Wind Turbine’s unique shrouded design expands the wind capture area, and the mixing vortex downstream allows more energy to flow through the rotor without stalling the turbine. The unique rotor and shrouded design also provide significant opportunity for mass production and simplified assembly, enabling mid-scale turbines (approximately 100 kW) to produce power at a cost that is comparable to larger-scale conventional turbines.
Date: February 22, 2010
Creator: unknown
Object Type: Text
System: The UNT Digital Library
Measuring the alpha decay to spontaneous fission branching ratio of 252Cf with the NIFFTE TPC (open access)

Measuring the alpha decay to spontaneous fission branching ratio of 252Cf with the NIFFTE TPC

None
Date: February 22, 2013
Creator: Snyder, L & Greife, U
Object Type: Article
System: The UNT Digital Library
RESULTS FOR THE FOURTH QUARTER 2010 TANK 50 WAC SLURRY SAMPLE: CHEMICAL AND RADIONUCLIDE CONTAMINANT RESULTS (open access)

RESULTS FOR THE FOURTH QUARTER 2010 TANK 50 WAC SLURRY SAMPLE: CHEMICAL AND RADIONUCLIDE CONTAMINANT RESULTS

This report details the chemical and radionuclide contaminant results for the characterization of the 2010 Fourth Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC). Information from this characterization will be used by Liquid Waste Operations (LWO) to support the transfer of low-level aqueous waste from Tank 50 to the Salt Feed Tank in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50 Waste Characterization System. The following conclusions are drawn from the analytical results provided in this report: (1) The concentrations of the reported chemical and radioactive contaminants were less than their respective WAC targets or limits unless noted in this section. (2) The reported detection limits for {sup 94}Nb, {sup 247}Cm and {sup 249}Cf are above the requested limits from Reference 2. However, they are below the limits established in Reference 3. (3) There is an estimated concentration of trimethylbenzene (2.25 mg/L). This is not a WAC analyte, but it is the first time this organic compound has been detected in a quarterly WAC sample from Tank 50. (4) The reported detection limit for Norpar 13 is greater than the limit from Table …
Date: February 22, 2011
Creator: Reigel, M.
Object Type: Report
System: The UNT Digital Library
Spin Transport in Semiconductor heterostructures (open access)

Spin Transport in Semiconductor heterostructures

The focus of the research performed under this grant has been the investigation of spin transport in magnetic semiconductor heterostructures. The interest in these systems is motivated both by their intriguing physical properties, as the physical embodiment of a spin-polarized Fermi liquid, as well as by their potential applications as spintronics devices. In our work we have analyzed several different problems that affect the spin dynamics in single and bi-layer spin-polarized two-dimensional (2D) systems. The topics of interests ranged from the fundamental aspects of the electron-electron interactions, to collective spin and charge density excitations and spin transport in the presence of the spin-orbit coupling. The common denominator of these subjects is the impact at the macroscopic scale of the spin-dependent electron-electron interaction, which plays a much more subtle role than in unpolarized electron systems. Our calculations of several measurable parameters, such as the excitation frequencies of magneto-plasma modes, the spin mass, and the spin transresistivity, propose realistic theoretical estimates of the opposite-spin many-body effects, in particular opposite-spin correlations, that can be directly connected with experimental measurements.
Date: February 22, 2011
Creator: Marinescu, Domnita Catalina
Object Type: Report
System: The UNT Digital Library
High-Performance Buildings – Value, Messaging, Financial and Policy Mechanisms (open access)

High-Performance Buildings – Value, Messaging, Financial and Policy Mechanisms

At the request of the Pacific Northwest National Laboratory, an in-depth analysis of the rapidly evolving state of real estate investments, high-performance building technology, and interest in efficiency was conducted by HaydenTanner, LLC, for the U.S. Department of Energy (DOE) Building Technologies Program. The analysis objectives were • to evaluate the link between high-performance buildings and their market value • to identify core messaging to motivate owners, investors, financiers, and others in the real estate sector to appropriately value and deploy high-performance strategies and technologies across new and existing buildings • to summarize financial mechanisms that facilitate increased investment in these buildings. To meet these objectives, work consisted of a literature review of relevant writings, examination of existing and emergent financial and policy mechanisms, interviews with industry stakeholders, and an evaluation of the value implications through financial modeling. This report documents the analysis methodology and findings, conclusion and recommendations. Its intent is to support and inform the DOE Building Technologies Program on policy and program planning for the financing of high-performance new buildings and building retrofit projects.
Date: February 22, 2011
Creator: McCabe, Molly
Object Type: Report
System: The UNT Digital Library
Facts About XLDB-2011 (open access)

Facts About XLDB-2011

This note provides details of the 5th Extremely Large Databases Conference and Invitational Workshop that were held in 2011 on 18-19 October and 20 October, respectively, at the SLAC National Accelerator Laboratory in Menlo Park, California. The main goals of the conference were: (1) Encourage and accelerate the exchange of ideas between users trying to build extremely large databases worldwide and database solution providers; (2) Share lessons, trends, innovations, and challenges related to building extremely large databases; (3) Facilitate the development and growth of practical technologies for extremely large databases; and (4) Strengthen, expand, and engage the XLDB community.
Date: February 22, 2012
Creator: Becla, Jacek; Lim, Kian-Tat & Wang, Daniel L.
Object Type: Article
System: The UNT Digital Library
End-Of-Life Vehicle Recycling: State of the Art of Resource Recovery From Shredder Residue (open access)

End-Of-Life Vehicle Recycling: State of the Art of Resource Recovery From Shredder Residue

Each year, more than 25 million vehicles reach the end of their service life throughout the world, and this number is rising rapidly because the number of vehicles on the roads is rapidly increasing. In the United States, more than 95% of the 10-15 million scrapped vehicles annually enter a comprehensive recycling infrastructure that includes auto parts recyclers/dismantlers, remanufacturers, and material recyclers (shredders). Today, over 75% of automotive materials, primarily the metals, are profitably recycled via (1) parts reuse and parts and components remanufacturing and (2) ultimately by the scrap processing (shredding) industry. The process by which the scrap processors recover metal scrap from automobiles involves shredding the obsolete automobile hulks, along with other obsolete metal-containing products (such as white goods, industrial scrap, and demolition debris), and recovering the metals from the shredded material. The single largest source of recycled ferrous scrap for the iron and steel industry is obsolete automobiles. The non-metallic fraction that remains after the metals are recovered from the shredded materials - commonly called shredder residue - constitutes about 25% of the weight of the vehicle, and it is disposed of in landfills. This practice is not environmentally friendly, wastes valuable resources, and may become uneconomical. …
Date: February 22, 2011
Creator: Jody, B. J.; Daniels, E. J.; Duranceau, C. M.; Pomykala, J. A. & Spangenberger, J. S. (Energy Systems)
Object Type: Report
System: The UNT Digital Library
Dithering Strategies and Point-Source Photometry (open access)

Dithering Strategies and Point-Source Photometry

The accuracy in the photometry of a point source depends on the point-spread function (PSF), detector pixelization, and observing strategy. The PSF and pixel response describe the spatial blurring of the source, the pixel scale describes the spatial sampling of a single exposure, and the observing strategy determines the set of dithered exposures with pointing offsets from which the source flux is inferred. In a wide-field imaging survey, sources of interest are randomly distributed within the field of view and hence are centered randomly within a pixel. A given hardware configuration and observing strategy therefore have a distribution of photometric uncertainty for sources of fixed flux that fall in the field. In this article we explore the ensemble behavior of photometric and position accuracies for different PSFs, pixel scales, and dithering patterns. We find that the average uncertainty in the flux determination depends slightly on dither strategy, whereas the position determination can be strongly dependent on the dithering. For cases with pixels much larger than the PSF, the uncertainty distributions can be non-Gaussian, with rms values that are particularly sensitive to the dither strategy. We also find that for these configurations with large pixels, pointings dithered by a fractional pixel …
Date: February 22, 2011
Creator: Samsing, Johan & Kim, Alex G
Object Type: Article
System: The UNT Digital Library
Lead-Cooled Fast Reactor (LFR) Design: Safety, Neutronics, Thermal Hydraulics, Structural Mechanics, Fuel, Core, and Plant Design (open access)

Lead-Cooled Fast Reactor (LFR) Design: Safety, Neutronics, Thermal Hydraulics, Structural Mechanics, Fuel, Core, and Plant Design

Fifth chapter from "A Compendium of Reactor Technology" discussing the history and design of lead-cooled fast reactors in nine sections: Lead-cooled Fast Reactor (LFR) Development, Design Criteria and General Specifications, Neutronics, Lead Properties, Compatibility of Structural Materials with Lead, Core, Reactor System, Decay Heat Removal System, and Nuclear Island.
Date: February 22, 2010
Creator: Smith, Craig; Cinotti, L.; Artoli, C. & Grasso, G.
Object Type: Book Chapter
System: The UNT Digital Library
Alternative Energy for Higher Education (open access)

Alternative Energy for Higher Education

This project provides educational opportunities creating both a teaching facility and center for public outreach. The facility is the largest solar array in Nebraska. It was designed to allow students to experience a variety of technologies and provide the public with opportunities for exposure to the implementation of an alternative energy installation designed for an urban setting. The project integrates products from 5 panel manufacturers (including monocrystalline, polycrystalline and thin film technologies) mounted on both fixed and tracking structures. The facility uses both micro and high power inverters. The majority of the system was constructed to serve as an outdoor classroom where panels can be monitored, tested, removed and replaced by students. As an educational facility it primarily serves students in the Creighton University and Metropolitan Community College, but it also provides broader educational opportunities. The project includes a real-time “dashboard” and a historical database of the output of individual inverters and the corresponding meteorological data for researcher and student use. This allows the evaluation of both panel types and the feasibility of installation types in a region of the country subject to significant temperature, wind and precipitation variation.
Date: February 22, 2012
Creator: Michael Cherney, PhD
Object Type: Text
System: The UNT Digital Library
SLUDGE BATCH 7 ACCEPTANCE EVALUATION: RADIONUCLIDE CONCENTRATIONS IN TANK 51 SB7 QUALIFICATION SAMPLE PREPARED AT SRNL (open access)

SLUDGE BATCH 7 ACCEPTANCE EVALUATION: RADIONUCLIDE CONCENTRATIONS IN TANK 51 SB7 QUALIFICATION SAMPLE PREPARED AT SRNL

Presented in this report are radionuclide concentrations required as part of the program of qualifying Sludge Batch Seven (SB7) for processing in the Defense Waste Processing Facility (DWPF). The SB7 material is currently in Tank 51 being washed and prepared for transfer to Tank 40. The acceptance evaluation needs to be completed prior to the transfer of the material in Tank 51 to Tank 40. The sludge slurry in Tank 40 has already been qualified for DWPF and is currently being processed as SB6. The radionuclide concentrations were measured or estimated in the Tank 51 SB7 Qualification Sample prepared at Savannah River National Laboratory (SRNL). This sample was prepared from the three liter qualification sample of Tank 51 sludge slurry (HTF-51-10-125) received on September 18, 2010. The sample was delivered to SRNL where it was initially characterized in the Shielded Cells. With consultation from the Liquid Waste Organization, the qualification sample was then modified by several washes and decants, which included addition of Pu from H Canyon and sodium nitrite per the Tank Farm corrosion control program. This final slurry now has a composition expected to be similar to that of the slurry in Tank 51 after final preparations have …
Date: February 22, 2011
Creator: Pareizs, J. & Hay, M.
Object Type: Report
System: The UNT Digital Library