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Differentiating neutrino models on the basis of $\theta_{13}$ and lepton flavor violation (open access)

Differentiating neutrino models on the basis of $\theta_{13}$ and lepton flavor violation

The authors show how models of neutrino masses and mixings can be differentiated on the basis of their predictions for {theta}{sub 13} and lepton flavor violation in radiative charged lepton decays and {mu} - e conversion. They illustrate the lepton flavor violation results for five predictive SO(10) SUSY GUT models and point out the relative importance of their heavy right-handed neutrino mass spectra and {theta}{sub 13} predictions.
Date: March 1, 2008
Creator: Albright, Carl H.
System: The UNT Digital Library
The U.S. Department of Energy's Aerial Measuring System (AMS) (open access)

The U.S. Department of Energy's Aerial Measuring System (AMS)

For nearly 40 years, aerial radiological search and survey missions have been performed by the United States Department of Energy's (USDOE) Remote Sensing Laboratory (RSL). Originally created in 1967 as Aerial Measurement Operations (AMO), the AMS mission has expanded to include acquiring baseline measurements, performing periodic area monitoring, and responding to radiological emergencies. In an accident scenario, AMS fixed-wing and/or rotary-wing systems can be deployed to map radiological deposition. A fixed-wing system is on standby twenty-fours per day, seven days per week and can be deployed within four hours of notification. It can quickly evaluate high levels of radiation which may constitute immediate health risks. To accomplish its mission the fixed-wing aircraft utilizes the Spectral Aerial Radiological Computer System (SPARCS) which records gross count and spectral information. Data from SPARCS is telemetered to ground stations and secure websites where it can be viewed and evaluated in near-real time. The rotary-wing system deploys following the critical phase of an accident and supports the DOE's Consequence Management Response Team (CMRT) in determining long term consequences of the accident. The rotary wing aircraft utilizes the Radiation and Environmental Data Acquisition and Recording System (REDAR). A 25-liter sodium iodide (NaI) spectral system and precise …
Date: March 1, 2008
Creator: Marianno, Craig
System: The UNT Digital Library
Update on Mechanical Analysis of Monolithic Fuel Plates (open access)

Update on Mechanical Analysis of Monolithic Fuel Plates

Results on the relative bond strength of the fuel-clad interface in monolithic fuel plates have been presented at previous RRFM conferences. An understanding of mechanical properties of the fuel, cladding, and fuel / cladding interface has been identified as an important area of investigation and quantification for qualification of monolithic fuel forms. Significant progress has been made in the area of mechanical analysis of the monolithic fuel plates, including mechanical property determination of fuel foils, cladding processed by both hot isostatic pressing and friction bonding, and the fuel-clad composite. In addition, mechanical analysis of fabrication induced residual stress has been initiated, along with a study to address how such stress can be relieved prior to irradiation. Results of destructive examinations and mechanical tests are presented along with analysis and supporting conclusions. A brief discussion of alternative non-destructive evaluation techniques to quantify not only bond quality, but also bond integrity and strength, will also be provided. These are all necessary steps to link out-of-pile observations as a function of fabrication with in-pile behaviours.
Date: March 1, 2008
Creator: Burkes, D. E.; Rice, F. J.; Jue, J.-F. & Hallinan, N. P.
System: The UNT Digital Library
FRMAC Mission Analysis: What is it, and why is it useful? (open access)

FRMAC Mission Analysis: What is it, and why is it useful?

In 2002, the Director of the U.S. Department of Energy's (DOE's) National Nuclear Security Administration, Division of Emergency Response, requested a team of DOE scientists, considered experts in the field of radiological consequence management, assemble and construct a mission analysis upon which the DOE could build its response program and plan for future requirements. The team developed five scenarios upon which to build the data quality objectives (DQOs) that they considered necessary to ensure a comprehensive consequence management response from the DOE perspective. The resulting document was called the Consequence Management Mission Analysis. Based upon the positive reaction to this document and its obvious benefit to the Consequence Management mission, it was decided to expand the scope of the document to cover a mission analysis of the entire Federal Radiological Monitoring and Assessment Center (FRMAC) mission. The documentation team was expanded to include representatives from all signatories to the National Response Plan who have a role in responding to radiological emergencies. The scope of the FRMAC Mission Analysis includes all federal response resources which are activated to provide rapid support to affected state and local governments in the form of radiological monitoring and dose assessment activities at the incident site. …
Date: March 1, 2008
Creator: Hopkins, Rhonda
System: The UNT Digital Library
Comparative Genome Analysis in the Integrated Microbial Genomes (IMG) System (open access)

Comparative Genome Analysis in the Integrated Microbial Genomes (IMG) System

Comparative genome analysis is critical for the effectiveexploration of a rapidly growing number of complete and draft sequencesfor microbial genomes. The Integrated Microbial Genomes (IMG) system(img.jgi.doe.gov) has been developed as a community resource thatprovides support for comparative analysis of microbial genomes in anintegrated context. IMG allows users to navigate the multidimensionalmicrobial genome data space and focus their analysis on a subset ofgenes, genomes, and functions of interest. IMG provides graphicalviewers, summaries and occurrence profile tools for comparing genes,pathways and functions (terms) across specific genomes. Genes can befurther examined using gene neighborhoods and compared with sequencealignment tools.
Date: March 1, 2006
Creator: Kyrpides, Nikos C. & Markowitz, Victor M.
System: The UNT Digital Library
Measurement of the ratio of the p anti-p ---> W+c-jet cross section to the inclusive p anti-p ---> W+jets cross section (open access)

Measurement of the ratio of the p anti-p ---> W+c-jet cross section to the inclusive p anti-p ---> W+jets cross section

None
Date: March 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
System: The UNT Digital Library
Si Memory Chip as a Sensitive Neutron Detector (open access)

Si Memory Chip as a Sensitive Neutron Detector

A novel neutron detector is based on semiconductor technology. A boron-containing film is an integral part of the semiconductor device and is in physical contact with the charge-storage medium (CSM). The CSM is a proprietary cell design known as MirrorBit{trademark}, which is different from conventional memory designs such as SRAM or DRAM. The design doubles the resolution and sensitivity in the array. This enables a highly effective detection of the secondary particles, {sup 7}Li and {sup 4}He, produced due to neutron capture by {sup 10}B in the device. Other approaches using semiconductor materials for neutron detection have employed single-diode detectors that require off-system preamplifiers to filter and condition the signal. There are several advantages to this non-volatile detector, one being that it requires no power for detection and retains the signal until reset. Further, this detector, a semiconductor chip, can be seamlessly integrated into other systems. Finally, the semiconductor manufacturing process on which the detector is based will allow for a high-volume and low-cost alternative to current detectors. MirrorBit{trademark} chips were exposed to neutron flux and the signals recorded. Detailed results from this experiment will be described in this presentation.
Date: March 1, 2008
Creator: Quam, William
System: The UNT Digital Library
Progress to Develop an Advanced Solar-Selective Coating (open access)

Progress to Develop an Advanced Solar-Selective Coating

The progress to develop a durable advanced solar-selective coating will be described. Experimental work has focused on modeling high-temperature, solar-selective coatings; depositing the individual layers and modeled coatings; measuring the optical, thermal, morphology, and compositional properties and using the data to validate the modeled and deposited properties; re-optimizing the coating; and testing the coating performance and durability.
Date: March 1, 2008
Creator: Kennedy, C. E.
System: The UNT Digital Library
Estimating Filtering Errors Using the Peano Kernel Theorem (open access)

Estimating Filtering Errors Using the Peano Kernel Theorem

The Peano Kernel Theorem is introduced and a frequency domain derivation is given. It is demonstrated that the application of this theorem yields simple and accurate formulas for estimating the error introduced into a signal by filtering it to reduce noise.
Date: March 1, 2008
Creator: Blair, Jerome
System: The UNT Digital Library
Sensitivity of Concentrating Solar Power Trough Performance, Cost and Financing with Solar Advisor Model (open access)

Sensitivity of Concentrating Solar Power Trough Performance, Cost and Financing with Solar Advisor Model

A comprehensive solar technology systems analysis model, the Solar Advisor Model (SAM) was developed to support the federal R&D community and the solar industry. This model, developed by staff at NREL and Sandia National Laboratory, is able to model the costs, finances, and performance of concentrating solar power and photovoltaics (PV). Currently, parabolic troughs and concentrating PV are the two concentrating technologies modeled within the SAM environment.
Date: March 1, 2008
Creator: Blair, N.; Mehos, M. & Christensen, C.
System: The UNT Digital Library
Fox-2 Splicing Factor Binds to a Conserved Intron Motif to PromoteInclusion of Protein 4.1R Alternative Exon 16 (open access)

Fox-2 Splicing Factor Binds to a Conserved Intron Motif to PromoteInclusion of Protein 4.1R Alternative Exon 16

Activation of protein 4.1R exon 16 (E16) inclusion during erythropoiesis represents a physiologically important splicing switch that increases 4.1R affinity for spectrin and actin. Previous studies showed that negative regulation of E16 splicing is mediated by the binding of hnRNP A/B proteins to silencer elements in the exon and that downregulation of hnRNP A/B proteins in erythroblasts leads to activation of E16 inclusion. This paper demonstrates that positive regulation of E16 splicing can be mediated by Fox-2 or Fox-1, two closely related splicing factors that possess identical RNA recognition motifs. SELEX experiments with human Fox-1 revealed highly selective binding to the hexamer UGCAUG. Both Fox-1 and Fox-2 were able to bind the conserved UGCAUG elements in the proximal intron downstream of E16, and both could activate E16 splicing in HeLa cell co-transfection assays in a UGCAUG-dependent manner. Conversely, knockdown of Fox-2 expression, achieved with two different siRNA sequences resulted in decreased E16 splicing. Moreover, immunoblot experiments demonstrate mouse erythroblasts express Fox-2, but not Fox-1. These findings suggest that Fox-2 is a physiological activator of E16 splicing in differentiating erythroid cells in vivo. Recent experiments show that UGCAUG is present in the proximal intron sequence of many tissue-specific alternative exons, and …
Date: March 1, 2006
Creator: Ponthier, Julie L.; Schluepen, Christina; Chen, Weiguo; Lersch,Robert A.; Gee, Sherry L.; Hou, Victor C. et al.
System: The UNT Digital Library
Evidence for production of single top quarks (open access)

Evidence for production of single top quarks

We present first evidence for the production of single top quarks in the D0 detector at the Fermilab Tevatron p{bar p} collider. The standard model predicts that the electroweak interaction can produce a top quark together with an antibottom quark or light quark, without the antiparticle top quark partner that is always produced from strong coupling processes. Top quarks were first observed in pair production in 1995, and since then, single top quark production has been searched for in ever larger datasets. In this analysis, we select events from a 0.9 fb{sup -1} dataset that have an electron or muon and missing transverse energy from the decay of a W boson from the top quark decay, and two, three, or four jets, with one or two of the jets identified as originating from a b hadron decay. The selected events are mostly backgrounds such as W+jets and t{bar t} events, which we separate from the expected signals using three multivariate analysis techniques: boosted decision trees, Bayesian neural networks, and matrix element calculations. A binned likelihood fit of the signal cross section plus background to the data from the combination of the results from the three analysis methods gives a cross …
Date: March 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
System: The UNT Digital Library
Greening the U.S. House of Representatives (open access)

Greening the U.S. House of Representatives

The Greening the Capitol initiative was launched in March, 2007 with the threefold goals of making the U.S. House of Representatives: 1) carbon neutral within 18 months, 2) reducing energy use by 50percent in ten years, and 3) becoming a model of sustainable operations. We report on the recommendations to meet these goals, looking at the targets of opportunity at the Capitol Power Plant, the existing buildings, and the overall operations of the complex. Our findings have shown that these goals are achievable, and that through an integrated approach the savings in carbon and energy can be met. Specific examples include the lighting retrofits in the House offices, parking areas, and the Capitol dome; the retrofits to the HVAC systems and controls, including duct sealing, improving the efficiency of the energy and water use in the food service areas; and improved operations of the steam and chilled water distribution system. A key aspect has been better tracking and feedback to the building operators of the actual energy consumption. We report on the technical opportunities presented by these historic and symbolic buildings in becoming models of sustainability.
Date: March 1, 2008
Creator: Diamond, Rick; Diamond, Rick & Payne, Christopher
System: The UNT Digital Library
A qualitative assessment of microclimatic perturbations in atunnel (open access)

A qualitative assessment of microclimatic perturbations in atunnel

Understanding microclimate dynamics in tunnels is importantfor designing and maintaining underground facilities. For example, in thegeological disposal of radioactive materials, condensation of vaporshould be minimized as it can accelerate waste package corrosion andradionuclide release. While microclimate dynamics are known to bedominated by the advection of heat and moisture, additional factors mayalso be important, such as the presence of fractures or faults. Wepresent a relatively inexpensive method to assess microclimaticperturbations within a tunnel. By combining standard temperature andrelative humidity sensors with low-cost sensors designed to detectchanges in condensation, we monitored microclimate dynamics along atunnel at the proposed geological repository at Yucca Mountain, Nevada.We observed significant differences in the pattern of condensation in afaulted zone relative to that of a nonfaulted zone, suggesting that themicroclimate dynamics of excavated cavities in fractured, partiallysaturated rocks can be highly complex.
Date: March 1, 2007
Creator: Salve, R. & Kowalsky, M. B.
System: The UNT Digital Library
Towards a deeper insight into strongly correlated electron systems- the symbiosis between experiment and theory (open access)

Towards a deeper insight into strongly correlated electron systems- the symbiosis between experiment and theory

None
Date: March 1, 2007
Creator: Fischer, Peter
System: The UNT Digital Library
Synthesis Gas Production by Rapid Solar Thermal Gasification of Corn Stover (open access)

Synthesis Gas Production by Rapid Solar Thermal Gasification of Corn Stover

Biomass resources hold great promise as renewable fuel sources for the future, and there exists great interest in thermochemical methods of converting these resources into useful fuels. The novel approach taken by the authors uses concentrated solar energy to efficiently achieve temperatures where conversion and selectivity of gasification are high. Use of solar energy removes the need for a combustion fuel and upgrades the heating value of the biomass products. The syngas product of the gasification can be transformed into a variety of fuels useable with today?s infrastructure. Gasification in an aerosol reactor allows for rapid kinetics, allowing efficient utilization of the incident solar radiation and high solar efficiency.
Date: March 1, 2008
Creator: Perkins, C. M.; Woodruff, B.; Andrews, L.; Lichty, P.; Lancaster, B.; Weimer, A. W. et al.
System: The UNT Digital Library
Social Media's New Role in Emergency Management (open access)

Social Media's New Role in Emergency Management

As technology continues to evolve, emergency management organizations must adapt to new ways of responding to the media and public. This paper examines a brief overview of social media's new role in emergency management. This includes definitions of social media, the benefits of utilizing social media, examples of social media being used and finally a discussion of how agencies, such as Department of Energy national laboratories, can begin including social media in their emergency management plans.
Date: March 1, 2008
Creator: Huffman, Ethan & Prentice, Sara
System: The UNT Digital Library
Search for Standard Model Higgs Boson Production in Association with a W Boson at CDF (open access)

Search for Standard Model Higgs Boson Production in Association with a W Boson at CDF

We present a search for standard model Higgs boson production in association with a W boson in proton-antiproton collisions (p{bar p} {yields} W{sup {+-}}H {yields} {ell}{nu}b{bar b}) at a center of mass energy of 1.96 TeV. The search employs data collected with the CDF II detector which correspond to an integrated luminosity of approximately 1 fb{sup -1}. We select events consistent with a signature of a single lepton (e{sup {+-}}/{mu}{sup {+-}}), missing transverse energy, and two jets. Jets corresponding to bottom quarks are identified with a secondary vertex tagging method and a neural network filter technique. The observed number of events and the dijet mass distributions are consistent with the standard model background expectations, and we set 95% confidence level upper limits on the production cross section times branching ratio ranging from 3.9 to 1.3 pb for Higgs boson masses from 110 to 150 GeV/c{sup 2}, respectively.
Date: March 1, 2008
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Adelman, J.; /Chicago U., EFI; Akimoto, T.; U., /Tsukuba et al.
System: The UNT Digital Library
Fossil and Contemporary Fine Carbon Fractions at 12 Rural and Urban Sites in the United States (open access)

Fossil and Contemporary Fine Carbon Fractions at 12 Rural and Urban Sites in the United States

Fine particulate matter collected at two urban, four near-urban, and six remote sites throughout the United States were analyzed for total carbon (TC) and radiocarbon ({sup 14}C). Samples were collected at most sites for both a summer and winter season. The radiocarbon was used to partition the TC into fossil and contemporary fractions. On average, contemporary carbon composed about half of the carbon at the urban, {approx}70-97% at near-urban, and 82-100% at remote sites. At Phoenix, Arizona, and Seattle, Washington, one monitor was located within the urban center and one outside to assess the urban excess over background concentrations. During the summer the urban and rural sites had similar contemporary carbon concentrations. However, during the winter the urban sites had more than twice the contemporary carbon measured at the neighboring sites, indicating anthropogenic contributions to the contemporary carbon. The urban fossil carbon was 4-20 times larger than the neighboring rural sites for both seasons. Organic (OC) and elemental carbon (EC) from TOR analysis were available. These and the radiocarbon data were used to estimate characteristic fossil and contemporary EC/TC ratios for the winter and summer seasons. These ratios were applied to carbon data from the Interagency Monitoring of Protected Visual …
Date: March 1, 2007
Creator: Schichtel, B; Malm, W; Bench, G; Fallon, S; McDade, C & Chow, J
System: The UNT Digital Library
High-Resolution UV Relay Lens for Particle Size Distribution Measurements Using Holography (open access)

High-Resolution UV Relay Lens for Particle Size Distribution Measurements Using Holography

Shock waves passing through a metal sample can produce ejecta particulates at a metal-vacuum interface. Holography records particle size distributions by using a highpower, short-pulse laser to freeze particle motion. The sizes of the ejecta particles are recorded using an in-line Fraunhofer holography technique. Because the holographic plate would be destroyed in this energetic environment, a high-resolution lens has been designed to relay the interference fringes to a safe environment. Particle sizes within a 12-mm-diameter, 5-mm-thick volume are recorded on holographic film. To achieve resolution down to 0.5 microns, ultraviolet (UV) light (in this case supplied by a tripled Nd:YAG laser) is needed. The design and assembly of a nine-element lens that achieves >2000 lp/mm resolution and operates at f/0.85 will be described. To set up this lens system, a doublet lens is temporarily attached that enables operation with 532-nm (green) light and 1100 lp/mm resolution. Thus, the setup and alignment is performed with green light, but the dynamic recording is done with UV light. During setup, the 532-nm beam provides enough focus shift to accommodate the placement of a resolution pattern outside the ejecta volume; this resolution pattern does not interfere with the calibrated wires and pegs surrounding the …
Date: March 1, 2008
Creator: Malone, Robert M.; Frogget, Brent C.; Kaufman, Morris I.; Tibbits, Aric; Capelle, Gene A.; Grover, Mike et al.
System: The UNT Digital Library
Light quasiparticles dominate electronic transport in molecular crystal field-effect transistors (open access)

Light quasiparticles dominate electronic transport in molecular crystal field-effect transistors

We report on an infrared spectroscopy study of mobile holes in the accumulation layer of organic field-effect transistors based on rubrene single crystals. Our data indicate that both transport and infrared properties of these transistors at room temperature are governed by light quasiparticles in molecular orbital bands with the effective masses m[small star, filled]comparable to free electron mass. Furthermore, the m[small star, filled]values inferred from our experiments are in agreement with those determined from band structure calculations. These findings reveal no evidence for prominent polaronic effects, which is at variance with the common beliefs of polaron formation in molecular solids.
Date: March 1, 2007
Creator: Li, Z. Q.; Podzorov, V.; Sai, N.; Martin, Michael C.; Gershenson, M. E.; Di Ventra, M. et al.
System: The UNT Digital Library
Search for scalar top quarks in the acoplanar charm jets and missing transverse energy final state in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

Search for scalar top quarks in the acoplanar charm jets and missing transverse energy final state in p anti-p collisions at s**(1/2) = 1.96-TeV

None
Date: March 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
System: The UNT Digital Library
Corrosion behavior of iron and nickel base alloys under solid oxide fuel cell exposure conditions (open access)

Corrosion behavior of iron and nickel base alloys under solid oxide fuel cell exposure conditions

Topography and phase composition of the scales formed on commercial ferritic stainless steels and experimental low CTE nickel-based alloys were studied in atmospheres simulating solid oxide fuel cell (SOFC) environments. The materials were studied under dual environment conditions with air on one side of the sample and carbon monoxide on the other side at 750°C. Surface characterization techniques, such as scanning electron microscopy and X-ray diffraction analysis were used in this study.
Date: March 1, 2006
Creator: Ziomek-Moroz, M.; Holcomb, G. R.; Covino, B. S., Jr. & Bullard, S. J.
System: The UNT Digital Library
Development of a fracture network: a block and springs model (open access)

Development of a fracture network: a block and springs model

Since flow in fractured reservoirs is significantly enhanced by clusters of inter-connecting fractures, it's important to understand their inter-connectedness. In these fractured reservoirs, one often finds two sets of fractures due to two separate geologic events. We have developed a blocks and springs model to study how the second generation fractures intersect the first generation of. We find a percolation-like transition where the cluster size grows with increasing strain leading to system-spanning fractal clusters. Increasing the thickness of the layer being fractured leads to sparser system-spanning fracture clusters with smaller fractal dimension. We have studied how the thickness of the layer affects the fractal character of the fracture clusters as well as their number distribution, and the correlations within the large fracture cluster.
Date: March 1, 2008
Creator: Ferer, M. V.; Jozwick, A. & Smith, D. H.
System: The UNT Digital Library