Linear Multifrequency-Grey Acceleration Recast for Preconditioned Krylov Iterations (open access)

Linear Multifrequency-Grey Acceleration Recast for Preconditioned Krylov Iterations

None
Date: March 19, 2007
Creator: Morel, J E; Yang, T B & Warsa, J S
Object Type: Article
System: The UNT Digital Library
FRACTIONAL CRYSTALLIZATION FEED ENVELOPE (open access)

FRACTIONAL CRYSTALLIZATION FEED ENVELOPE

Laboratory work was completed on a set of evaporation tests designed to establish a feed envelope for the fractional crystallization process. The feed envelope defines chemical concentration limits within which the process can be operated successfully. All 38 runs in the half-factorial design matrix were completed successfully, based on the qualitative definition of success. There is no feed composition likely to be derived from saltcake dissolution that would cause the fractional crystallization process to not meet acceptable performance requirements. However, some compositions clearly would provide more successful operation than other compositions.
Date: March 19, 2008
Creator: DL, HERTING
Object Type: Report
System: The UNT Digital Library
Oncogene mRNA Imaging with Radionuclide-PNA-Peptides (open access)

Oncogene mRNA Imaging with Radionuclide-PNA-Peptides

New cancer gene hybridization probes to carry radionuclides were made. Noninvasive technetium-99m gamma imaging of CCND1 cancer gene activity in human breast cancer tumors in mice was demonstrated, followed by noninvasive technetium-99m imaging of MYC cancer gene activity. Noninvasive imaging of CCND1 cancer gene activity in human breast cancer tumors in mice was demonstrated with a positron-emitting copper-64 probe, followed by noninvasive positron imaging of IRS1 cancer gene activity.
Date: March 19, 2008
Creator: Wickstrom, Eric
Object Type: Report
System: The UNT Digital Library
SURFACE GEOPHYSICAL EXPLORATION OF TX AND TY TANK FARMS AT THE HANFORD SITE RESULTS OF BACKGROUND CHARACTERIZATION WITH MAGNETICS AND ELECTROMAGNETIC (open access)

SURFACE GEOPHYSICAL EXPLORATION OF TX AND TY TANK FARMS AT THE HANFORD SITE RESULTS OF BACKGROUND CHARACTERIZATION WITH MAGNETICS AND ELECTROMAGNETIC

None
Date: March 19, 2008
Creator: DA, MYERS; D, RUCKER; M, LEBITT; B, CUBBAGE & HENDERSON
Object Type: Report
System: The UNT Digital Library
Survey of the ATLAS Pixel Detector Components (open access)

Survey of the ATLAS Pixel Detector Components

This document provides a description of the survey performed on different componentsof the ATLAS Pixel Detector at different stages of its assembly.
Date: March 19, 2008
Creator: Andreazza, Attilio; Kostyukhim, Vadim & Madaras, Ronald
Object Type: Report
System: The UNT Digital Library
Investigation of the Richtmyer-Meshkov instability (open access)

Investigation of the Richtmyer-Meshkov instability

The present research program is centered on the experimental and numerical study of the hydrodynamics of shock-accelerated spherical density inhomogeneities. These flows are part of a broader category of shock-induced mixing flows that play a critical role in the implosion of D-T pellets in laser-driven ICF experiments. For the past year, our work has consisted of both experimental and numerical activities which were presented at two conferences and resulted in the publication of one journal article and the submission of a second one. The papers from one of the conferences are inlcuded here.
Date: March 19, 2007
Creator: Bonazza, Riccardo; Anderson, Mark & Oakley, Jason
Object Type: Report
System: The UNT Digital Library
Science & Technology Review May/June 2008 (open access)

Science & Technology Review May/June 2008

This month's issue has the following articles: (1) Biomedical Technology Has a Home at Livermore--Commentary by Cherry A. Murray; (2) Shaping the Future of Aneurysm Treatments--Livermore foam devices may offer significant advantages for treating some forms of aneurysms; (3) Ring around a Stellar Shell: A Tale of Scientific Serendipity--Using a three-dimensional model, Livermore scientists have solved a long-standing puzzle of stellar evolution; and (4) On Assignment in Washington, DC--Livermore personnel in Washington, DC, support federal sponsors and become valuable assets to Laboratory programs.
Date: March 19, 2008
Creator: Chinn, D J
Object Type: Report
System: The UNT Digital Library
Plutonium/High-Level Vitrified Waste Bdbe Dose Calculation (open access)

Plutonium/High-Level Vitrified Waste Bdbe Dose Calculation

In accordance with the Nuclear Waste Policy Amendments Act of 1987, Yucca Mountain was designated as the site to be investigated as a potential repository for the disposal of high-level radioactive waste. The Yucca Mountain site is an undeveloped area located on the southwestern edge of the Nevada Test Site (NTS), about 100 miles northwest of Las Vegas. The site currently lacks rail service or an existing right-of-way. If the Yucca Mountain site is found suitable for the repository, rail service is desirable to the Office of Civilian Waste Management (OCRWM) Program because of the potential of rail transportation to reduce costs and to reduce the number of shipments relative to highway transportation. A Preliminary Rail Access Study evaluated 13 potential rail spur options. Alternative routes within the major options were also developed. Each of these options was then evaluated for potential land use conflicts and access to regional rail carriers. Three potential routes having few land use conflicts and having access to regional carriers were recommended for further investigation. Figure 1-1 shows these three routes. The Jean route is estimated to be about 120 miles long, the Carlin route to be about 365 miles long, and Caliente route to …
Date: March 19, 2003
Creator: Richardson, D. C.
Object Type: Report
System: The UNT Digital Library
Remaining Sites Verification Package for the 100-D-2 Lead Sheeting Waste Site, Waste Site Reclassification Form 2007-030 (open access)

Remaining Sites Verification Package for the 100-D-2 Lead Sheeting Waste Site, Waste Site Reclassification Form 2007-030

The 100-D-2 Lead Sheeting waste site was located approximately 50 m southwest of the 185-D Building and approximately 16 m north of the east/west oriented road. The site consisted of a lead sheet covering a concrete pad. In accordance with this evaluation, the verification sampling results support a reclassification of this site to Interim Closed Out. The results of verification sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.
Date: March 19, 2008
Creator: Dittmer, L. M.
Object Type: Report
System: The UNT Digital Library
Kahler stabilized, modular invariant heterotic string models (open access)

Kahler stabilized, modular invariant heterotic string models

We review the theory and phenomenology of effective supergravity theories based on orbifold compactifications of the weakly-coupled heterotic string. In particular, we consider theories in which the four-dimensional theory displays target space modular invariance and where the dilatonic mode undergoes Kahler stabilization. A self-contained exposition of effective Lagrangian approaches to gaugino condensation and heterotic string theory is presented, leading to the development of the models of Binétruy, Gaillard and Wu. Various aspects of the phenomenology of this class of models are considered. These include issues of supersymmetry breaking and superpartner spectra, the role of anomalous U(1) factors, issues of flavor and R-parity conservation, collider signatures, axion physics, and early universe cosmology. For the vast majority of phenomenological considerations the theories reviewed here compare quite favorably to other string-derived models in the literature. Theoretical objections to the framework and directions for further research are identified and discussed.
Date: March 19, 2007
Creator: Gaillard, Mary K.; Gaillard, Mary K. & Nelson, Brent D.
Object Type: Article
System: The UNT Digital Library
Physical Property Changes in Aging Plutonium Alloys (open access)

Physical Property Changes in Aging Plutonium Alloys

None
Date: March 19, 2008
Creator: Chung, B W; Thompson, S R & Hiromoto, D S
Object Type: Article
System: The UNT Digital Library
Second Research Coordination Meeting on Reference Database for Neutron Activation Analysis -- Summary Report (open access)

Second Research Coordination Meeting on Reference Database for Neutron Activation Analysis -- Summary Report

The second meeting of the Co-ordinated Research Project on"Reference Database for Neutron Activation Analysis" was held at the IAEA, Vienna from 7-9 May, 2007. A summary of the presentations made by participants is given, along with reports on specifically assigned tasks and subsequent discussions. In order to meet the overall objectives of this CRP, the outputs have been reiterated and new task assignments made.
Date: March 19, 2008
Creator: Firestone, Richard B. & Kellett, Mark A.
Object Type: Report
System: The UNT Digital Library
Measurement of Electron Clouds in Large Accelerators by Microwave Dispersion (open access)

Measurement of Electron Clouds in Large Accelerators by Microwave Dispersion

Clouds of low energy electrons in the vacuum beam pipes of accelerators of positively charged particle beams present a serious limitation for operation at high currents. Furthermore, it is difficult to probe their density over substantial lengths of the beam pipe. We have developed a novel technique to directly measure the electron cloud density via the phase shift induced in a TE wave transmitted over a section of the accelerator and used it to measure the average electron cloud density over a 50 m section in the positron ring of the PEP-II collider at the Stanford Linear Accelerator Center.
Date: March 19, 2008
Creator: De Santis, S.; Byrd, J. M.; Caspers, F.; Krasnykh, A.; Kroyer, T.; Pivi, M. T. F. et al.
Object Type: Article
System: The UNT Digital Library
A Detailed Modeling Study of Propane Oxidation (open access)

A Detailed Modeling Study of Propane Oxidation

A detailed chemical kinetic mechanism has been used to simulate ignition delay times recorded by a number of experimental shock tube studies over the temperature range 900 {le} T {le} 1800 K, in the pressure range 0.75-40 atm and in the equivalence ratio range 0.5 {le} {phi} {le} 2.0. Flame speed measurements at 1 atm in the equivalence ratio range 0.4 {le} {phi} {le} 1.8 have also been simulated. Both of these data sets, particularly those recorded at high pressure, are of particular importance in validating a kinetic mechanism, as internal combustion engines operate at elevated pressures and temperatures and rates of fuel oxidation are critical to efficient system operation. Experiments in which reactant, intermediate and product species were quantitatively recorded, versus temperature in a jet-stirred reactor (JSR) and versus time in a flow reactor are also simulated. This data provide a stringent test of the kinetic mechanism as it must reproduce accurate quantitative profiles for all reactant, intermediate and product species. The JSR experiments were performed in the temperature range 1000-1110 K, in the equivalence ratio range 0.5 {le} {phi} {le} 4.0, at a pressure of 5 atm. These experiments are complemented by those carried out in a flow …
Date: March 19, 2004
Creator: Westbrook, C. K.; Jayaweera, T. M.; Pitz, W. J. & Curran, H. J.
Object Type: Article
System: The UNT Digital Library
A crust and upper mantle model of Eurasia and North Africa for Pn travel time calculation (open access)

A crust and upper mantle model of Eurasia and North Africa for Pn travel time calculation

We develop a Regional Seismic Travel Time (RSTT) model and methods to account for the first-order effect of the three-dimensional crust and upper mantle on travel times. The model parameterization is a global tessellation of nodes with a velocity profile at each node. Interpolation of the velocity profiles generates a 3-dimensional crust and laterally variable upper mantle velocity. The upper mantle velocity profile at each node is represented as a linear velocity gradient, which enables travel time computation in approximately 1 millisecond. This computational speed allows the model to be used in routine analyses in operational monitoring systems. We refine the model using a tomographic formulation that adjusts the average crustal velocity, mantle velocity at the Moho, and the mantle velocity gradient at each node. While the RSTT model is inherently global and our ultimate goal is to produce a model that provides accurate travel time predictions over the globe, our first RSTT tomography effort covers Eurasia and North Africa, where we have compiled a data set of approximately 600,000 Pn arrivals that provide path coverage over this vast area. Ten percent of the tomography data are randomly selected and set aside for testing purposes. Travel time residual variance for …
Date: March 19, 2009
Creator: Myers, S; Begnaud, M; Ballard, S; Pasyanos, M; Phillips, W S; Ramirez, A et al.
Object Type: Article
System: The UNT Digital Library
Post-Closure Inspection Report for the Tonopah Test Range, Nevada, For Calendar Year 2008 (open access)

Post-Closure Inspection Report for the Tonopah Test Range, Nevada, For Calendar Year 2008

This report provides the results of the annual post-closure inspections conducted at the closed Corrective Action Unit (CAU) sites located on the Tonopah Test Range (TTR), Nevada. This report covers calendar year 2008 and includes inspection and repair activities completed at the following ten CAUs: #2; CAU 400: Bomblet Pit and Five Points Landfill (TTR) #2; CAU 404: Roller Coaster Lagoons and Trench (TTR) #2; CAU 407: Roller Coaster RadSafe Area (TTR) #2; CAU 423: Area 3 Underground Discharge Point, Building 0360 (TTR) #2; CAU 424: Area 3 Landfill Complexes (TTR) #2; CAU 426: Cactus Spring Waste Trenches (TTR) #2; CAU 427: Area 3 Septic Waste Systems 2, 6 (TTR) #2; CAU 453: Area 9 UXO Landfill (TTR) #2; CAU 484: Surface Debris, Waste Sites, and Burn Area (TTR) #2; CAU 487: Thunderwell Site (TTR)
Date: March 19, 2009
Creator: National Security Technologies, LLC
Object Type: Report
System: The UNT Digital Library
Annealing as grown large volume CZT single crystals increased spectral resolution (open access)

Annealing as grown large volume CZT single crystals increased spectral resolution

The spectroscopic performance of current large-volume Cadmium 10% Zinc Telluride, Cd{sub 0.9}Zn{sub 0.1}Te, (CZT) detectors is impaired by cumulative effect of tellurium precipitates (secondary phases) presented in CZT single-crystal grown by low-pressure Bridgman techniques(1). This statistical effect may limit the energy resolution of large-volume CZT detectors (typically 2-5% at 662 keV for 12-mm thick devices). The stochastic nature of the interaction prevents the use of any electronic or digital charge correction techniques without a significant reduction in the detector efficiency. This volume constraint hampers the utility of CZT since the detectors are inefficient at detecting photons >1MeV and/or in low fluency situations. During the project, seven runs CZT ingots have been grown, in these ingots the indium dopant concentrations have been changed in the range between 0.5ppm to 6ppm. The I-R mapping imaging method has been employed to study the Te-precipitates. The Teprecipitates in as-grown CZT wafers, and after annealing wafers have been systematically studied by using I-R mapping system (home installed, resolution of 1.5 {micro}m). We employed our I-R standard annealing CZT (Zn=4%) procedure or two-steps annealing into radiation CZT (Zn=10%), we achieved the 'non'-Te precipitates (size < 1 {micro}m) CZT n+-type with resistivity > 10{sup 9-10} {Omega}-cm. We …
Date: March 19, 2008
Creator: Li, Dr. Longxia
Object Type: Report
System: The UNT Digital Library
Structural characterization of terrestrial microbial Mn oxides from Pinal Creek, AZ (open access)

Structural characterization of terrestrial microbial Mn oxides from Pinal Creek, AZ

The microbial catalysis of Mn(II) oxidation is believed to be a dominant source of abundant sorption- and redox-active Mn oxides in marine, freshwater, and subsurface aquatic environments. In spite of their importance, environmental oxides of known biogenic origin have generally not been characterized in detail from a structural perspective. Hyporheic zone Mn oxide grain coatings at Pinal Creek, Arizona, a metals-contaminated stream, have been identified as being dominantly microbial in origin and are well studied from bulk chemistry and contaminant hydrology perspectives. This site thus presents an excellent opportunity to study the structures of terrestrial microbial Mn oxides in detail. XRD and EXAFS measurements performed in this study indicate that the hydrated Pinal Creek Mn oxide grain coatings are layer-type Mn oxides with dominantly hexagonal or pseudo-hexagonal layer symmetry. XRD and TEM measurements suggest the oxides to be nanoparticulate plates with average dimensions on the order of 11 nm thick x 35 nm diameter, but with individual particles exhibiting thickness as small as a single layer and sheets as wide as 500 nm. The hydrated oxides exhibit a 10-A basal-plane spacing and turbostratic disorder. EXAFS analyses suggest the oxides contain layer Mn(IV) site vacancy defects, and layer Mn(III) is inferred …
Date: March 19, 2008
Creator: Bargar, John; Fuller, Christopher; Marcus, Matthew A.; Brearley, Adrian J.; Perez De la Rosa, M.; Webb, Samuel M. et al.
Object Type: Article
System: The UNT Digital Library
The Hierarchical Build-Up of Massive Galaxies And the Intracluster Light Since z=1 (open access)

The Hierarchical Build-Up of Massive Galaxies And the Intracluster Light Since z=1

We use a set of simulation-based models for the dissipationless evolution of galaxies since z = 1 to constrain the fate of accreted satellites embedded in dark matter subhalos. These models assign stellar mass to dark matter halos at z = 1 by relating the observed galaxy stellar mass function (GSMF) to the halo+subhalo mass function monotonically. The evolution of the stellar mass content is then followed using halo merger trees extracted from N-body simulations. Our models are differentiated only in the fate assigned to satellite galaxies once subhalos, within which satellites are embedded, disrupt. These models are confronted with the observed evolution in the massive end of the GSMF, the z {approx} 0 brightest cluster galaxy (BCG)-cluster mass relation, and the combined BCG and intracluster light (ICL) luminosity distribution--all observables expected to evolve approximately dissipationlessly since z = 1. The combined observational constraints favor a model in which the vast majority ({approx}> 80%) of satellite stars from disrupted subhalos go into the ICL (operationally defined here as light below a surface brightness cut of {mu}{sub i} {approx} 23mag arcsec{sup -2}). Conversely, models that leave behind a significant population of satellite galaxies once the subhalo has disrupted are strongly disfavored, …
Date: March 19, 2007
Creator: Conroy, Charlie; Wechsler, Risa H. & Kravtsov, Andrey V.
Object Type: Article
System: The UNT Digital Library
Development of a Simple Radioactive marker System to Reduce Positioning Errors in Radiation Treatment (open access)

Development of a Simple Radioactive marker System to Reduce Positioning Errors in Radiation Treatment

The objective of this research is to implement an inexpensive, quick and simple monitor that provides an accurate indication of proper patient position during the treatment of cancer by external beam X-ray radiation and also checks for any significant changes in patient anatomy. It is believed that this system will significantly reduce the treatment margin, provide an additional, independent quality assurance check of positioning accuracy prior to all treatments and reduce the probability of misadministration of therapeutic dose.
Date: March 19, 2007
Creator: Miller, William H. & Palta, Dr. Jatinder
Object Type: Report
System: The UNT Digital Library
Early Computing and Its Impact on Lawrence Livermore National Laboratory (open access)

Early Computing and Its Impact on Lawrence Livermore National Laboratory

None
Date: March 19, 2007
Creator: Lokke, W.
Object Type: Report
System: The UNT Digital Library
A Symposium in Honor of William A. Lester, Jr. on His 70thBirthday (open access)

A Symposium in Honor of William A. Lester, Jr. on His 70thBirthday

None
Date: March 19, 2007
Creator: Lester, William A., Jr.
Object Type: Article
System: The UNT Digital Library
Applications of Cfd Method to Gas Mixing Analysis in a Large-Scaled Tank (open access)

Applications of Cfd Method to Gas Mixing Analysis in a Large-Scaled Tank

The computational fluid dynamics (CFD) modeling technique was applied to the estimation of maximum benzene concentration for the vapor space inside a large-scaled and high-level radioactive waste tank at Savannah River site (SRS). The objective of the work was to perform the calculations for the benzene mixing behavior in the vapor space of Tank 48 and its impact on the local concentration of benzene. The calculations were used to evaluate the degree to which purge air mixes with benzene evolving from the liquid surface and its ability to prevent an unacceptable concentration of benzene from forming. The analysis was focused on changing the tank operating conditions to establish internal recirculation and changing the benzene evolution rate from the liquid surface. The model used a three-dimensional momentum coupled with multi-species transport. The calculations included potential operating conditions for air inlet and exhaust flows, recirculation flow rate, and benzene evolution rate with prototypic tank geometry. The flow conditions are assumed to be fully turbulent since Reynolds numbers for typical operating conditions are in the range of 20,000 to 70,000 based on the inlet conditions of the air purge system. A standard two-equation turbulence model was used. The modeling results for the typical …
Date: March 19, 2007
Creator: Lee, S. & Richard Dimenna, R.
Object Type: Article
System: The UNT Digital Library
The Molecular Basis for Metabolic and Energetic Diversity (open access)

The Molecular Basis for Metabolic and Energetic Diversity

We have used experimental and computational analysis of R. sphaeroides photosynthesis and other gene expression networks (Kaplan, Gomelsky, Donohue) (3-9, 12, 13, 15-18, 20). We have identified many new candidate photosynthesis genes with expression patterns that varied as a function of light intensity. Results from these experiments suggest there are many more light-regulated aspects of the photosynthetic lifestyle of this bacterium than previously appreciated. Ongoing genetic analysis confirms that mutations in some of these newly-identified photosynthesis block the ability of cells to use solar energy in the laboratory. We also carried out transcriptome and computational analysis of individual R. sphaeroides regulons. This identified additional genes that are directly regulated by individual transcription factors and refined the consensus sequence for master regulators of photosystem development. We also showed that PpsR indirectly regulates genes that do not contain the PpsR-binding sites, e.g. puf and puhA operons. This suggests that PpsR plays a more global role as a regulator of photosystem development than what was assumed before. A similar computational and microarray analysis of PrrA target genes has identified many new candidate promoters that are controlled by this master regulator of photosynthesis. We have begun bioinformatic, genetic and biochemical experiments aimed at elucidating …
Date: March 19, 2007
Creator: Timothy Donohue, PI
Object Type: Report
System: The UNT Digital Library