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An Explicit Runge-Kutta Iteration for Diffusion in the Low MachNumber Combustion Code (open access)

An Explicit Runge-Kutta Iteration for Diffusion in the Low MachNumber Combustion Code

This report describes the implementation of a Runge-Kuttaiterationboth for mixture-averaged and for multicomponent diffusion withDufourand Soret effects in the low Mach number combustioncode.
Date: August 29, 2007
Creator: Grcar, Joseph F.
Object Type: Report
System: The UNT Digital Library
Annual Report of the International Nuclear Energy Research Initiative Osmose Project (FY06). (open access)

Annual Report of the International Nuclear Energy Research Initiative Osmose Project (FY06).

The goal of the OSMOSE program is to measure the reactivity effect of minor actinides in known neutron spectra of interest to the Generation-IV reactor program and other programs and to create a database of these results for use as an international benchmark for the minor actinides. The results are then compared to calculation models to verify and validate integral absorption cross-sections for the minor actinides. The OSMOSE program includes all aspects of the experimental program--including the fabrication of fuel pellets and samples, the oscillation of the samples in the MINERVE reactor for the measurement of the reactivity effect, reactor physics modeling of the MINERVE reactor, and the data analysis and interpretation of the experimental results.
Date: August 29, 2007
Creator: Klann, R. T.; Hudelot, J. P.; Drin, N.; Zhong, Z.; Division, Nuclear Engineering & Atomique, Commissariat a l'Energie
Object Type: Report
System: The UNT Digital Library
Highly Potent, Water Soluble Benzimidazole Antagonist for Activated (alpha)4(beta)1 Integrin (open access)

Highly Potent, Water Soluble Benzimidazole Antagonist for Activated (alpha)4(beta)1 Integrin

The cell surface receptor {alpha}{sub 4}{beta}{sub 1} integrin, activated constitutively in lymphoma, can be targeted with the bisaryl urea peptidomimetic antagonist 1 (LLP2A). However, concerns on its preliminary pharmacokinetic (PK) profile provided an impetus to change the pharmacophore from a bisaryl urea to a 2-arylaminobenzimidazole moiety resulting in improved solubility while maintaining picomolar potency [5 (KLCA4); IC{sub 50} = 305 pM]. With exceptional solubility, this finding has potential for improving PK to help diagnose and treat lymphomas.
Date: August 29, 2007
Creator: Carpenter, R. D.; Andrei, M.; Lau, E. Y.; Lightstone, F. C.; Liu, R.; Lam, K. S. et al.
Object Type: Article
System: The UNT Digital Library
Sensitivity and representativity analysis of past experiments with respect to ABTR system. (open access)

Sensitivity and representativity analysis of past experiments with respect to ABTR system.

A comprehensive validation analysis has been performed that incorporates representativity of multiple parameters, experiments, reference designs, and adjustment of the nuclear data. The work involves a new representativity study among selected reactor designs and several experiments. Application, using existing experiments, to reference design like the ABTR and the SFR has demonstrated that it is possible to achieve a significant reduction of uncertainty on the main integral parameters of interest for their neutronic design. This is possible when the set of available experiments are relevant (i.e. representative of the reference designs), of good quality (i.e. of reduced uncertainty on experimental results), and consistent (i.e. not providing conflictive information).
Date: August 29, 2007
Creator: Aliberti, G.; Palmiotti, G. & Salvatores, M.
Object Type: Report
System: The UNT Digital Library
Characterization of the Structure of Cation-DopedBacteriogenic Uranium Oxides using X-Ray Diffraction (open access)

Characterization of the Structure of Cation-DopedBacteriogenic Uranium Oxides using X-Ray Diffraction

Remediation of uranium contamination in subsurface groundwater has become imperative as previous research and manufacturing involving radionuclides has led to contamination of groundwater sources. A possible in situ solution for sequestration of uranium is a bacterial process in which Shewanella oneidensis MR-1 reduces the soluble (and thus mobile) U(VI) oxidation state into the less mobile UO{sub 2} crystalline phase. However, the long term stability of the UO2 compound must be studied as oxidative conditions could return it back into the U(VI) state. Incorporation of other cations into the structure during manufacture of the UO{sub 2} could alter the dissolution behavior. A wide angle x-ray scattering (WAXS) experiment was performed to determine whether or not calcium, manganese, and magnesium are incorporated into this structure. If so, the substituted atoms would cause a contraction or expansion in the lattice because of their differing size, causing the lattice constant to be altered. After several stages of data reduction, the WAXS diffraction peaks were fit using the Le Bail fit method in order to determine the lattice constant. Initial results suggest that there may be incorporation of manganese into the UO{sub 2} structure due to a .03 Angstrom decrease in lattice constant, but more …
Date: August 29, 2007
Creator: Stahlman, Jonathan M. & /SLAC, /Carnegie Mellon U.
Object Type: Report
System: The UNT Digital Library
The Color Glass Condensate and the Glasma: Two Lectures. (open access)

The Color Glass Condensate and the Glasma: Two Lectures.

These two lectures concern the Color Glass Condensate and the Glasma. These are forms of matter which might be studied in high energy hadronic collisions. The Color Glass Condensate is high energy density gluonic matter. It constitutes the part of a hadron wave function important for high energy processes. The Glasma is matter produced from the Color Glass Condensate in the first instants after a collision of two high energy hadrons. Both types of matter are associated with coherent fields. The Color Glass Condensate is static and related to a hadron wavefunction, where the Glasma is transient and evolves quickly after a collision. I present the properties of such matter, and some aspects of what is known of their properties.
Date: August 29, 2007
Creator: McLerran, L.
Object Type: Article
System: The UNT Digital Library
High Relaxivity Gadolinium Hydroxypyridonate-Viral Capsid Conjugates: Nano-sized MRI Contrast Agents (open access)

High Relaxivity Gadolinium Hydroxypyridonate-Viral Capsid Conjugates: Nano-sized MRI Contrast Agents

High relaxivity macromolecular contrast agents based on the conjugation of gadolinium chelates to the interior and exterior surfaces of MS2 viral capsids are assessed. The proton nuclear magnetic relaxation dispersion (NMRD) profiles of the conjugates show up to a five-fold increase in relaxivity, leading to a peak relaxivity (per Gd{sup 3+} ion) of 41.6 mM{sup -1}s{sup -1} at 30 MHz for the internally modified capsids. Modification of the exterior was achieved through conjugation to flexible lysines, while internal modification was accomplished by conjugation to relatively rigid tyrosines. Higher relaxivities were obtained for the internally modified capsids, showing that (1) there is facile diffusion of water to the interior of capsids and (2) the rigidity of the linker attaching the complex to the macromolecule is important for obtaining high relaxivity enhancements. The viral capsid conjugated gadolinium hydroxypyridonate complexes appear to possess two inner-sphere water molecules (q = 2) and the NMRD fittings highlight the differences in the local motion for the internal ({tau}{sub RI} = 440 ps) and external ({tau}{sub RI} = 310 ps) conjugates. These results indicate that there are significant advantages of using the internal surface of the capsids for contrast agent attachment, leaving the exterior surface available for …
Date: August 29, 2007
Creator: Meux, Susan C.; Datta, Ankona; Hooker, Jacob M.; Botta, Mauro; Francis, Matthew B.; Aime, Silvio et al.
Object Type: Article
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 38, No. 354, Ed. 1 Wednesday, August 29, 2007 (open access)

Greensheet (Houston, Tex.), Vol. 38, No. 354, Ed. 1 Wednesday, August 29, 2007

Free weekly newspaper that includes business and classified advertising.
Date: August 29, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Cherokeean Herald (Rusk, Tex.), Vol. 158, No. 27, Ed. 1 Wednesday, August 29, 2007 (open access)

Cherokeean Herald (Rusk, Tex.), Vol. 158, No. 27, Ed. 1 Wednesday, August 29, 2007

Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.
Date: August 29, 2007
Creator: Whitehead, Marie
Object Type: Newspaper
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 91, No. 117, Ed. 1 Wednesday, August 29, 2007 (open access)

North Texas Daily (Denton, Tex.), Vol. 91, No. 117, Ed. 1 Wednesday, August 29, 2007

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state and campus news along with advertising.
Date: August 29, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
China-U.S. Trade Issues (open access)

China-U.S. Trade Issues

None
Date: August 29, 2007
Creator: Morrison, Wayne M.
Object Type: Report
System: The UNT Digital Library
Migrant and Seasonal Agricultural Workers: Protective Statutes (open access)

Migrant and Seasonal Agricultural Workers: Protective Statutes

None
Date: August 29, 2007
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Trade Promotion Authority (TPA) Renewal: Core Labor Standards Issues (open access)

Trade Promotion Authority (TPA) Renewal: Core Labor Standards Issues

None
Date: August 29, 2007
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Managing Electronic Waste: An Analysis of State E-Waste Legislation (open access)

Managing Electronic Waste: An Analysis of State E-Waste Legislation

In 2005, two congressional hearings were held to explore issues associated with e-waste, and the Congressional E-Waste Working Group was formed. One goal common to both the hearings and the establishment of the working group was to explore potential national solutions to the e-waste management issue. With increased legislative activity in the states, it is anticipated that stakeholders will increase their call for federal legislation regarding e-waste management. To illustrate the issues associated with individual state action, this report discusses the key issues that have led to state action, describes common elements in state waste laws and proposals, and provides an overview of each enacted state law.
Date: August 29, 2007
Creator: Luther, Linda
Object Type: Report
System: The UNT Digital Library
[Email from Lisa G. Thomas to Shannon] (open access)

[Email from Lisa G. Thomas to Shannon]

Email from Lisa G. Thomas to Shannon on August 29, 2007, regarding Shannon's resignation from Texas Stonewall Democratic Caucus.
Date: August 29, 2007
Creator: unknown
Object Type: Text
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 38, No. 353, Ed. 1 Wednesday, August 29, 2007 (open access)

Greensheet (Houston, Tex.), Vol. 38, No. 353, Ed. 1 Wednesday, August 29, 2007

Free weekly newspaper that includes business and classified advertising.
Date: August 29, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Greensheet (Dallas, Tex.), Vol. 31, No. 141, Ed. 1 Wednesday, August 29, 2007 (open access)

The Greensheet (Dallas, Tex.), Vol. 31, No. 141, Ed. 1 Wednesday, August 29, 2007

Free weekly newspaper that includes business and classified advertising.
Date: August 29, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
PLUTONIUM FEED IMPURITY TESTING IN A LANTHANIDE BOROSILICATE (LABS) GLASS (open access)

PLUTONIUM FEED IMPURITY TESTING IN A LANTHANIDE BOROSILICATE (LABS) GLASS

A vitrification technology utilizing a lanthanide borosilicate (LaBS) glass is a viable option for dispositioning excess weapons-useable plutonium that is not suitable for processing into mixed oxide (MOX) fuel. A significant effort to develop a glass formulation and vitrification process to immobilize plutonium was completed in the mid-1990s. The LaBS glass formulation was found to be capable of immobilizing in excess of 10 wt % Pu and to be tolerant of a range of impurities. A more detailed study is now needed to quantify the ability of the glass to accommodate the anticipated impurities associated with the Pu feeds now slated for disposition. The database of Pu feeds was reviewed to identify impurity species and concentration ranges for these impurities. Based on this review, a statistically designed test matrix of glass compositions was developed to evaluate the ability of the LaBS glass to accommodate the impurities. Sixty surrogate LaBS glass compositions were prepared in accordance with the statistically designed test matrix. The heterogeneity (e.g. degree of crystallinity) and durability (as measured by the Product Consistency Test - Method A (PCT-A)) of the glasses were used to assess the effects of impurities on glass quality.
Date: August 29, 2007
Creator: Marra, J; Kevin Fox, K; Elizabeth Hoffman, E; Tommy Edwards, T & Charles Crawford, C
Object Type: Article
System: The UNT Digital Library
Long-term X-ray Variability of NGC 4945 (open access)

Long-term X-ray Variability of NGC 4945

Though short-term X-ray variability has been studied for the active galaxy NGC 4945, long-term studies promise to contribute to our understanding of the processes involved in accretion onto supermassive black holes. In order to understand the relationship between black hole mass and breaks in the power spectral density (PSD), the long-term X-ray variability of NGC 4945 was studied over the energy range 8-30 keV. Observations occurred over the year 2006 using the Rossi X-ray Timing Explorer. The data was reduced using the package FTOOLS, most notably the scripts Rex and faxbary. Light curves were produced and a PSD was obtained using a Fast Fourier Transform algorithm. Preliminary studies of the light curve show greater X-ray variability at higher frequencies. This result complements previous studies of NGC 4945 by Martin Mueller. However, the PSD produced must go through further study before accurate results can be obtained. A way to account for the window function of the PSD must be found before the behavior at lower frequencies can be studied with accuracy and the relationship between black hole mass and the break in NGC 4945's PSD can be better understood. Further work includes exploration into ways to subtract the window function from …
Date: August 29, 2007
Creator: Miller, Amara
Object Type: Report
System: The UNT Digital Library
ILC Electron Source Injector Simuations (open access)

ILC Electron Source Injector Simuations

As part of the global project aimed at proposing an efficient design for the ILC (International Linear Collider), we simulated possible setups for the electron source injector, which will provide insight into how the electron injector for the ILC should be designed in order to efficiently accelerate the electron beams through the bunching system. This study uses three types of software: E-Gun to simulate electron beam emission, Superfish to calculate solenoidal magnetic fields, and GPT (General Particle Tracer) to trace charged particles after emission through magnetic fields and subharmonic bunchers. We performed simulations of the electron source injector using various electron gun bias voltages (140kV - 200kV), emitted beam lengths (500ps - 1ns) and radii (7mm - 10mm), and electromagnetic field strengths of the first subharmonic buncher (5 - 20 MV/m). The results of the simulations show that for the current setup of the ILC, a modest electron gun bias voltage ({approx}140kV) is sufficient to achieve the required bunching of the beam in the injector. Extensive simulations of parameters also involving the second subharmonic buncher should be performed in order to gain more insight into possible efficient designs for the ILC electron source injector.
Date: August 29, 2007
Creator: Lakshmanan, Manu & /Cornell U., LNS /SLAC
Object Type: Report
System: The UNT Digital Library
Development of 50 kW Fuel Processor for Stationary Fuel Cell Applications (open access)

Development of 50 kW Fuel Processor for Stationary Fuel Cell Applications

The objective of the project was to develop and test a fuel processor capable of producing high hydrogen concentration (>98%) with less than ppm quantities of carbon dioxide and carbon monoxide at lower capital cost and higher efficiency, compared to conventional natural gas reformers. It was intended that we achieve our objective by developing simple reactor/process design, and high durability CO2 absorbents, to replace pressure swing adsorption (PSA) or membrane separators. Cost analysis indicated that we would not meet DOE cost goals so the project was terminated before construction of the full scale fuel processor. The work on adsorbent development was focused on the development of calcium oxide-based reversible CO2 absorbents with various microstructures and morphologies to determine the optimum microstructure for long-term reversible CO2 absorption. The effect of powder production process variables was systematically studied including: the final target compositions, the reagents from which the final products were derived, the pore forming additives, the processing time and temperature. The sorbent materials were characterized in terms of their performance in the reversible reaction with CO2 and correlation made to their microstructure.
Date: August 29, 2007
Creator: Stevens, James F.; Krishnamurthy, Balaji; Atanassova, Paolina & Spilker, Kerry
Object Type: Report
System: The UNT Digital Library
Pulsed Laser-Based X-Ray Sources for Rapid-Cool DT Layer Characterization (open access)

Pulsed Laser-Based X-Ray Sources for Rapid-Cool DT Layer Characterization

Ignition targets for the National Ignition Facility (NIF) will contain a cryogenically cooled {approx} 75 {micro}m-thick deuterium/tritium (DT) ice layer surrounded by a {approx} 150 {micro}m-thick beryllium (Be) shell [1]. Ignition target design optimization depends sensitively on the achievable inner surface quality of the ice layer and on the pressure of the DT gas inside the ice, which is determined by the temperature of the ice. The inner ice layer surface is smoothest at temperatures just below the DT ice/liquid/gas triple point (3T), but current ignition target designs require central gas pressures of 0.3 mg/cm3, corresponding to an ice layer temperature 1.5 K below the triple point (3T-1.5). At these lower temperatures, the ice layer quality degrades due to the formation of cracks and other features.
Date: August 29, 2007
Creator: Koch, J A; Dewald, E; Izumi, N; Kozioziemski, B; Landen, O & Siders, C
Object Type: Report
System: The UNT Digital Library
Surface Treatment to Improve Corrosion Resistance in Lead-Alloy Coolants (open access)

Surface Treatment to Improve Corrosion Resistance in Lead-Alloy Coolants

One of the six proposed advanced reactor designs of the Generation IV Initiative, the Leadcooled Fast Reactor (LFR) possesses many characteristics that make it a desirable candidate for future nuclear energy production and responsible actinide management. These characteristics include favorable heat transfer, fluid dynamics, and neutronic performance compared to other candidate coolants. However, the use of a heavy liquid metal coolant presents a challenge for reactor designers in regards to reliable structural and fuel cladding materials in both a highly corrosive high temperature liquid metal and an intense radiation fieldi. Flow corrosion studies at the University of Wisconsin have examined the corrosion performance of candidate materials for application in the LFR concept as well as the viability of various surface treatments to improve the materials’ compatibility. To date this research has included several focus areas, which include the formulation of an understanding of corrosion mechanisms and the examination of the effects of chemical and mechanical surface modifications on the materials’ performance in liquid lead-bismuth by experimental testing in Los Alamos National Laboratory’s DELTA Loop, as well as comparison of experimental findings to numerical and physical models for long term corrosion prediction. This report will first review the literature and introduce …
Date: August 29, 2007
Creator: Allen, Todd R.; Sridharan, Kumar; Machut, McLean T. & Tan, Lizhen
Object Type: Report
System: The UNT Digital Library
The Power of Teamwork: Winning the 2007 Ergo Cup (open access)

The Power of Teamwork: Winning the 2007 Ergo Cup

None
Date: August 29, 2007
Creator: Naca, Christine
Object Type: Report
System: The UNT Digital Library