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Consequences of the Large-Scale Subsidence Rate on the Stably Stratified Atmospheric Boundary Layer Over the Arctic Ocean, as seen in Large-Eddy Simulations (open access)

Consequences of the Large-Scale Subsidence Rate on the Stably Stratified Atmospheric Boundary Layer Over the Arctic Ocean, as seen in Large-Eddy Simulations

The analysis of surface heat fluxes and sounding profiles from SHEBA indicated possible significant effects of subsidence on the structure of stably-stratified ABLs (Mirocha et al. 2005). In this study the influence of the large-scale subsidence rate on the stably stratified atmospheric boundary layer (ABL) over the Arctic Ocean during clear sky, winter conditions is investigated using a large-eddy simulation model. Simulations are conducted while varying the subsidence rate between 0, 0.001 and 0.002 ms{sup -1}, and the resulting quasi-equilibrium ABL structure and evolution are examined. Simulations conducted without subsidence yield ABLs that are deeper, more strongly mixed, and cool much more rapidly than were observed. The addition of a small subsidence rate significantly improves agreement between the simulations and observations regarding the ABL height, potential temperature profiles and bulk heating rates. Subsidence likewise alters the shapes of the surface-layer flux, stress and shear profiles, resulting in increased vertical transport of heat while decreasing vertical momentum transport. A brief discussion of the relevance of these results to parameterization of the stable ABL under subsiding conditions in large-scale numerical weather and climate prediction models is presented.
Date: January 19, 2006
Creator: Mirocha, J D & Kosovic, B
Object Type: Article
System: The UNT Digital Library
ToF-SIMS study of polycrystalline uranium after exposure to deuterium (open access)

ToF-SIMS study of polycrystalline uranium after exposure to deuterium

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is employed to examine specific features observed on a polycrystalline depleted uranium sample after exposure to high purity D{sub 2} gas. The ToF-SIMS investigation, being the first of its kind on uranium, investigates a site where the deuterated form of uranium hydride (UD{sub 3}) is clearly observed to have broken through the thin, air-formed oxide. Density functional theory calculations have been performed, which confirm the stability of, and also assign structural geometries to, the various uranium containing fragments observed with SIMS. An inclusion site was also investigated using ToF-SIMS, and these data suggest that the edges of such inclusions exhibit increased D ion, and hence H ion, diffusion when compared to the surrounding surface oxide. These results offer support to the previously published hypotheses that inclusion sites on uranium surfaces exhibit an increased probability to form hydride sites under H{sub 2} exposure.
Date: January 19, 2006
Creator: Morrall, P; Price, D; Nelson, A; Siekhaus, W; Nelson, E; Wu, K J et al.
Object Type: Article
System: The UNT Digital Library
Assessing the Effects of Radiation Damage on Ni-base Alloys for the Prometheus Space Reactor System (open access)

Assessing the Effects of Radiation Damage on Ni-base Alloys for the Prometheus Space Reactor System

Ni-base alloys were considered for the Prometheus space reactor pressure vessel with operational parameters of {approx}900 K for 15 years and fluences up to 160 x 10{sup 20} n/cm{sup 2} (E > 0.1 MeV). This paper reviews the effects of irradiation on the behavior of Ni-base alloys and shows that radiation-induced swelling and creep are minor considerations compared to significant embrittlement with neutron ,exposure. While the mechanism responsible for radiation-induced embrittlement is not fully understood, it is likely a combination of helium embrittlement and solute segregation that can be highly dependent on the alloy composition and exposure conditions. Transmutation calculations show that detrimental helium levels would be expected at the end of life for the inner safety rod vessel (thimble) and possibly the outer pressure vessel, primarily from high energy (E > 1 MeV) n,{alpha} reactions with {sup 58}Ni. Helium from {sup 10}B is significant only for the outer vessel due to the proximity of the outer vessel to the Be0 control elements. Recommendations for further assessments of the material behavior and methods to minimize the effects of radiation damage through alloy design are provided.
Date: January 19, 2006
Creator: Angeliu, T.
Object Type: Report
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 36, No. 596, Ed. 1 Thursday, January 19, 2006 (open access)

Greensheet (Houston, Tex.), Vol. 36, No. 596, Ed. 1 Thursday, January 19, 2006

Free weekly newspaper that includes business and classified advertising.
Date: January 19, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 36, No. 597, Ed. 1 Thursday, January 19, 2006 (open access)

Greensheet (Houston, Tex.), Vol. 36, No. 597, Ed. 1 Thursday, January 19, 2006

Free weekly newspaper that includes business and classified advertising.
Date: January 19, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Port Aransas South Jetty (Port Aransas, Tex.), Vol. 36, No. 3, Ed. 1 Thursday, January 19, 2006 (open access)

Port Aransas South Jetty (Port Aransas, Tex.), Vol. 36, No. 3, Ed. 1 Thursday, January 19, 2006

Weekly newspaper from Port Aransas, Texas on Mustang Island that includes local, state and national news along with extensive advertising.
Date: January 19, 2006
Creator: Judson, Mary Henkel
Object Type: Newspaper
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 90, No. 57, Ed. 1 Thursday, January 19, 2006 (open access)

North Texas Daily (Denton, Tex.), Vol. 90, No. 57, Ed. 1 Thursday, January 19, 2006

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state and campus news along with advertising.
Date: January 19, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History

[Student filling out a questionnaire]

Photograph of a student filling out a questionnaire at a meeting to discuss whether students should wear school uniforms in Fort Worth Texas. He is wearing a blue and black striped shirt, and there is a green purse in the background.
Date: January 19, 2006
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library

[A Speaker Looks at the Notes That Have Been Taken During a School Meeting]

Photograph of a speaker and her assistant reviewing the notes that have been taken during a school meeting in Fort Worth, Texas. The topic of discussion was whether students should wear school uniforms.
Date: January 19, 2006
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library

[Man Speaks to Parents and Students at a School Meeting in Fort Worth, Texas]

Photograph of a man speaking to parents and students at a school meeting to discuss the wearing of school uniforms in Fort Worth, Texas.
Date: January 19, 2006
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library
Mercury in the Environment: Sources and Health Risks (open access)

Mercury in the Environment: Sources and Health Risks

None
Date: January 19, 2006
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Avoiding Gridlock in the Skies: Issues and Options for Addressing Growth in Air Traffic (open access)

Avoiding Gridlock in the Skies: Issues and Options for Addressing Growth in Air Traffic

The report discusses the factors affecting airport and airspace capacity, Impact of Under-capacity on flight Operations and Impact on congestion on aviation safety.
Date: January 19, 2006
Creator: Elias, Bart
Object Type: Report
System: The UNT Digital Library
A Free Trade Area of the Americas: Major Policy Issues and Status of Negotiations (open access)

A Free Trade Area of the Americas: Major Policy Issues and Status of Negotiations

This report provides information about the Major Policy Issues and Status of Negotiations on the Free Trade Area of the Americas. The FTAA began as a commitment by 34 countries to consider a comprehensive trade agreement.
Date: January 19, 2006
Creator: Hornbeck, J. F.
Object Type: Report
System: The UNT Digital Library
Implications of the Medicare Prescription Drug Benefit for Dual Eligibles and State Medicaid Programs (open access)

Implications of the Medicare Prescription Drug Benefit for Dual Eligibles and State Medicaid Programs

This report provides information about the Implications of the Medicare Prescription Drug Benefit for Dual Eligibles and State Medicaid Programs. The report states the changes to eligibility for dual eligibles, changes to the scope of prescription coverage of the drugs.
Date: January 19, 2006
Creator: Tritz, Karen
Object Type: Report
System: The UNT Digital Library
Iraq: Summary of U.S. Casualties (open access)

Iraq: Summary of U.S. Casualties

None
Date: January 19, 2006
Creator: unknown
Object Type: Report
System: The UNT Digital Library
The Greensheet (Arlington-Grand Prairie, Tex.), Vol. 29, No. 283, Ed. 1 Thursday, January 19, 2006 (open access)

The Greensheet (Arlington-Grand Prairie, Tex.), Vol. 29, No. 283, Ed. 1 Thursday, January 19, 2006

Free weekly newspaper that includes business and classified advertising.
Date: January 19, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Fiscal Year 2006 Washington Closure Hanford Science & Technology Plan (open access)

Fiscal Year 2006 Washington Closure Hanford Science & Technology Plan

This Washington Closure Hanford science and technology (S&T) plan documents the activities associated with providing S&T support to the River Corridor Closure Project for fiscal year 2006.
Date: January 19, 2006
Creator: K.J. Kroegler, M. Truex, D.J. McBride
Object Type: Report
System: The UNT Digital Library
Water Infrastructure Project Earmarks in EPA Appropriations: Trends and Policy Implications (open access)

Water Infrastructure Project Earmarks in EPA Appropriations: Trends and Policy Implications

This report discusses appropriations for EPA water infrastructure programs, focusing on congressional earmarks in the account that funds these programs. Information on the programmatic history of EPA involvement in assisting wastewater treatment and drinking water projects is provided in two appendixes.
Date: January 19, 2006
Creator: Copeland, Claudia
Object Type: Report
System: The UNT Digital Library
Water Infrastructure Financing: History of EPA Appropriations (open access)

Water Infrastructure Financing: History of EPA Appropriations

This report summarizes, in chronological order, congressional activity to fund items in the State and Tribal Assistance Grants (STAG) account since 1987. In appropriations legislation, funding for EPA (Environmental Protection Agency) wastewater assistance is contained in the measure providing funds for the Department of the Interior, Environment, and Related Agencies.
Date: January 19, 2006
Creator: Copeland, Claudia
Object Type: Report
System: The UNT Digital Library
The Refuelable Zinc-air Battery: Alternative Techniques for Zinc and Electrolyte Regeneration (open access)

The Refuelable Zinc-air Battery: Alternative Techniques for Zinc and Electrolyte Regeneration

An investigation was conducted into alternative techniques for zinc and electrolyte regeneration and reuse in the refuelable zinc/air battery that was developed by LLNL and previously tested on a moving electric bus using cut wire. Mossy zinc was electrodeposited onto a bipolar array of inclined Ni plates with an energy consumption of 1.8 kWh/kg. Using a H{sub 2}-depolarized anode, zinc was deposited at 0.6 V (0.8 kA/m{sup 2}); the open circuit voltage was 0.45 V. Three types of fuel pellets were tested and compared with results for 0.75 mm cut wire: spheres produced in a spouted bed (UCB); coarse powder produced by gas-atomization (Noranda); and irregular pellets produced by chopping 1-mm plates of compacted zinc fines (Eagle-Picher, Inc.). All three types transported within the cell. The coarse powder fed continuously from hopper to cell, as did the compacted pellets (< 0.83 mm). Large particles (> 0.83 mm; Eagle-Picher and UCB) failed to feed from hopper into cell, being held up in the 2.5 mm wide channel connecting hopper to cell. Increasing channel width to {approx}3.5 mm should allow all three types to be used. Energy losses were determined for shorting of cells during refueling. The shorting currents between adjacent hoppers …
Date: January 19, 2006
Creator: Cooper, J F & Krueger, R
Object Type: Report
System: The UNT Digital Library

Plug-in HEVs: A Near-Term Option to Reduce Petroleum Consumption from FY05 Milestone Report

Presented to DOE management staff on September 14, 2005 at the DOE headquarters in Washington DC. Content was updated January 19, 2006 for publication. This presentation addresses plug-in hybrid electric vehicle (PHEV) market and technology issues for research and development efforts.
Date: January 19, 2006
Creator: Markel, T.; O'Keefe, M.; Simpson, A.; Gonder, J. & Brooker, A.
Object Type: Presentation
System: The UNT Digital Library
A comparison of dispersion calculations in bluff body wakes using LES and unsteady RANS (open access)

A comparison of dispersion calculations in bluff body wakes using LES and unsteady RANS

Accurate modeling of the dispersion behavior of sprays or particles is critical for a variety of problems including combustion, urban pollution or release events, and splash and spray transport around heavy vehicles. Bluff body wakes are particularly challenging since these flows are both highly separated and strongly unsteady. Attempting to model the dispersion of droplets or particles interacting with bluff body wakes is even more difficult since small differences in the flow field encountered by particles can lead to large differences in the dispersion behavior. Particles with finite inertia can exhibit additional complicating effects such as preferential concentration. In this preliminary study, we consider the dispersion of solid particles in the wake of a rectangular plane at a Reynolds number (Re) of 10000 and that of droplets in the wake of a simplified tractor-trailer geometry at Re = 2 x 10{sup 6} using both the Large Eddy Simulation (LES) and Unsteady Reynolds-Averaged Navier-Stokes (URANS) turbulence modeling approaches. The calculations were performed using identical meshes for both the LES and URANS models. Particle stresses are not backcoupled to the carrier fluid velocity solution. In the case of the rectangular plane wake, the LES calculation predicts a finer-scale and more persistent wake …
Date: January 19, 2006
Creator: Paschkewitz, J S
Object Type: Report
System: The UNT Digital Library
GLASS FABRICATION AND PRODUCT CONSISTENCY TESTING OF LANTHANIDE BOROSILICATE FRIT B COMPOSITION FOR PLUTONIUM DISPOSITION (open access)

GLASS FABRICATION AND PRODUCT CONSISTENCY TESTING OF LANTHANIDE BOROSILICATE FRIT B COMPOSITION FOR PLUTONIUM DISPOSITION

The Department of Energy Office of Environmental Management (DOE/EM) plans to conduct the Plutonium Disposition Project at the Savannah River Site (SRS) to disposition excess weapons-usable plutonium. A plutonium glass waste form is a leading candidate for immobilization of the plutonium for subsequent disposition in a geologic repository. A reference glass composition (Lanthanide Borosilicate (LaBS) Frit B) was developed during the Plutonium Immobilization Program (PIP) to immobilize plutonium. A limited amount of performance testing was performed on this baseline composition before efforts to further pursue Pu disposition via a glass waste form ceased. Therefore, the objectives of this present task were to fabricate plutonium loaded LaBS Frit B glass and perform additional testing to provide near-term data that will increase confidence that LaBS glass product is suitable for disposal in the Yucca Mountain Repository. Specifically, testing was conducted in an effort to provide data to Yucca Mountain Project (YMP) personnel for use in performance assessment calculations. Plutonium containing LaBS glass with the Frit B composition with a 9.5 wt% PuO{sub 2} loading was prepared for testing. Glass was prepared to support Product Consistency Testing (PCT) at Savannah River National Laboratory (SRNL) and for additional performance testing at Argonne National Laboratory …
Date: January 19, 2006
Creator: Marra, J
Object Type: Report
System: The UNT Digital Library
Development of an Alternative Glass Formulation for Vitrification of Excess Plutonium (open access)

Development of an Alternative Glass Formulation for Vitrification of Excess Plutonium

None
Date: January 19, 2006
Creator: MARRA, JAMES
Object Type: Report
System: The UNT Digital Library