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Fermi Large Area Telescope Observations of the Cosmic-Ray Induced (open access)

Fermi Large Area Telescope Observations of the Cosmic-Ray Induced

We report on measurements of the cosmic-ray induced {gamma}-ray emission of Earth's atmosphere by the Large Area Telescope onboard the Fermi Gamma-ray Space Telescope. The LAT has observed the Earth during its commissioning phase and with a dedicated Earth-limb following observation in September 2008. These measurements yielded {approx} 6.4 x 10{sup 6} photons with energies > 100 MeV and {approx} 250 hours total livetime for the highest quality data selection. This allows the study of the spatial and spectral distributions of these photons with unprecedented detail. The spectrum of the emission - often referred to as Earth albedo gamma-ray emission - has a power-law shape up to 500 GeV with spectral index {Lambda} = 2.79 {+-} 0.06.
Date: February 29, 2012
Creator: Abdo, A. A.
Object Type: Report
System: The UNT Digital Library
The European Union: Questions and Answers (open access)

The European Union: Questions and Answers

This report serves as a primer on the EU and provides a brief description of U.S.-EU relations. It also discusses about how EU works, how EU is governed and Eurozone crisis.
Date: February 29, 2012
Creator: Archick, Kristin
Object Type: Report
System: The UNT Digital Library
FINAL REPORT –INDEPENDENT VERIFICATION SURVEY SUMMARY AND RESULTS FOR THE ARGONNE NATIONAL LABORATORY BUILDING 330 PROJECT FOOTPRINT, ARGONNE, ILLINOIS (open access)

FINAL REPORT –INDEPENDENT VERIFICATION SURVEY SUMMARY AND RESULTS FOR THE ARGONNE NATIONAL LABORATORY BUILDING 330 PROJECT FOOTPRINT, ARGONNE, ILLINOIS

ORISE conducted onsite verification activities of the Building 330 project footprint during the period of June 6 through June 7, 2011. The verification activities included technical reviews of project documents, visual inspections, radiation surface scans, and sampling and analysis. The draft verification report was issued in July 2011 with findings and recommendations. The contractor performed additional evaluations and remediation.
Date: February 29, 2012
Creator: BAILEY, ERIKA N.
Object Type: Report
System: The UNT Digital Library
Changes to the Government Performance and Results Act (GPRA): Overview of the New Framework of Products and Processes (open access)

Changes to the Government Performance and Results Act (GPRA): Overview of the New Framework of Products and Processes

This report is categorized into four categories: (I) Background: Congress and Performance, (II) GPRAMA's Products and Processes, (III) Viewing the Products and Processes Together and (IV) Potential Implications and Issues for Congress.
Date: February 29, 2012
Creator: Brass, Clinton T.
Object Type: Report
System: The UNT Digital Library
ToHajiilee Economic Development, Inc.(TEDI) Feasibility Study for Utility-Scale Solar (open access)

ToHajiilee Economic Development, Inc.(TEDI) Feasibility Study for Utility-Scale Solar

To™Hajiilee Economic Development, Inc. (TEDI) is the economic development entity representing the ToHajiilee Chapter of the Navajo Nation, also known as the CaÃoncito Band of Navajo (CBN). Using DOE funding, TEDI assembled a team of qualified advisors to conduct a feasibility study for a utility-scale 30 MW Photovoltaic (PV) solar power generation facility on TEDI trust lands. The goal for this project has been to gather information and practical business commitments to successfully complete the feasibility analysis. The TEDI approach was to successively make informed decisions to select an appropriate technology best suited to the site, determine environmental viability of the site, secure options for the sale of generated power, determine practicality of transmission and interconnection of power to the local grid, and secure preliminary commitments on project financing. The feasibility study has been completed and provides TEDI with a practical understanding of its business options in moving forward with developing a solar project on CBN tribal lands. Funding from DOE has allowed TEDI and its team of professional advisors to carefully select technology and business partners and build a business model to develop this utility-scale solar project. As a result of the positive feasibility findings, TEDI is moving forward …
Date: February 29, 2012
Creator: Burpo, Rob
Object Type: Report
System: The UNT Digital Library
The Altus Times (Altus, Okla.), Vol. 112, No. 231, Ed. 1 Wednesday, February 29, 2012 (open access)

The Altus Times (Altus, Okla.), Vol. 112, No. 231, Ed. 1 Wednesday, February 29, 2012

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: February 29, 2012
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Mass Distribution and Assembly of the Milky Way from the Properties of the Magellanic Clouds (open access)

The Mass Distribution and Assembly of the Milky Way from the Properties of the Magellanic Clouds

We present a new measurement of the mass of the Milky Way (MW) based on observed properties of its largest satellite galaxies, the Magellanic Clouds (MCs), and an assumed prior of a {Lambda}CDM universe. The large, high-resolution Bolshoi cosmological simulation of this universe provides a means to statistically sample the dynamical properties of bright satellite galaxies in a large population of dark matter halos. The observed properties of the MCs, including their circular velocity, distance from the center of the MW, and velocity within the MW halo, are used to evaluate the likelihood that a given halo would have each or all of these properties; the posterior probability distribution function (PDF) for any property of the MW system can thus be constructed. This method provides a constraint on the MW virial mass, 1.2{sup +0.7} - {sub 0.4}(stat.){sup +0.3} - {sub 0.3}(sys.) x 10{sup 12} M {circle_dot} (68% confidence), which is consistent with recent determinations that involve very different assumptions. In addition, we calculate the posterior PDF for the density profile of the MW and its satellite accretion history. Although typical satellites of 10{sup 12} M {circle_dot} halos are accreted over a wide range of epochs over the last 10 Gyr, …
Date: February 29, 2012
Creator: Busha, Michael T.; Marshall, Philip J.; Wechsler, Risa H.; Klypin, Anatoly & Primack, Joel
Object Type: Article
System: The UNT Digital Library
Fusion Simulation Program (open access)

Fusion Simulation Program

Under this project, General Atomics (GA) was tasked to develop the experimental validation plans for two high priority ISAs, Boundary and Pedestal and Whole Device Modeling in collaboration with the theory, simulation and experimental communities. The following sections have been incorporated into the final FSP Program Plan (www.pppl.gov/fsp), which was delivered to the US Department of Energy (DOE). Additional deliverables by GA include guidance for validation, development of metrics to evaluate success and procedures for collaboration with experiments. These are also part of the final report.
Date: February 29, 2012
Creator: Chan), Project Staff (V.S.
Object Type: Report
System: The UNT Digital Library
Afghanistan Casualties: Military Forces and Civilians (open access)

Afghanistan Casualties: Military Forces and Civilians

This report collects statistics from a variety of sources on casualties sustained during Operation Enduring Freedom (OEF), which began on October 7, 2001, and is ongoing. OEF actions take place primarily in Afghanistan; however, OEF casualties also include American casualties in Pakistan, Uzbekistan, Guantanamo Bay (Cuba), Djibouti, Eritrea, Ethiopia, Jordan, Kenya, Kyrgyzstan, the Philippines, Seychelles, Sudan, Tajikistan, Turkey, and Yemen.
Date: February 29, 2012
Creator: Chesser, Susan G.
Object Type: Report
System: The UNT Digital Library
EVALUATION OF ALTERNATE STAINLESS STEEL SURFACE TREATMENTS FOR MASS SPECTROSCOPY AND OTHER TRITIUM SYSTEMS (open access)

EVALUATION OF ALTERNATE STAINLESS STEEL SURFACE TREATMENTS FOR MASS SPECTROSCOPY AND OTHER TRITIUM SYSTEMS

There are specific components in the SRS Tritium Facilities that are required to introduce as few chemical impurities (such as protium and methane) as possible into the process gas. Two such components are the inlet systems for the mass spectroscopy facilities and hydrogen isotope mix standard containers. Two vendors now passivate stainless steel components for these systems, and both are relatively small businesses whose future viability can be questioned, which creates the need for new sources. Stainless steel containers were designed to evaluate alternate surface treatment vendors for tritium storage and handling for these high purity tritium systems. Five vendors applied their own 'best' surface treatments to two containers each - one was a current vendor, another was a chemical vapor deposited silicon coating, and the other three were electropolishing and chemical cleaning vendors. Pure tritium gas was introduced into all ten containers and the composition was monitored over time. The only observed impurities in the gas were some HT, less CT{sub 4}, and very small amounts of T{sub 2}O in all cases. The currently used vendor treated containers contained the least impurities. The chemical vapor deposited silicon treatment resulted in the highest impurity levels. Sampling one set of containers …
Date: February 29, 2012
Creator: Clark, E.; Mauldin, C. & Neikirk, K.
Object Type: Report
System: The UNT Digital Library

Master Recital: 2012-02-29 - Ilia De la Rosa, Cello

Access: Use of this item is restricted to the UNT Community
A masters recital performed at the UNT College of Music Voertman Hall.
Date: February 29, 2012
Creator: De la Rosa, Ilia
Object Type: Sound
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Wednesday, February 29, 2012 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Wednesday, February 29, 2012

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: February 29, 2012
Creator: DeSilver, Debi
Object Type: Newspaper
System: The Gateway to Oklahoma History
EVOLUTION OF CHEMICAL CONDITIONS AND ESTIMATED PLUTONIUM SOLUBILITY IN THE RESIDUAL WASTE LAYER DURING POST-CLOSURE AGING OF TANK 18 (open access)

EVOLUTION OF CHEMICAL CONDITIONS AND ESTIMATED PLUTONIUM SOLUBILITY IN THE RESIDUAL WASTE LAYER DURING POST-CLOSURE AGING OF TANK 18

This document updates the Eh-pH transitions from grout aging simulations and the plutonium waste release model of Denham (2007, Rev. 1) based on new data. New thermodynamic data for cementitious minerals are used for the grout simulations. Newer thermodynamic data, recommended by plutonium experts (Plutonium Solubility Peer Review Report, LA-UR-12-00079), are used to estimate solubilities of plutonium at various pore water compositions expected during grout aging. In addition, a new grout formula is used in the grout aging simulations and apparent solubilities of coprecipitated plutonium are estimated using data from analysis of Tank 18 residual waste. The conceptual model of waste release and the grout aging simulations are done in a manner similar to that of Denham (2007, Rev. 1). It is assumed that the pore fluid composition passing from the tank grout into the residual waste layer controls the solubility, and hence the waste release concentration of plutonium. Pore volumes of infiltrating fluid of an assumed composition are reacted with a hypothetical grout block using The Geochemist's Workbench{reg_sign} and changes in pore fluid chemistry correspond to the number of pore fluid volumes reacted. As in the earlier document, this results in three states of grout pore fluid composition throughout …
Date: February 29, 2012
Creator: Denham, M.
Object Type: Report
System: The UNT Digital Library
High-Resolution Methods for Phase Space Problems in Complex Geometries (open access)

High-Resolution Methods for Phase Space Problems in Complex Geometries

None
Date: February 29, 2012
Creator: Dorr, M. R.; Colella, P.; Hittinger, J. A.; Martin, D. F. & McCorquodale, P. W.
Object Type: Article
System: The UNT Digital Library
Fundamental Studies and Development of III-N Visible LEDs for High-Power Solid-State Lighting Applications (open access)

Fundamental Studies and Development of III-N Visible LEDs for High-Power Solid-State Lighting Applications

The goal of this program is to understand in a fundamental way the impact of strain, defects, polarization, and Stokes loss in relation to unique device structures upon the internal quantum efficiency (IQE) and efficiency droop (ED) of III-nitride (III-N) light-emitting diodes (LEDs) and to employ this understanding in the design and growth of high-efficiency LEDs capable of highly-reliable, high-current, high-power operation. This knowledge will be the basis for our advanced device epitaxial designs that lead to improved device performance. The primary approach we will employ is to exploit new scientific and engineering knowledge generated through the application of a set of unique advanced growth and characterization tools to develop new concepts in strain-, polarization-, and carrier dynamics-engineered and low-defect materials and device designs having reduced dislocations and improved carrier collection followed by efficient photon generation. We studied the effects of crystalline defect, polarizations, hole transport, electron-spillover, electron blocking layer, underlying layer below the multiplequantum- well active region, and developed high-efficiency and efficiency-droop-mitigated blue LEDs with a new LED epitaxial structures. We believe new LEDs developed in this program will make a breakthrough in the development of high-efficiency high-power visible III-N LEDs from violet to green spectral region.
Date: February 29, 2012
Creator: Dupuis, Russell
Object Type: Report
System: The UNT Digital Library
Initial Decision and Risk Analysis (open access)

Initial Decision and Risk Analysis

Decision and Risk Analysis capabilities will be developed for industry consideration and possible adoption within Year 1. These tools will provide a methodology for merging qualitative ranking of technology maturity and acknowledged risk contributors with quantitative metrics that drive investment decision processes. Methods and tools will be initially introduced as applications to the A650.1 case study, but modular spreadsheets and analysis routines will be offered to industry collaborators as soon as possible to stimulate user feedback and co-development opportunities.
Date: February 29, 2012
Creator: Engel, David W.
Object Type: Report
System: The UNT Digital Library
[Email from Jack and George to Dallas Way members, February 29, 2012] (open access)

[Email from Jack and George to Dallas Way members, February 29, 2012]

Email from Jack and George to Dallas Way members discussing the upcoming Power Lunch hosted by the Dallas Way.
Date: February 29, 2012
Creator: Evans, Jack & Harris, George E.
Object Type: Letter
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 97, No. 119, Ed. 1 Wednesday, February 29, 2012 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 97, No. 119, Ed. 1 Wednesday, February 29, 2012

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: February 29, 2012
Creator: Gibbs, Angenene
Object Type: Newspaper
System: The Gateway to Oklahoma History
Cherokeean Herald (Rusk, Tex.), Vol. 163, No. 1, Ed. 1 Wednesday, February 29, 2012 (open access)

Cherokeean Herald (Rusk, Tex.), Vol. 163, No. 1, Ed. 1 Wednesday, February 29, 2012

Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.
Date: February 29, 2012
Creator: Gonzalez, Terrie
Object Type: Newspaper
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 99, No. 26, Ed. 1 Wednesday, February 29, 2012 (open access)

North Texas Daily (Denton, Tex.), Vol. 99, No. 26, Ed. 1 Wednesday, February 29, 2012

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state, and campus news along with advertising.
Date: February 29, 2012
Creator: Gorman, Sean
Object Type: Newspaper
System: The Portal to Texas History
Prototyping of the ILC Baseline Positron Target (open access)

Prototyping of the ILC Baseline Positron Target

The ILC positron system uses novel helical undulators to create a powerful photon beam from the main electron beam. This beam is passed through a titanium target to convert it into electron-positron pairs. The target is constructed as a 1 m diameter wheel spinning at 2000 RPM to smear the 1 ms ILC pulse train over 10 cm. A pulsed flux concentrating magnet is used to increase the positron capture efficiency. It is cooled to liquid nitrogen temperatures to maximize the flatness of the magnetic field over the 1 ms ILC pulse train. We report on prototyping effort on this system.
Date: February 29, 2012
Creator: Gronberg, J.; Brooksby, C.; Piggott, T.; Abbott, R.; Javedani, J. & Cook, E.
Object Type: Article
System: The UNT Digital Library
ADVANCED OXIDATION: OXALATE DECOMPOSITION TESTING WITH OZONE (open access)

ADVANCED OXIDATION: OXALATE DECOMPOSITION TESTING WITH OZONE

At the Savannah River Site (SRS), oxalic acid is currently considered the preferred agent for chemically cleaning the large underground Liquid Radioactive Waste Tanks. It is applied only in the final stages of emptying a tank when generally less than 5,000 kg of waste solids remain, and slurrying based removal methods are no-longer effective. The use of oxalic acid is preferred because of its combined dissolution and chelating properties, as well as the fact that corrosion to the carbon steel tank walls can be controlled. Although oxalic acid is the preferred agent, there are significant potential downstream impacts. Impacts include: (1) Degraded evaporator operation; (2) Resultant oxalate precipitates taking away critically needed operating volume; and (3) Eventual creation of significant volumes of additional feed to salt processing. As an alternative to dealing with the downstream impacts, oxalate decomposition using variations of ozone based Advanced Oxidation Process (AOP) were investigated. In general AOPs use ozone or peroxide and a catalyst to create hydroxyl radicals. Hydroxyl radicals have among the highest oxidation potentials, and are commonly used to decompose organics. Although oxalate is considered among the most difficult organic to decompose, the ability of hydroxyl radicals to decompose oxalate is considered to …
Date: February 29, 2012
Creator: Ketusky, E. & Subramanian, K.
Object Type: Article
System: The UNT Digital Library
DYNAMIC MECHANICAL ANALYSIS CHARACTERIZATION OF GLOVEBOX GLOVES (open access)

DYNAMIC MECHANICAL ANALYSIS CHARACTERIZATION OF GLOVEBOX GLOVES

As part of the characterization of various glovebox glove material from four vendors, the permeability of gas through each type as a function of temperature was determined and a discontinuity in the permeability with temperature was revealed. A series of tests to determine the viscoelastic properties of the glove materials as a function of temperature using Dynamic Mechanical Analysis (DMA) was initiated. The glass transition temperature and the elastic and viscoelastic properties as a function of temperature up to maximum use temperature were determined for each glove material. The glass transition temperatures of the gloves were -60 C for butyl, -30 C for polyurethane, -16 C Hypalon{reg_sign}, - 16 C for Viton{reg_sign}, and -24 C for polyurethane-Hypalon{reg_sign}. The glass transition was too complex for the butyl-Hypalon{reg_sign} and butyl-Viton{reg_sign} composite gloves to be characterized by a single glass transition temperature. All of the glass transition temperatures exceed the vendor projected use temperatures.
Date: February 29, 2012
Creator: Korinko, P.
Object Type: Report
System: The UNT Digital Library
EVALUATION OF GLOVEBOX GLOVES FOR EFFECTIVE PERMEATION CONTROL (open access)

EVALUATION OF GLOVEBOX GLOVES FOR EFFECTIVE PERMEATION CONTROL

A research and development task was undertaken to determine the permeabilities of hydrogen and dry air through different polymeric glove materials that are used to maintain the integrity of glovebox secondary containment. Fifteen different glove samples were obtained from four different manufacturers and samples cut from these gloves were tested. The gloves included baseline butyl rubber, Viton{reg_sign}, Dupont{reg_sign} Hypalon{reg_sign}, polyurethane, as well as composite gloves. The testing indicated that all of the vendor's butyl rubber gloves and the Jung Viton{reg_sign} gloves performed comparably in both gases.
Date: February 29, 2012
Creator: Korinko, P.
Object Type: Report
System: The UNT Digital Library