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Maritime Security: Progress Made, but Further Actions Needed to Secure the Maritime Energy Supply (open access)

Maritime Security: Progress Made, but Further Actions Needed to Secure the Maritime Energy Supply

Testimony issued by the Government Accountability Office with an abstract that begins "The nation's economy and security are heavily dependent on oil, natural gas, and other energy commodities. Al-Qa'ida and other groups with malevolent intent have targeted energy tankers and offshore energy infrastructure because of their importance to the nation's economy and national security. The U.S. Coast Guard--a component of the Department of Homeland Security (DHS)--is the lead federal agency for maritime security, including the security of energy tankers and offshore energy infrastructure. The Federal Bureau of Investigation (FBI) also has responsibilities for preventing and responding to terrorist incidents. This testimony discusses the extent to which (1) the Coast Guard and the FBI have taken actions to address GAO's prior recommendations to prevent and respond to a terrorist incident involving energy tankers and (2) the Coast Guard has taken actions to assess the security risks to offshore energy infrastructure and related challenges. This testimony is based on products issued from December 2007 through March 2011 and recently completed work on the Coast Guard's actions to assess security risks. GAO reviewed documents from the Coast Guard's risk model and relevant laws, regulations, policies, and procedures; and interviewed Coast Guard officials."
Date: August 24, 2011
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
The Greensheet (Houston, Tex.), Vol. 42, No. 354, Ed. 1 Wednesday, August 24, 2011 (open access)

The Greensheet (Houston, Tex.), Vol. 42, No. 354, Ed. 1 Wednesday, August 24, 2011

Free weekly newspaper that includes business and classified advertising.
Date: August 24, 2011
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Russian Military Reform and Defense Policy (open access)

Russian Military Reform and Defense Policy

This report looks at the Russia's revamping of the armed forces that it inherited from the Soviet Union. It discusses the revamping process as well as the new armed forces' relationship with the U.S.
Date: August 24, 2011
Creator: Nichol, Jim
Object Type: Report
System: The UNT Digital Library
Cuba: U.S. Restrictions on Travel and Remittances (open access)

Cuba: U.S. Restrictions on Travel and Remittances

This report discusses details of policy changes regarding travel to Cuba, which have been a key and often contentious component in U.S. efforts to isolate Cuba's communist government since the early 1960s. In January 2011, the Obama Administration announced policy changes further easing restrictions on travel and remittances. In the first session of the 112th Congress, there were several attempts aimed at rolling back the Obama Administration's actions easing restrictions on travel and remittances. Several initiatives were also introduced that would further ease or lift such restrictions altogether.
Date: August 24, 2011
Creator: Sullivan, Mark P.
Object Type: Report
System: The UNT Digital Library
Cherokeean Herald (Rusk, Tex.), Vol. 162, No. 26, Ed. 1 Wednesday, August 24, 2011 (open access)

Cherokeean Herald (Rusk, Tex.), Vol. 162, No. 26, Ed. 1 Wednesday, August 24, 2011

Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.
Date: August 24, 2011
Creator: Whitehead, Marie
Object Type: Newspaper
System: The Portal to Texas History
TREATMENT TANK CORROSION STUDIES FOR THE ENHANCED CHEMICAL CLEANING PROCESS (open access)

TREATMENT TANK CORROSION STUDIES FOR THE ENHANCED CHEMICAL CLEANING PROCESS

Radioactive waste is stored in high level waste tanks on the Savannah River Site (SRS). Savannah River Remediation (SRR) is aggressively seeking to close the non-compliant Type I and II waste tanks. The removal of sludge (i.e., metal oxide) heels from the tank is the final stage in the waste removal process. The Enhanced Chemical Cleaning (ECC) process is being developed and investigated by SRR to aid in Savannah River Site (SRS) High-Level Waste (HLW) as an option for sludge heel removal. Corrosion rate data for carbon steel exposed to the ECC treatment tank environment was obtained to evaluate the degree of corrosion that occurs. These tests were also designed to determine the effect of various environmental variables such as temperature, agitation and sludge slurry type on the corrosion behavior of carbon steel. Coupon tests were performed to estimate the corrosion rate during the ECC process, as well as determine any susceptibility to localized corrosion. Electrochemical studies were performed to develop a better understanding of the corrosion mechanism. The tests were performed in 1 wt.% and 2.5 wt.% oxalic acid with HM and PUREX sludge simulants. The following results and conclusions were made based on this testing: (1) In 1 …
Date: August 24, 2011
Creator: Wiersma, B.
Object Type: Report
System: The UNT Digital Library
Emergence of the Persistent Spin Helix in Semiconductor Quantum Wells (open access)

Emergence of the Persistent Spin Helix in Semiconductor Quantum Wells

According to Noether's theorem, for every symmetry in nature there is a corresponding conservation law. For example, invariance with respect to spatial translation corresponds to conservation of momentum. In another well-known example, invariance with respect to rotation of the electron's spin, or SU(2) symmetry, leads to conservation of spin polarization. For electrons in a solid, this symmetry is ordinarily broken by spin-orbit (SO) coupling, allowing spin angular momentum to flow to orbital angular momentum. However, it has recently been predicted that SU(2) can be recovered in a two-dimensional electron gas (2DEG), despite the presence of SO coupling. The corresponding conserved quantities include the amplitude and phase of a helical spin density wave termed the 'persistent spin helix' (PSH). SU(2) is restored, in principle, when the strength of two dominant SO interactions, the Rashba ({alpha}) and linear Dresselhaus ({beta}{sub 1}), are equal. This symmetry is predicted to be robust against all forms of spin-independent scattering, including electron-electron interactions, but is broken by the cubic Dresselhaus term ({beta}{sub 3}) and spin-dependent scattering. When these terms are negligible, the distance over which spin information can propagate is predicted to diverge as {alpha} {yields} {beta}{sub 1}. Here we observe experimentally the emergence of the …
Date: August 24, 2011
Creator: Koralek, Jake; Weber, Chris; Orenstein, Joe; Bernevig, Andrei; Zhang, Shoucheng; Mack, Shawn et al.
Object Type: Article
System: The UNT Digital Library
Polar Kerr Effect Measurements of YBa_2Cu_3O_6+x: Evidence for Broken Symmetry Near the Pseudogap Temperature (open access)

Polar Kerr Effect Measurements of YBa_2Cu_3O_6+x: Evidence for Broken Symmetry Near the Pseudogap Temperature

Polar Kerr effect in the high-Tc superconductor YBa{sub 2}Cu{sub 3}O{sub 6+x} was measured at zero magnetic field with high precision using a cyogenic Sagnac fiber interferometer. We observed non-zero Kerr rotations of order {approx} 1 {micro}rad appearing near the pseudogap temperature T*, and marking what appears to be a true phase transition. Anomalous magnetic behavior in magnetic-field training of the effect suggests that time reversal symmetry is already broken above room temperature.
Date: August 24, 2011
Creator: Xia, Jing
Object Type: Article
System: The UNT Digital Library
In Situ X-Ray Probing Reveals Fingerprints of Surface Platinum Oxide (open access)

In Situ X-Ray Probing Reveals Fingerprints of Surface Platinum Oxide

In situ x-ray absorption spectroscopy (XAS) at the Pt L{sub 3} edge is a useful probe for Pt-O interactions at polymer electrolyte membrane fuel cell (PEMFC) cathodes. We show that XAS using the high energy resolution fluorescence detection (HERFD) mode, applied to a well-defined monolayer Pt/Rh(111) sample where the bulk penetrating hard x-rays probe only surface Pt atoms, provides a unique sensitivity to structure and chemical bonding at the Pt-electrolyte interface. Ab initio multiple-scattering calculations using the FEFF8 code and complementary extended x-ray absorption fine structure (EXAFS) results indicate that the commonly observed large increase of the white-line at high electrochemical potentials on PEMFC cathodes originates from platinum oxide formation, whereas previously proposed chemisorbed oxygen-containing species merely give rise to subtle spectral changes.
Date: August 24, 2011
Creator: Friebel, Daniel
Object Type: Article
System: The UNT Digital Library
Precision Determination of Atmospheric Extinction at Optical and Near IR Wavelengths (open access)

Precision Determination of Atmospheric Extinction at Optical and Near IR Wavelengths

The science goals for future ground-based all-sky surveys, such as the Dark Energy Survey, PanSTARRS, and the Large Synoptic Survey Telescope, require calibration of broadband photometry that is stable in time and uniform over the sky to precisions of a per cent or better, and absolute calibration of color measurements that are similarly accurate. This performance will need to be achieved with measurements made from multiple images taken over the course of many years, and these surveys will observe in less than ideal conditions. This paper describes a technique to implement a new strategy to directly measure variations of atmospheric transmittance at optical wavelengths and application of these measurements to calibration of ground-based observations. This strategy makes use of measurements of the spectra of a small catalog of bright 'probe' stars as they progress across the sky and back-light the atmosphere. The signatures of optical absorption by different atmospheric constituents are recognized in these spectra by their characteristic dependences on wavelength and airmass. State-of-the-art models of atmospheric radiation transport and modern codes are used to accurately compute atmospheric extinction over a wide range of observing conditions. We present results of an observing campaign that demonstrate that correction for extinction due …
Date: August 24, 2011
Creator: Burke, David L.; Axelrod, T.; Blondin, Stephane; Claver, Chuck; Ivezic, Zeljko; Jones, Lynne et al.
Object Type: Article
System: The UNT Digital Library
Observation of Magnetic Resonances in Electron Clouds in a Positron Storage Ring (open access)

Observation of Magnetic Resonances in Electron Clouds in a Positron Storage Ring

The first experimental observation of magnetic resonances in electron clouds is reported. The resonance was observed as a modulation in cloud intensity for uncoated as well as TiN-coated aluminum surfaces in the positron storage ring of the PEP-II collider at SLAC. Electron clouds frequently arise in accelerators of positively charged particles, and severely impact the machines performance. The TiN coating was found to be an effective remedy, reducing the cloud intensity by three orders of magnitude.
Date: August 24, 2011
Creator: Pivi, M. T. F.; Ng, J. S. T.; Cooper, F.; Kharakh, D.; King, F.; Kirby, R. E. et al.
Object Type: Article
System: The UNT Digital Library
UNDERSTANDING THE EFFECTS OF COMPRESSION AND CONSTRAINTS ON WATER UPTAKE OF FUEL-CELL MEMBRANES (open access)

UNDERSTANDING THE EFFECTS OF COMPRESSION AND CONSTRAINTS ON WATER UPTAKE OF FUEL-CELL MEMBRANES

Accurate characterization of polymer-electrolyte fuel cells (PEFCs) requires understanding the impact of mechanical and electrochemical loads on cell components. An essential aspect of this relationship is the effect of compression on the polymer membrane?s water-uptake behavior and transport properties. However, there is limited information on the impact of physical constraints on membrane properties. In this paper, we investigate both theoretically and experimentally how the water uptake of Nafion membrane changes under external compression loads. The swelling of a compressed membrane is modeled by modifying the swelling pressure in the polymer backbone which relies on the changes in the microscopic volume of the polymer. The model successfully predicts the water content of the compressed membrane measured through in-situ swelling-compression tests and neutron imaging. The results show that external mechanical loads could reduce the water content and conductivity of the membrane, especially at lower temperatures, higher humidities, and in liquid water. The modeling framework and experimental data provide valuable insight for the swelling and conductivity of constrained and compressed membranes, which are of interest in electrochemical devices such as batteries and fuel cells.
Date: August 24, 2011
Creator: Kusoglu, Ahmet; Kienitz, Briian & Weber, Adam
Object Type: Article
System: The UNT Digital Library
The Role of Low-Angle Extensional Tectonics, Flat Fracture Domains, and Gravity Slides in Hydrothermal and EGS Resources of the Western United States (open access)

The Role of Low-Angle Extensional Tectonics, Flat Fracture Domains, and Gravity Slides in Hydrothermal and EGS Resources of the Western United States

The Steamboat Springs geothermal system provides the most dramatic example of subhorizontal thermal-fluid aquifers in crystalline rock in the Basin and Range, but this is by no means an isolated case. Similar but more diffuse subhorizontal permeability has been reported at Roosevelt Hot Springs and Cove-Fort Sulphurdale, Utah; and a km-scale gravity-slide block channels injectate at Dixie Valley, Nevada. During the course of this phase of the project 2543 reports including text, figures and large format enclosures, 1428 maps, and 698 well logs were scanned. The information is stored in a Microsoft Access Database on the Geothermal Server. Detailed geologic cross sections of the Desert Peak geothermal field were developed to identify the structural controls on the geothermal system and locate possible fluid flow paths. The results of this work were published by Lutz and others (2009, Appendix 1) in the Stanford Reservoir Engineering Conference Proceedings.
Date: August 24, 2011
Creator: Moore, Joseph
Object Type: Report
System: The UNT Digital Library
Yoakum Herald-Times (Yoakum, Tex.), Vol. 119, No. 34, Ed. 1 Wednesday, August 24, 2011 (open access)

Yoakum Herald-Times (Yoakum, Tex.), Vol. 119, No. 34, Ed. 1 Wednesday, August 24, 2011

Weekly newspaper from Yoakum, Texas that includes local, state, and national news along with advertising.
Date: August 24, 2011
Creator: McCracken, Michael S.
Object Type: Newspaper
System: The Portal to Texas History
Jackson County Herald-Tribune (Edna, Tex.), Vol. 104, No. 39, Ed. 1 Wednesday, August 24, 2011 (open access)

Jackson County Herald-Tribune (Edna, Tex.), Vol. 104, No. 39, Ed. 1 Wednesday, August 24, 2011

Weekly newspaper from Edna, Texas that includes local, state, and national news along with advertising.
Date: August 24, 2011
Creator: Lundstrom, Chris
Object Type: Newspaper
System: The Portal to Texas History
The Baytown Sun (Baytown, Tex.), Vol. 91, No. 166, Ed. 1 Wednesday, August 24, 2011 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 91, No. 166, Ed. 1 Wednesday, August 24, 2011

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: August 24, 2011
Creator: Gray, Janie
Object Type: Newspaper
System: The Portal to Texas History
The Cuero Record (Cuero, Tex.), Vol. 117, No. 34, Ed. 1 Wednesday, August 24, 2011 (open access)

The Cuero Record (Cuero, Tex.), Vol. 117, No. 34, Ed. 1 Wednesday, August 24, 2011

Weekly newspaper from Cuero, Texas that includes local, state and national news along with advertising.
Date: August 24, 2011
Creator: Rea, Glenn
Object Type: Newspaper
System: The Portal to Texas History
Energy Development and Water Use: Impacts of Potential Oil Shale Development on Water Resources (open access)

Energy Development and Water Use: Impacts of Potential Oil Shale Development on Water Resources

Testimony issued by the Government Accountability Office with an abstract that begins "Oil shale deposits in Colorado, Utah, and Wyoming are estimated to contain up to 3 trillion barrels of oil--or an amount equal to the world's proven oil reserves. About 72 percent of this oil shale is located beneath federal lands managed by the Department of the Interior's Bureau of Land Management, making the federal government a key player in its potential development. Extracting this oil is expected to require substantial amounts of water and could impact groundwater and surface water. GAO's testimony is based on its October 2010 report on the impacts of oil shale development (GAO-11-35). This testimony summarizes (1) what is known about the potential impacts of oil shale development on surface water and groundwater, (2) what is known about the amount of water that may be needed for commercial oil shale development, (3) the extent to which water will likely be available for such development and its source, and (4) federal research efforts to address impacts to water resources from commercial oil shale development. For its October 2010 report, GAO reviewed studies and interviewed water experts, officials from federal and state agencies, and oil shale …
Date: August 24, 2011
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Sweetwater Reporter (Sweetwater, Tex.), Vol. 113, No. 240, Ed. 1 Wednesday, August 24, 2011 (open access)

Sweetwater Reporter (Sweetwater, Tex.), Vol. 113, No. 240, Ed. 1 Wednesday, August 24, 2011

Daily newspaper from Sweetwater, Texas that includes local, state, and national news along with advertising.
Date: August 24, 2011
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Noncitizen Eligibility for Federal Public Assistance: Policy Overview and Trends (open access)

Noncitizen Eligibility for Federal Public Assistance: Policy Overview and Trends

None
Date: August 24, 2011
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Higher Education Tax Benefits: Brief Overview and Budgetary Effects (open access)

Higher Education Tax Benefits: Brief Overview and Budgetary Effects

This report provides a brief overview of the higher education tax benefits that are currently available to students and their families. The report contrasts higher education tax benefits with traditional aid, presents a brief history of higher education tax policy over the past 60 years, summarizes key features of the available tax benefits, and provides JCT estimates of revenue losses resulting from individual tax provisions.
Date: August 24, 2011
Creator: Crandall-Hollick, Margot L. & Keightley, Mark P.
Object Type: Report
System: The UNT Digital Library
The Federal Networking and Information Technology Research and Development Program: Background, Funding, and Activities (open access)

The Federal Networking and Information Technology Research and Development Program: Background, Funding, and Activities

This report is categorized into four categories: (I) The Federal NITRD Program, (II) Federal Technology Funding Background and Context, (III) Activity in the 112th and 111th Congresses and (IV) Potential Issues for Congress.
Date: August 24, 2011
Creator: Figliola, Patricia Moloney
Object Type: Report
System: The UNT Digital Library
An Evaluation of a Structured Overlapping Grid Implementation of FCT for High-Speed Flows (open access)

An Evaluation of a Structured Overlapping Grid Implementation of FCT for High-Speed Flows

None
Date: August 24, 2011
Creator: Banks, J. W. & Shadid, J. N.
Object Type: Book
System: The UNT Digital Library
Engineering Prototype for a Compact Medical Dielectric Wall Accelerator (open access)

Engineering Prototype for a Compact Medical Dielectric Wall Accelerator

None
Date: August 24, 2011
Creator: Zografos, A.; Hening, A.; Joshkin, V.; Leung, K.; Pearson, D.; Pearce-Percy, H. et al.
Object Type: Article
System: The UNT Digital Library