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Final Technical Report for USDOE Grant No. DE-FG02-96ER14675 Supermolecular Photosynthetic Arrays: Construction, Characterization, Exploration and Utilization (open access)

Final Technical Report for USDOE Grant No. DE-FG02-96ER14675 Supermolecular Photosynthetic Arrays: Construction, Characterization, Exploration and Utilization

Biological processes provide paradigms for the development of solar energy devices of practical utility. In nature, the light harvesting -complexes (LHCs) are not chemically active. However, with unnatural chemical oxidation by potassium ferricyanide, cation free radicals of bacteriochlorophyll (BChl) can be formed in the light harvesting complex 1 (LH1) of Rhodobacter sphaeroides. Based on EPR studies, the site of the BChl{sup +} cations move rather freely about the LH1 complex as in a molecular wire. These molecular wires function in the frozen, solid state. This work seeks to understand better how nature controls electron transfer in some of its molecular wires. To investigate the nature of electron-hole transfer we have e.onducted both electron paramagnetic resonance (EPR) and electron nuclear double resonance (ENDOR) experiments on oxidized LH1 complexes. Progress has been achieved in two main areas: EPR studies of the role of ferricyanide in the molecular wire nature of oxidized LH1; and ENDOR studies of oxidized LH1 at 80K.
Date: December 13, 2009
Creator: Norris, James
System: The UNT Digital Library
2010 Census: Census Bureau Has Made Progress on Schedule and Operational Control Tools, but Needs to Prioritize Remaining System Requirements (open access)

2010 Census: Census Bureau Has Made Progress on Schedule and Operational Control Tools, but Needs to Prioritize Remaining System Requirements

A letter report issued by the Government Accountability Office with an abstract that begins "To carry out the decennial census, the U.S. Census Bureau (Bureau) conducts a sequence of thousands of activities and numerous operations. As requested, The Government Accountability Office (GAO) examined (1) the Bureau's use of scheduling tools to maintain and monitor progress and (2) the status of two systems key to field data collection: the control system the Bureau will use to manage the work flow for paper-based operations, including nonresponse follow-up, and the system used to manage quality control of two major field operations. GAO applied schedule analysis tools; reviewed Bureau evaluations, planning documents, and other documents on work flow management; and interviewed Bureau officials."
Date: November 13, 2009
Creator: United States. Government Accountability Office.
System: The UNT Digital Library
Colombia: Issues for Congress (open access)

Colombia: Issues for Congress

This report provides an overview of recent political developments in Colombia, including the administration of President Uribe (2002-2010), continuing into the election of President Juan Manuel Santos. It discusses the political issues including Colombia's longstanding conflict with internal armed groups and ongoing challenges such as human rights, demobilization and displacement, drug trends, and Colombia's regional relations.
Date: November 13, 2009
Creator: Beittel, June S.
System: The UNT Digital Library
Military and Veterans' Benefits: Analysis of VA Compensation Levels for Survivors of Veterans and Servicemembers (open access)

Military and Veterans' Benefits: Analysis of VA Compensation Levels for Survivors of Veterans and Servicemembers

A letter report issued by the Government Accountability Office with an abstract that begins "The Dependency and Indemnity Compensation (DIC) program provides monthly payments to the survivors of those who died as a result of a service-connected disability or while on active duty in the military. In fiscal year 2008, the Department of Veterans Affairs (VA) paid over $4.7 billion to about 354,000 survivors, replacing a portion of income lost with the death of the veteran or servicemember. The Veterans' Benefits Improvement Act of 2008 directed the Government Accountability Office (GAO) to study the DIC program and the levels of payments it provides. This report addresses (1) the extent to which DIC replaces VA disability compensation or active duty military pay lost due to the death of a veteran or servicemember, and (2) how DIC benefits compare to benefits for survivors of civilian federal employees. GAO obtained and analyzed data on DIC payments, VA disability compensation, and military pay rates. GAO also obtained information on survivor benefits under federal employee retirement and workers' compensation programs. GAO did not include in its analysis other sources of income survivors may receive, such as Social Security, private pensions, and life insurance. Lastly, GAO …
Date: November 13, 2009
Creator: United States. Government Accountability Office.
System: The UNT Digital Library
NEPTUNIUM IV AND V SORPTIN TO END-MEMBER SUBSURFACE SEDIMENTS TO THE SAVANNAH RIVER SITE (open access)

NEPTUNIUM IV AND V SORPTIN TO END-MEMBER SUBSURFACE SEDIMENTS TO THE SAVANNAH RIVER SITE

Migration of Np through the subsurface is expected to be primarily controlled by sorption to sediments. Therefore, understanding and quantifying Np sorption to sediments and sediments from the Savannah River Site (SRS) is vital to ensure safe disposal of Np bearing wastes. In this work, Np sorption to two sediments representing the geological extremes with respect to sorption properties expected in the SRS subsurface environment (named 'subsurface sandy sediment' and 'subsurface clayey sediment') was examined under a variety of conditions. First a series of baseline sorption tests at pH 5.5 under an oxic atmosphere was performed to understand Np sorption under typical subsurface conditions. These experiments indicated that the baseline K{sub d} values for the subsurface sandy and subsurface clayey sediments are 4.26 {+-} 0.24 L kg{sup -1} and 9.05 {+-} 0.61 L kg{sup -1}, respectively. These Np K{sub d} values of SRS sediments are the first to be reported since Sheppard et al. (1979). The previous values were 0.25 and 0.16 L kg{sup -1} for a low pH sandy sediment. To examine a possible range of K{sub d} values under various environmental scenarios, the effects of natural organic matter (NOM, also a surrogate for cellulose degradation products), the presence …
Date: November 13, 2009
Creator: Kaplan, D.
System: The UNT Digital Library
Net Operating Losses: Proposed Extension of Carryback Period (open access)

Net Operating Losses: Proposed Extension of Carryback Period

This report explains the current law regarding the tax treatment of net operating losses (NOLs). In addition, this report highlights a number of policy considerations relating to the extension of the NOL carryback period.
Date: November 13, 2009
Creator: Keightley, Mark P.
System: The UNT Digital Library
Patent “Evergreening”: Issues in Innovation and Competition (open access)

Patent “Evergreening”: Issues in Innovation and Competition

None
Date: November 13, 2009
Creator: unknown
System: The UNT Digital Library
Preliminary simulations of planned experiments to study the impact of trace gases on the capacity of the Weyburn-Midale field to store carbon dioxide (open access)

Preliminary simulations of planned experiments to study the impact of trace gases on the capacity of the Weyburn-Midale field to store carbon dioxide

The CO{sub 2} stream injecting into the Weyburn-Midale field can be generally classified as a reducing stream with residual H{sub 2}S and low-molecular weight hydrocarbons. The composition of the CO{sub 2} gas stream from the Dakota Gasification Company is reported to be 95% CO{sub 2}, 4% hydrocarbons, and 1% H{sub 2}S by volume (Huxley 2006). In addition to the H{sub 2}S introduced at the injection wells, significant concentrations of H{sub 2}S are thought to have been produced in-situ by sulfate reducing bacteria from previous water floods for enhanced oil production. Produced gas compositions range in H{sub 2}S concentrations from 1 to 6 volume percent. The produced gas, including the trace impurities, is re-injected into the field. Although there is no evidence for inorganic reduction of SO{sub 4}{sup 2-} to H{sub 2}S at the Weyburn-Midale field, Sitchler and Kazuba (2009) suggest that SO{sub 4}{sup 2-} can be inorganically reduced to elemental sulfur in highly reducing environments based on a natural analog study of the Madison Formation in Wyoming. They propose that elevated concentrations of CO{sub 2} dissolve anhydrite to produce the sulfate that is then reduced. Oxidizing CO{sub 2} streams with residual O{sub 2} and SO{sub 2} typical of streams captured …
Date: November 13, 2009
Creator: Carroll, S & Hao, Y
System: The UNT Digital Library
Program for the Inspection of Nickel Alloy Components Report from the Program’s Steering Committee: Inspection of Bottom-Mounted Instrumentation Nozzles Round Robin (open access)

Program for the Inspection of Nickel Alloy Components Report from the Program’s Steering Committee: Inspection of Bottom-Mounted Instrumentation Nozzles Round Robin

The U.S. Nuclear Regulatory Commission (NRC) executed agreements with organizations in Japan, Sweden, South Korea, Finland, and the United States to establish the Program for the Inspection of Nickel Alloy Components (PINC).
Date: November 13, 2009
Creator: Cumblidge, Stephen E.; Heasler, Patrick G.; Doctor, Steven R. & Taylor, Theodore T.
System: The UNT Digital Library
RESULTS FOR THE THIRD QUARTER 2009 TANK 50 WAC SLURRY SAMPLE: CHEMICAL AND RADIONUCLIDE CONTAMINANT RESULTS (open access)

RESULTS FOR THE THIRD QUARTER 2009 TANK 50 WAC SLURRY SAMPLE: CHEMICAL AND RADIONUCLIDE CONTAMINANT RESULTS

This report details the chemical and radionuclide contaminant results for the characterization of the 2009 Third Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC). Information from this characterization will be used by Liquid Waste Operations (LWO) to support the transfer of low-level aqueous waste from Tank 50 to the Salt Feed Tank in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50 Waste Characterization System. Recently, a review of the radionuclide inventory in Saltstone Vaults 1 and 4 identified several additional radionuclides, not currently in the WAC, which require quantification ({sup 40}K, {sup 108m}Ag, {sup 133}Ba, {sup 207}Bi, {sup 227}Ac, {sup 228}Ra, {sup 228}Th, {sup 231}Pa, {sup 247}Cm, {sup 249}Cf, {sup 251}Cf). In addition, several of the radionuclides previously reported with minimum detection limits below the requirements listed in the WAC required analysis with reduced detection limits to support future inventory reporting requirements ({sup 22}Na, {sup 26}Al, {sup 59}Ni, {sup 94}Nb, {sup 106}Ru, {sup 144}Ce, {sup 152}Eu, {sup 155}Eu, {sup 226}Ra). This added scope was formally requested in a revision to the standing Technical Task Request for CY2009 Saltstone support and is further discussed …
Date: November 13, 2009
Creator: Reigel, M.; Diprete, C. & Bibler, N.
System: The UNT Digital Library
Sea-Based Ballistic Missile Defense-- Background and Issues for Congress (open access)

Sea-Based Ballistic Missile Defense-- Background and Issues for Congress

This report discusses the changing role and finance of sea-based systems in U.S. ballistic missile defense (BMD). Decisions that Congress reaches on this issue could affect U.S. BMD capabilities and funding requirements; the size, capabilities, and operational patterns of the Navy and the other services; and the shipbuilding industrial base.
Date: November 13, 2009
Creator: O'Rourke, Ronald
System: The UNT Digital Library
U.S. Trade Deficit and the Impact of Changing Oil Prices (open access)

U.S. Trade Deficit and the Impact of Changing Oil Prices

This report provides an estimate of the initial impact of the changing oil prices on the nation's merchandise trade balance.
Date: November 13, 2009
Creator: Jackson, James K.
System: The UNT Digital Library
U.S. Trade Deficit and the Impact of Changing Oil Prices (open access)

U.S. Trade Deficit and the Impact of Changing Oil Prices

None
Date: November 13, 2009
Creator: unknown
System: The UNT Digital Library
Computational fluid dynamics modeling of two-phase flow in a BWR fuel assembly. Final CRADA Report. (open access)

Computational fluid dynamics modeling of two-phase flow in a BWR fuel assembly. Final CRADA Report.

A direct numerical simulation capability for two-phase flows with heat transfer in complex geometries can considerably reduce the hardware development cycle, facilitate the optimization and reduce the costs of testing of various industrial facilities, such as nuclear power plants, steam generators, steam condensers, liquid cooling systems, heat exchangers, distillers, and boilers. Specifically, the phenomena occurring in a two-phase coolant flow in a BWR (Boiling Water Reactor) fuel assembly include coolant phase changes and multiple flow regimes which directly influence the coolant interaction with fuel assembly and, ultimately, the reactor performance. Traditionally, the best analysis tools for this purpose of two-phase flow phenomena inside the BWR fuel assembly have been the sub-channel codes. However, the resolution of these codes is too coarse for analyzing the detailed intra-assembly flow patterns, such as flow around a spacer element. Advanced CFD (Computational Fluid Dynamics) codes provide a potential for detailed 3D simulations of coolant flow inside a fuel assembly, including flow around a spacer element using more fundamental physical models of flow regimes and phase interactions than sub-channel codes. Such models can extend the code applicability to a wider range of situations, which is highly important for increasing the efficiency and to prevent accidents.
Date: October 13, 2009
Creator: Tentner, A.
System: The UNT Digital Library
Final report for grant DE-FG02-06ER64182: "Evaluation and Improvement of the Cloud Resolving Model Component of the Multi-Scale Modeling Framework" (open access)

Final report for grant DE-FG02-06ER64182: "Evaluation and Improvement of the Cloud Resolving Model Component of the Multi-Scale Modeling Framework"

The overall aim of the larger collaborative effort of which this project was part was to evaluate and improve the cloud system resolving model (CSRM) at the heart of the multi-scale modeling framework (MMF). Our task at the University of Colorado our effort was to develop methods that would let us evaluate the performance of cloud-scale models at the ARM SGP site using ARM remote sensing products.
Date: October 13, 2009
Creator: Pincus, Robert
System: The UNT Digital Library
ACRF Instrumentation Status and Information July 2009 (open access)

ACRF Instrumentation Status and Information July 2009

The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.
Date: August 13, 2009
Creator: Voyles, J. W.
System: The UNT Digital Library
Department of Defense Contractors in Iraq and Afghanistan: Background and Analysis (open access)

Department of Defense Contractors in Iraq and Afghanistan: Background and Analysis

The Department of Defense (DOD) increasingly relies upon contractors to support operations in Iraq and Afghanistan, which has resulted in a DOD workforce in those countries comprising approximately a comparable number of contractors (218,000) as uniformed personnel (195,000). This report discusses the issues raised by this fact including (1) what role contractors should play in contingency operations, (2) whether DOD is gathering and analyzing the right data on the use of contractors, (3) what steps DOD is taking to improve contract management and oversight, and (4) the extent to which contractors are being effectively included into military doctrine and strategy. The report examines current contractor trends in Iraq and Afghanistan, the steps DOD has taken to improve contractor oversight and management, and the extent to which DOD has incorporated the role of contractors into its doctrine and strategy. The report also reviews steps Congress has taken to exercise oversight over DOD contracting, including contracting issues that have been the focus of hearings and legislation.
Date: August 13, 2009
Creator: Schwartz, Moshe
System: The UNT Digital Library
EFRT M-12 Issue Resolution: Comparison of Filter Performance at PEP and CUF Scale (open access)

EFRT M-12 Issue Resolution: Comparison of Filter Performance at PEP and CUF Scale

Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed and constructed and is to be operated as part of a plan to respond to issue M12, Undemonstrated Leaching Processes. The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. The PEP also includes non-prototypic ancillary equipment to support the core processing. Two operating scenarios are currently being evaluated for the ultrafiltration process (UFP) and leaching operations. The first scenario has caustic leaching performed in the UFP-2 ultrafiltration feed vessels (i.e., vessel UFP-VSL-T02A in the PEP and vessels UFP-VSL-00002A and B in the WTP PTF). The second scenario has caustic leaching conducted in the UFP-1 ultrafiltration feed-preparation vessels (i.e., vessels UFP-VSL-T01A and B in the PEP; vessels UFP-VSL-00001A and B in the WTP PTF). In both scenarios, 19-M sodium hydroxide solution (NaOH, caustic) is …
Date: August 13, 2009
Creator: Daniel, Richard C.; Billing, Justin M.; Bontha, Jagannadha R.; Brown, Christopher F.; Eslinger, Paul W.; Hanson, Brady D. et al.
System: The UNT Digital Library
Global Health: USAID Programs and Appropriations from FY2001 through FY2010 (open access)

Global Health: USAID Programs and Appropriations from FY2001 through FY2010

This report explains the role USAID plays in U.S. global health assistance, highlights how much the agency has spent on global health efforts from FY2001 to FY2010, discusses how funding to each of its programs has changed during this period, and raises some related policy questions.
Date: August 13, 2009
Creator: Salaam-Blyther, Tiaji
System: The UNT Digital Library
The Individuals with Disabilities Education Act (IDEA): Selected Judicial Developments Following the 2004 Reauthorization (open access)

The Individuals with Disabilities Education Act (IDEA): Selected Judicial Developments Following the 2004 Reauthorization

None
Date: August 13, 2009
Creator: Jones, Nancy Lee & Toland, Carol J.
System: The UNT Digital Library
Moldova: Background and U.S. Policy (open access)

Moldova: Background and U.S. Policy

This report provides information and analysis on Moldova, including its political and economic situation, foreign policy, and U.S. policy toward Moldova.
Date: August 13, 2009
Creator: Woehrel, Steven
System: The UNT Digital Library
Protect and Restore the Upper Lochsa : Annual Progress Report, May 2008 – April 2009. (open access)

Protect and Restore the Upper Lochsa : Annual Progress Report, May 2008 – April 2009.

The Upper Lochsa watersheds included in the project contain critical spawning and rearing habitat for anadromous and resident fish (Clearwater National Forest 1999). Species that depend on the tributary habitat include spring chinook salmon (Oncorhynchus tshawytscha), Snake River summer steelhead (Oncorhynchus mykiss), bull trout (Salvelinus confluentes), and westslope cutthroat trout (Oncorhynchus clarki lewisi). Steelhead and bull trout populations are currently listed as Threatened under the Endangered Species Act (ESA), and westslope cutthroat trout has been petitioned for listing. Both out-of-basin and in-basin factors threaten fish populations in the Lochsa Drainage (Clearwater Subbasin Plan 2003). Out-of-basin factors include the hydroelectric system and ocean conditions, while in-basin factors include a variety of management activities leading to habitat degradation. This project is implemented under Bonneville Power Administration's Fish and Wildlife program in order to meet National Marine Fisheries Service requirements to offset losses caused by the operation of the hydrosystem by improving tributary habitats to promote increased productivity of salmon and steelhead. The Clearwater Subbasin Plan (2003) defines limiting factors to fisheries in the area as watershed disturbances, habitat degradation, sediment, temperature, and connectivity.
Date: August 13, 2009
Creator: Lloyd, Rebecca & Forestieri, David
System: The UNT Digital Library
The Public Safety Employer-Employee Cooperation Act (open access)

The Public Safety Employer-Employee Cooperation Act

This report reviews the Public Safety Employer-Employee Cooperation Act (PSEECA) and discusses the possible impact of the legislation. The report also identifies existing state laws that recognize collective bargaining rights for public safety employees, and considers the constitutional concerns raised by the measure.
Date: August 13, 2009
Creator: Shimabukuro, Jon O. & Mayer, Gerald
System: The UNT Digital Library
Saudi Arabia: Background and U.S. Relations (open access)

Saudi Arabia: Background and U.S. Relations

The kingdom of Saudi Arabia, ruled by the Al Saud family since its founding in 1932, wields significant political and economic influence as the birthplace of the Islamic faith and by virtue of its large energy reserves. This report provides background information about Saudi Arabia and analyzes current issues in U.S.-Saudi relations.
Date: August 13, 2009
Creator: Blanchard, Christopher M.
System: The UNT Digital Library