Depot Maintenance: Air Force Is Assessing Engine Maintenance Options for Work Currently Performed at Kelly Aviation Center (open access)

Depot Maintenance: Air Force Is Assessing Engine Maintenance Options for Work Currently Performed at Kelly Aviation Center

Correspondence issued by the Government Accountability Office with an abstract that begins "This report responds to questions that Congress raised about Air Force engine maintenance and repair work currently performed at Kelly Aviation Center (KAC) and the potential transfer of that work to another location. In 1999, Oklahoma City Air Logistics Center (OC-ALC) awarded a contract to KAC to perform work, including depot-level maintenance, repair, and overhaul on TF39 engines, which are typically used for C-5 Galaxy aircraft; T56 engines, which are typically used for C-130 aircraft; and fuel accessories on these engines. The Air Force estimates the total expenditure under the contract for this work to be $3.7 billion from February 16, 1999, through December 1, 2010. The contract is not to exceed 15 years (the contract had an initial 7-year ordering period that could be extended to 15 years or reduced to 5 years based on performance), and will expire not later than February 15, 2014. The Air Force will need to determine how to conduct the engine maintenance work after the term of the contract ends. Congress requested that we review the potential transfer of the engine maintenance and repair workload from KAC. Our objectives were to …
Date: February 11, 2011
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Texas Register, Volume 36, Number 6, Pages 685-884, February 11, 2011 (open access)

Texas Register, Volume 36, Number 6, Pages 685-884, February 11, 2011

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: February 11, 2011
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Searching for optimal mitigation geometries for laser resistant multilayer high reflector coatings (open access)

Searching for optimal mitigation geometries for laser resistant multilayer high reflector coatings

Growing laser damage sites on multilayer high reflector coatings can limit mirror performance. One of the strategies to improve laser damage resistance is to replace the growing damage sites with pre-designed benign mitigation structures. By mitigating the weakest site on the optic, the large aperture mirror will have a laser resistance comparable to the intrinsic value of the multilayer coating. To determine the optimal mitigation geometry, the finite difference time domain method (FDTD) was used to quantify the electric-field intensification within the multilayer, at the presence of different conical pits. We find that the field intensification induced by the mitigation pit is strongly dependent on the polarization and the angle of incidence (AOI) of the incoming wave. Therefore the optimal mitigation conical pit geometry is application specific. Furthermore, our simulation also illustrates an alternative means to achieve an optimal mitigation structure by matching the cone angle of the structure with the AOI of the incoming wave, except for the p-polarization wave at a range of incident angles between 30{sup o} and 45{sup o}.
Date: February 11, 2011
Creator: Qiu, S R; Wolfe, J E; Monterrosa, A M; Feit, M D; Pistor, T V & STolz, C J
Object Type: Article
System: The UNT Digital Library
Order and disorder in the local and long-range structure of the spin-glass pyrochlore, Tb{sub 2}Mo{sub 2}O{sub 7} (open access)

Order and disorder in the local and long-range structure of the spin-glass pyrochlore, Tb{sub 2}Mo{sub 2}O{sub 7}

To understand the origin of the spin-glass state in molybdate pyrochlores, the structure of Tb{sub 2}Mo{sub 2}O{sub 7} is investigated using two techniques: the long-range lattice structure was measured using neutron powder diffraction (NPD), and local structure information was obtained from the extended x-ray absorption fine structure (EXAFS) technique. While the long-range structure appears generally well ordered, enhanced mean-squared site displacements on the O(1) site and the lack of temperature dependence of the strongly anisotropic displacement parameters for both the Mo and O(1) sites indicate some disorder exists. Likewise, the local structure measurements indicate some Mo-Mo and Tb-O(1) nearest-neighbor disorder exists, similar to that found in the related spin-glass pyrochlore, Y{sub 2}Mo{sub 2}O{sub 7}. Although the freezing temperature in Tb{sub 2}Mo{sub 2}O{sub 7}, 25 K, is slightly higher than in Y{sub 2}Mo{sub 2}O{sub 7}, 22 K, the degree of local pair distance disorder is actually less in Tb{sub 2}Mo{sub 2}O{sub 7}. This apparent contradiction is considered in light of the interactions involved in the freezing process.
Date: February 11, 2011
Creator: Jiang, Yu; Huq, Ashfia; Booth, Corwin H.; Ehlers, Georg; Greedan, John E. & Gardner, Jason S.
Object Type: Article
System: The UNT Digital Library
X-ray imaging of vortex cores in confined magnetic structures (open access)

X-ray imaging of vortex cores in confined magnetic structures

Cores of magnetic vortices in micron-sized NiFe disk structures, with thicknesses between 150 and 50 nm, were imaged and analysed by high resolution magnetic soft X-ray microscopy. A decrease of the vortex core radius was observed, from #24; ~38 to 18 nm with decreasing disk thickness. By comparing with full 3D micromagnetic simulations showing the well-known barrel structure, we obtained excellent agreement taking into account instrumental broadening and a small perpendicular anisotropy. The proven magnetic spatial resolution of better than 25 nm was sufficient to identify a negative dip close to the vortex core, originating from stray fields of the core. Magnetic vortex structures can serve as test objects for evaluating sensitivity and spatial resolution of advanced magnetic microscopy techniques.
Date: February 11, 2011
Creator: Fischer, P.; Im, M.-Y.; Kasai, S.; Yamada, K.; Ono, T. & Thiaville, A.
Object Type: Article
System: The UNT Digital Library
SUMMARY PLAN FOR BENCH-SCALE REFORMER AND PRODUCT TESTING TREATABILITY STUDIES USING HANFORD TANK WASTE (open access)

SUMMARY PLAN FOR BENCH-SCALE REFORMER AND PRODUCT TESTING TREATABILITY STUDIES USING HANFORD TANK WASTE

This paper describes the sample selection, sample preparation, environmental, and regulatory considerations for shipment of Hanford radioactive waste samples for treatability studies of the FBSR process at the Savannah River National Laboratory and the Pacific Northwest National Laboratory.
Date: February 11, 2011
Creator: Robbins, R. A.
Object Type: Report
System: The UNT Digital Library
DATA QUALITY OBJECTIVES FOR SELECTING WASTE SAMPLES FOR BENCH-SCALE REFORMER TREATABILITY STUDIES (open access)

DATA QUALITY OBJECTIVES FOR SELECTING WASTE SAMPLES FOR BENCH-SCALE REFORMER TREATABILITY STUDIES

This document describes the data quality objectives to select archived samples located at the 222-S Laboratory for Bench-Scale Reforming testing. The type, quantity, and quality of the data required to select the samples for Fluid Bed Steam Reformer testing are discussed. In order to maximize the efficiency and minimize the time to treat Hanford tank waste in the Waste Treatment and Immobilization Plant, additional treatment processes may be required. One of the potential treatment processes is the fluidized bed steam reformer. A determination of the adequacy of the fluidized bed steam reformer process to treat Hanford tank waste is required. The initial step in determining the adequacy of the fluidized bed steam reformer process is to select archived waste samples from the 222-S Laboratory that will be used in a bench scale tests. Analyses of the selected samples will be required to confirm the samples meet the shipping requirements and for comparison to the bench scale reformer (BSR) test sample selection requirements.
Date: February 11, 2011
Creator: DL, BANNING
Object Type: Report
System: The UNT Digital Library
Mask roughness induced LER: geometric model at long correlation lengths (open access)

Mask roughness induced LER: geometric model at long correlation lengths

Collective understanding of how both the resist and line-edge roughness (LER) on the mask affect the final printed LER has made significant advances. What is poorly understood, however, is the extent to which mask surface roughness couples to image plane LER as a function of illumination conditions, NA, and defocus. Recently, progress has been made in formulating a simplified solution for mask roughness induced LER. Here, we investigate the LER behavior at long correlation lengths of surface roughness on the mask. We find that for correlation lengths greater than 3/NA in wafer dimensions and CDs greater than approximately 0.75/NA, the previously described simplified model, which remains based on physical optics, converges to a 'geometric regime' which is based on ray optics and is independent of partial coherence. In this 'geometric regime', the LER is proportional to the mask slope error as it propagates through focus, and provides a faster alternative to calculating LER in contrast to either full 2D aerial image simulation modeling or the newly proposed physical optics model. Data is presented for both an NA = 0.32 and an NA = 0.5 imaging system for CDs of 22-nm and 50-nm horizontal-line-dense structures.
Date: February 11, 2011
Creator: McClinton, Brittany M. & Naulleau, Patrick P.
Object Type: Article
System: The UNT Digital Library
Structural and electronic properties of dense liquid and amorphous nitrogen (open access)

Structural and electronic properties of dense liquid and amorphous nitrogen

We present first-principles calculations of the structural and electronic properties of liquid nitrogen in the pressure-temperature range of 0-200 GPa and 2000-6000 K. The molecular-polymerization and molecular-atomic liquid phase boundaries have been mapped over this region. We find the polymeric liquid to be metallic, similar to what has been reported for the higher-temperature atomic fluid. An explanation of the electronic properties is given based on the structure and bonding character of the transformed liquids. We discuss the structural and bonding differences between the polymeric liquid and insulating solid cubic-gauche nitrogen to explain the differences in their electronic properties. Furthermore, we discuss the mechanism responsible for charge transport in polymeric nitrogen systems to explain the conductivity of the polymeric fluid and the semi-conducting nature of low-temperature amorphous nitrogen.
Date: February 11, 2011
Creator: Boates, B & Bonev, S A
Object Type: Article
System: The UNT Digital Library
Hydration of gas-phase ytterbium ion complexes studied by experiment and theory (open access)

Hydration of gas-phase ytterbium ion complexes studied by experiment and theory

Hydration of ytterbium (III) halide/hydroxide ions produced by electrospray ionization was studied in a quadrupole ion trap mass spectrometer and by density functional theory (DFT). Gas-phase YbX{sub 2}{sup +} and YbX(OH){sup +} (X = OH, Cl, Br, or I) were found to coordinate from one to four water molecules, depending on the ion residence time in the trap. From the time dependence of the hydration steps, relative reaction rates were obtained. It was determined that the second hydration was faster than both the first and third hydrations, and the fourth hydration was the slowest; this ordering reflects a combination of insufficient degrees of freedom for cooling the hot monohydrate ion and decreasing binding energies with increasing hydration number. Hydration energetics and hydrate structures were computed using two approaches of DFT. The relativistic scalar ZORA approach was used with the PBE functional and all-electron TZ2P basis sets; the B3LYP functional was used with the Stuttgart relativistic small-core ANO/ECP basis sets. The parallel experimental and computational results illuminate fundamental aspects of hydration of f-element ion complexes. The experimental observations - kinetics and extent of hydration - are discussed in relationship to the computed structures and energetics of the hydrates. The absence of …
Date: February 11, 2011
Creator: Rutkowski, Philip X; Michelini, Maria C.; Bray, Travis H.; Russo, Nino; Marcalo, Joaquim & Gibson, John K.
Object Type: Article
System: The UNT Digital Library
Commercial Air-Source Heat Pumps, Purchasing Specifications for Energy-Efficient Products (Fact Sheet) (open access)

Commercial Air-Source Heat Pumps, Purchasing Specifications for Energy-Efficient Products (Fact Sheet)

Energy efficiency purchasing specifications for federal procurements of commercial air-source heat pumps.
Date: February 11, 2011
Creator: unknown
Object Type: Report
System: The UNT Digital Library
2011 Chemical Reactions at Surfaces Gordon Research Conference (open access)

2011 Chemical Reactions at Surfaces Gordon Research Conference

The Gordon Research Conference on Chemical Reactions at Surfaces is dedicated to promoting and advancing the fundamental science of interfacial chemistry and physics by providing surface scientists with the foremost venue for presentation and discussion of research occurring at the frontiers of their fields.
Date: February 11, 2011
Creator: Stair, Peter
Object Type: Article
System: The UNT Digital Library
In situ optimization of co-implantation and substrate temperature conditions for Nitrogen-Vacancy center formation in single crystal diamonds (open access)

In situ optimization of co-implantation and substrate temperature conditions for Nitrogen-Vacancy center formation in single crystal diamonds

None
Date: February 11, 2011
Creator: Schwartz, J.; Michaelides, P.; Weis, C. D. & Schenkel, T.
Object Type: Article
System: The UNT Digital Library
Report on Initial Direct Soil Leaching Experiments Using Post-Detonation Debris (open access)

Report on Initial Direct Soil Leaching Experiments Using Post-Detonation Debris

None
Date: February 11, 2011
Creator: Gostic, R; Knight, K B & Borg, L
Object Type: Report
System: The UNT Digital Library
Implementation Plan for the Deep Vadose Zone-Applied Field Research Center (open access)

Implementation Plan for the Deep Vadose Zone-Applied Field Research Center

The Long-Range Deep Vadose Zone Program Plan was published in October 2010. It summarized the U.S. Department of Energy’s (DOE’s) state-of-knowledge about the contaminant remediation challenges facing the deep vadose zone (DVZ) beneath the Central Plateau of the Hanford Site and their approach to solving those challenges. Developing an implementation plan is the next step to address the knowledge and capabilities required to solve DVZ challenges when needed. This multi-year plan (FY-11 through FY-20) identifies the short to long-term research, management, and execution plans required to solve those problems facing the DVZ-Applied Field Research Center (DVZ-AFRC). The schedule supporting implementation overlies existing activities and milestones from Hanford’s DOE-Environmental Management (EM) end-user projects. Success relies upon multi-project teams focused on coordinated subsurface projects undertaken across the DOE Complex combined with facilitated, problem-focused, research investments implemented through the DVZ-AFRC.
Date: February 11, 2011
Creator: Wellman, Dawn M.; Truex, Michael J.; Freshley, Mark D.; Gephart, Roy E.; Triplett, Mark B. & Johnson, Timothy C.
Object Type: Report
System: The UNT Digital Library
The Speaker of the House: House Officer, Party Leader, and Representative (open access)

The Speaker of the House: House Officer, Party Leader, and Representative

This report discusses the three roles of the Speaker of the House of Representatives, who is widely viewed as symbolizing the power and authority of the House. The Speaker's most prominent role is that of presiding officer of the House. The Speaker also serves as leader of the majority party conference. The Speaker's third distinct role is that of an elected Member of the House.
Date: February 11, 2011
Creator: Heitshusen, Valerie
Object Type: Report
System: The UNT Digital Library
Committee Types and Roles (open access)

Committee Types and Roles

This report briefly describes the structure of the congressional committee system and the types of congressional committees, as well as congressional subcommittees.
Date: February 11, 2011
Creator: Heitshusen, Valerie
Object Type: Report
System: The UNT Digital Library
Federal Register, Volume 76, Number 28, February 11, 2011, Pages 7479-7680 (open access)

Federal Register, Volume 76, Number 28, February 11, 2011, Pages 7479-7680

Daily publication of the U.S. Office of the Federal Register contains rules and regulations, proposed legislation and rule changes, and other notices, including "Presidential proclamations and Executive Orders, Federal agency documents having general applicability and legal effect, documents required to be published by act of Congress, and other Federal agency documents of public interest" (p. ii). Table of Contents starts on page iii.
Date: February 11, 2011
Creator: United States. Office of the Federal Register.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
The Market for Biomass-Based Diesel Fuel in the Renewable Fuel Standard (RFS) (open access)

The Market for Biomass-Based Diesel Fuel in the Renewable Fuel Standard (RFS)

This report discusses the current market for biomass-based diesel (BBD) fuels and their corresponding RINs (Renewable Identification Numbers) under the RFS. It examines the role that the RIN market may play as an economic incentive for the production of biodiesel and other BBD fuels in the future.
Date: February 11, 2011
Creator: Yacobucci, Brent D.
Object Type: Report
System: The UNT Digital Library
Implications of Egypt's Turmoil on Global Oil and Natural Gas Supply (open access)

Implications of Egypt's Turmoil on Global Oil and Natural Gas Supply

This report examines the change in Egypt's government and how this will likely not have a significant direct impact on the global oil and natural gas markets.
Date: February 11, 2011
Creator: Ratner, Michael
Object Type: Report
System: The UNT Digital Library
Reaching the Debt Limit: Background and Potential Effects on Government Operations (open access)

Reaching the Debt Limit: Background and Potential Effects on Government Operations

This report examines the possibility of the federal government reaching its statutory debt limit and not raising it, with a particular focus on government operations. First, the report explains the nature of the federal government's debt, the processes associated with federal borrowing, and historical events that may influence prospective actions. It also includes an analysis of what could happen if the federal government may no longer issue debt, has exhausted alternative sources of cash, and, therefore, depends on incoming receipts or other sources of funds to provide any cash needed to liquidate federal obligations. Finally this report lays out considerations for increasing the debt limit under current policy and what impact fiscal policy could have on the debt limit going forward.
Date: February 11, 2011
Creator: Levit, Mindy R.; Brass, Clinton T.; Nicola, Thomas J.; Nuschler, Dawn & Shelton, Alison M.
Object Type: Report
System: The UNT Digital Library
Party Leaders in the United States Congress, 1789-2011 (open access)

Party Leaders in the United States Congress, 1789-2011

This report briefly describes current responsibilities and selection mechanisms for 15 House and Senate party leadership posts and provides tables with historical data, including service dates, party affiliation, and other information for each.
Date: February 11, 2011
Creator: Heitshusen, Valerie
Object Type: Report
System: The UNT Digital Library
Egypt: The January 25 Revolution and Implications for U.S. Foreign Policy (open access)

Egypt: The January 25 Revolution and Implications for U.S. Foreign Policy

This report provides an overview of Egyptian politics and current issues in U.S.-Egyptian relations. It briefly provides a political history of modern Egypt, an overview of its political institutions, and a discussion of the prospects for democratization in Egypt.
Date: February 11, 2011
Creator: Sharp, Jeremy M.
Object Type: Report
System: The UNT Digital Library
Intelligence Issues for Congress (open access)

Intelligence Issues for Congress

This report gives an overview of current intelligence issues of interest to the 112th Congress. It includes background and analysis including most recent development, ongoing Congressional concerns, specific issues for the 112th Congress, and a summary of related legislation from the 109th through the 112th Congresses.
Date: February 11, 2011
Creator: Best, Richard A., Jr.
Object Type: Report
System: The UNT Digital Library