Ab initio Based Modeling of Radiation Effects in Multi-Component Alloys:  Final Scientific/Technical Report (open access)

Ab initio Based Modeling of Radiation Effects in Multi-Component Alloys: Final Scientific/Technical Report

The project began March 13, 2006, allocated for three years, and received a one year extension from March 13, 2009 to March 12, 2010. It has now completed 48 of 48 total months. The project was focused on using ab initio methods to gain insights into radiation induced segregation (RIS) in Ni-Fe-Cr alloys. The project had the following key accomplishments • Development of a large database of ab initio energetics that can be used by many researchers in the future for increased understanding of this system. For example, we have the first calculations showing a dramatic stabilization effect of Cr-Cr interstitial dumbbells in Ni. • Prediction of both vacancy and interstitial diffusion constants for Ni-Cr and Ni-Fe for dilute Cr and Fe. This work included generalization of widely used multifrequency models to make use of ab initio derived energetics and thermodynamics. • Prediction of qualitative trends of RIS from vacancy and interstitial mechanisms, suggesting the two types of defect fluxes drive Cr RIS in opposite directions. • Detailed kinetic Monte Carlo modeling of diffusion by vacancy mechanism in Ni-Cr as a function of Cr concentration. The results demonstrate that Cr content can have a significant effect on RIS. • Development …
Date: June 10, 2010
Creator: Morgan, Dane
Object Type: Report
System: The UNT Digital Library
The AIG Rescue, Its Impact on Markets, and the Government's Exit Strategy (open access)

The AIG Rescue, Its Impact on Markets, and the Government's Exit Strategy

June report of the U.S. Congressional Oversight Panel describing their activities and findings regarding the impact of the 2007-2008 financial crisis on American International Group (AIG) and the subsequent rescue of the firm by the financial assistance received from the federal government.
Date: June 10, 2010
Creator: United States. Congressional Oversight Panel.
Object Type: Report
System: The UNT Digital Library

Biological Systems for Hydrogen Photoproduction

This presentation summarizes biological systems for hydrogen photoproduction.
Date: June 10, 2010
Creator: Ghirardi, M.
Object Type: Presentation
System: The UNT Digital Library
China Naval Modernization: Implications for U.S. Navy Capabilities--Background and Issues for Congress (open access)

China Naval Modernization: Implications for U.S. Navy Capabilities--Background and Issues for Congress

This report focuses on the potential implications of China's naval modernization for future required U.S. Navy capabilities. This report is based on unclassified open-source information, such as the annual Department of Defense (DOD) report to Congress on China's military power, an August 2009 report from the Office of Naval Intelligence (ONI), and published reference sources such as Jane's Fighting Ships.
Date: June 10, 2010
Creator: O'Rourke, Ronald
Object Type: Report
System: The UNT Digital Library
Consolidation of K Basin Sludge Data and Experiences on Agglomerate Formation (open access)

Consolidation of K Basin Sludge Data and Experiences on Agglomerate Formation

The formation of high sludge strength agglomerates is a key concern to the Sludge Treatment Project (STP) to ensure the sludge can be retrieved after planned storage for up to 10 years in Sludge Transport and Storage Containers (STSC) at T Plant. This report addresses observations of agglomerate formation, conditions that the data shows lead to agglomeration, the frequency of agglomerate formation and postulated physiochemical mechanisms that may lead to agglomeration. Although the exact underlying chemistry of K Basin sludge agglomerate formation is not known, the factors that lead to agglomeration formation, based on observations, are as follows: (1) High Total Uranium Content (i.e., sample homogeneity and influence from other constituents); (2) Distribution of Uranium Phases (i.e., extent of conversion from uraninite to uranium oxide hydroxide compounds); (3) Sample Dry-out (loss of cover water); (4) Elevated temperature; (5) Solubility ofU(IV) phases vs. U(VI) phases; and (6) Long storage times. Agglomerated sludge has occurred infrequently and has only been observed in four laboratory samples, five samples subjected to hydrothermal testing (performed for 7 to 10 hours at {approx}185 C and 225 psig), and indirectly during six sampling events in the KE Basin. In the four laboratory samples where agglomerates were observed, …
Date: June 10, 2010
Creator: Hill, S.R.
Object Type: Report
System: The UNT Digital Library

Controlled Hydrogen Fleet and Infrastructure Analysis

This presentation summarizes controlled hydrogen fleet & infrastructure analysis undertaken for the DOE Fuel Cell Technologies Program.
Date: June 10, 2010
Creator: Wipke, K.; Sprik, S.; Kurtz, J. & Ramsden, T.
Object Type: Presentation
System: The UNT Digital Library
Determination of ionization energies of CnN (n=4-12): Vacuum-ultraviolet (VUV) photoionization experiments and theoretical calculations (open access)

Determination of ionization energies of CnN (n=4-12): Vacuum-ultraviolet (VUV) photoionization experiments and theoretical calculations

Results from single photon vacuum ultraviolet photoionization of astrophysically relevant CnN clusters, n = 4 - 12, in the photon energy range of 8.0 eV to 12.8 eV are presented. The experimental photoionization efficiency curves, combined with electronic structure calculations, provide improved ionization energies of the CnN species. A search through numerous nitrogen-terminated CnN isomers for n=4-9 indicates that the linear isomer has the lowest energy, and therefore should be the most abundant isomer in the molecular beam. Comparison with calculated results also shed light on the energetics of the linear CnN clusters, particularly in the trends of the even-carbon and the odd-carbon series. These results can help guide the search of potential astronomical observations of these neutral molecules together with their cations in highly ionized regions or regions with a high UV/VUV photon flux (ranging from the visible to VUV with flux maxima in the Lyman- region) in the interstellar medium.
Date: June 10, 2010
Creator: Kostko, Oleg; Zhou, Jia; Sun, Bian Jian; Lie, Jie Shiuan; Chang, Agnes H.H.; Kaiser, Ralf I. et al.
Object Type: Article
System: The UNT Digital Library
DOD Leases of Foreign-Built Ships: Background for Congress (open access)

DOD Leases of Foreign-Built Ships: Background for Congress

This report briefly discusses the Department of Defense leasing foreign-built ships, the opponents of this practice, and related legislation.
Date: June 10, 2010
Creator: O'Rourke, Ronald
Object Type: Report
System: The UNT Digital Library
Eagle Nebula Experiments on NIF: NIF Facility Time Proposal (open access)

Eagle Nebula Experiments on NIF: NIF Facility Time Proposal

None
Date: June 10, 2010
Creator: Cooper, A. B.; Remington, B. A.; Pound, M. W.; Moore, A. S.; MacLaren, S. A.; Williams, R. J. et al.
Object Type: Report
System: The UNT Digital Library
Electron and Photon Interactions in the Regime of Strong LPM Suppression (open access)

Electron and Photon Interactions in the Regime of Strong LPM Suppression

Most searches for ultra-high energy (UHE) astrophysical neutrinos look for radio emission from the electromagnetic and hadronic showers produced in their interactions. The radio frequency spectrum and angular distribution depend on the shower development, so are sensitive to the interaction cross sections. At energies above about 1016 eV (in ice), the Landau-Pomeranchuk-Migdal (LPM) effect significantly reduces the cross sections for the two dominant electromagnetic interactions: bremsstrahlung and pair production. At higher energies, above about 1020 eV, the photonuclear cross section becomes larger than that for pair production, and direct pair production and electronuclear interactions become dominant over bremsstrahlung. The electron interaction length reaches a maximum around 1021 eV, and then decreases slowly as the electron energy increases further. In this regime, the growth in the photon cross section and electron energy loss moderates the rise in nu e shower length, which rises from ~;;5 m at 1016 eV to ~;;40 m at 1019 eV and ~;;100 m at 1020 eV, but only to ~;;300 m at 1024 eV. In contrast, without photonuclear and electronuclear interactions, the shower length would be over 10 km at 1024 eV.
Date: June 10, 2010
Creator: Gerhardt, L. & Klein, S.
Object Type: Article
System: The UNT Digital Library
Exploration of Resource and Transmission Expansion Decisions in the Western Renewable Energy Zone Initiative (open access)

Exploration of Resource and Transmission Expansion Decisions in the Western Renewable Energy Zone Initiative

The Western Renewable Energy Zone (WREZ) initiative brings together a diverse set of voices to develop data, tools, and a unique forum for coordinating transmission expansion in the Western Interconnection. In this paper we use a new tool developed in the WREZ initiative to evaluate possible renewable resource selection and transmission expansion decisions. We evaluate these decisions under a number of alternative future scenarios centered on meeting 33percent of the annual load in the Western Interconnection with new renewable resources located within WREZ-identified resource hubs. Our analysis finds that wind energy is the largest source of renewable energy procured to meet the 33percent RE target across nearly all scenarios analyzed (38-65percent). Solar energy is almost always the second largest source (14-41percent). We find several load zones where wind energy is the least cost resource under a wide range of sensitivity scenarios. Load zones in the Southwest, on the other hand, are found to switch between wind and solar, and therefore to vary transmission expansion decisions, depending on uncertainties and policies that affect the relative economics of each renewable option. Further, we find that even with total transmission expenditures of $17-34 billion these costs still represent just 10-19percent of the total …
Date: June 10, 2010
Creator: Mills, Andrew D.; Phadke, Amol A. & Wiser, Ryan H.
Object Type: Article
System: The UNT Digital Library
Federal Register, Volume 75, Number 111, June 10, 2010, Pages 32841-33458 (open access)

Federal Register, Volume 75, Number 111, June 10, 2010, Pages 32841-33458

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: June 10, 2010
Creator: United States. Office of the Federal Register.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Grid-based methods for diatomic quantum scattering problems III: Double photoionization of molecular hydrogen in prolate spheroidal coordinates (open access)

Grid-based methods for diatomic quantum scattering problems III: Double photoionization of molecular hydrogen in prolate spheroidal coordinates

Our previously developed finite-element/ discrete variable representation in prolate spheroidal coordinates is extended to two-electron systems with a study of double ionization of H$_2$ with fixed-nuclei. Particular attention is paid to the development of fast and accurate methods for treating the electron-electron interaction. The use of exterior complex scaling in the implementation offers a simple way of enforcing Coulomb boundary conditions for the electronic double continuum. While the angular distributions calculated in this study are found to be completely consistent with our earlier treatments that employed single-center expansions in spherical coordinates, we find that the magnitude of the integrated cross sections are sensitive to small changes in the initial-state wave function. The present formulation offers significant advantages with respect to convergence and efficiency and opens the way to calculations on more complicated diatomic targets.
Date: June 10, 2010
Creator: Tao, Liang; McCurdy, Bill & Rescigno, Tom
Object Type: Article
System: The UNT Digital Library
Heterotrophic Soil Respiration in Warming Experiments: Using Microbial Indicators to Partition Contributions from Labile and Recalcitrant Soil Organic Carbon. Final Report (open access)

Heterotrophic Soil Respiration in Warming Experiments: Using Microbial Indicators to Partition Contributions from Labile and Recalcitrant Soil Organic Carbon. Final Report

The central objective of the proposed work was to develop a genomic approach (nucleic acid-based) that elucidates the mechanistic basis for the observed impacts of experimental soil warming on forest soil respiration. The need to understand the mechanistic basis arises from the importance of such information for developing effective adaptation strategies for dealing with projected climate change. Specifically, robust predictions of future climate will permit the tailoring of the most effective adaptation efforts. And one of the greatest uncertainties in current global climate models is whether there will be a net loss of carbon from soils to the atmosphere as climate warms. Given that soils contain approximately 2.5 times as much carbon as the atmosphere, a net loss could lead to runaway climate warming. Indeed, most ecosystem models predict that climate warming will stimulate microbial decomposition of soil carbon, producing such a positive feedback to rising global temperatures. Yet the IPCC highlights the uncertainty regarding this projected feedback. The uncertainty arises because although warming-experiments document an initial increase in the loss of carbon from soils, the increase in respiration is short-lived, declining to control levels in a few years. This attenuation could result from changes in microbial physiology with temperature. …
Date: June 10, 2010
Creator: Bradford, M. A.; Melillo, J. M.; Reynolds, J. F.; Treseder, K. K. & Wallenstein, M. D.
Object Type: Report
System: The UNT Digital Library
International Conference on the Cell and Molecular Biology of Chlamydomonas (open access)

International Conference on the Cell and Molecular Biology of Chlamydomonas

The 2010 Conference on the Cell and Molecular Biology of Chlamydomonas was held June 6-10 near Boston, MA, and attracted a record 273 participants, 146 from US labs, 10 from Canada, and the remainder from 18 other countries. The single-celled algal protist Chlamydomonas is a key research organism for many investigators, including those who study photosynthesis, cell motility, adaptation to environmental stresses, the evolution of multicellularity, and the production of biofuels. Chlamydomonas researchers gather every two years at a research conference to exchange methods, develop collaborative efforts, disseminate recent findings, and plan large-scale studies to improve the usefulness of this unique research organism. This conference provides the only opportunity for Chlamydomonas scientists who work on different research problems to meet face to face, and greatly speeds progress in their respective fields. An important function of these Chlamydomonas conferences is to promote and showcase the work of younger scientists, and to attract new investigators into the Chlamydomonas community. DOE award SC0004085 was used to offset the travel and registration costs for 18 young investigators, 9 of whom were women, including one African American. Most of these scientists would not have been able to attend the conference without DOE support. A total …
Date: June 10, 2010
Creator: Miller, Stephen
Object Type: Article
System: The UNT Digital Library
Liquid X-ray diffraction on the NIF: Phase transitions into and within the liquid phase (open access)

Liquid X-ray diffraction on the NIF: Phase transitions into and within the liquid phase

None
Date: June 10, 2010
Creator: Eggert, J
Object Type: Report
System: The UNT Digital Library
Magnetic frustration effects in uranium intermetallics (open access)

Magnetic frustration effects in uranium intermetallics

The effect of geometrical frustration on the development of the heavy-fermion state and quantum criticality is studied in UAuCu{sub 4}, UAuPt{sub 4}, UAu{sub 3}Ni{sub 2} samples through measurements of their magnetic susceptibility, heat capacity, and electrical resistivity. In addition, since lattice disorder can play a large role in defining magnetic properties in frustrated systems, extended X-ray absorption fine structure (EXAFS) data have also been obtained. The local structure results show a strong correlation with the magnetic properties in these samples.
Date: June 10, 2010
Creator: Jiang, Yu; Booth, C. H.; Tobash, P. H.; Gofryk, K.; Torrez, M. A.; Ronning, F. et al.
Object Type: Article
System: The UNT Digital Library
Materials at Atomic Pressure (open access)

Materials at Atomic Pressure

None
Date: June 10, 2010
Creator: Hicks, D
Object Type: Report
System: The UNT Digital Library
Navy Aegis Ballistic Missile Defense (BMD) Program: Background and Issues for Congress (open access)

Navy Aegis Ballistic Missile Defense (BMD) Program: Background and Issues for Congress

This report discusses the Aegis ballistic missile defense (BMD) program. Under current Missile Defense Agency (MDA) and Navy plans, the number of BMD-capable Navy Aegis ships is schedule to grow from 20 at the end of FY2010 to 38 at the end of FY2015. This report discusses the concerns some have over BMD expansion, as well as BMD funding issues.
Date: June 10, 2010
Creator: O'Rourke, Ronald
Object Type: Report
System: The UNT Digital Library
Navy Aegis Cruiser and Destroyer Modernization: Background and Issues for Congress (open access)

Navy Aegis Cruiser and Destroyer Modernization: Background and Issues for Congress

The Navy has begun a multi-billion dollar program to modernize its 84 existing Aegis cruisers and destroyers over a period of more than 20 years. This report explores this program in detail, including the reasons for the program and the oversight issues it poses for Congress.
Date: June 10, 2010
Creator: O'Rourke, Ronald
Object Type: Report
System: The UNT Digital Library
Navy CG(X) Cruiser Program: Background for Congress (open access)

Navy CG(X) Cruiser Program: Background for Congress

The Navy's FY2011 budget proposes canceling the CG(X) program as unaffordable and instead building an improved version of the Arleigh Burke (DDG-51) class Aegis destroyer called the Flight III version. This report provides background information on the CG(X) program as it existed prior to its proposed cancellation.
Date: June 10, 2010
Creator: O'Rourke, Ronald
Object Type: Report
System: The UNT Digital Library
Navy DDG-51 and DDG-1000 Destroyer Programs: Background and Issues for Congress (open access)

Navy DDG-51 and DDG-1000 Destroyer Programs: Background and Issues for Congress

This report discusses issues Congress faces regarding the Navy's proposed FY2011 budget, particularly as relating to destroyer procurement plans and programs.
Date: June 10, 2010
Creator: O'Rourke, Ronald
Object Type: Report
System: The UNT Digital Library
Navy Force Structure and Shipbuilding Plans: Background and Issues for Congress (open access)

Navy Force Structure and Shipbuilding Plans: Background and Issues for Congress

This report provides background information and presents potential issues for Congress concerning the Navy's ship force-structure goals and shipbuilding plans. The planned size of the Navy, the rate of Navy ship procurement, and the prospective affordability of the Navy's shipbuilding plans have been matters of concern for the congressional defense committees for the past several years. Decisions that Congress makes on Navy shipbuilding programs can substantially affect Navy capabilities and funding requirements, and the U.S. shipbuilding industrial base.
Date: June 10, 2010
Creator: O'Rourke, Ronald
Object Type: Report
System: The UNT Digital Library
Navy Ford (CVN-78) Class Aircraft Carrier Program: Background and Issues for Congress (open access)

Navy Ford (CVN-78) Class Aircraft Carrier Program: Background and Issues for Congress

This report provides background information and potential oversight issues for Congress on the CVN-78 program, which includes the CVN-78, CVN-79, and CVN-80 as the first three ships in the Navy's new Gerald R. Ford (CVN- 78) class of nuclear-powered aircraft carriers (CVNs).
Date: June 10, 2010
Creator: O'Rourke, Ronald
Object Type: Report
System: The UNT Digital Library