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Electric Transmission: Approaches for Energizing a Sagging Industry (open access)

Electric Transmission: Approaches for Energizing a Sagging Industry

This report discusses factors that have contributed to the lack of new transmission capacity and some of the resulting issues.
Date: October 3, 2007
Creator: Abel, Amy
Object Type: Report
System: The UNT Digital Library
2006 Electrochemistry Gordon Research Conference - February 12-17-2006 (open access)

2006 Electrochemistry Gordon Research Conference - February 12-17-2006

This report is a descriptive journey of 2006 Electrochemistry Gordon Research Conference.
Date: April 3, 2007
Creator: Abruna, Hector D.
Object Type: Article
System: The UNT Digital Library
Confirmatory Survey Results for the Emergency Operations Facility (EOF) at the Connecticut Yankee Haddam Neck Plant, Haddam, Connecticut (open access)

Confirmatory Survey Results for the Emergency Operations Facility (EOF) at the Connecticut Yankee Haddam Neck Plant, Haddam, Connecticut

The U.S. Nuclear Regulatory Commission (NRC) requested that the Oak Ridge Institute for Science and Education (ORISE) perform a confirmatory survey on the Emergency Operations Facility (EOF) at the Connecticut Yankee Haddam Neck Plant (HNP) in Haddam, Connecticut
Date: July 3, 2007
Creator: Adams, W. C.
Object Type: Report
System: The UNT Digital Library
Supercritical Stability, Transitions, and (Pseudo)tachyons (open access)

Supercritical Stability, Transitions, and (Pseudo)tachyons

Highly supercritical strings (c >> 15) with a time-like linear dilaton provide a large class of solutions to string theory, in which closed string tachyon condensation is under control (and follows the worldsheet renormalization group flow). In this note we analyze the late-time stability of such backgrounds, including transitions between them. The large friction introduced by the rolling dilaton and the rapid decrease of the string coupling suppress the back-reaction of naive instabilities. In particular, although the graviton, dilaton, and other light fields have negative effective mass squared in the linear dilaton background, the decaying string coupling ensures that their condensation does not cause large back-reaction. Similarly, the copious particles produced in transitions between highly supercritical theories do not back-react significantly on the solution. We discuss these features also in a somewhat more general class of time-dependent backgrounds with stable late-time asymptotics.
Date: January 3, 2007
Creator: Aharony, Ofer & Silverstein, Eva
Object Type: Article
System: The UNT Digital Library
Federal Land Ownership: Constitutional Authority and the History of Acquisition, Disposal, and Retention (open access)

Federal Land Ownership: Constitutional Authority and the History of Acquisition, Disposal, and Retention

None
Date: December 3, 2007
Creator: Alexander, Kristina & Gorte, Ross W.
Object Type: Report
System: The UNT Digital Library
Timpson & Tenaha News (Timpson, Tex.), Vol. 24, No. 18, Ed. 1 Thursday, May 3, 2007 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 24, No. 18, Ed. 1 Thursday, May 3, 2007

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: May 3, 2007
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
High power impulse magnetron sputtering: Current-voltage-timecharacteristics indicate the onset of sustained self-sputtering (open access)

High power impulse magnetron sputtering: Current-voltage-timecharacteristics indicate the onset of sustained self-sputtering

The commonly used current-voltage characteristics are foundinadequate for describing the pulsed nature of the high power impulsemagnetron sputtering (HIPIMS) discharge, rather, the description needs tobe expanded to current-voltage-time characteristics for each initial gaspressure. Using different target materials (Cu, Ti, Nb, C, W, Al, Cr) anda pulsed constant-voltage supply it is shown that the HIPIMS dischargestypically exhibit an initial pressure dependent current peak followed bya second phase that is power and material dependent. This suggests thatthe initial phase of a HIPIMS discharge pulse is dominated by gas ionswhereas the later phase has a strong contribution from self-sputtering.For some materials the discharge switches into a mode of sustainedself-sputtering. The very large differences between materials cannot beascribed to the different sputter yields but they indicate thatgeneration and trapping ofsecondary electrons plays a major role forcurrent-voltage-time characteristics. In particular, it is argued thatthe sustained self-sputtering phase is associated with thegeneration ofmultiply charged ions because only they can cause potential emission ofsecondary electrons whereas the yield caused by singly charged metal ionsis negligibly small.
Date: August 3, 2007
Creator: Anders, Andre; Andersson, Joakim & Ehiasarian, Arutiun
Object Type: Article
System: The UNT Digital Library
Heat Transfer Phenomena in Supercritical Water Nuclear Reactors (open access)

Heat Transfer Phenomena in Supercritical Water Nuclear Reactors

A supercritical water heat transfer facility has been built at the University of Wisconsin to study heat transfer in ancircular and square annular flow channel. A series of integral heat transfer measurements has been carried out over a wide range of heat flux, mas velocity and bulk water temperatures at a pressure of 25 MPa. The circular annular test section geometry is a 1.07 cm diameter heater rod within a 4.29 diameter flow channel.
Date: October 3, 2007
Creator: Anderson, Mark H.; Corradini, Michael L.; Bonazza, Riccardo & Licht, Jeremy R.
Object Type: Report
System: The UNT Digital Library
Nanoscale Science and Technology for the Development of Environmental Sensors (open access)

Nanoscale Science and Technology for the Development of Environmental Sensors

Under this funding, we proposed to: i) develop a ChemFET sensor platform, ii) develop a ChemDiode sensor platform, iii) synthesize receptor molecules suitable for chemical sensing, iv) study the electrostatic potential changes induced by receptor/target binding on surfaces and v) develop VLSI fabrication approaches for micron-scale chemical sensor devices. The accomplishments under these various thrusts are summarized in this section.
Date: January 3, 2007
Creator: Andres, Ronald; Janes, David; Clifford Kubiak, Clifford & Reifenberger, Ronald
Object Type: Report
System: The UNT Digital Library
Branching Fraction Measurements of B+ to rho+ gamma,B0 to rho0 gamma, and B0 to omega gamma (open access)

Branching Fraction Measurements of B+ to rho+ gamma,B0 to rho0 gamma, and B0 to omega gamma

The authors present a study of the decays B{sup +} {yields} {rho}{sup +}{gamma}, B{sup 0} {yields} {rho}{sup 0}{gamma}, and B{sup 0} {yields} {omega}{gamma}. The analysis is based on data containing 347 million B{bar B} events recorded with the BABAR detector at the PEP-II asymmetric B factory. They measure the branching fractions {Beta}(B{sup +} {yields} {rho}{sup +}{gamma}) = (1.10{sub -0.33}{sup +0.37} {+-} 0.09) x 10{sup -6} and {Beta}(B{sup 0} {yields} {rho}{sup 0}{gamma}) = (0.79{sub -0.20}{sup +0.22} {+-} 0.06) x 10{sup -6}, and set a 90% C.L. upper limit {Beta}(B{sup 0} {yields} {omega}{gamma}) < 0.78 x 10{sup -6}. They also measure the isospin-averaged branching fraction {Beta}[B {yields} ({rho}/{omega}){gamma}] = (1.25{sub -0.24}{sup +0.25} {+-} 0.09) x 10{sup -6}, from which they determine |V{sub td}/V{sub ts}| = 0.200{sub -0.020}{sup +0.021} {+-} 0.015, where the first uncertainty is experimental and the second is theoretical.
Date: January 3, 2007
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Evidence for B- to rho0rho0 Decay and Implications for the CKM Angle alpha (open access)

Evidence for B- to rho0rho0 Decay and Implications for the CKM Angle alpha

The authors search for the decays B{sup 0} {yields} {rho}{sup 0}{rho}{sup 0}, B{sup 0} {yields} {rho}{sup 0} f{sub 0}(980), and B{sup 0} {yields} f{sub 0}(980) f{sub 0}(980) in a sample of about 384 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at SLAC. They find evidence for B{sup 0} {yields} {rho}{sup 0}{rho}{sup 0} with 3.5{sigma} significance and measure the branching fraction {Beta} = (1.07 {+-} 0.33 {+-} 0.19) x 10{sup -6} and longitudinal polarization fraction f{sub L} = 0.87 {+-} 0.13 {+-} 0.04, where the first uncertainty is statistical, and the second is systematic. The uncertainty on the CKM unitarity angle {alpha} due to penguin contributions in B {yields} {rho}{rho} decays is 18{sup o} at the 1{sigma} level. They also set upper limits on the B{sup 0} {yields} {rho}{sup 0} f{sub 0}(980) and B{sup 0} {yields} f{sub 0}(980)f{sub 0}(980) decay rates.
Date: January 3, 2007
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Fast Laser Excitation and Ultrahigh Strain-Rate Deformation (open access)

Fast Laser Excitation and Ultrahigh Strain-Rate Deformation

Phase evolution induced by single or repeated excitation with energetic femtosecond laser pulses is examined. Of primary interest is the solidification behavior of pure metals at deep undercoolings and self-organization in simple eutectic alloys. Time resolved measurements using third harmonic generation (THG) of light and ultrafast electron diffraction (UED) are employed to elucidate several issues related to fast laser excitation, including heat transport by ballistic and diffusional electrons through multilayer films, the dependence of crystallization velocities on materials properties, mechanisms controlling the transport of heat away from the crystal-liquid interface, and the possibility for quenching pure metals, such as Cu, Ni, and Fe, into the amorphous state. Special samples designed to maximize the quenching speed are developed. The properties of such pure metallic glasses, such as glass and crystallization temperatures, will be measured, if such samples are successfully produced. The measurements are complemented by molecular dynamics computer simulations of the solidification process. The second interest of this research is mesoscopic, self-organization of materials under repeated laser melting, with diffusional relaxation between pulses. We select binary alloys that are immiscible in the solid state but miscible in the liquid state, such as Ag-Cu. Femtosecond laser irradiation is employed to induce melting …
Date: June 3, 2007
Creator: Averback, Robert
Object Type: Report
System: The UNT Digital Library
National Ignition Facility Shot Data Analysis Module Guidelines (open access)

National Ignition Facility Shot Data Analysis Module Guidelines

This document provides the guidelines for software development of modules to be included in Shot Data Analysis (SDA) for the National Ignition Facility (NIF). An Analysis Module is a software entity that groups a set of (typically cohesive) functions, procedures and data structures for performing an analysis task relevant to NIF shot operations. Each module must have its own unique identification (module name), clear interface specifications (data inputs and outputs), and internal documentation. It is vitally important to the NIF Program that all shot-related data be processed and analyzed in a consistent way that is reviewed by scientific and engineering experts. SDA is part of a NIF Integrated Product Team (IPT) whose goal is to provide timely and accurate reporting of shot results to NIF campaign experimentalists. Other elements of the IPT include the Campaign Management Tool (CMT) for configuring experiments, a data archive and provisioning system called CMS, a calibration and configuration database (CDMS), and a shot data visualization tool (SDV). We restrict our scope at this time to guidelines for modules written in Interactive Data Language, or IDL1. This document has sections describing example IDL modules and where to find them, how to set up a development environment, …
Date: October 3, 2007
Creator: Azevedo, S; Glenn, S; Lopez, A; Warrick, A & Beeler, R
Object Type: Report
System: The UNT Digital Library
Advances in U.S. Heavy Ion Fusion Science (open access)

Advances in U.S. Heavy Ion Fusion Science

During the past two years, the US heavy ion fusion science program has made significant experimental and theoretical progress in simultaneous transverse and longitudinal beam compression, ion-beam-driven warm dense matter targets, high-brightness beam transport, advanced theory and numerical simulations, and heavy ion target physics for fusion. First experiments combining radial and longitudinal compression {pi} of intense ion beams propagating through background plasma resulted in on-axis beam densities increased by 700X at the focal plane. With further improvements planned in 2008, these results enable initial ion beam target experiments in warm dense matter to begin next year. They are assessing how these new techniques apply to higher-gain direct-drive targets for inertial fusion energy.
Date: September 3, 2007
Creator: Barnard, J. J.; Logan, B. G.; Bieniosek, F. M.; Cohen, R. H.; Coleman, J. E.; Davidson, R. C. et al.
Object Type: Article
System: The UNT Digital Library

[Students and President Bataille at ISA Diwali event]

Photograph of Gretchen Bataille, President of UNT and chief guest at the Diwali celebration, holding a long candle during the lighting ceremony. Two students are standing next to her dressed in saris and holding small tealight candles.
Date: November 3, 2007
Creator: Baugh, Brian
Object Type: Photograph
System: The UNT Digital Library
Exemptions from Environmental Law for the Department of Defense: Background and Issues for Congress (open access)

Exemptions from Environmental Law for the Department of Defense: Background and Issues for Congress

Over time, Congress has included exemptions in several environmental statutes to ensure that requirements of those statutes would not restrict military training needs to the extent that national security would be compromised. This report discusses these exemptions and congressional disagreement over the need for broader exemptions in the absence of data on the overall impact of environmental requirements on training and readiness.
Date: January 3, 2007
Creator: Bearden, David M.
Object Type: Report
System: The UNT Digital Library
Military Base Closures: Role and Costs of Environmental Cleanup (open access)

Military Base Closures: Role and Costs of Environmental Cleanup

This report explains cleanup requirements for the transfer and reuse of properties on closed military bases, discusses property transfer status and cleanup costs on bases closed in prior rounds, and examines estimates of costs to clean up bases to be closed in the 2005 round to make these properties safe for civilian reuse.
Date: January 3, 2007
Creator: Bearden, David M.
Object Type: Report
System: The UNT Digital Library
National Environmental Education Act of 1990: Overview, Implementation, and Reauthorization Issues (open access)

National Environmental Education Act of 1990: Overview, Implementation, and Reauthorization Issues

None
Date: January 3, 2007
Creator: Bearden, David M.
Object Type: Report
System: The UNT Digital Library
Radioactive Tank Waste from the Past Production of Nuclear Weapons: Background and Issues for Congress (open access)

Radioactive Tank Waste from the Past Production of Nuclear Weapons: Background and Issues for Congress

This report provides background information on the disposal of radioactive tank waste, analyzes the waste disposal authority in P.L. 108-375, discusses the implementation of this authority, and examines relevant issues.
Date: January 3, 2007
Creator: Bearden, David M. & Andrews, Anthony
Object Type: Report
System: The UNT Digital Library
Environmental Protection Agency: FY2007 Appropriations Highlights (open access)

Environmental Protection Agency: FY2007 Appropriations Highlights

This report presents a table detailing EPA appropriations for FY2006 and FY2007. Among individual activities, both the full House and the Senate Appropriations Committee approved decreases and increases throughout EPA's eight appropriations accounts in their respective versions of H.R. 5386, when compared with the President's FY2007 request and the FY2006 appropriation.
Date: January 3, 2007
Creator: Bearden, David M. & Esworthy, Robert
Object Type: Report
System: The UNT Digital Library
Animal Agriculture: Selected Issues for Congress (open access)

Animal Agriculture: Selected Issues for Congress

This report is a brief overview of some selected issues related to animal agriculture that are drawn from CRS reports.
Date: January 3, 2007
Creator: Becker, Geoffrey S.
Object Type: Report
System: The UNT Digital Library
Animal Waste and Hazardous Substances: Current Laws and Legislative Issues (open access)

Animal Waste and Hazardous Substances: Current Laws and Legislative Issues

This report is about the importance of animal identification and its issues.
Date: January 3, 2007
Creator: Becker, Geoffrey S.
Object Type: Report
System: The UNT Digital Library
The Animal Welfare Act: Background and Selected Legislation (open access)

The Animal Welfare Act: Background and Selected Legislation

This report is on The Animal Welfare Act: Background and Selected Legislation.
Date: January 3, 2007
Creator: Becker, Geoffrey S.
Object Type: Report
System: The UNT Digital Library
The “Farm Bill” in Brief (open access)

The “Farm Bill” in Brief

Federal farm support, food assistance, agricultural trade, marketing, and rural development policies are governed by a variety of separate laws. Although many of these policies can be and sometimes are modified through freestanding authorizing legislation, or as part of other laws, the omnibus, multi-year farm bill provides an opportunity for policymakers to address agricultural and food issues more comprehensively.
Date: January 3, 2007
Creator: Becker, Geoffrey S.
Object Type: Report
System: The UNT Digital Library