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Measurement of the Inelastic Proton-Proton Cross-Section at sqrt{s}=7 TeV with the ATLAS Detector (open access)

Measurement of the Inelastic Proton-Proton Cross-Section at sqrt{s}=7 TeV with the ATLAS Detector

None
Date: June 5, 2013
Creator: Aad, Georges
System: The UNT Digital Library
Pressure-induced isostructural transition in PdN2 (open access)

Pressure-induced isostructural transition in PdN2

We show that a synthesized Pd-N compound crystallize into the pyrite structure by comparison of experimental and calculated Raman intensities. The decreasing Raman intensities with decreasing pressure is explained by a closing of the fundamental band gap. We further discuss the experimental decomposition of this compound at 11 GPa in terms of an isostructural transition within the pyrite structure.
Date: March 5, 2010
Creator: Aberg, D; Erhart, P; Crowhurst, J; Zaug, J M; Goncharov, A F & Sadigh, B
System: The UNT Digital Library
RECERTIFICATION OF THE MODEL 9977 RADIOACTIVE MATERIAL PACKAGING (open access)

RECERTIFICATION OF THE MODEL 9977 RADIOACTIVE MATERIAL PACKAGING

The Model 9977 Packaging was initially issued a Certificate of Compliance (CoC) by the Department of Energy’s Office of Environmental Management (DOE-EM) for the transportation of radioactive material (RAM) in the Fall of 2007. This first CoC was for a single radioactive material and two packing configurations. In the five years since that time, seven Addendums have been written to the Safety Analysis Report for Packaging (SARP) and five Letter Amendments have been written that have authorized either new RAM contents or packing configurations, or both. This paper will discuss the process of updating the 9977 SARP to include all the contents and configurations, including the addition of a new content, and its submittal for recertification.
Date: June 5, 2013
Creator: Abramczyk, G.; Bellamy, S.; Loftin, B. & Nathan, S.
System: The UNT Digital Library
PRECEDENTS FOR AUTHORIZATION OF CONTENTS USING DOSE RATE MEASUREMENTS (open access)

PRECEDENTS FOR AUTHORIZATION OF CONTENTS USING DOSE RATE MEASUREMENTS

For the transportation of Radioactive Material (RAM) packages, the requirements for the maximum allowed dose rate at the package surface and in its vicinity are given in Title 10 of the Code of Federal Regulations, Section 71.47. The regulations are based on the acceptable dose rates to which the public, workers, and the environment may be exposed. As such, the regulations specify dose rates, rather than quantity of radioactive isotopes and require monitoring to confirm the requirements are met. 10CFR71.47 requires that each package of radioactive materials offered for transportation must be designed and prepared for shipment so that under conditions normally incident to transportation the radiation level does not exceed 2 mSv/h (200 mrem/h) at any point on the external Surface of the package, and the transport index does not exceed 10. Before shipment, the dose rate of the package is determined by measurement, ensuring that it conforms to the regulatory limits, regardless of any analyses. This is the requirement for all certified packagings. This paper discusses the requirements for establishing the dose rates when shipping RAM packages and the precedents for meeting these requirements by measurement.
Date: June 5, 2012
Creator: Abramczyk, G.; Bellamy, S.; Nathan, S. & Loftin, B.
System: The UNT Digital Library
Generalized molecular solvation in non-aqueous solutions by a single parameter implicit solvation scheme (open access)

Generalized molecular solvation in non-aqueous solutions by a single parameter implicit solvation scheme

Article presenting a systematic parametrization protocol for the Self-Consistent Continuum Solvation (SCCS) model resulting in optimized parameters for 67 non-aqueous solvents. The parametrization is based on a collection of ≈6000 experimentally measured partition coefficients, which were collected in the Solv@TUM database presented here. The accuracy of the optimized SCCS model is comparable to the well-known universal continuum solvation model (SMx) family of methods, while relying on only a single fit parameter and thereby largely reducing statistical noise.
Date: August 3, 2018
Creator: Acree, William E. (William Eugene); Hille, Christoph; Ringe, Stefan; Deimel, Martin; Kunkel, Christian; Reuter, Karsten et al.
System: The UNT Digital Library
Improving Conservation for First-Order System Least Squares Finite-Element Methods (open access)

Improving Conservation for First-Order System Least Squares Finite-Element Methods

None
Date: September 5, 2012
Creator: Adler, J H & Vassilevski, P S
System: The UNT Digital Library
Improved resolution of hydrocarbon structures and constitutional isomers in complex mixtures using Gas Chromatography-Vacuum Ultraviolet-Mass Spectrometry (GC-VUV-MS) (Supplementary Info) (open access)

Improved resolution of hydrocarbon structures and constitutional isomers in complex mixtures using Gas Chromatography-Vacuum Ultraviolet-Mass Spectrometry (GC-VUV-MS) (Supplementary Info)

Understanding the composition of complex hydrocarbon mixtures is important for environmental studies in a variety of fields, but many prevalent compounds cannot be confidently identified using traditional gas chromatography-mass spectrometry (GC-MS) techniques. This work uses vacuum-ultraviolet (VUV) ionization to elucidate the structures of a traditionally"unresolved complex mixture" by separating components by GC retention time, tR, and mass-to-charge ratio, m/Q, which are used to determine carbon number, NC, and the number of rings and double bonds, NDBE. Constitutional isomers are resolved based on tR, enabling the most complete quantitative analysis to date of structural isomers in an environmentally-relevant hydrocarbon mixture. Unknown compounds are classified in this work by carbon number, degree of saturation, presence of rings, and degree of branching, providing structural constraints. The capabilities of this analysis are explored using diesel fuel, in which constitutional isomer distribution patterns are shown to be reproducible between carbon numbers and follow predictable rules. Nearly half of the aliphatic hydrocarbon mass is shown to be branched, suggesting branching is more important in diesel fuel than previously shown. The classification of unknown hydrocarbons and the resolution of constitutional isomers significantly improves resolution capabilities for any complex hydrocarbon mixture.
Date: September 5, 2011
Creator: Aerosol Dynamics Inc.,; Aerodyne Research, Inc.,; Tofwerk AG, Thun, Switzerland; Isaacman, Gabriel; Wilson, Kevin R.; Chan, Arthur W. H. et al.
System: The UNT Digital Library
Giant cross-magnetic-field steps due to binary collisions between pair particles (open access)

Giant cross-magnetic-field steps due to binary collisions between pair particles

Article explores giant cross-magnetic-field steps which occur as a result of positron-electron collisions. Within a constant magnetic field (e.g., 1 T), a collision between a positron and an electron can result in a correlated drift across the magnetic field for a continuous range of impact parameters. Within this range, drift distances orders of magnitude larger than that associated with like-charge collisions were observed by computer simulation.
Date: March 5, 2015
Creator: Aguirre, F. F. & Ordonez, Carlos A.
System: The UNT Digital Library
Giant increase in cross-magnetic-field transport rate as an electron-positron plasma cools (open access)

Giant increase in cross-magnetic-field transport rate as an electron-positron plasma cools

The article focuses on a study of an electron-positron plasma in thermal equilibrium within a uniform magnetic field using a classical trajectory Monte Carlo simulation. The cross-magnetic-field single-particle diffusion coefficient is evaluated as a function of the magnetic field strength and plasma temperature. The transport rate is found to increase by many orders of magnitude as the plasma temperature is lowered, for a magnetic field strength of 1 T. The sharp dependence on temperature is due to electrons and positrons becoming temporarily correlated and drifting across the magnetic field before dissociating.
Date: October 5, 2017
Creator: Aguirre, F. F. & Ordonez, Carlos A.
System: The UNT Digital Library
MAP training: combining meditation and aerobic exercise reduces depression and rumination while enhancing synchronized brain activity (open access)

MAP training: combining meditation and aerobic exercise reduces depression and rumination while enhancing synchronized brain activity

This article discusses the efficacy of mental and physical (MAP) training in improving symptoms of depression and rumination in individuals with major depressive disorder (MDD).
Date: October 5, 2015
Creator: Alderman, Brandon L.; Olson, Ryan L.; Brush, Christopher J. & Shors, Tracey J.
System: The UNT Digital Library
Gene by Disease Interaction on Orbitofrontal Gray Matter in Cocaine Addiction (open access)

Gene by Disease Interaction on Orbitofrontal Gray Matter in Cocaine Addiction

Chronic cocaine use has been associated with structural deficits in brain regions having dopamine receptive neurons. However, the concomitant use of other drugs and common genetic variability in monoamine regulation present additional structural variability. We therefore examined variations in gray matter volume (GMV) as a function of lifetime drug use and the monoamine oxidase A (MAOA) genotype in cocaine use disorders (CUD) and healthy controls.
Date: December 5, 2010
Creator: Alia-Klein, N.; Alia-Klein, N.; Parvaz, M. A.; Woicik, P. A.; Konova, A.; Maloney, T. et al.
System: The UNT Digital Library
The FERMI@Elettra free-electron-laser source for coherent X-ray physics: photon properties, beam transport system, and applications (open access)

The FERMI@Elettra free-electron-laser source for coherent X-ray physics: photon properties, beam transport system, and applications

FERMI@Elettra is comprised of two free electron lasers (FELs) that will generate short pulses (tau ~;; 25 to 200 fs) of highly coherent radiation in the XUV and soft X-ray region. The use of external laser seeding together with a harmonic upshift scheme to obtain short wavelengths will give FERMI@Elettra the capability to produce high quality, longitudinal coherent photon pulses. This capability together with the possibilities of temporal synchronization to external lasers and control of the output photon polarization will open new experimental opportunities not possible with currently available FELs. Here we report on the predicted radiation coherence properties and important configuration details of the photon beam transport system. We discuss the several experimental stations that will be available during initial operations in 2011, and we give a scientific perspective on possible experiments that can exploit the critical parameters of this new light source.
Date: April 5, 2010
Creator: Allaria, Enrico; Callegari, Carlo; Cocco, Daniele; Fawley, William M.; Kiskinova, Maya; Masciovecchio, Claudio et al.
System: The UNT Digital Library
Design of An 18 MW Beam Dump for 500 GeV Electron/Positron Beams at An ILC (open access)

Design of An 18 MW Beam Dump for 500 GeV Electron/Positron Beams at An ILC

This article presents a report on the progress made in designing 18 MW water based Beam Dumps for electrons or positrons for an International Linear Collider (ILC). Multi-dimensional technology issues have to be addressed for the successful design of the Beam Dump. They include calculations of power deposition by the high energy electron/positron beam bunch trains, computational fluid dynamic analysis of turbulent water flow, mechanical design, process flow analysis, hydrogen/oxygen recombiners, handling of radioactive 7Be and 3H, design of auxiliary equipment, provisions for accident scenarios, remote window exchanger, radiation shielding, etc. The progress made to date is summarized, the current status, and also the issues still to be addressed.
Date: July 5, 2012
Creator: Amann, John; /SLAC; Arnold, Ray; /SLAC; Seryi, Andrei; /SLAC et al.
System: The UNT Digital Library
QMDS: A File System Metadata Management Service Supporting a Graph Data Model-based Query Language (open access)

QMDS: A File System Metadata Management Service Supporting a Graph Data Model-based Query Language

None
Date: December 5, 2011
Creator: Ames, S; Gokhale, M B & Maltzahn, C
System: The UNT Digital Library
Paleoclimatic implications of glacial and postglacial refugia for Pinus pumila in western Beringia (open access)

Paleoclimatic implications of glacial and postglacial refugia for Pinus pumila in western Beringia

Palynological results from Julietta Lake currently provide the most direct evidence to support the existence of a glacial refugium for Pinus pumila in mountains of southwestern Beringia. Both percentages and accumulation rates indicate the evergreen shrub survived until at least {approx}19,000 14C yr B.P. in the Upper Kolyma region. Percentage data suggest numbers dwindled into the late glaciation, whereas pollen accumulation rates point towards a more rapid demise shortly after {approx}19,000 14C yr B.P. Pinus pumila did not re-establish in any great numbers until {approx}8100 14C yr B.P., despite the local presence {approx}9800 14C yr B.P. of Larix dahurica, which shares similar summer temperature requirements. The postglacial thermal maximum (in Beringia {approx}11,000-9000 14C yr B.P.) provided Pinus pumila shrubs with equally harsh albeit different conditions for survival than those present during the LGM. Regional records indicate that in this time of maximum warmth Pinus pumila likely sheltered in a second, lower-elevation refugium. Paleoclimatic models and modern ecology suggest that shifts in the nature of seasonal transitions and not only seasonal extremes have played important roles in the history of Pinus pumila over the last {approx}21,000 14C yr B.P.
Date: February 5, 2010
Creator: Anderson, P M; Lozhkin, A V; Solomatkina, T B & Brown, T A
System: The UNT Digital Library
Terrestrial biogeochemical feedbacks in the climate system: from past to future (open access)

Terrestrial biogeochemical feedbacks in the climate system: from past to future

The terrestrial biosphere plays a major role in the regulation of atmospheric composition, and hence climate, through multiple interlinked biogeochemical cycles (BGC). Ice-core and other palaeoenvironmental records show a fast response of vegetation cover and exchanges with the atmosphere to past climate change, although the phasing of these responses reflects spatial patterning and complex interactions between individual biospheric feedbacks. Modern observations show a similar responsiveness of terrestrial biogeochemical cycles to anthropogenically-forced climate changes and air pollution, with equally complex feedbacks. For future conditions, although carbon cycle-climate interactions have been a major focus, other BGC feedbacks could be as important in modulating climate changes. The additional radiative forcing from terrestrial BGC feedbacks other than those conventionally attributed to the carbon cycle is in the range of 0.6 to 1.6 Wm{sup -2}; all taken together we estimate a possible maximum of around 3 Wm{sup -2} towards the end of the 21st century. There are large uncertainties associated with these estimates but, given that the majority of BGC feedbacks result in a positive forcing because of the fundamental link between metabolic stimulation and increasing temperature, improved quantification of these feedbacks and their incorporation in earth system models is necessary in order to develop …
Date: January 5, 2010
Creator: Arneth, A.; Harrison, S. P.; Zaehle, S.; Tsigaridis, K.; Menon, S.; Bartlein, P. J. et al.
System: The UNT Digital Library
Heavy Water Components Test Reactor Decommissioning - Major Component Removal (open access)

Heavy Water Components Test Reactor Decommissioning - Major Component Removal

The Heavy Water Components Test Reactor (HWCTR) facility (Figure 1) was built in 1961, operated from 1962 to 1964, and is located in the northwest quadrant of the Savannah River Site (SRS) approximately three miles from the site boundary. The HWCTR facility is on high, well-drained ground, about 30 meters above the water table. The HWCTR was a pressurized heavy water test reactor used to develop candidate fuel designs for heavy water power reactors. It was not a defense-related facility like the materials production reactors at SRS. The reactor was moderated with heavy water and was rated at 50 megawatts thermal power. In December of 1964, operations were terminated and the facility was placed in a standby condition as a result of the decision by the U.S. Atomic Energy Commission to redirect research and development work on heavy water power reactors to reactors cooled with organic materials. For about one year, site personnel maintained the facility in a standby status, and then retired the reactor in place. In 1965, fuel assemblies were removed, systems that contained heavy water were drained, fluid piping systems were drained, deenergized and disconnected and the spent fuel basin was drained and dried. The doors of …
Date: May 5, 2010
Creator: Austin, W. & Brinkley, D.
System: The UNT Digital Library
Applying Human Factors during the SIS Life Cycle (open access)

Applying Human Factors during the SIS Life Cycle

Safety Instrumented Systems (SIS) are widely used in U.S. Department of Energy's (DOE) nonreactor nuclear facilities for safety-critical applications. Although use of the SIS technology and computer-based digital controls, can improve performance and safety, it potentially introduces additional complexities, such as failure modes that are not readily detectable. Either automated actions or manual (operator) actions may be required to complete the safety instrumented function to place the process in a safe state or mitigate a hazard in response to an alarm or indication. DOE will issue a new standard, Application of Safety Instrumented Systems Used at DOE Nonreactor Nuclear Facilities, to provide guidance for the design, procurement, installation, testing, maintenance, operation, and quality assurance of SIS used in safety significant functions at DOE nonreactor nuclear facilities. The DOE standard focuses on utilizing the process industry consensus standard, American National Standards Institute/ International Society of Automation (ANSI/ISA) 84.00.01, Functional Safety: Safety Instrumented Systems for the Process Industry Sector, to support reliable SIS design throughout the DOE complex. SIS design must take into account human-machine interfaces and their limitations and follow good human factors engineering (HFE) practices. HFE encompasses many diverse areas (e.g., information display, user-system interaction, alarm management, operator response, control …
Date: May 5, 2010
Creator: Avery, K.
System: The UNT Digital Library
Gamma Lines without a Continuum: Thermal Models for the Fermi-LAT 130 GeV Gamma Line (open access)

Gamma Lines without a Continuum: Thermal Models for the Fermi-LAT 130 GeV Gamma Line

None
Date: April 5, 2013
Creator: Bai, Yang; /SLAC /Wisconsin U., Madison; Shelton, Jessie & U., /Yale
System: The UNT Digital Library
DDT of Aluminum/Air Mixtures in a Tunnel (open access)

DDT of Aluminum/Air Mixtures in a Tunnel

None
Date: January 5, 2012
Creator: Balakrishnan, K; Kuhl, A L & Bell, J B
System: The UNT Digital Library
Search for a Light Higgs Boson at BaBar (open access)

Search for a Light Higgs Boson at BaBar

We search for evidence of a light Higgs boson (A{sup 0}) in the radiative decays of the narrow {Upsilon}(3S) resonance: {Upsilon}(3S) {yields} {gamma}A{sup 0}, where A{sup 0} {yields} invisible or A{sup 0} {yields} {mu}{sup +}{mu}{sup -}. Such an object appears in extensions of the Standard Model, where a light CP-odd Higgs boson naturally couples strongly to b-quarks. We find no evidence for such processes in a sample of 122 x 106 {Upsilon}(3S) decays collected by the BABAR collaboration at the PEP-II B-factory, and set 90% C.L. upper limits on the product of the branching fractions {Beta}({Upsilon}(3S) {yields} {gamma}A{sup 0}) x {Beta}(A{sup 0} {yields} invisible) at (0.7-31) x 10{sup -6} in the mass range mA{sup 0} {le} 7.8 GeV, and on the product {Beta}({Upsilon}(3S) {yields} {gamma}A{sup 0}) x {Beta}(A{sup 0} {yields} {mu}{sup +}{mu}{sup -}) at (0.25-5.2) x 10{sup -6} in the mass range 0.212 {le} mA{sup 0} {le} 9.3GeV. We also set a limit on the dimuon branching fraction of the recently discovered {eta}{sub b} meson {Beta}({eta}{sub b} {yields} {mu}{sup +}{mu}{sup -}) < 0.8% at 90% C.L. The results are preliminary.
Date: December 5, 2011
Creator: Banerjee, Swagato
System: The UNT Digital Library
Re-architecting TEIMS Web-based Legacy Applications Using the Model View Controller Paradigm (open access)

Re-architecting TEIMS Web-based Legacy Applications Using the Model View Controller Paradigm

None
Date: September 5, 2012
Creator: Barbosa, E & Laguna, G W
System: The UNT Digital Library
Novel Six-Quark Hidden-Color Dibaryon States in QCD (open access)

Novel Six-Quark Hidden-Color Dibaryon States in QCD

None
Date: September 5, 2013
Creator: Bashkanov, M.; Brodsky, S.J. & Clement, H.
System: The UNT Digital Library
Top-Off Injection and Higher Currents at the Stanford Synchrotron Radiation Lightsource (open access)

Top-Off Injection and Higher Currents at the Stanford Synchrotron Radiation Lightsource

The Stanford Synchrotron Radiation Lightsource (SSRL) at the SLAC National Accelerator Laboratory is a 234 m circumference storage ring for 3 GeV electrons with its synchrotron radiation serving currently 13 beamlines with about 27 experimental stations. It operated for long time with 100 mA peak current provided by usually three injections per day. In July 2009, the maximum beam current was raised to 200 mA. Over the period from June 2009 to March 2010, Top-Off operation started at every beamline. Top-Off, i.e., the injection of electrons into the storage ring with injection stoppers open, is necessary for SSRL to reach its design current of 500 mA. In the future, the maximal power of the injection current will also soon be raised from currently 1.5 W to 5 W. The Radiation Protection Department at SLAC worked with SSRL on the specifications for the safety systems for operation with Top-Off injection and higher beam currents.
Date: April 5, 2011
Creator: Bauer, Johannes M.; Liu, James C.; Prinz, Alyssa A. & Rokni, Sayed H.
System: The UNT Digital Library