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Edmonds et al. Reply (open access)

Edmonds et al. Reply

This article is a response to an article by M. Adell et al. [Phy. Rev. Lett. 94, 139701 (2005)] about semiconductor-based spintronics research.
Date: April 8, 2005
Creator: Edmonds, Kevin; Boguslawski, Piotr; Wang, K. Y.; Campion, Richard Paul; Novikov, Sergei; Farley, N. R. S. et al.
System: The UNT Digital Library
Erratum: First-Principles Theory of Correlated Transport through Nanojunctions [Phys. Rev. Lett. 94, 116802 (2005)] (open access)

Erratum: First-Principles Theory of Correlated Transport through Nanojunctions [Phys. Rev. Lett. 94, 116802 (2005)]

This article provides the correction of an equation that was misprinted in Physical Review Letters 94, 116802 (2005).
Date: May 6, 2005
Creator: Ferretti, A.; Calzolari, Arrigo; Di Felice, Rosa; Manghi, Franca; Caldas, Marilia J.; Buongiorno Nardelli, Marco et al.
System: The UNT Digital Library
Dissociation of Water on Defective Carbon Substrates (open access)

Dissociation of Water on Defective Carbon Substrates

Article on the dissociation of water on defective carbon substrates.
Date: September 23, 2005
Creator: Kostov, Milen; Santiso, Erik; George, A. M.; Gubbins, Keith E. & Buongiorno Nardelli, Marco
System: The UNT Digital Library
First-Principles Theory of Correlated Transport through Nanojunctions (open access)

First-Principles Theory of Correlated Transport through Nanojunctions

Article on the first-principles theory of correlated transport through nanojunctions.
Date: March 25, 2005
Creator: Ferretti, A.; Calzolari, Arrigo; Di Felice, R.; Manghi, F.; Caldas, Marilia J.; Buongiorno Nardelli, Marco et al.
System: The UNT Digital Library
Band Structure and Quantum Conductance of Nanostructures from Maximally Localized Wannier Functions: The Case of Functionalized Carbon Nanotubes (open access)

Band Structure and Quantum Conductance of Nanostructures from Maximally Localized Wannier Functions: The Case of Functionalized Carbon Nanotubes

Article on band structure and quantum conductance of nanostructures from maximally localized Wannier functions.
Date: August 12, 2005
Creator: Lee, Young-Su; Buongiorno Nardelli, Marco & Marzari, Nicola
System: The UNT Digital Library
Collective polarization effects in β-polyvinylidene fluoride and its copolymers with tri- and tetrafluoroethylene (open access)

Collective polarization effects in β-polyvinylidene fluoride and its copolymers with tri- and tetrafluoroethylene

Article on collective polarization effects in β-polyvinylidene fluoride and its copolymers with tri- and tetrafluoroethylene.
Date: September 23, 2005
Creator: Nakhmanson, Serge M.; Buongiorno Nardelli, Marco & Bernholc, Jerry
System: The UNT Digital Library
Marie Jeanne Riccoboni's Lettres d'Élisabeth Sophie de Vallière: A Feminist Reading (open access)

Marie Jeanne Riccoboni's Lettres d'Élisabeth Sophie de Vallière: A Feminist Reading

Article on Marie Jeanne Riccoboni's 'Lettres d'Élisabeth Sophie de Vallière' and writing in the female voice.
Date: 2005
Creator: Kaplan, Marijn S.
System: The UNT Digital Library
(Substitute) Motherhood in Two Novels by Marie Jeanne Riccoboni (open access)

(Substitute) Motherhood in Two Novels by Marie Jeanne Riccoboni

Article on two novels by author Marie Jeanne Riccoboni, 'Histoire d'Ernestine,' published in 1765, and 'Lettres d'Elisabeth Sophie de Vallière à Louise Hortence de Canteleu, son amie,' published in 1772.
Date: 2005
Creator: Kaplan, Marijn S.
System: The UNT Digital Library
Perceptions of Youth Obesity Among Physical Educators (open access)

Perceptions of Youth Obesity Among Physical Educators

This article discusses perceptions of youth obesity among physical educators.
Date: 2005
Creator: Greenleaf, Christy & Abels, Karen Weiller
System: The UNT Digital Library
Self-Objectification Among Physically Active Women (open access)

Self-Objectification Among Physically Active Women

This article discusses self-objectification among physically active women.
Date: January 2005
Creator: Greenleaf, Christy
System: The UNT Digital Library
Correlation Function and Generalized Master Equation of Arbitrary Age (open access)

Correlation Function and Generalized Master Equation of Arbitrary Age

Article discussing research on correlation function and generalized master equation of arbitrary age.
Date: June 10, 2005
Creator: Allegrini, Paolo; Aquino, Gerardo; Grigolini, Paolo; Palatella, Luigi; Rosa, Angelo & West, Bruce J.
System: The UNT Digital Library
Transmission Electron Microscopy Study of Nonpolar a-Plane GaNGrown by Pendeo-Epitaxy on (112_0) 4H-SiC (open access)

Transmission Electron Microscopy Study of Nonpolar a-Plane GaNGrown by Pendeo-Epitaxy on (112_0) 4H-SiC

Pendeo-epitaxy has been applied to nonpolar a-plane GaN layers in order to observe if such process will lead to defect reduction in comparison with direct growth on this plane. Uncoalesced and coalesced a-plane GaN layers with thicknesses 2{micro}m and 12{micro}m, respectively have been studied by conventional and high resolution electron microscopy. The following structural defects have been observed in pendeo-epitaxial layers: (1) basal stacking faults, (2) threading dislocations and (3) prismatic stacking faults. Drastic decrease of threading dislocation density and stacking faults have been observed in 'wing' areas with respect to 'seed' areas. Cross-section images reveal cracks and voids at the areas where two coalesced wings meet each other. High resolution electron microscopy shows that the majority of stacking faults are low-energy planar defects of the types I{sub 1}, I{sub 2} and I{sub 3}. The I{sub 3} type basal stacking fault, predicted theoretically, has been observed experimentally for the first time.
Date: March 10, 2005
Creator: Zakharov, D. N.; Liliental-Weber, Z.; Wagner, B.; Reitmeier, Z. J.; Preble, E. A. & Davis, R. F.
System: The UNT Digital Library
A Chemical Kinetic Modeling Study of the Effects of Oxygenated Hydrocarbons on Soot Emissions from Diesel Engines (open access)

A Chemical Kinetic Modeling Study of the Effects of Oxygenated Hydrocarbons on Soot Emissions from Diesel Engines

A detailed chemical kinetic modeling approach is used to examine the phenomenon of suppression of sooting in diesel engines by addition of oxygenated hydrocarbon species to the fuel. This suppression, which has been observed experimentally for a few years, is explained kinetically as a reduction in concentrations of soot precursors present in the hot products of a fuel-rich diesel ignition zone when oxygenates are included. Oxygenates decrease the overall equivalence ratio of the igniting mixture, producing higher ignition temperatures and more radical species to consume more soot precursor species, leading to lower soot production. The kinetic model is also used to show how different oxygenates, ester structures in particular, can have different soot-suppression efficiencies due to differences in molecular structure of the oxygenated species.
Date: November 14, 2005
Creator: Westbrook, C K; Pitz, W J & Curran, H J
System: The UNT Digital Library
MODEL-BASED HYDROACOUSTIC BLOCKAGE ASSESSMENT AND DEVELOPMENT OF AN EXPLOSIVE SOURCE DATABASE (open access)

MODEL-BASED HYDROACOUSTIC BLOCKAGE ASSESSMENT AND DEVELOPMENT OF AN EXPLOSIVE SOURCE DATABASE

We are continuing the development of the Hydroacoustic Blockage Assessment Tool (HABAT) which is designed for use by analysts to predict which hydroacoustic monitoring stations can be used in discrimination analysis for any particular event. The research involves two approaches (1) model-based assessment of blockage, and (2) ground-truth data-based assessment of blockage. The tool presents the analyst with a map of the world, and plots raypath blockages from stations to sources. The analyst inputs source locations and blockage criteria, and the tool returns a list of blockage status from all source locations to all hydroacoustic stations. We are currently using the tool in an assessment of blockage criteria for simple direct-path arrivals. Hydroacoustic data, predominantly from earthquake sources, are read in and assessed for blockage at all available stations. Several measures are taken. First, can the event be observed at a station above background noise? Second, can we establish backazimuth from the station to the source. Third, how large is the decibel drop at one station relative to other stations. These observational results are then compared with model estimates to identify the best set of blockage criteria and used to create a set of blockage maps for each station. The …
Date: July 11, 2005
Creator: Matzel, E; Ramirez, A & Harben, P
System: The UNT Digital Library
Using Contingent Valuation to Explore Willingness to Pay forRenewable Energy: A Comparison of Collective and Voluntary PaymentVehicles (open access)
Relationships between walking and percentiles of adiposity inolder and younger men (open access)

Relationships between walking and percentiles of adiposity inolder and younger men

To assess the relationship of weekly walking distance to percentiles of adiposity in elders (age {ge} 75 years), seniors (55 {le} age <75 years), middle-age men (35 {le} age <55 years), and younger men (18 {le} age <35 years old). Cross-sectional analyses of baseline questionnaires from 7,082 male participants of the National Walkers Health Study. The walkers BMIs were inversely and significantly associated with walking distance (kg/m{sup 2} per km/wk) in elders (slope {+-} SE: -0.032 {+-} 0.008), seniors (-0.045 {+-} 0.005), and middle-aged men (-0.037 {+-} 0.007), as were their waist circumferences (-0.091 {+-} 0.025, -0.045 {+-} 0.005, and -0.091 {+-} 0.015 cm per km/wk, respectively), and these slopes remained significant when adjusted statistically for reported weekly servings of meat, fish, fruit, and alcohol. The declines in BMI associated with walking distance were greater at the higher than lower percentiles of the BMI distribution. Specifically, compared to the decline at the 10th BMI percentile, the decline in BMI at the 90th percentile was 5.1-fold greater in elders, 5.9-fold greater in seniors, and 6.7-fold greater in middle-age men. The declines in waist circumference associated with walking distance were also greater among men with broader waistlines. Exercise-induced weight loss (or self-selection) …
Date: June 1, 2005
Creator: Williams, Paul T.
System: The UNT Digital Library
Evaluation of production samples of the scintillators LaBr3:Ce and LaCl3:Ce (open access)

Evaluation of production samples of the scintillators LaBr3:Ce and LaCl3:Ce

We report on the evaluation of the performance of two recently developed scintillator materials, LaCl{sub 3}:Ce and LaBr{sub 3}:Ce, at the task of gamma ray spectroscopy. Their performance is compared to a standard scintillator used for gamma ray spectroscopy--a 25 mm diameter 25 mm tall cylinder of NaI:Tl. We measure the pulse height, energy resolution, and full-energy efficiency of production LaBr{sub 3}:Ce and LaCl{sub 3}:Ce scintillation crystals of different sizes and geometries for a variety of gamma-ray energies. Using production rather than specially selected crystals will establish whether immediate large-scale use is feasible. The crystal is excited by gamma rays from one of six isotopic sources ({sup 125}I, {sup 241}Am, {sup 57}Co, {sup 22}Na, {sup 137}Cs, and {sup 60}Co) placed 15 cm away from the scintillator. Our measurements show that both LaCl{sub 3} and LaBr{sub 3} outperform NaI:Tl in almost all cases. They outperform NaI:Tl at all energies for the photopeak fraction and counting rate measurements, and for energy resolution at higher energies (above 200 keV for LaCl{sub 3} and 75 keV for LaBr{sub 3}). The performance of production crystals is excellent and these scintillators should be considered for immediate use in systems where stopping power and energy resolution are …
Date: September 15, 2005
Creator: Choong, Woon-Seng; Derenzo, Stephen E. & Moses, William W.
System: The UNT Digital Library
A short model excitation of an asymmetric force free superconducting transmission line magnet (open access)

A short model excitation of an asymmetric force free superconducting transmission line magnet

A short model of asymmetric force free magnet with single beam aperture was tested at Fermilab together with the excitation test of VLHC transmission line magnet. The design concept of asymmetric force free superconducting magnet was verified by the test. The testing reached up to 104 kA current and no indication of force imbalance was observed. Since the model magnet length was only 10cm, A 0.75m model was constructed and tested at KEK with low current to ensure the validity of the design. The cool down and the excitation at KEK were also successful finding very small thermal contraction of the conductor and reasonable field homogeneity.
Date: September 1, 2005
Creator: Wake, M.; Sato, H.; Carcagno, R.; Foster, W.; Hays, S.; Kashikhin, V. et al.
System: The UNT Digital Library
Strangeness at SIS energies (open access)

Strangeness at SIS energies

In this contribution the authors discuss the physics of strange hadrons in low energy ({approx_equal} 1-2 AGeV) heavy ion collision. In this energy range the relevant strange particle are the kaons and anti-kaons. The most interesting aspect concerning these particles are so called in-medium modifications. They will attempt to review the current status of understanding of these in medium modifications. In addition they briefly discuss other issues related with kaon production, such as the nuclear equation of state and chemical equilibrium.
Date: September 28, 2005
Creator: Koch, Volker
System: The UNT Digital Library
Benchmarking and Self-Assessment in the Wine Industry (open access)

Benchmarking and Self-Assessment in the Wine Industry

Not all industrial facilities have the staff or theopportunity to perform a detailed audit of their operations. The lack ofknowledge of energy efficiency opportunities provides an importantbarrier to improving efficiency. Benchmarking programs in the U.S. andabroad have shown to improve knowledge of the energy performance ofindustrial facilities and buildings and to fuel energy managementpractices. Benchmarking provides a fair way to compare the energyintensity of plants, while accounting for structural differences (e.g.,the mix of products produced, climate conditions) between differentfacilities. In California, the winemaking industry is not only one of theeconomic pillars of the economy; it is also a large energy consumer, witha considerable potential for energy-efficiency improvement. LawrenceBerkeley National Laboratory and Fetzer Vineyards developed the firstbenchmarking tool for the California wine industry called "BEST(Benchmarking and Energy and water Savings Tool) Winery". BEST Wineryenables a winery to compare its energy efficiency to a best practicereference winery. Besides overall performance, the tool enables the userto evaluate the impact of implementing efficiency measures. The toolfacilitates strategic planning of efficiency measures, based on theestimated impact of the measures, their costs and savings. The tool willraise awareness of current energy intensities and offer an efficient wayto evaluate the impact of future efficiency measures.
Date: December 1, 2005
Creator: Galitsky, Christina; Radspieler, Anthony; Worrell, Ernst; Healy,Patrick & Zechiel, Susanne
System: The UNT Digital Library
Pulse Radiolysis of Aqueous Thiocyanate Solution (open access)

Pulse Radiolysis of Aqueous Thiocyanate Solution

The pulse radiolysis of N2O saturated aqueous solutions of KSCN was studied under neutral pH conditions. The observed optical absorption spectrum of the SCN• radical in solution is more complex than previously reported, but it is in good agreement with that measured in the gas phase. Kinetic traces at 330 nm and 472 nm corresponding to SCN• and (SCN)2•¯, respectively, were fit using a Monte Carlo simulation kinetic model. The rate coefficient for the oxidation of SCN¯ ions by OH radicals, an important reaction used in competition kinetics measurements, was found to be 1.4 ± 0.1 x 1010 M-1 s-1, about 30 % higher than the normally accepted value. A detailed discussion of the reaction mechanism is presented.
Date: January 13, 2005
Creator: Milosavljevic, Bratoljub H. & LaVerne, Jay A.
System: The UNT Digital Library
Double Gap Alfvén Eigenmodes: Revisiting Eigenmodes Interaction with the Alfvén Continuum (open access)

Double Gap Alfvén Eigenmodes: Revisiting Eigenmodes Interaction with the Alfvén Continuum

A new type of global shear Alfvén Eigenmode is found in tokamak plasmas where the mode localization is in the region intersecting the Alfvén continuum. The eigenmode is formed by the coupling of two solutions from two adjacent gaps (akin to potential wells) in the shear Alfvén continuum. For tokamak plasmas with reversed magnetic shear it is shown that the toroidiciy-induced solution tunnels through the continuum to match the ellipticity-induced Alfvén eigenmode (TAE and EAE, respectively) so that the resulting solution is continuous at the point of resonance with the continuum. The existence of these Double Gap Alfvén Eigenmodes (DGAEs) allows for potentially new ways of coupling edge fields to the plasma core in conditions where the core region is conventionally considered inaccessible. Implications include new approaches to heating and current drive in fusion plasmas as well as its possible use as core diagnostic in burning plasmas.
Date: December 1, 2005
Creator: Gorelenkov, N. N.
System: The UNT Digital Library
Strangelet Search at the BNL Relativistic Heavy Ion Collider (open access)

Strangelet Search at the BNL Relativistic Heavy Ion Collider

We have searched for strangelets in a triggered sample of 61 million central (top 4percent) Au+Au collisions at sqrt sNN = 200 GeV near beam rapidities at the STAR solenoidal tracker detector at the BNL Relativistic Heavy Ion Collider. We have sensitivity to metastable strangelets with lifetimes of order>_0.1 ns, in contrast to limits over ten times longer in BNL Alternating Gradient Synchrotron (AGS) studies and longer still at the CERN Super Proton Synchrotron (SPS). Upper limits of a few 10-6 to 10-7 per central Au+Au collision are set for strangelets with mass>~;;30 GeV/c2.
Date: November 27, 2005
Creator: Ritter, Ha
System: The UNT Digital Library
Leaching of FGD Byproducts Using a CSTX (open access)

Leaching of FGD Byproducts Using a CSTX

Leaching studies of coal utilization byproducts (CUB) are often performed to determine the compatibility of the material in a particular end-use or disposal environment. Typically, these studies are conducted using either a batch or a fixed-bed column technique. Fixed-bed columns offer the advantage of a continuous flow of effluent that provides elution profiles with changing elution volume and pH. Unfortunately, clogs can form in fixed-bed leaching columns, either because of cementitious properties of the material itself, such as is seen for fluidized bed combustion (FBC) fly ash, or because of precipitate formation, such as can occur when a high-calcium ash is subjected to sulfate-containing leachates. Also, very fine-grained materials, such as gypsum, do not provide sufficient permeability for study in a fixed-bed column. A continuous, stirred-tank extractor (CSTX) is being used as an alternative technique that can provide the elution profile of column leaching but without the low permeability problems. The CSTX has been successfully employed in the leaching of flue gas desulfurization products that would not be sufficiently permeable under traditional column leaching conditions. The results indicate that the leaching behavior depends on a number of factors, including (but not limited to) solubility and neutralization capacity of the mineral …
Date: September 1, 2005
Creator: Kairies, C.L.; Schroeder, K.T. & Cardone, C.R.
System: The UNT Digital Library