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First-Principles Theory of Correlated Transport through Nanojunctions

Description: 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.
Partner: UNT College of Arts and Sciences
open access

Dynamic Conductance of Carbon Nanotubes

Description: Article on dynamic conductance of carbon nanotubes.
Date: March 27, 2000
Creator: Roland, Christopher; Buongiorno Nardelli, Marco; Wang, Jian & Guo, Hong
Partner: UNT College of Arts and Sciences
open access

Oxidation of alloys targeted for advanced steam turbines

Description: Ultra supercritical (USC) power plants offer the promise of higher efficiencies and lower emissions. Current goals of the U.S. Department of Energy’s Advanced Power Systems Initiatives include coal generation at 60% efficiency, which would require steam temperatures of up to 760°C. This research examines the steamside oxidation of alloys for use in USC systems, with emphasis placed on applications in high- and intermediate-pressure turbines.
Date: March 12, 2006
Creator: Holcomb, G. R.; Covino, B. S., Jr.; Bullard, S. J.; Ziomek-Moroz, M. & Alman, D. E.
Partner: UNT Libraries Government Documents Department
open access

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

Description: 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) pris… more
Date: March 10, 2005
Creator: Zakharov, D. N.; Liliental-Weber, Z.; Wagner, B.; Reitmeier, Z. J.; Preble, E. A. & Davis, R. F.
Partner: UNT Libraries Government Documents Department
open access

Differentiating neutrino models on the basis of $\theta_{13}$ and lepton flavor violation

Description: The authors show how models of neutrino masses and mixings can be differentiated on the basis of their predictions for {theta}{sub 13} and lepton flavor violation in radiative charged lepton decays and {mu} - e conversion. They illustrate the lepton flavor violation results for five predictive SO(10) SUSY GUT models and point out the relative importance of their heavy right-handed neutrino mass spectra and {theta}{sub 13} predictions.
Date: March 1, 2008
Creator: Albright, Carl H.
Partner: UNT Libraries Government Documents Department
open access

The U.S. Department of Energy's Aerial Measuring System (AMS)

Description: For nearly 40 years, aerial radiological search and survey missions have been performed by the United States Department of Energy's (USDOE) Remote Sensing Laboratory (RSL). Originally created in 1967 as Aerial Measurement Operations (AMO), the AMS mission has expanded to include acquiring baseline measurements, performing periodic area monitoring, and responding to radiological emergencies. In an accident scenario, AMS fixed-wing and/or rotary-wing systems can be deployed to map radiological de… more
Date: March 1, 2008
Creator: Marianno, Craig
Partner: UNT Libraries Government Documents Department
open access

Book Review Geostatistical Analysis of Compositional Data

Description: Compositional data are represented as vector variables with individual vector components ranging between zero and a positive maximum value representing a constant sum constraint, usually unity (or 100 percent). The earth sciences are flooded with spatial distributions of compositional data, such as concentrations of major ion constituents in natural waters (e.g. mole, mass, or volume fractions), mineral percentages, ore grades, or proportions of mutually exclusive categories (e.g. a water-oil-r… more
Date: March 26, 2007
Creator: Carle, S F
Partner: UNT Libraries Government Documents Department
open access

Evolution of the Surface Science of Catalysis from Single Crystals to Metal Nanoparticles under Pressure

Description: Vacuum studies of metal single crystal surfaces using electron and molecular beam scattering revealed that the surface atoms relocate when the surface is clean (reconstruction) and when it is covered by adsorbates (adsorbate induced restructuring). It was also discovered that atomic steps and other low coordination surface sites are active for breaking chemical bonds (H-H, O=O, C-H, C=O and C-C) with high reaction probability. Investigations at high reactant pressures using sum frequency genera… more
Date: March 6, 2008
Creator: Somorjai, Gabor A. & Park, Jeong Y.
Partner: UNT Libraries Government Documents Department
open access

A High-Flux, Flexible Membrane with Parylene-encapsulated Carbon Nanotubes

Description: We present fabrication and characterization of a membrane based on carbon nanotubes (CNTs) and parylene. Carbon nanotubes have shown orders of magnitude enhancement in gas and water permeability compared to estimates generated by conventional theories [1, 2]. Large area membranes that exhibit flux enhancement characteristics of carbon nanotubes may provide an economical solution to a variety of technologies including water desalination [3] and gas sequestration [4]. We report a novel method of … more
Date: March 14, 2008
Creator: Park, H. G.; In, J.; Kim, S.; Fornasiero, F.; Holt, J. K.; Grigoropoulos, C. P. et al.
Partner: UNT Libraries Government Documents Department
open access

Eclipsing binary stars in the Large and Small Magellanic Clouds from the MACHO project: The Sample

Description: We present a new sample of 4634 eclipsing binary stars in the Large Magellanic Cloud (LMC), expanding on a previous sample of 611 objects and a new sample of 1509 eclipsing binary stars in the Small Magellanic Cloud (SMC), that were identified in the light curve database of the MACHO project. We perform a cross correlation with the OGLE-II LMC sample, finding 1236 matches. A cross correlation with the OGLE-II SMC sample finds 698 matches. We then compare the LMC subsamples corresponding to cent… more
Date: March 29, 2007
Creator: Faccioli, L.; Alcock, C.; Cook, K.; Prochter, G.; Protopapas, P. & Syphers, D.
Partner: UNT Libraries Government Documents Department
open access

Separation of Yeast Cells from MS2 Viruses Using Acoustic Radiation Force

Description: We report a rapid and robust separation of Saccharomyces cerevisiae and MS2 bacteriophage using acoustic focusing in a microfluidic device. A piezoelectric transducer (PZT) generates acoustic standing waves in the microchannel. These standing waves induce acoustic radiation force fields that direct microparticles towards the nodes (i.e., pressure minima) or the anti-nodes (i.e., pressure maxima) of the standing waves depending on the relative compressidensity between the particle and the suspen… more
Date: March 27, 2008
Creator: Jung, B.; Fisher, K.; Ness, K.; Rose, K. A. & Mariella, R. P., Jr.
Partner: UNT Libraries Government Documents Department
open access

Vibrational Spectroscopy and X-ray Diffraction of Cd(OH)2 to 28GPa at 300 K

Description: We report Raman and infrared absorption spectroscopy alongwith X-ray diffraction for brucite-type beta-Cd(OH)2 to 28 GPa at 300 K.The OH-stretching modes soften with pressure and disappear at 21 GPa withtheir widths increasing rapidly above 5 GPa, consistent with a gradualdisordering of the H sublattice at 5 20 GPa similar to that previouslyobserved for Co(OH)2.Asymmetry in the peak shapes of the OH-stretchingmodes suggests the existence of diverse disordered sitesfor H atoms inCd(OH)2 under pr… more
Date: March 20, 2006
Creator: Shim, Sang-Heon; Rekhi, Sandeep; Martin, Michael C. & Jeanloz,Raymond
Partner: UNT Libraries Government Documents Department
open access

The Surface Wave Magnitude for the 9 October 2006 North Korean Nuclear Explosion

Description: Surface waves were generated by the North Korean nuclear explosion of 9 October 2006 and recorded at epicentral distances up to 34 degrees, from which we estimated a surface wave magnitude (M{sub s}) of 2.94 with an interstation standard deviation of 0.17 magnitude units. The International Data Centre estimated a body wave magnitude (m{sub b}) of 4.1. This is the only explosion we have analyzed that was not easily screened as an explosion based on the differences between the M{sub s} and m{sub … more
Date: March 11, 2008
Creator: Bonner, J; Herrmann, R; Harkrider, D & Pasyanos, M
Partner: UNT Libraries Government Documents Department
open access

Digitral Down Conversion Technology for Tevatron Beam Line Tuner at FNAL

Description: Fermilab is presently in Run II collider operations and is developing instrumentation to improve luminosity. Improving the orbit matching between accelerator components using a Beam Line Tuner (BLT) can improve the luminosity. Digital Down Conversion (DDC) has been proposed as a method for making more accurate beam position measurements. Fermilab has implemented a BLT system using a DDC technique to measure orbit oscillations during injections from the Main Injector to the Tevatron. The output … more
Date: March 17, 2008
Creator: Schappert, W.; Lorman, E.; Scarpine, V.; Ross, M.C.; Sebek, J.; Straumann, T. et al.
Partner: UNT Libraries Government Documents Department
open access

InN Nanorods Grown on Different Planes of Al2O3

Description: No Description Available.
Date: March 10, 2007
Creator: Liliental-Weber, Z.; Park, H.J.; Mangum, J.; Anderson, T. & Kryliouk, O.
Partner: UNT Libraries Government Documents Department
open access

Update on Mechanical Analysis of Monolithic Fuel Plates

Description: Results on the relative bond strength of the fuel-clad interface in monolithic fuel plates have been presented at previous RRFM conferences. An understanding of mechanical properties of the fuel, cladding, and fuel / cladding interface has been identified as an important area of investigation and quantification for qualification of monolithic fuel forms. Significant progress has been made in the area of mechanical analysis of the monolithic fuel plates, including mechanical property determinati… more
Date: March 1, 2008
Creator: Burkes, D. E.; Rice, F. J.; Jue, J.-F. & Hallinan, N. P.
Partner: UNT Libraries Government Documents Department
open access

Citric Acid-Modified Fenton's Reaction for the Oxidation of Chlorinated Ethylenes in Soil Solution Systems

Description: Fenton's reagent, a solution of hydrogen peroxide and ferrous iron catalyst, is used for an in-situ chemical oxidation of organic contaminants. Sulfuric acid is commonly used to create an acidic condition needed for catalytic oxidation. Fenton's reaction often involves pressure buildup and precipitation of reaction products, which can cause safety hazards and diminish efficiency. We selected citric acid, a food-grade substance, as an acidifying agent to evaluate its efficiencies for organic con… more
Date: March 15, 2008
Creator: Seol, Yongkoo & Javandel, Iraj
Partner: UNT Libraries Government Documents Department
open access

Application of a pilot control banding tool for risk level assessment and control of nanoparticle exposures

Description: Control Banding (CB) strategies offer simplified solutions for controlling worker exposures to constituents that are found in the workplace in the absence of firm toxicological and exposure data. These strategies may be particularly useful in nanotechnology applications, considering the overwhelming level of uncertainty over what nanomaterials and nanotechnologies present as potential work-related health risks, what about these materials might lead to adverse toxicological activity, how risk re… more
Date: March 3, 2008
Creator: Paik, S Y; Zalk, D M & Swuste, P
Partner: UNT Libraries Government Documents Department
open access

FRMAC Mission Analysis: What is it, and why is it useful?

Description: In 2002, the Director of the U.S. Department of Energy's (DOE's) National Nuclear Security Administration, Division of Emergency Response, requested a team of DOE scientists, considered experts in the field of radiological consequence management, assemble and construct a mission analysis upon which the DOE could build its response program and plan for future requirements. The team developed five scenarios upon which to build the data quality objectives (DQOs) that they considered necessary to e… more
Date: March 1, 2008
Creator: Hopkins, Rhonda
Partner: UNT Libraries Government Documents Department
open access

Basalt weathering rates on Earth and the duration of liquid water on the plains of Gusev Crater, Mars

Description: Where Martian rocks have been exposed to liquid water, chemistry versus depth profiles could elucidate both Martian climate history and potential for life. The persistence of primary minerals in weathered profiles constrains the exposure time to liquid water: on Earth, mineral persistence times range from {approx}10 ka (olivine) to {approx}250 ka (glass) to {approx}1Ma (pyroxene) to {approx}5Ma (plagioclase). Such persistence times suggest mineral persistence minima on Mars. However, Martian so… more
Date: March 15, 2008
Creator: Steefel, Carl; Hausrath, E. M.; Navarre-Sitchler, A. K.; Sak, P. B.; Steefel, C. & Brantley, S. L.
Partner: UNT Libraries Government Documents Department
open access

Cfd Modeling Analysis of Mechanical Draft Cooling Tower

Description: Industrial processes use mechanical draft cooling towers (MDCT's) to dissipate waste heat by transferring heat from water to air via evaporative cooling, which causes air humidification. The Savannah River Site (SRS) has a MDCT consisting of four independent compartments called cells. Each cell has its own fan to help maximize heat transfer between ambient air and circulated water. The primary objective of the work is to conduct a parametric study for cooling tower performance under different f… more
Date: March 3, 2008
Creator: Lee, S.; Alfred Garrett, A.; James02 Bollinger, J. & Larry Koffman, L.
Partner: UNT Libraries Government Documents Department
open access

Comparative Genome Analysis in the Integrated Microbial Genomes (IMG) System

Description: Comparative genome analysis is critical for the effectiveexploration of a rapidly growing number of complete and draft sequencesfor microbial genomes. The Integrated Microbial Genomes (IMG) system(img.jgi.doe.gov) has been developed as a community resource thatprovides support for comparative analysis of microbial genomes in anintegrated context. IMG allows users to navigate the multidimensionalmicrobial genome data space and focus their analysis on a subset ofgenes, genomes, and functions of i… more
Date: March 1, 2006
Creator: Kyrpides, Nikos C. & Markowitz, Victor M.
Partner: UNT Libraries Government Documents Department
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