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Progress in Photovoltaic Components and Systems

Description: The Photovoltaic Manufacturing Research and Development project is a government/industry partnership between the US Department of Energy and members of the US photovoltaic (TV) industry. The purpose of the project is to work with industry to improve manufacturing processes, reduce manufacturing costs, and improve the performance of PV products. This project is conducted through phased solicitations with industry participants selected through a competitive evaluation process. Starting in 1995, t… more
Date: July 15, 2000
Creator: Thomas, H.; Kroposki, B.; Witt, C. & Bower, Ward I.
Partner: UNT Libraries Government Documents Department
open access

Protein-Nanocrystal Conjugates Support a Single Filament Polymerization Model in R1 Plasmid Segregation

Description: To ensure inheritance by daughter cells, many low-copy number bacterial plasmids, including the R1 drug-resistance plasmid, encode their own DNA segregation systems. The par operon of plasmid R1 directs construction of a simple spindle structure that converts free energy of polymerization of an actin-like protein, ParM, into work required to move sister plasmids to opposite poles of rod-shaped cells. The structures of individual components have been solved, but little is known about the ultrast… more
Date: July 15, 2008
Creator: Choi, Charina L.; Claridge, Shelley A.; Garner, Ethan C.; Alivisatos, A. Paul & Mullins, R. Dyche
Partner: UNT Libraries Government Documents Department
open access

THERMOPHYSICAL PROPERTIES OF NANOPARTICLE-ENHANCED IONIC LIQUIDS HEAT TRANSFER FLUIDS

Description: An experimental investigation was completed on nanoparticle enhanced ionic liquid heat transfer fluids as an alternative to conventional organic based heat transfer fluids (HTFs). These nanoparticle-based HTFs have the potential to deliver higher thermal conductivity than the base fluid without a significant increase in viscosity at elevated temperatures. The effect of nanoparticle morphology and chemistry on thermophysical properties was examined. Whisker shaped nanomaterials were found to hav… more
Date: April 15, 2013
Creator: Fox, E.
Partner: UNT Libraries Government Documents Department
open access

Spatiotemporal characterization of ionizing radiation induced DNA damage foci and their relation to chromatin organization

Description: DNA damage sensing proteins have been shown to localize to the sites of DSB within seconds to minutes following ionizing radiation (IR) exposure, resulting in the formation of microscopically visible nuclear domains referred to as radiation-induced foci (RIF). This review characterizes the spatio-temporal properties of RIF at physiological doses, minutes to hours following exposure to ionizing radiation, and it proposes a model describing RIF formation and resolution as a function of radiation … more
Date: September 15, 2009
Creator: Costes, Sylvain V; Chiolo, Irene; Pluth, Janice M.; Barcellos-Hoff, Mary Helen & Jakob, Burkhard
Partner: UNT Libraries Government Documents Department
open access

Status of the Daya Bay Reactor Neutrino Oscillation Experiment

Description: The last unknown neutrino mixing angle theta_13 is one of the fundamental parameters of nature; it is also a crucial parameter for determining the sensitivity of future long-baseline experiments aimed to study CP violation in the neutrino sector. Daya Bay is a reactor neutrino oscillation experiment designed to achieve a sensitivity on the value of sin^2(2*theta_13) to better than 0.01 at 90percent CL. The experiment consists of multiple identical detectors placed underground at different basel… more
Date: December 15, 2010
Creator: Collaboration, Daya Bay & Lin, Cheng-Ju Stephen
Partner: UNT Libraries Government Documents Department
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On the Questions of the Nuclear Level Density and the e1 Photon Strength Functions

Description: New results were derived from average level spacings of neutron resonances for the spin dispersion parameter of the nuclear level density, which demonstrated the influence of shell effects, as well as the interplay of nucleon pairing correlations for nuclei in the mass range from {sup 29}Si to {sup 241}Pu. The volume and surface components of the nuclear level density parameter, as well as the shell-damping factor, were determined as, a{sub v} = 0.076 {+-} 0.009 MeV{sup {minus}1} , a{sub s} = 0… more
Date: November 15, 1999
Creator: Mughabghab, S. F. & Dunford, C. L.
Partner: UNT Libraries Government Documents Department
open access

Dipole strength functions in the actinide mass region

Description: We have calculated a number of neutron- and photon-induced reactions for the actinide nuclei /sup 232/Th, /sup 238/U, and /sup 237/Np. By fitting average resonance capture (ARC) measurements and total neutron capture data, we deduced absolute dipole strength functions for /sup 233/Th and /sup 239/U. We have found that the M1/E1 ratio is the same as in the /sup 176/Lu case, but the total transition strength was larger by about 27%. 17 refs., 4 figs., 1 tab.
Date: July 15, 1987
Creator: Gardner, D. G.; Gardner, M. A. & Hoff, R. W.
Partner: UNT Libraries Government Documents Department
open access

Electronic structure of the iron-based superconductor LaOFeP

Description: The recent discovery of superconductivity in the so-called iron-oxypnictide family of compounds has generated intense interest. The layered crystal structure with transition metal ions in planar square lattice form and the discovery of spin-density-wave order near 130K seem to hint at a strong similarity with the copper oxide superconductors. A burning current issue is the nature of the ground state of the parent compounds. Two distinct classes of theories have been put forward depending on the… more
Date: February 15, 2010
Creator: Lu, D. H.; Yi, M.; /Stanford U., Phys. Dept. /SLAC, SSRL; Mo1, S.-K.; /Stanford U., Phys. Dept. /SLAC, SSRL /LBNL, ALS; Erickson, A. S. et al.
Partner: UNT Libraries Government Documents Department
open access

Excitation and Ionization in H(1s)-H(1s) Collisions

Description: Hydrogen atom - hydrogen atom scattering is a prototype for many of the fundamental principles of atomic collisions. In this work we present an approximation to the H+H system for scattering in the intermediate energy regime of 1 to 100 keV. The approximation ignores electron exchange and two-electron excitation by assuming that one of the atoms is frozen in the 1s state. We allow for the evolution of the active electron by numerically solving the 3D Schroedinger equation. The results capture m… more
Date: July 15, 1999
Creator: Riley, Merle E. & Ritchie, A. Burke
Partner: UNT Libraries Government Documents Department
open access

Molecular Thermodynamics for Swelling of a Mesoscopic Ionomer Gelin 1:1 Salt Solutions

Description: For a microphase-separated diblock copolymer ionic gel swollen in salt solution, a molecular-thermodynamic model is based on the self-consistent field theory in the limit of strongly segregated copolymer subchains. The geometry of microdomains is described using the Milner generic wedge construction neglecting the packing frustration. Thermodynamic functions are expressed analytically for gels of lamellar, bicontinuous, cylindrical and spherical morphologies. Molecules are characterized by chai… more
Date: June 15, 2005
Creator: Victorov, Alexey; Radke, Clayton & Prausnitz,John
Partner: UNT Libraries Government Documents Department
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Pysico-chemical properties of hydrophobic ionic liquids containing1-octylpyridinium, 1-octyl-2-methylpyridinium or1-octyl-4-methylpyridinium cations

Description: This paper reports synthesis of some ionic liquids based on cations 1-octylpyridinium, 1-octyl-2-methylpyridinium or 1-octyl-4-methylpyridinium and anions dicyanamide [N(CN)2]-, bis(trifluoromethylsulfonyl)imide [Tf2N]-, bis(pentafluoroethylsulfonyl)imide [BETI]-, trifluoromethyl sulfonate [TfO]-, nonafluorobutyl sulfonate [NfO]-, tetrafluoroborate [BF4]-, trifluorophenylborate [BF3Ph]- or hexafluoroarsenate [AsF6]-. Melting points, decomposition temperatures, densities, mutual solubilities wit… more
Date: September 15, 2006
Creator: Papaiconomou, Nicolas; Salminen, Justin; Lee, Jong-Min & Prausnitz, John M.
Partner: UNT Libraries Government Documents Department
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EAGLES 1.1: A microcomputer software package for analyzing fuel efficiency of electric and gasoline vehicles

Description: As part of the U.S. Department of Energy`s electric/hybrid vehicle research program, Argonne National Laboratory has developed a computer software package called EAGLES. This paper describes the capability of the software and its many features and potential applications. EAGLES version 1.1 is an interactive microcomputer software package for the analysis of battery performance in electric-vehicle applications, or the estimation of fuel economy for a gasoline vehicle. The principal objective of … more
Date: May 15, 1994
Creator: Marr, W. M.
Partner: UNT Libraries Government Documents Department
open access

Testing high-Z QED with SuperEBIT: An estimate of the U91+ 1s two-loop Lamb shift based on a measurement of the 2s1/2 - 2p1/2 transition in U89+

Description: Starting from the results of a recent measurement of the 2s{sub 1/2}-2p{sub 1/2} transition in U{sup 89+} has been made on the SuperEBIT electron beam ion trap, which provided a determination of the 2s two-loop QED contribution, we estimate 1.27 {+-} 0.45 eV for the two-loop contribution to the 1s level in U{sup 91+}. This estimate could be improved by a factor of two or more, if the uncertainties associated with the three-photon exchange in the theoretical calculations were eliminated in the f… more
Date: July 15, 2005
Creator: Beiersdorfer, P
Partner: UNT Libraries Government Documents Department
open access

Illuminating the 1/x Moment of Parton Distribution Functions

Description: The Weisberger relation, an exact statement of the parton model, elegantly relates a high-energy physics observable, the 1/x moment of parton distribution functions, to a nonperturbative low-energy observable: the dependence of the nucleon mass on the value of the quark mass or its corresponding quark condensate. We show that contemporary fits to nucleon structure functions fail to determine this 1/x moment; however, deeply virtual Compton scattering can be described in terms of a novel F1/x(t)… more
Date: October 15, 2007
Creator: Brodsky, Stanley J.; Llanes-Estrada, Felipe J. & Szczepaniak, Adam P.
Partner: UNT Libraries Government Documents Department
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Real-structure effects: Band gaps of Mg_xZn_{1-x}O, Cd_xZn_{1-x}O, and n-type ZnO from ab-initio calculations

Description: Many-body perturbation theory is applied to compute the quasiparticle electronic structures and the optical-absorption spectra (including excitonic effects) for several transparent conducting oxides. We discuss HSE+G{sub 0}W{sub 0} results for band structures, fundamental band gaps, and effective electron masses of MgO, ZnO, CdO, SnO{sub 2}, SnO, In{sub 2}O{sub 3}, and SiO{sub 2}. The Bethe-Salpeter equation is solved to account for excitonic effects in the calculation of the frequency-dependen… more
Date: February 15, 2012
Creator: Schleife, A & Bechstedt, F
Partner: UNT Libraries Government Documents Department
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Baryon Triality And Neutrino Masses From An Anomalous FlavorU(1)

Description: We construct a concise U(1){sub X} Froggatt-Nielsen model in which baryon triality, a discrete gauge Z{sub 3}-symmetry, arises from U(1){sub X} breaking. The proton is thus stable, however, R-parity is violated. With the proper choice of U(1){sub X} charges we can obtain neutrino masses and mixings consistent with an explanation of the atmospheric and solar neutrino anomalies in terms of neutrino oscillations, with no right-handed neutrinos required. The only mass scale apart from M{sub grav} i… more
Date: August 15, 2007
Creator: Dreiner, Herbi K.; Luhn, Christoph; Murayama, Hitoshi & Thormeier,Marc
Partner: UNT Libraries Government Documents Department
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Actinide Source Term Program, position paper. Revision 1

Description: The Actinide Source Term represents the quantity of actinides that could be mobilized within WIPP brines and could migrate with the brines away from the disposal room vicinity. This document presents the various proposed methods for estimating this source term, with a particular focus on defining these methods and evaluating the defensibility of the models for mobile actinide concentrations. The conclusions reached in this document are: the 92 PA {open_quotes}expert panel{close_quotes} model fo… more
Date: November 15, 1994
Creator: Novak, C. F.; Papenguth, H. W.; Crafts, C. C. & Dhooge, N. J.
Partner: UNT Libraries Government Documents Department
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Non-Salado flow and transport position paper. Revision 1

Description: The US Department of Energy (DOE) is preparing to request the US Environmental Protection Agency (EPA) to certify compliance of the Waste Isolation Pilot Plant (WIPP) with long-term requirements of the environmental Radiation Protection Standards for Management and Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Waste (40 CFR Part 191). The DOE must also demonstrate compliance with the long-term requirements of the Land Disposal Restrictions of the Resour… more
Date: December 15, 1994
Creator: Axness, C.; Beauheim, R. & Behl, Y.
Partner: UNT Libraries Government Documents Department
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Immobilization as a route to surplus fissile materials disposition. Revision 1

Description: The safe management of surplus weapons plutonium is a very important and urgent task with profound environmental, national and international security implications. In the aftermath of the Cold War, Presidential Police Directive 13 and various analysis by renown scientific, technical and international policy organizations have brought about a focused effort within the Department of Energy to identify and implement paths forward for the long term disposition of surplus weapons usable plutonium. T… more
Date: March 15, 1996
Creator: Gray, L.W.; Kan, T. & McKibben, J.M.
Partner: UNT Libraries Government Documents Department
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Static and dynamic analyses on the MFTF-B vacuum vessel. Revision 1

Description: The Mirror Fusion Test Facility is a major magnetic fusion energy project at the Lawrence Livermore National Laboratory. An important component of this facility is the vacuum vessel, which forms the vacuum chamber. The vessel is supported on twenty-two pairs of legs that rest on reinforced concrete piers. In performing static and dynamic analyses on the vacuum vessel, we separately investigated the load distribution under gravity loads, pressure loads, electromagnetic loads, and thermal loads. … more
Date: January 15, 1984
Creator: Ng, D.S.
Partner: UNT Libraries Government Documents Department
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A parametric model for analysis of melt progression in U-A1 assemblies

Description: A computational model has been developed that calculates the thermal degradation of the reactor core of the production reactors at the Savannah River Site (SRS) under postulated severe accident conditions. This model addresses heatup and degradation of the U-Al fuel and Li-Al or U-metal target assemblies and neighboring structures. Models included are those for assembly heatup due to decay heat generation, material melting and relocation, volume expansion of fuel due to foaming and melt/debris … more
Date: June 15, 1990
Creator: Paik, I. K. (Westinghouse Savannah River Co., Aiken, SC (USA)); Kim, S. H.; Leonard, M. T. & Amos, C. N. (Science Applications International Corp., Albuquerque, NM (USA))
Partner: UNT Libraries Government Documents Department
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