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Synthesis of Mesostructured Copper Sulfide by Cation Exchange and Liquid Crystal Templating

Description: The development of synthetic pathways to yield advanced functional materials is an important aspect of materials science. In particular, the ability to control and manipulate the chemical composition and structure of inorganic nanomaterials is highly desirable. Two synthetic approaches which show great promise for producing the next generation of functional inorganic nanomaterials are (1) templating of supramolecular assemblies and (2) ion exchange within nanostructured inorganic solids to mani… more
Date: August 1, 2005
Creator: Lubeck, C R; Doyle, F M; Gash, A E; Satcher, J H & Han, T Y
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Correlation between Strand Stability and Magnet Performance

Description: Magnet programs at BNL, LBNL and FNAL have observed instabilities in high J{sub c} Nb{sub 3}Sn strands and magnets made from these strands. This paper correlates the strand stability determined from a short sample-strand test to the observed magnet performance. It has been observed that strands that carry high currents at high fields (greater than 10T) cannot sustain these same currents at low fields (1-3T) when the sample current is fixed and the magnetic field is ramped. This suggests that th… more
Date: April 16, 2005
Creator: Dietderich, Daniel R.; Bartlett, Scott E.; Caspi, Shlomo; Ferracin, Paolo; G ourlay, Stephen A.; Higley, Hugh C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Dynamic Response of Copper Subjected to Quasi-Isentropic, Gas-Gun Driven Loading

Description: A transmission electron microscopy study of quasi-isentropic high-pressure loading (peak pressures between 18 GPa and 52 GPa) of polycrystalline and monocrystalline copper was carried out. Deformation mechanisms and defect substructures at different pressures were analyzed. Current evidence suggests a deformation substructure consisting of twinning at the higher pressures and heavily dislocated laths and dislocation cells at the intermediate and lower pressures, respectively. Evidence of stacki… more
Date: September 29, 2005
Creator: Jarmakani, H.; McNaney, J. M.; Schneider, M. S.; Orlikowski, D.; Nguyen, J. H.; Kad, B. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Melting of Copper and Nickel at high pressure: the role of d-electrons

Description: Melting curves of Cu and Ni were measured to 97 GPa (3800 K) and 60 GPa (2970 K), respectively, in the laser-heated diamond cell. The measured melting temperatures of Cu are in good agreement with recent theoretical calculations. The melting slope (dT/dP) of Cu, which has a filled d-electron band, is about 2.5 times steeper than for Ni, which with one less electron, has a partially unfilled d-electron band. The relatively low melting slope obtained for Ni, measured using identical experimental … more
Date: April 11, 2005
Creator: Japel, S; Boehler, R & Ross, M
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nuclear effects in high-p(T) production of direct photons and neutral mesons

Description: The authors present results on the production of direct photons, {pi}{sup 0}, {eta} mesons on nuclear targets at large transverse momenta (p{sub T}). The data are from 530 and 800 GeV/c proton beams and 515 GeV/c {pi}{sup -} beams incident upon copper and beryllium targets that span the kinematic range of 1.0 < p{sub T} {approx}< 10 GeV/c at central rapidities.
Date: June 1, 2005
Creator: Apanasevich, L.; Bacigalupi, J.; Baker, W.; Begel, M.; Blusk, S.; Bromberg, C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development of the superconducting 3.9-GHz accelerating cavity at Fermilab

Description: A superconducting third harmonic 3.9 GHz accelerating cavity was proposed to improve the beam quality in the TTF-like photoinjector [1]. Fermilab has developed, built and tested several prototypes, including two copper 9-cell cavities, one niobium 3-cell cavity, and one 9-cell cavity. The helium vessel and frequency tuner for the 9-cell cavity was built and tested as well. In cold tests, we achieved a peak surface magnetic field of {approx}100mT, well above the 70mT specification. The accelerat… more
Date: May 1, 2005
Creator: Arkan, T.; Bauer, P.; Bellantoni, L.; Boffo, C.; Borissov, E.; Carter, H. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Science & Technology Review March 2005

Description: This issue of Science and Technology Review has the following articles: (1) Enhanced National Security through International Research Collaborations--Commentary by Stephen G. Cochran; (2) Building Networks of Trust through Collaborative Science--Livermore scientists are leading collaborative science and technology projects with colleagues from Central and South Asia and the Middle East; (3) Tracing the Steps in Nuclear Material Trafficking--The Laboratory.s nuclear science expertise is helping … more
Date: January 25, 2005
Creator: Henson, V E
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Dependence Study of $\Xi^{*0}$ and $\bar{\Xi}^{*0}$ in 250 GeV/c $\pi^-$. $K^-$ -nucleon Interactions

Description: A direct measurement of the mass number (A) dependence of the production of the hyperon {Xi}*{sup 0} and its opposite {bar {Xi}}*{sup 0} in {pi}{sup -}, K{sup -} beam-nucleon interactions at 250 GeV/c is reported. The data derive from the experiment E769 at Fermilab. The results were obtained for different targets: Be, Al, Cu and W. It was observed the data are found to be well described by the parametrization {sigma}{sub A} = {sigma}{sub 0}A{sup {alpha}}, {alpha} being calculated for different… more
Date: April 1, 2005
Creator: Seixas de Rezende, Fabio Antonio & /Rio de Janeiro, CBPF
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Correlation Between Strand Stability and Magnet Performance

Description: Magnet programs at BNL, LBNL and FNAL have observed instabilities in high J{sub c} Nb{sub 3}Sn strands and magnets made from these strands. This paper correlates the strand stability determined from a short sample-strand test to the observed magnet performance. It has been observed that strands that carry high currents at high fields (greater than 10 T) cannot sustain these same currents at low fields (1-3 T) when the sample current is fixed and the magnetic field is ramped. This suggests that … more
Date: June 1, 2005
Creator: Dietderich, D. R.; Bartlett, S. E.; Caspi, S.; Ferracin, P.; Gourlay, S. A.; Higley, H. C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Hot Surface Ionic Line Emission and Cold K-Inner Shell Emission From Petawatt-Laser Irradiated Cu Foil Targets

Description: A hot, T{sub e} {approx} 2- to 3-keV surface plasma was observed in the interaction of a 0.7-ps petawatt laser beam with solid copper-foil targets at intensities >10{sup 20} W/cm{sup 2}. Copper K-shell spectra were measured in the range of 8 to 9 keV using a single-photon-counting x-ray CCD camera. In addition to K{sub {alpha}} and K{sub {beta}} inner-shell lines, the emission contained the Cu He{sub {alpha}} and Ly{sub {alpha}} lines, allowing the temperature to be inferred. These lines hav… more
Date: December 13, 2005
Creator: Theobald, W.; Akli, K.; Clarke, R.; Delettrez, J. A.; Freeman, R. R.; Glenzer, S. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Atomistic modeling of shock-induced void collapse in copper

Description: Nonequilibrium molecular dynamics (MD) simulations show that shock-induced void collapse in copper occurs by emission of shear loops. These loops carry away the vacancies which comprise the void. The growth of the loops continues even after they collide and form sessile junctions, creating a hardened region around the collapsing void. The scenario seen in our simulations differs from current models that assume that prismatic loop emission is responsible for void collapse. We propose a new dislo… more
Date: March 9, 2005
Creator: Davila, L P; Erhart, P; Bringa, E M; Meyers, M A; Lubarda, V A; Schneider, M S et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Design study of 15-Tesla RHQT Nb3Al block type dipole magnet

Description: The design study of the block type 15-Tesla RHQT Nb{sub 3}Al dipole magnet, and its merits over Nb{sub 3}Sn magnets are presented. The copper stabilized RHQT Nb{sub 3}Al strand is now becoming commercially available for the application to the accelerator magnets. A 1 mm diameter RHQT Nb{sub 3}Al strand with filament size about 50 {mu}, non-copper Jc about 1000 A/mm{sup 2} at 15 Tesla at 4.2K, copper ratio of 50%, can now be produced over several hundred meters. The stress and strain characteris… more
Date: September 1, 2005
Creator: Yamada, R.; Ambrosio, G.; Barzi, E.; Kashikin, V.; Kikuchi, A.; Novitski, I. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Void Coalescence Processes Quantified through Atomistic and Multiscale Simulation

Description: Simulation of ductile fracture at the atomic scale reveals many aspects of the fracture process including specific mechanisms associated with void nucleation and growth as a precursor to fracture and the plastic deformation of the material surrounding the voids and cracks. Recently we have studied void coalescence in ductile metals using large-scale atomistic and continuum simulations. Here we review that work and present some related investigations. The atomistic simulations involve three-dime… more
Date: December 31, 2005
Creator: Rudd, R E; Seppala, E T; Dupuy, L M & Belak, J
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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NCSX Toroidal Field Coil Design

Description: The National Compact Stellarator Experiment (NCSX) is an experimental device whose design and construction is underway at the Department of Energy's Princeton Plasma Physics Laboratory (PPPL). The primary coil systems for the NCSX device consist of the twisted plasma-shaping Modular Coils, the Poloidal Field Coils, and the Toroidal Field (TF) Coils. The TF Coils are D-shaped coils wound from hollow copper conductor, and vacuum impregnated with a glass-epoxy resin system. There are 18 identical,… more
Date: October 7, 2005
Creator: Kalish M, Rushinski J, Myatt L, Brooks A, Dahlgren F, Chrzanowski J, Reiersen W, Freudenberg K
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Non-free-electron momentum- and thickness-dependent evolution ofquantum well states in the Cu/Co/Cu(001) system

Description: We present systematic k{sub {parallel}}-dependent measurements of the Fermi surface and underlying band structure of quantum well states in Cu/Co/Cu(001). Compared to bands from normal emission, we find a complicated evolution of ''split'' QW states as a function of the thicknesses of both the copper overlayer and the cobalt barrier layer. Self-consistent calculations show that the penetration of the quantum well states into the cobalt barrier layer is significant and leads to the observed very… more
Date: May 21, 2005
Creator: Rotenberg, Eli; Wu, Y. Z.; An, Joonhee M.; Van Hove, Michel A.; Canning, Andrew; Wang, Lin-Wang et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A novel method to synthesize high purity, nanostructured copper

Description: Nanostructured high purity (99.999%) copper foils, 10 cm in diameter and 22-25 microns thick were produced using nanoscale multilayer technology. The foils were produced using five different layer thicknesses ranging from 1.25 to 43.6 nm (18,000 to 520 layers). This process delivers the ability to produce multiple large-scale samples during a single deposition run with very small residual stresses. Tensile and indentation tests demonstrate that the material produced is a high strength copper ({… more
Date: August 30, 2005
Creator: Hodge, A M; Wang, Y M & Barbee, T W
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Test Bed for Superconducting Materials

Description: Superconducting rf cavities are increasingly used in accelerators. Gradient is a parameter of particular importance for the ILC. Much progress in gradient has been made over the past decade, overcoming problems of multipacting, field emission, and breakdown triggered by surface impurities. However, the quenching limit of the surface magnetic field for niobium remains a hard limitation on cavity fields sustainable with this technology. Further exploration of materials and preparation may offer a… more
Date: June 22, 2005
Creator: Nantista, C.; Tantawi, S.; Weisend, J.; Siemann, R. & Dolgashev, V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Finding the charm in 800 GeV/c p-Cu and p-Be single muon spectra

Description: Fermilab Experiment 866 took single muon data from 800 GeV/c ({radical}s = 38.8 GeV) p-Cu and p-Be interactions in an attempt to extract the inclusive nuclear open charm/anti-charm (D/{bar D}) differential cross sections as a function of p{sub T}. The muons were decay products from semi-leptonic decays of open charm mesons as well as decays from lighter non-charmed mesons ({pi}'s and K's). Data were taken simultaneously from two interaction regions; one of two thin nuclear targets and a copper … more
Date: January 1, 2005
Creator: Klinksiek, Stephen A.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Manufacturing Development of the NCSX Modular Coil Windings

Description: The modular coils on the National Compact Stellarator Experiment (NCSX) present a number of significant engineering challenges due to their complex shapes, requirements for high dimensional accuracy and the high current density required in the modular coils due to space constraints. In order to address these challenges, an R&D program was established to develop the conductor, insulation scheme, manufacturing techniques, and procedures. A prototype winding named Twisted Racetrack Coil (TRC) was … more
Date: September 27, 2005
Creator: Chrzanowski JH, Fogarty PJ, Heitzenroeder PJ, Meighan T, Nelson B, Raftopoulos S, Williamson D
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Novel Binders and Methods for Agglomeration of Ore

Description: Many metal extraction operations, such as leaching of copper, leaching of precious metals, and reduction of metal oxides to metal in high-temperature furnaces, require agglomeration of ore to ensure that reactive liquids or gases are evenly distributed throughout the ore being processed. Agglomeration of ore into coarse, porous masses achieves this even distribution of fluids by preventing fine particles from migrating and clogging the spaces and channels between the larger ore particles. Binde… more
Date: September 30, 2005
Creator: Kawatra, S. K.; Eisele, T. C.; Gurtler, J. A. & Lewandowski, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hydrogen Reduction of Ferric Ions for Use in Copper Electrowinning

Description: The conventional copper electrowinning process uses the water hydrolysis reaction as the anodic source of electrons. However this reaction generates acid mist and requires large quantities of energy. In order to improve energy efficiency and avoid acid mist, an alternative anodic reaction of ferrous ion oxidation has been proposed. This reaction does not involve evolution of acid mist and can be carried out at a lower cell voltage than the conventional process. However, because ferrous ions are… more
Date: January 1, 2005
Creator: Noah, Karl S.; Bruhn, Debby F.; Wey, John E. & Cherry, Robert S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High-Pressure Tailored Compression: Controlled Thermodynamic Paths

Description: We have recently carried out novel and exploratory dynamic experiments where the sample follows a prescribed thermodynamic path. In typical dynamic compression experiments, the samples are thermodynamically limited to the principal Hugoniot or quasi-isentrope. With recent developments in the functionally graded material impactor, we can prescribe and shape the applied pressure profile with similarly-shaped, non-monotonic impedance profile in the impactor. Previously inaccessible thermodynamic s… more
Date: October 21, 2005
Creator: Nguyen, J. H.; Orlikowski, D.; Streitz, F. H.; Moriarty, J. A. & Holmes, N. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Alternative Anode Reaction for Copper Electrowinning

Description: This report describes a project funded by the Department of Energy, with additional funding from Bechtel National, to develop a copper electrowinning process with lower costs and lower emissions than the current process. This new process also includes more energy efficient production by using catalytic-surfaced anodes and a different electrochemical couple in the electrolyte, providing an alternative oxidation reaction that requires up to 50% less energy than is currently required to electrowin… more
Date: July 1, 2005
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Resistive Wall Wakefield in the LCLS Undulator

Description: The authors have shown that in the Linac Coherent Light Source (LCLS) undulator region, because of the high frequency content in the bunch shape, the energy variation induced by the resistive wall wake is much larger when the (proper) ac conductivity calculation is performed, than for the often-used dc calculation. Using a round copper beam pipe will result in a (relative) energy variation many times the Pierce parameter, implying that a large fraction of beam will not reach saturation. Our res… more
Date: June 2, 2005
Creator: Bane, Karl L.F. & Stupakov, Gennady
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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