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Sample records for ion-textured ofhc copper

  1. Secondary electron emission characteristics of molybdenum-masked, ion-textured OFHC copper

    NASA Technical Reports Server (NTRS)

    Curren, Arthur N.; Jensen, Kenneth A.; Roman, Robert F.

    1990-01-01

    A method for producing a uniform, highly textured surface on oxygen-free, high conductivity (OFHC) copper by ion bombardment using sputtered molybdenum as a texture-inducing masking film was developed and used to provide samples for study. The purpose was to develop a basically OFHC copper surface having very low secondary electron emission characteristics. Surfaces having low secondary electron emission are a requirement for the electrodes of very high efficiency multistage depressed collectors (MDC's). Such MDC's are used in microwave amplifier traveling wave tubes for space communications and other applications. OFHC copper is the material most commonly used for MDC electrodes because it has high thermal conductivity, it is easy to machine, and its fabrication and brazing procedures are well established. However, its untreated surface displays relatively very high levels of secondary electron emissions. Textured OFHC copper samples were tested for true secondary electron emission and relative reflected primary electron yield at primary electron beam energy levels from 200 to 2000 eV and at direct (0 deg) to oblique (60 deg) beam impingement angles. The test results for three of the samples, each of which was processed in a slightly different way, are compared with each other and with test results for a machined OFHC copper sample. Although the textured samples are not represented here as having been processed optimally, their measured secondary electron emission characteristics are significantly lower than those of the untreated OFHC copper sample over the range of conditions studied. Importantly, the relative reflected primary electron yield of one of the textured samples is conspicuously lower than that of the others. Clearly, with further development, the molybdenum-masked ion-textured OFHC copper surface will be a promising material for high-efficiency MDC electrodes.

  2. Observation of diamond turned OFHC copper using Scanning Tunneling Microscopy

    SciTech Connect

    Grigg, D.A.; Russell, P.E.; Dow, T.A.

    1988-12-01

    Diamond turned OFHC copper samples have been observed within the past few months using the Scanning Tunneling Microscope. Initial results have shown evidence of artifacts which may be used to better understand the diamond turning process. The STM`s high resolution capability and three dimensional data representation allows observation and study of surface features unobtainable with conventional profilometry systems. Also, the STM offers a better quantitative means by which to analyze surface structures than the SEM. This paper discusses findings on several diamond turned OFHC copper samples having different cutting conditions. Each sample has been cross referenced using STM and SEM.

  3. Secondary electron emission characteristics of ion-textured copper and high-purity isotropic graphite surfaces

    NASA Technical Reports Server (NTRS)

    Curren, A. N.; Jensen, K. A.

    1984-01-01

    Experimentally determined values of true secondary electron emission and relative values of reflected primary electron yield for untreated and ion textured oxygen free high conductivity copper and untreated and ion textured high purity isotropic graphite surfaces are presented for a range of primary electron beam energies and beam impingement angles. This investigation was conducted to provide information that would improve the efficiency of multistage depressed collectors (MDC's) for microwave amplifier traveling wave tubes in space communications and aircraft applications. For high efficiency, MDC electrode surfaces must have low secondary electron emission characteristics. Although copper is a commonly used material for MDC electrodes, it exhibits relatively high levels of secondary electron emission if its surface is not treated for emission control. Recent studies demonstrated that high purity isotropic graphite is a promising material for MDC electrodes, particularly with ion textured surfaces. The materials were tested at primary electron beam energies of 200 to 2000 eV and at direct (0 deg) to near grazing (85 deg) beam impingement angles. True secondary electron emission and relative reflected primary electron yield characteristics of the ion textured surfaces were compared with each other and with those of untreated surfaces of the same materials. Both the untreated and ion textured graphite surfaces and the ion treated copper surface exhibited sharply reduced secondary electron emission characteristics relative to those of untreated copper. The ion treated graphite surface yielded the lowest emission levels.

  4. Metallurgical effects on the constitutive and fragmentation behavior of OFHC copper rings

    SciTech Connect

    Gourdin, W.H.

    1987-07-07

    Preliminary results of recent constitutive and fragmentation studies on electromagnetically launched expanding ring specimens of fully annealed OFHC copper with grain sizes of 10, 30-50, 90-120, and 150-200 ..mu..m are reported. Grain size correlations with material behavior are developed and briefly discussed in reference to previous data, with particular attention to thermodynamic models of fragmentation.

  5. Thermal conductance measurements of pressed OFHC copper contacts at liquid helium temperatures

    NASA Technical Reports Server (NTRS)

    Salerno, L. J.; Kittel, P.; Spivak, A. L.

    1983-01-01

    The thermal conductance of oxygen-free high conductivity (OFHC) copper sample pairs with surface finishes ranging from 0.1 to 1.6-micrometers rms roughness was investigated over the range of 1.6 to 6.0-K under applied contact forces up to 670 N. The thermal conductance increases with increasing contact force; however, no correlation can be drawn with respect to surface finish.

  6. Validating Material Modelling of OFHC Copper Using Dynamic Tensile Extrusion (DTE) Test at Different Impact Velocity

    NASA Astrophysics Data System (ADS)

    Bonora, Nicola; Testa, Gabriel; Ruggiero, Andrew; Iannitti, Gianluca; Hörnqvist, Magnus; Mortazavi, Nooshin

    2015-06-01

    In the Dynamic Tensile Extrusion (DTE) test, the material is subjected to very large strain, high strain rate and elevated temperature. Numerical simulation, validated comparing with measurements obtained on soft-recovered extruded fragments, can be used to probe material response under such extreme conditions and to assess constitutive models. In this work, the results of a parametric investigation on the simulation of DTE test of annealed OFHC copper - at impact velocity ranging from 350 up to 420 m/s - using phenomenological and physically based models (Johnson-Cook, Zerilli-Armstrong and Rusinek-Klepaczko), are presented. Preliminary simulation of microstructure evolution was performed using crystal plasticity package CPFEM, providing, as input, the strain history obtained with FEM at selected locations along the extruded fragments. Results were compared with EBSD investigation.

  7. Validating material modelling for OFHC copper using dynamic tensile extrusion (DTE) test at different velocity impact

    NASA Astrophysics Data System (ADS)

    Bonora, N.; Testa, G.; Ruggiero, A.; Iannitti, G.; Colliander, M. Hörnquist; Mortazavi, N.

    2017-01-01

    In the Dynamic Tensile Extrusion (DTE) test, the material is subjected to very large strain, high strain rate and elevated temperature. Numerical simulation, validated comparing with measurements obtained on soft-recovered extruded fragments, can be used to probe material response under such extreme conditions and to assess constitutive models. In this work, the results of a parametric investigation on the simulation of DTE test of annealed OFHC copper - at impact velocity ranging from 350 up to 420 m/s - using the modified Rusinek-Klepaczko model, are presented. Simulation of microstructure evolution was performed using the visco-plastic self consistent model (VPSC), providing, as input, the velocity gradient history obtained with FEM at selected locations along the axis of the fragment trapped in the extrusion die. Finally, results are compared with EBSD analysis.

  8. Modelling and simulation of dynamic recrystallization (DRX) in OFHC copper at very high strain rates

    NASA Astrophysics Data System (ADS)

    Testa, G.; Bonora, N.; Ruggiero, A.; Iannitti, G.; Persechino, I.; Hörnqvist, M.; Mortazavi, N.

    2017-01-01

    At high strain rates, deformation processes are essentially adiabatic and if the plastic work is large enough dynamic recrystallization can occur. In this work, an examination on microstructure evolution of OFHC copper in Dynamic Tensile Extrusion (DTE) test, performed at 400 m/s, was carried out. EBSD investigations, along the center line of the fragment remaining in the extrusion die, showed a progressive elongation of the grains, and an accompanying development of a strong <001> + <111> dual fiber texture. Discontinuous dynamic recrystallization (DRX) occurred at larger strains, and it was showed that nucleation occurred during straining. A criterion for DRX to occur, based on the evolution of Zener-Hollomon parameter during the dynamic deformation process, is proposed. Finally, DTE test was simulated using the modified Rusinek-Klepaczko constitutive model incorporating a model for the prediction of DRX initiation.

  9. Deformation and failure of OFHC copper under high strain rate shear compression

    NASA Astrophysics Data System (ADS)

    Ruggiero, Andrew; Testa, Gabriel; Bonora, Nicola; Iannitti, Gianluca; Persechino, Italo; Colliander, Magnus Hörnqvist

    2017-01-01

    Hat-shaped specimen geometries were developed to generate high strain, high-strain-rates deformation under prescribed conditions. These geometries offer also the possibility to investigate the occurrence of ductile rupture under low or negative stress triaxiality, where most failure models fail. In this work, three tophat geometries were designed, by means of extensive numerical simulation, to obtain desired stress triaxiality values within the shear region that develops across the ligament. Material failure was simulated using the Continuum Damage Model (CDM) formulation with a unilateral condition for damage accumulation and validated by comparing with quasi-static and high strain rate compression tests results on OFHC copper. Preliminary results seem to indicate that ductile tearing initiates at the specimen corner location where positive stress triaxiality occurs because of local rotation and eventually propagates along the ligament.

  10. Modelling and Simulation of Dynamic Recrystallization (DRX) In OFHC Copper at Very High Strain Rates

    NASA Astrophysics Data System (ADS)

    Testa, Gabriel; Bonora, Nicola; Ruggiero, Andrew; Iannitti, Gianluca; Hörnqvist, Magnus; Mortazavi, Nooshin

    2015-06-01

    At high strain rates, the deformation process is essentially adiabatic and if the plastic work is large enough, dynamic recrystallization can occur. In this work, an examination on microstructure evolution in Dynamic Tensile Extrusion (DTE) test of OFHC copper, performed at 400 m/s, was carried out. EBSD investigations, along the center line of the fragment remaining in the extrusion die, showed a progressive elongation of the grains, and an accompanying development of a strong < 001 > + < 111 > dual fiber texture. Meta-dynamic discontinuous dynamic recrystallization (DRX) occurred at larger strains, and it was showed that nucleation occurred during straining. A criterion, based on the evolution of Zener-Hollomon parameter during the dynamic deformation process, was proposed. Finally, DTE test was simulated using the modified Rusinek-Klepaczko constitutive model incorporating restoring effects induced by recrystallization processes.

  11. Laser ablative fluxless soldering (LAFS): 60Sn-40Pb solder wettability tests on laser cleaned OFHC copper substrates

    SciTech Connect

    Peebles, H. C.; Keicher, D. M.; Hosking, F. M.; Hlava, P. F.; Creager, N. A.

    1991-01-01

    OFHC copper substrates, cleaned by laser ablation under argon and helium gas, were tested for solder wettability by 60Sn-40Pb using an area-of-spread method. The wettability of copper surfaces cleaned under both argon and helium gas was found to equal or exceed the wettability obtained on this surface in air using a standard RMA flux. The area of spread on copper substrates cleaned under helium was eight times larger than the area of spread of substrates cleaned under argon. The enhanced spreading observed on the substrates cleaned under helium gas was found to be due to surface roughness. 11 refs., 8 figs., 2 tabs.

  12. Deformation and annealing behavior of heavily drawn oxygen-free high-conductivity (OFHC) copper

    NASA Astrophysics Data System (ADS)

    Waryoba, Daudi Rigenda

    Conductor wires used in pulsed high-field magnets require metallic materials with a beneficial combination of high mechanical strength to resist the Lorentz forces and high electrical conductivity to limit temperature excursions due to Joule heating. To achieve the required strength, most conductors are fabricated from microcomposite materials using the work hardening effect after heavy cold deformation such as wire drawing. Since the microstructure and texture of these microcomposites are complex, a detailed systematic study of these materials requires a separate study of the individual phases. This work presents a comprehensive study of the microstructure and microtexture evolution during deformation, and subsequent annealing of heavily deformed OFHC copper wires. Analytical tools used for investigation include optical microscopy, scanning electron microscopy (SEM), orientation-imaging microscopy (OIM) in SEM, and transmission electron microscopy (TEM). Mechanical properties were evaluated by tensile and microhardness testing. Some of the key features of the as-drawn wire are elongated grain size and shear bands. The intensity of the shear bands increased with strain. The ultimate tensile strength (UTS) and the microhardness of the heavily cold-drawn copper wires increased with strain, reached a saturation point and dropped at higher deformation strain. Deformation did not significantly alter the electrical conductivity of the wires. Deformed and recovered microstructures were characterized by a strong<111>+weak<100> duplex fiber texture. Nucleation of recrystallized grains occurred at shear bands and resulted in randomization of texture. On the other hand, recrystallization produced a strong<100>+weak<111>, which later changed to a <111> fiber texture during abnormal grain growth. A detailed analysis showed that recrystallization was a growth-controlled mechanism, and proceeds from the outer surface to the core. Interestingly, secondary recrystallization was

  13. Isolation of kinetic and spatial properties of uni-axial dynamic tensile loading of OFHC copper

    NASA Astrophysics Data System (ADS)

    Dennis-Koller, D.; Escobedo-Diaz, J. P.; Cerreta, E. K.; Bronkhorst, C. A.; Hansen, B.; Lebensohn, R.; Mourad, H.; Patterson, B.; Tonks, D.

    2012-08-01

    Materials performance is recognized as being central to many emergent technologies. Future technologies will place increasing demands on materials performance with respect to extremes in stress, strain, temperature, and pressure. In this study, the dynamic ductile damage evolution of OFHC Cu is explored as a test bed to understand the role of spatial effects due to loading profile and defect density as well as the role of the kinetics of tensile pulse evolution. Well-characterized OFHC Cu samples of 30 μm, 60 μm, 100 μm, and 200 μm grain sizes were subjected to plate impact uniaxial strain loading in spall geometry to produce early stage (incipient damage. Using 2D metallographic techniques, soft recovered samples were studied to statistically link mesoscale processes to continuum level observations of free surface particle velocity measured with VISAR. Based on these findings, mechanisms for the void nucleation/growth and coalescence are proposed.

  14. Thermal conductance measurements of pressed OFHC copper contacts at liquid helium temperatures

    NASA Technical Reports Server (NTRS)

    Salerno, L. J.; Kittel, P.; Spivak, A. L.

    1985-01-01

    The thermal conductance of oxygen-free high conductivity (COFHC) copper sample pairs with surface finishes ranging from 0.1 to 1.6-micrometers rms roughness was investigated over the range of 1.6 to 6.0-K under applied contact forces up to 670 N. The thermal conductance increases with increasing contact force; however, no correlation can be drawn with respect to surface finish.

  15. Cyclic fatigue analysis of rocket thrust chambers. Volume 1: OFHC copper chamber low cycle fatigue

    NASA Technical Reports Server (NTRS)

    Miller, R. W.

    1974-01-01

    A three-dimensional finite element elasto-plastic strain analysis was performed for the throat section of a regeneratively cooled rocket combustion chamber. The analysis employed the RETSCP finite element computer program. The analysis included thermal and pressure loads, and the effects of temperature dependent material properties, to determine the strain range corresponding to the chamber operating cycle. The analysis was performed for chamber configuration and operating conditions corresponding to a hydrogen-oxygen combustion chamber which was fatigue tested to failure. The computed strain range at typical chamber operating conditions was used in conjunction with oxygen-free, high-conductivity (OHFC) copper isothermal fatigue test data to predict chamber low-cycle fatigue life.

  16. Elastic-plastic-creep analysis of brazed carbon-carbon/OFHC divertor tile concepts for TPX

    SciTech Connect

    Chin, E.; Reis, E.E.

    1995-12-31

    The 7.5 MW/m{sup 2} heat flux requirements for the TPX divertor necessitate the use of high conductivity carbon-carbon (C-C) tiles that are brazed to annealed copper (OFHC) coolant tubes. Significant residual stresses are developed in the C-C tiles during the braze process due to large differences in the thermal expansion coefficients between these materials. Analyses which account for only the elastic-plastic strains developed in the OFHC tube may not accurately characterize the behavior of the tube during brazing. The elevated temperature creep behavior of the copper coolant tubes intuitively should reduce the calculated residual stresses in the C-C tiles. Two divertor tile concepts, the monoblock and the archblock, were analyzed for residual stress using 2-D finite element analysis for elastic-plastic-creep behavior of the OFHC tube during an assumed braze cooldown cycle. The results show that the inclusion of elevated temperature creep effects decrease the calculated residual stresses by only about 10% when compared to those analyses in which only elastic-plastic behavior of the OFHC is accounted for. The primary reason that creep effects at higher temperatures are not more significant is due to the low yield stress and nearly flat-top stress-strain curve of annealed OFHC. Since high temperature creep plays less of a role in the residual stress levels than previously thought, future scoping studies can be done in an elastic-plastic analysis with confidence that the stresses will be within approximately 10% of an elastic-plastic-creep analysis.

  17. Mechanical and chemical effects of ion-texturing biomedical polymers

    NASA Technical Reports Server (NTRS)

    Weigand, A. J.; Cenkus, M. A.

    1979-01-01

    To determine whether sputter etching may provide substantial polymer surface texturing with insignificant changes in chemical and mechanical properties, an 8 cm beam diameter, electron bombardment, argon ion source was used to sputter etch (ion-texture process) nine biomedical polymers. The materials included silicone rubber, 32% carbon impregnated polyolefin, polyoxymethylene, polytetrafluoroethylene, ultrahigh molecular weight (UHMW) polyethylene, UHMW polyethylene with carbon fibers (10%), and several polyurethanes (bioelectric, segmented, and cross linked). Ion textured microtensile specimens of each material except UHMW polyethylene and UHMW polyethylene with 10% carbon fibers were used to determine the effect of ion texturing on tensile properties. Scanning electron microscopy was used to determine surface morphology changes, and electron spectroscopy for chemical analysis was used to analyze the near surface chemical changes that result from ion texturing. Ion energies of 500 eV with beam current densities ranging from 0.08 to 0.19 mA/sq cm were used to ion texture the various materials. Standard microtensile specimens of seven polymers were exposed to a saline environment for 24 hours prior to and during the tensile testing. The surface chemical changes resulting from sputter etching are minimal in spite of the often significant changes in the surface morphology.

  18. Secondary electron emission characteristics of untreated and ion-textured titanium

    NASA Technical Reports Server (NTRS)

    Curren, Arthur N.; Jensen, Kenneth A.; Blackford, Gary A.

    1989-01-01

    Experimentally determined values of true secondary electron emission and relative values of reflected primary electron yield are presented for untreated (simply machined) and ion-textured, high-purity titanium over ranges of primary electron beam energies and beam impingement angles. The purpose of the investigation was to explore the feasibility of using titanium as electrode material in the multistage depressed collectors (MDC's) used in microwave amplifier traveling wave tubes (TWT's) for space communications and aircraft applications. Because of its relatively low density and thermal expansion characteristics and relatively high strength, thermal emissivity, and melting temperature, titanium presents itself as a possible candidate for the MDC electrode application. A detailed description of the method of ion texturing the titanium is included. Although the ion-treated surface considered in this study is not presented as being optimum from the standpoint of secondary electron emission suppression, it nevertheless serves to demonstrate that the surface can be modified by this procedure to significantly reduce these emission characteristics relative to those of the untreated surface. Further studies can reasonably be expected to produce surfaces with even lower secondary emission characteristics. The titanium surface were tested at primary electron beam energies of 200 to 2000 eV and at direct (0 deg) to near-grazing (85 deg) beam impingement angles. True secondary electron emission and relative reflected primary electron yield characteristics of the surfaces were compared with each other and with textured titanium surface exhibited secondary electron emission characteristics sharply lower than those exhibited by untreated titanium or copper. Clearly, then, in consideration of the secondary electron emission suppression of ion-textured titanium along with its other favorable physical properties, it must be included as a potential candidate for use as MDC electrode

  19. The characterization of copper alloys for the application of fusion reactors

    SciTech Connect

    Ishiyama, S.; Fukaya, K.; Eto, M.; Akiba, M.

    1995-12-31

    Three kinds of candidate copper alloys for divertor structural materials of fusion experimental reactors, that is, Oxygen Free High thermal conductivity Copper (OFHC), alumina disperse reinforced copper (DSC) and the composite of W and Cu (W/Cu), were prepared for strength and fatigue tests at temperatures ranging from R.T. to 500 C in a vacuum. High temperature strength of DSC and W/Cu with rapid fracture after peak loading at the temperatures is higher than that of OFHC by factor of 2, but fracture strains of DFC and W/Cu are smaller than that of OFHC. Fatigue life of DSC, which shows the same fatigue behavior of OFHC at room temperature, is longer than other materials at 400 C. Remarkable fatigue life reduction of OFHC found in this experiment is to be due to recrystallization of OFHC yielded above 400 C.

  20. High temperature, low-cycle fatigue of copper-base alloys in argon. Part 1: Preliminary results for 12 alloys at 1000 F (538 C)

    NASA Technical Reports Server (NTRS)

    Conway, J. B.; Stentz, R. H.; Berling, J. T.

    1973-01-01

    Short-term tensile evaluations at room temperature and 538 C and low-cycle fatigue evaluations at 538 C are presented for the following materials: Zirconium copper-annealed, Zirconium copper-1/4 hard, Zirconium copper-1/2 hard, Tellurium copper-1/2 hard, Chromium copper-SA and aged, OFHC copper-hard, OFHC copper-1/4 hard, OFHC copper-annealed, Silver-as drawn, Zr-Cr-Mg copper-SA, CW and aged, Electroformed copper-30-35 ksi, and Co-Be-Zr- copper-SA, aged. A total of 50 tensile tests and 76 low-cycle fatigue tests were performed using a strain rate of 0.2 percent per second.

  1. Behavior of CuP and OFHC Cu anodes under electrodeposition conditions

    SciTech Connect

    Frankel, G.S.; Schrott, A.G.; Horkans, J.; Andricacos, P.C. . Thomas J. Watson Research Center); Isaacs, H.S. )

    1992-01-01

    Films formed on CuP (with 0.05 wt % P) and OFHC Cu anodes in electroplating solutions were studied by X-ray Photoelectron Spectroscopy, X-ray Absorption Spectroscopy, electrochemical methods, and a newly developed gravimetric technique. The black film formed on CuP in Cl-containing solutions was found to resemble a porous sponge composed of CuCl but laden/with concentrated CuSO{sub 4} solution. The difference between the buoyancy-corrected measured mass change and the charge-equivalent mass change was found to have two components: a reversible part that comes and goes as the current is turned on and off, and an irreversible part that remains on the surface and increase in mass with time. The irreversible part results from the anodic film, which increases linearly with charge density but independent of current density. The reversible part of the mass change arises from the weight of the diffusion layer. In contrast to CuP, OFHC Cu releases much more Cu{sup +1} during anodic polarization and forms a poorly-adherent anodic film that is considerably heavier than the black film for a given charge density.

  2. Behavior of CuP and OFHC Cu anodes under electrodeposition conditions

    SciTech Connect

    Frankel, G.S.; Schrott, A.G.; Horkans, J.; Andricacos, P.C.; Isaacs, H.S.

    1992-08-01

    Films formed on CuP (with 0.05 wt % P) and OFHC Cu anodes in electroplating solutions were studied by X-ray Photoelectron Spectroscopy, X-ray Absorption Spectroscopy, electrochemical methods, and a newly developed gravimetric technique. The black film formed on CuP in Cl-containing solutions was found to resemble a porous sponge composed of CuCl but laden/with concentrated CuSO{sub 4} solution. The difference between the buoyancy-corrected measured mass change and the charge-equivalent mass change was found to have two components: a reversible part that comes and goes as the current is turned on and off, and an irreversible part that remains on the surface and increase in mass with time. The irreversible part results from the anodic film, which increases linearly with charge density but independent of current density. The reversible part of the mass change arises from the weight of the diffusion layer. In contrast to CuP, OFHC Cu releases much more Cu{sup +1} during anodic polarization and forms a poorly-adherent anodic film that is considerably heavier than the black film for a given charge density.

  3. An Effective Secondary Electron Emission Suppression Treatment For Copper MDC

    NASA Technical Reports Server (NTRS)

    Curren, Arthur N.; Long, Kenwyn J.; Jensen, Kenneth A.; Roman, Robert F.

    1993-01-01

    Untreated oxygen-free, high-conductivity (OFHC) copper, commonly used for MDC electrodes, exhibits relatively high secondary electron emission characteristics. This paper describes a specialized ion-bombardment procedure for texturing copper surfaces which sharply reduces the emission properties relative to untreated copper. The resulting surface is a particle-free, robust, uniformly highly-textured all-metal structure. The use of this process requires no modifications to copper machining, brazing, or other MDC normal fabrication procedures. The flight TWT for a planned NASA deep space probe, the Cassini Mission, will incorporate copper MDC electrodes treated with the method described here.

  4. Copper

    Integrated Risk Information System (IRIS)

    Copper ; CASRN 7440 - 50 - 8 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effects )

  5. Grain size effects on the high strain rate deformation of copper

    NASA Astrophysics Data System (ADS)

    Stevenson, Michael Earle

    The high strain rate (>104/s) mechanical properties of OFHC copper were studied by the Taylor impact test for a series of copper grain sizes from 31 to 152 mum. The results are analyzed by both analytical and finite element. There is a significant increase in the dynamic strength of OFHC copper for strain rates greater than approximately 104/s. This strength increase is also dependent upon the grain size of the OFHC copper prior to testing and follows a classical Hall-Petch relationship. In addition to the analytical and finite element models, a universal dynamic stress-strain curve was developed and constructed for each grain size of the OFHC copper. The characterization parameters determined from the universal dynamic stress-strain curve are also grain size dependent. Many of these parameters also follow the classical Hall-Petch trend. Post-impact microstructures of the copper can be generalized into five distinct regions. Beginning at the specimen impact face, those regions are: (i) a nanocrystalline, or sub-micron grain size layer; (ii) a dynamically recrystallized region; (iii) a region of high density (111)[112¯] twinning; (iv) a section dominated by dislocation plastic flow, or slip and (v) the specimen portion where the deformation is completely elastic. The five regions can be related to the mechanical properties derived from the individual models and the universal dynamic stress-strain curve with consideration of the initial microstructure of the copper. The results of this dissertation suggest that there is a direct linkage between the dynamic mechanical state of stress during the impact tests and both the initial and final metallurgical microstructures of the copper.

  6. Experimental Evaluation of the Taylor-Type Polycrystal Model for the Finite Deformation of an FCC Metal (OFHC Copper)

    DTIC Science & Technology

    1991-05-01

    McClintock , Massachusetts Institute of Technology, Department of Mechanical Engineering, Cambridge, MA 02139 1 R. M. McMeeking, University of California...at Santa Barbara , Department of Material Science, Santa Barbara , CA 93111 1 Prof. Alan Miller, Stanford Univerrsity, Department of Materials Science

  7. Experimental Investigation on Thermoresistance between AlN, Bi-2223 and OFHC in High Tc- Direct Cooling Technology

    NASA Astrophysics Data System (ADS)

    Wang, H. L.; Rao, R. S.; Wang, J.

    2014-12-01

    In the development of high temperature superconducting (HTS) direct cooling technology, the high electric insulation high heat conducting AlN has become one of the important components. The thermal contact resistance between AlN, Bi-2223 and OFHC is investigated by experiment with a G-M cryocooler as the source of cooling. The heat conductivity of AlN is measured between 29 and 160 K temperatures. When the temperature on the interface layer side of Bi-2223 is 55 K, under the action of the contact pressure of 0.5469 MPa, the thermal contact resistance between AlN and Bi-2223 is 38.86 times to the thermal conduction resistance of a 10 mm thick AlN pad. Baced on micro-nanocryogenics, it is proposed that the thermal contact resistance is one of the crucial techniques to be attacked in HTS direct cooling technology.

  8. Reverse Taylor Tests on Ultrafine Grained Copper

    SciTech Connect

    Mishra, A.; Meyers, M. A.; Martin, M.; Thadhani, N. N.; Gregori, F.; Asaro, R. J.

    2006-07-28

    Reverse Taylor impact tests have been carried out on ultrafine grained copper processed by Equal Channel Angular Pressing (ECAP). Tests were conducted on an as-received OFHC Cu rod and specimens that had undergone sequential ECAP passes (2 and 8). The average grain size ranged from 30 {mu}m for the initial sample to less than 0.5 {mu}m for the 8-pass samples. The dynamic deformation states of the samples, captured by high speed digital photography were compared with computer simulations run in AUTODYN-2D using the Johnson-Cook constitutive equation with constants obtained from stress-strain data and by fitting to an experimentally measured free surface velocity trace. The constitutive response of copper of varying grain sizes was obtained through quasistatic and dynamic mechanical tests and incorporation into constitutive models.

  9. Attenuation of shock waves in copper and stainless steel

    SciTech Connect

    Harvey, W.B.

    1986-06-01

    By using shock pins, data were gathered on the trajectories of shock waves in stainless steel (SS-304L) and oxygen-free-high-conductivity copper (OFHC-Cu). Shock pressures were generated in these materials by impacting the appropriate target with thin (approx.1.5 mm) flying plates. The flying plates in these experiments were accelerated to high velocities (approx.4 km/s) by high explosives. Six experiments were conducted, three using SS-304L as the target material and three experiments using OFHC-Cu as the target material. Peak shock pressures generated in the steel experiments were approximately 109, 130, and 147 GPa and in the copper experiments, the peak shock pressures were approximately 111, 132, and 143 GPa. In each experiment, an attenuation of the shock wave by a following release wave was clearly observed. An extensive effort using two characteristic codes (described in this work) to theoretically calculate the attenuation of the shock waves was made. The efficacy of several different constitutive equations to successfully model the experiments was studied by comparing the calculated shock trajectories to the experimental data. Based on such comparisons, the conclusion can be drawn that OFHC-Cu enters a melt phase at about 130 GPa on the principal Hugoniot. There was no sign of phase changes in the stainless-steel experiments. In order to match the observed attenuation of the shock waves in the SS-304L experiments, it was necessary to include strength effects in the calculations. It was found that the values for the parameters in the strength equations were dependent on the equation of state used in the modeling of the experiments. 66 refs., 194 figs., 77 tabs.

  10. Low-cycle-fatigue behavior of copper materials and their use in synchrotron beamline components

    SciTech Connect

    Wang, Z.; Nian, T.; Ryding, D.; Kuzay, T.M.

    1993-09-01

    The third generation synchrotron facilities such as the 7-GeV Advanced Photon Source Project (APS) generate x-ray beams with very high heat loads and heat flux levels. The front-end and beamline components are required to sustain total heat loads of 5 to 15 kW and heat flux levels exceeding 400 W/mm{sup 2}. Grazing geometry and enhanced heat transfer techniques are used in the design of such components to reduce heat flux levels below the 30 W/mm{sup 2} level, which is sustainable by the special copper materials routinely used in the component design. Although the resulting maximum surface temperatures can be sustained, the structural stresses and the fatigue issues remain viable concerns for the copper, particularly under brazing or bonding of the parts. Brazing and bonding are almost always utilized in the design of the components, and the drastically lowered yield stress of the annealed copper subjected to bonding temperatures above 400{degree}C is a real concern. Such materials with reduced post-bonding stress levels easily reach yield point under thermal stresses during ordinary use on the beamline. The resulting plastic deformation in each load cycle may cause low-cycle-fatigue problems. The two common copper materials are OFHC and Glidcop. This paper critically reviews the available literature for low-cycle-fatigue properties, of OFHC at the elevated temperatures typically found in synchrotron operations.

  11. Low-cycle fatigue analysis of a cooled copper combustion chamber

    NASA Technical Reports Server (NTRS)

    Miller, R. W.

    1974-01-01

    A three-dimensional finite element elastoplastic strain analysis was performed for the throat section of regeneratively cooled rocket engine combustion chamber. The analysis included thermal and pressure loads, and the effects of temperature dependent material properties, to determine the strain range corresponding to the engine operating cycle. The strain range was used in conjunction with OFHC copper isothermal fatigue test data to predict engine low-cycle fatigue life. The analysis was performed for chamber configuration and operating conditions corresponding to a hydrogen-oxygen chamber which was fatigue tested to failure at the NASA Lewis Research Center.

  12. Fatigue behavior of copper and selected copper alloys for high heat flux applications

    SciTech Connect

    Leedy, K.D.; Stubbins, J.F.; Singh, B.N.; Garner, F.A.

    1996-04-01

    The room temperature fatigue behavior of standard and subsize specimens was examined for five copper alloys: OFHC Cu, two CuNiBe alloys, a CuCrZr alloy, and a Cu-Al{sub 2}O{sub 3} alloy. Fatigue tests were run in strain control to failure. In addition to establishing failure lives, the stress amplitudes were monitored as a function of numbers of accrued cycles. The results indicate that the alloys with high initial yield strengths provide the best fatigue response over the range of failure lives examined in the present study: N{sub f} = 10{sup 3} to 10{sup 6}. In fact, the fatigue performance of the best alloys is dominated by the elastic portion of the strain range, as would be expected from the correlation of performance with yield properties. The alumina strengthened alloy and the two CuNiBe alloys show the best overall performance of the group examined here.

  13. Qualification of electron-beam welded joints between copper and stainless steel for cryogenic application

    NASA Astrophysics Data System (ADS)

    Lusch, C.; Borsch, M.; Heidt, C.; Magginetti, N.; Sas, J.; Weiss, K.-P.; Grohmann, S.

    2015-12-01

    Joints between copper and stainless steel are commonly applied in cryogenic systems. A relatively new and increasingly important method to combine these materials is electron-beam (EB) welding. Typically, welds in cryogenic applications need to withstand a temperature range from 300K down to 4K, and pressures of several MPa. However, few data are available for classifying EB welds between OFHC copper and 316L stainless steel. A broad test program was conducted in order to qualify this kind of weld. The experiments started with the measurement of the hardness in the weld area. To verify the leak-tightness of the joints, integral helium leak tests at operating pressures of 16 MPa were carried out at room- and at liquid nitrogen temperature. The tests were followed by destructive tensile tests at room temperature, at liquid nitrogen and at liquid helium temperatures, yielding information on the yield strength and the ultimate tensile strength of the welds at these temperatures. Moreover, nondestructive tensile tests up to the yield strength, i.e. the range in which the weld can be stressed during operation, were performed. Also, the behavior of the weld upon temperature fluctuations between room- and liquid nitrogen temperature was tested. The results of the qualification indicate that EB welded joints between OFHC copper and 316L stainless steel are reliable and present an interesting alternative to other technologies such as vacuum brazing or friction welding.

  14. Effects on LDEF exposed copper film and bulk

    NASA Technical Reports Server (NTRS)

    Peters, Palmer N.; Gregory, John C.; Christl, Ligia C.; Raikar, Ganesh N.

    1991-01-01

    Two forms of copper were exposed to the Long Duration Exposure Facility (LDEF) Mission 1 environment: a copper film, initially 74.2 plus or minus 1.1 nm thick sputter coated on a fused silica flat and a bulk piece of oxygen-free, high conductivity (OFHC) copper. The optical density of the copper film changed from 1.33 to 0.70 where exposed, and the film thickness increased to 106.7 plus or minus 0.5 nm where exposed. The exposed area appears purple by reflection and green by transmission for the thin film and maroon color for the bulk copper piece. The exposed areas increased in thickness, but only increase in the thickness of the thin film sample could be readily measured. The increase in film thickness is consistent with the density changes occurring during conversion of copper to an oxide. However, we have not been able to confirm appreciable conversion to an oxide by x-ray diffraction studies. We have not yet subjected the sample to e-beams or more abusive investigations out of concern that the film might be modified.

  15. Effects on LDEF exposed copper film and bulk

    NASA Technical Reports Server (NTRS)

    Peters, Palmer N.; Gregory, John C.; Christl, Ligia C.; Raikar, Ganesh N.

    1992-01-01

    Two forms of copper were exposed to the Long Duration Exposure Facility (LDEF) Mission 1 environment: a copper film initially 74.2 plus or minus 1.1 nm thick sputter coated on a fused silical flat and a bulk piece of oxygen free, high conductivity (OFHC) copper. The optical density of the copper film changed from 1.33 to 0.70 where exposed and the film thickness increased to 106.7 plus or minus 0.5 nm where exposed. The exposed area appears purple by reflection and green by transmission for the thin film and maroon color for the bulk copper piece. The exposed areas increased in thickness, but only increase in the thickness of thin film samples could be readily measured. The increase in film thickness is consistent with the density changes occurring during conversion of copper to an oxide. However, we have not been able to confirm appreciable conversion to an oxide by x ray diffraction studies. We have not yet subjected the sample to e-beams or more abusive conditions out of concern that the film might be modified.

  16. The interaction of atomic oxygen with copper: An XPS, AES, XRD, optical transmission, and stylus profilometry study

    NASA Technical Reports Server (NTRS)

    Raikar, Ganesh N.; Gregory, John C.; Christl, Ligia C.; Peters, Palmer N.

    1993-01-01

    The University of Alabama in Huntsville (UAH) experiment A-0114 was designed to study the reaction of material surfaces with low earth orbits (LEO) atmospheric oxygen. The experiment contained 128 one-inch circular samples; metals, polymers, carbons, and semiconductors. Half of these samples were exposed on the front of the Long Duration Exposure Facility (LDEF) and remaining on the rear. Among metal samples, copper has shown some interesting new results. There were two forms of copper samples: a thin film sputter-coated on fused silica and a solid piece of OFHC copper. They were characterized by x-ray and Auger electron spectroscopies, x-ray diffraction, and high resolution profilometry. Cu 2p core level spectra were used to demonstrate the presence of Cu2O and CuO and to determine the oxidation states.

  17. Steady Deflagration of PBX-9501 Within a Copper Cylinder

    SciTech Connect

    Pemberton, Steven J.; Herrera, Dennis H.; Herrera, Tommy J.; Arellano, Jesus C.; Sandoval, Thomas D.

    2012-06-26

    A copper cylinder cook-off experiment has been designed to cause steady deflagration in PBX-9501 explosive material. The design is documented and preliminary copper expansion results are presented for steady deflagration with a reaction speed of 1092 +/- 24 m/s. The expansion of reaction products from the detonation of an explosive is something that is well understood, and reasonably simulated using documented equations of state (EOS) for many explosives of interest. These EOS were historically measured using a 'standard' copper cylinder test design; this design comprised an annealed, oxygen-free high conductivity (OFHC) copper tube filled with explosive material and detonated from one end. Expansion of the copper wall was measured as a function of time using either a streak camera (for classic testing), or more recently using laser velocimetry techniques. Expansion data were then used to derive the EOS in various preferred forms - which are not discussed here for the sake of brevity. [Catanach, et. al., 1999] When an explosive deflagrates rather than detonating, simulation becomes more difficult. Reaction products are released on a slower time scale, and the reactions are much more affected by the geometry and local temperature within the reaction environment. It is assumed that the standard, documented EOS will no longer apply. In an effort to establish a first order approximation of deflagration product behavior, a cook-off test has been designed to cause steady deflagration in PBX-9501 explosive material, and to record the copper expansion profile as a function of time during this test. The purpose of the current paper is to document the initial test design and report some preliminary results. A proposal for modification of the design is also presented.

  18. Optical properties of ion beam textured metals. [using copper, silicon, aluminum, titanium and stainless steels

    NASA Technical Reports Server (NTRS)

    Hudson, W. R.; Weigand, A. J.; Mirtich, M. J.

    1977-01-01

    Copper, silicon, aluminum, titanium and 316 stainless steel were textured by 1000 eV xenon ions from an 8 cm diameter electron bombardment ion source. Simultaneously sputter-deposited tantalum was used to facilitate the development of the surface microstructure. Scanning electron microscopy of the ion textured surfaces revealed two types of microstructure. Copper, silicon, and aluminum developed a cone structure with an average peak-to-peak distance ranging from 1 micron for silicon to 6 microns for aluminum. Titanium and 316 stainless steel developed a serpentine ridge structure. The average peak-to-peak distance for both of these materials was 0.5 micron. Spectral reflectance was measured using an integrating sphere and a holraum reflectometer. Total reflectance for air mass 0 and 2, solar absorptance and total emittance normalized for a 425 K black body were calculated from the reflectance measurements.

  19. Mechanical behavior and strength in spalled copper

    NASA Astrophysics Data System (ADS)

    Vachhani, Shraddha J.; Trujillo, Carl P.; Potocki, Mark L.; Martinez, Daniel T.; Lovato, Manuel L.; Gray, George T.; Cerreta, Ellen K.

    2017-01-01

    The bulk compressive and tensile response of samples machined from the different regions of dynamically damaged OFHC copper is examined in combination with post-mortem analysis of the recovered sample. This was done using optical microscopy and electron back-scatter diffraction to understand the strength and mechanical behavior of a material deformed under dynamic loading conditions. Stored plastic work in the shocked samples produced significant hardening in all the samples. It was also observed that the samples containing a dynamically induced damage field were slightly harder and showed enhanced yield strength over material simply subjected to shock and release that showed no dynamic damage. This was attributed to the excess work hardening around voids induced during incipient spall. By comparing the responses of two specimens with differing amounts of dynamic damage, it was concluded that there appears to be a limit to the amount of dynamic damage, after which the enhanced yield strength in the material with dynamic damage will cease to exist.

  20. Copper hypersensitivity.

    PubMed

    Fage, Simon W; Faurschou, Annesofie; Thyssen, Jacob P

    2014-10-01

    The world production of copper is steadily increasing. Although humans are widely exposed to copper-containing items on the skin and mucosa, allergic reactions to copper are only infrequently reported. To review the chemistry, biology and accessible data to clarify the implications of copper hypersensitivity, a database search of PubMed was performed with the following terms: copper, dermatitis, allergic contact dermatitis, contact hypersensitivity, contact sensitization, contact allergy, patch test, dental, IUD, epidemiology, clinical, and experimental. Human exposure to copper is relatively common. As a metal, it possesses many of the same qualities as nickel, which is a known strong sensitizer. Cumulative data on subjects with presumed related symptoms and/or suspected exposure showed that a weighted average of 3.8% had a positive patch test reaction to copper. We conclude that copper is a very weak sensitizer as compared with other metal compounds. However, in a few and selected cases, copper can result in clinically relevant allergic reactions.

  1. Copper transport.

    PubMed

    Linder, M C; Wooten, L; Cerveza, P; Cotton, S; Shulze, R; Lomeli, N

    1998-05-01

    In adult humans, the net absorption of dietary copper is approximately 1 mg/d. Dietary copper joins some 4-5 mg of endogenous copper flowing into the gastrointestinal tract through various digestive juices. Most of this copper returns to the circulation and to the tissues (including liver) that formed them. Much lower amounts of copper flow into and out of other major parts of the body (including heart, skeletal muscle, and brain). Newly absorbed copper is transported to body tissues in two phases, borne primarily by plasma protein carriers (albumin, transcuprein, and ceruloplasmin). In the first phase, copper goes from the intestine to the liver and kidney; in the second phase, copper usually goes from the liver (and perhaps also the kidney) to other organs. Ceruloplasmin plays a role in this second phase. Alternatively, liver copper can also exit via the bile, and in a form that is less easily reabsorbed. Copper is also present in and transported by other body fluids, including those bathing the brain and central nervous system and surrounding the fetus in the amniotic sac. Ceruloplasmin is present in these fluids and may also be involved in copper transport there. The concentrations of copper and ceruloplasmin in milk vary with lactational stage. Parallel changes occur in ceruloplasmin messenger RNA expression in the mammary gland (as determined in pigs). Copper in milk ceruloplasmin appears to be particularly available for absorption, at least in rats.

  2. Graphite fiber textile preform/copper matrix composites

    SciTech Connect

    Gilatovs, G.J.; Lee, B.; Bass, L.

    1995-08-01

    Graphite fiber reinforced/copper matrix composites have sufficiently high thermal conduction to make them candidate materials for critical heat transmitting and rejection components. The term textile composites arises because the preform is braided from fiber tows, conferring three-dimensional reinforcement and near net shape. The principal issues investigated in the past two years have centered on developing methods to characterize the preform and fabricated composite and on braidability. It is necessary to have an analytic structural description for both processing and final property modeling. The structure of the true 3-D braids used is complex and has required considerable effort to model. A structural mapping has been developed as a foundation for analytic models for thermal conduction and mechanical properties. The conductivity has contributions both from the copper and the reinforcement. The latter is accomplished by graphitization of the fibers, the higher the amount of graphitization the greater the conduction. This is accompanied by an increase in the fiber modulus, which is desirable from a stiffness point of view but decreases the braidability; the highest conductivity fibers are simply too brittle to be braided. While a number of preforms have been fabricated, one other complication intervenes; graphite and copper are immiscible, resulting in a poor mechanical bond and difficulties in infiltration by molten copper. The approach taken is to utilize a proprietary fiber coating process developed by TRA, of Salt Lake City, Utah, which forms an itermediary bond. A number of preforms have been fabricated from a variety of fiber types and two sets of these have been infiltrated with OFHC copper, one with the TRA coating and one without. Mechanical tests have been performed using a small-scale specimen method and show the coated specimens to have superior mechanical properties.

  3. Graphite fiber textile preform/copper matrix composites

    NASA Technical Reports Server (NTRS)

    Gilatovs, G. J.; Lee, Bruce; Bass, Lowell

    1995-01-01

    Graphite fiber reinforced/copper matrix composites have sufficiently high thermal conduction to make them candidate materials for critical heat transmitting and rejection components. The term textile composites arises because the preform is braided from fiber tows, conferring three-dimensional reinforcement and near net shape. The principal issues investigated in the past two years have centered on developing methods to characterize the preform and fabricated composite and on braidability. It is necessary to have an analytic structural description for both processing and final property modeling. The structure of the true 3-D braids used is complex and has required considerable effort to model. A structural mapping has been developed as a foundation for analytic models for thermal conduction and mechanical properties. The conductivity has contributions both from the copper and the reinforcement. The latter is accomplished by graphitization of the fibers, the higher the amount of graphitization the greater the conduction. This is accompanied by an increase in the fiber modulus, which is desirable from a stiffness point of view but decreases the braidability; the highest conductivity fibers are simply too brittle to be braided. Considerable effort has been expended on determining the optimal braidability--conductivity region. While a number of preforms have been fabricated, one other complication intervenes; graphite and copper are immiscible, resulting in a poor mechanical bond and difficulties in infiltration by molten copper. The approach taken is to utilize a proprietary fiber coating process developed by TRA, of Salt Lake City, Utah, which forms an itermediary bond. A number of preforms have been fabricated from a variety of fiber types and two sets of these have been infiltrated with OFHC copper, one with the TRA coating and one without. Mechanical tests have been performed using a small-scale specimen method and show the coated specimens to have superior

  4. HIGH-STRAIN RATE RESPONSE OF ULTRA-FINE GRAINED COPPER: EXPERIMENTS AND ANALYSIS

    SciTech Connect

    Mishra, Anuj; Kad, Bimal; Martin, Morgana; Thadhani, Naresh; Kenik, Edward A; Myers, Marc A.

    2008-07-01

    The high-strain rate response of ultra-fine grained (UFG) copper processed by Equal Channel Angular Pressing (ECAP) was characterized by reverse Taylor impact and Hopkinson-bar experiments. Two types of copper samples are tested using Hopkinson bar: (a) cylindrical samples to investigate the response at high strain-rates,(b) hat shaped samples to compare the shear band characteristics in UFG copper with the ones that have been studied in coarse grained samples. This can be attributed to the high strain-rate sensitivity of the fine grained FCC metals. Upon impact, the samples were found to undergo heat induced static recrystallization at a calculated temperature of 360K, indicating that the UFG copper is thermally unstable. Reverse Taylor tests were conducted on as-received OFHC Cu rod and ECAP specimens with sequential ECAP passes (2 and 8). The dynamic deformations of the samples are modeled using AUTODYN-2D and a modified Johnson-Cook constitutive equation was found to capture the dynamic response. Similar to the compression test results, the impacted front of the samples were found to recrystallize extensively and preferentially.

  5. Dispersion strengthened copper

    DOEpatents

    Sheinberg, Haskell; Meek, Thomas T.; Blake, Rodger D.

    1990-01-01

    A composition of matter comprised of copper and particles which are dispersed throughout the copper, where the particles are comprised of copper oxide and copper having a coating of copper oxide, and a method for making this composition of matter.

  6. Dispersion strengthened copper

    DOEpatents

    Sheinberg, Haskell; Meek, Thomas T.; Blake, Rodger D.

    1989-01-01

    A composition of matter comprised of copper and particles which are dispersed throughout the copper, where the particles are comprised of copper oxide and copper having a coating of copper oxide, and a method for making this composition of matter.

  7. Copper Metallochaperones

    PubMed Central

    Robinson, Nigel J.; Winge, Dennis R.

    2014-01-01

    The current state of knowledge on how copper metallochaperones support the maturation of cuproproteins is reviewed. Copper is needed within mitochondria to supply the CuA and intramembrane CuB sites of cytochrome oxidase, within the trans-Golgi network to supply secreted cuproproteins and within the cytosol to supply superoxide dismutase 1 (Sod1). Subpopulations of copper-zinc superoxide dismutase also localize to mitochondria, the secretory system, the nucleus and, in plants, the chloroplast, which also requires copper for plastocyanin. Prokaryotic cuproproteins are found in the cell membrane and in the periplasm of gram-negative bacteria. Cu(I) and Cu(II) form tight complexes with organic molecules and drive redox chemistry, which unrestrained would be destructive. Copper metallochaperones assist copper in reaching vital destinations without inflicting damage or becoming trapped in adventitious binding sites. Copper ions are specifically released from copper metallochaperones upon contact with their cognate cuproproteins and metal transfer is thought to proceed by ligand substitution. PMID:20205585

  8. Performance of a Cryogenic 21 Meter-Path Copper Herriott Cell Vacuum Coupled to a Bruker 125HR System

    NASA Astrophysics Data System (ADS)

    Mantz, Arlan W.; Sung, Keeyoon; Crawford, Timothy J.; Yu, Shanshan; Brown, Linda R.; Smith, Mary Ann H.; Devi, V. Malathy; Benner, D. Chris

    2013-06-01

    Accurate modeling of planetary atmospheres requires a detailed knowledge of the temperature and pressure dependence of spectroscopic line parameters of atmospheric molecules. With this requirement in mind, a new Herriott cell having a 21 meter folded absorption path was designed and fabricated with Oxygen-Free High Conductivity (OFHC) copper body and gold coated OFHC copper mirrors to operate for the first time with a broad-band Fourier transform spectrometer. The cell, enclosed in an isolated vacuum box, is cooled by a CTI Cryogenics, Inc. model 1050 closed-cycle helium refrigerator which also cryopumps the vacuum box. The temperature of the cell is monitored by a silicon temperature sensor and regulated by a Lakeshore model 331 temperature controller. The new cell system was integrated to the JPL Bruker model 125HR interferometer with transfer optics which are fully evacuated to 12 mTorr (the pressure inside the interferometer). The optics were through-put matched for entrance apertures smaller than 2 mm. The system has successfully operated for several months at gas sample temperatures between 75 and 250 K with extremely good stability to obtain spectra of methane, carbon dioxide, and oxygen bands between 0.76 and 3 μm. We present the characterization and performance of the Herriott cell system and preliminary analyses of newly recorded spectra. Research described in this paper was performed at Connecticut College, the Jet Propulsion Laboratory, California Institute of Technology, NASA Langley Research Center, and The College of William and Mary under contracts and cooperative agreements with the National Aeronautics and Space Administration.

  9. Modeling and evaluation of HE driven shock effects in copper with the MTS model

    SciTech Connect

    Murphy, M.J.; Lassila, D.F.

    1997-03-17

    Many experimental studies have investigated the effect of shock pressure on the post-shock mechanical properties of OFHC copper. These studies have shown that significant hardening occurs during shock loading due to dislocation processes and twinning. It has been demonstrated that when an appropriate initial value of the Mechanical Threshold Stress (MTS) is specified, the post-shock flow stress of OFE copper is well described by relationships derived independently for unshocked materials. In this study we consider the evolution of the MTS during HE driven shock loading processes and the effect on the subsequent flow stress of the copper. An increased post shock flow stress results in a higher material temperature due to an increase in the plastic work. An increase in temperature leads to thermal softening which reduces the flow stress. These coupled effects will determine if there is melting in a shaped charge jet or a necking instability in an EFP Ww. `Me critical factor is the evolution path followed combined with the `current` temperature, plastic strain, and strain rate. Preliminary studies indicate that in simulations of HE driven shock with very high resolution zoning, the MTS saturates because of the rate dependence in the evolution law. On going studies are addressing this and other issues with the goal of developing a version of the MT`S model that treats HE driven, shock loading, temperature, strain, and rate effects apriori.

  10. The evolution of damage in tritium exposed copper

    SciTech Connect

    Goods, S.H. )

    1991-02-01

    Severe microstructural damage has been observed in polycrystalline OFHC copper specimens thermally exposed to high pressure tritium gas at temperatures {le}200 {degree}C, but not at 300 {degree}C. No such damage occurs in single crystal specimens exposed under identical conditions, regardless of temperature. In the polycrystals, the damage takes the form of very flat, crack-like intergranular cavities. It is found that the cavitation evolves slowly with time. For short exposure times, cavities as small as 0.1 {mu}m are observed. In specimens subjected to the longest aging times, the cavities grow and link until entire grain boundary facets fail. The driving force for the growth of these cavities is attributed to the internal gas pressure of helium-3 generated by the decay of tritium. The growth kinetics of cavity microstructure are described by a coupled grain boundary, surface self-diffusion process. The tritium exposure profoundly affects the mechanical properties of the polycrystalline material, inducing a severe loss in ductility. In concert with the observed ductility loss is a change in fracture morphology from transgranular ductile rupture to intergranular fracture. Examination of the resulting grain boundary facets reveals a dimple structure. The spacing of these dimples can be correlated with the spacing of the exposure-induced grain boundary cavities.

  11. Oxidation of Copper Alloy Candidates for Rocket Engine Applications

    NASA Technical Reports Server (NTRS)

    Ogbuji, Linus U. Thomas; Humphrey, Donald L.

    2002-01-01

    The gateway to affordable and reliable space transportation in the near future remains long-lived rocket-based propulsion systems; and because of their high conductivities, copper alloys remain the best materials for lining rocket engines and dissipating their enormous thermal loads. However, Cu and its alloys are prone to oxidative degradation -- especially via the ratcheting phenomenon of blanching, which occurs in situations where the local ambient can oscillate between oxidation and reduction, as it does in a H2/02- fuelled rocket engine. Accordingly, resistance to blanching degradation is one of the key requirements for the next generation of reusable launch vehicle (RLV) liner materials. Candidate copper alloys have been studied with a view to comparing their oxidation behavior, and hence resistance to blanching, in ambients corresponding to conditions expected in rocket engine service. These candidate materials include GRCop-84 and GRCop-42 (Cu - Cr-8 - Nb-4 and Cu - Cr-4 - Nb-2 respectively); NARloy-Z (Cu-3%Ag-0.5%Y), and GlidCop (Cu-O.l5%Al2O3 ODS alloy); they represent different approaches to improving the mechanical properties of Cu without incurring a large drop in thermal conductivity. Pure Cu (OFHC-Cu) was included in the study to provide a baseline for comparison. The samples were exposed for 10 hours in the TGA to oxygen partial pressures ranging from 322 ppm to 1.0 atmosphere and at temperatures of up to 700 C, and examined by SEM-EDS and other techniques of metallography. This paper will summarize the results obtained.

  12. Interaction of atomic oxygen with thin film and bulk copper: An XPS, AES, XRD, and profilometer study

    NASA Technical Reports Server (NTRS)

    Raikar, Genesh N.; Gregory, John C.; Christl, Ligia C.; Peters, Palmer N.

    1992-01-01

    The University of Alabama in Huntsville (UAH) experiment A-0114 was designed primarily to study degradation of material surfaces due to low earth orbital (LEO) atmospheric oxygen. The experiment contained 128 one inch circular samples: metals, polymers, carbons, and semiconductors. Among metal samples, copper has shown some interesting new results. Two types of copper samples, a film sputter coated on fused silica and a bulk piece of OFHC copper, were characterized employing a variety of techniques such as X-ray and Auger electron spectroscopies, X-ray diffraction, and high resolution profilometry. Cu 2p core level spectra were used to characterize the presence of Cu2O and CuO in addition to Cu Auger LMM lines. These results are supported by our recent X-ray diffraction studies which clearly establish the presence of Cu oxides which we were unable to prove in our earlier work. Profilometry showed an increase in thickness of the film sample where exposed to 106.7 +/- 0.5 nm from an initial thickness of 74.2 +/- 1.1 nm. Further studies with SEM and ellipsometry are underway.

  13. Copper cyanide

    Integrated Risk Information System (IRIS)

    Copper cyanide ; CASRN 544 - 92 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Ef

  14. Dispersion strengthened copper

    DOEpatents

    Sheinberg, H.; Meek, T.T.; Blake, R.D.

    1990-01-09

    A composition of matter is described which is comprised of copper and particles which are dispersed throughout the copper, where the particles are comprised of copper oxide and copper having a coating of copper oxide. A method for making this composition of matter is also described. This invention relates to the art of powder metallurgy and, more particularly, it relates to dispersion strengthened metals.

  15. Copper peroxide

    NASA Technical Reports Server (NTRS)

    Moser, L.

    1988-01-01

    A number of oxidizing agents, including chlorine, bromine, ozone and other peroxides, were allowed to act on copper solutions with the intention of forming copper peroxide. The only successful agent appears to be hydrogen peroxide. It must be used in a neutral 50 to 30 percent solution at a temperature near zero. Other methods described in the literature apparently do not work. The excess of hydrogen must be quickly sucked out of the brown precipitate, which it is best to wash with alcohol and ether. The product, crystalline under a microscope, can be analyzed only approximately. It approaches the formula CuO2H2O. In alkaline solution it appears to act catalytically in causing the decomposition of other peroxides, so that Na2O2 cannot be used to prepare it. On the addition of acids the H2O2 is regenerated. The dry substance decomposes much more slowly than the moist but is not very stable.

  16. COPPER CORROSION RESEARCH UPDATE

    EPA Science Inventory

    Copper release and corrosion related issues continue to be important to many water systems. The objective of this presentation is to discuss the current state of copper research at the USEPA. Specifically, the role of aging on copper release, use of phosphates for copper corrosio...

  17. Copper and copper proteins in Parkinson's disease.

    PubMed

    Montes, Sergio; Rivera-Mancia, Susana; Diaz-Ruiz, Araceli; Tristan-Lopez, Luis; Rios, Camilo

    2014-01-01

    Copper is a transition metal that has been linked to pathological and beneficial effects in neurodegenerative diseases. In Parkinson's disease, free copper is related to increased oxidative stress, alpha-synuclein oligomerization, and Lewy body formation. Decreased copper along with increased iron has been found in substantia nigra and caudate nucleus of Parkinson's disease patients. Copper influences iron content in the brain through ferroxidase ceruloplasmin activity; therefore decreased protein-bound copper in brain may enhance iron accumulation and the associated oxidative stress. The function of other copper-binding proteins such as Cu/Zn-SOD and metallothioneins is also beneficial to prevent neurodegeneration. Copper may regulate neurotransmission since it is released after neuronal stimulus and the metal is able to modulate the function of NMDA and GABA A receptors. Some of the proteins involved in copper transport are the transporters CTR1, ATP7A, and ATP7B and the chaperone ATOX1. There is limited information about the role of those biomolecules in the pathophysiology of Parkinson's disease; for instance, it is known that CTR1 is decreased in substantia nigra pars compacta in Parkinson's disease and that a mutation in ATP7B could be associated with Parkinson's disease. Regarding copper-related therapies, copper supplementation can represent a plausible alternative, while copper chelation may even aggravate the pathology.

  18. Copper and Copper Proteins in Parkinson's Disease

    PubMed Central

    Rivera-Mancia, Susana; Diaz-Ruiz, Araceli; Tristan-Lopez, Luis; Rios, Camilo

    2014-01-01

    Copper is a transition metal that has been linked to pathological and beneficial effects in neurodegenerative diseases. In Parkinson's disease, free copper is related to increased oxidative stress, alpha-synuclein oligomerization, and Lewy body formation. Decreased copper along with increased iron has been found in substantia nigra and caudate nucleus of Parkinson's disease patients. Copper influences iron content in the brain through ferroxidase ceruloplasmin activity; therefore decreased protein-bound copper in brain may enhance iron accumulation and the associated oxidative stress. The function of other copper-binding proteins such as Cu/Zn-SOD and metallothioneins is also beneficial to prevent neurodegeneration. Copper may regulate neurotransmission since it is released after neuronal stimulus and the metal is able to modulate the function of NMDA and GABA A receptors. Some of the proteins involved in copper transport are the transporters CTR1, ATP7A, and ATP7B and the chaperone ATOX1. There is limited information about the role of those biomolecules in the pathophysiology of Parkinson's disease; for instance, it is known that CTR1 is decreased in substantia nigra pars compacta in Parkinson's disease and that a mutation in ATP7B could be associated with Parkinson's disease. Regarding copper-related therapies, copper supplementation can represent a plausible alternative, while copper chelation may even aggravate the pathology. PMID:24672633

  19. Explosive Welding of Aluminum, Titanium and Zirconium to Copper Sheet Metal

    NASA Technical Reports Server (NTRS)

    Hegazy, A. A.; Mote, J. D.

    1985-01-01

    The main material properties affecting the explosive weldability of a certain metal combination are the yield strength, the ductility, the density and the sonic velocity of the two metals. Successful welding of the metal combination depends mainly on the correct choice of the explosive welding parameters; i.e., the stand off distance, the weight of the explosive charge relative to the weight of the flyer plate and the detonation velocity of the explosive. Based on the measured and the handbook values of the properties of interest, the explosive welding parameters were calculated and the arrangements for the explosive welding of the Al alloy 6061-T6, titanium and zirconium to OFHC copper were determined. The relatively small sheet metal thickness (1/8") and the fact that the thickness of the explosive layer must exceed a certain minimum value were considered during the determination of the explosive welding conditions. The results of the metallographic investigations and the measurements of the shear strength at the interface demonstrate the usefulness of these calculations to minimize the number of experimental trials.

  20. The analysis of beryllium-copper diffusion joint after HHF test

    SciTech Connect

    Guiniatouline, R.N.; Mazul, I.V.; Rubkin, S.Y.

    1995-09-01

    The development of beryllium-copper joints which can withstand to relevant ITER divertor conditions is one of the important tasks at present time. One of the main problem for beryllium-copperjoints, is the inter-metallic layers, the strength and life time of joints significantly depends from the width and contents of the intermetallic layers. The objective of this work is to study the diffusion joint of TGP-56 beryllium to OFHC copper after thermal response and thermocyclic tests with beryllium-copper mockup. The BEY test were performed at e-beam facility (EBTS, SNLA). The following methods were used for analyses: the roentgenographic analysis; X-ray spectrum analysis; the fracture graphic analysis. During the investigation the followed studies were done: the analysis of diffusion boundary Be-Cu, which was obtained at the crossection of one of the tiles, the analysis of the debonded surfaces of a few beryllium tiles and corresponding copper parts; the analysis of upper surface of one of the tiles after HHF tests. The results of this work have showed that: the joint roentgenographic and elements analyses indicated the following phases in the diffusion zone: Cu{sub 2}Be ({approximately}170 {mu}m), CuBe ({approximately}30{mu}m), CuBe{sub 2} ({approximately}1 {mu}m) and solid solution of copper in beryllium. The phases Cu{sub 2}Be, CuBe and solid solution of copper in beryllium were indicated using quantitative microanalysis and phases CuBe, CuBe{sub 2}, Cu, Be - by roentgenographic analysis; the source of fracture (initial crack) is located in the central part of the tiles, the crack caused by the influence of residual stresses during cooling of a mock-up after fabrication and developed under the conditions of slow elastic-plastic growing during the process of thermal fatigue testing. The analysis gives the important data about joint`s quality and also may be used for any type of joints and its comparison for ITER applications.

  1. Copper-tantalum alloy

    DOEpatents

    Schmidt, Frederick A.; Verhoeven, John D.; Gibson, Edwin D.

    1986-07-15

    A tantalum-copper alloy can be made by preparing a consumable electrode consisting of an elongated copper billet containing at least two spaced apart tantalum rods extending longitudinally the length of the billet. The electrode is placed in a dc arc furnace and melted under conditions which co-melt the copper and tantalum to form the alloy.

  2. Demystifying Controlling Copper Corrosion

    EPA Science Inventory

    The LCR systematically misses the highest health and corrosion risk sites for copper. Additionally, there are growing concerns for WWTP copper in sludges and discharge levels. There are many corrosion control differences between copper and lead. This talk explains the sometimes c...

  3. [Copper IUDs (author's transl)].

    PubMed

    Thiery, M

    1983-10-01

    Following initial development of the Grafenberg ring in the 1920's, IUDs fell into disuse until the late 1950s, when plastic devices inserted using new technology began to gain worldwide acceptance. Further research indicated that copper had a significant antifertility effect which increased with increasing surface area, and several copper IUDs were developed and adapted, including the Copper T 200, the Copper T 220C, and the Copper T 380 A, probably the most effective yet. The Gravigard and Multiload are 2 other copper devices developed according to somewhat different principles. Copper devices are widely used not so much because of their great effectiveness as because of their suitability for nulliparous patients and their ease of insertion, which minimizes risk of uterine perforation. Records of 2584 women using Copper IUDs for 7190 women-years and 956 women using devices without copper for 6059 women-years suggest that the copper devices were associated with greater effectiveness and fewer removals for complications. Research suggests that the advantages of copper IUDs become more significant with increased duration of use. Contraindications to copper devices include allergy to copper and hepatolenticular degeneration. No carcinogenic or teratogenic effect of copper devices has been found, but further studies are needed to rule out other undesirable effects. Significant modifications of copper devices in recent years have been developed to increase their effectiveness, prolong their duration of usefulness, facilitate insertion and permit insertion during abortion or delivery. The upper limit of the surface area of copper associated with increased effectiveness appears to be between 200-300 sq mm, and at some point increases in copper exposure may provoke expulsion of the IUD. The duration of fertility inhibition of copper IUDs is usually estimated at 2-3 years, but recent research indicates that it may be 6-8 years, and some devices may retain copper surface

  4. Acute copper toxicity following copper glycinate injection.

    PubMed

    Oon, S; Yap, C-H; Ihle, B U

    2006-11-01

    We present a patient who developed multi-organ failure due to severe copper toxicity following attempted suicide by s.c. injection of copper glycinate. Acute copper toxicity is rare in the developed world, although it occurs more frequently in developing world countries, where it is a common mode of suicide. Acute toxicity usually results from oral ingestion and there are several local and systemic effects. Specific management can be difficult as there is little evidence regarding the efficacy of chelating agents in acute toxicity.

  5. Tritium migration to the surfaces of Type 316 stainless steel; aluminum 6061; and oxygen-free, high-conductivity copper

    DOE PAGES

    Sharpe, M.; Shmayda, W. T.; Schroder, W. U.

    2016-05-25

    The migration of tritium to the surfaces of aluminum 6061, oxygen-free, high-conductivity copper (OFHC), and stainless-steel 316 from the bulk metal was studied using low-pressure Tonks–Langmuir argon plasma. The plasma is shown to be effective at removing tritium from metal surfaces in a controlled manner. Tritium is removed in decreasing quantities with successive plasma exposures, which suggests a depletion of the surface and near-surface tritium inventories. A diffusion model was developed to predict tritium migration from the bulk and its accumulation in the water layers present on the metal surface. The model reproduces the rate of tritium re-growth on themore » surface for all three metals and can be used to calculate the triton solubility in the water layers present on metal surfaces. The ratio of surface-to-bulk solubilities at the water-layer/bulk-metal interface uniquely determines the concentration ratio between these two media. Removing the tritium-rich water layers induces tritium to migrate from the bulk to the surface. Furthermore, this process is driven by a concentration gradient that develops in the bulk because of the perturbation on the surface.« less

  6. Tritium migration to the surfaces of Type 316 stainless steel; aluminum 6061; and oxygen-free, high-conductivity copper

    SciTech Connect

    Sharpe, M.; Shmayda, W. T.; Schroder, W. U.

    2016-05-25

    The migration of tritium to the surfaces of aluminum 6061, oxygen-free, high-conductivity copper (OFHC), and stainless-steel 316 from the bulk metal was studied using low-pressure Tonks–Langmuir argon plasma. The plasma is shown to be effective at removing tritium from metal surfaces in a controlled manner. Tritium is removed in decreasing quantities with successive plasma exposures, which suggests a depletion of the surface and near-surface tritium inventories. A diffusion model was developed to predict tritium migration from the bulk and its accumulation in the water layers present on the metal surface. The model reproduces the rate of tritium re-growth on the surface for all three metals and can be used to calculate the triton solubility in the water layers present on metal surfaces. The ratio of surface-to-bulk solubilities at the water-layer/bulk-metal interface uniquely determines the concentration ratio between these two media. Removing the tritium-rich water layers induces tritium to migrate from the bulk to the surface. Furthermore, this process is driven by a concentration gradient that develops in the bulk because of the perturbation on the surface.

  7. Copper in developmental stuttering.

    PubMed

    Alm, Per A

    2005-01-01

    It has previously been reported that men with developmental stuttering showed reduced concentration of copper in the blood, and a negative correlation between the copper level and the severity of stuttering. Disorders of copper metabolism may result in dysfunction of the basal ganglia system and dystonia, a motor disorder sharing some traits of stuttering. It has been shown that copper ions affect the dopamine and the GABA systems. With this background we investigated the plasma level of copper, the copper binding protein ceruloplasmin, and the estimated level of free copper in stuttering adults. Sixteen men with developmental stuttering were compared with 16 men without speech problems. The samples were assayed in one batch in a pseudorandom and counterbalanced order. No significant differences were found between stuttering men and the control group in any of the biological variables, and no negative correlation between copper and the general severity of stuttering was shown. On the contrary, an explorative analysis resulted in a positive correlation between high plasma copper and superfluous muscular activity during stuttering (r=0.51, p=0.04). This result indicates that there is no relation between developmental stuttering and low plasma copper in the main population of stuttering adults.

  8. Handling of Copper and Copper Oxide Nanoparticles by Astrocytes.

    PubMed

    Bulcke, Felix; Dringen, Ralf

    2016-02-01

    Copper is an essential trace element for many important cellular functions. However, excess of copper can impair cellular functions by copper-induced oxidative stress. In brain, astrocytes are considered to play a prominent role in the copper homeostasis. In this short review we summarise the current knowledge on the molecular mechanisms which are involved in the handling of copper by astrocytes. Cultured astrocytes efficiently take up copper ions predominantly by the copper transporter Ctr1 and the divalent metal transporter DMT1. In addition, copper oxide nanoparticles are rapidly accumulated by astrocytes via endocytosis. Cultured astrocytes tolerate moderate increases in intracellular copper contents very well. However, if a given threshold of cellular copper content is exceeded after exposure to copper, accelerated production of reactive oxygen species and compromised cell viability are observed. Upon exposure to sub-toxic concentrations of copper ions or copper oxide nanoparticles, astrocytes increase their copper storage capacity by upregulating the cellular contents of glutathione and metallothioneins. In addition, cultured astrocytes have the capacity to export copper ions which is likely to involve the copper ATPase 7A. The ability of astrocytes to efficiently accumulate, store and export copper ions suggests that astrocytes have a key role in the distribution of copper in brain. Impairment of this astrocytic function may be involved in diseases which are connected with disturbances in brain copper metabolism.

  9. Copper-Silicon Bronzes

    DTIC Science & Technology

    1933-05-11

    copper alloys which have good static properties are disa:cinting in their endurance properties. The silicide allo~rs that are given high tensile strength...notched endurance tests and on cast alloys of this type, are lacking. uowever, preliminary reports state that a copper beryllium alloy of about 2 1/2...properties re- main almost the same. Grain size increases with sil- icon. III A study of hardening copper by heat treating its alloys with silicides

  10. Hair copper in intrauterine copper device users.

    PubMed

    Thiery, M; Heyndrickx, A; Uyttersprot, C

    1984-03-01

    The antifertility effect of copper-bearing IUDs is based on continuous release of copper, which is a result of the reaction between the metal and the uterine secretions. Released cupric ions collect in the endometrium and in the uterine fluid but significant accumulation has not been found in the bloodstream or elsewhere. Following Laker's suggestion that hair be used for monitoring essential trace elements, e.g., copper, we checked the copper content of the hair of women wearing copper-bearing IUDs. Samples of untreated pubic hair removed by clipping before diagnostic curettage were obtained from 10 young (24-34 years old), white caucasian females who until then had been wearing an MLCu250 IUD for more than 1 year. Pubes from 10 comparable (sex, age, race) subjects who had never used a Cu-containing device served as controls. The unwashed material was submitted to the toxicology laboratory, where the copper content was assessed by flameless atomic absorption, a technique whose lower limit of measurement lies at a concentration of 0.05 mcg Cu/ml fluid (50 ppb). Hair samples were washed to remove extraneous traces of metal according to the prescriptions of the International Atomic Energy Agency, weighed, and mineralized, after which a small volume (10 mcl) of the diluted fluid was fed into the graphite furnace. Each sample (75-150 mg) was analyzed 4 times, both before and after washing. Since the cleaning procedure reduces the weight of the sample (mainly by the removal of fat, dust, etc.) this explains why the percentage copper content of washed hair is higher than that of unwashed hair belonging to the same subject. The results indicate that there was no significant difference (Mann-Whitney U test) between the mean copper levels of both unwashed and washed pubes from women who were using or had never used an MLCu250 IUD. We therefore conclude that the use of this copper-containing device is not associated with significant accumulation of copper in (pubic) hair.

  11. Biogenic nanoparticles: copper, copper oxides, copper sulphides, complex copper nanostructures and their applications.

    PubMed

    Rubilar, Olga; Rai, Mahendra; Tortella, Gonzalo; Diez, Maria Cristina; Seabra, Amedea B; Durán, Nelson

    2013-09-01

    Copper nanoparticles have been the focus of intensive study due to their potential applications in diverse fields including biomedicine, electronics, and optics. Copper-based nanostructured materials have been used in conductive films, lubrification, nanofluids, catalysis, and also as potent antimicrobial agent. The biogenic synthesis of metallic nanostructured nanoparticles is considered to be a green and eco-friendly technology since neither harmful chemicals nor high temperatures are involved in the process. The present review discusses the synthesis of copper nanostructured nanoparticles by bacteria, fungi, and plant extracts, showing that biogenic synthesis is an economically feasible, simple and non-polluting process. Applications for biogenic copper nanoparticles are also discussed.

  12. High adherence copper plating process

    DOEpatents

    Nignardot, Henry

    1993-01-01

    A process for applying copper to a substrate of aluminum or steel by electrodeposition and for preparing an aluminum or steel substrate for electrodeposition of copper. Practice of the invention provides good adhesion of the copper layer to the substrate.

  13. Copper-containing zeolite catalysts

    DOEpatents

    Price, Geoffrey L.; Kanazirev, Vladislav

    1996-01-01

    A catalyst useful in the conversion of nitrogen oxides or in the synthesis of nitriles or imines from amines, formed by preparing an intimate mechanical mixture of a copper (II)-containing species, such as CuO or CuCl.sub.2, or elemental copper, with a zeolite having a pore mouth comprising 10 oxygen atoms, such as ZSM-5, converting the elemental copper or copper (II) to copper (I), and driving the copper (I) into the zeolite.

  14. Copper-containing zeolite catalysts

    DOEpatents

    Price, G.L.; Kanazirev, V.

    1996-12-10

    A catalyst useful in the conversion of nitrogen oxides or in the synthesis of nitriles or imines from amines, is formed by preparing an intimate mechanical mixture of a copper (II)-containing species, such as CuO or CuCl{sub 2}, or elemental copper, with a zeolite having a pore mouth comprising 10 oxygen atoms, such as ZSM-5, converting the elemental copper or copper (II) to copper (I), and driving the copper (I) into the zeolite.

  15. Improved Electroformed Structural Copper and Copper Alloys

    NASA Technical Reports Server (NTRS)

    Malone, G. A.; Hudson, W.; Babcock, B.; Edwards, R.

    1998-01-01

    Electroforming offers a superior means for fabricating internally cooled heat exchangers and structures subjected to thermal environments. Copper is deposited from many such applications because of the good thermal conductivity. It suffers from mediocre yield strength as a structural material and loses mechanical strength at intermediate temperatures. Mechanical properties similar to those of electroformed nickel are desired. Phase 1 examined innovative means to improve deposited copper structural performance. Yield strengths as high as 483 MPa (70 ksi) were obtained with useful ductility while retaining a high level of purity essential to good thermal conductivity. Phase 2 represents a program to explore new additive combinations in copper electrolytes to produce a more fine, equiaxed grain which can be thermally stabilized by other techniques such as alloying in modest degrees and dispersion strengthening. Evaluation of new technology - such as the codeposition of fullerness (diamond-like) particles were made to enhance thermal conductivity in low alloys. A test fire quality tube-bundle engine was fabricated using these copper property improvement concepts to show the superiority of the new coppers and fabrications methods over competitive technologies such as brazing and plasma deposition.

  16. COPPER RESEARCH UPDATE

    EPA Science Inventory

    This presentation provides an update and overview of new research results and remaining research needs with respect to copper corrosion control issues. The topics to be covered include: occurrence of elevated copper release in systems that meet the Action Level; impact of water c...

  17. Green Luminescent Copper Nanoparticles

    NASA Astrophysics Data System (ADS)

    Suresh, Y.; Annapurna, S.; Bhikshamaiah, G.; Singh, A. K.

    2016-09-01

    Copper nanoparticles are synthesized by a green chemical reduction method using Gum Kondagogu extract as stabilizer. The as-prepared powder samples are characterized by Transmission Electron Microscopy (TEM), Small Angle X-Ray Scattering (SAXS), UV-Visible Spectroscopy, X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) techniques. The as-prepared copper nanoparticles are found to be FCC crystalline and nearly monodispersed with particles size 19 nm. Photoluminescence (PL) measurement showed strong green visible emission and PL intensity was found enhanced with the presence of natural extract on copper nanoparticle surface. The increase in the PL intensity was mainly due to copper nanoparticles. Photoluminescence spectra of copper nanoparticles show an emission peak at 430 nm when illuminated at 325 nm.

  18. Bioaccessibility and Solubility of Copper in Copper-Treated Lumber

    EPA Science Inventory

    Micronized copper (MC)-treated lumber is a recent replacement for Chromated Copper Arsenate (CCA) and Ammonium Copper (AC)-treated lumbers; though little is known about the potential risk of copper (Cu) exposure from incidental ingestion of MC-treated wood. The bioaccessibility o...

  19. Killing of bacteria by copper surfaces involves dissolved copper.

    PubMed

    Molteni, Cristina; Abicht, Helge K; Solioz, Marc

    2010-06-01

    Bacteria are rapidly killed on copper surfaces. However, the mechanism of this process remains unclear. Using Enterococcus hirae, the effect of inactivation of copper homeostatic genes and of medium compositions on survival and copper dissolution was tested. The results support a role for dissolved copper ions in killing.

  20. Fabricating Copper Nanotubes by Electrodeposition

    NASA Technical Reports Server (NTRS)

    Yang, E. H.; Ramsey, Christopher; Bae, Youngsam; Choi, Daniel

    2009-01-01

    Copper tubes having diameters between about 100 and about 200 nm have been fabricated by electrodeposition of copper into the pores of alumina nanopore membranes. Copper nanotubes are under consideration as alternatives to copper nanorods and nanowires for applications involving thermal and/or electrical contacts, wherein the greater specific areas of nanotubes could afford lower effective thermal and/or electrical resistivities. Heretofore, copper nanorods and nanowires have been fabricated by a combination of electrodeposition and a conventional expensive lithographic process. The present electrodeposition-based process for fabricating copper nanotubes costs less and enables production of copper nanotubes at greater rate.

  1. Micromachining with copper lasers

    NASA Astrophysics Data System (ADS)

    Knowles, Martyn R. H.; Bell, Andy; Foster-Turner, Gideon; Rutterford, Graham; Chudzicki, J.; Kearsley, Andrew J.

    1997-04-01

    In recent years the copper laser has undergone extensive development and has emerged as a leading and unique laser for micromachining. The copper laser is a high average power (10 - 250 W), high pulse repetition rate (2 - 32 kHz), visible laser (511 nm and 578 nm) that produces high peak power (typically 200 kW), short pulses (30 ns) and very good beam quality (diffraction limited). This unique set of laser parameters results in exceptional micro-machining in a wide variety of materials. Typical examples of the capabilities of the copper laser include the drilling of small holes (10 - 200 micrometer diameter) in materials as diverse as steel, ceramic, diamond and polyimide with micron precision and low taper (less than 1 degree) cutting and profiling of diamond. Application of the copper laser covers the electronic, aerospace, automotive, nuclear, medical and precision engineering industries.

  2. Volatility of copper

    SciTech Connect

    Palmer, D.A.; Simonson, J.M.; Joyce, D.B.

    1996-08-01

    The relevant aqueous thermodynamics of copper and its oxides are evaluated and summarized with emphasis on solubility, hydrolysis, and complexation. The solubilities of metallic copper, solid cuprous and cupric oxides in steam measured by Pocock and Stewart in 1963 are discussed and the latter data are fitted in the form of established empirical equations and compared to other existing results. No other sources of data were found for the solubility of copper and cupric oxide in steam and even these data are very limited. Discussion of corresponding available solubility data on both oxide phases in liquid water is given. The possible effects of complexing agents are considered. A brief discussion is provided of the role of surface adsorption in determining the fate of dissolved copper in the boiler. 37 refs., 5 figs., 3 tabs.

  3. Bacterial Killing by Dry Metallic Copper Surfaces▿

    PubMed Central

    Santo, Christophe Espírito; Lam, Ee Wen; Elowsky, Christian G.; Quaranta, Davide; Domaille, Dylan W.; Chang, Christopher J.; Grass, Gregor

    2011-01-01

    Metallic copper surfaces rapidly and efficiently kill bacteria. Cells exposed to copper surfaces accumulated large amounts of copper ions, and this copper uptake was faster from dry copper than from moist copper. Cells suffered extensive membrane damage within minutes of exposure to dry copper. Further, cells removed from copper showed loss of cell integrity. Acute contact with metallic copper surfaces did not result in increased mutation rates or DNA lesions. These findings are important first steps for revealing the molecular sensitive targets in cells lethally challenged by exposure to copper surfaces and provide a scientific explanation for the use of copper surfaces as antimicrobial agents for supporting public hygiene. PMID:21148701

  4. Copper and copper-nickel alloys as zebra mussel antifoulants

    SciTech Connect

    Dormon, J.M.; Cottrell, C.M.; Allen, D.G.; Ackerman, J.D.; Spelt, J.K.

    1996-04-01

    Copper has been used in the marine environment for decades as cladding on ships and pipes to prevent biofouling by marine mussels (Mytilus edulis L.). This motivated the present investigation into the possibility of using copper to prevent biofouling in freshwater by both zebra mussels and quagga mussels (Dreissena polymorpha and D. bugensis collectively referred to as zebra mussels). Copper and copper alloy sheet proved to be highly effective in preventing biofouling by zebra mussels over a three-year period. Further studies were conducted with copper and copper-nickel mesh (lattice of expanded metal) and screen (woven wire with a smaller hole size), which reduced the amount of copper used. Copper screen was also found to be strongly biofouling-resistant with respect to zebra mussels, while copper mesh reduced zebra mussel biofouling in comparison to controls, but did not prevent it entirely. Preliminary investigations into the mechanism of copper antifouling, using galvanic couples, indicated that the release of copper ions from the surface of the exposed metal into the surrounding water is directly or indirectly responsible for the biofouling resistance of copper.

  5. Preparation of high purity copper fluoride by fluorinating copper hydroxyfluoride

    NASA Technical Reports Server (NTRS)

    King, R. B.; Lundquist, J. R.

    1969-01-01

    Copper fluoride containing no more than 50 ppm of any contaminating element was prepared by the fluorination of copper hydroxyfluoride. The impurity content was obtained by spark source mass spectrometry. High purity copper fluoride is needed as a cathode material for high energy density batteries.

  6. 24-hour urine copper test

    MedlinePlus

    ... associated with providing a urine sample. Alternative Names Quantitative urinary copper Images Copper urine test References McPherson ... for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis ...

  7. Agricultural soils spiked with copper mine wastes and copper concentrate: implications for copper bioavailability and bioaccumulation.

    PubMed

    Ginocchio, Rosanna; Sánchez, Pablo; de la Fuente, Luz María; Camus, Isabel; Bustamante, Elena; Silva, Yasna; Urrestarazu, Paola; Torres, Juan C; Rodríguez, Patricio H

    2006-03-01

    A better understanding of exposure to and effects of copper-rich pollutants in soils is required for accurate environmental risk assessment of copper. A greenhouse experiment was conducted to study copper bioavailability and bioaccumulation in agricultural soils spiked with different types of copper-rich mine solid wastes (copper ore, tailing sand, smelter dust, and smelter slag) and copper concentrate. A copper salt (copper sulfate, CuSO4) that frequently is used to assess soil copper bioavailability and phytotoxicity also was included for comparison. Results showed that smelter dust, tailing sand, and CuSO4 are more likely to be bioavailable and, thus, toxic to plants compared with smelter slag, concentrate, and ore at equivalent total copper concentrations. Differences may be explained by intrinsic differences in copper solubilization from the source materials, but also by their capability to decrease soil pH (confounding effect). The copper toxicity and bioaccumulation in plants also varied according to soil physicochemical characteristics (e.g., pH and total organic carbon) and the available levels of plant nutrients, such as nitrogen, phosphorus, and potassium. Chemistry/mineralogy of mine materials, soil/pore-water chemistry, and plant physiological status thus should be integrated for building adequate models to predict phytotoxicity and environmental risk of copper.

  8. Copper-phosphorus alloys offer advantages in brazing copper

    SciTech Connect

    Rupert, W.D.

    1996-05-01

    Copper-phosphorus brazing alloys are used extensively for joining copper, especially refrigeration and air-conditioning copper tubing and electrical conductors. What is the effect of phosphorus when alloyed with copper? The following are some of the major effects: (1) It lowers the melt temperature of copper (a temperature depressant). (2) It increases the fluidity of the copper when in the liquid state. (3) It acts as a deoxidant or a fluxing agent with copper. (4) It lowers the ductility of copper (embrittles). There is a misconception that silver improves the ductility of the copper-phosphorus alloys. In reality, silver added to copper acts in a similar manner as phosphorus. The addition of silver to copper lowers the melt temperature (temperature depressant) and decreases the ductility. Fortunately, the rate and amount at which silver lowers copper ductility is significantly less than that of phosphorus. Therefore, taking advantage of the temperature depressant property of silver, a Ag-Cu-P alloy can be selected at approximately the same melt temperature as a Cu-P alloy, but at a lower phosphorus content. The lowering of the phosphorus content actually makes the alloy more ductile, not the silver addition. A major advantage of the copper-phosphorus alloys is the self-fluxing characteristic when joining copper to copper. They may also be used with the addition of a paste flux on brass, bronze, and specialized applications on silver, tungsten and molybdenum. Whether it is selection of the proper BCuP alloy or troubleshooting an existing problem, the suggested approach is a review of the desired phosphorus content in the liquid metal and how it is being altered during application. In torch brazing, a slight change in the oxygen-fuel ratio can affect the joint quality or leak tightness.

  9. High adherence copper plating process

    DOEpatents

    Nignardot, H.

    1993-09-21

    A process is described for applying copper to a substrate of aluminum or steel by electrodeposition and for preparing the surface of an aluminum or steel substrate for the electrodeposition of copper. Practice of the invention provides good adhesion of the copper layer to either substrate.

  10. Brazing copper to dispersion-strengthened copper

    SciTech Connect

    Ryding, D.G.; Allen, D.; Lee, R.

    1996-08-01

    The Advanced Photon Source (APS) is a state-of-the-art synchrotron light source that will produce intense x-ray beams, which will allow the study of smaller samples and faster reactions and processes at a greater level of detail that has been possible to date. The beam is produced by using third-generation insertion devices in a 7 GeV electron/positron storage ring that is 1100 meters in circumference. The heat load from these intense high power devices is very high and certain components must sustain total heat loads of 3 to 15 kW and heat fluxes of 30 W/mm{sup 2}. Because the beams will cycle on and off many times, thermal shock and fatigue will be a problem. High heat flux impinging on a small area causes a large thermal gradient that results in high stress. GlidCop{reg_sign}, a dispersion strengthened copper, is the desired material because of its high thermal conductivity and superior mechanical properties as compared to copper and its alloys. GlidCop is not amenable to joining by fusion welding, and brazing requires diligence because of high diffusivity. Brazing procedures were developed using optical and scanning electron microscopy.

  11. Precursors for formation of copper selenide, indium selenide, copper indium diselenide, and/or copper indium gallium diselenide films

    DOEpatents

    Curtis, Calvin J; Miedaner, Alexander; Van Hest, Maikel; Ginley, David S

    2014-11-04

    Liquid-based precursors for formation of Copper Selenide, Indium Selenide, Copper Indium Diselenide, and/or copper Indium Galium Diselenide include copper-organoselenides, particulate copper selenide suspensions, copper selenide ethylene diamine in liquid solvent, nanoparticulate indium selenide suspensions, and indium selenide ethylene diamine coordination compounds in solvent. These liquid-based precursors can be deposited in liquid form onto substrates and treated by rapid thermal processing to form crystalline copper selenide and indium selenide films.

  12. Creative Copper Crests

    ERIC Educational Resources Information Center

    Knab, Thomas

    2011-01-01

    In this article, the author discusses how to create an art activity that would link the computer-created business cards of fourth-grade students with an upcoming school-wide medieval event. Creating family crests from copper foil would be a great connection, since they, like business cards, are an individual's way to identify themselves to others.…

  13. Production of ultrahigh purity copper using waste copper nitrate solution.

    PubMed

    Choi, J Y; Kim, D S

    2003-04-25

    The production of ultrahigh purity copper (99.9999%) by electrolysis in the presence of a cementation barrier has been attempted employing a waste nitric copper etching solution as the electrolyte. The amount of copper deposited on the cathode increased almost linearly with electrolysis time and the purity of copper was observed to increase as the electrolyte concentration was increased. At some point, however, as the electrolyte concentration increased, the purity of copper decreased slightly. As the total surface area of cementation barrier increased, the purity of product increased. The electrolyte temperature should be maintained below 35 degrees C in the range of investigated electrolysis conditions to obtain the ultrahigh purity copper. Considering that several industrial waste solutions contain valuable metallic components the result of present study may support a claim that electrowinning is a very desirable process for their treatment and recovery.

  14. Copper Vapor Generator

    DTIC Science & Technology

    1974-09-01

    percent measured during this program in a static copper vapor apparatus developed at PIB . This efficiency has been calculated by dividing the energy of a... laser medium. A measure of beam quality may be defined in terms ot the energy delivered in the tar field in relatum to the energy delivered by a...phase of the work the homogeneity requirements for the medium of a high -power laser was reviewed. These requirements were translated into measurable

  15. Oxidation Mechanism of Copper Selenide

    NASA Astrophysics Data System (ADS)

    Taskinen, Pekka; Patana, Sonja; Kobylin, Petri; Latostenmaa, Petri

    2014-09-01

    The oxidation mechanism of copper selenide was investigated at deselenization temperatures of copper refining anode slimes. The isothermal roasting of synthetic, massive copper selenide in flowing oxygen and oxygen - 20% sulfur dioxide mixtures at 450-550 °C indicate that in both atmospheres the mass of Cu2Se increases as a function of time, due to formation of copper selenite as an intermediate product. Copper selenide oxidises to copper oxides without formation of thick copper selenite scales, and a significant fraction of selenium is vaporized as SeO2(g). The oxidation product scales on Cu2Se are porous which allows transport of atmospheric oxygen to the reaction zone and selenium dioxide vapor to the surrounding gas. Predominance area diagrams of the copper-selenium system, constructed for selenium roasting conditions, indicate that the stable phase of copper in a selenium roaster gas with SO2 is the sulfate CuSO4. The cuprous oxide formed in decomposition of Cu2Se is further sulfated to CuSO4.

  16. Copper corrosion in coastal Oregon

    SciTech Connect

    Ballard, Sophie J.; Cramer, Stephen D.; Covino, Bernard S. Jr.; Holcomb, Gordon R.

    1998-01-01

    The US Department of Energy is studying the atmospheric corrosion performance of copper and other metals along the Oregon coast. Only the copper results will be presented in this paper. Atmospheric corrosion measurements of copper samples were made at seven bridges, eight coastal communities, and three inland reference sites to quantify and understand the effect of high chloride environments on the corrosion performance of copper. The materials were atmospherically exposed for 1, 2, and 3 years to examine the effects of sheltering, orientation, distance from the ocean, and coastal microclimates on the rate of corrosion and the composition of the corrosion film.

  17. Removal of copper from ferrous scrap

    DOEpatents

    Blander, M.; Sinha, S.N.

    1990-05-15

    A process for removing copper from ferrous or other metal scrap in which the scrap is contacted with a polyvalent metal sulfide slag in the presence of an excess of copper-sulfide forming additive to convert the copper to copper sulfide which is extracted into the slag to provide a ratio of copper in the slag to copper in the metal scrap of at least about 10.

  18. Removal of copper from ferrous scrap

    DOEpatents

    Blander, M.; Sinha, S.N.

    1987-07-30

    A process for removing copper from ferrous or other metal scrap in which the scrap is contacted with a polyvalent metal sulfide slag in the presence of an excess of copper-sulfide forming additive to convert the copper to copper sulfide which is extracted into the slag to provide a ratio of copper in the slag to copper in the metal scrap of at least about 10.

  19. Removal of copper from ferrous scrap

    DOEpatents

    Blander, Milton; Sinha, Shome N.

    1990-01-01

    A process for removing copper from ferrous or other metal scrap in which the scrap is contacted with a polyvalent metal sulfide slag in the presence of an excess of copper-sulfide forming additive to convert the copper to copper sulfide which is extracted into the slag to provide a ratio of copper in the slag to copper in the metal scrap of at least about 10.

  20. Synthesis of copper/copper oxide nanoparticles by solution plasma

    NASA Astrophysics Data System (ADS)

    Saito, Genki; Hosokai, Sou; Tsubota, Masakatsu; Akiyama, Tomohiro

    2011-07-01

    This paper describes the synthesis of copper/copper oxide nanoparticles via a solution plasma, in which the effect of the electrolyte and electrolysis time on the morphology of the products was mainly examined. In the experiments, a copper wire as a cathode was immersed in an electrolysis solution of a K2CO3 with the concentration from 0.001 to 0.50 M or a citrate buffer (pH = 4.8), and was melted by the local-concentration of current. The results demonstrated that by using the K2CO3 solution, we obtained CuO nanoflowers with many sharp nanorods, the size of which decreased with decreasing the concentration of the solution. Spherical particles of copper with/without pores formed when the citrate buffer was used. The pores in the copper nanoparticles appeared when the applied voltage changed from 105 V to 130 V, due to the dissolution of Cu2O.

  1. Copper mediated carbometalation reactions.

    PubMed

    Müller, D S; Marek, I

    2016-08-08

    Since the first discovery of carbocupration of alkynes in the 1970s a tremendous amount of research has been carried out in this field. The exceptionally high selectivities obtained attribute to the great synthetic value of carbocupration reactions. This tutorial review will present the most important features of carbocupration of alkynes and highlight the most relevant reviews. Then a comprehensive review of copper mediated carbometalation of cyclopropenes will follow. The latter method has received much attention over the last decade as it allows the highly selective construction of poly-substituted cyclopropanes which can be transformed into acyclic derivatives bearing one or multiple tertiary or quaternary carbon stereocenters.

  2. Antimony activities in copper mattes

    NASA Astrophysics Data System (ADS)

    Hino, M.; Toguri, J. M.

    1987-03-01

    A mass spectrometric technique combined with a double Knudsen cell was used to determine the antimony and copper activities in the Cu-Sb binary system at 1373 K and in the two-melt composition range of the Cu-S-Sb ternary system at 1423 K. The antimony and copper activities were calculated based on the intensity ration of the gaseous Sb and Cu species, over the unknown and known activity samples, respectively. γ{Sb/o} were found to be 1.1×10-2 in molten copper at 1373 K, and 1.8×10-2 and 0.44 in a copper-rich phase and in a matter phase, of the Cu-S-Sb ternary system at 1423 K, respectively. These values indicate, that antimony can be removed during the matte smelting and slagging stage of the copper smelting process. Interaction parameters of antimony in molten copper slagging stage of the copper smelting process. Interaction parameters of antimony in molten copper at 1423 K were calculated and found to be 10.7, -5.4, and 6.3 for ɛ{Sb/Sb} · ρSb Sb, and ɛ{Sb/S}, respectively.

  3. Lead and Copper Control 101

    EPA Science Inventory

    This presentation is an overview of the most important water treatment strategies for the control of lead and copper release from drinking water corrosion. In addition to the sections specifically on lead and copper treatment, sections are included that cover sampling to find le...

  4. Effects of copper(II) and copper oxides on THMs formation in copper pipe.

    PubMed

    Li, Bo; Qu, Jiuhui; Liu, Huijuan; Hu, Chengzhi

    2007-08-01

    Little is known about how the growth of trihalomethanes (THMs) in drinking water is affected in copper pipe. The formation of THMs and chlorine consumption in copper pipe under stagnant flow conditions were investigated. Experiments for the same water held in glass bottles were performed for comparison. Results showed that although THMs levels firstly increased in the presence of chlorine in copper pipe, faster decay of chlorine as compared to the glass bottle affected the rate of THMs formation. The analysis of water phase was supplemented by surface analysis of corrosion scales using X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and energy dispersive spectroscopy (EDX). The results showed the scales on the pipe surface mainly consisted of Cu(2)O, CuO and Cu(OH)(2) or CuCO(3). Designed experiments confirmed that the fast depletion of chlorine in copper pipe was mainly due to effect of Cu(2)O, CuO in corrosion scales on copper pipe. Although copper(II) and copper oxides showed effect on THMs formation, the rapid consumption of chlorine due to copper oxide made THM levels lower than that in glass bottles after 4h. The transformations of CF, DCBM and CDBM to BF were accelerated in the presence of copper(II), cupric oxide and cuprous oxide. The effect of pH on THMs formation was influenced by effect of pH on corrosion of copper pipe. When pH was below 7, THMs levels in copper pipe was higher as compared to glass bottle, but lower when pH was above 7.

  5. Optical Properties of Copper Nanoparticles

    NASA Astrophysics Data System (ADS)

    Kalenskii, A. V.; Zvekov, A. A.; Nikitin, A. P.; Anan'eva, M. V.

    2015-12-01

    Spectral dependences of the light extinction, absorption, and scattering efficiency factors of copper nanoparticles attendant to variations of their radii are calculated. A plasmon maximum is observed on the spectral dependence of the extinction efficiency factor for nanoparticle radii 10-60 nm. The maximum of the absorption efficiency factor is shifted toward red wavelengths with increasing radius of copper nanoparticles. Results are interpreted based on the special features of the spectral dependence of the complex copper refractive index. It is shown that the copper nanoparticles with radius of 35 nm placed into a transparent matrix with refractive index of 1.54 (secondary explosive pentaerythritol tetranitrate) possess a very high value of the absorption efficiency factor (2.9) of the second harmonic of a neodymium laser. Our investigations suggest that the copper nanoparticles are perspective material for application in compositions for optical detonator capsules.

  6. Metabolism and functions of copper in brain.

    PubMed

    Scheiber, Ivo F; Mercer, Julian F B; Dringen, Ralf

    2014-05-01

    Copper is an important trace element that is required for essential enzymes. However, due to its redox activity, copper can also lead to the generation of toxic reactive oxygen species. Therefore, cellular uptake, storage as well as export of copper have to be tightly regulated in order to guarantee sufficient copper supply for the synthesis of copper-containing enzymes but also to prevent copper-induced oxidative stress. In brain, copper is of importance for normal development. In addition, both copper deficiency as well as excess of copper can seriously affect brain functions. Therefore, this organ possesses ample mechanisms to regulate its copper metabolism. In brain, astrocytes are considered as important regulators of copper homeostasis. Impairments of homeostatic mechanisms in brain copper metabolism have been associated with neurodegeneration in human disorders such as Menkes disease, Wilson's disease and Alzheimer's disease. This review article will summarize the biological functions of copper in the brain and will describe the current knowledge on the mechanisms involved in copper transport, storage and export of brain cells. The role of copper in diseases that have been connected with disturbances in brain copper homeostasis will also be discussed.

  7. 21 CFR 73.1647 - Copper powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Copper powder. 73.1647 Section 73.1647 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1647 Copper powder. (a) Identity. (1) The color additive copper powder is a very fine free-flowing metallic powder prepared from virgin electrolytic copper....

  8. 21 CFR 73.1647 - Copper powder.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Copper powder. 73.1647 Section 73.1647 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1647 Copper powder. (a) Identity. (1) The color additive copper powder is a very fine free-flowing metallic powder prepared from virgin electrolytic copper....

  9. 49 CFR 192.279 - Copper pipe.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Copper pipe. 192.279 Section 192.279 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... Copper pipe. Copper pipe may not be threaded except that copper pipe used for joining screw fittings...

  10. 49 CFR 192.279 - Copper pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Copper pipe. 192.279 Section 192.279 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... Copper pipe. Copper pipe may not be threaded except that copper pipe used for joining screw fittings...

  11. 21 CFR 73.1647 - Copper powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Copper powder. 73.1647 Section 73.1647 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1647 Copper powder. (a) Identity. (1) The color additive copper powder is a very fine free-flowing metallic powder prepared from virgin electrolytic copper....

  12. 21 CFR 184.1260 - Copper gluconate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Copper gluconate. 184.1260 Section 184.1260 Food... GRAS § 184.1260 Copper gluconate. (a) Copper gluconate (cupric gluconate (CH2OH(CHOH)4COO)2Cu, CAS Reg... ingredient is used in food at levels not to exceed current good manufacturing practice. Copper gluconate...

  13. 21 CFR 184.1260 - Copper gluconate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Copper gluconate. 184.1260 Section 184.1260 Food... Specific Substances Affirmed as GRAS § 184.1260 Copper gluconate. (a) Copper gluconate (cupric gluconate... practice. Copper gluconate may be used in infant formula in accordance with section 412(g) of the...

  14. 21 CFR 184.1260 - Copper gluconate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Copper gluconate. 184.1260 Section 184.1260 Food... Specific Substances Affirmed as GRAS § 184.1260 Copper gluconate. (a) Copper gluconate (cupric gluconate... practice. Copper gluconate may be used in infant formula in accordance with section 412(g) of the...

  15. 21 CFR 184.1260 - Copper gluconate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Copper gluconate. 184.1260 Section 184.1260 Food... Specific Substances Affirmed as GRAS § 184.1260 Copper gluconate. (a) Copper gluconate (cupric gluconate... practice. Copper gluconate may be used in infant formula in accordance with section 412(g) of the...

  16. 49 CFR 192.279 - Copper pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Copper pipe. 192.279 Section 192.279 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... Copper pipe. Copper pipe may not be threaded except that copper pipe used for joining screw fittings...

  17. 21 CFR 184.1260 - Copper gluconate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Copper gluconate. 184.1260 Section 184.1260 Food... Specific Substances Affirmed as GRAS § 184.1260 Copper gluconate. (a) Copper gluconate (cupric gluconate... practice. Copper gluconate may be used in infant formula in accordance with section 412(g) of the...

  18. 49 CFR 192.279 - Copper pipe.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Copper pipe. 192.279 Section 192.279 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... Copper pipe. Copper pipe may not be threaded except that copper pipe used for joining screw fittings...

  19. 21 CFR 73.1647 - Copper powder.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Copper powder. 73.1647 Section 73.1647 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1647 Copper powder. (a) Identity. (1) The color additive copper powder is a very fine free-flowing metallic powder prepared from virgin electrolytic copper....

  20. 49 CFR 192.279 - Copper pipe.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Copper pipe. 192.279 Section 192.279 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... Copper pipe. Copper pipe may not be threaded except that copper pipe used for joining screw fittings...

  1. Modeling Temperature and Strain Rate History Effects in OFHC Cu

    DTIC Science & Technology

    2007-11-02

    Temperature Histories Many experiments were conducted above room temperature. Three-zone furnaces and induction heaters were used to heat the specimens...ADIABATIC HEATING 338 XI VI.9: PARAMETER MATRIX 342 VI.10: RESPONSE MATRIX 343 VI.11: CORRELATION OF FACTOR AND PARAMETER 346 Xll LIST OF FIGURES...111.15: Hopkinson bar experiment setup at SNL. Induction heater coil and water cooling system are shown 59 111.16: Configuration of the modified

  2. Analysis on dynamic tensile extrusion behavior of UFG OFHC Cu

    NASA Astrophysics Data System (ADS)

    Park, Kyung-Tae; Park, Leeju; Kim, Hak Jun; Kim, Seok Bong; Lee, Chong Soo

    2014-08-01

    Dynamic tensile extrusion (DTE) tests with the strain rate order of ~105 s-1 were conducted on coarse grained (CG) Cu and ultrafine grained (UFG) Cu. ECAP of 16 passes with route Bc was employed to fabricate UFG Cu. DTE tests were carried out by launching the sphere samples to the conical extrusion die at a speed of ~475 m/sec in a vacuumed gas gun system. UFG Cu was fragmented into 3 pieces and showed a DTE elongation of ~340%. CG Cu exhibited a larger DTE elongation of ~490% with fragmentation of 4 pieces. During DTE tests, dynamic recrystallization occurred in UFG Cu, but not in CG Cu. In order to examine the DTE behavior of CG Cu and UFG Cu under very high strain rates, a numerical analysis was undertaken by using a commercial finite element code (LS-DYNA 2D axis-symmetric model) with the Johnson - Cook model. The numerical analysis correctly predicted fragmentation and DTE elongation of CG Cu. But, the experimental DTE elongation of UFG Cu was much smaller than that predicted by the numerical analysis. This difference is discussed in terms of microstructural evolution of UFG Cu during DTE tests.

  3. Selecting copper and copper alloys; Part 2: Cast products

    SciTech Connect

    Peters, D.T. ); Kundig, K.J.A. , Randolph, NJ )

    1994-06-01

    This article provides an introduction to the properties, characteristics, and applications of cast coppers and copper alloys. An overview of alloy families is presented since it is impractical to describe all 130 standard grades in detail. However, additional technical information is readily available from the Copper Development Assn. Inc. (CDA) and the resources listed in the references and bibliography at the end of the article. Copper casting alloys are primarily selected for either their corrosion resistance, or their combination of corrosion resistance and mechanical properties. The materials also feature good castability, high machinability, and, compared with other corrosion-resistant alloys, reasonable cost. Additional benefits include biofouling resistance--important in marine applications--and a spectrum of attractive colors. Many of the alloys also have favorable tribological properties, which explains their widespread use for sleeve bearings, wear plates, gears, and other wear-prone components.

  4. Interpulse kinetics in copper and copper halide lasers

    NASA Technical Reports Server (NTRS)

    Harstad, K. G.

    1983-01-01

    The various rate processes that govern the interpulse relaxation in metal vapor and metal halide vapor lasers are considered. Computer calculations indicate that the rapid metastable levels relaxation observed in copper and copper halide laser experiments requires the existence of a relatively small resonance in the cross section for metastable excitation or deexcitation near threshold. The accurate calculation of interpulse relaxation requires knowledge of rate constants presently not well known; this is especially so for metal halide lasers.

  5. Majorana Electroformed Copper Mechanical Analysis

    SciTech Connect

    Overman, Nicole R.; Overman, Cory T.; Kafentzis, Tyler A.; Edwards, Danny J.; Hoppe, Eric W.

    2012-04-30

    The MAJORANA DEMONSTRATOR is a large array of ultra-low background high-purity germanium detectors, enriched in 76Ge, designed to search for zero-neutrino double-beta decay. The DEMONSTRATOR will utilize ultra high purity electroformed copper for a variety of detector components and shielding. A preliminary mechanical evaluation was performed on the Majorana prototype electroformed copper material. Several samples were removed from a variety of positions on the mandrel. Tensile testing, optical metallography, scanning electron microscopy, and hardness testing were conducted to evaluate mechanical response. Analyses carried out on the Majorana prototype copper to this point show consistent mechanical response from a variety of test locations. Evaluation shows the copper meets or exceeds the design specifications.

  6. Formation of copper-indium-selenide and/or copper-indium-gallium-selenide films from indium selenide and copper selenide precursors

    DOEpatents

    Curtis, Calvin J [Lakewood, CO; Miedaner, Alexander [Boulder, CO; Van Hest, Maikel [Lakewood, CO; Ginley, David S [Evergreen, CO; Nekuda, Jennifer A [Lakewood, CO

    2011-11-15

    Liquid-based indium selenide and copper selenide precursors, including copper-organoselenides, particulate copper selenide suspensions, copper selenide ethylene diamine in liquid solvent, nanoparticulate indium selenide suspensions, and indium selenide ethylene diamine coordination compounds in solvent, are used to form crystalline copper-indium-selenide, and/or copper indium gallium selenide films (66) on substrates (52).

  7. Copper atomic-scale transistors

    PubMed Central

    Kavalenka, Maryna N; Röger, Moritz; Albrecht, Daniel; Hölscher, Hendrik; Leuthold, Jürgen

    2017-01-01

    We investigated copper as a working material for metallic atomic-scale transistors and confirmed that copper atomic-scale transistors can be fabricated and operated electrochemically in a copper electrolyte (CuSO4 + H2SO4) in bi-distilled water under ambient conditions with three microelectrodes (source, drain and gate). The electrochemical switching-on potential of the atomic-scale transistor is below 350 mV, and the switching-off potential is between 0 and −170 mV. The switching-on current is above 1 μA, which is compatible with semiconductor transistor devices. Both sign and amplitude of the voltage applied across the source and drain electrodes (U bias) influence the switching rate of the transistor and the copper deposition on the electrodes, and correspondingly shift the electrochemical operation potential. The copper atomic-scale transistors can be switched using a function generator without a computer-controlled feedback switching mechanism. The copper atomic-scale transistors, with only one or two atoms at the narrowest constriction, were realized to switch between 0 and 1G 0 (G 0 = 2e2/h; with e being the electron charge, and h being Planck’s constant) or 2G 0 by the function generator. The switching rate can reach up to 10 Hz. The copper atomic-scale transistor demonstrates volatile/non-volatile dual functionalities. Such an optimal merging of the logic with memory may open a perspective for processor-in-memory and logic-in-memory architectures, using copper as an alternative working material besides silver for fully metallic atomic-scale transistors. PMID:28382242

  8. Release of Micronized Copper Particles from Pressure ...

    EPA Pesticide Factsheets

    Micronized copper pressure treated lumber (PTL) has recently been introduced to the consumer market as a replacement for ionized copper PTL. The presence of particulate rather than aqueous copper raises concerns about the exposure of humans as well as the environment to the particles. Two common pathways of exposure, leaching during contact with water and transfer during physical contact, were investigated to gage potential human and environmental risk during intended use of the product. Characterization, leaching tests, and wipe tests were conducted on two representative formulations of micronized copper PTL (micronized copper azole or MCA) to quantify the levels of copper present in the treated material and the amount of copper released during use as well as to determine the form (particle or ion) of the copper after it was released. Additionally, an ionized copper pressure treated wood (alkaline copper azole or ACA) was tested for comparison. The characterization showed that copper carbonate is the primary particle form in the MCA treated wood, but other forms are also present, particularly in the MCA-1 formulation, which contained a large amount of organically complexed copper. Microscopy showed that MCA-1 contained particles roughly half the size of MCA-2. The leaching results indicate that mostly (> ~95%) ionic copper is released from the MCA wood and that the particulate copper that was released is attached to cellulose and not free in solution. A sma

  9. Copper status of ewes fed increasing amounts of copper from copper sulfate or copper proteinate.

    PubMed

    Eckert, G E; Greene, L W; Carstens, G E; Ramsey, W S

    1999-01-01

    The Cu status of mature, crossbred ewes fed two sources (CuSO4 vs. Cu proteinate) and three levels (10, 20, or 30 mg/kg) of dietary Cu was determined in a 73-d feeding trial. Ewes (n = 30) were fed a basal diet containing rice meal feed, cottonseed hulls, cottonseed meal, meat and bone meal, cracked corn, and vitamin-mineral supplements at 2.5% of BW to meet NRC requirements for protein, energy, macrominerals, and microminerals, excluding Cu. The basal diet contained 5 mg/kg Cu, 113 mg/kg Fe, .1 mg/kg Mo, and .17% S. Copper sulfate or Cu proteinate was added to the basal diet to supply 10, 20, or 30 mg/kg of dietary copper in a 2x3 factorial arrangement of treatments. Ewes were housed in 3.7- x 9.1-m pens in an open-sided barn. Blood samples were collected on d 28 and 73. Ewes were slaughtered on d 74, and liver and other tissues were collected to determine Cu concentrations. An interaction (P = .08) occurred between source and level for liver Cu. The interaction existed due to an increase in liver Cu concentrations when ewes were fed increasing dietary Cu from CuSO4 but not when fed Cu proteinate diets. There was no source x level interaction (P>.10) for the blood constituents measured. On d 73, plasma ceruloplasmin activity was greater (P<.05) in ewes fed Cu proteinate than in those fed CuSO4 (33.1 vs. 26.8 microM x min(-1) x L(-1)). Increasing the concentration of dietary Cu did not affect (P>.10) plasma ceruloplasmin. Packed cell volume (PCV), red blood cell count (RBC), white blood cell count, whole blood hemoglobin (wHb), plasma hemoglobin, and plasma Cu were similar between sources of Cu. Ewes fed 20 mg/kg Cu had lower (P<.05) PCV, RBC, and wHb than those fed 10 or 30 mg/kg Cu diets. Feeding up to 30 mg/kg Cu from these sources did not cause an observable Cu toxicity during the 73-d period.

  10. Genes involved in copper resistance influence survival of Pseudomonas aeruginosa on copper surfaces

    PubMed Central

    Elguindi, Jutta; Wagner, Janine; Rensing, Christopher

    2013-01-01

    Aims To evaluate the killing of Pseudomonas aeruginosa PAO1 on copper cast alloys and the influence of genes on survival on copper containing medium and surfaces. Methods and Results Different strains of P. aeruginosa were inoculated on copper containing medium or different copper cast alloys and the survival rate determined. The survival rates were compared to rates on copper-free medium and stainless steel as control. In addition, the effect of temperature on survival was examined. Conclusions Copper cast alloys had previously shown to be bactericidal to various bacteria but the mechanism of copper-mediated killing is still not known. In this report we demonstrate that P. aeruginosa PAO1 is rapidly killed on different copper cast alloys and that genes involved in conferring copper resistance in copper-containing medium also influenced survival on copper cast alloys. We also show that the rate of killing is influenced by temperature. PMID:19239551

  11. Process Of Bonding Copper And Tungsten

    DOEpatents

    Slattery, Kevin T.; Driemeyer, Daniel E.; Davis, John W.

    2000-07-18

    Process for bonding a copper substrate to a tungsten substrate by providing a thin metallic adhesion promoting film bonded to a tungsten substrate and a functionally graded material (FGM) interlayer bonding the thin metallic adhesion promoting film to the copper substrate. The FGM interlayer is formed by sintering a stack of individual copper and tungsten powder blend layers having progressively higher copper content/tungsten content, by volume, ratio values in successive powder blend layers in a lineal direction extending from the tungsten substrate towards the copper substrate. The resulting copper to tungsten joint well accommodates the difference in the coefficient of thermal expansion of the materials.

  12. Biliary copper excretion by hepatocyte lysosomes in the rat. Major excretory pathway in experimental copper overload

    SciTech Connect

    Gross, J.B. Jr.; Myers, B.M.; Kost, L.J.; Kuntz, S.M.; LaRusso, N.F.

    1989-01-01

    We investigated the hypothesis that lysosomes are the main source of biliary copper in conditions of hepatic copper overload. We used a rat model of oral copper loading and studied the relationship between the biliary output of copper and lysosomal hydrolases. Male Sprague-Dawley rats were given tap water with or without 0.125% copper acetate for up to 36 wk. Copper loading produced a 23-fold increase in the hepatic copper concentration and a 30-65% increase in hepatic lysosomal enzyme activity. Acid phosphatase histochemistry showed that copper-loaded livers contained an increased number of hepatocyte lysosomes; increased copper concentration of these organelles was confirmed directly by both x ray microanalysis and tissue fractionation. The copper-loaded rats showed a 16-fold increase in biliary copper output and a 50-300% increase in biliary lysosomal enzyme output. In the basal state, excretory profiles over time were similar for biliary outputs of lysosomal enzymes and copper in the copper-loaded animals but not in controls. After pharmacologic stimulation of lysosomal exocytosis, biliary outputs of copper and lysosomal hydrolases in the copper-loaded animals remained coupled: injection of colchicine or vinblastine produced an acute rise in the biliary output of both lysosomal enzymes and copper to 150-250% of baseline rates. After these same drugs, control animals showed only the expected increase in lysosomal enzyme output without a corresponding increase in copper output. We conclude that the hepatocyte responds to an increased copper load by sequestering excess copper in an increased number of lysosomes that then empty their contents directly into bile. The results provide direct evidence that exocytosis of lysosomal contents into biliary canaliculi is the major mechanism for biliary copper excretion in hepatic copper overload.

  13. 21 CFR 73.2125 - Potassium sodium copper chlorophyllin (chlorophyllin-copper complex).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Potassium sodium copper chlorophyllin (chlorophyllin-copper complex). 73.2125 Section 73.2125 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... § 73.2125 Potassium sodium copper chlorophyllin (chlorophyllin-copper complex). (a) Identity...

  14. 21 CFR 73.2125 - Potassium sodium copper chlorophyllin (chlorophyllin-copper complex).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Potassium sodium copper chlorophyllin (chlorophyllin-copper complex). 73.2125 Section 73.2125 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... § 73.2125 Potassium sodium copper chlorophyllin (chlorophyllin-copper complex). (a) Identity...

  15. 21 CFR 73.1125 - Potassium sodium copper chloropyhllin (chlorophyllin-copper complex).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Potassium sodium copper chloropyhllin (chlorophyllin-copper complex). 73.1125 Section 73.1125 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT....1125 Potassium sodium copper chloropyhllin (chlorophyllin-copper complex). (a) Identity. (1) The...

  16. 21 CFR 73.1125 - Potassium sodium copper chloropyhllin (chlorophyllin-copper complex).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Potassium sodium copper chloropyhllin (chlorophyllin-copper complex). 73.1125 Section 73.1125 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT....1125 Potassium sodium copper chloropyhllin (chlorophyllin-copper complex). (a) Identity. (1) The...

  17. 21 CFR 73.2125 - Potassium sodium copper chlorophyllin (chlorophyllin-copper complex).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Potassium sodium copper chlorophyllin (chlorophyllin-copper complex). 73.2125 Section 73.2125 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... § 73.2125 Potassium sodium copper chlorophyllin (chlorophyllin-copper complex). (a) Identity...

  18. 21 CFR 73.2125 - Potassium sodium copper chlorophyllin (chlorophyllin-copper complex).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Potassium sodium copper chlorophyllin (chlorophyllin-copper complex). 73.2125 Section 73.2125 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... § 73.2125 Potassium sodium copper chlorophyllin (chlorophyllin-copper complex). (a) Identity...

  19. 21 CFR 73.2125 - Potassium sodium copper chlorophyllin (chlorophyllin-copper complex).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Potassium sodium copper chlorophyllin (chlorophyllin-copper complex). 73.2125 Section 73.2125 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... § 73.2125 Potassium sodium copper chlorophyllin (chlorophyllin-copper complex). (a) Identity...

  20. 21 CFR 73.1125 - Potassium sodium copper chloropyhllin (chlorophyllin-copper complex).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Potassium sodium copper chloropyhllin (chlorophyllin-copper complex). 73.1125 Section 73.1125 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT....1125 Potassium sodium copper chloropyhllin (chlorophyllin-copper complex). (a) Identity. (1) The...

  1. Leaching of Copper Ore by Thiobacillus Ferrooxidans.

    ERIC Educational Resources Information Center

    Lennox, John; Biaha, Thomas

    1991-01-01

    A quantitative laboratory exercise based upon the procedures copper manufacturers employ to increase copper production is described. The role of chemoautotrophic microorganisms in biogeologic process is emphasized. Safety considerations when working with bacteria are included. (KR)

  2. Thermotransport in liquid aluminum-copper alloys

    NASA Technical Reports Server (NTRS)

    Bhat, B. N.

    1973-01-01

    A thermotransport study was made on a series of liquid aluminum-copper alloys which contained from trace amounts to 33 weight percent copper. The samples in the form of narrow capillaries were held in known temperature gradient of thermotransport apparatus until the stationary state was reached. The samples were analyzed for the concentration of copper along the length. Copper was observed to migrate to the colder regions in all the samples. The heat of transport, Q*, was determined for each composition from a plot of concentration of copper versus reciprocal absolute temperature. The value of Q* is the highest at trace amounts of copper (4850 cal/gm-atom), but decreases with increasing concentration of copper and levels off to 2550 cal/gm-atom at about 25 weight percent copper. The results are explained on the basis of electron-solute interaction and a gas model of diffusion.

  3. Molecular Mediators Governing Iron-Copper Interactions

    PubMed Central

    Gulec, Sukru; Collins, James F.

    2015-01-01

    Given their similar physiochemical properties, it is a logical postulate that iron and copper metabolism are intertwined. Indeed, iron-copper interactions were first documented over a century ago, but the homeostatic effects of one on the other has not been elucidated at a molecular level to date. Recent experimental work has, however, begun to provide mechanistic insight into how copper influences iron metabolism. During iron deficiency, elevated copper levels are observed in the intestinal mucosa, liver, and blood. Copper accumulation and/or redistribution within enterocytes may influence iron transport, and high hepatic copper may enhance biosynthesis of a circulating ferroxidase, which potentiates iron release from stores. Moreover, emerging evidence has documented direct effects of copper on the expression and activity of the iron-regulatory hormone hepcidin. This review summarizes current experimental work in this field, with a focus on molecular aspects of iron-copper interplay and how these interactions relate to various disease states. PMID:24995690

  4. Copper tolerance and virulence in bacteria

    PubMed Central

    Ladomersky, Erik; Petris, Michael J.

    2015-01-01

    Copper (Cu) is an essential trace element for all aerobic organisms. It functions as a cofactor in enzymes that catalyze a wide variety of redox reactions due to its ability to cycle between two oxidation states, Cu(I) and Cu(II). This same redox property of copper has the potential to cause toxicity if copper homeostasis is not maintained. Studies suggest that the toxic properties of copper are harnessed by the innate immune system of the host to kill bacteria. To counter such defenses, bacteria rely on copper tolerance genes for virulence within the host. These discoveries suggest bacterial copper intoxication is a component of host nutritional immunity, thus expanding our knowledge of the roles of copper in biology. This review summarizes our current understanding of copper tolerance in bacteria, and the extent to which these pathways contribute to bacterial virulence within the host. PMID:25652326

  5. Placental copper transport in the brindled mouse

    SciTech Connect

    Garnica, A.; Bates, J.

    1986-03-01

    Pregnant brindled (brin) mice were injected at 16 or 19 days gestation with 2 doses of CuCl/sub 2/ 6 mcg/g/dose, separated by 12 h, and sacrificed 6 h after the second. The copper conc. in placenta (P) and kidneys (K) of uninjected (UI) brin mice were higher than in UI controls, while conc. in liver (L) and fetal carcass (F) were lower. After injection (I), placental copper conc. increased while the carcass conc. remained unchanged. Brin mouse is a model for the human inborn error of copper metabolism, Menkes syndrome, which is characterized by signs of copper deficiency. These data indicate that metabolism of copper in brin fetus is abnormal, but depressed fetal copper levels cannot be corrected by acute copper dosing because of the sequestration of copper in placenta.

  6. Copper tolerance and virulence in bacteria.

    PubMed

    Ladomersky, Erik; Petris, Michael J

    2015-06-01

    Copper (Cu) is an essential trace element for all aerobic organisms. It functions as a cofactor in enzymes that catalyze a wide variety of redox reactions due to its ability to cycle between two oxidation states, Cu(I) and Cu(II). This same redox property of copper has the potential to cause toxicity if copper homeostasis is not maintained. Studies suggest that the toxic properties of copper are harnessed by the innate immune system of the host to kill bacteria. To counter such defenses, bacteria rely on copper tolerance genes for virulence within the host. These discoveries suggest bacterial copper intoxication is a component of host nutritional immunity, thus expanding our knowledge of the roles of copper in biology. This review summarizes our current understanding of copper tolerance in bacteria, and the extent to which these pathways contribute to bacterial virulence within the host.

  7. Application of saccharose as copper(II) ligand for electroless copper plating solutions.

    PubMed

    Norkus, Eugenijus; Prusinskas, Kestutis; Vaskelis, Algirdas; Jaciauskiene, Jane; Stalnioniene, Irena; Macalady, Donald L

    2007-01-15

    Saccharose, forming sufficiently stable complexes with copper(II) ions in alkaline solutions, was found to be a suitable ligand for copper(II) chelating in alkaline (pH>12) electroless copper deposition solutions. Reduction of copper(II)-saccharose complexes by hydrated formaldehyde was investigated and the copper deposits formed were characterized. The thickness of the compact copper coatings obtained under optimal operating conditions in 1h reaches ca. 2 microm at ambient temperature. The plating solutions were stable and no signs of Cu(II) reduction in the bulk solution were observed. Results were compared with those systems operating with other copper(II) ligands.

  8. Textured carbon surfaces on copper by sputtering

    NASA Technical Reports Server (NTRS)

    Curren, A. N. (Inventor); Jensen, K. A. (Inventor); Roman, R. F. (Inventor)

    1986-01-01

    A very thin layer of highly textured carbon is applied to a copper surface by a triode sputtering process. A carbon target and a copper substrate are simultaneously exposed to an argon plasma in a vacuum chamber. The resulting carbon surface is characterized by a dense, random array of needle like spires or peaks which extend perpendicularly from the copper surface. The coated copper is especially useful for electrode plates in multistage depressed collectors.

  9. 21 CFR 184.1261 - Copper sulfate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Copper sulfate. 184.1261 Section 184.1261 Food and... Substances Affirmed as GRAS § 184.1261 Copper sulfate. (a) Copper sulfate (cupric sulfate, CuSO4·5H2O, CAS... the reaction of sulfuric acid with cupric oxide or with copper metal. (b) The ingredient must be of...

  10. 21 CFR 184.1261 - Copper sulfate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Copper sulfate. 184.1261 Section 184.1261 Food and... Substances Affirmed as GRAS § 184.1261 Copper sulfate. (a) Copper sulfate (cupric sulfate, CuSO4·5 H2O, CAS... the reaction of sulfuric acid with cupric oxide or with copper metal. (b) The ingredient must be of...

  11. 21 CFR 184.1261 - Copper sulfate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Copper sulfate. 184.1261 Section 184.1261 Food and....1261 Copper sulfate. (a) Copper sulfate (cupric sulfate, CuSO4·5 H2O, CAS Reg. No. 7758-99-8) usually... sulfuric acid with cupric oxide or with copper metal. (b) The ingredient must be of a purity suitable...

  12. 21 CFR 184.1261 - Copper sulfate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Copper sulfate. 184.1261 Section 184.1261 Food and... Substances Affirmed as GRAS § 184.1261 Copper sulfate. (a) Copper sulfate (cupric sulfate, CuSO4·5H2O, CAS... the reaction of sulfuric acid with cupric oxide or with copper metal. (b) The ingredient must be of...

  13. 21 CFR 184.1261 - Copper sulfate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Copper sulfate. 184.1261 Section 184.1261 Food and... Substances Affirmed as GRAS § 184.1261 Copper sulfate. (a) Copper sulfate (cupric sulfate, CuSO4·5 H2O, CAS... the reaction of sulfuric acid with cupric oxide or with copper metal. (b) The ingredient must be of...

  14. Copper Post-CMP Cleaning

    NASA Astrophysics Data System (ADS)

    Starosvetsky, D.; Ein-Eli, Y.

    Copper on-chip interconnects Damascene technology utilizes chemical mechanical polishing (CMP) in order to remove copper overburden after its electro deposition and achieve global planarization of patterned surface. CMP is a simultaneous action of mechanical overburden metal removal and its electrochemical dissolution. It is performed with the movement of a polisher pad in acidic or alkaline aqueous CMP electrolytes (slurry) containing dispersive abrasive particles (Al2O3 or SiO2), pH buffer, certain electrolyte salts to control ionic strength, oxidants, and corrosion inhibitors. Mechanical and chemical interactions with a patterned wafer surface introduce different defects and contaminations in interlayer dielectric (ILD) surfaces and copper layers. These can either be mechanical (physical) or chemical-based defects and contaminants [1-6].

  15. The copper microRNAs.

    PubMed

    Pilon, Marinus

    2017-02-01

    1030 I. 1030 II. 1030 III. 1031 IV. 1031 V. 1032 VI. 1033 VII. 1034 VIII. 1034 1034 References 1034 SUMMARY: Copper (Cu) microRNAs are upregulated by Cu deficiency and mediate the post-transcriptional downregulation of transcripts that encode Cu proteins, suggesting a role directly related to Cu. However, expression and phenotypic analyses of copper microRNA mutants and over-expressors have suggested roles mainly in tolerance to abiotic stresses. To reconcile available data, a model is proposed which emphasizes the mobile nature of copper microRNA molecules in the regulation of Cu homeostasis. It is proposed that the Cu-microRNA regulatory circuits are further co-opted by plants to regulate both beneficial and pathogenic interactions with microbes. Further exploration of Cu-microRNA functions that account for the cell-to-cell mobility should give novel insight into plant microbe interactions and the integration of micronutrition and development.

  16. Contribution of Copper Ion Resistance to Survival of Escherichia coli on Metallic Copper Surfaces▿

    PubMed Central

    Santo, Christophe Espírito; Taudte, Nadine; Nies, Dietrich H.; Grass, Gregor

    2008-01-01

    Bacterial contamination of touch surfaces poses a serious threat for public health. The use of bactericidal surface materials, such as copper and its alloys, might constitute a way to aid the use of antibiotics and disinfectants, thus minimizing the risk of emergence and spread of multiresistant germs. The survival of Escherichia coli on metallic copper surfaces has been studied previously; however, the mechanisms underlying bacterial inactivation on copper surfaces have not been elucidated. Data presented in this study suggest that bacteria are killed rapidly on dry copper surfaces. Several factors, such as copper ion toxicity, copper chelators, cold, osmotic stress, and reactive oxygen species, but not anaerobiosis, influenced killing rates. Strains deleted in copper detoxification systems were slightly more sensitive than was the wild type. Preadaptation to copper enhanced survival rates upon copper surface exposure. This study constitutes a first step toward understanding the reasons for metallic copper surface-mediated killing of bacteria. PMID:18156321

  17. THE EVOLUTION OF SYNTHETICALLY PRECIPITATED COPPER SOLIDS

    EPA Science Inventory

    The objective of this study was to explore the effect of water quality, particularly chloride and sulfate, on copper mineral formation. Copper-sulfate and chloride compounds are often found on the surface of copper pipes in drinking water distribution systems. When attempting to ...

  18. 21 CFR 73.2647 - Copper powder.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Copper powder. 73.2647 Section 73.2647 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2647 Copper powder. (a) Identity and specifications. The color additive copper powder shall conform in identity and specifications to the requirements of §...

  19. 21 CFR 524.463 - Copper naphthenate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Copper naphthenate. 524.463 Section 524.463 Food... DRUGS, FEEDS, AND RELATED PRODUCTS OPHTHALMIC AND TOPICAL DOSAGE FORM NEW ANIMAL DRUGS § 524.463 Copper naphthenate. (a) Amount. The drug is a 37.5 percent solution of copper naphthenate. (b) Sponsors. See...

  20. 21 CFR 524.463 - Copper naphthenate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Copper naphthenate. 524.463 Section 524.463 Food... DRUGS, FEEDS, AND RELATED PRODUCTS OPHTHALMIC AND TOPICAL DOSAGE FORM NEW ANIMAL DRUGS § 524.463 Copper naphthenate. (a) Amount. The drug is a 37.5 percent solution of copper naphthenate. (b) Sponsors. See...

  1. 21 CFR 73.2647 - Copper powder.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Copper powder. 73.2647 Section 73.2647 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2647 Copper powder. (a) Identity and specifications. The color additive copper powder shall conform in identity and specifications to the requirements of §...

  2. 21 CFR 73.2647 - Copper powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Copper powder. 73.2647 Section 73.2647 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2647 Copper powder. (a) Identity and specifications. The color additive copper powder shall conform in identity and specifications to the requirements of §...

  3. Copper toxicity in aquaculture: A practical approach

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Copper sulfate is used as a therapeutant for various applications in aquaculture. There is a great deal of information on the toxicity of copper, especially in low-alkalinity waters; however, much of this information is fragmented, and a comprehensive guide of copper toxicity and safe concentration...

  4. 21 CFR 73.2647 - Copper powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Copper powder. 73.2647 Section 73.2647 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2647 Copper powder. (a) Identity and specifications. The color additive copper powder shall conform in identity and specifications to the requirements of §...

  5. 21 CFR 73.2647 - Copper powder.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Copper powder. 73.2647 Section 73.2647 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2647 Copper powder. (a) Identity and specifications. The color additive copper powder shall conform in identity and specifications to the requirements of §...

  6. 21 CFR 524.463 - Copper naphthenate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Copper naphthenate. 524.463 Section 524.463 Food... DRUGS, FEEDS, AND RELATED PRODUCTS OPHTHALMIC AND TOPICAL DOSAGE FORM NEW ANIMAL DRUGS § 524.463 Copper naphthenate. (a) Amount. The drug is a 37.5 percent solution of copper naphthenate. (b) Sponsors. See...

  7. 21 CFR 524.463 - Copper naphthenate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Copper naphthenate. 524.463 Section 524.463 Food... DRUGS, FEEDS, AND RELATED PRODUCTS OPHTHALMIC AND TOPICAL DOSAGE FORM NEW ANIMAL DRUGS § 524.463 Copper naphthenate. (a) Amount. The drug is a 37.5 percent solution of copper naphthenate. (b) Sponsors. See...

  8. Measuring bioavailable copper using anodic stripping voltammetry

    SciTech Connect

    Deaver, E.; Rodgers, J.H. Jr.

    1996-11-01

    Since speciation can affect bioavailability and toxicity of copper in aquatic systems, accurate predictions of effects of bioavailable forms require detection and/or measurement of these forms. To develop an approach for measurement of bioavailable copper, a copper sulfate solution was used in 10-d aqueous and sediment toxicity tests with Hyalella azteca Saussure. These tests encompassed ranges of pH, alkalinity, hardness, and conductivity. Changes in copper speciation were measured using atomic absorption spectroscopy (AA) for dissolved copper and differential pulse anodic stripping voltammetry (DPASV) for labile copper, and concentrations were evaluated relative to amphipod survival. Ten-day LC50s based on AA-measured aqueous copper concentrations ranged from 42 to 142 {micro}g Cu/L, and LC50s based on DPASV-measured copper concentrations ranged from 17.4 to 24.8 {micro}g Cu/L. In 10-d tests using copper-amended sediments with diverse characteristics and AA-measured copper concentrations spanning an order of magnitude, total copper concentrations were not predictive of sediment toxicity, but H. azteca survival was explained by DPASV measurements that varied by {le}4%. In order to make defensible estimates of the potential risk of metals in sediments or water, it is essential to identify the fraction of total metal that is bioavailable. In these experiments, DPASV was useful for measuring bioavailable copper in aqueous and sediment tests with H. azteca.

  9. Copper accumulation in the crayfish (Orconectes rusticus)

    SciTech Connect

    Evans, M.L.

    1980-06-01

    The purpose of this study was to determine whether or not the crayfish, O. rusticus could fulfill Nehring's (1976) criteria for a good biological monitor of heavy metal pollution. Since there is some evidence that the cupric ion is the most toxic form of aqueous copper, crayfish-accumulated copper was compared to both total and cupric copper in the culture water.

  10. Relationship between soil copper content and copper content of selected crop plants in central Chile.

    PubMed

    Badilla-Ohlbaum, R; Ginocchio, R; Rodríguez, P H; Céspedes, A; González, S; Allen, H E; Lagos, G E

    2001-12-01

    A survey of copper levels in agricultural soils of central Chile revealed two soil clusters-one with a mean copper level of 162 mg/kg and one with a mean copper level of 751 mg/kg of soil. Samples of soils from both soil clusters were characterized on the basis of physicochemical characteristics, and copper extractability was compared by saturation and CaCl2 extraction as well as an acid-leaching procedure (TCLP). We also measured the copper content of various tissues of tomato (Lycopersicon esculentum) and onion (Allium cepa) crops growing on these soils. Other than copper levels, soils from the two clusters were quite similar, with slightly greater levels of molybdenum and cadmium in the high-copper soils. Within each cluster, extracted copper levels and total soil copper levels were not correlated. However, the three extraction procedures solubilized significantly more copper from the high-Cu soils. Mineralogical characterization of the soil particles and depth profiles of soil metal levels in a subsample of sites suggested that highly insoluble copper ore and mining wastes might account for the high copper levels. Neither total nor extractable copper levels allowed statistical prediction of the levels of copper in plant tissue. The edible tissues of both crops had the same mean copper content, regardless of the copper soil level. However, copper contents of stems and leaves were significantly higher for plants growing on the high-Cu soils. These results show that in these soils, high copper levels are associated with very insoluble copper species and thus low bioavailability of copper to crop plants.

  11. Molybdenum-copper and tungsten-copper alloys and method of making

    DOEpatents

    Schmidt, F.A.; Verhoeven, J.D.; Gibson, E.D.

    1989-05-23

    Molybdenum-copper and tungsten-copper alloys are prepared by a consumable electrode method in which the electrode consists of a copper matrix with embedded strips of refractory molybdenum or tungsten. The electrode is progressively melted at its lower end with a superatmospheric inert gas pressure maintained around the liquefying electrode. The inert gas pressure is sufficiently above the vapor pressure of copper at the liquidus temperature of the alloy being formed to suppress boiling of liquid copper. 6 figs.

  12. Molybdenum-copper and tungsten-copper alloys and method of making

    DOEpatents

    Schmidt, Frederick A.; Verhoeven, John D.; Gibson, Edwin D.

    1989-05-23

    Molybdenum-copper and tungsten-copper alloys are prepared by a consumable electrode method in which the electrode consists of a copper matrix with embedded strips of refractory molybdenum or tungsten. The electrode is progressively melted at its lower end with a superatmospheric inert gas pressure maintained around the liquifying electrode. The inert gas pressure is sufficiently above the vapor pressure of copper at the liquidus temperature of the alloy being formed to suppress boiling of liquid copper.

  13. Copper vs. Copper at the Relativistic Heavy Ion Collider (2005)

    SciTech Connect

    Brookhaven Lab - Fulvia Pilat

    2009-06-09

    To investigate a new form of matter not seen since the Big Bang, scientists are using a new experimental probe: collisions between two beams of copper ions. The use of intermediate size nuclei is expected to result in intermediate energy density - not as

  14. Copper vs. Copper at the Relativistic Heavy Ion Collider (2005)

    ScienceCinema

    Brookhaven Lab - Fulvia Pilat

    2016-07-12

    To investigate a new form of matter not seen since the Big Bang, scientists are using a new experimental probe: collisions between two beams of copper ions. The use of intermediate size nuclei is expected to result in intermediate energy density - not as

  15. Electrochemical nucleation and growth of copper and copper alloys

    NASA Astrophysics Data System (ADS)

    Shao, Wenbo

    This dissertation aims to contribute to a fundamental understanding of the physicochemical processes occurring in electrochemical nucleation and growth. To this end, the effects of various anions (chloride (Cl-), sulfate (SO42-) and sulfamate (NH2SO 3-)) on the electrochemical kinetics and the mechanism of copper reduction, as well as on the microstructure of the resulting films, were studied. On the basis of this work, the deposition of copper alloys (Cu-Ag with positive heat of mixing, Cu-Au with negative heat of mixing) was investigated with the main objective to achieve an insight on the role of solid state thermodynamics on the electrocrystallization process. Chloride ions cause two competing effects: at low chloride concentration the formation of an adsorbed chloride layer introduces an additional reaction pathway, resulting in an overall depolarization of the reduction process with no significant change of the Tafel slope. At high chloride concentration, complexation phenomena induce a cathodic polarization of the deposition process and a decrease in the Tafel slope. Chlorides cause a decrease in the density and an increased size of copper nuclei. Sulfamate depolarizes copper reduction the most and results in the largest nucleus density. Chloride promotes the faceting, and dendritic growth of copper deposits along <110> direction by introducing interfacial anisotropy. Addition of Ag in the solution or in the electrode substrate enhances copper deposition and results in an additional reduction peak. Codeposition of Cu-Ag increases nucleus density and decreases nucleus size. Such enhancement of copper deposition, the increase in nucleus density and the decrease in nucleus size by Ag could be due to the continued formation of a surface alloy of Cu-Ag and the fast interface dynamics of Ag deposition. Cu can be underpotentially codeposited in the Cu-Au alloy. Homogeneous solid solutions are grown under conditions of underpotential deposition of Cu, while

  16. Advantages and challenges of increased antimicrobial copper use and copper mining.

    PubMed

    Elguindi, Jutta; Hao, Xiuli; Lin, Yanbing; Alwathnani, Hend A; Wei, Gehong; Rensing, Christopher

    2011-07-01

    Copper is a highly utilized metal for electrical, automotive, household objects, and more recently as an effective antimicrobial surface. Copper-containing solutions applied to fruits and vegetables can prevent bacterial and fungal infections. Bacteria, such as Salmonellae and Cronobacter sakazakii, often found in food contamination, are rapidly killed on contact with copper alloys. The antimicrobial effectiveness of copper alloys in the healthcare environment against bacteria causing hospital-acquired infections such as methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli O157:H7, and Clostridium difficile has been described recently. The use of copper and copper-containing materials will continue to expand and may lead to an increase in copper mining and production. However, the copper mining and manufacturing industry and the consumer do not necessarily enjoy a favorable relationship. Open pit mining, copper mine tailings, leaching products, and deposits of toxic metals in the environment often raises concerns and sometimes public outrage. In addition, consumers may fear that copper alloys utilized as antimicrobial surfaces in food production will lead to copper toxicity in humans. Therefore, there is a need to mitigate some of the negative effects of increased copper use and copper mining. More thermo-tolerant, copper ion-resistant microorganisms could improve copper leaching and lessen copper groundwater contamination. Copper ion-resistant bacteria associated with plants might be useful in biostabilization and phytoremediation of copper-contaminated environments. In this review, recent progress in microbiological and biotechnological aspects of microorganisms in contact with copper will be presented and discussed, exploring their role in the improvement for the industries involved as well as providing better environmental outcomes.

  17. Metabolic crossroads of iron and copper

    PubMed Central

    Collins, James F; Prohaska, Joseph R; Knutson, Mitchell D

    2013-01-01

    Interactions between the essential dietary metals, iron and copper, have been known for many years. This review highlights recent advances in iron-copper interactions with a focus on tissues and cell types important for regulating whole-body iron and copper homeostasis. Cells that mediate dietary assimilation (enterocytes) and storage and distribution (hepatocytes) of iron and copper are considered, along with the principal users (erythroid cells) and recyclers of red cell iron (reticuloendothelial macrophages). Interactions between iron and copper in the brain are also discussed. Many unanswered questions regarding the role of these metals and their interactions in health and disease emerge from this synopsis, highlighting extensive future research opportunities. PMID:20384844

  18. Building a Copper Pipe "Xylophone."

    ERIC Educational Resources Information Center

    Lapp, David R.

    2003-01-01

    Explains how to use the equation for frequency of vibration of a transversely oscillating bar or pipe with both ends free to vibrate to build a simple and inexpensive xylophone from a 3-meter section of copper pipe. The instrument produces a full major scale and can be used to investigate various musical intervals. (Author/NB)

  19. PLUTONIUM-CERIUM-COPPER ALLOYS

    DOEpatents

    Coffinberry, A.S.

    1959-05-12

    A low melting point plutonium alloy useful as fuel is a homogeneous liquid metal fueled nuclear reactor is described. Vessels of tungsten or tantalum are useful to contain the alloy which consists essentially of from 10 to 30 atomic per cent copper and the balance plutonium and cerium. with the plutontum not in excess of 50 atomic per cent.

  20. COPPER CORROSION AND SOLUBILITY RESEARCH

    EPA Science Inventory

    This poster provides a very cursory summary of TTEB in-house copper research experimental systems, and extramural research projects. The field studies summarized are the Indian Hill (OH) study of the use of orthophosphate for reducing cuprosolvency in a high alkalinity water, an...

  1. Tetraphenylphosphonium copper(I) dicyanamide.

    SciTech Connect

    Schlueter, J. A.; Geiser, U.; Materials Science Division

    2007-01-01

    In the title compound, {l_brace}(C{sub 24}H{sub 20}P)[Cu(C{sub 2}N{sub 3}){sub 2}]{r_brace}{sub n}, the copper(I) dicyanamide anion forms a distorted three-dimensional single diamondoid network. Templating tetraphenylphosphonium cations reside within the cavities of the polymeric anion.

  2. Crystallization of copper metaphosphate glass

    NASA Technical Reports Server (NTRS)

    Bae, Byeong-Soo; Weinberg, Michael C.

    1993-01-01

    The effect of the valence state of copper in copper metaphosphate glass on the crystallization behavior and glass transition temperature has been investigated. The crystallization of copper metaphosphate is initiated from the surface and its main crystalline phase is copper metaphosphate (Cu(PO)3),independent of the (Cu sup 2+)/(Cu(total)). However, the crystal morphology, the relative crystallization rates, and their temperature dependences are affected by the (Cu sup 2+)/(Cu (total)) ratio in the glass. On the other hand, the totally oxidized glass crystallizes from all over the surface. The relative crystallization rate of the reduced glass to the totally oxidized glass is large at low temperature, but small at high temperature. The glass transition temperature of the glass increases as the (Cu sup 2+)/(Cu(total)) ratio is raised. It is also found that the atmosphere used during heat treatment does not influence the crystallization of the reduced glass, except for the formation of a very thin CuO surface layer when heated in air.

  3. Copper sulfate: Liquid or crystals?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two separate experiments were conducted to evaluate copper toxicity to channel catfish and free-swimming Ichthyophthirius multifiliis or Ich (the stage of Ich that can be treated); the compounds we used were CuSO4 crystals and a non-chelated liquid CuSO4 product. In 96 hr tests conducted in aquaria...

  4. CopperCore Service Integration

    ERIC Educational Resources Information Center

    Vogten, Hubert; Martens, Harrie; Nadolski, Rob; Tattersall, Colin; van Rosmalen, Peter; Koper, Rob

    2007-01-01

    In an e-learning environment there is a need to integrate various e-learning services like assessment services, collaboration services, learning design services and communication services. In this article we present the design and implementation of a generic integrative service framework, called CopperCore Service Integration (CCSI). We will…

  5. Reactivity test between beryllium and copper

    SciTech Connect

    Kawamura, H.; Kato, M.

    1995-09-01

    Beryllium has been expected for using as plasma facing material on ITER. And, copper alloy has been proposed as heat sink material behind plasma facing components. Therefore, both materials must be joined. However, the elementary process of reaction between beryllium and copper alloy does not clear in detail. For example, other authors reported that beryllium reacted with copper at high temperature, but it was not obvious about the generation of reaction products and increasing of the reaction layer. In the present work, from this point, for clarifying the elementary process of reaction between beryllium and copper, the out-of-pile compatibility tests were conducted with diffusion couples of beryllium and copper which were inserted in the capsule filled with high purity helium gas (6N). Annealing temperatures were 300, 400, 500, 600 and 700{degrees}C, and annealing periods were 100, 300 and 1000h. Beryllium specimens were hot pressed beryllium, and copper specimens were OFC (Oxygen Free Copper).

  6. Catastrophic Oxidation of Copper: A Brief Review

    NASA Astrophysics Data System (ADS)

    Belousov, V. V.; Klimashin, A. A.

    2012-10-01

    A brief review of the current understanding of copper accelerated oxidation in the presence of low-melting oxides (Bi2O3, MoO3, and V2O5) is given. Special attention is paid to the kinetics, thermodynamics, and mechanisms of accelerated oxidation of copper. The mechanisms of two stages (fast and superfast) of the copper accelerated oxidation are considered. It is shown that the fast oxidation of copper occurs by a diffusion mechanism. Oxygen diffusion along the liquid channels in the oxide scale is the rate-limiting step in the overall mechanism. The superfast oxidation of copper occurs by a fluxing mechanism. Realization of the particular mechanism depends on the mass ratio of low-melting oxide to the metal. The mass ratios of low-melting oxide to the metal and the oxygen partial pressures for superfast oxidation of copper are established. A model of the fast oxidation of copper is discussed.

  7. Chronic copper toxicity in a dairy herd

    PubMed Central

    Perrin, David J.; Schiefer, H. Bruno; Blakley, Barry R.

    1990-01-01

    The addition of excessive copper to a commercially prepared dairy ration caused chronic copper toxicity in a dairy herd. A formulation error by a feed company resulted in copper levels of 800 to 1,000 mg/kg in the “as fed concentrate,” amounting to about 400-500 mg copper/kg of the whole ration. Five animals died with typical signs of acute copper toxicity, including intravascular hemolysis and methemoglobinemia. A further 39 cows died on the farm from a combination of debilitation and secondary infectious causes, and 215 were sent to slaughter because of debilitation and poor milk production. The mortality of calves born to dams that had been fed the toxic concentrate was approximately 50%. We postulate that dairy cows, particularly pregnant cows, may be more susceptible to copper toxicity than other cattle, and suggest reexamination of the presently allowable maximum levels of copper supplementation of diets for dairy cattle. PMID:17423660

  8. Process Of Bonding Copper And Tungsten

    DOEpatents

    Slattery, Kevin T.; Driemeyer, Daniel E.

    1999-11-23

    Process for bonding a copper substrate to a tungsten substrate by providing a thin metallic adhesion promoting film bonded to a tungsten substrate and a functionally graded material (FGM) interlayer bonding the thin metallic adhesion promoting film to the copper substrate. The FGM interlayer is formed by thermal plasma spraying mixtures of copper powder and tungsten powder in a varied blending ratio such that the blending ratio of the copper powder and the tungsten powder that is fed to a plasma torch is intermittently adjusted to provide progressively higher copper content/tungsten content, by volume, ratio values in the interlayer in a lineal direction extending from the tungsten substrate towards the copper substrate. The resulting copper to tungsten joint well accommodates the difference in the coefficient of thermal expansion of the materials.

  9. Grain Refinement of Deoxidized Copper

    NASA Astrophysics Data System (ADS)

    Balart, María José; Patel, Jayesh B.; Gao, Feng; Fan, Zhongyun

    2016-10-01

    This study reports the current status of grain refinement of copper accompanied in particular by a critical appraisal of grain refinement of phosphorus-deoxidized, high residual P (DHP) copper microalloyed with 150 ppm Ag. Some deviations exist in terms of the growth restriction factor ( Q) framework, on the basis of empirical evidence reported in the literature for grain size measurements of copper with individual additions of 0.05, 0.1, and 0.5 wt pct of Mo, In, Sn, Bi, Sb, Pb, and Se, cast under a protective atmosphere of pure Ar and water quenching. The columnar-to-equiaxed transition (CET) has been observed in copper, with an individual addition of 0.4B and with combined additions of 0.4Zr-0.04P and 0.4Zr-0.04P-0.015Ag and, in a previous study, with combined additions of 0.1Ag-0.069P (in wt pct). CETs in these B- and Zr-treated casts have been ascribed to changes in the morphology and chemistry of particles, concurrently in association with free solute type and availability. No further grain-refining action was observed due to microalloying additions of B, Mg, Ca, Zr, Ti, Mn, In, Fe, and Zn (~0.1 wt pct) with respect to DHP-Cu microalloyed with Ag, and therefore are no longer relevant for the casting conditions studied. The critical microalloying element for grain size control in deoxidized copper and in particular DHP-Cu is Ag.

  10. The copper metallome in prokaryotic cells.

    PubMed

    Rensing, Christopher; McDevitt, Sylvia Franke

    2013-01-01

    As a trace element copper has an important role in cellular function like many other transition metals. Its ability to undergo redox changes [Cu(I) ↔ Cu(II)] makes copper an ideal cofactor in enzymes catalyzing electron transfers. However, this redox change makes copper dangerous for a cell since it is able to be involved in Fenton-like reactions creating reactive oxygen species (ROS). Cu(I) also is a strong soft metal and can attack and destroy iron-sulfur clusters thereby releasing iron which can in turn cause oxidative stress. Therefore, copper homeostasis has to be highly balanced to ensure proper cellular function while avoiding cell damage.Throughout evolution bacteria and archaea have developed a highly regulated balance in copper metabolism. While for many prokaryotes copper uptake seems to be unspecific, others have developed highly sophisticated uptake mechanisms to ensure the availability of sufficient amounts of copper. Within the cytoplasm copper is sequestered by various proteins and molecules, including specific copper chaperones, to prevent cellular damage. Copper-containing proteins are usually located in the cytoplasmic membrane with the catalytic domain facing the periplasm, in the periplasm of Gram-negative bacteria, or they are secreted, limiting the necessity of copper to accumulate in the cytoplasm. To prevent cellular damage due to excess copper, bacteria and archaea have developed various copper detoxification strategies. In this chapter we attempt to give an overview of the mechanisms employed by bacteria and archaea to handle copper and the importance of the metal for cellular function as well as in the global nutrient cycle.

  11. A Plasmodium falciparum copper-binding membrane protein with copper transport motifs

    PubMed Central

    2012-01-01

    Background Copper is an essential catalytic co-factor for metabolically important cellular enzymes, such as cytochrome-c oxidase. Eukaryotic cells acquire copper through a copper transport protein and distribute intracellular copper using molecular chaperones. The copper chelator, neocuproine, inhibits Plasmodium falciparum ring-to-trophozoite transition in vitro, indicating a copper requirement for malaria parasite development. How the malaria parasite acquires or secretes copper still remains to be fully elucidated. Methods PlasmoDB was searched for sequences corresponding to candidate P. falciparum copper-requiring proteins. The amino terminal domain of a putative P. falciparum copper transport protein was cloned and expressed as a maltose binding fusion protein. The copper binding ability of this protein was examined. Copper transport protein-specific anti-peptide antibodies were generated in chickens and used to establish native protein localization in P. falciparum parasites by immunofluorescence microscopy. Results Six P. falciparum copper-requiring protein orthologs and a candidate P. falciparum copper transport protein (PF14_0369), containing characteristic copper transport protein features, were identified in PlasmoDB. The recombinant amino terminal domain of the transport protein bound reduced copper in vitro and within Escherichia coli cells during recombinant expression. Immunolocalization studies tracked the copper binding protein translocating from the erythrocyte plasma membrane in early ring stage to a parasite membrane as the parasites developed to schizonts. The protein appears to be a PEXEL-negative membrane protein. Conclusion Plasmodium falciparum parasites express a native protein with copper transporter characteristics that binds copper in vitro. Localization of the protein to the erythrocyte and parasite plasma membranes could provide a mechanism for the delivery of novel anti-malarial compounds. PMID:23190769

  12. Accumulation and hyperaccumulation of copper in plants

    NASA Astrophysics Data System (ADS)

    Adam, V.; Trnkova, L.; Huska, D.; Babula, P.; Kizek, R.

    2009-04-01

    Copper is natural component of our environment. Flow of copper(II) ions in the environment depends on solubility of compounds containing this metal. Mobile ion coming from soil and rocks due to volcanic activity, rains and others are then distributed to water. Bio-availability of copper is substantially lower than its concentration in the aquatic environment. Copper present in the water reacts with other compounds and creates a complex, not available for organisms. The availability of copper varies depending on the environment, but moving around within the range from 5 to 25 % of total copper. Thus copper is stored in the sediments and the rest is transported to the seas and oceans. It is common knowledge that copper is essential element for most living organisms. For this reason this element is actively accumulated in the tissues. The total quantity of copper in soil ranges from 2 to 250 mg / kg, the average concentration is 30 mg / kg. Certain activities related to agriculture (the use of fungicides), possibly with the metallurgical industry and mining, tend to increase the total quantity of copper in the soil. This amount of copper in the soil is a problem particularly for agricultural production of food. The lack of copper causes a decrease in revenue and reduction in quality of production. In Europe, shows the low level of copper in total 18 million hectares of farmland. To remedy this adverse situation is the increasing use of copper fertilizers in agricultural soils. It is known that copper compounds are used in plant protection against various illnesses and pests. Mining of minerals is for the development of human society a key economic activity. An important site where the copper is mined in the Slovakia is nearby Smolníka. Due to long time mining in his area (more than 700 years) there are places with extremely high concentrations of various metals including copper. Besides copper, there are also detected iron, zinc and arsenic. Various plant species

  13. Copper sensitivity of Oregon coastal phytoplankton

    SciTech Connect

    Riedel, G.F.

    1983-01-01

    The copper sensitivity of natural populations of Oregon coastal phytoplankton was studied using both additions of ionic copper and Cu-TRIS free ion activity buffers in coastal seawater. Phytoplankton growth rate, taxonomic composition and copper content were examined in treatment additions. The growth rate results suggested that the deficiency of another trace metal increased the apparent toxicity of copper to phytoplankton, especially in TRIS-free ion activity buffered seawater. Laboratory experiments with isolated coastal phytoplankton species indicated that manganese deficiency exacerbated copper toxicity, and that manganese deficiency was induced in TRIS buffered seawater by a TRIS-catalyzed oxidation of Mn. When manganese additions to natural populations were employed inconjunction with ionic copper additions and TRIS-free ion regulated seawater, they showed that ambient manganese concentrations were low enough to shift the onset of copper toxicity to lower copper concentrations. The results suggest that while acute toxicity to phytoplankton by ambient concentrations of copper is unlikely, the interactions of copper and other metals, especially manganese, may influence natural coastal phytoplankton populations in more subtle ways, such as taxonomic composition.

  14. Canine Models for Copper Homeostasis Disorders

    PubMed Central

    Wu, Xiaoyan; Leegwater, Peter A. J.; Fieten, Hille

    2016-01-01

    Copper is an essential trace nutrient metal involved in a multitude of cellular processes. Hereditary defects in copper metabolism result in disorders with a severe clinical course such as Wilson disease and Menkes disease. In Wilson disease, copper accumulation leads to liver cirrhosis and neurological impairments. A lack in genotype-phenotype correlation in Wilson disease points toward the influence of environmental factors or modifying genes. In a number of Non-Wilsonian forms of copper metabolism, the underlying genetic defects remain elusive. Several pure bred dog populations are affected with copper-associated hepatitis showing similarities to human copper metabolism disorders. Gene-mapping studies in these populations offer the opportunity to discover new genes involved in copper metabolism. Furthermore, due to the relatively large body size and long life-span of dogs they are excellent models for development of new treatment strategies. One example is the recent use of canine organoids for disease modeling and gene therapy of copper storage disease. This review addresses the opportunities offered by canine genetics for discovery of genes involved in copper metabolism disorders. Further, possibilities for the use of dogs in development of new treatment modalities for copper storage disorders, including gene repair in patient-derived hepatic organoids, are highlighted. PMID:26861285

  15. Metallic copper as an antimicrobial surface.

    PubMed

    Grass, Gregor; Rensing, Christopher; Solioz, Marc

    2011-03-01

    Bacteria, yeasts, and viruses are rapidly killed on metallic copper surfaces, and the term "contact killing" has been coined for this process. While the phenomenon was already known in ancient times, it is currently receiving renewed attention. This is due to the potential use of copper as an antibacterial material in health care settings. Contact killing was observed to take place at a rate of at least 7 to 8 logs per hour, and no live microorganisms were generally recovered from copper surfaces after prolonged incubation. The antimicrobial activity of copper and copper alloys is now well established, and copper has recently been registered at the U.S. Environmental Protection Agency as the first solid antimicrobial material. In several clinical studies, copper has been evaluated for use on touch surfaces, such as door handles, bathroom fixtures, or bed rails, in attempts to curb nosocomial infections. In connection to these new applications of copper, it is important to understand the mechanism of contact killing since it may bear on central issues, such as the possibility of the emergence and spread of resistant organisms, cleaning procedures, and questions of material and object engineering. Recent work has shed light on mechanistic aspects of contact killing. These findings will be reviewed here and juxtaposed with the toxicity mechanisms of ionic copper. The merit of copper as a hygienic material in hospitals and related settings will also be discussed.

  16. Canine Models for Copper Homeostasis Disorders.

    PubMed

    Wu, Xiaoyan; Leegwater, Peter A J; Fieten, Hille

    2016-02-04

    Copper is an essential trace nutrient metal involved in a multitude of cellular processes. Hereditary defects in copper metabolism result in disorders with a severe clinical course such as Wilson disease and Menkes disease. In Wilson disease, copper accumulation leads to liver cirrhosis and neurological impairments. A lack in genotype-phenotype correlation in Wilson disease points toward the influence of environmental factors or modifying genes. In a number of Non-Wilsonian forms of copper metabolism, the underlying genetic defects remain elusive. Several pure bred dog populations are affected with copper-associated hepatitis showing similarities to human copper metabolism disorders. Gene-mapping studies in these populations offer the opportunity to discover new genes involved in copper metabolism. Furthermore, due to the relatively large body size and long life-span of dogs they are excellent models for development of new treatment strategies. One example is the recent use of canine organoids for disease modeling and gene therapy of copper storage disease. This review addresses the opportunities offered by canine genetics for discovery of genes involved in copper metabolism disorders. Further, possibilities for the use of dogs in development of new treatment modalities for copper storage disorders, including gene repair in patient-derived hepatic organoids, are highlighted.

  17. Nanoscale Copper and Copper Compounds for Advanced Device Applications

    NASA Astrophysics Data System (ADS)

    Chen, Lih-Juann

    2016-12-01

    Copper has been in use for at least 10,000 years. Copper alloys, such as bronze and brass, have played important roles in advancing civilization in human history. Bronze artifacts date at least 6500 years. On the other hand, discovery of intriguing properties and new applications in contemporary technology for copper and its compounds, particularly on nanoscale, have continued. In this paper, examples for the applications of Cu and Cu alloys for advanced device applications will be given on Cu metallization in microelectronics devices, Cu nanobats as field emitters, Cu2S nanowire array as high-rate capability and high-capacity cathodes for lithium-ion batteries, Cu-Te nanostructures for field-effect transistor, Cu3Si nanowires as high-performance field emitters and efficient anti-reflective layers, single-crystal Cu(In,Ga)Se2 nanotip arrays for high-efficiency solar cell, multilevel Cu2S resistive memory, superlattice Cu2S-Ag2S heterojunction diodes, and facet-dependent Cu2O diode.

  18. Copper toxicity and copper-zinc interactions in amphibian embryos.

    PubMed

    Herkovits, J; Helguero, L A

    1998-09-29

    The copper hazard was evaluated by means of a 7-day toxicity test with Bufo arenarum embryos. The LC50 and LC10 values from 24 to 168 h of exposure were approx. 0.085 and 0.05 mg Cu2+/1, respectively, while the LC90 resulted in 0.155 mg Cu2+/1 but in this case from 96 h onwards the LC90 diminished up to approx. 0.105 mg Cu2+/1. These data plotted as Toxicity Profiles (TOP) provide a better understanding of concentration and time-dependent thresholds. For instance, exposure threshold occurs within the first 24 h of treatment while for concentration thresholds LC10 and LC90 seem to be more meaningful than LC50 because the S.D. of this last value is overlapping those of LC10 and LC90 for most of the exposure period evaluated. Toxicity data corresponds to a pH of 6.8 which is normal for the maintaining media. Combined treatments of copper and zinc point out a beneficial effect of zinc proportional to the zinc concentration in the maintaining media, e.g. 100% of protection was achieved with 30 mg Zn2+/1 for a copper concentration exerting 90% of mortality. The presence of Cu2+ did not enhance Zn2+ toxicity. The results are discussed in terms of water quality criteria for wildlife and human health protection purposes.

  19. Investigations of copper speciation and bioavailability

    SciTech Connect

    Deaver, E.; Rodgers, J.H. Jr.

    1995-12-31

    Speciation, or form in which copper occurs, can effect the bioavailability and therefore, the toxicity of that element. One needs to determine the bioavailable forms of copper in sediment/water effects on organisms. In both water and sediment experiments, physical/chemical factors influencing copper speciation were evaluated and related to organism responses. Ten day aqueous experiments encompassing a range of pH (6.5--8.1), alkalinity (10--70 mg/L as CaCO{sub 3}), hardness (10--70 mg/L as CaCO{sub 3}) and conductivity (30--300 umhos/cm) were conducted using Hyalella azteca. Amphipod survival was evaluated relative to changes in water characteristics and concomitant changes in copper speciation as measured using atomic adsorption spectroscopy (AA) for acid extractable copper, and differential pulse anodic stripping voltammetry (DPASV) for labile copper. Ten day LC50s based on AA measured copper concentrations ranged from 42 to 142 ug/L Cu, and LC50s based on DPASV measured copper concentrations ranged from 17.4--24.8 ug/L Cu. Ten day sediment experiments encompassing a range of sediment pH, organic carbon content, acid volatile sulfides and redox concentrations were also conducted using H. azteca. Overlying water (AA and DPASV) and sediment copper concentrations (AA) were measured and evaluated relative to organism survival. Ten day sediment test LC50s based on DPASV measured copper concentrations in overlying water were 18.5 and 18 ug/L Cu for experiments in sandy and silty sediments, respectively. Organism survival, used as a measure of bioavailable copper, was evaluated in relation to measured copper species concentrations and used to develop guidelines for predicting copper toxicity in freshwater systems.

  20. Copper-induced production of copper-binding supernatant proteins by the marine bacterium Vibrio alginolyticus

    SciTech Connect

    Harwood-Sears, V.; Gordon, A.S. )

    1990-05-01

    Growth of the marine bacterium Vibrio alginolyticus is temporarily inhibited by micromolar levels of copper. During the copper-induced lag phase, supernatant compounds and detoxify copper are produced. In this study two copper-inducible supernatant proteins having molecular masses of ca. 21 and 19 kilodaltons (CuBP1 and CuPB2) were identified; these proteins were, respectively, 25 and 46 times amplified in supernatants of copper-challenged cultures compared with controls. Experiments in which chloramphenicol was added to cultures indicated that there was de novo synthesis of these proteins in response to copper. When supernatants were separated by gel permeation chromatography, CuBP1 and CuPB2 coeluted with a copper-induced peak in copper-binding activity. CuBP1 and CuBP2 from whole supernatants were concentrated and partially purified by using a copper-charged immobilized metal ion affinity chromatography column, confirming the affinity of these proteins for copper. A comparison of cell pellets and supernatants demonstrated that CuBP1 was more concentrated in supernatants than in cells. Our data are consistent with a model for a novel mechanism of copper detoxification in which excretion of copper-binding protein is induced by copper.

  1. Biosorption and bioreduction of copper from different copper compounds in aqueous solution.

    PubMed

    Andreazza, Robson; Okeke, Benedict C; Pieniz, Simone; Bento, Fátima M; Camargo, Flávio A O

    2013-06-01

    High copper concentration is toxic for living organisms including humans. Biosorption is a bioremediation technique that can remove copper and other pollutants from aqueous medium and soils, consequently cleaning the environment. The aim of this study was, therefore, to investigate the influence of different copper compounds (Cu(II) as CuCl2; Cu(II) as CuSO4; and Cu(I) as CuCl) on copper bioreduction and biosorption using four copper-resistant bacteria isolated from the rhizosphere of two plants (Avena sativa and Plantago lanceolata) in aqueous matrix. Copper resistance profile, bioreduction, and biosorption after 48 h of incubation were evaluated. The isolates displayed high copper resistance. However, isolate A1 did not grow very well in the CuCl2 and isolate T5 was less resistant to copper in aqueous solutions amended with CuCl (Cu(I)). The best copper source for copper bioreduction and biosorption was CuSO4 and the isolates removed as much as ten times more copper than in aqueous solutions amended with the other copper compounds. Moreover, Cu(I) did not succumb to biosorption, although the microbes were resistant to aqueous solutions of CuCl. In summary, Cu(II) from CuSO4 was furthermost susceptible to bioreduction and biosorption for all isolates. This is an indication that copper contamination of the environment from the use of CuSO4 as an agrochemical is amenable to bioremediation.

  2. Evaluation of copper resistant bacteria from vineyard soils and mining waste for copper biosorption.

    PubMed

    Andreazza, R; Pieniz, S; Okeke, B C; Camargo, F A O

    2011-01-01

    Vineyard soils are frequently polluted with high concentrations of copper due application of copper sulfate in order to control fungal diseases. Bioremediation is an efficient process for the treatment of contaminated sites. Efficient copper sorption bacteria can be used for bioremoval of copper from contaminated sites. In this study, a total of 106 copper resistant bacteria were examined for resistance to copper toxicity and biosorption of copper. Eighty isolates (45 from vineyard Mollisol, 35 from Inceptisol) were obtained from EMBRAPA (Empresa Brasileira de Pesquisa Agropecuária) experimental station, Bento Gonçalves, RS, Brazil (29°09'53.92″S and 51°31'39.40″W) and 26 were obtained from copper mining waste from Caçapava do Sul, RS, Brazil (30°29'43.48″S and 53'32'37.87W). Based on resistance to copper toxicity and biosorption, 15 isolates were identified by 16S rRNA gene sequencing. Maximal copper resistance and biosorption at high copper concentration were observed with isolate N2 which removed 80 mg L(-1) in 24 h. Contrarily isolate N11 (Bacillus pumilus) displayed the highest specific copper biosorption (121.82 mg/L/OD unit in 24 h). GenBank MEGABLAST analysis revealed that isolate N2 is 99% similar to Staphylococcus pasteuri. Results indicate that several of our isolates have potential use for bioremediation treatment of vineyards soils and mining waste contaminated with high copper concentration.

  3. Plasmid-encoded copper resistance and precipitation by Mycobacterium scrofulaceum.

    PubMed Central

    Erardi, F X; Failla, M L; Falkinham, J O

    1987-01-01

    A copper-tolerant Mycobacterium scrofulaceum strain was able to remove copper from culture medium by sulfate-dependent precipitation as copper sulfide. Such precipitation of copper sulfide was not observed in a derivative that lacks a 173-kilobase plasmid. In addition, the plasmid-carrying strain has a sulfate-independent copper resistance mechanism. PMID:3662522

  4. Copper as a target for prostate cancer therapeutics: copper-ionophore pharmacology and altering systemic copper distribution

    PubMed Central

    Denoyer, Delphine; Pearson, Helen B.; Clatworthy, Sharnel A.S.; Smith, Zoe M.; Francis, Paul S.; Llanos, Roxana M.; Volitakis, Irene; Phillips, Wayne A.; Meggyesy, Peter M.; Masaldan, Shashank; Cater, Michael A.

    2016-01-01

    Copper-ionophores that elevate intracellular bioavailable copper display significant therapeutic utility against prostate cancer cells in vitro and in TRAMP (Transgenic Adenocarcinoma of Mouse Prostate) mice. However, the pharmacological basis for their anticancer activity remains unclear, despite impending clinical trails. Herein we show that intracellular copper levels in prostate cancer, evaluated in vitro and across disease progression in TRAMP mice, were not correlative with copper-ionophore activity and mirrored the normal levels observed in patient prostatectomy tissues (Gleason Score 7 & 9). TRAMP adenocarcinoma cells harbored markedly elevated oxidative stress and diminished glutathione (GSH)-mediated antioxidant capacity, which together conferred selective sensitivity to prooxidant ionophoric copper. Copper-ionophore treatments [CuII(gtsm), disulfiram & clioquinol] generated toxic levels of reactive oxygen species (ROS) in TRAMP adenocarcinoma cells, but not in normal mouse prostate epithelial cells (PrECs). Our results provide a basis for the pharmacological activity of copper-ionophores and suggest they are amendable for treatment of patients with prostate cancer. Additionally, recent in vitro and mouse xenograft studies have suggested an increased copper requirement by prostate cancer cells. We demonstrated that prostate adenocarcinoma development in TRAMP mice requires a functional supply of copper and is significantly impeded by altered systemic copper distribution. The presence of a mutant copper-transporting Atp7b protein (tx mutation: A4066G/Met1356Val) in TRAMP mice changed copper-integration into serum and caused a remarkable reduction in prostate cancer burden (64% reduction) and disease severity (grade), abrogating adenocarcinoma development. Implications for current clinical trials are discussed. PMID:27175597

  5. Thermoelectric Study of Copper Selenide

    NASA Astrophysics Data System (ADS)

    Yao, Mengliang; Liu, Weishu; Ren, Zhifeng; Opeil, Cyril

    2014-03-01

    Nanostructuring has been shown to be an effective approach in reducing lattice thermal conductivity and improving the figure of merit of thermoelectric materials. Copper selenide is a layered structure material, which has a low thermal conductivity and p-type Seebeck coefficient at low temperatures. We have evaluated several hot-pressed, nanostructured copper selenide samples with different dopants for their thermoelectric properties. The phenomenon of the charge-density wave observed in the nanocomposite, resistivity, Seebeck, thermal conductivity and carrier mobility will be discussed. Funding for this research was provided by the Solid State Solar - Thermal Energy Conversion Center (S3TEC), an Energy Frontier Research Center sponsored by the DOE, Office of Basic Energy Science, Award No. DE-SC0001299/ DE-FG02-09ER46577.

  6. Copper-philic carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Belgamwar, Sachin U.; Sharma, Niti Nipun

    2016-04-01

    Carbon nanotube is having poor wet-ability with copper metal. Wet-ability of carbon nanotube was improved by exposing and creating more active sites on the surface of carbon nanotube. Carbon nanotubes were subjected to the prolong ultrasonication treatment of 20×103 Hz and 500W, which helped in disentanglement of carbon nanotube agglomerates and in breaking the weak bonds like pentagonal or heptagonal structure on the surface and on the CNT cap. Disentanglement of the carbon nanotube, resulted in exposing the defective sites on the surface and breaking of weak bonds, which assisted in creating the new defects on the surface. This process results in generates more active sites on the surface and it helps in improving the wet-ability of the carbon nanotube in copper.

  7. Durable Copper Polyimide Adhesive Bonds

    DTIC Science & Technology

    1983-05-24

    the outer surface is primarily cupric oxide, and that there is a gradient through the thickness that becomes progressively richer in cuprous oxide...Further, they state that cuprous is an unstable forr and may be oxidized to cupric oxide during high- temperature pressing by reacting with residual...least forty years ago by Campbell and Thomas, when they showed that copper almost instantaneously developed a "tarnish" of cuprous oxide(5). The test

  8. Explosive compact-coating of tungsten–copper alloy to a copper surface

    NASA Astrophysics Data System (ADS)

    Chen, Xiang; Li, Xiaojie; Yan, Honghao; Wang, Xiaohong; Miao, Yusong

    2017-03-01

    This study proposed a new method for coating tungsten–copper alloy to copper surface. First, the tungsten–copper alloy powder was pre-compacted to the copper surface. Then, the powder in the hydrogen atmosphere was sintered, and the pre-compacted powder was compacted by explosive compact-coating. Finally, diffusion sintering was conducted to improve the density of the coating layer. The theoretical density of the coating reached 99.3%. Microstructure characteristics indicated that tungsten and copper powders were well mixed. Tungsten particles were larger than copper particles. Scanning electron microscope (SEM) fracture surface analysis was different from the traditional fracture of metals. Coating and substrate joint surfaces, which were analyzed by SEM, indicated that the tungsten–copper alloy was sintered on the copper surface. The hardness of the coating layer was 197.6–245.2 HV, and the hardness of the substrate was approximately 55 HV.

  9. Reduction reaction analysis of nanoparticle copper oxide for copper direct bonding using formic acid

    NASA Astrophysics Data System (ADS)

    Fujino, Masahisa; Akaike, Masatake; Matsuoka, Naoya; Suga, Tadatomo

    2017-04-01

    Copper direct bonding is required for electronics devices, especially power devices, and copper direct bonding using formic acid is expected to lower the bonding temperature. In this research, we analyzed the reduction reaction of copper oxide using formic acid with a Pt catalyst by electron spin resonance analysis and thermal gravimetry analysis. It was found that formic acid was decomposed and radicals were generated under 200 °C. The amount of radicals generated was increased by adding the Pt catalyst. Because of these radicals, both copper(I) oxide and copper(II) oxide start to be decomposed below 200 °C, and the reduction of copper oxide is accelerated by reactants such as H2 and CO from the decomposition of formic acid above 200 °C. The Pt catalyst also accelerates the reaction of copper oxide reduction. Herewith, it is considered that the copper surface can be controlled more precisely by using formic acid to induce direct bonding.

  10. Copper hepatotoxicity attenuated by zinc

    SciTech Connect

    Schilsky, M.; Blank, R.; Stockert, R.; Sternlieb, I.; Scheinberg, I.H.

    1987-05-01

    The manifestations of hepatocellular copper toxicity and the role of zinc in its prevention have been investigated. When incubated for 48 hrs in media to which increasing concentrations of Cu acetate are added, HepG2 cells exhibit reduced viability with an LD/sub 50/ of 750 uM. Morphology, cell membranes and mitochondria appeared to be normal after 1 hr exposure to 1000 uM Cu acetate, but progressive abnormalities were noted between 3 and 12 hrs. In the first hour of exposure to this concentration of copper, protein synthesis (/sup 35/S-methionine uptake into TCA precipitates) was reduced to 20% of control while transcription (/sup 3/H-uridine incorporation) increased to 139% of controls. Preincubation with 200 uM Zn acetate for 2 hr increased cellular survival and allowed protein synthesis to proceed at 80% of control levels during exposure to 1000 uM Cu acetate. /sup 67/Cu uptake was unaltered by incubation with up to 500 uM Zn acetate. SDS-PAGE of cellular proteins after treatment with 200 uM Zn produced a different banding pattern suggesting induction of specific proteins. Since the addition of 1000 uM Cu acetate to a wheat-germ-translation-system using B-globin mRNA reduced translation by 95%, they conclude from this and the foregoing data that copper inhibits protein synthesis at the level of translation and that zinc mitigates this inhibition in hepatocytes.

  11. Copper: a metal for the ages

    USGS Publications Warehouse

    Doebrich, Jeff

    2009-01-01

    Copper was one of the first metals ever extracted and used by humans, and it has made vital contributions to sustaining and improving society since the dawn of civilization. Copper was first used in coins and ornaments starting about 8000 B.C., and at about 5500 B.C., copper tools helped civilization emerge from the Stone Age. The discovery that copper alloyed with tin produces bronze marked the beginning of the Bronze Age at about 3000 B.C. Copper is easily stretched, molded, and shaped; is resistant to corrosion; and conducts heat and electricity efficiently. As a result, copper was important to early humans and continues to be a material of choice for a variety of domestic, industrial, and high-technology applications today.

  12. Risks and benefits of copper in light of new insights of copper homeostasis.

    PubMed

    de Romaña, Daniel López; Olivares, Manuel; Uauy, Ricardo; Araya, Magdalena

    2011-01-01

    Copper is an essential micronutrient involved in a variety of biological processes indispensable to sustain life. At the same time, it can be toxic when present in excess, the most noticeable chronic effect being liver damage. Potent, efficient regulatory mechanisms control copper absorption in the digestive tract and copper biliary excretion; absorption ranges between 12 and 60% in humans, depending on Cu intake, presence of other factors in the diet that may promote or inhibit its absorption and on the copper status of the individual. Current evidence suggests that copper deficiency may be more prevalent than previously thought, while copper toxicity is uncommon under customary daily life conditions. Menkes syndrome and Wilson disease are genetic conditions associated with severe copper deficiency and severe copper toxicity, respectively. Effects of milder degrees of copper deficiency and excess copper exposure are not well described, mainly due to lack of sensitive and specific indicators; serum copper concentration and ceruloplasmin are the most frequently used indicators, but they only detect rather intense changes of copper status. Of the many proteins assessed as potential markers of copper status the chaperone of Zn-Cu superoxide dismutase (CCS1) has yielded promising results; data on its performance under different conditions are needed to confirm its use as an indicator of early copper deficiency. Defining copper requirements and upper safe limits of consumption (UL) is a complex process since there are adverse health consequences from both copper deficiency and copper excess (U shape curve). The regulatory framework for risk assessment of essential trace elements introduced by the International Programme on Chemical Safety (IPCS) has proposed a homeostatic model to determine the Adequate Range of Oral Intake (AROI) of essential trace elements; the nadir of the resulting U shape curve serves to define the AROI. At this range of intake physiological

  13. Effects of dietary supplementation with copper sulfate or tribasic copper chloride on broiler performance, relative copper bioavailability, and oxidation stability of vitamin E in feed.

    PubMed

    Luo, X G; Ji, F; Lin, Y X; Steward, F A; Lu, L; Liu, B; Yu, S X

    2005-06-01

    An experiment was conducted using a total of 420, 1-d-old, Arbor Acres commercial male chicks to compare copper sulfate and tribasic copper chloride (TBCC) as sources of supplemental copper for broilers. Chicks were randomly allotted to 1 of 7 treatments for 6 replicates of 10 birds each and were fed a basal corn-soybean meal diet (11.45 mg/kg copper) supplemented with 0, 150, 300, or 450 mg/kg copper from copper sulfate or TBCC for 21 d. Chicks fed 450 mg/kg copper as copper sulfate had lower (P < 0.01) average daily feed intake and average daily gain than those consuming other diets. Feeding supplemental copper increased linearly (P < 0.0001) liver copper concentrations regardless of copper source. The slopes of regressions of log10 liver copper on different independent variables used in regressions differ (P < 0.05) between the 2 copper sources. Linear regression over nonzero dietary levels of log10 transformed liver copper concentration on added copper intake resulted in a slope ratio estimate of 109.0 +/- 3.4% (with a 95% confidence interval from 102.2 to 115.8) for bioavailability of copper from TBCC compared with 100 for that in copper sulfate. When the feeds were stored at room temperature for 10 or 21 d, the vitamin E content in the feed fortified with 300 mg/kg copper as TBCC was higher (P < 0.01) than that in the feed added with 300 mg/kg copper as CuSO4. The vitamin E contents in liver and plasma of broilers given TBCC were also higher (P < 0.01) than those of birds fed copper sulfate. The results from this study indicate that TBCC is a safer product and more available to broilers than copper sulfate, and it is chemically less active than copper sulfate in promoting the oxidation of vitamin E in feed.

  14. CNC Machining Of The Complex Copper Electrodes

    NASA Astrophysics Data System (ADS)

    Popan, Ioan Alexandru; Balc, Nicolae; Popan, Alina

    2015-07-01

    This paper presents the machining process of the complex copper electrodes. Machining of the complex shapes in copper is difficult because this material is soft and sticky. This research presents the main steps for processing those copper electrodes at a high dimensional accuracy and a good surface quality. Special tooling solutions are required for this machining process and optimal process parameters have been found for the accurate CNC equipment, using smart CAD/CAM software.

  15. Copper chloride cathode for a secondary battery

    NASA Astrophysics Data System (ADS)

    Bugga, Ratnakumar V.; Distefano, Salvador; Nagasubramanian, Ganesan; Bankston, Clyde P.

    1990-07-01

    Higher energy and power densities are achieved in a secondary battery based on molten sodium and a solid, ceramic separator such as a beta alumina and a molten catholyte such as sodium tetrachloroaluminate and a copper chloride cathode. The higher cell voltage of copper chloride provides higher energy densities and the higher power density results from increased conductivity resulting from formation of copper as discharge proceeds.

  16. Electrochemical synthesis of highly crystalline copper nanowires

    SciTech Connect

    Kaur, Amandeep; Gupta, Tanish; Kumar, Akshay; Kumar, Sanjeev; Singh, Karamjeet; Thakur, Anup

    2015-05-15

    Copper nanowires were fabricated within the pores of anodic alumina template (AAT) by template synthesis method at pH = 2.9. X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were used to investigate the structure, morphology and composition of fabricated nanowires. These characterizations revealed that the deposited copper nanowires were highly crystalline in nature, dense and uniform. The crystalline copper nanowires are promising in application of future nanoelectronic devices and circuits.

  17. Copper chloride cathode for a secondary battery

    NASA Technical Reports Server (NTRS)

    Bugga, Ratnakumar V. (Inventor); Distefano, Salvador (Inventor); Nagasubramanian, Ganesan (Inventor); Bankston, Clyde P. (Inventor)

    1990-01-01

    Higher energy and power densities are achieved in a secondary battery based on molten sodium and a solid, ceramic separator such as a beta alumina and a molten catholyte such as sodium tetrachloroaluminate and a copper chloride cathode. The higher cell voltage of copper chloride provides higher energy densities and the higher power density results from increased conductivity resulting from formation of copper as discharge proceeds.

  18. Radioactivity at the Copper Creek copper lode prospect, Eagle district, east-central Alaska

    USGS Publications Warehouse

    Wedow, Helmuth; Tolbert, Gene Edward

    1952-01-01

    Investigation of radioactivity anomalies at the Copper Creek copper lode prospect, Eagle district, east-central Alaska, during 1949 disclosed that the radioactivity is associated with copper mineralization in highly metamorphosed sedimentary rocks. These rocks are a roof pendant in the Mesozoic "Charley River" batholith. The radioactivity is probably all due to uranium associated with bornite and malachite.

  19. High intensity copper atom beam - Preliminary results

    NASA Technical Reports Server (NTRS)

    Kelly, A. J.; Santavicca, D.

    1973-01-01

    The development of a nozzle which gas-dynamically accelerates neutral copper atoms at controlled energy levels and flux rates suitable for the investigation of inelastic copper atom collision processes is reported. Preliminary test data demonstrate that vapor-deposited rhenium nozzles do not degrade in the presence of copper vapor at high temperatures. Operation with high purity helium gas at nozzle stagnation temperatures in the range 2650-2700 K and total stagnation pressures from 1/4 to 2 atm with continuous copper atom flux rates of approximately 10 to the 18th power per second has been maintained, for a total time of 8-1/2 h to date.

  20. The role of copper in neurodegenerative disease.

    PubMed

    Waggoner, D J; Bartnikas, T B; Gitlin, J D

    1999-08-01

    Copper is an essential trace metal which plays a fundamental role in the biochemistry of the human nervous system. Menkes disease and Wilson disease are inherited disorders of copper metabolism and the dramatic neurodegenerative phenotypes of these two diseases underscore the essential nature of copper in nervous system development as well as the toxicity of this metal when neuronal copper homeostasis is perturbed. Ceruloplasmin contains 95% of the copper found in human plasma and inherited loss of this essential ferroxidase is associated with progressive neurodegeneration of the retina and basal ganglia. Gain-of-function mutations in the cytosolic copper enzyme superoxide dismutase result in the motor neuron degeneration of amyotrophic lateral sclerosis and current evidence suggests a direct pathogenic role for copper in this process. Recent studies have also implicated copper in the pathogenesis of neuronal injury in Alzheimer's disease and the prion-mediated encephalopathies, suggesting that further elucidation of the mechanisms of copper trafficking and metabolism within the nervous system will be of direct relevance to our understanding of the pathophysiology and treatment of neurodegenerative disease.

  1. [Copper in methane oxidation: a review].

    PubMed

    Su, Yao; Kong, Jiao-Yan; Zhang, Xuan; Xia, Fang-Fang; He, Ruo

    2014-04-01

    Methane bio-oxidation plays an important role in the global methane balance and warming mitigation, while copper has a crucial function in methane bio-oxidation. On one side, copper is known to be a key factor in regulating the expression of the genes encoding the two forms of methane monooxygenases (MMOs) and is the essential metal element of the particulate methane monooxygenase (pMMO). On the other side, the content and fractionation of copper in the environment have great effects on the distribution of methanotrophs and their metabolic capability of methane and non-methane organic compounds, as well as on the copper-specific uptake systems in methanotrophs. Thus, it is meaningful to know the role of copper in methane bio-oxidation for comprehensive understanding of this process and is valuable for guiding the application of methanotrophs in greenhouse gas removal and pollution remediation. In this paper, the roles of copper in methane oxidation were reviewed, including the effect of copper on methanotrophic community structure and activity, the expression and activity of MMOs as well as the copper uptake systems in methanotrophs. The future studies of copper and methane oxidation were also discussed.

  2. Unraveling the Amycolatopsis tucumanensis copper-resistome.

    PubMed

    Dávila Costa, José Sebastián; Kothe, Erika; Abate, Carlos Mauricio; Amoroso, María Julia

    2012-10-01

    Heavy metal pollution is widespread causing serious ecological problems in many parts of the world; especially in developing countries where a budget for remediation technology is not affordable. Therefore, screening for microbes with high accumulation capacities and studying their stable resistance characteristics is advisable to define cost-effective any remediation strategies. Herein, the copper-resistome of the novel copper-resistant strain Amycolatopsis tucumanensis was studied using several approaches. Two dimensional gel electrophoresis revealed that proteins of the central metabolism, energy production, transcriptional regulators, two-component system, antioxidants and protective metabolites increased their abundance upon copper-stress conditions. Transcriptome analysis revealed that in presence of copper, superoxide dismutase, alkyl hydroperoxide reductase and mycothiol reductase genes were markedly induced in expression. The oxidative damage of protein and lipid from A. tucumanensis was negligible compared with that observed in the copper-sensitive strain Amycolatopsis eurytherma. Thus, we provide evidence that A. tucumamensis shows a high adaptation towards copper, the sum of which is proposed as the copper-resistome. This adaptation allows the strain to accumulate copper and survive this stress; besides, it constitutes the first report in which the copper-resistome of a strain of the genus Amycolatopsis with bioremediation potential has been evaluated.

  3. Material flows generated by pyromet copper smelting

    USGS Publications Warehouse

    Goonan, T.G.

    2005-01-01

    Copper production through smelting generates large volumes of material flows. As copper contained in ore becomes copper contained in concentrate to be fed into the smelting process, it leaves behind an altered landscape, sometimes mine waste, and always mill tailings. Copper concentrate, fluxing materials, fuels, oxygen, recyclables, scrap and water are inputs to the process. Dust (recycled), gases - containing carbon dioxide (CO2) (dissipated) and sulfur dioxide (SO2) (mostly collected, transformed and sold) and slag (discarded or sold) - are among the significant process outputs. This article reports estimates of the flows of these input/output materials for a particular set of smelters studied in some countries.

  4. Release of Micronized Copper Particles from Pressure Treated Wood Products.

    EPA Science Inventory

    Micronized copper pressure treated lumber (PTL) has recently been introduced to the consumer market as a replacement for ionized copper PTL. The presence of particulate rather than aqueous copper raises concerns about possible human or environmental exposure. Two common pathways ...

  5. Neutron-activation analysis applied to copper ores and artifacts

    NASA Technical Reports Server (NTRS)

    Linder, N. F.

    1970-01-01

    Neutron activation analysis is used for quantitative identification of trace metals in copper. Establishing a unique fingerprint of impurities in Michigan copper would enable identification of artifacts made from this copper.

  6. Surface structure influences contact killing of bacteria by copper

    PubMed Central

    Zeiger, Marco; Solioz, Marc; Edongué, Hervais; Arzt, Eduard; Schneider, Andreas S

    2014-01-01

    Copper kills bacteria rapidly by a mechanism that is not yet fully resolved. The antibacterial property of copper has raised interest in its use in hospitals, in place of plastic or stainless steel. On the latter surfaces, bacteria can survive for days or even weeks. Copper surfaces could thus provide a powerful accessory measure to curb nosocomial infections. We here investigated the effect of the copper surface structure on the efficiency of contact killing of Escherichia coli, an aspect which so far has received very little attention. It was shown that electroplated copper surfaces killed bacteria more rapidly than either polished copper or native rolled copper. The release of ionic copper was also more rapid from electroplated copper compared to the other materials. Scanning electron microscopy revealed that the bacteria nudged into the grooves between the copper grains of deposited copper. The findings suggest that, in terms of contact killing, more efficient copper surfaces can be engineered. PMID:24740976

  7. Surface structure influences contact killing of bacteria by copper.

    PubMed

    Zeiger, Marco; Solioz, Marc; Edongué, Hervais; Arzt, Eduard; Schneider, Andreas S

    2014-06-01

    Copper kills bacteria rapidly by a mechanism that is not yet fully resolved. The antibacterial property of copper has raised interest in its use in hospitals, in place of plastic or stainless steel. On the latter surfaces, bacteria can survive for days or even weeks. Copper surfaces could thus provide a powerful accessory measure to curb nosocomial infections. We here investigated the effect of the copper surface structure on the efficiency of contact killing of Escherichia coli, an aspect which so far has received very little attention. It was shown that electroplated copper surfaces killed bacteria more rapidly than either polished copper or native rolled copper. The release of ionic copper was also more rapid from electroplated copper compared to the other materials. Scanning electron microscopy revealed that the bacteria nudged into the grooves between the copper grains of deposited copper. The findings suggest that, in terms of contact killing, more efficient copper surfaces can be engineered.

  8. Evaluations of bioavailable copper in amended wetland sediments

    SciTech Connect

    Deaver, E.; Rodgers, J.H. Jr.

    1994-12-31

    Copper sulfate was added to the water column of six of twelve wetland mesocosms. In successive 10d experiments using invertebrates Hyalella azteca and Chironomus tentans, sediment toxicity and copper bioavailability were examined in sediments collected monthly from wetlands amended with copper sulfate, untreated wetlands, and control sediments. Evaluations included examinations of temporal changes in toxicity, bioavailability of aqueous and sediment associated copper, and comparison of organism responses to copper. In some cases copper remained acutely toxic over the 6 month study period, however, total copper concentrations in sediment had no relation to bioavailable copper. The relationship of copper speciation to bioavailability was discerned by measuring total copper (AA), labile copper (ASV) and copper ion activity (ISE) during these sediment toxicity experiments.

  9. 40 CFR 415.360 - Applicability; description of the copper salts production subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... copper salts production subcategory. 415.360 Section 415.360 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Copper Salts Production Subcategory § 415.360 Applicability; description of the copper... copper salts, including (a) copper sulfate, copper chloride, copper iodide, and copper nitrate, and...

  10. 40 CFR 415.360 - Applicability; description of the copper salts production subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... copper salts production subcategory. 415.360 Section 415.360 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Copper Salts Production Subcategory § 415.360 Applicability; description of the copper... copper salts, including (a) copper sulfate, copper chloride, copper iodide, and copper nitrate, and...

  11. 40 CFR 415.360 - Applicability; description of the copper salts production subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... copper salts production subcategory. 415.360 Section 415.360 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Copper Salts Production Subcategory § 415.360 Applicability; description of the copper... copper salts, including (a) copper sulfate, copper chloride, copper iodide, and copper nitrate, and...

  12. 40 CFR 415.360 - Applicability; description of the copper salts production subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... copper salts production subcategory. 415.360 Section 415.360 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Copper Salts Production Subcategory § 415.360 Applicability; description of the copper... copper salts, including (a) copper sulfate, copper chloride, copper iodide, and copper nitrate, and...

  13. Copper Nanoparticles in Click Chemistry.

    PubMed

    Alonso, Francisco; Moglie, Yanina; Radivoy, Gabriel

    2015-09-15

    The challenges of the 21st century demand scientific and technological achievements that must be developed under sustainable and environmentally benign practices. In this vein, click chemistry and green chemistry walk hand in hand on a pathway of rigorous principles that help to safeguard the health of our planet against negligent and uncontrolled production. Copper-catalyzed azide-alkyne cycloaddition (CuAAC), the paradigm of a click reaction, is one of the most reliable and widespread synthetic transformations in organic chemistry, with multidisciplinary applications. Nanocatalysis is a green chemistry tool that can increase the inherent effectiveness of CuAAC because of the enhanced catalytic activity of nanostructured metals and their plausible reutilization capability as heterogeneous catalysts. This Account describes our contribution to click chemistry using unsupported and supported copper nanoparticles (CuNPs) as catalysts prepared by chemical reduction. Cu(0)NPs (3.0 ± 1.5 nm) in tetrahydrofuran were found to catalyze the reaction of terminal alkynes and organic azides in the presence of triethylamine at rates comparable to those achieved under microwave heating (10-30 min in most cases). Unfortunately, the CuNPs underwent dissolution under the reaction conditions and consequently could not be recovered. Compelling experimental evidence on the in situ generation of highly reactive copper(I) chloride and the participation of copper(I) acetylides was provided. The supported CuNPs were found to be more robust and efficient catalyst than the unsupported counterpart in the following terms: (a) the multicomponent variant of CuAAC could be applied; (b) the metal loading could be substantially decreased; (c) reactions could be conducted in neat water; and (d) the catalyst could be recovered easily and reutilized. In particular, the catalyst composed of oxidized CuNPs (Cu2O/CuO, 6.0 ± 2.0 nm) supported on carbon (CuNPs/C) was shown to be highly versatile and very

  14. Differential gene expression in response to copper in Acidithiobacillus ferrooxidans strains possessing dissimilar copper resistance.

    PubMed

    Wu, Xueling; Hu, Qi; Hou, Dongmei; Miao, Bo; Liu, Xueduan

    2010-01-01

    Locus afe_0454 from Acidithiobacillus ferrooxidans (At.ferrooxidans) is annotated as related to copper resistance in The Institute for Genomic Research database. In our study, two At.ferrooxidans strains, 26(#) and DC, with different levels of copper ion resistance were isolated from acid mine drainages at two major copper mines in China, and their copper-resistance capacity was determined. The 26(#) strain had a copper-tolerance level of 0.22 mol/L, whereas the DC strain had a lower copper-tolerance level of 0.04 mol/L. The mutant 26(#) was generated from strain 26(#), and its copper-tolerance level was 0.25 mol/L. Using real-time quantitative reverse transcription polymerase chain reaction, differential expression of the afe_0454 gene during copper ion stress of these three strains was investigated. The results showed that the expression of afe_0454 was increased under copper ion stress, indicating that the afe_0454 gene is sensitive to copper levels. Furthermore, the afe_0454 gene expression ratio varied in the different copper-resistant strains. Gene expression was highest in the highest copper-resistant strain. The deduced amino acid sequence of the afe_0454 gene was 56.87% non-polar, indicating the AFE_0454 protein was hydrophobic. Searching with the AFE_0454 protein in The Institute for Genomic Research database showed that the structure of the copper resistance protein D (CopD), which transports copper ions outside of the cell, had the highest sequence identity (46%). Bioinformatics analysis showed that the AFE_0454 protein has eight transmembrane helixes and was predicted to be localized to the plasma membrane. These results strongly suggested that the AFE_0454 protein is likely a transmembrane protein and might be directly involved in copper ion resistance.

  15. Energy and materials flows in the copper industry

    SciTech Connect

    Gaines, L.L.

    1980-12-01

    The copper industry comprises both the primary copper industry, which produces 99.9%-pure copper from copper ore, and the secondary copper industry, which salvages and recycles copper-containing scrap metal to extract pure copper or copper alloys. The United States uses about 2 million tons of copper annually, 60% of it for electrical applications. Demand is expected to increase less than 4% annually for the next 20 years. The primary copper industry is concentrated in the Southwest; Arizona produced 66% of the 1979 total ore output. Primary production uses about 170 x 10/sup 12/ Btu total energy annually (about 100 x 10/sup 6/ Btu/ton pure copper produced from ore). Mining and milling use about 60% of the total consumption, because low-grade ore (0.6% copper) is now being mined. Most copper is extracted by smelting sulfide ores, with concomitant production of sulfur dioxide. Clean air regulations will require smelters to reduce sulfur emissions, necessitating smelting process modifications that could also save 20 x 10/sup 12/ Btu (10 x 10/sup 6/ Btu/ton of copper) in smelting energy. Energy use in secondary copper production averages 20 x 10/sup 6/ Btu/ton of copper. If all copper products were recycled, instead of the 30% now salvaged, the energy conservation potential would be about one-half the total energy consumption of the primary copper industry.

  16. A Copper (II) Aspirinate Project for the General Chemistry Laboratory

    ERIC Educational Resources Information Center

    Dudek, Emily

    1977-01-01

    Describes an experiment that involves the synthesis of copper (II) aspirinate and the analysis of copper content in the product using electrogravimetric, spectrophotometric, and titrimetric methods. (MLH)

  17. Synthesis of copper nanoparticles by electrolysis of DNA utilizing copper as sacrificial anode.

    PubMed

    Singh, Dinesh Pratap; Srivastava, Onkar Nath

    2007-06-01

    Copper nanoparticles have been synthesized by anodic oxidation through a simple electrolysis process employing de-oxy ribonucleic acid (DNA) as electrolyte. Platinum was taken as cathode and copper as anode. The applied voltage was 4 V and the electrolysis was performed for duration of 1 h. The copper nanoparticles were prepared in situ from the electron beam irradiation on residues of electrolyte consisting of DNA and copper particles: DNA (Cu) complexes. The size of the nanoparticles ranges between 5-50 nm. A tentative explanation has been given for the formation of copper nanoparticles.

  18. Synthesis of Copper/Copper-Oxide Nanoparticles: Optical and Structural Characterizations

    SciTech Connect

    Swarnkar, R. K.; Singh, S. C.; Gopal, R.

    2009-06-29

    In the present study, we have synthesized copper/copper-oxide nanoparticles by laser ablation of copper metal in aqueous solution of sodium dodecyl sulfate. The focused output of 1064 nm wavelength of pulsed Nd:YAG laser is used for ablation. The synthesized nanoparticles are characterized by UV-visible absorption, X-ray diffraction, transmission electron microscopy and Raman spectroscopy techniques. The synthesis of copper/copper oxide nanoparticles are confirmed by XRD and Raman studies. The possible mechanism of nanoparticle formation is also discussed.

  19. Annual Copper Mountain Conferences on Multigrid and Iterative Methods, Copper Mountain, Colorado

    SciTech Connect

    McCormick, Stephen F.

    2016-03-25

    This project supported the Copper Mountain Conference on Multigrid and Iterative Methods, held from 2007 to 2015, at Copper Mountain, Colorado. The subject of the Copper Mountain Conference Series alternated between Multigrid Methods in odd-numbered years and Iterative Methods in even-numbered years. Begun in 1983, the Series represents an important forum for the exchange of ideas in these two closely related fields. This report describes the Copper Mountain Conference on Multigrid and Iterative Methods, 2007-2015. Information on the conference series is available at http://grandmaster.colorado.edu/~copper/.

  20. Geomorphology of the lower Copper River, Alaska

    USGS Publications Warehouse

    Brabets, Timothy P.

    1997-01-01

    The Copper River, located in southcentral Alaska, drains an area of more than 24,000 square miles. About 30 miles above its mouth, this large river enters Miles Lake, a proglacial lake formed by the retreat of Miles Glacier. Downstream from the outlet of Miles Lake, the Copper River flows past the face of Childs Glacier before it enters a large, broad, alluvial flood plain. The Copper River Highway traverses this flood plain and in 1995, 11 bridges were located along this section of the highway. These bridges cross parts of the Copper River and in recent years, some of these bridges have sustained serious damage due to the changing course of the Copper River. Although the annual mean discharge of the lower Copper River is 57,400 cubic feet per second, most of the flow occurs during the summer months from snowmelt, rainfall, and glacial melt. Approximately every six years, an outburst flood from Van Cleve Lake, a glacier-dammed lake formed by Miles Glacier, releases approximately 1 million acre-feet of water into the Copper River. When the outflow rate from Van Cleve Lake reaches it peak, the flow of the Copper River will increase between 150,000 to 190,000 cubic feet per second. Data collected by bedload sampling and continuous seismic reflection indicated that Miles Lake traps virtually all the bedload being transported by the Copper River as it enters the lake from the north. The reservoir-like effect of Miles Lake results in the armoring of the channel of the Copper River downstream from Miles Lake, past Childs Glacier, until it reaches the alluvial flood plain. At this point, bedload transport begins again. The lower Copper River transports 69 million tons per year of suspended sediment, approximately the same quantity as the Yukon River, which drains an area of more than 300,000 square miles. By correlating concurrent flows from a long-term streamflow-gaging station on the Copper River with a short-term streamflow-gaging station at the outlet of Miles Lake

  1. Geomorphology of the lower Copper River, Alaska

    USGS Publications Warehouse

    Brabets, T.P.

    1996-01-01

    The Copper River, located in southcentral Alaska, drains an area of more than 24,000 square miles. About 30 miles above its mouth, this large river enters Miles Lake, a proglacial lake formed by the retreat of Miles Glacier. Downstream from the outlet of Miles Lake, the Copper River flows past the face of Childs Glacier before it enters a large, broad, alluvial flood plain. The Copper River Highway traverses this flood plain and in 1996, 11 bridges were located along this section of the highway. These bridges cross parts or all of the Copper River and in recent years, some of these bridges have sustained serious damage due to the changing course of the Copper River. Although the annual mean discharge of the lower Copper River is 57,400 cubic feet per second, most of the flow occurs during the summer months from snowmelt, rainfall, and glacial melt. Approximately every six years, an outburst flood from Van Cleve Lake, a glacier-dammed lake formed by Miles Glacier, releases approximately 1 million acre-feet of water into the Copper River. At the peak outflow rate from Van Cleve Lake, the flow of the Copper River will increase an additional 140,000 and 190,000 cubic feet per second. Bedload sampling and continuous seismic reflection were used to show that Miles Lake traps virtually all the bedload being transported by the Copper River as it enters the lake from the north. The reservoir-like effect of Miles Lake results in the armoring of the channel of the Copper River downstream from Miles Lakes, past Childs Glacier, until it reaches the alluvial flood plain. At this point, bedload transport begins again. The lower Copper River transports 69 million tons per year of suspended sediment, approximately the same quantity as the Yukon River, which drains an area of more than 300,000 square miles. By correlating concurrent flows from a long-term streamflow- gaging station on the Copper River with a short-term streamflow-gaging station at the outlet of Miles Lake, long

  2. Increased blood and urine copper after residential exposure to copper naphthenate

    SciTech Connect

    Bluhm, R.E.; Welch, L.; Branch, R.A. )

    1992-01-01

    Despite widespread industrial use of copper naphthenate, there are no reports of the relationship of copper naphthenate and copper absorption in humans or animals. We report a family of three individuals who lived in a home where copper naphthenate was sprayed on the inner foundation. Subsequently, these individuals developed non-specific complaints. In two of these individuals, serum copper levels were elevated when first measured months after copper naphthenate was sprayed in the home. A gradual decline over several years in urine and serum copper levels was observed in the individual who maintained follow-up. It is not known if symptoms reflected exposure to naphthenate, the solvent vehicle, volatilized copper, or the stress of exposure to a malodorous compound perceived as toxic. Exposure to copper naphthenate may be another cause of an elevated serum and urine copper level but the interpretation of these levels as normal' or toxic' requires additional study for clarification. This report suggests the need for further study of the absorption and relative toxicity of copper naphthenate.

  3. Potentially novel copper resistance genes in copper-enriched activated sludge revealed by metagenomic analysis.

    PubMed

    Li, Li-Guan; Cai, Lin; Zhang, Xu-Xiang; Zhang, Tong

    2014-12-01

    In this study, we utilized the Illumina high-throughput metagenomic approach to investigate diversity and abundance of both microbial community and copper resistance genes (CuRGs) in activated sludge (AS) which was enriched under copper selective stress up to 800 mg/L. The raw datasets (~3.5 Gb for each sample, i.e., the copper-enriched AS and the control AS) were merged and normalized for the BLAST analyses against the SILVA SSU rRNA gene database and self-constructed copper resistance protein database (CuRD). Also, the raw metagenomic sequences were assembled into contigs and analyzed based on Open Reading Frames (ORFs) to identify potentially novel copper resistance genes. Among the different resistance systems for copper detoxification under the high copper stress condition, the Cus system was the most enriched system. The results also indicated that genes encoding multi-copper oxidase played a more important role than those encoding efflux proteins. More significantly, several potentially novel copper resistance ORFs were identified by Pfam search and phylogenic analysis. This study demonstrated a new understanding of microbial-mediated copper resistance under high copper stress using high-throughput shotgun sequencing technique.

  4. Treatment of Wilson's disease with zinc. II. Validation of oral /sup 64/copper with copper balance

    SciTech Connect

    Hill, G.M.; Brewer, G.J.; Juni, J.E.; Prasad, A.S.; Dick, R.D.

    1986-12-01

    The efficacy of zinc as a therapeutic agent to control copper balance in Wilson's disease patients has been previously documented with balance studies. In an attempt to develop a simpler and faster tool for evaluating the adequacy of zinc therapy, a technique that measures the uptake into blood of a small oral dose of /sup 64/copper was studied in conjunction with copper balance. The mean peak /sup 64/copper uptake into blood of nine Wilson's disease patients on D-penicillamine, trien, or no medication was 6.04 +/- 2.74%, comparable with normal controls. Seven patients on zinc therapy had a markedly and significantly reduced mean uptake of 0.79 +/- 1.05% after treatment. The data demonstrate that the prevention of copper uptake into blood in Wilson's disease patients by zinc therapy can be evaluated by /sup 64/copper uptake and that peak uptakes of less than 1% occur in patients with neutral or negative copper balance.

  5. The distribution of copper in neonatal mottled mutant mice after exposure to copper and penicillamine

    SciTech Connect

    Hunt, D.M.; Port, A.E.

    1982-08-01

    Tissue copper levels of brindled (Mo/sup br/) mice and normal littermates after single and repeated dosing with CuCl/sub 2/ and/or D-penicillamine are examined, together with a study of the cytosol distribution of copper after CuCl/sub 2/ treatment. The results confirm that the mutant mouse kidney is capable of extensive copper accumulation in association with the low MW copper-binding protein. Deficient tissues such as brain, heart and spleen are able to sequester sufficient of the exogenous copper to raise their levels to the normal control level, whereas mutant liver levels, even after copper treatment, remain below normal, indicating that the Mo gene affects the ability of the liver to retain copper.

  6. Regulation of gemma formation in the copper moss Scopelophila cataractae by environmental copper concentrations.

    PubMed

    Nomura, Toshihisa; Hasezawa, Seiichiro

    2011-09-01

    Considerable attention has recently been focused on the use of hyperaccumulator plants for the phytoremediation of soils contaminated with heavy metals. The moss, Scopelophila cataractae (Mitt.) Broth., is a typical hyperaccumulator that is usually observed only in copper-rich environments and which accumulates high concentrations of copper in its tissues. However, many of the physiological processes and mechanisms for metal hyperaccumulation in S. cataractae remain unknown. To address this issue, we examined the mechanisms regulating gemma formation, which is considered the main strategy by which S. cataractae relocates to new copper-rich areas. From this study we found that treatment of S. cataractae with high concentrations of copper suppressed gemma formation but promoted protonemal growth. The suppressive effect was not observed by treatment with heavy metals other than copper. These results suggest the importance of copper-sensitive asexual reproduction in the unique life strategy of the copper moss, S. cataractae.

  7. Inborn errors of copper metabolism

    PubMed Central

    KALER, STEPHEN G.

    2014-01-01

    SUMMARY Wilson disease, Menkes disease, occipital horn syndrome, and X-linked distal hereditary motor neuropathy are genetic disorders of copper metabolism that span a broad spectrum of neurological dysfunction (Table 180.1). The occurrence of these disorders indicates the fundamental importance of ATP7A and ATP7B. Further research to clarify the mechanisms suggested by these clinical and biochemical phenotypes may yield insight about the roles of ATP7A and ATP7B in neuronal cells, and lead to improved treatments. PMID:23622398

  8. Common Sense Copper and RF Guns

    SciTech Connect

    Mulhollan, G.

    2005-01-18

    The purpose of this document is to gather together both fundamental information on copper and on the cleaning and operation of copper in RF gun structures. While incomplete, this is a living document and will be added to and updated as necessary.

  9. COPPER PITTING AND PINHOLE LEAK RESEARCH STUDY

    EPA Science Inventory

    Localized copper corrosion or pitting is a significant problem at many water utilities across the United States. Copper pinhole leak problems resulting from extensive pitting are widely under reported. Given the sensitive nature of the problem, extent of damage possible, costs o...

  10. NON-UNIFORM COPPER CORROSION: RESEARCH UPDATE

    EPA Science Inventory

    Pinhole leaks due to copper pitting corrosion are a major cause of home plumbing failure. This study documents cases of copper pitting corrosion found in homes supplied by Butler County Environmental Services in Ohio. SEM. XRD, and optical microscopy were used to document pit s...

  11. Copper deficiency in calves in northcentral Manitoba.

    PubMed

    Smart, M E; Gudmundson, J; Brockman, R P; Cymbaluk, N; Doige, C

    1980-12-01

    Four seven month old Simmental calves were examined because of unthriftiness, a persistent cough, stiffness and lameness. The calves had gastrointestinal and pulmonary parasitism. Analysis of the blood copper levels of these calves and of cows and calves on the farm indicated a generalized deficiency. Only the calves affected with parasitism showed signs of clinical copper deficiency.

  12. Copper Regulates Cyclic AMP-Dependent Lipolysis

    PubMed Central

    Krishnamoorthy, Lakshmi; Cotruvo, Joseph A.; Chan, Jefferson; Kaluarachchi, Harini; Muchenditsi, Abigael; Pendyala, Venkata S.; Jia, Shang; Aron, Allegra T.; Ackerman, Cheri M.; Vander Wal, Mark N.; Guan, Timothy; Smaga, Lukas P.; Farhi, Samouil L.; New, Elizabeth J.; Lutsenko, Svetlana; Chang, Christopher J.

    2016-01-01

    Cell signaling relies extensively on dynamic pools of redox-inactive metal ions such as sodium, potassium, calcium, and zinc, but their redox-active transition metal counterparts such as copper and iron have been studied primarily as static enzyme cofactors. Here we report that copper is an endogenous regulator of lipolysis, the breakdown of fat, which is an essential process in maintaining the body's weight and energy stores. Utilizing a murine model of genetic copper misregulation, in combination with pharmacological alterations in copper status and imaging studies in a 3T3-L1 white adipocyte model, we demonstrate that copper regulates lipolysis at the level of the second messenger, cyclic AMP (cAMP), by altering the activity of the cAMP-degrading phosphodiesterase PDE3B. Biochemical studies of the copper-PDE3B interaction establish copper-dependent inhibition of enzyme activity and identify a key conserved cysteine residue within a PDE3-specific loop that is essential for the observed copper-dependent lipolytic phenotype. PMID:27272565

  13. Fetal polyol metabolism in copper deficiency

    SciTech Connect

    Fields, M.; Lewis, C.G.; Beal, T. )

    1989-02-09

    Since pregnant rats consuming fructose, copper deficient diets fail to give birth, the relationship between maternal copper deficiency, polyol metabolism and fetal mortality was investigated. Forty Sprague-Dawley rats were fed from conception one of the following diets: fructose, copper deficient; fructose, copper adequate; starch, copper deficient or starch, copper adequate. The deficient diets contained 0.6 ug Cu and the adequate 6.0 ug Cu/g diet. Pregnancy was terminated at day 19 of gestation. Glucose, sorbitol and fructose were measured in maternal blood, placenta and fetal liver. Fructose consumption during pregnancy resulted in higher levels of fructose and sorbitol in maternal blood when compared to starch. In the fructose dietary groups, the placenta and fetal liver contained extremely high levels of glucose, fructose and sorbitol compared to the corresponding metabolites from the starch dietary groups. Copper deficiency further elevated fructose and sorbitol concentrations in the placenta and fetal liver respectively. Since high tissue levels of glucose, fructose and sorbitol have been shown to have deleterious effects on cellular metabolism, these data suggest that when fructose was fed during pregnancy the combination of an aberration of carbohydrate metabolism with copper deficiency could be responsible for the pathology and mortality of the developing fetus.

  14. Differential bacteriophage mortality on exposure to copper.

    PubMed

    Li, Jinyu; Dennehy, John J

    2011-10-01

    Many studies report that copper can be used to control microbial growth, including that of viruses. We determined the rates of copper-mediated inactivation for a wide range of bacteriophages. We used two methods to test the effect of copper on bacteriophage survival. One method involved placing small volumes of bacteriophage lysate on copper and stainless steel coupons. Following exposure, metal coupons were rinsed with lysogeny broth, and the resulting fluid was serially diluted and plated on agar with the corresponding bacterial host. The second method involved adding copper sulfate (CuSO(4)) to bacteriophage lysates to a final concentration of 5 mM. Aliquots were removed from the mixture, serially diluted, and plated with the appropriate bacterial host. Significant mortality was observed among the double-stranded RNA (dsRNA) bacteriophages Φ6 and Φ8, the single-stranded RNA (ssRNA) bacteriophage PP7, the ssDNA bacteriophage ΦX174, and the dsDNA bacteriophage PM2. However, the dsDNA bacteriophages PRD1, T4, and λ were relatively unaffected by copper. Interestingly, lipid-containing bacteriophages were most susceptible to copper toxicity. In addition, in the first experimental method, the pattern of bacteriophage Φ6 survival over time showed a plateau in mortality after lysates dried out. This finding suggests that copper's effect on bacteriophage is mediated by the presence of water.

  15. Lead and Copper Control 101-slides

    EPA Science Inventory

    This presentation is an overview of the most important water treatment strategies for the control of lead and copper release from drinking water corrosion. In addition to the sections specifically on lead and copper treatment, sections are included that cover sampling to find le...

  16. Fluidized-bed copper oxide process

    SciTech Connect

    Shah, P.P.; Takahashi, G.S.; Leshock, D.G.

    1991-10-14

    The fluidized-bed copper oxide process was developed to simultaneously remove sulfur dioxide and nitrogen oxide contaminants from the flue gas of coal-fired utility boilers. This dry and regenerable process uses a copper oxide sorbent in a fluidized-bed reactor. Contaminants are removed without generating waste material. (VC)

  17. Response of gram-positive bacteria to copper stress.

    PubMed

    Solioz, Marc; Abicht, Helge K; Mermod, Mélanie; Mancini, Stefano

    2010-01-01

    The Gram-positive bacteria Enterococcus hirae, Lactococcus lactis, and Bacillus subtilis have received wide attention in the study of copper homeostasis. Consequently, copper extrusion by ATPases, gene regulation by copper, and intracellular copper chaperoning are understood in some detail. This has provided profound insight into basic principles of how organisms handle copper. It also emerged that many bacterial species may not require copper for life, making copper homeostatic systems pure defense mechanisms. Structural work on copper homeostatic proteins has given insight into copper coordination and bonding and has started to give molecular insight into copper handling in biological systems. Finally, recent biochemical work has shed new light on the mechanism of copper toxicity, which may not primarily be mediated by reactive oxygen radicals.

  18. Effects of pattern characteristics on copper CMP

    NASA Astrophysics Data System (ADS)

    Wenbiao, Ruan; Lan, Chen; Zhigang, Li; Tianchun, Ye

    2009-04-01

    Copper chemical mechanical polishing (CMP) is influenced by geometric characteristics such as line width and pattern density, as well as by the more obvious parameters such as slurry chemistry, pad type, polishing pressure and rotational speed. Variations in the copper thickness across each die and across the wafer can impact the circuit performance and reduce the yield. In this paper, we propose a modeling method to simulate the polishing behavior as a function of layout pattern factors. Under the same process conditions, the pattern density, the line width and the line spacing have a strong influence on copper dishing, dielectric erosion and topography. The test results showed: the wider the copper line or the spacing, the higher the copper dishing; the higher the density, the higher the dielectric erosion; the dishing and erosion increase slowly as a function of increasing density and go into saturation when the density is more than 0.7.

  19. Copper accumulation in channel catfish (Ictalurus punctatus) exposed to water borne copper sulfate

    SciTech Connect

    Hobbs, M.; Griffin, B.; Schlenk, D.; Kadlubar, F.; Brand, C.D.

    1995-12-31

    Liver and axial muscle of channel catfish (Ictalurus punctatus) was analyzed for residual copper after exposure to water borne copper sulfate. Copper sulfate was continuously introduced into well water in three fiber glass tanks to achieve 1.7 mg/L, 2.7 mg/L and 3.6 mg/L copper sulfate concentrations in exposure waters. Milli-Q quality water was metered into a fourth tank at the same rate for unexposed fish. Actual levels of copper in exposure waters were determined by daily sampling and analysis by graphite furnace atomic absorption spectrophotometry (GFAA). Tissue samples were taken from six fish from each of the exposed and unexposed tanks at two-week intervals, Samples were collected until tissue analysis indicated an equilibrium had been established between the uptake and elimination in both the muscle and liver tissue. Elimination was followed until a clear rate of deputation could be established. Samples were digested in nitric acid in a micro wave digestor and analyzed by GFAA. Results of tissue analysis will be presented to demonstrate bioaccumulation and the effect of copper concentration, length of copper exposure, and gender on copper uptake, establishment of tissue:environmental copper equilibrium, and rate of copper elimination following exposure.

  20. Effect of chelators on copper metabolism and copper pools in mouse hepatocytes

    SciTech Connect

    McArdle, H.J.; Gross, S.M.; Creaser, I.; Sargeson, A.M.; Danks, D.M.

    1989-04-01

    Disorders of copper storage are usually treated by chelation therapy. It is generally thought that the chelators act by mobilizing copper from the liver, hence allowing excretion in the urine. This paper has examined the effect of chelators on copper uptake and storage in mouse hepatocytes. Penicillamine, a clinically important chelator, does not block the uptake of copper or remove copper from hepatocytes. Two other copper chelators, sar and diamsar, which form very stable and kinetically inert Cu2+ complexes by encapsulating the metal ion in an organic cage, were shown to block copper accumulation by the cells and to remove up to 80% of cell-associated copper. They also removed most (approximately 80%) of the /sup 64/Cu accumulated by the cells in 30 min, but released only a small percentage (less than 20%) of that accumulated over 18 h. The results show that copper in the hepatocyte can be divided into at least two pools, an easily accessible one, and another, not removable even after long-term incubation with any of the chelators. Most of the copper normally found in the cell appeared to be associated with the former pool.

  1. Molecular Responses of Mouse Macrophages to Copper and Copper Oxide Nanoparticles Inferred from Proteomic Analyses*

    PubMed Central

    Triboulet, Sarah; Aude-Garcia, Catherine; Carrière, Marie; Diemer, Hélène; Proamer, Fabienne; Habert, Aurélie; Chevallet, Mireille; Collin-Faure, Véronique; Strub, Jean-Marc; Hanau, Daniel; Van Dorsselaer, Alain; Herlin-Boime, Nathalie; Rabilloud, Thierry

    2013-01-01

    The molecular responses of macrophages to copper-based nanoparticles have been investigated via a combination of proteomic and biochemical approaches, using the RAW264.7 cell line as a model. Both metallic copper and copper oxide nanoparticles have been tested, with copper ion and zirconium oxide nanoparticles used as controls. Proteomic analysis highlighted changes in proteins implicated in oxidative stress responses (superoxide dismutases and peroxiredoxins), glutathione biosynthesis, the actomyosin cytoskeleton, and mitochondrial proteins (especially oxidative phosphorylation complex subunits). Validation studies employing functional analyses showed that the increases in glutathione biosynthesis and in mitochondrial complexes observed in the proteomic screen were critical to cell survival upon stress with copper-based nanoparticles; pharmacological inhibition of these two pathways enhanced cell vulnerability to copper-based nanoparticles, but not to copper ions. Furthermore, functional analyses using primary macrophages derived from bone marrow showed a decrease in reduced glutathione levels, a decrease in the mitochondrial transmembrane potential, and inhibition of phagocytosis and of lipopolysaccharide-induced nitric oxide production. However, only a fraction of these effects could be obtained with copper ions. In conclusion, this study showed that macrophage functions are significantly altered by copper-based nanoparticles. Also highlighted are the cellular pathways modulated by cells for survival and the exemplified cross-toxicities that can occur between copper-based nanoparticles and pharmacological agents. PMID:23882024

  2. Evaluation of copper resistant bacteria from vineyard soils and mining waste for copper biosorption

    PubMed Central

    Andreazza, R.; Pieniz, S.; Okeke, B.C.; Camargo, F.A.O

    2011-01-01

    Vineyard soils are frequently polluted with high concentrations of copper due application of copper sulfate in order to control fungal diseases. Bioremediation is an efficient process for the treatment of contaminated sites. Efficient copper sorption bacteria can be used for bioremoval of copper from contaminated sites. In this study, a total of 106 copper resistant bacteria were examined for resistance to copper toxicity and biosorption of copper. Eighty isolates (45 from vineyard Mollisol, 35 from Inceptisol) were obtained from EMBRAPA (Empresa Brasileira de Pesquisa Agropecuária) experimental station, Bento Gonçalves, RS, Brazil (29°09′53.92″S and 51°31′39.40″W) and 26 were obtained from copper mining waste from Caçapava do Sul, RS, Brazil (30°29′43.48″S and 53′32′37.87W). Based on resistance to copper toxicity and biosorption, 15 isolates were identified by 16S rRNA gene sequencing. Maximal copper resistance and biosorption at high copper concentration were observed with isolate N2 which removed 80 mg L−1 in 24 h. Contrarily isolate N11 (Bacillus pumilus) displayed the highest specific copper biosorption (121.82 mg/L/OD unit in 24 h). GenBank MEGABLAST analysis revealed that isolate N2 is 99% similar to Staphylococcus pasteuri. Results indicate that several of our isolates have potential use for bioremediation treatment of vineyards soils and mining waste contaminated with high copper concentration. PMID:24031606

  3. 19 CFR 10.98 - Copper-bearing fluxing material.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 1 2011-04-01 2011-04-01 false Copper-bearing fluxing material. 10.98 Section 10... Material § 10.98 Copper-bearing fluxing material. (a) For the purpose of this section, ores usable as a... copper. (b) (c) There shall be filed in connection with the entry of such copper-bearing ores, either...

  4. 19 CFR 10.98 - Copper-bearing fluxing material.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Copper-bearing fluxing material. 10.98 Section 10... Material § 10.98 Copper-bearing fluxing material. (a) For the purpose of this section, ores usable as a... copper. (b) (c) There shall be filed in connection with the entry of such copper-bearing ores, either...

  5. 19 CFR 10.98 - Copper-bearing fluxing material.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 1 2013-04-01 2013-04-01 false Copper-bearing fluxing material. 10.98 Section 10... Material § 10.98 Copper-bearing fluxing material. (a) For the purpose of this section, ores usable as a... copper. (b) (c) There shall be filed in connection with the entry of such copper-bearing ores, either...

  6. 19 CFR 10.98 - Copper-bearing fluxing material.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 1 2014-04-01 2014-04-01 false Copper-bearing fluxing material. 10.98 Section 10... Material § 10.98 Copper-bearing fluxing material. (a) For the purpose of this section, ores usable as a... copper. (b) (c) There shall be filed in connection with the entry of such copper-bearing ores, either...

  7. 19 CFR 10.98 - Copper-bearing fluxing material.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 1 2012-04-01 2012-04-01 false Copper-bearing fluxing material. 10.98 Section 10... Material § 10.98 Copper-bearing fluxing material. (a) For the purpose of this section, ores usable as a... copper. (b) (c) There shall be filed in connection with the entry of such copper-bearing ores, either...

  8. THE IMPACT OF ORTHOPHOSPHATE ON COPPER CORROSION AND CHLORINE DEMAND

    EPA Science Inventory

    In 1991, EPA promulgated the Lead and Copper Rule, which established a copper action level of 1.3 mg/L in a 1-liter, first-draw sample collected from the consumer’s tap. Excessive corrosion of copper can lead to elevated copper levels at the consumer's tap, and in some cases, can...

  9. 49 CFR 192.125 - Design of copper pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Design of copper pipe. 192.125 Section 192.125... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Pipe Design § 192.125 Design of copper pipe. (a) Copper... hard drawn. (b) Copper pipe used in service lines must have wall thickness not less than that...

  10. 49 CFR 192.125 - Design of copper pipe.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Design of copper pipe. 192.125 Section 192.125... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Pipe Design § 192.125 Design of copper pipe. (a) Copper... hard drawn. (b) Copper pipe used in service lines must have wall thickness not less than that...

  11. 49 CFR 192.125 - Design of copper pipe.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Design of copper pipe. 192.125 Section 192.125... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Pipe Design § 192.125 Design of copper pipe. (a) Copper... hard drawn. (b) Copper pipe used in service lines must have wall thickness not less than that...

  12. 49 CFR 192.125 - Design of copper pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Design of copper pipe. 192.125 Section 192.125... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Pipe Design § 192.125 Design of copper pipe. (a) Copper... hard drawn. (b) Copper pipe used in service lines must have wall thickness not less than that...

  13. 49 CFR 192.125 - Design of copper pipe.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Design of copper pipe. 192.125 Section 192.125... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Pipe Design § 192.125 Design of copper pipe. (a) Copper... hard drawn. (b) Copper pipe used in service lines must have wall thickness not less than that...

  14. Recombination activity of copper in silicon

    NASA Astrophysics Data System (ADS)

    Sachdeva, R.; Istratov, A. A.; Weber, E. R.

    2001-10-01

    The carrier recombination activity of copper in n-type and p-type silicon has been investigated. The minority carrier diffusion length has been found to decrease monotonically with increasing copper concentration in n Si and to exhibit a step-like behavior in p-type silicon at Cu concentrations above a certain critical level. It is suggested that the impact of copper on the minority carrier diffusion length is determined by the formation of copper precipitates. This process is retarded in perfect silicon due to the large lattice mismatch between Cu3Si and the silicon lattice and even more retarded in p Si, due to electrostatic repulsion effects between the positively charged copper precipitates and interstitial copper ions. Comparison of the impact of Cu on minority carrier diffusion length obtained with p-Si samples of different resistivity confirmed the electrostatic model. Studies of the impact of copper on minority carrier diffusion length in samples with internal gettering sites indicated that they provide heterogeneous nucleation sites for Cu precipitation at subcritical Cu concentration. Above a certain threshold of Cu concentration, the bulk recombination activity is dominated by quasihomogeneous formation of Cu precipitates, a process that is not detectably affected by the presence of oxide precipitates.

  15. Copper Delivery to Chloroplast Proteins and its Regulation.

    PubMed

    Aguirre, Guadalupe; Pilon, Marinus

    2015-01-01

    Copper is required for photosynthesis in chloroplasts of plants because it is a cofactor of plastocyanin, an essential electron carrier in the thylakoid lumen. Other chloroplast copper proteins are copper/zinc superoxide dismutase and polyphenol oxidase, but these proteins seem to be dispensable under conditions of low copper supply when transcripts for these proteins undergo microRNA-mediated down regulation. Two ATP-driven copper transporters function in tandem to deliver copper to chloroplast compartments. This review seeks to summarize the mechanisms of copper delivery to chloroplast proteins and its regulation. We also delineate some of the unanswered questions that still remain in this field.

  16. Copper Delivery to Chloroplast Proteins and its Regulation

    PubMed Central

    Aguirre, Guadalupe; Pilon, Marinus

    2016-01-01

    Copper is required for photosynthesis in chloroplasts of plants because it is a cofactor of plastocyanin, an essential electron carrier in the thylakoid lumen. Other chloroplast copper proteins are copper/zinc superoxide dismutase and polyphenol oxidase, but these proteins seem to be dispensable under conditions of low copper supply when transcripts for these proteins undergo microRNA-mediated down regulation. Two ATP-driven copper transporters function in tandem to deliver copper to chloroplast compartments. This review seeks to summarize the mechanisms of copper delivery to chloroplast proteins and its regulation. We also delineate some of the unanswered questions that still remain in this field. PMID:26793223

  17. Copper accumulation by stickleback nests containing spiggin.

    PubMed

    Pinho, G L L; Martins, C M G; Barber, I

    2016-07-01

    The three-spined stickleback is a ubiquitous fish of marine, brackish and freshwater ecosystems across the Northern hemisphere that presents intermediate sensitivity to copper. Male sticklebacks display a range of elaborate reproductive behaviours that include nest construction. To build the nests, each male binds nesting material together using an endogenous glycoprotein nesting glue, known as 'spiggin'. Spiggin is a cysteine-rich protein and, therefore, potentially binds heavy metals present in the environment. The aim of this study was to investigate the capacity of stickleback nests to accumulate copper from environmental sources. Newly built nests, constructed by male fish from polyester threads in laboratory aquaria, were immersed in copper solutions ranging in concentration from 21.1-626.6 μg Cu L(-1). Bundles of polyester threads from aquaria without male fish were also immersed in the same copper solutions. After immersion, nests presented higher amounts of copper than the thread bundles, indicating a higher capacity of nests to bind this metal. A significant, positive correlation between the concentration of copper in the exposure solution and in the exposed nests was identified, but there was no such relationship for thread bundles. Since both spiggin synthesis and male courtship behaviour are under the control of circulating androgens, we predicted that males with high courtship scores would produce and secrete high levels of the spiggin protein. In the present study, nests built by high courtship score males accumulated more copper than those built by low courtship score males. Considering the potential of spiggin to bind metals, the positive relationship between fish courtship and spiggin secretion seems to explain the higher amount of copper on the nests from the fish showing high behaviour scores. Further work is now needed to determine the consequences of the copper binding potential of spiggin in stickleback nests for the health and survival of

  18. The alteration of copper homeostasis in inflammation induced by lipopolysaccharides.

    PubMed

    Han, Ming; Lin, Zhexuan; Zhang, Yuan

    2013-08-01

    Significant changes of copper homeostasis were triggered by lipopolysaccharides, which result in systemic inflammatory response and contribute to hepatic injury. Administration of lipopolysaccharides resulted in the increase of plasma "free" copper and total copper concentrations, whereas, the decrease of "free" copper and total copper contents in liver tissue. Copper-associated proteins were detected and showed a down-regulation of X-linked inhibitor of apoptosis protein, and up-regulation of copper metabolism domain containing 1 and copper transporter 1. The alteration of these proteins would lower the apoptotic threshold. Meanwhile, the increasing of circulation copper might cause oxidative injury through Fenton reaction and contribute to tissue injury. Our findings underscored the possibility that these changes in systemic copper homeostasis might provide a novel insight of the characteristic of the acute phase of inflammatory response and the underlying influence on tissue injury.

  19. Copper localization, elemental content, and thallus colour in the copper hyperaccumulator lichen Lecanora sierra from California

    USGS Publications Warehouse

    Purvis, O.W.; Bennett, J.P.; Spratt, J.

    2011-01-01

    An unusual dark blue-green lichen, Lecanora sierrae, was discovered over 30 years ago by Czehura near copper mines in the Lights Creek District, Plumas County, Northern California. Using atomic absorption spectroscopy, Czehura found that dark green lichen samples from Warren Canyon contained 4% Cu in ash and suggested that its colour was due to copper accumulation in the cortex. The present study addressed the hypothesis that the green colour in similar material we sampled from Warren Canyon in 2008, is caused by copper localization in the thallus. Optical microscopy and electron microprobe analysis of specimens of L. sierrae confirmed that copper localization took place in the cortex. Elemental analyses of L. sierrae and three other species from the same localities showed high enrichments of copper and selenium, suggesting that copper selenates or selenites might occur in these lichens and be responsible for the unusual colour.

  20. Copper localization, elemental content, and thallus colour in the copper hyperaccumulator lichen Lecanora sierrae from California

    USGS Publications Warehouse

    Purvis, O.W.; Bennett, J.P.; Spratt, J.

    2011-01-01

    An unusual dark blue-green lichen, Lecanora sierrae, was discovered over 30 years ago by Czehura near copper mines in the Lights Creek District, Plumas County, Northern California. Using atomic absorption spectroscopy, Czehura found that dark green lichen samples from Warren Canyon contained 4% Cu in ash and suggested that its colour was due to copper accumulation in the cortex. The present study addressed the hypothesis that the green colour in similar material we sampled from Warren Canyon in 2008, is caused by copper localization in the thallus. Optical microscopy and electron microprobe analysis of specimens of L. sierrae confirmed that copper localization took place in the cortex. Elemental analyses of L. sierrae and three other species from the same localities showed high enrichments of copper and selenium, suggesting that copper selenates or selenites might occur in these lichens and be responsible for the unusual colour. Copyright ?? 2011 British Lichen Society.

  1. The Role of Copper Chaperone Atox1 in Coupling Redox Homeostasis to Intracellular Copper Distribution

    PubMed Central

    Hatori, Yuta; Lutsenko, Svetlana

    2016-01-01

    Human antioxidant protein 1 (Atox1) is a small cytosolic protein with an essential role in copper homeostasis. Atox1 functions as a copper carrier facilitating copper transfer to the secretory pathway. This process is required for activation of copper dependent enzymes involved in neurotransmitter biosynthesis, iron efflux, neovascularization, wound healing, and regulation of blood pressure. Recently, new cellular roles for Atox1 have emerged. Changing levels of Atox1 were shown to modulate response to cancer therapies, contribute to inflammatory response, and protect cells against various oxidative stresses. It has also become apparent that the activity of Atox1 is tightly linked to the cellular redox status. In this review, we summarize biochemical information related to a dual role of Atox1 as a copper chaperone and an antioxidant. We discuss how these two activities could be linked and contribute to establishing the intracellular copper balance and functional identity of cells during differentiation. PMID:27472369

  2. Copper binding triggers compaction in N-terminal tail of human copper pump ATP7B.

    PubMed

    Mondol, Tanumoy; Åden, Jörgen; Wittung-Stafshede, Pernilla

    2016-02-12

    Protein conformational changes are fundamental to biological reactions. For copper ion transport, the multi-domain protein ATP7B in the Golgi network receives copper from the cytoplasmic copper chaperone Atox1 and, with energy from ATP hydrolysis, moves the metal to the lumen for loading of copper-dependent enzymes. Although anticipated, conformational changes involved in ATP7B's functional cycle remain elusive. Using spectroscopic methods we here demonstrate that the four most N-terminal metal-binding domains in ATP7B, upon stoichiometric copper addition, adopt a more compact arrangement which has a higher thermal stability than in the absence of copper. In contrast to previous reports, no stable complex was found in solution between the metal-binding domains and the nucleotide-binding domain of ATP7B. Metal-dependent movement of the first four metal-binding domains in ATP7B may be a trigger that initiates the overall catalytic cycle.

  3. Copper concentration of liver tissue under long-term copper-histidine therapy in a patient with Menkes disease.

    PubMed

    Kroepfl, T; Mair, E; Deutsch, J; Brunner-Krainz, M; Paschke, E; Plecko, B

    2006-08-01

    Copper-histidine is the treatment of choice in Menkes disease but bears the potential risk of copper overload and induced liver cirrhosis. We report normal copper concentrations of liver tissue over an 8-year treatment period with copper-histidine.

  4. Copper-Exchanged Zeolite L Traps Oxygen

    NASA Technical Reports Server (NTRS)

    Sharma, Pramod K.; Seshan, Panchalam K.

    1991-01-01

    Brief series of simple chemical treatments found to enhance ability of zeolite to remove oxygen from mixture of gases. Thermally stable up to 700 degrees C and has high specific surface area which provides high capacity for adsorption of gases. To increase ability to adsorb oxygen selectively, copper added by ion exchange, and copper-exchanged zeolite reduced with hydrogen. As result, copper dispersed atomically on inner surfaces of zeolite, making it highly reactive to oxygen, even at room temperature. Reactivity to oxygen even greater at higher temperatures.

  5. Nanosecond pulsed laser blackening of copper

    NASA Astrophysics Data System (ADS)

    Tang, Guang; Hourd, Andrew C.; Abdolvand, Amin

    2012-12-01

    Nanosecond (12 ns) pulsed laser processing of copper at 532 nm resulted in the formation of homogenously distributed, highly organized microstructures. This led to the fabrication of large area black copper substrates with absorbance of over 97% in the spectral range from 250 nm to 750 nm, and a broadband absorbance of over 80% between 750 nm and 2500 nm. Optical and chemical analyses of the fabricated black metal are presented and discussed. The employed laser is an industrially adaptable source and the presented technique for fabrication of black copper could find applications in broadband thermal radiation sources, solar energy absorbers, irradiative heat transfer devices, and thermophotovoltaics.

  6. [Biomachining of metal copper by Thiobacillus ferrooxidans].

    PubMed

    Li, Y; Zhang, D; Wu, Y

    2000-06-01

    Thiobacillus ferrooxidans was employed in the biomachining process of metal copper(Cu0). The bacteria growth and the changes of Fe3+ concentration during machining processes have been studied. Biomachining and chemical machining have been compared. The results showed that the concentrations of bacteria and Fe3+ determine the speed of machining copper. The biomachining is more fast that chemical maching because bacteria are able to regenerate Fe3+ oxidizing copper. It was also found that the Cu2+ produced from the machining processes inhibit the growth of bacteria. Cu2+ has to be removed.

  7. Copper: Toxicological relevance and mechanisms

    PubMed Central

    Gaetke, Lisa M.; Chow-Johnson, Hannah S.; Chow, Ching K.

    2015-01-01

    Copper (Cu) is a vital mineral essential for many biological processes. The vast majority of all Cu in healthy humans is associated with enzyme prosthetic groups or bound to proteins. Cu homeostasis is tightly regulated through a complex system of Cu transporters and chaperone proteins. Excess or toxicity of Cu, which is associated with the pathogenesis of hepatic disorder, neurodegenerative changes and other disease conditions, can occur when Cu homeostasis is disrupted. The capacity to initiate oxidative damage is most commonly attributed to Cu-induced cellular toxicity. Recently, altered cellular events, including lipid metabolism, gene expression, alpha-synuclein aggregation, activation of acidic sphingomyelinase and release of ceramide, and temporal and spatial distribution of Cu in hepatocytes, as well as Cu-protein interaction in the nerve system, have been suggested to play a role in Cu toxicity. However, whether these changes are independent of, or secondary to, an altered cellular redox state of Cu remain to be elucidated. PMID:25199685

  8. Purification of human copper, zinc superoxide dismutase by copper chelate affinity chromatography

    SciTech Connect

    Weslake, R.J.; Chesney, S.L.; Petkau, A.; Friesen, A.D.

    1986-05-15

    Copper, zinc superoxide dismutase was isolated from human red blood cell hemolysate by DEAE-Sepharose and copper chelate affinity chromatography. Enzyme preparations had specific activities ranging from 3400 to 3800 U/mg and recoveries were approximately 60% of the enzyme activity in the lysate. Copper chelate affinity chromatography resulted in a purification factor of about 60-fold. The homogeneity of the superoxide dismutase preparation was analyzed by sodium dodecyl sulfate-gel electrophoresis, analytical gel filtration chromatography, and isoelectric focusing.

  9. Effects of stimulation of copper bioleaching on microbial community in vineyard soil and copper mining waste.

    PubMed

    Andreazza, Robson; Okeke, Benedict C; Pieniz, Simone; Bortolon, Leandro; Lambais, Márcio R; Camargo, Flávio A O

    2012-04-01

    Long-term copper application in vineyards and copper mining activities cause heavy metal pollution sites. Such sites need remediation to protect soil and water quality. Bioremediation of contaminated areas through bioleaching can help to remove copper ions from the contaminated soils. Thus, the aim of this work was to evaluate the effects of different treatments for copper bioleaching in two diverse copper-contaminated soils (a 40-year-old vineyard and a copper mining waste) and to evaluate the effect on microbial community by applying denaturing gradient gel electrophoresis (DGGE) of 16S ribosomal DNA amplicons and DNA sequence analysis. Several treatments with HCl, H(2)SO(4), and FeSO(4) were evaluated by stimulation of bioleaching of copper in the soils. Treatments and extractions using FeSO(4) and H(2)SO(4) mixture at 30°C displayed more copper leaching than extractions with deionized water at room temperature. Treatment with H(2)SO(4) supported bioleaching of as much as 120 mg kg(-1) of copper from vineyard soil after 115 days of incubation. DGGE analysis of the treatments revealed that some treatments caused greater diversity of microorganisms in the vineyard soil compared to the copper mining waste. Nucleotide Blast of PCR-amplified fragments of 16S rRNA gene bands from DGGE indicated the presence of Rhodobacter sp., Silicibacter sp., Bacillus sp., Paracoccus sp., Pediococcus sp., a Myxococcales, Clostridium sp., Thiomonas sp., a firmicute, Caulobacter vibrioides, Serratia sp., and an actinomycetales in vineyard soil. Contrarily, Sphingomonas was the predominant genus in copper mining waste in most treatments. Paracoccus sp. and Enterobacter sp. were also identified from DGGE bands of the copper mining waste. Paracoccus species is involved in the copper bioleaching by sulfur oxidation system, liberating the copper bounded in the soils and hence promoting copper bioremediation. Results indicate that stimulation of bioleaching with a combination of FeSO(4

  10. Featured Article: Effect of copper on nuclear translocation of copper chaperone for superoxide dismutase-1

    PubMed Central

    Wang, Lin; Ge, Yan

    2016-01-01

    Copper chaperone for superoxide dismutase-1 (CCS-1), facilitating copper insertion into superoxide dismutase 1 (SOD-1), is present in the nucleus. However, it is unknown how CCS-1 is translocated to the nucleus. The present study was undertaken to determine the effect of copper on nuclear translocation of CCS-1. Human umbilical vein endothelial cells (HUVECs) were subjected to hypoxia, causing an increase in both copper and CCS-1 in the nucleus. Treatment with tetraethylenepentamine (TEPA) not only decreased the total cellular concentration and the nuclear translocation of copper, but also completely suppressed the entry of CCS-1 to the nucleus. On the other hand, siRNA targeting CCS-1 neither inhibited the increase in total concentrations nor blocked the nuclear translocation of copper. This study thus demonstrates that under hypoxia condition, both copper and CCS-1 are transported to the nucleus. The nuclear translocation of CCS-1 is copper dependent, but the nuclear translocation of copper could take place alternatively in a CCS-1-independent pathway. PMID:27190267

  11. Featured Article: Effect of copper on nuclear translocation of copper chaperone for superoxide dismutase-1.

    PubMed

    Wang, Lin; Ge, Yan; Kang, Y James

    2016-08-01

    Copper chaperone for superoxide dismutase-1 (CCS-1), facilitating copper insertion into superoxide dismutase 1 (SOD-1), is present in the nucleus. However, it is unknown how CCS-1 is translocated to the nucleus. The present study was undertaken to determine the effect of copper on nuclear translocation of CCS-1. Human umbilical vein endothelial cells (HUVECs) were subjected to hypoxia, causing an increase in both copper and CCS-1 in the nucleus. Treatment with tetraethylenepentamine (TEPA) not only decreased the total cellular concentration and the nuclear translocation of copper, but also completely suppressed the entry of CCS-1 to the nucleus. On the other hand, siRNA targeting CCS-1 neither inhibited the increase in total concentrations nor blocked the nuclear translocation of copper. This study thus demonstrates that under hypoxia condition, both copper and CCS-1 are transported to the nucleus. The nuclear translocation of CCS-1 is copper dependent, but the nuclear translocation of copper could take place alternatively in a CCS-1-independent pathway.

  12. Reduction of copper sulphate with elemental iron for preparation of copper nanoparticles

    NASA Astrophysics Data System (ADS)

    Nazim, Muhammad

    Reduction of copper sulphate with elemental iron also known as cementation is a well known process used for the recovery of copper for a long time. In this study, the kinetics of the reaction of copper sulphate with iron wire and iron powder has been investigated. The reaction kinetics was studied as a function of different process parameters such as initial concentration, temperature and pH. In this research work, the effects of the above three parameters were studied for both types of iron substrates. It was found that with the iron wire the reaction obeys first order kinetics with respect to copper concentration whereas with the iron powder the order was found to be 1.5. The initial concentration was found to have considerable effect on the reaction kinetics of copper sulphate with elemental iron. The rate of reaction increases with an increase in the initial copper concentration up to a certain level and then decreases for the case of iron wire. However, for the reaction of copper sulphate with iron powder, the reaction rate decreases with an increase in the initial copper concentration. The effect of temperature on the reaction rate of copper sulphate for both types iron substrates (iron wire and iron powder) has also been studied in the temperature range of 23-54ºC. In both the cases, the reaction rate increases with an increase in temperature according to Arrhenius law. The activation energy for the reactions of copper sulphate with iron wire and iron powder was found to be 25.36 kJ/mol and 26.32 kJ/mol, respectively. The copper cementation reaction was found to be suitable to operate at a pH of 2.5-3 for iron wire and a pH of 3-4 for iron powder considering possible inhibition by copper hydroxyl complex formation at higher pH and the possible excess iron consumption by hydrogen reduction at lower pH. The copper particles were produced by the reduction of copper sulphate with elemental iron. The produced copper particles were obtained in the micro to nano

  13. Liver copper concentrations in cull cattle in the UK: are cattle being copper loaded?

    PubMed Central

    Kendall, N. R.; Holmes-Pavord, H. R.; Bone, P. A.; Ander, E. L.; Young, S. D.

    2015-01-01

    With the release of the Department for the Environment, Food and Rural Affairs/Advisory Committee on Animal Feed Guidance Note for Supplementing Copper to Bovines it was noted that the current copper status of the national herd was not known. Liver samples were recovered from 510 cull cattle at a single abattoir across a period of three days. The samples were wet-ashed and liver copper concentrations determined by inductively coupled plasma mass spectrometry analysis. Breed, age and previous location information were obtained from the British Cattle Movement Service. Dairy breeds had higher liver copper concentrations than beef breeds. Holstein-Friesian and ‘other’ dairy breeds had 38.3 per cent and 40 per cent of cattle above the Animal Health and Veterinary Laboratories Agency (AHVLA) reference range (8000 µmol/kg dry matter), respectively, whereas only 16.9 per cent of animals in the combined beef breeds exceeded this value. It was found that underlying topsoil copper concentration was not related to liver copper content and that age of the animal also had little effect on liver concentration. In conclusion, over 50 per cent of the liver samples tested had greater-than-normal concentrations of copper with almost 40 per cent of the female dairy cattle having liver copper concentrations above the AHVLA reference range, indicating that a significant proportion of the UK herd is at risk of chronic copper toxicity. PMID:26489996

  14. Effect of fission neutron irradiation on the tensile and electrical properties of copper and copper alloys

    SciTech Connect

    Fabritsiev, S.A.; Zinkle, S.J.; Rowcliffe, A.F.

    1995-04-01

    The objective of this study is to evaluate the properties of several copper alloys following fission reactor irradiation at ITER-relevant temperatures of 80 to 200{degrees}C. This study provides some of the data needed for the ITER research and development Task T213. These low temperature irradiations caused significant radiation hardening and a dramatic decrease in the work hardening ability of copper and copper alloys. The uniform elongation was higher at 200{degree}C compared to 100{degree}C, but still remained below 1% for most of the copper alloys.

  15. Molecular imaging and therapy targeting copper metabolism in hepatocellular carcinoma.

    PubMed

    Wachsmann, Jason; Peng, Fangyu

    2016-01-07

    Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide. Significant efforts have been devoted to identify new biomarkers for molecular imaging and targeted therapy of HCC. Copper is a nutritional metal required for the function of numerous enzymatic molecules in the metabolic pathways of human cells. Emerging evidence suggests that copper plays a role in cell proliferation and angiogenesis. Increased accumulation of copper ions was detected in tissue samples of HCC and many other cancers in humans. Altered copper metabolism is a new biomarker for molecular cancer imaging with position emission tomography (PET) using radioactive copper as a tracer. It has been reported that extrahepatic mouse hepatoma or HCC xenografts can be localized with PET using copper-64 chloride as a tracer, suggesting that copper metabolism is a new biomarker for the detection of HCC metastasis in areas of low physiological copper uptake. In addition to copper modulation therapy with copper chelators, short-interference RNA specific for human copper transporter 1 (hCtr1) may be used to suppress growth of HCC by blocking increased copper uptake mediated by hCtr1. Furthermore, altered copper metabolism is a promising target for radionuclide therapy of HCC using therapeutic copper radionuclides. Copper metabolism has potential as a new theranostic biomarker for molecular imaging as well as targeted therapy of HCC.

  16. Molecular imaging and therapy targeting copper metabolism in hepatocellular carcinoma

    PubMed Central

    Wachsmann, Jason; Peng, Fangyu

    2016-01-01

    Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide. Significant efforts have been devoted to identify new biomarkers for molecular imaging and targeted therapy of HCC. Copper is a nutritional metal required for the function of numerous enzymatic molecules in the metabolic pathways of human cells. Emerging evidence suggests that copper plays a role in cell proliferation and angiogenesis. Increased accumulation of copper ions was detected in tissue samples of HCC and many other cancers in humans. Altered copper metabolism is a new biomarker for molecular cancer imaging with position emission tomography (PET) using radioactive copper as a tracer. It has been reported that extrahepatic mouse hepatoma or HCC xenografts can be localized with PET using copper-64 chloride as a tracer, suggesting that copper metabolism is a new biomarker for the detection of HCC metastasis in areas of low physiological copper uptake. In addition to copper modulation therapy with copper chelators, short-interference RNA specific for human copper transporter 1 (hCtr1) may be used to suppress growth of HCC by blocking increased copper uptake mediated by hCtr1. Furthermore, altered copper metabolism is a promising target for radionuclide therapy of HCC using therapeutic copper radionuclides. Copper metabolism has potential as a new theranostic biomarker for molecular imaging as well as targeted therapy of HCC. PMID:26755872

  17. Lead and Copper Rule Revisions White Paper

    EPA Pesticide Factsheets

    The Lead and Copper Rule (LCR) Revisions White Paper provides examples of regulatory options to improve the existing rule. The paper highlights key challenges, opportunities, and analytical issues presented by these options.

  18. Bioaccumulation of copper by Trichoderma viride.

    PubMed

    Anand, Purnima; Isar, Jasmine; Saran, Saurabh; Saxena, Rajendra Kumar

    2006-05-01

    Studies were carried out on interaction of Trichoderma viride with copper and reports bioaccumulation as a mechanism of copper tolerance during growth. There was a marked increase in the lag phase of the growth, which was concentration dependent. At a concentration of 100 mg/L of CuCl2.2H2O, 81% of Cu(II) were removed by 3.4 g/L of the biomass in 72 h. The process was temperature and pH dependent. The maximum copper bioaccumulation occurred at 30 degrees C, pH 5.0. Metabolic inhibitors such as sodium azide (NaN3) and 2,4-dinitrophenol (2,4-DNP) drastically reduced the extent of Cu(II) bioaccumulation. Electron microscopy and cell fractionation studies revealed that 70-80% of copper was present as a layer on the cell wall surface.

  19. Electroless Copper Deposition: A Sustainable Approach

    NASA Astrophysics Data System (ADS)

    Kutnahorsky, Marika Renee

    A sustainable electroless copper coating process was developed for plating automotive fasteners shaped from AISI 9255 low carbon, high silicon steel. The objective was to minimize the ionic and organic species present in each step of the plating process. A sulfuric acid solution inhibited with quinine was defined to clean the steel prior to plating. The corrosivity of the solution was examined through electrochemical and weight loss measurements to evaluate the efficiency of the cleaning process at high temperatures and high acid concentrations. An electroless copper coating process was then developed using a simple copper sulfate chemistry inhibited with quinine to extend the possible operating window. Finally, benzotriazole was evaluated as a possible anti-oxidant coating. Accelerated thioacetamide corrosion tests were used to evaluate the corrosion inhibition of benzotriazole on copper coatings.

  20. Thermal Conductances of Pressed Copper Contacts

    NASA Technical Reports Server (NTRS)

    Salerno, L.; Kittel, P.; Spivak, A.

    1986-01-01

    Report describes investigation of thermal conductivities of smooth copper contacts pressed together at liquid-helium temperatures. Investigation prompted by need for accurate thermal models for infrared detectors and other cryogenic instruments.

  1. 21 CFR 524.463 - Copper naphthenate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... and ponies for thrush caused by organisms susceptible to copper naphthenate. (3) Limitations. Use on horses and ponies only. Avoid contact around eyes. Do not contaminate feed. Do not use in horses...

  2. Diamine Ligands in Copper-Catalyzed Reactions

    PubMed Central

    Surry, David S.

    2012-01-01

    The utility of copper-mediated cross-coupling reactions has been significantly increased by the development of mild reaction conditions and the ability to employ catalytic amounts of copper. The use of diamine-based ligands has been important in these advances and in this review we discuss these systems, including the choice of reaction conditions and applications in the synthesis of pharmaceuticals, natural products and designed materials. PMID:22384310

  3. Copper mercaptides as sulfur dioxide indicators

    DOEpatents

    Eller, Phillip G.; Kubas, Gregory J.

    1979-01-01

    Organophosphine copper(I) mercaptide complexes are useful as convenient and semiquantitative visual sulfur dioxide gas indicators. The air-stable complexes form 1:1 adducts in the presence of low concentrations of sulfur dioxide gas, with an associated color change from nearly colorless to yellow-orange. The mercaptides are made by mixing stoichiometric amounts of the appropriate copper(I) mercaptide and phosphine in an inert organic solvent.

  4. The Influence of Copper on Steel

    DTIC Science & Technology

    1917-02-07

    quenching in oil instead of water. He con- cludes that the presence of copper need not cause apprehension, although tere may not be any advantage in its...present work of .r. Breuil, to be h- zein de- scribed, re 2 resents on; of the most extended investigations on the zffect of copper on the properties...Clevenger and Ray, which will now be described. Experimantal. MAKING INGOTS. 𔄂mall, circular, oil fired fuinace used, (using IoA pressure burner), to heat

  5. NMR in Copper-Oxide Metals

    SciTech Connect

    Varma, C.M.

    1996-10-01

    The anomalous part of the NMR relaxation rate of copper nuclei in the normal state of copper-oxide metals is calculated using the orbital magnetic parts of the fluctuations derived in a recent theory to explain the long wavelength transport anomalies. Oxygen and yttrium reside on lattice sites at which the anomalous contribution is absent at all hole densities. The frequency, momentum dependence, and the form factor of the fluctuations is predicted. {copyright} {ital 1996 The American Physical Society.}

  6. Recovering selenium from copper refinery slimes

    NASA Astrophysics Data System (ADS)

    Hyvärinen, Olli; Lindroos, Leo; Yllö, Erkki

    1989-07-01

    The selenium contained within copper refinery slimes may be recovered advantageously by roasting at about 600°C. While roasting in air is inefficient, roasting in a sulfating atmosphere enables practically complete selenium recovery. Based on laboratory tests, a new selenium recovery process was adopted at Outokumpu Copper Refinery. In this process, sulfation is achieved by feeding sulfur dioxide and oxygen into the roasting furnace.

  7. Forming Refractory Insulation On Copper Wire

    NASA Technical Reports Server (NTRS)

    Setlock, J.; Roberts, G.

    1995-01-01

    Alternative insulating process forms flexible coat of uncured refractory insulating material on copper wire. Coated wire formed into coil or other complex shape. Wire-coating apparatus forms "green" coat on copper wire. After wire coiled, heating converts "green" coat to refractory electrical insulator. When cured to final brittle form, insulating material withstands temperatures above melting temperature of wire. Process used to make coils for motors, solenoids, and other electrical devices to be operated at high temperatures.

  8. Copper staves in the blast furnace

    SciTech Connect

    Helenbrook, R.G.; Kowalski, W.; Grosspietsch, K.H.; Hille, H.

    1996-08-01

    Operational data for stave cooling systems for two German blast furnaces show good correlation with predicted thermal results. Copper staves have been installed in blast furnaces in the zones exposed to the highest thermal loads. The good operational results achieved confirm the choice of copper staves in the areas of maximum heat load. Both temperature measurements and predictions establish that the MAN GHH copper staves do not experience large temperature fluctuations and that the hot face temperatures will be below 250 F. This suggests that the copper staves maintain a more stable accretion layer than the cast iron staves. Contrary to initial expectations, heat flux to the copper staves is 50% lower than that to cast iron staves. The more stable accretion layer acts as an excellent insulator for the stave and greatly reduces the number of times the hot face of the stave is exposed to the blast furnace process and should result in a more stable furnace operation. In the future, it may be unnecessary to use high quality, expensive refractories in front of copper staves because of the highly stable accretion layer that appears to rapidly form due to the lower operating temperature of the staves. There is a balance of application regions for cast iron and copper staves that minimizes the capital cost of a blast furnace reline and provides an integrated cooling system with multiple campaign life potential. Cast iron staves are proven cooling elements that are capable of multiple campaign life in areas of the blast furnace which do not experience extreme heat loads. Copper staves are proving to be an effective and reliable blast furnace cooling element that are subject to virtually no wear and are projected to have a longer campaign service life in the areas of highest thermal load in the blast furnace.

  9. Regulation of copper transporter 2 expression by copper and cisplatin in human ovarian carcinoma cells.

    PubMed

    Blair, Brian G; Larson, Christopher A; Adams, Preston L; Abada, Paolo B; Safaei, Roohangiz; Howell, Stephen B

    2010-06-01

    Down-regulation of copper transporter 1 (CTR1) reduces uptake and sensitivity, whereas down-regulation of CTR2 enhances both. Cisplatin (DDP) triggers the rapid degradation of CTR1 and thus limits its own accumulation. We sought to determine the effect of DDP and copper on the expression of CTR2. Changes in CTR1 and CTR2 mRNA and protein levels in human ovarian carcinoma 2008 cells and ATOX1(+/+) and ATOX1(-/-) mouse embryo fibroblasts in response to exposure to DDP and copper were measured by quantitative reverse transcriptase-polymerase chain reaction, Western blot analysis, and deconvolution microscopy. DDP triggered rapid degradation of CTR1 in 2008 human ovarian cancer cells. However, it increased the expression of CTR2 mRNA and protein levels. Expression of CTR2 was heavily modulated by changes in intracellular copper concentration; copper depletion produced rapid disappearance of CTR2, whereas excess copper increased the level of CTR2 protein. This increase was associated with an increase in CTR2 mRNA and prolongation of the CTR2 half-life. Consistent with prior observations that short hairpin RNA interference-mediated knockdown of CTR2 enhanced DDP uptake and tumor cell kill, reduction of CTR2 by copper starvation also enhanced DDP uptake and cytotoxicity. Comparison of the ability of copper and DDP to modulate the expression of CTR1 in ATOX1(+/+) and ATOX1(-/-) indicated that ATOX1 participates in the regulation of CTR2 expression. Unlike CTR1, the expression of CTR2 is increased rather than decreased by DDP. Therefore, these two copper transporters have opposite effects on DDP sensitivity. CTR2 expression is regulated by copper availability via the copper-dependent regulator ATOX1.

  10. Regulation of Copper Transporter 2 Expression by Copper and Cisplatin in Human Ovarian Carcinoma Cells

    PubMed Central

    Blair, Brian G.; Larson, Christopher A.; Adams, Preston L.; Abada, Paolo B.; Safaei, Roohangiz

    2010-01-01

    Down-regulation of copper transporter 1 (CTR1) reduces uptake and sensitivity, whereas down-regulation of CTR2 enhances both. Cisplatin (DDP) triggers the rapid degradation of CTR1 and thus limits its own accumulation. We sought to determine the effect of DDP and copper on the expression of CTR2. Changes in CTR1 and CTR2 mRNA and protein levels in human ovarian carcinoma 2008 cells and ATOX1(+/+) and ATOX1(−/−) mouse embryo fibroblasts in response to exposure to DDP and copper were measured by quantitative reverse transcriptase-polymerase chain reaction, Western blot analysis, and deconvolution microscopy. DDP triggered rapid degradation of CTR1 in 2008 human ovarian cancer cells. However, it increased the expression of CTR2 mRNA and protein levels. Expression of CTR2 was heavily modulated by changes in intracellular copper concentration; copper depletion produced rapid disappearance of CTR2, whereas excess copper increased the level of CTR2 protein. This increase was associated with an increase in CTR2 mRNA and prolongation of the CTR2 half-life. Consistent with prior observations that short hairpin RNA interference-mediated knockdown of CTR2 enhanced DDP uptake and tumor cell kill, reduction of CTR2 by copper starvation also enhanced DDP uptake and cytotoxicity. Comparison of the ability of copper and DDP to modulate the expression of CTR1 in ATOX1(+/+) and ATOX1(−/−) indicated that ATOX1 participates in the regulation of CTR2 expression. Unlike CTR1, the expression of CTR2 is increased rather than decreased by DDP. Therefore, these two copper transporters have opposite effects on DDP sensitivity. CTR2 expression is regulated by copper availability via the copper-dependent regulator ATOX1. PMID:20194531

  11. Copper stable isotopes to trace copper behavior in wetland systems.

    PubMed

    Babcsányi, Izabella; Imfeld, Gwenaël; Granet, Mathieu; Chabaux, François

    2014-05-20

    Wetlands are reactive zones of the landscape that can sequester metals released by industrial and agricultural activities. Copper (Cu) stable isotope ratios (δ(65)Cu) have recently been used as tracers of transport and transformation processes in polluted environments. Here, we used Cu stable isotopes to trace the behavior of Cu in a stormwater wetland receiving runoff from a vineyard catchment (Alsace, France). The Cu loads and stable isotope ratios were determined in the dissolved phase, suspended particulate matter (SPM), wetland sediments, and vegetation. The wetland retained >68% of the dissolved Cu and >92% of the SPM-bound Cu, which represented 84.4% of the total Cu in the runoff. The dissolved Cu became depleted in (65)Cu when passing through the wetland (Δ(65)Cuinlet-outlet from 0.03‰ to 0.77‰), which reflects Cu adsorption to aluminum minerals and organic matter. The δ(65)Cu values varied little in the wetland sediments (0.04 ± 0.10‰), which stored >96% of the total Cu mass within the wetland. During high-flow conditions, the Cu flowing out of the wetland became isotopically lighter, indicating the mobilization of reduced Cu(I) species from the sediments and Cu reduction within the sediments. Our results demonstrate that the Cu stable isotope ratios may help trace Cu behavior in redox-dynamic environments such as wetlands.

  12. Method for providing uranium with a protective copper coating

    DOEpatents

    Waldrop, Forrest B.; Jones, Edward

    1981-01-01

    The present invention is directed to a method for providing uranium metal with a protective coating of copper. Uranium metal is subjected to a conventional cleaning operation wherein oxides and other surface contaminants are removed, followed by etching and pickling operations. The copper coating is provided by first electrodepositing a thin and relatively porous flash layer of copper on the uranium in a copper cyanide bath. The resulting copper-layered article is then heated in an air or inert atmosphere to volatilize and drive off the volatile material underlying the copper flash layer. After the heating step an adherent and essentially non-porous layer of copper is electro-deposited on the flash layer of copper to provide an adherent, multi-layer copper coating which is essentially impervious to corrosion by most gases.

  13. Copper modulates the degradation of copper chaperone for Cu,Zn superoxide dismutase by the 26 S proteosome.

    PubMed

    Bertinato, Jesse; L'Abbé, Mary R

    2003-09-12

    Copper chaperones are copper-binding proteins that directly insert copper into specific targets, preventing the accumulation of free copper ions that can be toxic to the cell. Despite considerable advances in the understanding of copper transfer from copper chaperones to their target, to date, there is no information regarding how the activity of these proteins is regulated in higher eukaryotes. The insertion of copper into the antioxidant enzyme Cu,Zn superoxide dismutase (SOD1) depends on the copper chaperone for SOD1 (CCS). We have recently reported that CCS protein is increased in tissues of rats fed copper-deficient diets suggesting that copper may regulate CCS expression. Here we show that whereas copper deficiency increased CCS protein in rats, mRNA level was unaffected. Rodent and human cell lines cultured in the presence of the specific copper chelator 2,3,2-tetraamine displayed a dose-dependent increase in CCS protein that could be reversed with the addition of copper but not iron or zinc to the cells. Switching cells from copper-deficient to copper-rich medium promoted the rapid degradation of CCS, which could be blocked by the proteosome inhibitors MG132 and lactacystin but not a cysteine protease inhibitor or inhibitors of the lysosomal degradation pathway. In addition, CCS degradation was slower in copper-deficient cells than in cells cultured in copper-rich medium. Together, these data show that copper regulates CCS expression by modulating its degradation by the 26 S proteosome and suggest a novel role for CCS in prioritizing the utilization of copper when it is scarce.

  14. The Intestinal Copper Exporter CUA-1 Is Required for Systemic Copper Homeostasis in Caenorhabditis elegans*♦

    PubMed Central

    Chun, Haarin; Sharma, Anuj Kumar; Lee, Jaekwon; Chan, Jefferson; Jia, Shang; Kim, Byung-Eun

    2017-01-01

    Copper plays key catalytic and regulatory roles in biochemical processes essential for normal growth, development, and health. Defects in copper metabolism cause Menkes and Wilson's disease, myeloneuropathy, and cardiovascular disease and are associated with other pathophysiological states. Consequently, it is critical to understand the mechanisms by which organisms control the acquisition, distribution, and utilization of copper. The intestinal enterocyte is a key regulatory point for copper absorption into the body; however, the mechanisms by which intestinal cells transport copper to maintain organismal copper homeostasis are poorly understood. Here, we identify a mechanism by which organismal copper homeostasis is maintained by intestinal copper exporter trafficking that is coordinated with extraintestinal copper levels in Caenorhabditis elegans. Specifically, we show that CUA-1, the C. elegans homolog of ATP7A/B, localizes to lysosome-like organelles (gut granules) in the intestine under copper overload conditions for copper detoxification, whereas copper deficiency results in a redistribution of CUA-1 to basolateral membranes for copper efflux to peripheral tissues. Worms defective in gut granule biogenesis exhibit defects in copper sequestration and increased susceptibility to toxic copper levels. Interestingly, however, a splice isoform CUA-1.2 that lacks a portion of the N-terminal domain is targeted constitutively to the basolateral membrane irrespective of dietary copper concentration. Our studies establish that CUA-1 is a key intestinal copper exporter and that its trafficking is regulated to maintain systemic copper homeostasis. C. elegans could therefore be exploited as a whole-animal model system to study regulation of intra- and intercellular copper trafficking pathways. PMID:27881675

  15. Estimating Dermal Transfer of Copper Particles from the ...

    EPA Pesticide Factsheets

    Lumber pressure-treated with micronized copper was examined for the release of copper and copper micro/nanoparticles using a surface wipe method to simulate dermal transfer. In 2003, the wood industry began replacing CCA treated lumber products for residential use with copper based formulations. Micronized copper (nano to micron sized particles) has become the preferred treatment formulation. There is a lack of information on the release of copper, the fate of the particles during dermal contact, and the copper exposure level to children from hand-to-mouth transfer. For the current study, three treated lumber products, two micronized copper and one ionic copper, were purchased from commercial retailers. The boards were left to weather outdoors for approximately 1 year. Over the year time period, hand wipe samples were collected periodically to determine copper transfer from the wood surfaces. The two micronized formulations and the ionic formulation released similar levels of total copper. The amount of copper released was high initially, but decreased to a constant level (~1.5 mg m-2) after the first month of outdoor exposure. Copper particles were identified on the sampling cloths during the first two months of the experiment, after which the levels of copper were insufficient to collect interpretable data. After 1 month, the particles exhibited minimal changes in shape and size. At the end of 2-months, significant deterioration of the particles was

  16. Copper redistribution in murine macrophages in response to Salmonella infection.

    PubMed

    Achard, Maud E S; Stafford, Sian L; Bokil, Nilesh J; Chartres, Jy; Bernhardt, Paul V; Schembri, Mark A; Sweet, Matthew J; McEwan, Alastair G

    2012-05-15

    The movement of key transition metal ions is recognized to be of critical importance in the interaction between macrophages and intracellular pathogens. The present study investigated the role of copper in mouse macrophage responses to Salmonella enterica sv. Typhimurium. The copper chelator BCS (bathocuproinedisulfonic acid, disodium salt) increased intracellular survival of S. Typhimurium within primary mouse BMM (bone-marrow-derived macrophages) at 24 h post-infection, implying that copper contributed to effective host defence against this pathogen. Infection of BMM with S. Typhimurium or treatment with the TLR (Toll-like receptor) 4 ligand LPS (lipopolysaccharide) induced the expression of several genes encoding proteins involved in copper transport [Ctr (copper transporter) 1, Ctr2 and Atp7a (copper-transporting ATPase 1)], as well as the multi-copper oxidase Cp (caeruloplasmin). Both LPS and infection with S. Typhimurium triggered copper accumulation within punctate intracellular vesicles (copper 'hot spots') in BMM as indicated by the fluorescent reporter CS1 (copper sensor 1). These copper hot spots peaked in their accumulation at approximately 18 h post-stimulation and were dependent on copper uptake into cells. Localization studies indicated that the copper hot spots were in discrete vesicles distinct from Salmonella containing vacuoles and lysosomes. We propose that copper hot spot formation contributes to antimicrobial responses against professional intracellular bacterial pathogens.

  17. Copper Recycling in the United States in 2004

    USGS Publications Warehouse

    Goonan, Thomas G.

    2009-01-01

    As one of a series of reports that describe the recycling of metal commodities in the United States, this report discusses the flow of copper from production through distribution and use, with particular emphasis on the recycling of industrial scrap (new scrap1) and used products (old scrap) in the year 2004. This materials flow study includes a description of copper supply and demand for the United States to illustrate the extent of copper recycling and to identify recycling trends. Understanding how materials flow from a source through disposition can aid in improving the management of natural resource delivery systems. In 2004, the U.S. refined copper supply was 2.53 million metric tons (Mt) of refined unalloyed copper. With adjustment for refined copper exports of 127,000 metric tons (t) of copper, the net U.S. refined copper supply was 2.14 Mt of copper. With this net supply and a consumer inventory decrease of 9,000 t of refined copper, 2.42 Mt of refined copper was consumed by U.S. semifabricators (brass mills, wire rod mills, ingot makers, and foundries and others) in 2004. In addition to the 2.42 Mt of refined copper consumed in 2004, U.S. copper semifabricators consumed 853,000 t of copper contained in recycled scrap. Furthermore, 61,000 t of copper contained in scrap was consumed by noncopper alloy makers, for example, steelmakers and aluminum alloy makers. Old scrap recycling efficiency for copper was estimated to be 43 percent of theoretical old scrap supply, the recycling rate for copper was 30 percent of apparent supply, and the new-scrap-to-old-scrap ratio for U.S. copper product production was 3.2 (76:24).

  18. A role for copper in protozoan grazing - two billion years selecting for bacterial copper resistance.

    PubMed

    Hao, Xiuli; Lüthje, Freja; Rønn, Regin; German, Nadezhda A; Li, Xuanji; Huang, Fuyi; Kisaka, Javan; Huffman, David; Alwathnani, Hend A; Zhu, Yong-Guan; Rensing, Christopher

    2016-11-01

    The Great Oxidation Event resulted in integration of soft metals in a wide range of biochemical processes including, in our opinion, killing of bacteria by protozoa. Compared to pressure from anthropologic copper contamination, little is known on impacts of protozoan predation on maintenance of copper resistance determinants in bacteria. To evaluate the role of copper and other soft metals in predatory mechanisms of protozoa, we examined survival of bacteria mutated in different transition metal efflux or uptake systems in the social amoeba Dictyostelium discoideum. Our data demonstrated a strong correlation between the presence of copper/zinc efflux as well as iron/manganese uptake, and bacterial survival in amoebae. The growth of protozoa, in turn, was dependent on bacterial copper sensitivity. The phagocytosis of bacteria induced upregulation of Dictyostelium genes encoding the copper uptake transporter p80 and a triad of Cu(I)-translocating PIB -type ATPases. Accumulated Cu(I) in Dictyostelium was monitored using a copper biosensor bacterial strain. Altogether, our data demonstrate that Cu(I) is ultimately involved in protozoan predation of bacteria, supporting our hypothesis that protozoan grazing selected for the presence of copper resistance determinants for about two billion years.

  19. Impact of copper ligand mutations on a cupredoxin with a green copper center.

    PubMed

    Roger, Magali; Sciara, Giuliano; Biaso, Frédéric; Lojou, Elisabeth; Wang, Xie; Bauzan, Marielle; Giudici-Orticoni, Marie-Thérèse; Vila, Alejandro J; Ilbert, Marianne

    2017-02-16

    Mononuclear cupredoxins contain a type 1 copper center with a trigonal or tetragonal geometry usually maintained by four ligands, a cystein, two histidines and a methionine. The recent discovery of new members of this family with unusual properties demonstrates, however, the versatility of this class of proteins. Changes in their ligand set lead to drastic variation in their metal site geometry and in the resulting spectroscopic and redox features. In our work, we report the identification of the copper ligands in the recently discovered cupredoxin AcoP. We show that even though AcoP possesses a classical copper ligand set, it has a highly perturbed copper center. In depth studies of mutant's properties suggest a high degree of constraint existing in the copper center of the wild type protein and even the addition of exogenous ligands does not lead to the reconstitution of the initial copper center. Not only the chemical nature of the axial ligand but also constraints brought by its covalent binding to the protein backbone might be critical to maintain a green copper site with high redox potential. This work illustrates the importance of experimentally dissecting the molecular diversity of cupredoxins to determine the molecular determinants responsible for their copper center geometry and redox potential.

  20. Sulfidation treatment of copper-containing plating sludge towards copper resource recovery.

    PubMed

    Kuchar, D; Fukuta, T; Onyango, M S; Matsuda, H

    2006-11-02

    The present study is concerned with the sulfidation treatment of copper-containing plating sludge towards copper resource recovery by flotation of copper sulfide from treated sludge. The sulfidation treatment was carried out by contacting simulated or real copper plating sludge with Na(2)S solution for a period of 5 min to 24 h. The initial molar ratio of S(2-) to Cu(2+) (S(2-) to Me(2+) in the case of real sludge) was adjusted to 1.00, 1.25 or 1.50, while the solid to liquid ratio was set at 1:50. As a result, it was found that copper compounds were converted to various copper sulfides within the first 5 min. In the case of simulated copper sludge, CuS was identified as the main sulfidation product at the molar ratio of S(2-) to Cu(2+) of 1.00, while Cu(7)S(4) (Roxbyite) was mainly found at the molar ratios of S(2-) to Cu(2+) of 1.50 and 1.25. Based on the measurements of oxidation-reduction potential, the formation of either CuS or Cu(7)S(4) at different S(2-) to Cu(2+) molar ratios was attributed to the changes in the oxidation-reduction potential. By contrast, in the case of sulfidation treatment of real copper sludge, CuS was predominantly formed, irrespective of S(2-) to Me(2+) molar ratio.

  1. Copper intake and health threat by consuming seafood from copper-contaminated coastal environments in Taiwan

    SciTech Connect

    Han, B.C. . School of Public Health); Jeng, W.L.; Hung, T.C. . Inst. of Oceanography); Jeng, M.S. . Inst. of Zoology)

    1994-05-01

    The purpose of this paper is to describe the impact of copper pollution on the main aquaculture coast of Taiwan and the potential risk from eating the green oysters cultured along the polluted coast. The data show that the highest average concentration of copper in oysters was observed in the Erhjin Chi estuary from 1986 to 1990. The copper concentration in both the seawater and the sediment collected along the Erhjin Chi estuary was also the highest in all sampling locations. Copper concentration in oysters collected from Erhjin Chi, Hsiangshan, and Anping from 1988 to 1990 was, respectively, 61, 29, and 22 times higher than that of 10 years ago. The potential frisk from consuming oysters is relatively higher than that of other seafoods due the high bioaccumulation of oysters. The oysters in the Erhjin Chi estuary had an average concentration of copper of 3,075 [+-] 826 [mu]g/g during the past three years (1988--1990). The average copper intake from oysters for an adult with 70 kg body weight was 12.6 mg/d. The estimate indicated that the average copper intake from the oysters for female individuals is 14 times more than that of international limits. Based on the average value, long-term intake of copper through consumption of oysters cultured along the Erhjin Chi estuary be critical, especially for some high-risk groups.

  2. Putting copper into action: copper-impregnated products with potent biocidal activities.

    PubMed

    Borkow, Gadi; Gabbay, Jeffrey

    2004-11-01

    Copper ions, either alone or in copper complexes, have been used for centuries to disinfect liquids, solids, and human tissue. Today copper is used as a water purifier, algaecide, fungicide, nematocide, molluscicide, and antibacterial and antifouling agent. Copper also displays potent antiviral activity. We hypothesized that introducing copper into clothing, bedding, and other articles would provide them with biocidal properties. A durable platform technology has been developed that introduces copper into cotton fibers, latex, and other polymeric materials. This study demonstrates the broad-spectrum antimicrobial (antibacterial, antiviral, antifungal) and antimite activities of copper-impregnated fibers and polyester products. This technology enabled the production of antiviral gloves and filters (which deactivate HIV-1 and other viruses), antibacterial self-sterilizing fabrics (which kill antibiotic-resistant bacteria, including methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococci), antifungal socks (which alleviate symptoms of athlete's foot), and anti-dust mite mattress covers (which reduce mite-related allergies). These products did not have skin-sensitizing properties, as determined by guine pig maximization and rabbit skin irritation tests. Our study demonstrates the potential use of copper in new applications. These applications address medical issues of the greatest importance, such as viral transmissions; nosocomial, or healthcare-associated, infections; and the spread of antibiotic-resistant bacteria.

  3. Speciation and leachability of copper in mine tailings from porphyry copper mining: influence of particle size.

    PubMed

    Hansen, Henrik K; Yianatos, Juan B; Ottosen, Lisbeth M

    2005-09-01

    Mine tailing from the El Teniente-Codelco copper mine situated in VI Region of Chile was analysed in order to evaluate the mobility and speciation of copper in the solid material. Mine tailing was sampled after the rougher flotation circuits, and the copper content was measured to 1150 mg kg (-1) dry matter. This tailing was segmented into fractions of different size intervals: 0-38, 38-45, 45-53, 53-75, 75-106, 106-150, 150-212, and >212 microm, respectively. Copper content determination, sequential chemical extraction, and desorption experiments were carried out for each size interval in order to evaluate the speciation of copper. It was found that the particles of smallest size contained 50-60% weak acid leachable copper, whereas only 32% of the copper found in largest particles could be leached in weak acid. Copper oxides and carbonates were the dominating species in the smaller particles, and the larger particles contained considerable amounts of sulphides.

  4. Abrasive Wear Behaviour of COPPER-SiC and COPPER-SiO2 Composites

    NASA Astrophysics Data System (ADS)

    Umale, Tejas; Singh, Amarjit; Reddy, Y.; Khatitrkar, R. K.; Sapate, S. G.

    The present paper reports abrasive wear behaviour of copper matrix composites reinforced with silicon carbide and silica particles. Copper - SiC (12%) and Copper-SiO2 (9%) composites were prepared by powder metallurgical technique. Metallography, image analysis and hardness studies were carried out on copper composites. The abrasive wear experiments were carried out using pin on disc apparatus. The effect of sliding distance and load was studied on Copper - SiC (12%) and Copper-SiO2 (9%) composites. The abrasive wear volume loss increased with sliding distance in both the composites although the magnitude of increase was different in each case. Copper - SiC (12%) composites exhibited relatively better abrasion resistance as compared to and Copper-SiO2 (9%) composites. The abraded surfaces were observed under scanning electron microscope to study the morphology of abraded surfaces and operating wear mechanism. The analysis of wear debris particles was also carried out to substantiate the findings of the investigation.

  5. Non-enzymic copper reduction by menaquinone enhances copper toxicity in Lactococcus lactis IL1403.

    PubMed

    Abicht, Helge K; Gonskikh, Yulia; Gerber, Simon D; Solioz, Marc

    2013-06-01

    Lactococcus lactis possesses a pronounced extracellular Cu(2+)-reduction activity which leads to the accumulation of Cu(+) in the medium. The kinetics of this reaction were not saturable by increasing copper concentrations, suggesting a non-enzymic reaction. A copper-reductase-deficient mutant, isolated by random transposon mutagenesis, had an insertion in the menE gene, which encodes O-succinylbenzoic acid CoA ligase. This is a key enzyme in menaquinone biosynthesis. The ΔmenE mutant was deficient in short-chain menaquinones, and exogenously added menaquinone complemented the copper-reductase-deficient phenotype. Haem-induced respiration of wild-type L. lactis efficiently suppressed copper reduction, presumably by competition by the bd-type quinol oxidase for menaquinone. As expected, the ΔmenE mutant was respiration-deficient, but could be made respiration-proficient by supplementation with menaquinone. Growth of wild-type cells was more copper-sensitive than that of the ΔmenE mutant, due to the production of Cu(+) ions by the wild-type. This growth inhibition of the wild-type was strongly attenuated if Cu(+) was scavenged with the Cu(I) chelator bicinchoninic acid. These findings support a model whereby copper is non-enzymically reduced at the membrane by menaquinones. Respiration effectively competes for reduced quinones, which suppresses copper reduction. These findings highlight novel links between copper reduction, respiration and Cu(+) toxicity in L. lactis.

  6. The Amyloid Precursor Protein of Alzheimer's Disease in the Reduction of Copper(II) to Copper(I)

    NASA Astrophysics Data System (ADS)

    Multhaup, Gerd; Schlicksupp, Andrea; Hesse, Lars; Beher, Dirk; Ruppert, Thomas; Masters, Colin L.; Beyreuther, Konrad

    1996-03-01

    The transition metal ion copper(II) has a critical role in chronic neurologic diseases. The amyloid precursor protein (APP) of Alzheimer's disease or a synthetic peptide representing its copper-binding site reduced bound copper(II) to copper(I). This copper ion-mediated redox reaction led to disulfide bond formation in APP, which indicated that free sulfhydryl groups of APP were involved. Neither superoxide nor hydrogen peroxide had an effect on the kinetics of copper(II) reduction. The reduction of copper(II) to copper(I) by APP involves an electron-transfer reaction and could enhance the production of hydroxyl radicals, which could then attack nearby sites. Thus, copper-mediated toxicity may contribute to neurodegeneration in Alzheimer's disease.

  7. Copper-2 Ingestion, Plus Increased Meat Eating Leading to Increased Copper Absorption, Are Major Factors Behind the Current Epidemic of Alzheimer's Disease.

    PubMed

    Brewer, George J

    2015-12-02

    It has become clear that copper toxicity is playing a major role in Alzheimer's disease; but why is the brain copper toxicity with cognition loss in Alzheimer's disease so much different clinically than brain copper toxicity in Wilson's disease, which results in a movement disorder? Furthermore, why is the inorganic copper of supplement pills and in drinking water so much more damaging to cognition than the organic copper in food? A recent paper, which shows that almost all food copper is copper-1, that is the copper-2 of foods reverts to the reduced copper-1 form at death or harvest, gives new insight into these questions. The body has an intestinal transport system for copper-1, Ctr1, which channels copper-1 through the liver and into safe channels. Ctr1 cannot absorb copper-2, and some copper-2 bypasses the liver, ends up in the blood quickly, and is toxic to cognition. Humans evolved to handle copper-1 safely, but not copper-2. Alzheimer's is at least in part, a copper-2 toxicity disease, while Wilson's is a general copper overload disease. In this review, we will show that the epidemiology of the Alzheimer's epidemic occurring in developed, but not undeveloped countries, fits with the epidemiology of exposure to copper-2 ingestion leached from copper plumbing and from copper supplement pill ingestion. Increased meat eating in developed countries is also a factor, because it increases copper absorption, and thus over all copper exposure.

  8. Potential phytoextraction and phytostabilization of perennial peanut on copper-contaminated vineyard soils and copper mining waste.

    PubMed

    Andreazza, Robson; Bortolon, Leandro; Pieniz, Simone; Giacometti, Marcelo; Roehrs, Dione D; Lambais, Mácio R; Camargo, Flávio A O

    2011-12-01

    This study sought to evaluate the potential of perennial peanut (Arachis pintoi) for copper phytoremediation in vineyard soils (Inceptisol and Mollisol) contaminated with copper and copper mining waste. Our results showed high phytomass production of perennial peanut in both vineyard soils. Macronutrient uptakes were not negatively affected by perennial peanut cultivated in all contaminated soils. Plants cultivated in Mollisol showed high copper concentrations in the roots and shoots of 475 and 52 mg kg(-1), respectively. Perennial peanut plants showed low translocation factor values for Cu, although these plants showed high bioaccumulation factor (BCF) for both vineyard soils, Inceptisol and Mollisol, with BCF values of 3.83 and 3.24, respectively, being characterized as a copper hyperaccumulator plant in these soils. Copper phytoextraction from Inceptisol soil was the highest for both roots and entire plant biomass, with more than 800 mg kg(-1) of copper in whole plant. The highest potential copper phytoextraction by perennial peanut was in Inceptisol soil with copper removal of 2,500 g ha(-1). Also, perennial peanut showed high potential for copper phytoremoval in copper mining waste and Mollisol with 1,700 and 1,500 g of copper per hectare, respectively. In addition, perennial peanuts characterized high potential for phytoextraction and phytostabilization of copper in vineyard soils and copper mining waste.

  9. Metal cotolerance to copper, lead, and zinc in Festuca rubra

    SciTech Connect

    Wong, M.H.

    1982-10-01

    Tillers of red fescue (Festuca rubra) were collected from three copper-contaminated sites: Prescot (Lancashire, near the copper refinery factory), Great Orme (Clwyd, copper mine), and Ecton (Staffordshire, copper mine), as well as from an uncontaminated area (Festuca rubra S59). By comparing their indexes of tolerance, it was discovered that tillers from Ecton which contained a rather high level of copper, lead, and zinc were tolerant to all three metals. This variety of F. rubra would be useful for reclaiming nonferrous mine spoils which contain a high level of the three commonly occurring heavy metals, i.e., copper, lead and zinc.

  10. Endophytic Chaetomium globosum enhances maize seedling copper stress tolerance.

    PubMed

    Abou Alhamed, M F; Shebany, Y M

    2012-09-01

    This study aims at characterisation of the impact of Chaetomium globosum on copper stress resistance of maize seedlings. Higher levels of copper treatment decreased maize dry weight and induced a marked increase in osmotic solutes, antioxidant enzyme activity and the level of lipid peroxidation. On the other hand, addition of the endophytic C. globosum alleviated the toxic effect of copper on maize growth. The combination of copper sulphate and Chaetomium increased seedling dry weight, osmotic solute content and antioxidant enzyme activity compared to copper sulphate alone, while lipid peroxidation levels were also decreased. The fungal scavenger system might be important for supporting the ability of maize seedlings to resist copper toxicity.

  11. Copper in microbial pathogenesis: meddling with the metal.

    PubMed

    Samanovic, Marie I; Ding, Chen; Thiele, Dennis J; Darwin, K Heran

    2012-02-16

    Transition metals such as iron, zinc, copper, and manganese are essential for the growth and development of organisms ranging from bacteria to mammals. Numerous studies have focused on the impact of iron availability during bacterial and fungal infections, and increasing evidence suggests that copper is also involved in microbial pathogenesis. Not only is copper an essential cofactor for specific microbial enzymes, but several recent studies also strongly suggest that copper is used to restrict pathogen growth in vivo. Here, we review evidence that animals use copper as an antimicrobial weapon and that, in turn, microbes have developed mechanisms to counteract the toxic effects of copper.

  12. Utilization of Copper Alloys for Marine Applications

    NASA Astrophysics Data System (ADS)

    Drach, Andrew

    Utilization of copper alloy components in systems deployed in marine environment presents potential improvements by reducing maintenance costs, prolonging service life, and increasing reliability. However, integration of these materials faces technological challenges, which are discussed and addressed in this work, including characterization of material performance in seawater environment, hydrodynamics of copper alloy components, and design procedures for systems with copper alloys. To characterize the hydrodynamic behavior of copper alloy nets, mesh geometry of the major types of copper nets currently used in the marine aquaculture are analyzed and formulae for the solidity and strand length are proposed. Experimental studies of drag forces on copper alloy net panels are described. Based on these studies, empirical values for normal drag coefficients are proposed for various types of copper netting. These findings are compared to the previously published data on polymer nets. It is shown that copper nets exhibit significantly lower resistance to normal currents, which corresponds to lower values of normal drag coefficient. The seawater performance (corrosion and biofouling) of copper alloys is studied through the field trials of tensioned and untensioned specimens in a one-year deployment in the North Atlantic Ocean. The corrosion behavior is characterized by weight loss, optical microscopy, and SEM/EDX analyses. The biofouling performance is quantified in terms of the biomass accumulation. To estimate the effects of stray electrical currents on the seawater corrosion measurements, a low cost three-axis stray electric current monitoring device is designed and tested both in the lab and in the 30-day field deployment. The system consists of a remotely operated PC with a set of pseudo-electrodes and a digital compass. The collected data is processed to determine magnitudes of AC and DC components of electric field and dominant AC frequencies. Mechanical behavior of

  13. Serum copper and zinc levels and copper/zinc ratio in patients with breast cancer.

    PubMed

    Yücel, I; Arpaci, F; Ozet, A; Döner, B; Karayilanoğlu, T; Sayar, A; Berk, O

    1994-01-01

    Serum copper, zinc levels, and the Cu/Zn ratio were evaluated in 31 patients with breast cancer and 35 healthy controls. Copper and zinc were determined by atomic absorbtion spectrophotometry. The mean serum copper level and the mean Cu/Zn ratio in patients with breast cancer were significantly higher than the control group (p < 0.001 and p < 0.001). In addition, the mean serum zinc level in patients with breast cancer was significantly lower than the control group (p < 0.001). Neither serum copper and zinc levels nor the Cu/Zn ratio were of value in discriminating of the disease activity and severity. Interestingly, the Cu/Zn ratio in premenopausal patients was higher than postmenopausal patients (p < 0.05) and this was not related to age. The further combined biological and epidemiological studies are necessary to investigate the roles of copper and zinc in breast cancer.

  14. Magnetic field effects on copper metal deposition from copper sulfate aqueous solution.

    PubMed

    Udagawa, Chikako; Maeda, Aya; Katsuki, Akio; Maki, Syou; Morimoto, Shotaro; Tanimoto, Yoshifumi

    2014-05-08

    Effects of a magnetic field (≤0.5 T) on electroless copper metal deposition from the reaction of a copper sulfate aqueous solution and a zinc thin plate were examined in this study. In a zero field, a smooth copper thin film grew steadily on the plate. In a 0.38 T field, a smooth copper thin film deposited on a zinc plate within about 1 min. Then, it peeled off repeatedly from the plate. The yield of consumed copper ions increased about 2.1 times compared with that in a zero field. Mechanism of this magnetic field effect was discussed in terms of Lorentz force- and magnetic force-induced convection and local volta cell formation.

  15. Extracting copper from copper oxide ore by a zwitterionic reagent and dissolution kinetics

    NASA Astrophysics Data System (ADS)

    Deng, Jiu-shuai; Wen, Shu-ming; Deng, Jian-ying; Wu, Dan-dan

    2015-03-01

    Sulfamic acid (SA), which possesses a zwitterionic structure, was applied as a leaching reagent for the first time for extracting copper from copper oxide ore. The effects of reaction time, temperature, particle size, reagent concentration, and stirring speed on this leaching were studied. The dissolution kinetics of malachite was illustrated with a three-dimensional diffusion model. A novel leaching effect of SA on malachite was eventually demonstrated. The leaching rate increased with decreasing particle size and increasing concentration, reaction temperature and stirring speed. The activation energy for SA leaching malachite was 33.23 kJ/mol. Furthermore, the effectiveness of SA as a new reagent for extracting copper from copper oxide ore was confirmed by experiment. This approach may provide a solution suitable for subsequent electrowinning. In addition, results reported herein may provide basic data that enable the leaching of other carbonate minerals of copper, zinc, cobalt and so on in an SA system.

  16. Thermal stability of copper silicide passivation layers in copper-based multilevel interconnects

    NASA Astrophysics Data System (ADS)

    Hymes, S.; Kumar, K. S.; Murarka, S. P.; Ding, P. J.; Wang, W.; Lanford, W. A.

    1998-04-01

    Copper thin films were exposed to a dilute silane mixture at temperatures in the range of 190-363 °C. The resulting silicide surface layers were characterized by four-point probe, Rutherford backscattering spectrometry, and x-ray diffraction. A definitive stability regime is observed in which progressively higher copper content phases exist with increasing temperature. Cu3Si, formed in silane, on annealing converts to Cu5Si and eventually to no silicide layer by a silicon diffusion reaction that in an inert ambient drives silicon into underlying copper to form a solid solution. In oxidizing ambients, a similar phenomenon occurs but now silicon also diffuses to surfaces where it oxidizes to form a self-passivating SiO2 layer on surface. These results have important implications governing integration of copper silicide as a passivation layer and silicon hydride based dielectric deposition in copper-based multilevel interconnect in ultralarge scale integration.

  17. Copper(I) electrode function of two types of copper(II) ion-selective electrodes.

    PubMed

    Neshkova, M; Sheytanov, H

    1985-08-01

    The response of two types of solid-state copper ion-selective electrodes with homogeneous membranes of CuAgSe and Cu(2-x)Se has been investigated in copper(I) solutions, prepared electrochemically by insitu generation from a copper anode in chloride medium. The selectivity coefficient K(pot)(Cu+, Cu(2+)) both types of electrodes has been determined. It is 10(-5.7) for the copper selenide sensor, and 10(-6.2) for the copper silver selenide one. These values are very close to that calculated for an exchange reaction proceeding on the electrode surface. The similarity in K(pot)(Cu+ ,Cu(2+)) values for different chalcogenidebased sensors suggests a common potential-generating mechanism. High chloride concentration does not interfere with the electrode response towards Cu(I), but distorts the electrode response to Cu(II).

  18. The Copper Balance of Cities

    PubMed Central

    Kral, Ulrich; Lin, Chih-Yi; Kellner, Katharina; Ma, Hwong-wen; Brunner, Paul H

    2014-01-01

    Material management faces a dual challenge: on the one hand satisfying large and increasing demands for goods and on the other hand accommodating wastes and emissions in sinks. Hence, the characterization of material flows and stocks is relevant for both improving resource efficiency and environmental protection. This article focuses on the urban scale, a dimension rarely investigated in past metal flow studies. We compare the copper (Cu) metabolism of two cities in different economic states, namely, Vienna (Europe) and Taipei (Asia). Substance flow analysis is used to calculate urban Cu balances in a comprehensive and transparent form. The main difference between Cu in the two cities appears to be the stock: Vienna seems close to saturation with 180 kilograms per capita (kg/cap) and a growth rate of 2% per year. In contrast, the Taipei stock of 30 kg/cap grows rapidly by 26% per year. Even though most Cu is recycled in both cities, bottom ash from municipal solid waste incineration represents an unused Cu potential accounting for 1% to 5% of annual demand. Nonpoint emissions are predominant; up to 50% of the loadings into the sewer system are from nonpoint sources. The results of this research are instrumental for the design of the Cu metabolism in each city. The outcomes serve as a base for identification and recovery of recyclables as well as for directing nonrecyclables to appropriate sinks, avoiding sensitive environmental pathways. The methodology applied is well suited for city benchmarking if sufficient data are available. PMID:25866460

  19. Vitrification of copper flotation waste.

    PubMed

    Karamanov, Alexander; Aloisi, Mirko; Pelino, Mario

    2007-02-09

    The vitrification of an hazardous iron-rich waste (W), arising from slag flotation of copper production, was studied. Two glasses, containing 30wt% W were melted for 30min at 1400 degrees C. The first batch, labeled WSZ, was obtained by mixing W, blast furnace slag (S) and zeolite tuff (Z), whereas the second, labeled WG, was prepared by mixing W, glass cullet (G), sand and limestone. The glass frits showed high chemical durability, measured by the TCLP test. The crystallization of the glasses was evaluated by DTA. The crystal phases formed were identified by XRD resulting to be pyroxene and wollastonite solid solutions, magnetite and hematite. The morphology of the glass-ceramics was observed by optical and scanning electron microscopy. WSZ composition showed a high rate of bulk crystallization and resulted to be suitable for producing glass-ceramics by a short crystallization heat-treatment. WG composition showed a low crystallization rate and good sinterability; glass-ceramics were obtained by sinter-crystallization of the glass frit.

  20. Grain Boundary Energies in Copper.

    NASA Astrophysics Data System (ADS)

    Omar, Ramli

    Available from UMI in association with The British Library. Requires signed TDF. The dependence of grain boundary energy on boundary orientation was studied in copper annealed at 1000 ^circC. Grain boundary orientations and the disorientations across the boundaries were measured. A rotation matrix notation is used to interpret selected area electron channelling patterns observed in a scanning electron microscope. The Herring and Shewmon torque terms were investigated using wire specimens having a "bamboo" structure. The Herring torque terms were determined using the Hess relation. The (110) section of the Sigma 11 gamma-plot (i.e. the variation of grain boundary energy with boundary orientation) was evaluated. In this plot, minima in energies were found at the (311) and (332) mirror planes. Sigma 3 and Sigma9 boundaries were investigated in sheet specimens. The (110) and (111) sections of the Sigma3 gamma -plot were evaluated. In addition to the sharp cusps occurring at the Sigma3 {111} planes, the further shallower cusps occur at the incoherent Sigma 3 boundaries with the interfacial planes approximately parallel to {322} in one crystal and {11.44} in the other crystal. Flat and curved Sigma9 boundaries were investigated. The break up of Sigma9 boundaries into two Sigma3 boundaries and the relation between the Sigma3 and Sigma 9 gamma-plots was also examined. The (110) section of the Sigma9 gamma-plot was constructed.

  1. Nondestructive tests of regenerative chambers. [evaluating nondestructive methods of determining metal bond integrity

    NASA Technical Reports Server (NTRS)

    Malone, G. A.; Vecchies, L.; Wood, R.

    1974-01-01

    The capabilities and limitations of nondestructive evaluation methods were studied to detect and locate bond deficiencies in regeneratively cooled thrust chambers for rocket engines. Flat test panels and a cylinder were produced to simulate regeneratively cooled thrust chamber walls. Planned defects with various bond integrities were produced in the panels to evaluate the sensitivity, accuracy, and limitations of nondestructive methods to define and locate bond anomalies. Holography, acoustic emission, and ultrasonic scan were found to yield sufficient data to discern bond quality when used in combination and in selected sequences. Bonding techniques included electroforming and brazing. Materials of construction included electroformed nickel bonded to Nickel 200 and OFHC copper, electroformed copper bonded to OFHC copper, and 300 series stainless steel brazed to OFHC copper. Variations in outer wall strength, wall thickness, and defect size were evaluated for nondestructive test response.

  2. Development of highly faceted reduced graphene oxide-coated copper oxide and copper nanoparticles on a copper foil surface.

    PubMed

    Ortega-Amaya, Rebeca; Matsumoto, Yasuhiro; Espinoza-Rivas, Andrés M; Pérez-Guzmán, Manuel A; Ortega-López, Mauricio

    2016-01-01

    This work describes the formation of reduced graphene oxide-coated copper oxide and copper nanoparticles (rGO-Cu2ONPs, rGO-CuNPs) on the surface of a copper foil supporting graphene oxide (GO) at annealing temperatures of 200-1000 °C, under an Ar atmosphere. These hybrid nanostructures were developed from bare copper oxide nanoparticles which grew at an annealing temperature of 80 °C under nitrogen flux. The predominant phase as well as the particle size and shape strongly depend on the process temperature. Characterization with transmission electron microscopy and scanning electron microscopy indicates that Cu or Cu2O nanoparticles take rGO sheets from the rGO network to form core-shell Cu-rGO or Cu2O-rGO nanostructures. It is noted that such ones increase in size from 5 to 800 nm as the annealing temperature increases in the 200-1000 °C range. At 1000 °C, Cu nanoparticles develop a highly faceted morphology, displaying arm-like carbon nanorods that originate from different facets of the copper crystal structure.

  3. Development of highly faceted reduced graphene oxide-coated copper oxide and copper nanoparticles on a copper foil surface

    PubMed Central

    Matsumoto, Yasuhiro; Espinoza-Rivas, Andrés M; Pérez-Guzmán, Manuel A; Ortega-López, Mauricio

    2016-01-01

    Summary This work describes the formation of reduced graphene oxide-coated copper oxide and copper nanoparticles (rGO-Cu2ONPs, rGO-CuNPs) on the surface of a copper foil supporting graphene oxide (GO) at annealing temperatures of 200–1000 °C, under an Ar atmosphere. These hybrid nanostructures were developed from bare copper oxide nanoparticles which grew at an annealing temperature of 80 °C under nitrogen flux. The predominant phase as well as the particle size and shape strongly depend on the process temperature. Characterization with transmission electron microscopy and scanning electron microscopy indicates that Cu or Cu2O nanoparticles take rGO sheets from the rGO network to form core–shell Cu–rGO or Cu2O–rGO nanostructures. It is noted that such ones increase in size from 5 to 800 nm as the annealing temperature increases in the 200–1000 °C range. At 1000 °C, Cu nanoparticles develop a highly faceted morphology, displaying arm-like carbon nanorods that originate from different facets of the copper crystal structure. PMID:27547618

  4. Copper transporter 2 regulates intracellular copper and sensitivity to cisplatin.

    PubMed

    Huang, Carlos P; Fofana, Mariama; Chan, Jefferson; Chang, Christopher J; Howell, Stephen B

    2014-03-01

    Mammalian cells express two copper (Cu) influx transporters, CTR1 and CTR2. CTR1 serves as an influx transporter for both Cu and cisplatin (cDDP). In mouse embryo fibroblasts, reduction of CTR1 expression renders cells resistant to cDDP whereas reduction of CTR2 makes them hypersensitive both in vitro and in vivo. To investigate the role of CTR2 on intracellular Cu and cDDP sensitivity its expression was molecularly altered in the human epithelial 2008 cancer cell model. Intracellular exchangeable Cu(+) was measured with the fluorescent probe Coppersensor-3 (CS3). The ability of CS3 to report on changes in intracellular Cu(+) was validated by showing that Cu chelators reduced its signal, and that changes in signal accompanied alterations in expression of the major Cu influx transporter CTR1 and the two Cu efflux transporters, ATP7A and ATP7B. Constitutive knock down of CTR2 mRNA by ∼50% reduced steady-state exchangeable Cu by 22-23% and increased the sensitivity of 2008 cells by a factor of 2.6-2.9 in two separate clones. Over-expression of CTR2 increased exchangeable Cu(+) by 150% and rendered the 2008 cells 2.5-fold resistant to cDDP. The results provide evidence that CS3 can quantitatively assess changes in exchangeable Cu(+), and that CTR2 regulates both the level of exchangeable Cu(+) and sensitivity to cDDP in a model of human epithelial cancer. This study introduces CS3 and related sensors as novel tools for probing and assaying Cu-dependent sensitivity to anticancer therapeutics.

  5. Determination of the taste threshold of copper in water.

    PubMed

    Zacarías, I; Yáñez, C G; Araya, M; Oraka, C; Olivares, M; Uauy, R

    2001-01-01

    Copper effects on human health represent a relevant issue in modern nutrition. One of the difficulties in assessing the early, acute effects of copper ingested via drinking water is that the taste of copper may influence the response and the capacity to taste copper in different waters is unknown. The purpose of the study was to determine the taste threshold of copper in different types of water, using soluble and insoluble salts (copper sulfate and copper chloride). Copper-containing solutions (range 1.0-8.0 mg/l Cu) were prepared in tap water, distilled deionized water and uncarbonated mineral water. Sixty-one healthy volunteers (17-50 years of age), with no previous training for sensory evaluation, participated in the study. A modified triangle test was used to define the taste threshold value. The threshold was defined as the lowest copper concentration detected by 50% of the subjects assessed. To evaluate the olfactory input in the threshold value obtained, 15 of 61 subjects underwent a second set of triangle tests with the nose open and clamped, using distilled water with copper sulfate at a concentration corresponding to the individual's threshold. The taste threshold in tap water was 2.6 mg/l Cu for both copper sulfate and copper chloride. The corresponding values for distilled deionized water were 2.4 and 2.5 mg/l Cu for copper sulfate and copper chloride, respectively. In uncarbonated mineral water the threshold values were slightly higher, 3.5 and 3.8 mg/l Cu for copper sulfate and for copper chloride, respectively, which are significantly higher than those observed in tap and distilled waters (P < 0.01, Kruskal-Wallis test). The taste threshold did not change significantly when the nose was clamped. In conclusion, the median values for copper taste threshold were low, ranging between 2.4 and 3.8 mg/l Cu, depending on the type of water.

  6. Astrocyte functions in the copper homeostasis of the brain.

    PubMed

    Scheiber, Ivo F; Dringen, Ralf

    2013-04-01

    Copper is an essential element that is required for a variety of important cellular functions. Since not only copper deficiency but also excess of copper can seriously affect cellular functions, the cellular copper metabolism is tightly regulated. In brain, astrocytes appear to play a pivotal role in the copper metabolism. With their strategically important localization between capillary endothelial cells and neuronal structures they are ideally positioned to transport copper from the blood-brain barrier to parenchymal brain cells. Accordingly, astrocytes have the capacity to efficiently take up, store and to export copper. Cultured astrocytes appear to be remarkably resistant against copper-induced toxicity. However, copper exposure can lead to profound alterations in the metabolism of these cells. This article will summarize the current knowledge on the copper metabolism of astrocytes, will describe copper-induced alterations in the glucose and glutathione metabolism of astrocytes and will address the potential role of astrocytes in the copper metabolism of the brain in diseases that have been connected with disturbances in brain copper homeostasis.

  7. Copper at synapse: Release, binding and modulation of neurotransmission.

    PubMed

    D'Ambrosi, Nadia; Rossi, Luisa

    2015-11-01

    Over the last decade, a piece of the research studying copper role in biological systems was devoted to unravelling a still elusive, but extremely intriguing, aspect that is the involvement of copper in synaptic function. These studies were prompted to provide a rationale to the finding that copper is released in the synaptic cleft upon depolarization. The copper pump ATP7A, which mutations are responsible for diseases with a prominent neurodegenerative component, seems to play a pivotal role in the release of copper at synapses. Furthermore, it was found that, when in the synaptic cleft, copper can control, directly or indirectly, the activity of the neurotransmitter receptors (NMDA, AMPA, GABA, P2X receptors), thus affecting excitability. In turn, neurotransmission can affect copper trafficking and delivery in neuronal cells. Furthermore, it was reported that copper can also modulate synaptic vesicles trafficking and the interaction between proteins of the secretory pathways. Interestingly, proteins with a still unclear role in neuronal system though associated with the pathogenesis of neurodegenerative diseases (the amyloid precursor protein, APP, the prion protein, PrP, α-synuclein, α-syn) show copper-binding domains. They may act as copper buffer at synapses and participate in the interplay between copper and the neurotransmitters receptors. Given that copper dysmetabolism occurs in several diseases affecting central and peripheral nervous system, the findings on the contribution of copper in synaptic transmission, beside its more consolidate role as a neuronal enzymes cofactor, may open new insights for therapy interventions.

  8. Organic ligands reduce copper toxicity in Pseudomonas syringae

    SciTech Connect

    Azenha, M.; Vasconcelos, M.T.; Cabral, J.P.S.

    1995-03-01

    Pseudomonas syringae cells were exposed to 100 {mu}M copper alone, or to previously equilibrated copper sulfate-ligand solutions. Ligand concentrations were determined experimentally as those that reduced the free copper concentration to 5 {mu}M (determined with a Cu{sup 2+}-selective electrode). These values were in agreement with those calculated by computational equilibrium simulation based on published stability constants. Exposure of P. syringae cells to copper sulfate, chloride, or nitrate resulted in similar high mortality, suggesting that copper was responsible for cell death. Acetate, succinate, proline, lysine, cysteine, and EDTA significantly reduced both the amount of copper bound to the cells and cell death, indicating that not only strong chelating agents but also weak and moderate copper ligands can effectively antagonize copper toxicity. However, cysteine and EDTA were considerably more effective than acetate, succinate, proline, and lysine, indicating that copper toxicity is not simply a function of free copper concentration but depends on the nature of the ligand. The results suggested that a significant fraction of copper bound to acetate, succinate, proline, or lysine was displaced to the bacteria or, alternatively, mixed copper-ligand-cell complexes could be formed. On the contrary, none of these phenomena occurred for the copper complexes with cysteine or EDTA.

  9. Copper Resistance of the Emerging Pathogen Acinetobacter baumannii

    PubMed Central

    Williams, Caitlin L.; Neu, Heather M.; Gilbreath, Jeremy J.; Michel, Sarah L. J.; Zurawski, Daniel V.

    2016-01-01

    ABSTRACT Acinetobacter baumannii is an important emerging pathogen that is capable of causing many types of severe infection, especially in immunocompromised hosts. Since A. baumannii can rapidly acquire antibiotic resistance genes, many infections are on the verge of being untreatable, and novel therapies are desperately needed. To investigate the potential utility of copper-based antibacterial strategies against Acinetobacter infections, we characterized copper resistance in a panel of recent clinical A. baumannii isolates. Exposure to increasing concentrations of copper in liquid culture and on solid surfaces resulted in dose-dependent and strain-dependent effects; levels of copper resistance varied broadly across isolates, possibly resulting from identified genotypic variation among strains. Examination of the growth-phase-dependent effect of copper on A. baumannii revealed that resistance to copper increased dramatically in stationary phase. Moreover, A. baumannii biofilms were more resistant to copper than planktonic cells but were still susceptible to copper toxicity. Exposure of bacteria to subinhibitory concentrations of copper allowed them to better adapt to and grow in high concentrations of copper; this copper tolerance response is likely achieved via increased expression of copper resistance mechanisms. Indeed, genomic analysis revealed numerous putative copper resistance proteins that share amino acid homology to known proteins in Escherichia coli and Pseudomonas aeruginosa. Transcriptional analysis revealed significant upregulation of these putative copper resistance genes following brief copper exposure. Future characterization of copper resistance mechanisms may aid in the search for novel antibiotics against Acinetobacter and other highly antibiotic-resistant pathogens. IMPORTANCE Acinetobacter baumannii causes many types of severe nosocomial infections; unfortunately, some isolates have acquired resistance to almost every available antibiotic

  10. Electrodialytic remediation of copper mine tailings.

    PubMed

    Hansen, Henrik K; Rojo, Adrián; Ottosen, Lisbeth M

    2005-01-31

    Mining activities in Chile have generated large amounts of solid waste, which have been deposited in mine tailing impoundments. These impoundments cause concern to the communities due to dam failures or natural leaching to groundwater and rivers. This work shows the laboratory results of nine electrodialytic remediation experiments on copper mine tailings. The results show that electric current could remove copper from watery tailing if the potential gradient was higher than 2 V/cm during 21 days. With addition of sulphuric acid, the process was enhanced because the pH decreased to around 4, and the copper by this reason was released in the solution. Furthermore, with acidic tailing the potential gradient was less than 2 V/cm. The maximum copper removal reached in the anode side was 53% with addition of sulphuric acid in 21 days experiment at 20 V using approximately 1.8 kg mine tailing on dry basis. In addition, experiments with acidic tailing show that the copper removal is proportional with time.

  11. Optical properties of stabilized copper nanoparticles

    NASA Astrophysics Data System (ADS)

    Mohindroo, Jeevan Jyoti; Garg, Umesh Kumar; Sharma, Anshul Kumar

    2016-05-01

    Optical studies involving calculation of Band Gap of the synthesized copper nanoparticles were carried out in the wavelength range of 500 to 650 nm at room temperature, the particles showed high absorption at 550nm indicating their good absorptive properties. In this method water is used as the medium for reduction of copper ions in to copper Nanoparticles the stabilization of copper Nanoparticles was studied with starch both as a reductant and stabilizer,. The reaction mixture was heated using a kitchen microwave for about 5 minutes to attain the required temp for the reaction. The pH of the solution was adjusted to alkaline using 5%solution of NaOH. Formation of Copper Nanoparticles was indicated by change in color of the solution from blue to yellowish black which is supported by the UV absorption at 570nm.the synthesized particles were washed with water and alcohol. The optical properties depend upon absorption of radiations which in turn depends upon ratio of electrons and holes present in the material and also on the shape of the nanoparticles. In the present investigation it was observed that optical absorption increases with increase in particle size. The optical band gap for the Nanoparticles was obtained from plots between hv vs. (αhv)2 and hv vs. (αhv)1/2. The value of Band gap came out to be around 1.98-2.02 eV which is in close agreement with the earlier reported values

  12. 40 CFR 421.60 - Applicability: Description of the secondary copper subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... secondary copper subcategory. 421.60 Section 421.60 Protection of Environment ENVIRONMENTAL PROTECTION... CATEGORY Secondary Copper Subcategory § 421.60 Applicability: Description of the secondary copper..., processing, and remelting of new and used copper scrap and residues to produce copper metal and copper...

  13. 40 CFR 421.60 - Applicability: Description of the secondary copper subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... secondary copper subcategory. 421.60 Section 421.60 Protection of Environment ENVIRONMENTAL PROTECTION... CATEGORY Secondary Copper Subcategory § 421.60 Applicability: Description of the secondary copper..., processing, and remelting of new and used copper scrap and residues to produce copper metal and copper...

  14. 40 CFR 421.60 - Applicability: Description of the secondary copper subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... secondary copper subcategory. 421.60 Section 421.60 Protection of Environment ENVIRONMENTAL PROTECTION... CATEGORY Secondary Copper Subcategory § 421.60 Applicability: Description of the secondary copper..., processing, and remelting of new and used copper scrap and residues to produce copper metal and copper...

  15. 40 CFR 421.60 - Applicability: Description of the secondary copper subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... secondary copper subcategory. 421.60 Section 421.60 Protection of Environment ENVIRONMENTAL PROTECTION... CATEGORY Secondary Copper Subcategory § 421.60 Applicability: Description of the secondary copper..., processing, and remelting of new and used copper scrap and residues to produce copper metal and copper...

  16. 40 CFR 421.60 - Applicability: Description of the secondary copper subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... secondary copper subcategory. 421.60 Section 421.60 Protection of Environment ENVIRONMENTAL PROTECTION... CATEGORY Secondary Copper Subcategory § 421.60 Applicability: Description of the secondary copper..., processing, and remelting of new and used copper scrap and residues to produce copper metal and copper...

  17. Design considerations for the TF center conductor post for the Ignition Spherical Torus (IST)

    SciTech Connect

    Dalton, G.R.; Haines, J.R.

    1986-01-01

    A trade-off study has been carried out to compare the differential costs of using high-strength alloy copper versus oxygen-free, high-conductivity (OFHC) copper for the center legs of the toroidal field (TF) coils of an Ignition Spherical Torus (IST). The electrical heating, temperatures, stresses, cooling requirements, material costs, pump costs, and power to drive the TF coils and pumps are all assessed for both materials for a range of compact tokamak reactors. The alloy copper material is found to result in a more compact reactor and to allow use of current densities of up to 170 MA/mS versus 40 MA/mS for the OFHC copper. The OFHC conductor system with high current density is $24 million less expensive than more conventional copper systems with 30 MA/mS. The alloy copper system costs $32 million less than conventional systems. Therefore, the alloy system offers a net savings of $8 million compared to the 50% cold-worked OFHC copper system. Although the savings are a significant fraction of the center conductor post cost, they are relatively insignificant in terms of the total device cost. It is concluded that the use of alloy copper contributes very little to the economic or technical viability of the compact IST. It is recommended that a similar systematic approach be applied to evaluating coil material and current density trade-offs for other compact copper-TF-coil tokamak designs. 9 refs., 13 figs., 13 tabs.

  18. Metallic copper corrosion rates, moisture content, and growth medium influence survival of copper ion-resistant bacteria.

    PubMed

    Elguindi, Jutta; Moffitt, Stuart; Hasman, Henrik; Andrade, Cassandra; Raghavan, Srini; Rensing, Christopher

    2011-03-01

    The rapid killing of various bacteria in contact with metallic copper is thought to be influenced by the influx of copper ions into the cells, but the exact mechanism is not fully understood. This study showed that the kinetics of contact killing of copper surfaces depended greatly on the amount of moisture present, copper content of alloys, type of medium used, and type of bacteria. We examined antibiotic- and copper ion-resistant strains of Escherichia coli and Enterococcus faecium isolated from pig farms following the use of copper sulfate as feed supplement. The results showed rapid killing of both copper ion-resistant E. coli and E. faecium strains when samples in rich medium were spread in a thin, moist layer on copper alloys with 85% or greater copper content. E. coli strains were rapidly killed under dry conditions, while E. faecium strains were less affected. Electroplated copper surface corrosion rates were determined from electrochemical polarization tests using the Stern-Geary method and revealed decreased corrosion rates with benzotriazole and thermal oxide coating. Copper ion-resistant E. coli and E. faecium cells suspended in 0.8% NaCl showed prolonged survival rates on electroplated copper surfaces with benzotriazole coating and thermal oxide coating compared to surfaces without anti-corrosion treatment. Control of surface corrosion affected the level of copper ion influx into bacterial cells, which contributed directly to bacterial killing.

  19. Trace elements in human physiology and pathology. Copper.

    PubMed

    Tapiero, H; Townsend, D M; Tew, K D

    2003-11-01

    Copper is a trace element, important for the function of many cellular enzymes. Copper ions can adopt distinct redox states oxidized Cu(II) or reduced (I), allowing the metal to play a pivotal role in cell physiology as a catalytic cofactor in the redox chemistry of enzymes, mitochondrial respiration, iron absorption, free radical scavenging and elastin cross-linking. If present in excess, free copper ions can cause damage to cellular components and a delicate balance between the uptake and efflux of copper ions determines the amount of cellular copper. In biological systems, copper homeostasis has been characterized at the molecular level. It is coordinated by several proteins such as glutathione, metallothionein, Cu-transporting P-type ATPases, Menkes and Wilson proteins and by cytoplasmic transport proteins called copper chaperones to ensure that it is delivered to specific subcellular compartments and thereby to copper-requiring proteins.

  20. A limited legacy effect of copper in marine biofilms.

    PubMed

    McElroy, David J; Doblin, Martina A; Murphy, Richard J; Hochuli, Dieter F; Coleman, Ross A

    2016-08-15

    The effects of confounding by temporal factors remains understudied in pollution ecology. For example, there is little understanding of how disturbance history affects the development of assemblages. To begin addressing this gap in knowledge, marine biofilms were subjected to temporally-variable regimes of copper exposure and depuration. It was expected that the physical and biological structure of the biofilms would vary in response to copper regime. Biofilms were examined by inductively coupled plasma optical emission spectrometry, chlorophyll-a fluorescence and field spectrometry and it was found that (1) concentrations of copper were higher in those biofilms exposed to copper, (2) concentrations of copper remain high in biofilms after the source of copper is removed, and (3) exposure to and depuration from copper might have comparable effects on the photosynthetic microbial assemblages in biofilms. The persistence of copper in biofilms after depuration reinforces the need for consideration of temporal factors in ecology.

  1. Effect of copper impurity on polycrystalline silicon solar cells

    NASA Technical Reports Server (NTRS)

    Daud, T.; Koliwad, K. M.

    1978-01-01

    The presence of copper impurity, up to 10 to the 15th atoms/cc, in single crystal silicon has been shown to have no deleterious effect on the p-n junction solar cell performance. However, in polycrystalline silicon, copper atoms tend to migrate to the defect sites because of the structural sensitive properties of copper. This study was undertaken to investigate the influence of this behavior of copper impurity on the performance of p-n junction solar cells fabricated from structurally imperfect silicon. Two sets of polycrystalline silicon substrates containing copper were examined. In one set of samples, copper was incorporated during growth, whereas in the other, copper was diffused. Solar cells were fabricated on both the sets of substrates by a standard process. Dark and light I-V and spectral response characteristics of the cells were measured and compared with copper-free polycrystalline silicon solar cells. The results and the model are discussed.

  2. High-strength braze joints between copper and steel

    NASA Technical Reports Server (NTRS)

    Kuhn, R. F.

    1967-01-01

    High-strength braze joints between copper and steel are produced by plating the faying surface of the copper with a layer of gold. This reduces porosity in the braze area and strengthens the resultant joint.

  3. The conflict between copper grounding systems and CP

    SciTech Connect

    Kirkpatrick, E.L.; Shamim, M.

    1999-09-01

    The common bonding of underground ferrous structures to massive copper grounding grids creates problems for corrosion engineers and their attempts to cathodically protect the ferrous structures. Conflicts between copper and ferrous underground systems are discussed and alternatives are presented.

  4. Pathogenic adaptations to host-derived antibacterial copper.

    PubMed

    Chaturvedi, Kaveri S; Henderson, Jeffrey P

    2014-01-01

    Recent findings suggest that both host and pathogen manipulate copper content in infected host niches during infections. In this review, we summarize recent developments that implicate copper resistance as an important determinant of bacterial fitness at the host-pathogen interface. An essential mammalian nutrient, copper cycles between copper (I) (Cu(+)) in its reduced form and copper (II) (Cu(2+)) in its oxidized form under physiologic conditions. Cu(+) is significantly more bactericidal than Cu(2+) due to its ability to freely penetrate bacterial membranes and inactivate intracellular iron-sulfur clusters. Copper ions can also catalyze reactive oxygen species (ROS) generation, which may further contribute to their toxicity. Transporters, chaperones, redox proteins, receptors and transcription factors and even siderophores affect copper accumulation and distribution in both pathogenic microbes and their human hosts. This review will briefly cover evidence for copper as a mammalian antibacterial effector, the possible reasons for this toxicity, and pathogenic resistance mechanisms directed against it.

  5. Pathogenic adaptations to host-derived antibacterial copper

    PubMed Central

    Chaturvedi, Kaveri S.; Henderson, Jeffrey P.

    2014-01-01

    Recent findings suggest that both host and pathogen manipulate copper content in infected host niches during infections. In this review, we summarize recent developments that implicate copper resistance as an important determinant of bacterial fitness at the host-pathogen interface. An essential mammalian nutrient, copper cycles between copper (I) (Cu+) in its reduced form and copper (II) (Cu2+) in its oxidized form under physiologic conditions. Cu+ is significantly more bactericidal than Cu2+ due to its ability to freely penetrate bacterial membranes and inactivate intracellular iron-sulfur clusters. Copper ions can also catalyze reactive oxygen species (ROS) generation, which may further contribute to their toxicity. Transporters, chaperones, redox proteins, receptors and transcription factors and even siderophores affect copper accumulation and distribution in both pathogenic microbes and their human hosts. This review will briefly cover evidence for copper as a mammalian antibacterial effector, the possible reasons for this toxicity, and pathogenic resistance mechanisms directed against it. PMID:24551598

  6. 21 CFR 73.2120 - Disodium EDTA-copper.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... practice: Total copper, not less than 13.5 percent. Total (ethylene-dinitrilo) tetracetic acid, not less than 62.5 percent. Free copper, not more than 100 parts per million. Free disodium salt of...

  7. Metals in Metal Salts: A Copper Mirror Demonstration

    ERIC Educational Resources Information Center

    Pike, Robert D.

    2010-01-01

    A simple lecture demonstration is described to show the latent presence of metal atoms in a metal salt. Copper(II) formate tetrahydrate is heated in a round-bottom flask forming a high-quality copper mirror.

  8. Preparation of polyamine-functionalized copper specific adsorbents for selective adsorption of copper.

    PubMed

    Yu, Zhiyuan; Wu, Ren'an; Wu, Minghuo; Zhao, Liang; Li, Ruibin; Zou, Hanfa

    2010-07-01

    The level of serum free copper is greatly elevated in Wilson's disease. For patients with acute Wilson's disease, liver transplantation is the only lifesaving treatment. Plasma exchange or albumin dialysis is often used as a bridge to liver transplantation to maintain a stable clinical status for patients. Hemoperfusion is another effective therapy in removing toxins from the plasma. However, hemoperfusion has not been reported to remove copper due to lack of copper specific adsorbent. In this work, copper chelating agents, triethylenetetramine and tetraethylenepentamine, were covalently immobilized onto macroporous poly(glycidyl methacrylate-co-trimethylolpropane trimethacrylate) microspheres to prepare copper specific adsorbents. The resulting adsorbents demonstrated good adsorption capacities of 63.44 and 58.48 mg/g, respectively, for Cu2+ ion. Additionally, with the interference of other metal ions such as Fe2+, Mg2+, Zn2+ and Ca2+, the prepared copper adsorbents still demonstrated good specificity toward Cu2+ ion. These results indicate that the adsorbents are promising adsorbents in hemoperfusion therapy for selective removal of copper for patients with severe Wilson's disease.

  9. Coordination geometry around copper in a Schiff-base trinuclear copper complex using EXAFS spectroscopy

    NASA Astrophysics Data System (ADS)

    Gaur, Abhijeet; Shrivastava, B. D.; Gaur, D. C.; Prasad, J.; Srivastava, K.; Jha, S. N.; Bhattacharyya, D.; Poswal, A.

    2012-05-01

    In the present investigation, we have studied extended X-ray absorption fine structure (EXAFS) spectra of a trinuclear Schiff-base copper complex tetraaqua-di-μ3-(N-salicylidene-DL-glutamato)-tricopper(II)heptahydrate, [Cu3(C12H10NO5)2 (H2O)4]. 7H2O, in which three metal sites are present. One metal site is square-pyramidal (4+1) and other two similar metal sites are tetragonally distorted octahedral (4+2). EXAFS has been recorded at the K-edge of copper in the complex at the dispersive EXAFS beamline at 2 GeV Indus-2 synchrotron source at RRCAT, Indore, India. The analysis of EXAFS spectra of multinuclear metal complexes pose some problems due to the presence of many absorbing atoms, even when the absorbing atoms may be of the same element. Hence, using the available crystal structure of the complex, theoretical models have been generated for the different copper sites separately, which are then fitted to the experimental EXAFS data. The two coordination geometries around the copper sites have been determined. The contributions of the different copper sites to the experimental spectrum have been estimated. The structural parameters, which include bond-lengths, coordination numbers and thermal disorders, for the two types of copper sites have been reported. Further, copper has been found to be in +2 oxidation state at these metal sites.

  10. Mechanism of Mineral Phase Reconstruction for Improving the Beneficiation of Copper and Iron from Copper Slag

    NASA Astrophysics Data System (ADS)

    Guo, Zhengqi; Zhu, Deqing; Pan, Jan; Zhang, Feng

    2016-09-01

    To maximize the recovery of iron and copper from copper slag, the modification process by adding a compound additive (a mixture of hematite, pyrite and manganous oxide) and optimizing the cooling of the slag was studied. The phase reconstruction mechanism of the slag modification process was revealed by thermodynamic calculations, x-ray diffraction, optical microscopy and scanning electron microscopy. The results show that the synergy between the burnt lime and the compound additive promotes the generation of target minerals, such as magnetite and copper matte. In addition, the multifunctional compound additive is able to improve the fluidity of the molten slag, which facilitates the coalescence and growth of fine particles of the target minerals. As a result, the percentage of iron distributed in the form of magnetite increased from 32.9% to 65.1%, and that of the copper exiting in the form of metallic copper and copper sulfide simultaneously increased from 80.0% to 90.3%. Meanwhile, the grains of the target minerals in the modified slag grew markedly to a mean size of over 50 μm after slow cooling. Ultimately, the beneficiation efficiency of copper and iron was improved because of the ease with which the target minerals could be liberated.

  11. Effect of zinc on copper and iron bioavailability as influenced by dietary copper and fat source

    SciTech Connect

    Magee, A.C.; Jones, B.P.; Lin, F.; Sinthusek, G.; Frimpong, N.A.; Wu, S.

    1986-03-05

    In a number of experiments, they have observed that liver copper levels of young male rats fed low zinc diets were essentially the same as liver copper levels of rats fed adequate zinc. Liver iron levels of rats fed low zinc diets, however, tended to be markedly higher than liver iron levels of rats fed adequate zinc. Increases in dietary zinc (up to 200 ppm) were generally associated with decreases in liver iron deposition, but had little effect on liver copper deposition. Iron bioavailability appeared to be enhanced when fat sources high in saturated fatty acids were used, and there was evidence that the type of dietary fat influenced the effect of zinc on iron bioavailability. Liver copper deposition, however, did not appear to be markedly affected by the type of dietary fat suggesting that copper bioavailability is less affected by fat source. Increases in dietary copper were associated with increases in liver copper levels and decreases in liver iron levels of rats fed increasing levels of zinc. These data suggest that potential interrelationships between dietary factors not being considered as experimental variables could have significant effects on results and on the interrelationships between dietary variables which are being studied.

  12. Thermal resistance across a copper/Kapton/copper interface at cryogenic temperatures

    SciTech Connect

    Zhao, L.; Phelan, P.E.; Niemann, R.C.; Weber, B.R.

    1997-09-01

    The high-{Tc} superconductor current lead heat intercept connection, which is utilized as a thermal intercept to remove the Joule heat from the upper stage lead to a heat sink operating at 50--77 K, consists of a structure where a 152-{micro}m film is sandwiched between two concentric copper cylinders. The material chosen for the insulating film is Kapton MT, a composite film which has a relatively low thermal resistance, but yet a high voltage standoff capability. Here, the measured thermal conductance of a copper/Kapton MT/copper junction in a flat-plate geometry is compared to the results obtained from the actual heat intercept connection. Increasing the contact pressure reduces the thermal resistance to a minimum value determined by the film conduction resistance. A comparison between the resistance of the copper/Kapton MT/copper junction and a copper/G-10/copper junction demonstrates that the Kapton MT layer yields a lower thermal resistance while still providing adequate electrical isolation.

  13. Study of copper silicide retardation effects on copper diffusion in silicon

    NASA Astrophysics Data System (ADS)

    Lee, C. S.; Gong, H.; Liu, R.; Wee, A. T. S.; Cha, C. L.; See, A.; Chan, L.

    2001-10-01

    A B-buried layer with a dose of 1×1014atoms/cm2 was introduced into p-doped Si at a depth of 2.2 μm to enhance copper diffusion via its inherent gettering effect. Copper was then introduced into silicon either via a low-energy implantation followed by a thermal anneal, or through the thermal drive in of physical vapor deposited (PVD) copper film. Secondary ion mass spectrometry depth profiling of both annealed samples later indicated that while substantial amounts of copper was gettered by the B layer in the former sample, no copper was gettered by the B-buried layer in the latter sample. Further analysis with an x-ray diffraction technique showed that copper silicide, Cu3Si was formed in the latter sample. It is thus surmised that the formation of this silicide layer impeded the diffusion of copper towards the B-buried layer. This work investigates the cause of CuSix formation and the underlying reasons for the lower mobility of Cu in PVD Cu film samples.

  14. Behaviour of non-standard composition copper bearing anodes from the copper refining process.

    PubMed

    Marković, R; Friedrich, B; Stajić-Trosić, J; Jordović, B; Jugović, B; Gvozdenović, M; Stevanović, J

    2010-10-15

    This paper addresses on investigation the possibility of electrolytic treatment the sulphur acidic waste solution, obtained in the conventional electrolytic copper refining process. Beside the high copper concentration, the high concentration of other metals, in this case nickel, is the main characteristic of these waste solutions. Due to this fact, the copper bearing anodes with non-standard nickel, lead, tin and antimony content were specially prepared for the refining process. Nickel content of all anodes was approximately 7.5 mass%, and the content of lead, tin and antimony was varied. The preliminary results, obtained using the standard electrochemical techniques, have indicated that the copper bearing anodes could be used under the same conditions as well as in the conventional copper refining process. The measurements in constant galvanostatic pulse have pointed out that the all chemical elements from copper bearing anodes were dissolved and only copper was deposited onto the cathode. It was also pointed out that Ni concentration in the base working electrolyte (sulphur acidic waste solution), after 72 h of process, increased to 102 mass% at T(1)=63+/-2 degrees C and up to 122 mass% at T(1)=73+/-2 degrees C, while arsenic concentration decreased to a minimum value.

  15. Body of Knowledge (BOK) for Copper Wire Bonds

    NASA Technical Reports Server (NTRS)

    Rutkowski, E.; Sampson, M. J.

    2015-01-01

    Copper wire bonds have replaced gold wire bonds in the majority of commercial semiconductor devices for the latest technology nodes. Although economics has been the driving mechanism to lower semiconductor packaging costs for a savings of about 20% by replacing gold wire bonds with copper, copper also has materials property advantages over gold. When compared to gold, copper has approximately: 25% lower electrical resistivity, 30% higher thermal conductivity, 75% higher tensile strength and 45% higher modulus of elasticity. Copper wire bonds on aluminum bond pads are also more mechanically robust over time and elevated temperature due to the slower intermetallic formation rate - approximately 1/100th that of the gold to aluminum intermetallic formation rate. However, there are significant tradeoffs with copper wire bonding - copper has twice the hardness of gold which results in a narrower bonding manufacturing process window and requires that the semiconductor companies design more mechanically rigid bonding pads to prevent cratering to both the bond pad and underlying chip structure. Furthermore, copper is significantly more prone to corrosion issues. The semiconductor packaging industry has responded to this corrosion concern by creating a palladium coated copper bonding wire, which is more corrosion resistant than pure copper bonding wire. Also, the selection of the device molding compound is critical because use of environmentally friendly green compounds can result in internal CTE (Coefficient of Thermal Expansion) mismatches with the copper wire bonds that can eventually lead to device failures during thermal cycling. Despite the difficult problems associated with the changeover to copper bonding wire, there are billions of copper wire bonded devices delivered annually to customers. It is noteworthy that Texas Instruments announced in October of 2014 that they are shipping microcircuits containing copper wire bonds for safety critical automotive applications

  16. The Yin and Yang of copper during infection.

    PubMed

    Besold, Angelique N; Culbertson, Edward M; Culotta, Valeria C

    2016-04-01

    Copper is an essential micronutrient for both pathogens and the animal hosts they infect. However, copper can also be toxic in cells due to its redox properties and ability to disrupt active sites of metalloproteins, such as Fe-S enzymes. Through these toxic properties, copper is an effective antimicrobial agent and an emerging concept in innate immunity is that the animal host intentionally exploits copper toxicity in antimicrobial weaponry. In particular, macrophages can attack invading microbes with high copper and this metal is also elevated at sites of lung infection. In addition, copper levels in serum rise during infection with a wide array of pathogens. To defend against this toxic copper, the microbial intruder is equipped with a battery of copper detoxification defenses that promote survival in the host, including copper exporting ATPases and copper binding metallothioneins. However, it is important to remember that copper is also an essential nutrient for microbial pathogens and serves as important cofactor for enzymes such as cytochrome c oxidase for respiration, superoxide dismutase for anti-oxidant defense and multi-copper oxidases that act on metals and organic substrates. We therefore posit that the animal host can also thwart pathogen growth by limiting their copper nutrients, similar to the well-documented nutritional immunity effects for starving microbes of essential zinc, manganese and iron micronutrients. This review provides both sides of the copper story and evaluates how the host can exploit either copper-the-toxin or copper-the-nutrient in antimicrobial tactics at the host-pathogen battleground.

  17. Graphene-protected copper and silver plasmonics.

    PubMed

    Kravets, V G; Jalil, R; Kim, Y-J; Ansell, D; Aznakayeva, D E; Thackray, B; Britnell, L; Belle, B D; Withers, F; Radko, I P; Han, Z; Bozhevolnyi, S I; Novoselov, K S; Geim, A K; Grigorenko, A N

    2014-07-01

    Plasmonics has established itself as a branch of physics which promises to revolutionize data processing, improve photovoltaics, and increase sensitivity of bio-detection. A widespread use of plasmonic devices is notably hindered by high losses and the absence of stable and inexpensive metal films suitable for plasmonic applications. To this end, there has been a continuous search for alternative plasmonic materials that are also compatible with complementary metal oxide semiconductor technology. Here we show that copper and silver protected by graphene are viable candidates. Copper films covered with one to a few graphene layers show excellent plasmonic characteristics. They can be used to fabricate plasmonic devices and survive for at least a year, even in wet and corroding conditions. As a proof of concept, we use the graphene-protected copper to demonstrate dielectric loaded plasmonic waveguides and test sensitivity of surface plasmon resonances. Our results are likely to initiate wide use of graphene-protected plasmonics.

  18. Cascade collapse in copper and nickel

    SciTech Connect

    Vetrano, J.S.; Robertson, I.M.; Averback, R.S. . Dept. of Materials Science and Engineering); Kirk, M.A. )

    1990-04-01

    In-situ TEM studies of the development of the damage structure produced by heavy ion irradiations have been performed in copper and nickel to investigate the possibility that melting occurs in local regions within displacement cascades. These experiments reveal that as the ion dose increases additional loops form from isolated displacement cascades, but more surprisingly some fo the pre-existing loops are annihilated, change position, size and/or Burgers vector. It was also found that the probability for loop formation and the defect image size are greater in copper than in nickel even at temperatures well below stage 3. It will be demonstrated that these observations provide supporting evidence, albeit indirect, that local melting occurs within the cascade core. These results will be compared to the molecular dynamic computer simulations of the damage created by low energy self-ions in copper and nickel. 15 refs., 4 figs.

  19. Preliminary Model of Porphyry Copper Deposits

    USGS Publications Warehouse

    Berger, Byron R.; Ayuso, Robert A.; Wynn, Jeffrey C.; Seal, Robert R., II

    2008-01-01

    The U.S. Geological Survey (USGS) Mineral Resources Program develops mineral-deposit models for application in USGS mineral-resource assessments and other mineral resource-related activities within the USGS as well as for nongovernmental applications. Periodic updates of models are published in order to incorporate new concepts and findings on the occurrence, nature, and origin of specific mineral deposit types. This update is a preliminary model of porphyry copper deposits that begins an update process of porphyry copper models published in USGS Bulletin 1693 in 1986. This update includes a greater variety of deposit attributes than were included in the 1986 model as well as more information about each attribute. It also includes an expanded discussion of geophysical and remote sensing attributes and tools useful in resource evaluations, a summary of current theoretical concepts of porphyry copper deposit genesis, and a summary of the environmental attributes of unmined and mined deposits.

  20. Graphene-protected copper and silver plasmonics

    PubMed Central

    Kravets, V. G.; Jalil, R.; Kim, Y.-J.; Ansell, D.; Aznakayeva, D. E.; Thackray, B.; Britnell, L.; Belle, B. D.; Withers, F.; Radko, I. P.; Han, Z.; Bozhevolnyi, S. I.; Novoselov, K. S.; Geim, A. K.; Grigorenko, A. N.

    2014-01-01

    Plasmonics has established itself as a branch of physics which promises to revolutionize data processing, improve photovoltaics, and increase sensitivity of bio-detection. A widespread use of plasmonic devices is notably hindered by high losses and the absence of stable and inexpensive metal films suitable for plasmonic applications. To this end, there has been a continuous search for alternative plasmonic materials that are also compatible with complementary metal oxide semiconductor technology. Here we show that copper and silver protected by graphene are viable candidates. Copper films covered with one to a few graphene layers show excellent plasmonic characteristics. They can be used to fabricate plasmonic devices and survive for at least a year, even in wet and corroding conditions. As a proof of concept, we use the graphene-protected copper to demonstrate dielectric loaded plasmonic waveguides and test sensitivity of surface plasmon resonances. Our results are likely to initiate wide use of graphene-protected plasmonics. PMID:24980150

  1. Zinc, copper and selenium in reproduction.

    PubMed

    Bedwal, R S; Bahuguna, A

    1994-07-15

    Of the nine biological trace elements, zinc, copper and selenium are important in reproduction in males and females. Zinc content is high in the adult testis, and the prostate has a higher concentration of zinc than any other organ of the body. Zinc deficiency first impairs angiotensin converting enzyme (ACE) activity, and this in turn leads to depletion of testosterone and inhibition of spermatogenesis. Defects in spermatozoa are frequently observed in the zinc-deficient rat. Zinc is thought to help to extend the functional life span of the ejaculated spermatozoa. Zinc deficiency in the female can lead to such problems as impaired synthesis/secretion of (FSH) and (LH), abnormal ovarian development, disruption of the estrous cycle, frequent abortion, a prolonged gestation period, teratogenicity, stillbirths, difficulty in parturition, pre-eclampsia, toxemia and low birth weights of infants. The level of testosterone in the male has been suggested to play a role in the severity of copper deficiency. Copper-deficient female rats are protected against mortality due to copper deficiency, and the protection has been suggested to be provided by estrogens, since estrogens alter the subcellular distribution of copper in the liver and increase plasma copper levels by inducing ceruloplasmin synthesis. The selenium content of male gonads increases during pubertal maturation. Selenium is localized in the mitochondrial capsule protein (MCP) of the midpiece. Maximal incorporation in MCP occurs at steps 7 and 12 of spermatogenesis and uptake decreases by step 15. Selenium deficiency in females results in infertility, abortions and retention of the placenta. The newborns from a selenium-deficient mother suffer from muscular weakness, but the concentration of selenium during pregnancy does not have any effect on the weight of the baby or length of pregnancy. The selenium requirements of a pregnant and lactating mother are increased as a result of selenium transport to the fetus via

  2. Copper removal using electrosterically stabilized nanocrystalline cellulose.

    PubMed

    Sheikhi, Amir; Safari, Salman; Yang, Han; van de Ven, Theo G M

    2015-06-03

    Removal of heavy metal ions such as copper using an efficient and low-cost method with low ecological footprint is a critical process in wastewater treatment, which can be achieved in a liquid phase using nanoadsorbents such as inorganic nanoparticles. Recently, attention has turned toward developing sustainable and environmentally friendly nanoadsorbents to remove heavy metal ions from aqueous media. Electrosterically stabilized nanocrystalline cellulose (ENCC), which can be prepared from wood fibers through periodate/chlorite oxidation, has been shown to have a high charge content and colloidal stability. Here, we show that ENCC scavenges copper ions by different mechanisms depending on the ion concentration. When the Cu(II) concentration is low (C0≲200 ppm), agglomerates of starlike ENCC particles appear, which are broken into individual starlike entities by shear and Brownian motion, as evidenced by photometric dispersion analysis, dynamic light scattering, and transmission electron microscopy. On the other hand, at higher copper concentrations, the aggregate morphology changes from starlike to raftlike, which is probably due to the collapse of protruding dicarboxylic cellulose (DCC) chains and ENCC charge neutralization by copper adsorption. Such raftlike structures result from head-to-head and lateral aggregation of neutralized ENCCs as confirmed by transmission electron microscopy. As opposed to starlike aggregates, the raftlike structures grow gradually and are prone to sedimentation at copper concentrations C0≳500 ppm, which eliminates a costly separation step in wastewater treatment processes. Moreover, a copper removal capacity of ∼185 mg g(-1) was achieved thanks to the highly charged DCC polyanions protruding from ENCC. These properties along with the biorenewability make ENCC a promising candidate for wastewater treatment, in which fast, facile, and low-cost removal of heavy metal ions is desired most.

  3. Human copper transporter 2 is localized in late endosomes and lysosomes and facilitates cellular copper uptake

    PubMed Central

    vandenBerghe, Peter V. E.; Folmer, Dineke E.; Malingré, Helga E. M.; vanBeurden, Ellen; Klomp, Adriana E. M.; vandeSluis, Bart; Merkx, Maarten; Berger, Ruud; Klomp, Leo W. J.

    2007-01-01

    High-affinity cellular copper uptake is mediated by the CTR (copper transporter) 1 family of proteins. The highly homologous hCTR (human CTR) 2 protein has been identified, but its function in copper uptake is currently unknown. To characterize the role of hCTR2 in copper homoeostasis, epitope-tagged hCTR2 was transiently expressed in different cell lines. hCTR2–vsvG (vesicular-stomatitis-virus glycoprotein) predominantly migrated as a 17 kDa protein after imunoblot analysis, consistent with its predicted molecular mass. Chemical cross-linking resulted in the detection of higher-molecular-mass complexes containing hCTR2–vsvG. Furthermore, hCTR2–vsvG was co-immunoprecipitated with hCTR2–FLAG, suggesting that hCTR2 can form multimers, like hCTR1. Transiently transfected hCTR2–eGFP (enhanced green fluorescent protein) was localized exclusively to late endosomes and lysosomes, and was not detected at the plasma membrane. To functionally address the role of hCTR2 in copper metabolism, a novel transcription-based copper sensor was developed. This MRE (metal-responsive element)–luciferase reporter contained four MREs from the mouse metallothionein 1A promoter upstream of the firefly luciferase open reading frame. Thus the MRE–luciferase reporter measured bioavailable cytosolic copper. Expression of hCTR1 resulted in strong activation of the reporter, with maximal induction at 1 μM CuCl2, consistent with the Km of hCTR1. Interestingly, expression of hCTR2 significantly induced MRE–luciferase reporter activation in a copper-dependent manner at 40 and 100 μM CuCl2. Taken together, these results identify hCTR2 as an oligomeric membrane protein localized in lysosomes, which stimulates copper delivery to the cytosol of human cells at relatively high copper concentrations. This work suggests a role for endosomal and lysosomal copper pools in the maintenance of cellular copper homoeostasis. PMID:17617060

  4. Studies on copper alloys containing chromium on the copper side phase diagram

    NASA Technical Reports Server (NTRS)

    Doi, T.

    1984-01-01

    Specimens were prepared from vacuum melted alloys of high purity vacuum melted copper and electrolytic chromium. The liquidus and eutectic point were determined by thermal analysis. The eutectic temperature is 1974.8 F and its composition is 1.28 wt% of chromium. The determination of solid solubility of chromium in copper was made by microscopic observation and electrical resistivity measurement. The solubility of chromium in solid copper is 0.6 wt% at 1050 F, 0.4 wt% at 1000 F, 0.25 wt% at 950 F, 0.17 wt% at 900 F, and 0.30 wt% at 840 F.

  5. Acquisition of dietary copper: a role for anion transporters in intestinal apical copper uptake.

    PubMed

    Zimnicka, Adriana M; Ivy, Kristin; Kaplan, Jack H

    2011-03-01

    Copper is an essential micronutrient in humans and is required for a wide range of physiological processes, including neurotransmitter biosynthesis, oxidative metabolism, protection against reactive oxygen species, and angiogenesis. The first step in the acquisition of dietary copper is absorption from the intestinal lumen. The major human high-affinity copper uptake protein, human copper transporter hCTR1, was recently shown to be at the basolateral or blood side of both intestinal and renal epithelial cell lines and thus does not play a direct role in this initial step. We sought to functionally identify the major transport pathways available for the absorption of dietary copper across the apical intestinal membrane using Caco2 cells, a well-established model for human enterocytes. The initial rate of apical copper uptake into confluent monolayers of Caco2 cells is greatly elevated if amino acids and serum proteins are removed from the growth media. Uptake from buffered saline solutions at neutral pH (but not at lower pH) is inhibited by either d- or l-histidine, unaltered by the removal of sodium ions, and inhibited by ∼90% when chloride ions are replaced by gluconate or sulfate. Chloride-dependent copper uptake occurs with Cu(II) or Cu(I), although Cu(I) uptake is not inhibited by histidine, nor by silver ions. A well-characterized inhibitor of anion exchange systems, DIDS, inhibited apical copper uptake by 60-70%, while the addition of Mn(II) or Fe(II), competitive substrates for the divalent metal transporter DMT1, had no effect on copper uptake. We propose that anion exchangers play an unexpected role in copper absorption, utilizing copper-chloride complexes as pseudo-substrates. This pathway is also observed in mouse embryonic fibroblasts, human embryonic kidney cells, and Cos-7 cells. The special environment of low pH, low concentration of protein, and protonation of amino acids in the early intestinal lumen make this pathway especially important in

  6. Mechanism of copper selenide growth on copper-oxide selenium system

    NASA Astrophysics Data System (ADS)

    Ishikawa, Y.; Kido, O.; Kimura, Y.; Kurumada, M.; Suzuki, H.; Saito, Y.; Kaito, C.

    2004-01-01

    Transmission electron microscopy was used to study spontaneous copper selenide formation on Cu particles covered with an oxide layer. Even if the copper particle surface was covered with a Cu 2O layer, selenides were formed by diffusion through the metal oxide layer. For a particle size less than 50 nm, selenide was formed in Cu particles by the diffusion of Se atoms passing through the Cu 2O layer. For particles larger than 100 nm in size, selenide was formed in Se film. It was also found that the thickness of the Cu 2O layer on the surface of Cu particle accelerated diffusion of Se atoms to the copper particle.

  7. Copper uptake and regulation in a copper-tolerant decapod Cambarus bartoni (Fabricius)

    SciTech Connect

    Zia, S.; Alikhan, M.A.

    1989-01-01

    Large amounts of acid forming sulfur dioxide, and heavy metals including copper, are continuously being released into the environment by mining and smelting operation at Sudbury, Ontario, Canada. Consequently, a number of lakes in this region have become acidic and metal stressed. In the current study the uptake and accumulation of copper by various tissues of a copper-tolerant crayfish, Cambarus bartoni, were monitored in the laboratory to ascertain the dynamic nature (i.e., the pattern in time) of responses of crayfish to increased levels of these two metals in the water.

  8. Synthesis of copper monolayer and particles at aqueous organic interface

    NASA Astrophysics Data System (ADS)

    Yang, Jian-guang; Yang, Sheng-hai; Okamoto, Takeshi; Bessho, Takeshi; Satake, Shigeru; Ichino, Ryoichi; Okido, Masazumi

    2006-12-01

    Using aqueous-organic interface (water-oleic acid) reduction of Cu 2+ by ascorbic acid, hydrophobic copper monolayer and copper particles have been prepared and characterized. The resultant monolayer could be transferred from the interface onto solid substrate or be dissolved to yield an organosol and copper nanoparticles.

  9. Tantalum-copper alloy and method for making

    DOEpatents

    Schmidt, F.A.; Verhoeven, J.D.; Gibson, E.D.

    1983-06-01

    A tantalum-copper alloy can be made by preparing a consumable electrode consisting of an elongated copper billet containing at least two spaced apart tantalum rods extending longitudinally the length of the billet. The electrode is placed in a dc arc furnace and melted under conditions which co-melt the copper and tantalum to form the alloy.

  10. Tantalum-copper alloy and method for making

    DOEpatents

    Schmidt, Frederick A.; Verhoeven, John D.; Gibson, Edwin D.

    1984-11-06

    A tantalum-copper alloy can be made by preparing a consumable electrode consisting of an elongated copper billet containing at least two spaced apart tantalum rods extending longitudinally the length of the billet. The electrode is placed in a dc arc furnace and melted under conditions which co-melt the copper and tantalum to form the alloy.

  11. 21 CFR 73.125 - Sodium copper chlorophyllin.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Sodium copper chlorophyllin. 73.125 Section 73.125... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.125 Sodium copper chlorophyllin. (a) Identity. (1) The color additive sodium copper chlorophyllin is a green to black powder prepared from chlorophyll...

  12. 21 CFR 73.125 - Sodium copper chlorophyllin.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Sodium copper chlorophyllin. 73.125 Section 73.125... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.125 Sodium copper chlorophyllin. (a) Identity. (1) The color additive sodium copper chlorophyllin is a green to black powder prepared from chlorophyll...

  13. 21 CFR 73.125 - Sodium copper chlorophyllin.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Sodium copper chlorophyllin. 73.125 Section 73.125... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.125 Sodium copper chlorophyllin. (a) Identity. (1) The color additive sodium copper chlorophyllin is a green to black powder prepared from chlorophyll...

  14. 40 CFR 721.10391 - Copper gallium indium selenide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Copper gallium indium selenide. 721... Substances § 721.10391 Copper gallium indium selenide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as copper gallium indium selenide (PMN...

  15. 40 CFR 721.10391 - Copper gallium indium selenide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Copper gallium indium selenide. 721... Substances § 721.10391 Copper gallium indium selenide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as copper gallium indium selenide (PMN...

  16. 40 CFR 721.10391 - Copper gallium indium selenide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Copper gallium indium selenide. 721... Substances § 721.10391 Copper gallium indium selenide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as copper gallium indium selenide (PMN...

  17. THE SOLUBILITY AND SURFACE CHEMISTRY OF FRESHLY PRECIPITATED COPPER SOLIDS

    EPA Science Inventory

    Since the implementation of the United States Environmental Protection Agency’s Lead and Copper Rule (LCR) in 1991, a great deal of research has been conducted on copper corrosion and the leaching of copper from materials in drinking water distribution systems. While important p...

  18. Proline improves copper tolerance in chickpea (Cicer arietinum).

    PubMed

    Singh, Vijeta; Bhatt, Indu; Aggarwal, Anjali; Tripathi, Bhumi Nath; Munjal, Ashok Kumar; Sharma, Vinay

    2010-09-01

    The present study suggests the involvement of proline in copper tolerance of four genotypes of Cicer arietinum (chickpea). Based on the data of tolerance index and lipid peroxidation, the order for copper tolerance was as follows: RSG 888 > CSG 144 > CSG 104 > RSG 44 in the selected genotypes. The basis of differential copper tolerance in chickpea genotypes was characterized by analyzing, antioxidant enzymes (superoxide dismutase, ascorbated peroxidase and catalase), phytochelatins, copper uptake, and proline accumulation. Chickpea genotypes showed stimulated superoxide dismutase activity at all tested concentrations of copper, but H(2)O(2) decomposing enzymes especially; ascorbate peroxidase did not increase with 25 and 50 microM copper treatments. Catalase activity, however, increased at lower copper concentrations but failed to stimulate at 50 microM copper. Such divergence in responses of these enzymes minimizes their importance in protecting chickpea against copper stress. The sensitive genotypes showed greater enhancement of phytochelatins than that of tolerant genotypes. Hence, the possibility of phytochelatins in improving copper tolerance in the test plant is also excluded. Interestingly, the order of proline accumulation in the chickpea genotypes (RSG 888 > CSG 144 > CSG 104 > RSG 44) was exactly similar to the order of copper tolerance. Based on hyperaccumulation of proline in tolerant genotype (RSG 44) and the reduction and improvement of lipid peroxidation and tolerance index, respectively, by proline pretreatment, we conclude that hyperaccumulation of proline improves the copper tolerance in chickpea.

  19. LONG-TERM IMPACTS OF ORTHOPHOSPHATE TREATMENT ON COPPER

    EPA Science Inventory

    Laboratory, pilot, and field data collected support the theoretical "cupric hydroxide" copper solubility model. For the short time frames inherent in laboratory and pilot studies of copper solubility and in initial field monitoring for the LCR from Tier 1 soldered copper sites, c...

  20. LONG-TERM IMPACTS OF ORTHOPHOSPHATE TREATMENT ON COPPER LEVELS

    EPA Science Inventory

    Laboratory, pilot, and field data collected support the theoretical “cupric hydroxide” copper solubility model. For the short time frames inherent in laboratory and pilot studies of copper solubility and in initial field monitoring for the LCR from Tier 1 soldered copper sites,...

  1. Release of Micronized Copper Particles from Pressure Treated Wood Products

    EPA Science Inventory

    Micronized copper pressure treated lumber (PTL) has recently been introduced to the consumer market as a replacement for ionized copper PTL. The presence of particulate rather than aqueous copper raises concerns about the exposure of humans as well as the environment to the parti...

  2. Copper: Its Environmental Impacts. AIO Red Paper #22.

    ERIC Educational Resources Information Center

    Boutis, Elizabeth; Jantzen, Jonathan Landis, Ed.

    Although copper is a widespread and useful metal, the process of mining and refining copper can have severe detrimental impacts on humans, plants, and animals. The most serious impacts from copper production are the release of sulphur dioxide and other air pollutants and the poisoning of water supplies. These impacts occur in both the mining and…

  3. 21 CFR 73.2120 - Disodium EDTA-copper.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Disodium EDTA-copper. 73.2120 Section 73.2120 Food... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2120 Disodium EDTA-copper. (a) Identity. The color additive disodium EDTA-copper is disodium ] (4-)-N,N′,O,O′,O N,O N′] cuprate (2-)....

  4. 49 CFR 192.377 - Service lines: Copper.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Service lines: Copper. 192.377 Section 192.377 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... § 192.377 Service lines: Copper. Each copper service line installed within a building must be...

  5. 21 CFR 73.2120 - Disodium EDTA-copper.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Disodium EDTA-copper. 73.2120 Section 73.2120 Food... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2120 Disodium EDTA-copper. (a) Identity. The color additive disodium EDTA-copper is disodium ] (4-)-N,N′,O,O′,O N,O N′] cuprate (2-)....

  6. 21 CFR 73.2120 - Disodium EDTA-copper.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Disodium EDTA-copper. 73.2120 Section 73.2120 Food... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2120 Disodium EDTA-copper. (a) Identity. The color additive disodium EDTA-copper is disodium ] (4-)-N,N′,O,O′,O N,O N′] cuprate (2-)....

  7. 49 CFR 192.377 - Service lines: Copper.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Service lines: Copper. 192.377 Section 192.377 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... § 192.377 Service lines: Copper. Each copper service line installed within a building must be...

  8. 21 CFR 74.3045 - [Phthalocyaninato(2-)] copper.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 1 2014-04-01 2014-04-01 false copper. 74.3045 Section 74.3045 Food and Drugs... ADDITIVES SUBJECT TO CERTIFICATION Medical Devices § 74.3045 copper. (a) Identity. The color additive is copper (CAS Reg. No. 147-14-8) having the structure shown in Colour Index No. 74160. (b)...

  9. 49 CFR 192.377 - Service lines: Copper.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Service lines: Copper. 192.377 Section 192.377 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... § 192.377 Service lines: Copper. Each copper service line installed within a building must be...

  10. 21 CFR 74.3045 - [Phthalocyaninato(2-)] copper.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false copper. 74.3045 Section 74.3045 Food and Drugs... ADDITIVES SUBJECT TO CERTIFICATION Medical Devices § 74.3045 copper. (a) Identity. The color additive is copper (CAS Reg. No. 147-14-8) having the structure shown in Colour Index No. 74160. (b)...

  11. 21 CFR 73.2120 - Disodium EDTA-copper.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Disodium EDTA-copper. 73.2120 Section 73.2120 Food... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2120 Disodium EDTA-copper. (a) Identity. The color additive disodium EDTA-copper is disodium ] (4-)-N,N′,O,O′,O N,O N′] cuprate (2-)....

  12. 21 CFR 74.3045 - [Phthalocyaninato(2-)] copper.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false copper. 74.3045 Section 74.3045 Food and Drugs... ADDITIVES SUBJECT TO CERTIFICATION Medical Devices § 74.3045 copper. (a) Identity. The color additive is copper (CAS Reg. No. 147-14-8) having the structure shown in Colour Index No. 74160. (b)...

  13. 21 CFR 74.3045 - [Phthalocyaninato(2-)] copper.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false copper. 74.3045 Section 74.3045 Food and Drugs... ADDITIVES SUBJECT TO CERTIFICATION Medical Devices § 74.3045 copper. (a) Identity. The color additive is copper (CAS Reg. No. 147-14-8) having the structure shown in Colour Index No. 74160. (b)...

  14. 49 CFR 192.377 - Service lines: Copper.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Service lines: Copper. 192.377 Section 192.377 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... § 192.377 Service lines: Copper. Each copper service line installed within a building must be...

  15. 49 CFR 192.377 - Service lines: Copper.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Service lines: Copper. 192.377 Section 192.377 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... § 192.377 Service lines: Copper. Each copper service line installed within a building must be...

  16. Luminescent Colloidal Semiconductor Nanocrystals Containing Copper: Synthesis, Photophysics, and Applications.

    PubMed

    Knowles, Kathryn E; Hartstein, Kimberly H; Kilburn, Troy B; Marchioro, Arianna; Nelson, Heidi D; Whitham, Patrick J; Gamelin, Daniel R

    2016-09-28

    Copper-doped semiconductors are classic phosphor materials that have been used in a variety of applications for many decades. Colloidal copper-doped semiconductor nanocrystals have recently attracted a great deal of interest because they combine the solution processability and spectral tunability of colloidal nanocrystals with the unique photoluminescence properties of copper-doped semiconductor phosphors. Although ternary and quaternary semiconductors containing copper, such as CuInS2 and Cu2ZnSnS4, have been studied primarily in the context of their photovoltaic applications, when synthesized as colloidal nanocrystals, these materials have photoluminescence properties that are remarkably similar to those of copper-doped semiconductor nanocrystals. This review focuses on the luminescent properties of colloidal copper-doped, copper-based, and related copper-containing semiconductor nanocrystals. Fundamental investigations into the luminescence of copper-containing colloidal nanocrystals are reviewed in the context of the well-established luminescence mechanisms of bulk copper-doped semiconductors and copper(I) molecular coordination complexes. The use of colloidal copper-containing nanocrystals in applications that take advantage of their luminescent properties, such as bioimaging, solid-state lighting, and luminescent solar concentrators, is also discussed.

  17. Long-Term Effects of Orthophosphate Treatment on Copper Concentration

    EPA Science Inventory

    Laboratory, pilot, and field data collected support the theoretical “cupric hydroxide” copper solubility model. For the short time frames inherent in laboratory and pilot studies of copper solubility, and in initial field monitoring for the LCR from Tier 1 soldered copper sites,...

  18. Copper and endogenous mediators of estradiol action.

    PubMed

    Fishman, J H; Fishman, J

    1988-04-29

    Divalent copper increases by severalfold specific estradiol binding in rat uterine cytosol at 37 degrees C. Two endogenous substances have now been isolated from the cytosol one of which sharply inhibits the copper effect while the other sharply promotes it. The inhibitor is thermostable, it is adsorbed by dextran coated charcoal and elutes from Sephadex columns with water. The promoter is thermolabile at 60 degrees C, it is not readily adsorbed by the charcoal and elutes from Sephadex columns with KCl. The two substances are thought to be mediators of estradiol action.

  19. Photoluminescence Study of Copper Selenide Thin Films

    NASA Astrophysics Data System (ADS)

    Urmila, K. S.; Asokan, T. Namitha; Pradeep, B.

    2011-10-01

    Thin films of Copper Selenide of composition of composition Cu7Se4 with thickness 350 nm are deposited on glass substrate at a temperature of 498 K±5 K and pressure of 10-5 mbar using reactive evaporation, a variant of Gunther's three temperature method with high purity Copper (99.999%) and Selenium (99.99%) as the elemental starting material. The deposited film is characterized structurally using X-ray Diffraction. The structural parameters such as lattice constant, particle size, dislocation density; number of crystallites per unit area and strain in the film are evaluated. Photoluminescence of the film is analyzed at room temperature using Fluoro Max-3 Spectrofluorometer.

  20. Forensic Applications Of Copper Laser Technology

    NASA Astrophysics Data System (ADS)

    German, Edward R.

    1987-04-01

    Copper vapor lasers are being used in forensic applications at more than thirty regional, state and national level forensic science laboratories (crime labs) in the United States, Israel and Japan. These high gain lasing medium systems provide desirable operational and maintenance features. The green line produced by copper vapor lasers allows use of latent fingerprint inherent and chemically induced luminescence techniques developed for argon ion lasers. The yellow line has developed latent fingerprints which would not luminesce at blue-green wavelengths, and is better suited for some forensic examinations such as ink differentiation involving forgeries and document alterations.

  1. Mineral resource of the month: copper

    USGS Publications Warehouse

    ,

    2011-01-01

    The article provides information on copper and its various uses. It was the first metal used by humans and is considered as one of the materials that played an important role in the development of civilization. It is a major industrial metal because of its low cost, availability, electrical conductivity, high ductility and thermal conductivity. Copper has long been used in the circuitry of electronics and the distribution of electricity and is now being used in silicon-based computer chips, solar and wind power generation, and coinage.

  2. Copper toxicity in the crab, Scylla serrata, copper levels in tissues and regulation after exposure to a copper-rich medium

    SciTech Connect

    Arumugam, M.; Ravindranath, M.H.

    1987-10-01

    In the decapod crustaceans copper is distributed in various tissues. In these animals the tissue copper generally exists in four forms; ionic, bound to proteins, lipids and membrane. In the estuarine crab Scylla serrata, the haemolymph copper exists only in association with proteins, whereas in the hepatopancreas it exists in all the four forms and in gills it exists in all the forms except in combination with lipids. Although food is the major source of copper in decapod crustaceans evidence indicate that copper may be directly obtained from the environment. It was postulated earlier that in Scylla serrata the haemolymph and hepatopancreas may be involved in copper regulation. In the present work the authors have studied the nature and levels of copper in different tissues after exposing the crabs to copper-rich medium. The results indicate the relative importance of various tissues in accumulation an the possible mechanisms of regulation of the environmental copper. Besides, as a pre-requisite for studies of this kind, the toxic levels for different forms of copper were estimated since the form of toxicant is known to influence the toxicity to the decapod crustaceans.

  3. Copper(I) and copper(II) uranyl heterometallic hybrid materials.

    PubMed

    Weng, Zhehui; Zhang, Zhi-hui; Olds, Travis; Sterniczuk, Marcin; Burns, Peter C

    2014-08-04

    Two copper-uranium heterometallic compounds, [(UO2)3Cu(II)O2(C6NO2)5] (1) and [(UO2)Cu(I)(C6NO2)3] (2), have been synthesized by the reaction of uranyl acetate with copper salts in the presence of isonicotinic acid. Both compounds have been characterized by single-crystal X-ray diffraction, IR, Raman, and UV-vis spectroscopy. In compound 1, interactions between copper and uranium centers occur and result in a three-dimensional pillar layered structure. Compound 1 is also the first example of a heterometallic uranyl organic framework with a trinuclear U3O18 building block. Compound 2 is the first uranyl organic framework that contains monovalent copper, which arises from the reaction of Cu(II) chloride and is assumed to be due to the oxidation of chloride at low pH.

  4. 21 CFR 73.1125 - Potassium sodium copper chloropyhllin (chlorophyllin-copper complex).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... additive potassium sodium copper chlorophyllin is a green to black powder obtained from chlorophyll by... of the chlorophyll is dehydrated alfalfa. (2) Color additive mixtures for drug use made...

  5. Enrichment of copper and recycling of cyanide from copper-cyanide waste by solvent extraction

    NASA Astrophysics Data System (ADS)

    Gao, Teng-yue; Liu, Kui-ren; Han, Qing; Xu, Bin-shi

    2016-11-01

    The enrichment of copper from copper-cyanide wastewater by solvent extraction was investigated using a quaternary ammonium salt as an extractant. The influences of important parameters, e.g., organic-phase components, aqueous pH values, temperature, inorganic anion impurities, CN/Cu molar ratio, and stripping reagents, were examined systematically, and the optimal conditions were determined. The results indicated that copper was effectively concentrated from low-concentration solutions using Aliquat 336 and that the extraction efficiency increased linearly with increasing temperature. The aqueous pH value and concentrations of inorganic anion impurities only weakly affected the extraction process when varied in appropriate ranges. The CN/Cu molar ratio affected the extraction efficiency by changing the distribution of copper-cyanide complexes. The difference in gold leaching efficiency between using raffinate and fresh water was negligible.

  6. Formation of conductive copper lines by femtosecond laser irradiation of copper nitride film on plastic substrates

    SciTech Connect

    Xu, Xiaodong; Yuan, Ningyi; Qiu, Jianhua; Ding, Jianning

    2015-05-15

    In this paper, we report a simple method to form conductive copper lines by scanning a single-beam femtosecond pulse laser on a plastic substrate covered with copper nitride (Cu{sub 3}N) film. The Cu{sub 3}N films were prepared by DC magnetron sputtering in the presence of an Ar + N{sub 2} atmosphere at 100 °C. The influence of the laser power and scanning speed on the formed copper line width, surface features, and morphology was analyzed by means of optical microscopy, X-ray diffraction, non-contact 3D profilometer, and scanning electron microscopy. The experimental results demonstrate that low laser power and low scanning speed favor the formation of uniform and flat Cu lines. After process optimization, copper lines with a width less than 5 μm were obtained, which provides an attractive application prospect in the field of flexible electronic devices.

  7. Ambient Facile Synthesis of Gram-Scale Copper Selenide Nanostructures from Commercial Copper and Selenium Powder.

    PubMed

    Chen, Xin Qi; Li, Zhen; Dou, Shi Xue

    2015-06-24

    Grams of copper selenides (Cu(2-x)Se) were prepared from commercial copper and selenium powders in the presence of thiol ligands by a one-pot reaction at room temperature. The resultant copper selenides are a mixture of nanoparticles and their assembled nanosheets, and the thickness of nanosheets assembled is strongly dependent on the ratio of thiol ligand to selenium powder. The resultant Cu(2-x)Se nanostructures were treated with hydrazine solution to remove the surface ligands and then explored as a potential thermoelectric candidate in comparison with commercial copper selenide powders. The research provides a novel ambient approach for preparation of Cu(2-x)Se nanocrystallines on a large scale for various applications.

  8. Copper hazards to fish, wildlife and invertebrates: a synoptic review

    USGS Publications Warehouse

    Eisler, Ronald

    1998-01-01

    Selective review and synthesis of the technical literature on copper and copper salts in the environment and their effects primarily on fishes, birds, mammals, terrestrial and aquatic invertebrates, and other natural resources. The subtopics include copper sources and uses; chemical and biochemical properties; concentrations of copper in field collections of abiotic materials and living organisms; effects of copper deficiency; lethal and sublethal effects on terrestrial plants and invertebrates, aquatic organisms, birds and mammals, including effects on survival, growth, reproduction, behavior, metabolism, carcinogenicity, matagenicity, and teratogenicity; proposed criteria for the protection of human health and sensitive natural resources; and recommendations for additional research.

  9. Superconducting properties of evaporated copper molybdenum sulfide films

    NASA Technical Reports Server (NTRS)

    Woollam, J. A.; Chi, K. C.; Dillon, R. O.; Bunshah, R. F.; Alterovitz, S. A.

    1978-01-01

    Films of copper molybdenum sulfide were produced by coevaporation. Those that were superconducting contained only the ternary compound and free molybdenum. The range of copper content in the ternary compound was as large as that in polycrystalline material, that is, it includes either phase alone, or a mixture of the two phases of this material. This is in contrast with sputtered materials where copper concentration has been limited to a narrower range. The upper critical field and the critical current were measured as functions of external magnetic field, and found to be similar to those of sputtered copper molybdenum sulfide, when the comparison was made for samples having the same amount of copper.

  10. Biomineralization of copper: Solutions for waste remediation and biomining

    SciTech Connect

    Ashby, C.R.; Thompson, S.A.; Crusberg, T.C.

    1997-12-31

    The fungus Penicillium ochro-chloron is able to extract copper from aqueous solutions and form insoluble copper precipitates within the matrix of fungal mycelia. The formation of these complexes is probably a detoxification mechanism used by the organism to deal with the potentially lethal concentrations of heavy metals. Metal immobilization occurs external to the cells but within the mycelia when the solubility products of copper phosphate and copper oxalate are exceeded. This process may be exploited in biomining to remove and recover copper and perhaps other heavy metals that have become solubilized in pit mine lakes.

  11. Characteristics and antimicrobial activity of copper-based materials

    NASA Astrophysics Data System (ADS)

    Li, Bowen

    In this study, copper vermiculite was synthesized, and the characteristics, antimicrobial effects, and chemical stability of copper vermiculite were investigated. Two types of copper vermiculite materials, micron-sized copper vermiculite (MCV) and exfoliated copper vermiculite (MECV), are selected for this research. Since most of the functional fillers used in industry products, such as plastics, paints, rubbers, papers, and textiles prefer micron-scaled particles, micron-sized copper vermiculite was prepared by jet-milling vermiculite. Meanwhile, since the exfoliated vermiculite has very unique properties, such as high porosity, specific surface area, high aspect ratio of laminates, and low density, and has been extensively utilized as a functional additives, exfoliated copper vermiculite also was synthesized and investigated. The antibacterial efficiency of copper vermiculite was qualitatively evaluated by the diffusion methods (both liquid diffusion and solid diffusion) against the most common pathogenic species: Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Klebsiella pneumoniae (K. pneumoniae). The result showed that the release velocity of copper from copper vermiculite is very slow. However, copper vermiculite clearly has excellent antibacterial efficiency to S. aureus, K. pneumoniae and E. coli. The strongest antibacterial ability of copper vermiculite is its action on S. aureus. The antibacterial efficiency of copper vermiculite was also quantitatively evaluated by determining the reduction rate (death rate) of E. coli versus various levels of copper vermiculite. 10 ppm of copper vermiculite in solution is sufficient to reduce the cell population of E. coli, while the untreated vermiculite had no antibacterial activity. The slow release of copper revealed that the antimicrobial effect of copper vermiculite was due to the strong interactions between copper ions and bacteria cells. Exfoliated copper vermiculite has even stronger

  12. Development of copper based drugs, radiopharmaceuticals and medical materials.

    PubMed

    Szymański, Paweł; Frączek, Tomasz; Markowicz, Magdalena; Mikiciuk-Olasik, Elżbieta

    2012-12-01

    Copper is one of the most interesting elements for various biomedical applications. Copper compounds show vast array of biological actions, including anti-inflammatory, anti-proliferative, biocidal and other. It also offers a selection of radioisotopes, suitable for nuclear imaging and radiotherapy. Quick progress in nanotechnology opened new possibilities for design of copper based drugs and medical materials. To date, copper has not found many uses in medicine, but number of ongoing research, as well as preclinical and clinical studies, will most likely lead to many novel applications of copper in the near future.

  13. Effect of ultrasound on the removal of copper from the model solutions for copper electrolysis process.

    PubMed

    Farooq, Robina; Wang, Y; Lin, F; Shaukat, S F; Donaldson, J; Chouhdary, A J

    2002-07-01

    A novel combination of an ultrasonic field with electrolysis for the removal of copper is studied. In the ultrasonic field, cavitation acts as jets and agitates the solution and breaks the barrier layer between the cathode surface and the bulk of the solution, thus increases the metal deposition on the cathode surface. The results show that an ultrasonic field is successful for the removal of low copper concentrations in solution.

  14. Removal of copper from a copper sulphate solution using an ultrasonic-electrolysis process.

    PubMed

    Farooq, Robina; Wang, Y; Shaukat, S F; Donaldson, J; Chaudhary, A J

    2002-07-01

    The application of ultrasonic-electrolysis process for the removal of copper is studied. In the ultrasonic field cavitation acts as jets and agitates the solution and breaks the barrier layer between the cathode surface and the bulk of the solution. Thus increases metal deposition on the cathode surface. The results show that an ultrasonic field is successful for the removal of low copper concentrations in solution.

  15. Selective leaching process for the recovery of copper and zinc oxide from copper-containing dust.

    PubMed

    Wu, Jun-Yi; Chang, Fang-Chih; Wang, H Paul; Tsai, Ming-Jer; Ko, Chun-Han; Chen, Chih-Cheng

    2015-01-01

    The purpose of this study was to develop a resource recovery procedure for recovering copper and zinc from dust produced by copper smelting furnaces during the manufacturing of copper-alloy wires. The concentrations of copper in copper-containing dust do not meet the regulation standards defined by the Taiwan Environmental Protection Administration; therefore, such waste is classified as hazardous. In this study, the percentages of zinc and copper in the dust samples were approximately 38.4% and 2.6%, respectively. To reduce environmental damage and recover metal resources for industrial reuse, acid leaching was used to recover metals from these inorganic wastes. In the first stage, 2 N of sulphuric acid was used to leach the dust, with pH values controlled at 2.0-3.0, and a solid-to-liquid ratio of 1:10. The results indicated that zinc extraction efficiency was higher than 95%. A selective acid leaching process was then used to recover the copper content of the residue after filtration. In the second stage, an additional 1 N of sulphuric acid was added to the suspension in the selective leaching process, and the pH value was controlled at 1.5-2.0. The reagent sodium hydroxide (2 N) was used as leachate at a pH greater than 7. A zinc hydroxide compound formed during the process and was recovered after drying. The yields for zinc and copper were 86.9-93.5% and 97.0-98.9%, respectively.

  16. Relative bioavailability of copper in tribasic copper chloride to copper in copper sulfate for laying hens based on egg yolk and feather copper concentrations.

    PubMed

    Kim, J W; Kim, J H; Shin, J E; Kil, D Y

    2016-07-01

    This experiment was conducted to determine the relative bioavailability (RBV) of Cu in tribasic copper chloride (TBCC) to Cu in copper sulfate (monohydrate form; CuSO4·H2O) for layer diets based on egg yolk and feather Cu concentrations. A total of 252, 72-wk-old Hy-Line Brown laying hens were allotted to 1 of 7 treatments with 6 replicates consisting of 6 hens per replicate in a completely randomized design. Hens were fed corn-soybean meal-based basal diets supplemented with 0 (basal), 100, 200, or 300 mg/kg Cu from CuSO4 or TBCC for 4 wk. Results indicated that egg production, egg weight, and egg mass were not affected by dietary treatments. However, increasing inclusion levels of Cu in diets from CuSO4 decreased (P < 0.05) feed conversion ratio (FCR), whereas increasing inclusion levels of Cu in diets from TBCC did not affect FCR, indicating significant interaction (P < 0.05). Increasing inclusion levels of Cu from TBCC or CuSO4 increased (P < 0.05) Cu concentrations of egg yolk and feathers. Feather Cu concentrations were greater (P < 0.01) for hens fed diets containing CuSO4 than for hens fed diets containing TBCC. The values for the RBV of Cu in TBCC to Cu in CuSO4 based on log10 transformed egg yolk and feather Cu concentrations were 107.4% and 69.5%, respectively. These values for the RBV of Cu in TBCC did not differ from Cu in CuSO4 (100%). The RBV measured in egg yolk did not differ from the RBV measured in feather. In conclusion, the RBV of Cu in TBCC to Cu in CuSO4 can be determined using Cu concentrations of egg yolk and feathers although the values depend largely on target tissues of laying hens. For a practical application, however, the RBV value of Cu in TBCC to Cu in CuSO4 could be 88.5% when the RBV values determined using egg yolk and feather Cu concentrations were averaged.

  17. Alternative Anode Reaction for Copper Electrowinning

    SciTech Connect

    Not Available

    2005-07-01

    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 the same quantity of copper. This alternative anode reaction, which oxidizes ferric ions to ferrous, with subsequent reduction back to ferric using sulfur dioxide, was demonstrated to be technically and operationally feasible. However, pure sulfur dioxide was determined to be prohibitively expensive and use of a sulfur burner, producing 12% SO{sub 2}, was deemed a viable alternative. This alternate, sulfur-burning process requires a sulfur burner, waste heat boiler, quench tower, and reaction towers. The electrolyte containing absorbed SO{sub 2} passes through activated carbon to regenerate the ferrous ion. Because this reaction produces sulfuric acid, excess acid removal by ion exchange is necessary and produces a low concentration acid suitable for leaching oxide copper minerals. If sulfide minerals are to be leached or the acid unneeded on site, hydrogen was demonstrated to be a potential reductant. Preliminary economics indicate that the process would only be viable if significant credits could be realized for electrical power produced by the sulfur burner and for acid if used for leaching of oxidized copper minerals on site.

  18. 21 CFR 582.5260 - Copper gluconate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Copper gluconate. 582.5260 Section 582.5260 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  19. 21 CFR 582.5260 - Copper gluconate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Copper gluconate. 582.5260 Section 582.5260 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  20. 21 CFR 582.5260 - Copper gluconate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Copper gluconate. 582.5260 Section 582.5260 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  1. 21 CFR 582.5260 - Copper gluconate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Copper gluconate. 582.5260 Section 582.5260 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  2. 21 CFR 582.5260 - Copper gluconate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Copper gluconate. 582.5260 Section 582.5260 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  3. Simplified Fabrication of Helical Copper Antennas

    NASA Technical Reports Server (NTRS)

    Petro, Andrew

    2006-01-01

    A simplified technique has been devised for fabricating helical antennas for use in experiments on radio-frequency generation and acceleration of plasmas. These antennas are typically made of copper (for electrical conductivity) and must have a specific helical shape and precise diameter.

  4. Minnows get columnaris too; copper sulfate works!

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was conducted to compare the therapeutic effects of copper sulfate (CuSO4), when delivered in either a flow-through or static system, on the survival of golden shiner (Notemigonus crysoleucas; Fig. 1A) and fathead minnow (Pimephales promelas; Fig. 1B) infected with Flavobacterium columnare (...

  5. A Simulator for Copper Ore Leaching

    SciTech Connect

    Travis, B.

    1999-05-14

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). Copper is a strategic metal and the nation needs a secure supply both for industrial use and military needs. However, demand is growing worldwide and is outstripping the ability of the mining industry to keep up. Improved recovery methods are critically needed to maintain the balance of supply and demand. The goal of any process design should be to increase the amount of copper recovered, control movement of acid and other environmentally harmful chemicals, and reduce energy requirements. To achieve these ends, several improvements in current technology are required, the most important of which is a better understanding of, and the ability to quantify, how fluids move through heterogeneous materials in a complex chemical environment. The goal of this project is create a new modeling capability that couples hydrology with copper leaching chemistry . once the model has been verified and validated, we can apply the model to specific problems associated with heap leaching (flow channeling due to non-uniformities in heap structure, precipitation/dissolution reactions, and bacterial action), to understand the causes of inefficiencies, and to design better recovery systems. We also intend to work with representatives of the copper mining industry to write a coordinated plan for further model development and application that will provide economic benefits to the industry and the nation.

  6. Portal copper transport in rats by albumin

    SciTech Connect

    Gordon, D.T.; Leinart, A.S.; Cousins, R.J.

    1987-03-01

    The distribution of newly absorbed copper among serum proteins obtained from the portal circulation of rats was examined by conventional and high-performance gel filtration chromatography, affinity chromatography, and Western blotting. Within 10-30 min after being administered by gavage or directly into the intestine, /sup 67/Cu and /sup 64/Cu, respectively, were recovered in the albumin fraction. By 8 h after administration of the radionuclides, virtually all of the radioactivity was found with ceruloplasmin. Affigel blue fractionation and subsequent Superose-6 chromatography further demonstrated that all of the copper in the albumin-containing fractions was in fact bound to this protein rather than high molecular weight moieties. Vascular perfusion of the isolated rat intestine, where /sup 64/Cu was infused into the lumen, showed that newly absorbed /sup 64/Cu in the vascular perfusate collected from the cannulated portal vein was associated with albumin. Uptake of radioactivity by isolated rat liver parenchymal cells from medium containing rat serum with /sup 67/Cu bound to albumin was demonstrated. In vitro binding of /sup 64/Cu to serum proteins that were transferred to nitrocellulose by Western blotting techniques showed that albumin is essentially the only protein that binds appreciable amounts of copper. The data suggest that albumin is the plasma protein that is responsible for the initial transport of copper after absorption.

  7. Microvascular effects of copper deficiency in rats

    SciTech Connect

    Schuschke, D.A.; Saari, J.T.; Ackermann, D.M.; Miller, F.N. )

    1989-02-15

    We have studied the microcirculatory responses in copper deficient rats using the rat cremaster muscle preparation. Male Sprague-Dawley rats were fed either a copper supplemented diet (CuS, 5 ppm) or a copper deficient diet (CuD, O ppm) for five weeks prior to experimentation. The rats (240-300g) were anesthetized with pentobarbital and the cremaster (with intact nerve and blood supply) were spread in a tissue bath filled with krebs solution. In vivo television microscopy was used to observe the microcirculation. Fluorescein isothiocyanate tagged to bovine serum albumin (FITC-BSA) was injected i.a. 30 min prior to the start of experimentation. In the CuS animals photoactivation of the intravascular FITC-BSA caused significant platelet aggregation and reduction in red blood cell column diameter (RBCCD) by 30 min and stasis of flow by 60 min. In CuD animals there was no reduction in RBCCD and only minor platelet aggregation after 60 min of photoactivation. Topical administration of compound 48/80 (1.0 and 10.0 {mu}g/ml) induced a significantly greater macromolecular leakage (increased interstitial fluorescence of FITC-BSA) in the CuD animals than in the control, CuS animals. These results suggest that copper deficiency results in marked alterations of the regulatory mechanisms governing thrombosis and inflammation.

  8. [Silicosis among former copper mine workers].

    PubMed

    de Freitas Luz, Fernanda; Stüker, Volmar Carlos; Trevisan, Marcelo Bradelli; Cirino, Silvia Letícia Merceo Bacchi

    2011-08-01

    There is a dearth of Brazilian studies analyzing the effect of ongoing exposure to silica among former copper mine workers, as radiographic readings for silicosis have received widespread medical attention. The scope of this study is to investigate the clinical and radiological manifestations of silicosis among former copper mine workers. A sample of 100 former copper miners had their clinical and occupational histories recorded and underwent chest radiography in a cross-sectional study that included personal interviews in which their age, sex and time worked in copper extraction were recorded. Patients with recent chest X-Rays brought them with them, or they signed a term of consent and X-Rays were taken and analyzed by the radiologist using the Student t Test and Pearson test. Among the 100 miners, 35% had silicosis, 11% had conditions other than silicosis, such as tuberculosis, emphysema, chronic pulmonary obstructive disease, and 54% had no pulmonary lesions. The high incidence of silicosis reinforces the recommendation that exposure should be halted as soon as an X-ray detects the condition.

  9. COPPER PITTING CORROSION: A CASE STUDY

    EPA Science Inventory

    Localized or pitting corrosion of copper pipes used in household drinking-water plumbing is a problem for many water utilities and their customers. Extreme attack can lead to pinhole water leaks that may result in water damage, mold growth, and costly repairs. Water quality has b...

  10. 21 CFR 73.1647 - Copper powder.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... good manufacturing practice. (d) Labeling. The color additive and any mixture prepared therefrom... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1647 Copper powder. (a) Identity. (1) The color additive... contains small amounts of stearic or oleic acid as lubricants. (2) Color additive mixtures for drug...

  11. THE CHEMISTRY OF NEW COPPER PLUMBING

    EPA Science Inventory

    The presence of sulfate, bicarbonate and orthophosphate can change the type of solid present in systems containing cupric ion or cupric hydroxide solids. In some cases, a short term reduction in copper solubility is realized, but over longer periods of time formation of basic cup...

  12. Ductile superconducting copper-base alloys.

    PubMed

    Tsuei, C C

    1973-04-06

    A new class of ductile superconductors has been prepared by casting and appropriate heat treatments. These alloys superconduct between 4 degrees and 18 degrees K and contain at least 90 atom percent copper and a superconducting phase such as Nb(3)Sn or niobium. They can be processed into wires by conventional metallurgical techniques.

  13. Copper toxicity in aquaculture: A practical approach

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Copper sulfate has been used in aquaculture for many years to control weeds, algae, snails (which carry catfish trematode), and ecto-parasitic organisms in catfish production. Our research has also shown it to be safe and effective to treat fungus on various fish eggs (catfish, hybrid striped bass,...

  14. Status of copper sulfate research at SNARC

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An overview of the Technical Sections completed and being worked on for the New Animal Drug Application (NADA) for copper sulfate will be given. The change in Sponsorship will also be discussed. The Initial label claim will be “For the treatment of ichthyophthiriasis (Ichthyophthirius multifiliis)...

  15. Zirconium modified nickel-copper alloy

    NASA Technical Reports Server (NTRS)

    Whittenberger, J. D. (Inventor)

    1977-01-01

    An improved material for use in a catalytic reactor which reduces nitrogen oxide from internal combustion engines is in the form of a zirconium-modified, precipitation-strengthened nickel-copper alloy. This material has a nominal composition of Ni-30 Cu-0.2 Zr and is characterized by improved high temperature mechanical properties.

  16. Placenta Copper Transport Proteins in Preeclampsia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Placental insufficiency underlying preeclampsia (PE) is associated with impaired placental angiogenesis. As copper (Cu) is essential to angiogenesis, we investigated differences in the expression of placental Cu transporters Menkes (ATP7A), Wilsons (ATP7B) and the Cu chaperone (CCS) for superoxide d...

  17. Antistatic Polycarbonate/Copper Oxide Composite

    NASA Technical Reports Server (NTRS)

    Kovich, Michael; Rowland, George R., Jr.

    2003-01-01

    A composite material consisting of polycarbonate filled with copper oxide has been found to be suitable as an antistatic material. This material was developed to satisfy a requirement for an antistatic material that has a mass density less than that of aluminum and that exhibits an acceptably low level of outgassing in a vacuum.

  18. Fluidized bed electrowinning of copper. Final report

    SciTech Connect

    1997-07-01

    The objectives of the study were to: design and construct a 10,000- amp fluidized bed electrowinning cell for the recovery of copper from acidic sulfate solutions; demonstrate the technical feasibility of continuous particle recirculation from the electrowinning cell with the ultimate goal of continuous particle removal; and measure cell efficiency as a function of operating conditions.

  19. Australia's big copper-uranium deposit

    SciTech Connect

    Lyons, L.A.

    1981-07-01

    A combination of studies of satellite imagery with emphasis on lineament analysis, conventional gravity studies, aerial and ground magnetic surveys, theoretical and empirical modeling contributed to the discovery of the Roxby Downs/Olympic Dam deposit. The main ore body could contain as much as 750,000,000 tons of ore at grades of 1.5 percent copper.

  20. Preparation of graphite dispersed copper composite with intruding graphite particles in copper plate

    NASA Astrophysics Data System (ADS)

    Noor, Abdul Muizz Mohd; Ishikawa, Yoshikazu; Yokoyama, Seiji

    2017-01-01

    In this study, it was attempted that copper-graphite composite was prepared locally on the surface of a copper plate with using a spot welding machine. Experiments were carried out with changing the compressive load, the repetition number of the compression and the electrical current in order to study the effect of them on carbon content and Vickers hardness on the copper plate surface. When the graphite was pushed into copper plate only with the compressive load, the composite was mainly hardened by the work hardening. The Vickers hardness increased linearly with an increase in the carbon content. When an electrical current was energized through the composite at the compression, the copper around the graphite particles were heated to the temperature above approximately 2100 K and melted. The graphite particles partially or entirely dissolved into the melt. The graphite particles were precipitated from the melt under solidification. In addition, this high temperature caused the improvement of wetting of copper to graphite. This high temperature caused the annealing, and reduced the Vickers hardness. Even in this case, the Vickers hardness increased with an increase in the carbon content. This resulted from the dispersion hardening.

  1. Copper recovery and cyanide oxidation by electrowinning from a spent copper-cyanide electroplating electrolyte.

    PubMed

    Dutra, A J B; Rocha, G P; Pombo, F R

    2008-04-01

    Copper-cyanide bleed streams arise from contaminated baths from industrial electroplating processes due to the buildup of impurities during continuous operation. These streams present an elevated concentration of carbonate, cyanide and copper, constituting a heavy hazard, which has to be treated for cyanide destruction and heavy metals removal, according to the local environmental laws. In the Brazilian Mint, bleed streams are treated with sodium hypochlorite, to destroy cyanide and precipitate copper hydroxide, a solid hazardous waste that has to be disposed properly in a landfill or treated for metal recovery. In this paper, a laboratory-scale electrolytic cell was developed to remove the copper from the bleed stream of the electroplating unit of the Brazilian Mint, permitting its reutilization in the plant and decreasing the amount of sludge to waste. Under favorable conditions copper recoveries around 99.9% were achieved, with an energy consumption of about 11 kWh/kg, after a 5-h electrolysis of a bath containing copper and total cyanide concentrations of 26 and 27 g/L, respectively. Additionally, a substantial reduction of the cyanide concentration was also achieved, decreasing the pollution load and final treatment costs.

  2. Fabrication of Elemental Copper by Intense Pulsed Light Processing of a Copper Nitrate Hydroxide Ink.

    PubMed

    Draper, Gabriel L; Dharmadasa, Ruvini; Staats, Meghan E; Lavery, Brandon W; Druffel, Thad

    2015-08-05

    Printed electronics and renewable energy technologies have shown a growing demand for scalable copper and copper precursor inks. An alternative copper precursor ink of copper nitrate hydroxide, Cu2(OH)3NO3, was aqueously synthesized under ambient conditions with copper nitrate and potassium hydroxide reagents. Films were deposited by screen-printing and subsequently processed with intense pulsed light. The Cu2(OH)3NO3 quickly transformed in less than 100 s using 40 (2 ms, 12.8 J cm(-2)) pulses into CuO. At higher energy densities, the sintering improved the bulk film quality. The direct formation of Cu from the Cu2(OH)3NO3 requires a reducing agent; therefore, fructose and glucose were added to the inks. Rather than oxidizing, the thermal decomposition of the sugars led to a reducing environment and direct conversion of the films into elemental copper. The chemical and physical transformations were studied with XRD, SEM, FTIR and UV-vis.

  3. Simultaneous Platinum and Copper Ion Attachment to a Human Copper Chaperone Protein

    NASA Astrophysics Data System (ADS)

    Hodak, Miroslav; Cvitkovic, John; Yu, Corey; Dmitriev, Oleg; Kaminski, George; Bernholc, Jerry

    2015-03-01

    Cisplatin is a potent anti-cancer drug based on a platinum ion. However, its effectiveness is decreased by cellular resistance, which involves cisplatin attaching to copper transport proteins. One of such proteins is Atox1, where cisplatin attaches to the copper binding site. Surprisingly, it was shown that both cisplatin and copper can attach to Atox1 at the same time. To study this double metal ion attachment, we use the KS/FD DFT method, which combines Kohn-Sham DFT with frozen-density DFT to achieve efficient quantum-mechanical description of explicit solvent. Calculations have so far investigated copper ion attachment to CXXC motifs present in Atox1. The addition of the platinum ion and the competition between the two metals is currently being studied. These calculations start from a molecular mechanics (MM) structural model, in which glutathione groups provide additional ligands to the Pt ion. Our goals are to identify possible Cu-Pt structures and to determine whether copper/platinum attachment is competitive, independent, or cooperative. Results will be compared to the 1H, N1 5 -HSQC NMR experiments, in which binding of copper and cisplatin to Atox1 produces distinct secondary chemical shift signatures, allowing for kinetic studies of simultaneous metal binding.

  4. Experimental and theoretical investigation of fatigue life in reusable rocket thrust chambers

    NASA Technical Reports Server (NTRS)

    Hannum, N. P.; Kasper, H. J.; Pavli, A. J.

    1976-01-01

    During a test program to investigate low-cycle thermal fatigue, 13 rocket combustion chambers were fabricated and cyclically test fired to failure. Six oxygen-free, high-conductivity (OFHC) copper and seven Amzirc chambers were tested. The failures in the OFHC copper chambers were not typical fatigue failures but are described as creep rupture enhanced by ratcheting. The coolant channels bulged toward the chamber centerline, resulting in progressive thinning of the wall during each cycle. The failures in the Amzirc alloy chambers were caused by low-cycle thermal fatigue. The zirconium in this alloy was not evenly distributed in the chamber materials. The life that was achieved was nominally the same as would have been predicted from OFHC copper isothermal test data.

  5. Survival and Growth in the Presence of Elevated Copper: Transcriptional Profiling of Copper-Stressed Pseudomonas aeruginosa†

    PubMed Central

    Teitzel, Gail M.; Geddie, Ashley; De Long, Susan K.; Kirisits, Mary Jo; Whiteley, Marvin; Parsek, Matthew R.

    2006-01-01

    Transcriptional profiles of Pseudomonas aeruginosa exposed to two separate copper stress conditions were determined. Actively growing bacteria subjected to a pulse of elevated copper for a short period of time was defined as a “copper-shocked” culture. Conversely, copper-adapted populations were defined as cells actively growing in the presence of elevated copper. Expression of 405 genes changed in the copper-shocked culture, compared to 331 genes for the copper-adapted cultures. Not surprisingly, there were genes identified in common to both conditions. For example, both stress conditions resulted in up-regulation of genes encoding several active transport functions. However, there were some interesting differences between the two types of stress. Only copper-adapted cells significantly altered expression of passive transport functions, down-regulating expression of several porins belonging to the OprD family. Copper shock produced expression profiles suggestive of an oxidative stress response, probably due to the participation of copper in Fenton-like chemistry. Copper-adapted populations did not show such a response. Transcriptional profiles also indicated that iron acquisition is fine-tuned in the presence of copper. Several genes induced under iron-limiting conditions, such as the siderophore pyoverdine, were up-regulated in copper-adapted populations. Interesting exceptions were the genes involved in the production of the siderophore pyochelin, which were down-regulated. Analysis of the copper sensitivity of select mutant strains confirmed the array data. These studies suggest that two resistance nodulation division efflux systems, a P-type ATPase, and a two-component regulator were particularly important for copper tolerance in P. aeruginosa. PMID:17015663

  6. Rapid Copper Acquisition by Developing Murine Mesothelioma: Decreasing Bioavailable Copper Slows Tumor Growth, Normalizes Vessels and Promotes T Cell Infiltration

    PubMed Central

    Crowe, Andrew; Jackaman, Connie; Beddoes, Katie M.; Ricciardo, Belinda; Nelson, Delia J.

    2013-01-01

    Copper, an essential trace element acquired through nutrition, is an important co-factor for pro-angiogenic factors including vascular endothelial growth factor (VEGF). Decreasing bioavailable copper has been used as an anti-angiogenic and anti-cancer strategy with promising results. However, the role of copper and its potential as a therapy in mesothelioma is not yet well understood. Therefore, we monitored copper levels in progressing murine mesothelioma tumors and analyzed the effects of lowering bioavailable copper. Copper levels in tumors and organs were assayed using atomic absorption spectrophotometry. Mesothelioma tumors rapidly sequestered copper at early stages of development, the copper was then dispersed throughout growing tumor tissues. These data imply that copper uptake may play an important role in early tumor development. Lowering bioavailable copper using the copper chelators, penicillamine, trientine or tetrathiomolybdate, slowed in vivo mesothelioma growth but did not provide any cures similar to using cisplatin chemotherapy or anti-VEGF receptor antibody therapy. The impact of copper lowering on tumor blood vessels and tumor infiltrating T cells was measured using flow cytometry and confocal microscopy. Copper lowering was associated with reduced tumor vessel diameter, reduced endothelial cell proliferation (reduced Ki67 expression) and lower surface ICAM/CD54 expression implying reduced endothelial cell activation, in a process similar to endothelial normalization. Copper lowering was also associated with a CD4+ T cell infiltrate. In conclusion, these data suggest copper lowering is a potentially useful anti-mesothelioma treatment strategy that slows tumor growth to provide a window of opportunity for inclusion of other treatment modalities to improve patient outcomes. PMID:24013775

  7. Response of plasma copper, ceruloplasmin, iron and ions in carp, Cyprinus carpio to waterborne copper ion and nanoparticle exposure.

    PubMed

    Hedayati, Aliakbar; Hoseini, Seyyed Morteza; Hoseinifar, Seyed Hossein

    2016-01-01

    In this study, Cyprinus carpio was exposed to 0.25mgL(-1) copper as either copper sulfate (CuSO4) or copper oxide nanoparticles (nano-Cu), and 25mgL(-1) copper as nano-Cu for 14days. CuSO4 and high concentration of nano-Cu led to a significant increase in plasma total copper levels. Plasma free copper levels increased significantly in all copper-exposed treatments. Except for low concentration of nano-Cu after 7 and 14days, copper exposure generally led to a significant decrease in plasma ceruloplasmin levels. Plasma iron levels increased significantly in CuSO4 (all times) and nano-Cu (7th and 14th days) treatments. A significant elevation in plasma total iron binding capacity (TIBC) was observed after 3days in the fish exposed to low concentration nano-Cu, and after 14days in all copper-exposed treatments. Transferrin saturation (TSA) ratio showed significant increase in CuSO4 (3rd and 7th days) and the high concentration nano-Cu (7th day) treatments. Decrease in plasma chloride (7th and 14th days) and sodium (14th days) was observed in CuSO4 treatment. In conclusion, the results suggest that ionic copper is mainly absorbed via fish gill, whereas, nano-copper are more likely absorbed via gut. Also, data suggest that ionic copper has more adverse effects on the examined plasma biochemical characteristics compared to the equivalent nano-copper concentration, which may be due to the lower copper absorption by fish in the nano-copper suspension.

  8. Copper Deposits in Sedimentary and Volcanogenic Rocks

    USGS Publications Warehouse

    Tourtelot, Elizabeth B.; Vine, James David

    1976-01-01

    Copper deposits occur in sedimentary and volcanogenic rocks within a wide variety of geologic environments where there may be little or no evidence of hydrothermal alteration. Some deposits may be hypogene and have a deep-seated source for the ore fluids, but because of rapid cooling and dilution during syngenetic deposition on the ocean floor, the resulting deposits are not associated with hydrothermal alteration. Many of these deposits are formed at or near major tectonic features on the Earth's crust, including plate boundaries, rift valleys, and island arcs. The resulting ore bodies may be stratabound and either massive or disseminated. Other deposits form in rocks deposited in shallow-marine, deltaic, and nonmarine environments by the movement and reaction of interstratal brines whose metal content is derived from buried sedimentary and volcanic rocks. Some of the world's largest copper deposits were probably formed in this manner. This process we regard as diagenetic, but some would regard it as syngenetic, if the ore metals are derived from disseminated metal in the host-rock sequence, and others would regard the process as epigenetic, if there is demonstrable evidence of ore cutting across bedding. Because the oxidation associated with diagenetic red beds releases copper to ground-water solutions, red rocks and copper deposits are commonly associated. However, the ultimate size, shape, and mineral zoning of a deposit result from local conditions at the site of deposition - a logjam in fluvial channel sandstone may result in an irregular tabular body of limited size; a petroleum-water interface in an oil pool may result in a copper deposit limited by the size and shape of the petroleum reservoir; a persistent thin bed of black shale may result in a copper deposit the size and shape of that single bed. The process of supergene enrichment has been largely overlooked in descriptions of copper deposits in sedimentary rocks. However, supergene processes may be

  9. Metal-metal bonding using silver/copper nanoparticles

    NASA Astrophysics Data System (ADS)

    Kobayashi, Y.; Maeda, T.; Yasuda, Y.; Morita, T.

    2016-08-01

    A method for producing nanoparticles composed of silver and copper and a metal-metal bonding technique using the silver/copper nanoparticles are proposed. The method consists of three steps. First, copper oxide nanoparticles are produced by mixing Cu(NO3)2 aqueous solution and NaOH aqueous solution. Second, copper metal nanoparticles are fabricated by reducing the copper oxide nanoparticles with hydrazine in the presence of poly(vinylpyrrolidone) (PVP). Third, silver/copper nanoparticles are synthesized by reducing Ag+ ions with hydrazine in the presence of the copper metal nanoparticles. Initial concentrations in the final silver/copper particle colloid, composed of 0.0075 M Cu2+, 0.0025 M Ag+, 1.0 g/L PVP, and 0.6 M hydrazine, produced silver/copper nanoparticles with an average size of 49 nm and a crystal size of 16.8 nm. Discs of copper metal were successfully bonded by the silver/copper nanoparticles under annealing at 400 °C and pressurizing at 1.2 MPa for 5 min in not only hydrogen gas but also nitrogen gas. The shear force required to separate the bonded discs was 22.3 MPa for the hydrogen gas annealing and 14.9 MPa for the nitrogen gas annealing (namely, 66.8 % of that for hydrogen gas annealing).

  10. Modeling MIC copper release from drinking water pipes.

    PubMed

    Pizarro, Gonzalo E; Vargas, Ignacio T; Pastén, Pablo A; Calle, Gustavo R

    2014-06-01

    Copper is used for household drinking water distribution systems given its physical and chemical properties that make it resistant to corrosion. However, there is evidence that, under certain conditions, it can corrode and release unsafe concentrations of copper to the water. Research on drinking water copper pipes has developed conceptual models that include several physical-chemical mechanisms. Nevertheless, there is still a necessity for the development of mathematical models of this phenomenon, which consider the interaction among physical-chemical processes at different spatial scales. We developed a conceptual and a mathematical model that reproduces the main processes in copper release from copper pipes subject to stagnation and flow cycles, and corrosion is associated with biofilm growth on the surface of the pipes. We discuss the influence of the reactive surface and the copper release curves observed. The modeling and experimental observations indicated that after 10h stagnation, the main concentration of copper is located close to the surface of the pipe. This copper is associated with the reactive surface, which acts as a reservoir of labile copper. Thus, for pipes with the presence of biofilm the complexation of copper with the biomass and the hydrodynamics are the main mechanisms for copper release.

  11. Growth of single-crystalline particles of metallic copper

    NASA Astrophysics Data System (ADS)

    Guo, Jinlei; Shen, Shaobo; Zhao, Yingshi; Wang, Fuming

    2016-10-01

    Most of ultrafine particles of metallic copper reported so far were of polycrystalline structures. Here, some ultrafine particles of metallic copper of single-crystalline structure were synthesized in gas phase. Some mixtures of a raw copper powder (about 79 μm) and sodium chloride powder were used as the precursor materials. The materials were chlorinated by dry chlorine at 400 °C. Some anhydrous eutectics composed of copper chlorides and sodium chloride were thus obtained. The eutectics were first heated in situ up to 900 °C and then carried to a gas space by evaporation using a flowing Argon, where they met H2 and were reduced to metallic copper particles. It was found that all these copper particles prepared were of single-crystalline structure irrespective of the molar ratio of raw copper and sodium chloride. When the molar ratio of NaCl to Cu in the precursor materials was 1 to 3, some dispersed octahedral particles of single-crystalline copper with an average size of 776 nm were prepared. However, when the ratio was increased to 4 to 1, some dispersed spherical particles of single-crystalline copper with a size of 92 nm were obtained. No impurities from the two shapes of copper particles were detected. The mechanisms involved in controlling the shape and size of copper particles were proposed.

  12. Oxidation-assisted graphene heteroepitaxy on copper foil.

    PubMed

    Reckinger, Nicolas; Tang, Xiaohui; Joucken, Frédéric; Lajaunie, Luc; Arenal, Raul; Dubois, Emmanuel; Hackens, Benoît; Henrard, Luc; Colomer, Jean-François

    2016-11-10

    We propose an innovative, easy-to-implement approach to synthesize aligned large-area single-crystalline graphene flakes by chemical vapor deposition on copper foil. This method doubly takes advantage of residual oxygen present in the gas phase. First, by slightly oxidizing the copper surface, we induce grain boundary pinning in copper and, in consequence, the freezing of the thermal recrystallization process. Subsequent reduction of copper under hydrogen suddenly unlocks the delayed reconstruction, favoring the growth of centimeter-sized copper (111) grains through the mechanism of abnormal grain growth. Second, the oxidation of the copper surface also drastically reduces the nucleation density of graphene. This oxidation/reduction sequence leads to the synthesis of aligned millimeter-sized monolayer graphene domains in epitaxial registry with copper (111). The as-grown graphene flakes are demonstrated to be both single-crystalline and of high quality.

  13. Canadian soil quality guidelines for copper: Environmental and human health

    SciTech Connect

    1997-12-31

    This report begins with background information on the physical and chemical properties of copper, the production and use of copper in Canada, its levels in the Canadian environment, and existing guidelines and criteria regarding copper concentrations in various media. It then reviews the environmental fate and behaviour of copper, notably in the soil; the behavior and effects of copper in biota, including soil microbial processes, terrestrial plants and invertebrates, livestock and wildlife, and bioaccumulation; and the pharmacokinetics and toxicology of copper in mammals and humans, concluding with an overall toxicological evaluation and human exposure estimates. This information is used to derive environmental and human health soil quality guidelines for copper to protect environmental and human health receptors, for agricultural, residential/parkland, commercial, and industrial land uses.

  14. Mitochondrial dysfunction in neurodegenerative diseases associated with copper imbalance.

    PubMed

    Rossi, Luisa; Lombardo, Marco F; Ciriolo, Maria R; Rotilio, Giuseppe

    2004-03-01

    Copper is an essential transition metal ion for the function of key metabolic enzymes, but its uncontrolled redox reactivity is source of reactive oxygen species. Therefore a network of transporters strictly controls the trafficking of copper in living systems. Deficit, excess, or aberrant coordination of copper are conditions that may be detrimental, especially for neuronal cells, which are particularly sensitive to oxidative stress. Indeed, the genetic disturbances of copper homeostasis, Menkes' and Wilson's diseases, are associated with neurodegeneration. Furthermore, copper interacts with the proteins that are the hallmarks of neurodegenerative disorders, such as Alzheimer's disease, Parkinson's disease, prion diseases, and familial amyotrophic lateral sclerosis. In all cases, copper-mediated oxidative stress is linked to mitochondrial dysfunction, which is a common feature of neurodegeneration. In particular we recently demonstrated that in copper deficiency, mitochondrial function is impaired due to decreased activity of cytochrome c oxidase, leading to production of reactive oxygen species, which in turn triggers mitochondria-mediated apoptotic neurodegeneration.

  15. Laboratory-Based Model of Microbiologically Induced Corrosion of Copper

    PubMed Central

    Bremer, Philip J.; Geesey, Gill G.

    1991-01-01

    The interactions of bacteria isolated from corroded copper coupons on thin films of copper evaporated onto germanium internal reflection elements were evaluated nondestructively in real time by attentuated total reflectance Fourier transform infrared spectroscopy. The films were stable in the presence of flowing or static sterile culture medium. When exposed to and colonized by the bacterium CCI 8, the copper thin film corroded. Corrosion was enhanced under quiescent conditions. In conjunction with corrosion of the copper thin film was an increase in the concentration of polysaccharide material at the copper-biofilm interface. A different bacterium (CCI 11) did not corrode the copper thin film, and the establishment of this bacterium on the copper surface prevented corrosion of the thin film by CCI 8. Images PMID:16348520

  16. Physical, chemical and antimicrobial characterization of copper-bearing material

    NASA Astrophysics Data System (ADS)

    Li, Bowen; Hwang, Jiann-Yang; Drelich, Jaroslaw; Popko, Domenic; Bagley, Susan

    2010-12-01

    Arsenic, cadmium, copper, mercury, silver, and zinc are elements with strong antimicrobial properties. Among them, copper is more environmentally friendly and has both good antibacterial and antifungal properties. It has been shown that copper can even be effective against new viruses such as avian influenza (H5N1). Development of copper-bearing materials for various applications, therefore, is receiving increased attention. The Keweenaw Peninsula of Michigan was the largest native copper mining regions of North America at the turn of the 20th century. Copper was extracted by mining the copper-rich basaltic rock, and steamdriven stamp mills were used to process a great volume of low-grade ores, resulting in huge amounts of crushed waste ore called stamp sands. Approximately 500 million tons of stamp sand were discarded. This material is investigated in this study as an example for the development of antimicrobial materials.

  17. Copper deficiency in Tule Elk at Point Reyes, California

    USGS Publications Warehouse

    Gogan, Peter J.P.; Jessup, David A.; Akeson, Mark

    1989-01-01

    Tule elk (Cervus elaphus nannodes) reintroduced to Point Reyes, Calif., in 1978 exhibited gross signs of copper deficiency by June 1979. Copper levels in liver (x=5.9 ppm) and serum (0.42 ppm) of elk in Point Reyes were below levels in adult tule elk from other locations in California (liver, x=80 ppm; serum, x=1.4 ppm). These levels were consistent with documented copper deficiencies in wild and domestic ruminants. Copper serum levels increased in response to copper enriched dietary supplements and declined after the elk stopped eating the supplements. Analysis of plant and soil samples showed both are deficient in copper and normal in molybdenum and sulfur-sulfates. Deficiency in plants and soils at Point Reyes are probably due to low copper levels in the underlying granitic parent material.

  18. Diabetic cardiomyopathy is associated with defective myocellular copper regulation and both defects are rectified by divalent copper chelation

    PubMed Central

    2014-01-01

    Background Heart disease is the leading cause of death in diabetic patients, and defective copper metabolism may play important roles in the pathogenesis of diabetic cardiomyopathy (DCM). The present study sought to determine how myocardial copper status and key copper-proteins might become impaired by diabetes, and how they respond to treatment with the Cu (II)-selective chelator triethylenetetramine (TETA) in DCM. Methods Experiments were performed in Wistar rats with streptozotocin (STZ)-induced diabetes with or without TETA treatment. Cardiac function was analyzed in isolated-perfused working hearts, and myocardial total copper content measured by particle-induced x-ray emission spectroscopy (PIXE) coupled with Rutherford backscattering spectrometry (RBS). Quantitative expression (mRNA and protein) and/or activity of key proteins that mediate LV-tissue-copper binding and transport, were analyzed by combined RT-qPCR, western blotting, immunofluorescence microscopy, and enzyme activity assays. Statistical analysis was performed using Student’s t-tests or ANOVA and p-values of < 0.05 have been considered significant. Results Left-ventricular (LV) copper levels and function were severely depressed in rats following 16-weeks’ diabetes, but both were unexpectedly normalized 8-weeks after treatment with TETA was instituted. Localized myocardial copper deficiency was accompanied by decreased expression and increased polymerization of the copper-responsive transition-metal-binding metallothionein proteins (MT1/MT2), consistent with impaired anti-oxidant defences and elevated susceptibility to pro-oxidant stress. Levels of the high-affinity copper transporter-1 (CTR1) were depressed in diabetes, consistent with impaired membrane copper uptake, and were not modified by TETA which, contrastingly, renormalized myocardial copper and increased levels and cell-membrane localization of the low-affinity copper transporter-2 (CTR2). Diabetes also lowered indexes of

  19. Colloidal and electrochemical aspects of copper-CMP

    NASA Astrophysics Data System (ADS)

    Sun, Yuxia

    Copper based interconnects with low dielectric constant layers are currently used to increase interconnect densities and reduce interconnect time delays in integrated circuits. The technology used to develop copper interconnects involves Chemical Mechanical Planarization (CMP) of copper films deposited on low-k layers (silica or silica based films), which is carried out using slurries containing abrasive particles. One issue using such a structure is copper contamination over dielectric layers (SiO2 film), if not reduced, this contamination will cause current leakage. In this study, the conditions conducive to copper contamination onto SiO2 films during Cu-CMP process were studied, and a post-CMP cleaning technique was discussed based on experimental results. It was found that the adsorption of copper onto a silica surface is kinetically fast (<0.5 minute). The amount of copper absorbed is pH and concentration dependent and affected by presence of H2O2, complexing agents, and copper corrosion inhibitor Benzotrazole. Based on de-sorption results, DI water alone was unable to reduce adsorbed copper to an acceptable level, especially for adsorption that takes place at a higher pH condition. The addition of complex agent, citric acid, proved effective in suppressing copper adsorption onto oxide silica during polishing or post-CMP cleaning by forming stable copper-CA complexes. Surface Complexation Modeling was used to simulate copper adsorption isotherms and predict the copper contamination levels on SiO2 surfaces. Another issue with the application of copper CMP is its environmental impact. CMP is a costly process due to its huge consumption of pure water and slurry. Additionally, Cu-CMP processing generates a waste stream containing certain amounts of copper and abrasive slurry particles. In this study, the separation technique electrocoagulation was investigated to remove both copper and abrasive slurry particles simultaneously. For effluent containing ˜40 ppm

  20. Antimicrobial Properties of Copper Nanoparticles and Amino Acid Chelated Copper Nanoparticles Produced by Using a Soya Extract.

    PubMed

    DeAlba-Montero, I; Guajardo-Pacheco, Jesús; Morales-Sánchez, Elpidio; Araujo-Martínez, Rene; Loredo-Becerra, G M; Martínez-Castañón, Gabriel-Alejandro; Ruiz, Facundo; Compeán Jasso, M E

    2017-01-01

    This paper reports a comparison of the antibacterial properties of copper-amino acids chelates and copper nanoparticles against Escherichia coli, Staphylococcus aureus, and Enterococcus faecalis. These copper-amino acids chelates were synthesized by using a soybean aqueous extract and copper nanoparticles were produced using as a starting material the copper-amino acids chelates species. The antibacterial activity of the samples was evaluated by using the standard microdilution method (CLSI M100-S25 January 2015). In the antibacterial activity assays copper ions and copper-EDTA chelates were included as references, so that copper-amino acids chelates can be particularly suitable for acting as an antibacterial agent, so they are excellent candidates for specific applications. Additionally, to confirm the antimicrobial mechanism on bacterial cells, MTT assay (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) was carried out. A significant enhanced antimicrobial activity and a specific strain were found for copper chelates over E. faecalis. Its results would eventually lead to better utilization of copper-amino acids chelate for specific application where copper nanoparticles can be not used.

  1. Antimicrobial Properties of Copper Nanoparticles and Amino Acid Chelated Copper Nanoparticles Produced by Using a Soya Extract

    PubMed Central

    DeAlba-Montero, I.; Morales-Sánchez, Elpidio; Araujo-Martínez, Rene

    2017-01-01

    This paper reports a comparison of the antibacterial properties of copper-amino acids chelates and copper nanoparticles against Escherichia coli, Staphylococcus aureus, and Enterococcus faecalis. These copper-amino acids chelates were synthesized by using a soybean aqueous extract and copper nanoparticles were produced using as a starting material the copper-amino acids chelates species. The antibacterial activity of the samples was evaluated by using the standard microdilution method (CLSI M100-S25 January 2015). In the antibacterial activity assays copper ions and copper-EDTA chelates were included as references, so that copper-amino acids chelates can be particularly suitable for acting as an antibacterial agent, so they are excellent candidates for specific applications. Additionally, to confirm the antimicrobial mechanism on bacterial cells, MTT assay (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) was carried out. A significant enhanced antimicrobial activity and a specific strain were found for copper chelates over E. faecalis. Its results would eventually lead to better utilization of copper-amino acids chelate for specific application where copper nanoparticles can be not used. PMID:28286459

  2. [Newly leaching method of copper from waste print circuit board using hydrochloric acid/n-butylamine/copper sulfate].

    PubMed

    Wang, Hong-Yan; Cui, Zhao-Jie; Yao, Ya-Wei

    2010-12-01

    A newly leaching method of copper from waste print circuit board was established by using hydrochloric acid-n-butylamine-copper sulfate mixed solution. The conditions of leaching were optimized by changing the hydrochloric acid, n-butylamine, copper sulfate,temperature and other conditions using copper as target mimics. The results indicated that copper could be leached completely after 8 h at 50 degrees C, hydrochloric acid concentration of 1.75 mol/L, n-butylamine concentration of 0.25 mol/L, and copper sulfate mass of 0.96 g. Under the conditions, copper leaching rates in waste print circuit board samples was up to 95.31% after 9 h. It has many advantages such as better effects, low cost, mild reaction conditions, leaching solution recycling.

  3. Construction of a high efficiency copper adsorption bacterial system via peptide display and its application on copper dye polluted wastewater.

    PubMed

    Maruthamuthu, Murali Kannan; Nadarajan, Saravanan Prabhu; Ganesh, Irisappan; Ravikumar, Sambandam; Yun, Hyungdon; Yoo, Ik-Keun; Hong, Soon Ho

    2015-11-01

    For the construction of an efficient copper waste treatment system, a cell surface display strategy was employed. The copper adsorption ability of recombinant bacterial strains displaying three different copper binding peptides were evaluated in LB Luria-Bertani medium (LB), artificial wastewater, and copper phthalocyanine containing textile dye industry wastewater samples. Structural characteristics of the three peptides were also analyzed by similarity-based structure modeling. The best binding peptide was chosen for the construction of a dimeric peptide display and the adsorption ability of the monomeric and dimeric peptide displayed strains were compared. The dimeric peptide displayed strain showed superior copper adsorption in all three tested conditions (LB, artificial wastewater, and textile dye industry wastewater). When the strains were exposed to copper phthalocyanine dye polluted wastewater, the dimeric peptide display [543.27 µmol/g DCW dry cell weight (DCW)] showed higher adsorption of copper when compared with the monomeric strains (243.53 µmol/g DCW).

  4. Matrix Sputtering into Liquid Mercaptan: From Blue-Emitting Copper Nanoclusters to Red-Emitting Copper Sulfide Nanoclusters.

    PubMed

    Porta, Matteo; Nguyen, Mai Thanh; Tokunaga, Tomoharu; Ishida, Yohei; Liu, Wei-Ren; Yonezawa, Tetsu

    2016-11-22

    A modified magnetron sputtering technique using pentaerythritol tetrakis(3-mercaptopropionate) (PEMP) as a stabilizing agent and liquid dispersion medium was developed to generate photoluminescent copper nanoclusters. The results reveal that, over time, the as-prepared blue-emitting copper nanoclusters were converted to red-emitting copper sulfide nanoclusters. The formation of copper oxide as an intermediate during the conversion of copper to copper sulfide nanoclusters was demonstrated. Furthermore, based on the mechanism of formation of copper sulfide, the kinetics of the conversion process could be controlled via ultraviolet (UV) irradiation of the as-synthesized dispersion. These findings shed light on the formation and conversion of nanoclusters obtained via sputtering into liquid, demonstrating that the method is highly versatile for producing metal nanoclusters and compounds with tailorable composition and optical properties.

  5. Urinary excretion of copper, zinc and iron with and without D-penicillamine administration in relation to hepatic copper concentration in dogs.

    PubMed

    Fieten, H; Hugen, S; van den Ingh, T S G A M; Hendriks, W H; Vernooij, J C M; Bode, P; Watson, A L; Leegwater, P A J; Rothuizen, J

    2013-08-01

    Hereditary copper-associated hepatitis in dogs resembles Wilson's disease, a copper storage disease in humans. Values for urinary copper excretion are well established in the diagnostic protocol of Wilson's disease, whereas in dogs these have not been evaluated. The objectives of this study were to characterize both basal and D-penicillamine induced urinary copper, zinc and iron excretion in dogs in relation to hepatic copper concentration. Beagles, Beagle-Bedlington terrier cross-breeds homozygous for the COMMD1 gene mutation that causes copper toxicosis, and Labrador retrievers with normal or increased hepatic copper concentrations were investigated. The hepatic copper phenotype was determined by histological evaluation of liver biopsies and measurement of the hepatic copper concentration by instrumental neutron activation analysis. Urinary excretion of copper, iron and zinc was measured via inductively coupled plasma optical emission spectrometry under basal conditions and after oral administration of a single dose (20mg/kg bodyweight) of the chelator D-penicillamine. There was a rapid increase in urinary excretion of copper and zinc, but not iron after D-penicillamine administration. This increase was not different between dogs with high or normal hepatic copper concentrations. D-penicillamine-induced urinary copper excretion and the copper/creatinine ratio did not correlate with hepatic copper concentrations in the dogs studied, although basal urinary copper/zinc ratios did correlate with hepatic copper concentrations in Labrador retrievers. The latter parameter may be useful in diagnostic and follow-up protocols for copper-associated hepatitis in Labrador retrievers.

  6. A Multinuclear Copper(I) Cluster Forms the Dimerization Interface in Copper-Loaded Human Copper Chaperone for Superoxide Dismutase

    SciTech Connect

    Stasser, J.P.; Siluvai, G.S.; Barry, A.N.; Blackburn, N.J.

    2009-06-04

    Copper binding and X-ray aborption spectroscopy studies are reported on untagged human CCS (hCCS; CCS = copper chaperone for superoxide dismutase) isolated using an intein self-cleaving vector and on single and double Cys to Ala mutants of the hCCS MTCQSC and CSC motifs of domains 1 (D1) and 3 (D3), respectively. The results on the wild-type protein confirmed earlier findings on the CCS-MBP (maltose binding protein) constructs, namely, that Cu(I) coordinates to the CXC motif, forming a cluster at the interface of two D3 polypeptides. In contrast to the single Cys to Ser mutations of the CCS-MBP protein (Stasser, J. P., Eisses, J. F., Barry, A. N., Kaplan, J. H., and Blackburn, N. J. (2005) Biochemistry 44, 3143-3152), single Cys to Ala mutations in D3 were sufficient to eliminate cluster formation and significantly reduce CCS activity. Analysis of the intensity of the Cu-Cu cluster interaction in C244A, C246A, and C244/246A variants suggested that the nuclearity of the cluster was greater than 2 and was most consistent with a Cu4S6 adamantane-type species. The relationship among cluster formation, oligomerization, and metal loading was evaluated. The results support a model in which Cu(I) binding converts the apo dimer with a D2-D2 interface to a new dimer connected by cluster formation at two D3 CSC motifs. The predominance of dimer over tetramer in the cluster-containing species strongly suggests that the D2 dimer interface remains open and available for sequestering an SOD1 monomer. This work implicates the copper cluster in the reactive form and adds detail to the cluster nuclearity and how copper loading affects the oligomerization states and reactivity of CCS for its partner SOD1.

  7. The mechanism of copper uptake by tyrosinase from Bacillus megaterium.

    PubMed

    Kanteev, Margarita; Goldfeder, Mor; Chojnacki, Michał; Adir, Noam; Fishman, Ayelet

    2013-12-01

    Tyrosinase belongs to the type 3 copper enzyme family, containing a dinuclear copper center, CuA and CuB. It is mainly responsible for melanin production in a wide range of organisms. Although copper ions are essential for the activity of tyrosinase, the mechanism of copper uptake is still unclear. We have recently determined the crystal structure of tyrosinase from Bacillus megaterium (TyrBm) and revealed that this enzyme has tighter binding of CuA in comparison with CuB. Investigating copper accumulation in TyrBm, we found that the presence of copper has a more significant effect on the diphenolase activity. By decreasing the concentration of copper, we increased the diphenolase to monophenolase activity ratio twofold. Using a rational design approach, we identified five variants having an impact on copper uptake. We have found that a major role of the highly conserved Asn205 residue is to stabilize the orientation of the His204 imidazole ring in the binding site, thereby promoting the correct coordination of CuB. Further investigation of these variants revealed that Phe197, Met61, and Met184, which are located at the entrance to the binding site, not only play a role in copper uptake, but are also important for enhancing the diphenolase activity. We propose a mechanism of copper accumulation by the enzyme as well as an approach to changing the selectivity of TyrBm towards L-dopa production.

  8. The interaction of type of dietary carbohydrates with copper deficiency.

    PubMed

    Fields, M; Ferretti, R J; Smith, J C; Reiser, S

    1984-02-01

    The present study was designed to determine if the more severe copper deficiency in rats fed sucrose and fructose, as compared to starch, is due to a specific effect of the fructose or to a nonspecific effect of any simple carbohydrate. Seventy weanling male rats were fed, for 9 wk, copper-deficient diets or copper-supplemented diets containing either 62% starch, fructose, or glucose. Decreased hematocrit, serum copper, and ceruloplasmin concentrations but increased heart and liver weights, total liver lipid, and hepatic iron concentrations were found in all copper-deficient rats regardless of the dietary carbohydrate. Feeding rats the high glucose diet decreased plasma albumin and liver glycogen but increased blood urea nitrogen when compared to rats fed starch. However, rats fed fructose generally exhibited a more severe copper deficiency as compared to rats fed either starch or glucose. The severity was characterized by lower (p less than 0.05) body weight, liver glycogen, hematocrit, serum copper, and albumin. Conversely, liver and heart weights, blood urea nitrogen, and plasma glutamic oxaloacetic transaminase were higher (p less than 0.05). Plasma cholesterol was increased by copper deficiency only in rats fed fructose or glucose. During the study, 17 of the 40 rats fed copper-deficient diets died; 66% of those fed fructose, 26% fed glucose, and 30% fed starch. These results suggest that the fructose moiety of sucrose is responsible for the increased severity of copper deficiency in rats fed sucrose as compared to starch.

  9. Responses of environmental Amycolatopsis strains to copper stress.

    PubMed

    Dávila Costa, José Sebastián; Albarracín, Virginia Helena; Abate, Carlos Mauricio

    2011-10-01

    Copper is a redox-active metal, which acts as a catalyst in the formation of Reactive Oxygen Species (ROS) encouraging oxidative stress. Protection against oxidants is intrinsic to every living cell; however, in stress conditions, cells are forced to increase and expand their antioxidative network. In this work, the novel copper-resistant strain Amycolatopsis tucumanensis and the copper-sensitive Amycolatopsis eurytherma were grown under copper increasing concentrations in order to elucidate the dissimilar effects of the metal on the strains viability, mainly on morphology and antioxidant capacity. Although biosorbed copper encouraged ROS production in a dose-dependent manner in both strains, the increase in ROS production from the basal level to the stress conditions in A. tucumanensis is lesser than in the copper-sensitive strain; likewise, in presence of copper A. eurytherma suffered inexorable morphological alteration while A. tucumanensis was not affected. The levels of antioxidant enzymes and metallothioneins (MT) were all greater in A. tucumanensis than in A. eurytherma; in addition MT levels as well as superoxide dismutase and thioredoxin reductase activities in A. tucumanensis, were higher as higher the concentration of copper in the culture medium. This work has given evidence that an efficient antioxidant defense system might aid microorganisms to survive in copper-stress conditions; besides it constitutes the first report of oxidative stress study in the genus Amycolatopsis and contributes to enlarge the knowledge on the copper-resistance mechanisms of A. tucumanensis.

  10. Isolation and characterization of bacteria resistant to metallic copper surfaces.

    PubMed

    Santo, Christophe Espírito; Morais, Paula Vasconcelos; Grass, Gregor

    2010-03-01

    Metallic copper alloys have recently attracted attention as a new antimicrobial weapon for areas where surface hygiene is paramount. Currently it is not understood on a molecular level how metallic copper kills microbes, but previous studies have demonstrated that a wide variety of bacteria, including Escherichia coli, Staphylococcus aureus, and Clostridium difficile, are inactivated within minutes or a few hours of exposure. In this study, we show that bacteria isolated from copper alloy coins comprise strains that are especially resistant against the toxic properties exerted by dry metallic copper surfaces. The most resistant of 294 isolates were Gram-positive staphylococci and micrococci, Kocuria palustris, and Brachybacterium conglomeratum but also included the proteobacterial species Sphingomonas panni and Pseudomonas oleovorans. Cells of some of these bacterial strains survived on copper surfaces for 48 h or more. Remarkably, when these dry-surface-resistant strains were exposed to moist copper surfaces, resistance levels were close to those of control strains and MICs for copper ions were at or below control strain levels. This suggests that mechanisms conferring resistance against dry metallic copper surfaces in these newly isolated bacterial strains are different from well-characterized copper ion detoxification systems. Furthermore, staphylococci on coins did not exhibit increased levels of resistance to antibiotics, arguing against coselection with copper surface resistance traits.

  11. Copper bioaccumulation by the actinobacterium Amycolatopsis sp. AB0.

    PubMed

    Albarracín, Virginia Helena; Winik, Beatriz; Kothe, Erika; Amoroso, María Julia; Abate, Carlos Mauricio

    2008-10-01

    Amycolatopsis sp. AB0, a copper resistant actinobacterium isolated from polluted sediments, has shown high copper specific biopsortion ability (25 mg g(-1)). Two approaches were used to confirm metal accumulation in growing cells of Amycolatopsis sp. AB0; we performed subcellular fractioning assays which showed that the retained copper was associated with the extra-cellular fraction (exopolymer, 40%), but mainly within the cells. Intracellular distribution of copper was: 86% in the cytosolic fraction, 11% at the cell wall and 3% associated with the ribosome/membrane fraction. Its copper bioaccumulation ability was corroborated by using silver enhanced staining of copper with the Timm's reagent technique, which has not been used to detect metal deposits in bacteria before. In addition, we constructed specific oligonucleotides for targeting genes coding for copper P-Type ATPases that could be involved in the copper uptake ability of this strain. A 607 bp DNA fragment was amplified and sequenced from Amycolatopsis sp AB0. BLAST search analysis showed 71% protein homology of the deduced sequence with a putative cation-transporting ATPase of Nocardia farcinica and 65% with a copper translocating ATPase of Mycobacterium flavescens. To our knowledge this is the first report of the presence of copper P-type ATPase genes in the Amycolotopsis genus.

  12. Relation to copper of N-1, a nonobligate bacterial predator

    SciTech Connect

    Casida, L.E. Jr.

    1987-07-01

    Nonobligate bacterial predator strain N-1 was highly resistant to copper. In fact, it required more than minimal amounts of copper to initiate growth, but not for growth that followed growth initiation. Strain N-1 made a peptide growth initiation factor (GIF) to marshal copper from its environment for growth initiation. Production of this GIF occurred before the onset of growth initiation, but production was shut down if excess copper was present. At high copper levels, the time required for onset of growth initiation was directly related to the amount of copper that was present. At low copper levels, a similar graded response occurred for increments of added GIF. Agromyces ramosus is a predator in its own right, but it also is a prey species for strain N-1. A. ramosus was found to be very sensitivity to copper and to the copper GIF produced by N-1. It is possible that the copper GIF is the means used by N-1 to kill A. ramosus.

  13. The Yeast Copper Response Is Regulated by DNA Damage

    PubMed Central

    Dong, Kangzhen; Addinall, Stephen G.; Lydall, David

    2013-01-01

    Copper is an essential but potentially toxic redox-active metal, so the levels and distribution of this metal are carefully regulated to ensure that it binds to the correct proteins. Previous studies of copper-dependent transcription in the yeast Saccharomyces cerevisiae have focused on the response of genes to changes in the exogenous levels of copper. We now report that yeast copper genes are regulated in response to the DNA-damaging agents methyl methanesulfonate (MMS) and hydroxyurea by a mechanism(s) that requires the copper-responsive transcription factors Mac1 and AceI, copper superoxide dismutase (Sod1) activity, and the Rad53 checkpoint kinase. Furthermore, in copper-starved yeast, the response of the Rad53 pathway to MMS is compromised due to a loss of Sod1 activity, consistent with the model that yeast imports copper to ensure Sod1 activity and Rad53 signaling. Crucially, the Mac1 transcription factor undergoes changes in its redox state in response to changing levels of copper or MMS. This study has therefore identified a novel regulatory relationship between cellular redox, copper homeostasis, and the DNA damage response in yeast. PMID:23959798

  14. Alternative periplasmic copper-resistance mechanisms in Gram negative bacteria.

    PubMed

    Pontel, Lucas B; Soncini, Fernando C

    2009-07-01

    Bacteria have evolved different systems to tightly control both cytosolic and envelope copper concentration to fulfil their requirements and at the same time, avoid copper toxicity. We have previously demonstrated that, as in Escherichia coli, the Salmonella cue system protects the cytosol from copper excess. On the other hand, and even though Salmonella lacks the CusCFBA periplasmic copper efflux system, it can support higher copper concentrations than E. coli under anaerobic conditions. Here we show that the Salmonella cue regulon is also responsible for the control of copper toxicity in anaerobiosis. We establish that resistance in this condition requires a novel CueR-controlled gene named cueP. A DeltacueP mutant is highly susceptible to copper in the absence of oxygen, but shows a faint phenotype in aerobic conditions unless other copper-resistance genes are also deleted, resembling the E. coli CusCFBA behaviour. Species that contain a cueP homologue under CueR regulation have no functional CusR/CusS-dependent Cus-coding operon. Conversely, species that carry a CusR/CusS-regulated cus operon have no cueP homologues. Even more, we show that the CueR-controlled cueP expression increases copper resistance of a Deltacus E. coli. We posit that CueP can functionally replace the Cus complex for periplasmic copper resistance, in particular under anaerobic conditions.

  15. Copper as a key regulator of cell signalling pathways.

    PubMed

    Grubman, Alexandra; White, Anthony R

    2014-05-22

    Copper is an essential element in many biological processes. The critical functions associated with copper have resulted from evolutionary harnessing of its potent redox activity. This same property also places copper in a unique role as a key modulator of cell signal transduction pathways. These pathways are the complex sequence of molecular interactions that drive all cellular mechanisms and are often associated with the interplay of key enzymes including kinases and phosphatases but also including intracellular changes in pools of smaller molecules. A growing body of evidence is beginning to delineate the how, when and where of copper-mediated control over cell signal transduction. This has been driven by research demonstrating critical changes to copper homeostasis in many disorders including cancer and neurodegeneration and therapeutic potential through control of disease-associated cell signalling changes by modulation of copper-protein interactions. This timely review brings together for the first time the diverse actions of copper as a key regulator of cell signalling pathways and discusses the potential strategies for controlling disease-associated signalling processes using copper modulators. It is hoped that this review will provide a valuable insight into copper as a key signal regulator and stimulate further research to promote our understanding of copper in disease and therapy.

  16. Copper Tolerance and Biosorption of Saccharomyces cerevisiae during Alcoholic Fermentation.

    PubMed

    Sun, Xiang-Yu; Zhao, Yu; Liu, Ling-Ling; Jia, Bo; Zhao, Fang; Huang, Wei-Dong; Zhan, Ji-Cheng

    2015-01-01

    At high levels, copper in grape mash can inhibit yeast activity and cause stuck fermentations. Wine yeast has limited tolerance of copper and can reduce copper levels in wine during fermentation. This study aimed to understand copper tolerance of wine yeast and establish the mechanism by which yeast decreases copper in the must during fermentation. Three strains of Saccharomyces cerevisiae (lab selected strain BH8 and industrial strains AWRI R2 and Freddo) and a simple model fermentation system containing 0 to 1.50 mM Cu2+ were used. ICP-AES determined Cu ion concentration in the must decreasing differently by strains and initial copper levels during fermentation. Fermentation performance was heavily inhibited under copper stress, paralleled a decrease in viable cell numbers. Strain BH8 showed higher copper-tolerance than strain AWRI R2 and higher adsorption than Freddo. Yeast cell surface depression and intracellular structure deformation after copper treatment were observed by scanning electron microscopy and transmission electron microscopy; electronic differential system detected higher surface Cu and no intracellular Cu on 1.50 mM copper treated yeast cells. It is most probably that surface adsorption dominated the biosorption process of Cu2+ for strain BH8, with saturation being accomplished in 24 h. This study demonstrated that Saccharomyces cerevisiae strain BH8 has good tolerance and adsorption of Cu, and reduces Cu2+ concentrations during fermentation in simple model system mainly through surface adsorption. The results indicate that the strain selected from China's stress-tolerant wine grape is copper tolerant and can reduce copper in must when fermenting in a copper rich simple model system, and provided information for studies on mechanisms of heavy metal stress.

  17. Metabolism of manganese, iron, copper, and selenium in calves

    SciTech Connect

    Ho, S.Y.

    1981-01-01

    Sixteen male Holstein calves were used to study manganese and iron metabolism. The calves were fed one of the following diets for 18 days: control, control + iron, control + manganese, and control + iron and manganese. All calves were dosed orally with manganese-54. Tissue concentrations of manganese, iron and manganese-54 were determined. Small intestinal iron was lower in calves fed the high manganese diet than in controls. Tissue manganese-54 was lower in calves fed a high manganese diet. Fecal manganese content increased in calves fed both high manganese and high manganese-high iron diets. Serum total iron was not affected by the dietary treatments. To study the effects of high dietary levels of copper and selenium on the intracellular distributions of these two elements in liver and kidney cytosol, calves were fed one of four diets for 15 days. These were 0 and 100 ppM supplemental copper and 0 and 1 ppM added selenium. The control diet containing 0.1 ppM of selenium and 15 ppM of copper. All calves were orally dosed 48 hrs prior to sacrifice with selenium-75. A high copper diet increased copper concentrations in all intracellular liver fractions and most kidney fractions. Only the effects in the liver were significant. Less copper was found in the mitochondria fractions in liver and kidney of calves fed a high selenium diet. Three major copper-binding protein peaks were separated from the soluble fractions of calf liver and kidney. Peak 1 appeared to be the major copper-binding protein in liver and kidney cytosol of copper-loaded animals. Added selenium alone or in combination with copper accentuated the copper accumulation in this peak. Most of selenium-75 was recovered in the same peak as the copper. The results of this experiment indicated that the large molecular proteins in liver and kidney cytosol of calves play an important role in copper and selenium-75 metabolism. (ERB)

  18. Differential cytotoxicity of copper ferrite nanoparticles in different human cells.

    PubMed

    Ahmad, Javed; Alhadlaq, Hisham A; Alshamsan, Aws; Siddiqui, Maqsood A; Saquib, Quaiser; Khan, Shams T; Wahab, Rizwan; Al-Khedhairy, Abdulaziz A; Musarrat, Javed; Akhtar, Mohd Javed; Ahamed, Maqusood

    2016-10-01

    Copper ferrite nanoparticles (NPs) have the potential to be applied in biomedical fields such as cell labeling and hyperthermia. However, there is a lack of information concerning the toxicity of copper ferrite NPs. We explored the cytotoxic potential of copper ferrite NPs in human lung (A549) and liver (HepG2) cells. Copper ferrite NPs were crystalline and almost spherically shaped with an average diameter of 35 nm. Copper ferrite NPs induced dose-dependent cytotoxicity in both types of cells, evident by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide and neutral red uptake assays. However, we observed a quite different susceptibility in the two kinds of cells regarding toxicity of copper ferrite NPs. Particularly, A549 cells showed higher susceptibility against copper ferrite NP exposure than those of HepG2 cells. Loss of mitochondrial membrane potential due to copper ferrite NP exposure was observed. The mRNA level as well as activity of caspase-3 enzyme was higher in cells exposed to copper ferrite NPs. Cellular redox status was disturbed as indicated by induction of reactive oxygen species (oxidant) generation and depletion of the glutathione (antioxidant) level. Moreover, cytotoxicity induced by copper ferrite NPs was efficiently prevented by N-acetylcysteine treatment, which suggests that reactive oxygen species generation might be one of the possible mechanisms of cytotoxicity caused by copper ferrite NPs. To the best of our knowledge, this is the first report showing the cytotoxic potential of copper ferrite NPs in human cells. This study warrants further investigation to explore the mechanisms of differential toxicity of copper ferrite NPs in different types of cells. Copyright © 2016 John Wiley & Sons, Ltd.

  19. 78 FR 78727 - Copper Sulfate Pentahydrate; Exemption From the Requirement of a Tolerance

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-27

    ... establishes recommended daily allowances (RDAs) of vitamins and minerals for the diet. The RDA for copper... with the deficiency rather than the excess of copper. Oral ingestion of excessive amounts of the copper... deficiency of copper intake than from excess intake. Copper also occurs naturally in a number of food...

  20. 40 CFR 421.40 - Applicability: Description of the primary copper smelting subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... primary copper smelting subcategory. 421.40 Section 421.40 Protection of Environment ENVIRONMENTAL... CATEGORY Primary Copper Smelting Subcategory § 421.40 Applicability: Description of the primary copper... the primary smelting of copper from ore or ore concentrates. Primary copper smelting includes, but...