Preparation of high quality zirconium oxychloride from zircon of Vietnam

International Nuclear Information System (INIS)

Ngo Van Tuyen; Vu Thanh Quang; Trinh Giang Huong; Vuong Huu Anh

2007-01-01

This paper introduces a sodium hydroxide decomposition method for zirconium oxychloride production from zircon sand of Vietnam such as Ha Tinh, Hue, Binh Thuan seaside. Techniques for separation of impurities in ZOC final product such as SiO 2 , Fe 2 O 3 , TiO 2 , rare earths, uranium, and thorium have also been introduced. Content of uranium and thorium in the final product of ZOC is less than 1 ppm. (author)

Method to grow group III-nitrides on copper using passivation layers

Science.gov (United States)

Li, Qiming; Wang, George T; Figiel, Jeffrey T

2014-06-03

Group III-nitride epilayers can be grown directly on copper substrates using intermediate passivation layers. For example, single crystalline c-plane GaN can be grown on Cu (110) substrates with MOCVD. The growth relies on a low temperature AlN passivation layer to isolate any alloying reaction between Ga and Cu.

Improvement of oxidation resistance of copper by atomic layer deposition

Energy Technology Data Exchange (ETDEWEB)

Chang, M.L.; Cheng, T.C. [Department of Materials Science and Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 106, Taiwan (China); Lin, M.C. [Research Center for Biomedical Devices and Prototyping Production, Taipei Medical University, No. 250, Wu-Hsing Street, Taipei 110, Taiwan (China); Lin, H.C., E-mail: hclinntu@ntu.edu.tw [Department of Materials Science and Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 106, Taiwan (China); Chen, M.J., E-mail: mjchen@ntu.edu.tw [Department of Materials Science and Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 106, Taiwan (China)

2012-10-01

Graphical abstract: Results of glancing incident angle diffraction (GIXD) show the bare-Cu specimen was attacked by oxidation, whereas the coated-Cu specimens prevented from this problem. Highlights: Black-Right-Pointing-Pointer Deposition of Al{sub 2}O{sub 3} films on pure copper by an atomic layer deposition (ALD) technique. Black-Right-Pointing-Pointer Analysis of properties of the films coated at various substrate temperatures using the ALD technique. Black-Right-Pointing-Pointer Identification of the improvement of oxidation resistance of pure copper by the ALD-Al{sub 2}O{sub 3} films. Black-Right-Pointing-Pointer Assessment of the durability of the ALD-Al{sub 2}O{sub 3} films by adhesion strength. - Abstract: Al{sub 2}O{sub 3} films were deposited by the atomic layer deposition (ALD) technique onto pure copper at temperatures in the range 100-200 Degree-Sign C. The chemical composition, microstructure, and mechanic properties of the ALD-deposited Al{sub 2}O{sub 3} films were systematically analyzed. The variations in the film characteristics with substrate temperature were observed. Oxidation trials revealed that 20-nm-thick Al{sub 2}O{sub 3} films deposited at a substrate temperature as low as 100 Degree-Sign C suppress oxidative attack on pure copper. The Al{sub 2}O{sub 3} films also showed excellent durability of adhesion strength, according to predictions using the Coffin-Manson model based on the results of accelerated temperature cycling tests. These features indicate that ALD-deposited Al{sub 2}O{sub 3} film is a very promising candidate to be a protective coating for pure copper.

Transition layers formation on the boundaries carbon fiber-copper dependence on the active additions

International Nuclear Information System (INIS)

Wlosinski, W.; Pietrzak, K.

1993-01-01

The basic problem connected with fabrication of carbon fiber-copper composites is to overcome the problem of low wettability of carbon fiber by copper. One of the possible solutions of that problem is to use the copper doped with active metals. The investigation results of transition layer forming on the phase boundary in the system have been discussed in respect of the kind and content of active elements added to the copper. 5 refs, 5 figs, 5 tabs

Modelling of fast jet formation under explosion collision of two-layer alumina/copper tubes

Directory of Open Access Journals (Sweden)

I Balagansky

2017-09-01

Full Text Available Under explosion collapse of two-layer tubes with an outer layer of high-modulus ceramics and an inner layer of copper, formation of a fast and dense copper jet is plausible. We have performed a numerical simulation of the explosion collapse of a two-layer alumina/copper tube using ANSYS AUTODYN software. The simulation was performed in a 2D-axis symmetry posting on an Eulerian mesh of 3900x1200 cells. The simulation results indicate two separate stages of the tube collapse process: the nonstationary and the stationary stage. At the initial stage, a non-stationary fragmented jet is moving with the velocity of leading elements up to 30 km/s. The collapse velocity of the tube to the symmetry axis is about 2 km/s, and the pressure in the contact zone exceeds 700 GPa. During the stationary stage, a dense jet is forming with the velocity of 20 km/s. Temperature of the dense jet is about 2000 K, jet failure occurs when the value of effective plastic deformation reaches 30.

Structure of the Copper–Enriched Layer Introduced by Anodic Oxidation of Copper-Containing Aluminium Alloy

International Nuclear Information System (INIS)

Hashimoto, T.; Zhou, X.; Skeldon, P.; Thompson, G.E.

2015-01-01

This paper investigates the structure of the copper–enriched layer formed at the alloy/anodic film interface during anodizing of Al–2 wt.% Cu binary alloy using transmission electron microscopy. It was revealed that θ′ phase was formed within the copper–enriched layer. For the copper–enriched layer formed on {1 0 0} aluminum planes, the interface between the aluminum matrix and the θ′ phase within the copper-enriched layer is coherent. For the copper–enriched layer formed on {1 1 0} and {1 1 1} aluminum planes, the interfaces between the aluminum matrix and the θ′ phase within the copper-enriched layer are semi-coherent or incoherent. The interfacial coherency influences the formation of oxygen gas bubbles within the resultant anodic films.

Study on the CMP characteristics of a copper passivity layer formed by dipping in an oxidizer

International Nuclear Information System (INIS)

Choi, Youn-Ok; Lee, Woo-Sun; Choi, Gwon-Woo; Lee, Kang-Yeon; Kim, Nam-Oh

2011-01-01

Copper has been the material for ultra-large-scale integrated circuits owing to its excellent electromigration resistance and low electrical resistance. The polishing mechanism of metal chemical mechanical polishing (CMP) has been reported to be a repeated process of passive oxide layer formation through the use of on oxidizer and then the abrasion action of the slurry. However, because copper is softer and more sensitive to corrosion than tungsten, the slurry composition and the polishing mechanism during the copper CMP process may be more complicated. In a general Cu-CMP process, a mixture of an alumina-based slurry and an oxidizer in proper proportion is used in order to form a passive oxide layer such as CuO and CuO 2 . However, a conventional CMP process consumes an unnecessary amount of slurry to formed the passive layer. Therefore, in this paper, we propose a new method. The copper samples were oxidized by dipping in an oxidizer for an appropriate time to minimize the consumption of slurry before the CMP process. Then, we performed the CMP process. In order to compare the polishing characteristics of the copper thin film, we discuss the CMP removal rate and non-uniformity, as well as the microstructure of the surface and a layer cross-section based on a scanning.

Improvement of the adhesion strength between copper plated layer and resin substrate using a chemically adsorbed monolayer

Directory of Open Access Journals (Sweden)

Tsuchiya K.

2013-08-01

Full Text Available With reducing the size and weight of electric devices, high-tensile, light and fine copper wire is demanded. So the production technique of a copper wire plated on a super fiber resin (Vectran film was researched for improving the adhesion strength between the copper and the resin. In this study, we used the Cu2+ or Pd2+ complex prepared with a chemically adsorbed monolayer (CAM to improve the adhesion strength between the copper plated layer and the Vectran film. As the result of scotch tape test, it was observed that the adhesion strength between the copper plated layer and Vectran film was improved by the Cu2+ or Pd2+ complex CAM.

Facile synthesis of light harvesting semiconductor bismuth oxychloride nano photo-catalysts for efficient removal of hazardous organic pollutants.

Directory of Open Access Journals (Sweden)

Zaki S Seddigi

Full Text Available In the present work, bismuth oxychloride nanoparticles-a light harvesting semiconductor photocatalyst-were synthesized by a facile hydrolysis route, with sodium bismuthate and hydroxylammonium chloride as the precursor materials. The as-synthesized semiconductor photocatalysts were characterized using X-ray diffraction analysis, Fourier transform infra-red spectroscopy, Raman spectroscopy, Field emission scanning electron microscopy, X-ray photoelectron spectroscopy and Photoluminescence spectroscopy techniques. The crystal structure, morphology, composition, and optical properties of these facile synthesized bismuth oxychloride nanoparticles (BiOCl NPs were compared to those of traditional bismuth oxychloride. In addition, the photocatalytic performance of facile-synthesized BiOCl NPs and traditional BiOCl, as applied to the removal of hazardous organic dyes under visible light illumination, is thoroughly investigated. Our results reveal that facile-synthesized BiOCl NPs display strong UV-Vis light adsorption, improved charge carrier mobility and an inhibited rate of charge carrier recombination, when compared to traditional BiOCl. These enhancements result in an improved photocatalytic degradation rate of hazardous organic dyes under UV-Vis irradiance. For instance, the facile-synthesized BiOCl NPs attained 100% degradation of methylene blue and methyl orange dyes in approximately 30 mins under UV-Vis irradiation, against 55% degradation for traditional BiOCl under similar experimental conditions.

Facile synthesis of light harvesting semiconductor bismuth oxychloride nano photo-catalysts for efficient removal of hazardous organic pollutants.

Science.gov (United States)

Seddigi, Zaki S; Gondal, Mohammed A; Baig, Umair; Ahmed, Saleh A; Abdulaziz, M A; Danish, Ekram Y; Khaled, Mazen M; Lais, Abul

2017-01-01

In the present work, bismuth oxychloride nanoparticles-a light harvesting semiconductor photocatalyst-were synthesized by a facile hydrolysis route, with sodium bismuthate and hydroxylammonium chloride as the precursor materials. The as-synthesized semiconductor photocatalysts were characterized using X-ray diffraction analysis, Fourier transform infra-red spectroscopy, Raman spectroscopy, Field emission scanning electron microscopy, X-ray photoelectron spectroscopy and Photoluminescence spectroscopy techniques. The crystal structure, morphology, composition, and optical properties of these facile synthesized bismuth oxychloride nanoparticles (BiOCl NPs) were compared to those of traditional bismuth oxychloride. In addition, the photocatalytic performance of facile-synthesized BiOCl NPs and traditional BiOCl, as applied to the removal of hazardous organic dyes under visible light illumination, is thoroughly investigated. Our results reveal that facile-synthesized BiOCl NPs display strong UV-Vis light adsorption, improved charge carrier mobility and an inhibited rate of charge carrier recombination, when compared to traditional BiOCl. These enhancements result in an improved photocatalytic degradation rate of hazardous organic dyes under UV-Vis irradiance. For instance, the facile-synthesized BiOCl NPs attained 100% degradation of methylene blue and methyl orange dyes in approximately 30 mins under UV-Vis irradiation, against 55% degradation for traditional BiOCl under similar experimental conditions.

Dry air effects on the copper oxides sensitive layers formation for ethanol vapor detection

International Nuclear Information System (INIS)

Labidi, A.; Bejaoui, A.; Ouali, H.; Akkari, F. Chaffar; Hajjaji, A.; Gaidi, M.; Kanzari, M.; Bessais, B.; Maaref, M.

2011-01-01

The copper oxide films have been deposited by thermal evaporation and annealed under ambient air and dry air respectively, at different temperatures. The structural characteristics of the films were investigated by X-ray diffraction. They showed the presences of two hydroxy-carbonate minerals of copper for annealing temperatures below 250 deg. C. Above this temperature the conductivity measurements during the annealing process, show a transition phase from metallic copper to copper oxides. The copper oxides sensitivity toward ethanol were performed using conductivity measurements at the working temperature of 200 deg. C. A decrease of conductivity was observed under ethanol vapor, showing the p-type semi-conducting characters of obtained copper oxide films. It was found that the sensing properties of copper oxide toward ethanol depend mainly on the annealing conditions. The best responses were obtained with copper layers annealed under dry air.

Dry air effects on the copper oxides sensitive layers formation for ethanol vapor detection

Energy Technology Data Exchange (ETDEWEB)

Labidi, A., E-mail: Ahmed_laabidi@yahoo.fr [URPSC (UR 99/13-18) Unite de Recherche de Physique des Semiconducteurs et Capteurs, IPEST, Universite de Carthage, BP 51, La Marsa 2070, Tunis (Tunisia); Bejaoui, A.; Ouali, H. [URPSC (UR 99/13-18) Unite de Recherche de Physique des Semiconducteurs et Capteurs, IPEST, Universite de Carthage, BP 51, La Marsa 2070, Tunis (Tunisia); Akkari, F. Chaffar [Laboratoire de Photovoltaique et Materiaux Semi-conducteurs, ENIT, Universite de Tunis el Manar, BP 37, Le belvedere 1002, Tunis (Tunisia); Hajjaji, A.; Gaidi, M. [Laboratoire de Photovoltaique, Centre de Recherches et de technologies de l' energie, Technopole de Borj-Cedria, BP 95, 2050 Hammam-Lif (Tunisia); Kanzari, M. [Laboratoire de Photovoltaique et Materiaux Semi-conducteurs, ENIT, Universite de Tunis el Manar, BP 37, Le belvedere 1002, Tunis (Tunisia); Bessais, B. [Laboratoire de Photovoltaique, Centre de Recherches et de technologies de l' energie, Technopole de Borj-Cedria, BP 95, 2050 Hammam-Lif (Tunisia); Maaref, M. [URPSC (UR 99/13-18) Unite de Recherche de Physique des Semiconducteurs et Capteurs, IPEST, Universite de Carthage, BP 51, La Marsa 2070, Tunis (Tunisia)

2011-09-15

The copper oxide films have been deposited by thermal evaporation and annealed under ambient air and dry air respectively, at different temperatures. The structural characteristics of the films were investigated by X-ray diffraction. They showed the presences of two hydroxy-carbonate minerals of copper for annealing temperatures below 250 deg. C. Above this temperature the conductivity measurements during the annealing process, show a transition phase from metallic copper to copper oxides. The copper oxides sensitivity toward ethanol were performed using conductivity measurements at the working temperature of 200 deg. C. A decrease of conductivity was observed under ethanol vapor, showing the p-type semi-conducting characters of obtained copper oxide films. It was found that the sensing properties of copper oxide toward ethanol depend mainly on the annealing conditions. The best responses were obtained with copper layers annealed under dry air.

Light-weight wood-magnesium oxychloride cement composite building products made by extrusion

OpenAIRE

Zhou, X; Li, Z

2012-01-01

This is the post-print version of the final paper published in Construction and Building Materials. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2011 Elsevier B.V. Magnesium oxychloride (MOC) cement is ...

Effect of Mo Ion Implantation on Stability of Nanocrystalline Copper Surface Layers

Directory of Open Access Journals (Sweden)

XI Yang

2016-08-01

Full Text Available The surface of pure copper was modified using the surface mechanical attrition treatment (SMAT method, and molybdenum ions were implanted in the nanosurface using a metal vapor vacuum arc (MEVVA. The results of the SMAT were observed by optical microscopy (OM, X-ray diffraction (XRD and scanning electron microscopy (SEM. An obvious nanocrystalline layer and a deformation region exist on the surface. The size of the nanocrystalline layer was characterized using atomic force microscopy (AFM. The results indicate remarkable suppression on grain size, the nanocrystalline layer grows to 163nm after annealing and reduces to only 72nm due to the Mo ion implantation. In addition, the hardness of the topmost surface of the material is 3.5 times that of the SMATed copper, which is about 7 times of the value of the matrix. The above improvements most likely result from the dispersion of the Mo ions and the reactions of the crystal defects due to the SMAT and ion implantation.

Copper(II) Schiff base complexes and their mixed thin layers with ...

Indian Academy of Sciences (India)

Thin layer; ZnO nanoparticles; copper complexes; AFM; SEM; fluorescence. 1. Introduction ... ZnO nanopowders29,30 and ZnO nanoparticles doped by different metal ...... Roy S, Choubey S, Bhar K, Khan S, Mitra P and Ghosh. B K 2013 J. Mol ...

Thin films of copper oxide and copper grown by atomic layer deposition for applications in metallization systems of microelectronic devices

Energy Technology Data Exchange (ETDEWEB)

Waechtler, Thomas

2010-05-25

Copper-based multi-level metallization systems in today's ultralarge-scale integrated electronic circuits require the fabrication of diffusion barriers and conductive seed layers for the electrochemical metal deposition. Such films of only several nanometers in thickness have to be deposited void-free and conformal in patterned dielectrics. The envisaged further reduction of the geometric dimensions of the interconnect system calls for coating techniques that circumvent the drawbacks of the well-established physical vapor deposition. The atomic layer deposition method (ALD) allows depositing films on the nanometer scale conformally both on three-dimensional objects as well as on large-area substrates. The present work therefore is concerned with the development of an ALD process to grow copper oxide films based on the metal-organic precursor bis(trin- butylphosphane)copper(I)acetylacetonate [({sup n}Bu{sub 3}P){sub 2}Cu(acac)]. This liquid, non-fluorinated {beta}-diketonate is brought to react with a mixture of water vapor and oxygen at temperatures from 100 to 160 C. Typical ALD-like growth behavior arises between 100 and 130 C, depending on the respective substrate used. On tantalum nitride and silicon dioxide substrates, smooth films and selfsaturating film growth, typical for ALD, are obtained. On ruthenium substrates, positive deposition results are obtained as well. However, a considerable intermixing of the ALD copper oxide with the underlying films takes place. Tantalum substrates lead to a fast self-decomposition of the copper precursor. As a consequence, isolated nuclei or larger particles are always obtained together with continuous films. The copper oxide films grown by ALD can be reduced to copper by vapor-phase processes. If formic acid is used as the reducing agent, these processes can already be carried out at similar temperatures as the ALD, so that agglomeration of the films is largely avoided. Also for an integration with subsequent

Thin films of copper oxide and copper grown by atomic layer deposition for applications in metallization systems of microelectronic devices

Energy Technology Data Exchange (ETDEWEB)

Waechtler, Thomas

2010-05-25

Copper-based multi-level metallization systems in today's ultralarge-scale integrated electronic circuits require the fabrication of diffusion barriers and conductive seed layers for the electrochemical metal deposition. Such films of only several nanometers in thickness have to be deposited void-free and conformal in patterned dielectrics. The envisaged further reduction of the geometric dimensions of the interconnect system calls for coating techniques that circumvent the drawbacks of the well-established physical vapor deposition. The atomic layer deposition method (ALD) allows depositing films on the nanometer scale conformally both on three-dimensional objects as well as on large-area substrates. The present work therefore is concerned with the development of an ALD process to grow copper oxide films based on the metal-organic precursor bis(trin- butylphosphane)copper(I)acetylacetonate [({sup n}Bu{sub 3}P){sub 2}Cu(acac)]. This liquid, non-fluorinated {beta}-diketonate is brought to react with a mixture of water vapor and oxygen at temperatures from 100 to 160 C. Typical ALD-like growth behavior arises between 100 and 130 C, depending on the respective substrate used. On tantalum nitride and silicon dioxide substrates, smooth films and selfsaturating film growth, typical for ALD, are obtained. On ruthenium substrates, positive deposition results are obtained as well. However, a considerable intermixing of the ALD copper oxide with the underlying films takes place. Tantalum substrates lead to a fast self-decomposition of the copper precursor. As a consequence, isolated nuclei or larger particles are always obtained together with continuous films. The copper oxide films grown by ALD can be reduced to copper by vapor-phase processes. If formic acid is used as the reducing agent, these processes can already be carried out at similar temperatures as the ALD, so that agglomeration of the films is largely avoided. Also for an integration with subsequent

Micro-XRD Stress And Texture Study Of Inlaid Copper Lines - Influence Of ILD, Liner And Etch Stop Layer

International Nuclear Information System (INIS)

Prinz, H.; Zienert, I.; Rinderknecht, J.; Geisler, H.; Zschech, E.; Besser, P.

2004-01-01

The influence of ILD, liner and etch stop layer on the room temperature stress state of copper line test structures was examined by micro-XRD. Test structures consisted of large arrays of parallel lines with line widths of 0.18 μm and 1.8 μm. All these parameters have an influence on the room temperature stress state, whereas the variation of the liner and the ILD showed the largest effects. The change from a full low-k stack to a hybrid stack, where SiO2 ILD is use for the 'via layer' only and low-k material for the 'line layer' results in completely different parameter dependencies. The relationship between copper microstructure and the resulting stress in copper lines is discussed

Titania seed layers for PZT thin film growth on copper-coated Kapton films

Czech Academy of Sciences Publication Activity Database

Suchaneck, G.; Volkonskiy, O.; Hubička, Zdeněk; Dejneka, Alexandr; Jastrabík, Lubomír; Adolphi, B.; Bertram, M.; Gerlach, G.

2009-01-01

Roč. 108, č. 1 (2009), s. 57-66 ISSN 1058-4587 R&D Projects: GA ČR GC202/09/J017; GA AV ČR KJB100100703 Institutional research plan: CEZ:AV0Z10100522 Keywords : copper coated Kapton * seed layer * seed layer * plasma deposition * XPS Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.329, year: 2009

Investigation of magnesium oxychloride cement at the initial hardening stage

Directory of Open Access Journals (Sweden)

Averina Galina

2018-01-01

Full Text Available The paper investigates the process of variation of magnesium oxychloride cement deformations at the initial hardening stage depending on the activity of magnesium oxide powder which is determined by the parameters of the source material burning. Investigation is focused on magnesium cements obtained from pure magnesium hydroxide. Source materials were burnt at various temperatures with the purpose to obtain magnesium oxide powder with different activity. Regular content of hydrated phases was determined in hardened magnesium cement prepared on the basis of binders with different activity. The study reveals the influence of magnesium oxide powder activity on the process of deformation occurrence in hardened magnesium cement and its tendency to crack formation.

Low temperature plasma-enhanced atomic layer deposition of thin vanadium nitride layers for copper diffusion barriers

Energy Technology Data Exchange (ETDEWEB)

Rampelberg, Geert; Devloo-Casier, Kilian; Deduytsche, Davy; Detavernier, Christophe [Department of Solid State Sciences, Ghent University, Krijgslaan 281/S1, B-9000 Ghent (Belgium); Schaekers, Marc [IMEC, Kapeldreef 75, B-3001 Leuven (Belgium); Blasco, Nicolas [Air Liquide Electronics US, L.P., 46401 Landing Parkway, Fremont, California 94538 (United States)

2013-03-18

Thin vanadium nitride (VN) layers were grown by atomic layer deposition using tetrakis(ethylmethylamino)vanadium and NH{sub 3} plasma at deposition temperatures between 70 Degree-Sign C and 150 Degree-Sign C on silicon substrates and polymer foil. X-ray photoelectron spectroscopy revealed a composition close to stoichiometric VN, while x-ray diffraction showed the {delta}-VN crystal structure. The resistivity was as low as 200 {mu}{Omega} cm for the as deposited films and further reduced to 143 {mu}{Omega} cm and 93 {mu}{Omega} cm by annealing in N{sub 2} and H{sub 2}/He/N{sub 2}, respectively. A 5 nm VN layer proved to be effective as a diffusion barrier for copper up to a temperature of 720 Degree-Sign C.

Theoretical study of magnetic layers of nickel on copper; dead or alive?

Science.gov (United States)

Ernst, A.; Lueders, M.; Temmerman, W. M.; Szotek, Z.; van der Laan, G.

2000-07-01

We studied the persistence of magnetism in ultrathin nickel films on copper. Layer-dependent magnetic moments in Ni films on the (001), (110) and (111) surfaces of Cu have been calculated using the Korringa-Kohn-Rostoker Green's function method. The results show that, at temperature T = 0, a single nickel monolayer is ferromagnetic on Cu(001) and Cu(110) but magnetically `dead' on the more closely packed Cu(111) surface. Films of two and more layers of Ni are always ferromagnetic, with the magnetic moment enhanced in the surface layer but strongly reduced in the interface layer. Due to the short screening length, both the effect of the interface and that of the surface are confined to only a few atomic layers.

Effect of native oxide layers on copper thin-film tensile properties: A reactive molecular dynamics study

Energy Technology Data Exchange (ETDEWEB)

Skarlinski, Michael D., E-mail: michael.skarlinski@rochester.edu [Materials Science Program, University of Rochester, Rochester, New York 14627 (United States); Quesnel, David J. [Materials Science Program, University of Rochester, Rochester, New York 14627 (United States); Department of Mechanical Engineering, University of Rochester, Rochester, New York 14627 (United States)

2015-12-21

Metal-oxide layers are likely to be present on metallic nano-structures due to either environmental exposure during use, or high temperature processing techniques such as annealing. It is well known that nano-structured metals have vastly different mechanical properties from bulk metals; however, difficulties in modeling the transition between metallic and ionic bonding have prevented the computational investigation of the effects of oxide surface layers. Newly developed charge-optimized many body [Liang et al., Mater. Sci. Eng., R 74, 255 (2013)] potentials are used to perform fully reactive molecular dynamics simulations which elucidate the effects that metal-oxide layers have on the mechanical properties of a copper thin-film. Simulated tensile tests are performed on thin-films while using different strain-rates, temperatures, and oxide thicknesses to evaluate changes in yield stress, modulus, and failure mechanisms. Findings indicate that copper-thin film mechanical properties are strongly affected by native oxide layers. The formed oxide layers have an amorphous structure with lower Cu-O bond-densities than bulk CuO, and a mixture of Cu{sub 2}O and CuO charge character. It is found that oxidation will cause modifications to the strain response of the elastic modulii, producing a stiffened modulii at low temperatures (<75 K) and low strain values (<5%), and a softened modulii at higher temperatures. While under strain, structural reorganization within the oxide layers facilitates brittle yielding through nucleation of defects across the oxide/metal interface. The oxide-free copper thin-film yielding mechanism is found to be a tensile-axis reorientation and grain creation. The oxide layers change the observed yielding mechanism, allowing for the inner copper thin-film to sustain an FCC-to-BCC transition during yielding. The mechanical properties are fit to a thermodynamic model based on classical nucleation theory. The fit implies that the oxidation of the

Characterization of hafnium oxide resistive memory layers deposited on copper by atomic layer deposition

Energy Technology Data Exchange (ETDEWEB)

Briggs, B.D.; Bishop, S.M. [SUNY College of Nanoscale Science and Engineering, 255 Fuller Road, Albany, NY 12203 (United States); Leedy, K.D. [Air Force Research Laboratory, 2241 Avionics Circle, Wright Patterson Air Force Base, Dayton, OH 45433 (United States); Cady, N.C., E-mail: ncady@albany.edu [SUNY College of Nanoscale Science and Engineering, 255 Fuller Road, Albany, NY 12203 (United States)

2014-07-01

Hafnium oxide-based resistive memory devices have been fabricated on copper bottom electrodes. The HfO{sub x} active layers in these devices were deposited by atomic layer deposition (ALD) at 250 °C with tetrakis(dimethylamido)hafnium(IV) as the metal precursor and an O{sub 2} plasma as the reactant. Depth profiles of the HfO{sub x} by X-ray photoelectron spectroscopy and secondary ion mass spectroscopy revealed a copper concentration on the order of five atomic percent throughout the HfO{sub x} film. In addition to the Cu doped HfO{sub x}, a thin layer (20 nm) of Cu{sub x}O is present at the surface. This surface layer is believed to have formed during the ALD process, and greatly complicates the analysis of the switching mechanism. The resistive memory structures fabricated from the ALD HfO{sub x} exhibited non-polar resistive switching, independent of the top metal electrode (Ni, Pt, Al, Au). Resistive switching current voltage (I–V) curves were analyzed using Schottky emission and ionic hopping models to gain insight into the physical mechanisms underpinning the device behavior. During the forming process it was determined that, at voltages in excess of 2.5 V, an ionic hopping model is in good agreement with the I–V data. The extracted ion hopping distance ∼ 4 Å was within the range of interatomic spacing of HfO{sub 2} during the forming process consistent with ionic motion of Cu{sup 2+} ions. Lastly the on state I–V data was dominated at larger voltages by Schottky emission with an estimated barrier height of ∼ 0.5 eV and a refractive index of 2.59. The consequence of the Schottky emission analysis indicates the on state resistance to be a product of a Pt/Cu{sub 2}O/Cu filament(s)/Cu{sub 2}O/Cu structure. - Highlights: • HfO{sub 2} was grown via atomic layer deposition at 250 and 100 °C on Cu substrates. • A Cu{sub 2}O surface layer and Cu doping were observed in post-deposition of HfO{sub 2}. • Resistive memory devices were fabricated and

Suspension Flame Spray Construction of Polyimide-Copper Layers for Marine Antifouling Applications

Science.gov (United States)

Liu, Yi; Xu, Xiaomin; Suo, Xinkun; Gong, Yongfeng; Li, Hua

2018-01-01

Individual capsule-like polyimide splats have been fabricated by suspension flame spray, and the polyimide splat exhibits hollow structure with an inner pore and a tiny hole on its top surface. Enwrapping of 200-1000-nm copper particles inside the splats is accomplished during the deposition for constrained release of copper for antifouling performances. Antifouling testing of the coatings by 24-h exposure to Escherichia coli-containing artificial seawater shows that the Cu-doped splat already prohibits effectively attachment of the bacteria. The prohibited adhesion of bacteria obviously impedes formation and further development of bacterial biofilm. This capsulated splat with releasing and loading of copper biocides results in dual-functional structures bearing both release-killing and contact-killing mechanisms. The suspension flame spray route and the encapsulated structure of the polyimide-Cu coatings would open a new window for designing and constructing marine antifouling layers for long-term applications.

Evaluation of grapefruit seed extract as natural fungicide to control apple scab in organic apple growing

OpenAIRE

Trapman, Marc

2004-01-01

C-pro, an experimental fungicide based on grapefruit seed extract was compared to copper oxychloride for the control of apple scab in a field trial. Efficacy and possible phytotoxic effects where accessed. The C-pro formulation was analysed for possible chemical additives by HPTLC. C-pro proved tot be more effective in controlling apple scab then the standard rate of 300 gram copper oxychloride per ha, and gave a better leaf quality and less fruit skin russeting then the sta...

pH-regulated antimony oxychloride nanoparticle formation on titanium oxide nanostructures: a photocatalytically active heterojunction

KAUST Repository

Buchholcz, Balázs

2017-02-06

Improving the catalytic activity of heterogeneous photocatalysts has become a hot topic recently. To this end, considerable progress has been made in the efficient separation of photogenerated charge carriers by e.g. the realization of heterojunction photocatalysts. V-VI-VII compound semiconductors, namely, bismuth oxyhalides, are popular photocatalysts. However, results on antimony oxyhalides [SbOX (X = Br, Cl, I)], the very promising alternatives to the well-known BiOX photomodifiers, are scarce. Here, we report the successful decoration of titanium oxide nanostructures with 8-11 nm diameter SbOX nanoparticles for the first time ever. The product size and stoichiometry could be controlled by the pH of the reactant mixture, while subsequent calcination could transform the structure of the titanate nanotube (TiONT) support and the prepared antimony oxychloride particles. In contrast to the ease of composite formation in the SbOX/TiONT case, anatase TiO could not facilitate the formation of antimony oxychloride nanoparticles on its surface. The titanate nanotube-based composites showed activity in a generally accepted quasi-standard photocatalytic test reaction (methyl orange dye decolorization). We found that the SbOCl/TiONT synthesized at pH = 1 is the most active sample in a broad temperature range.

A Water Model Study on Mixing Behavior of the Two-Layered Bath in Bottom Blown Copper Smelting Furnace

Science.gov (United States)

Shui, Lang; Cui, Zhixiang; Ma, Xiaodong; Jiang, Xu; Chen, Mao; Xiang, Yong; Zhao, Baojun

2018-05-01

The bottom-blown copper smelting furnace is a novel copper smelter developed in recent years. Many advantages of this furnace have been found, related to bath mixing behavior under its specific gas injection scheme. This study aims to use an oil-water double-phased laboratory-scale model to investigate the impact of industry-adjustable variables on bath mixing time, including lower layer thickness, gas flow rate, upper layer thickness and upper layer viscosity. Based on experimental results, an overall empirical relationship of mixing time in terms of these variables has been correlated, which provides the methodology for industry to optimize mass transfer in the furnace.

Characteristics of organic light emitting diodes with copper iodide as injection layer

Energy Technology Data Exchange (ETDEWEB)

Stakhira, P., E-mail: stakhira@polynet.lviv.u [Lviv Polytechnic National University, S. Bandera, 12, Lviv, 79013 (Ukraine); Cherpak, V.; Volynyuk, D.; Ivastchyshyn, F. [Lviv Polytechnic National University, S. Bandera, 12, Lviv, 79013 (Ukraine); Hotra, Z. [Lviv Polytechnic National University, S. Bandera, 12, Lviv, 79013 (Ukraine); Rzeszow University of Technology, W. Pola 2, Rzeszow, 35-959 (Poland); Tataryn, V. [Lviv Polytechnic National University, S. Bandera, 12, Lviv, 79013 (Ukraine); Luka, G. [Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw (Poland)

2010-09-30

We have studied the use of a thin copper iodide (CuI) film as an efficient injection layer of holes from indium tin oxide (ITO) anode in a light-emitting diode structure based on tris-8-hydroxyquinoline aluminium (Alq3). The results of impedance analysis of two types of diode structures, ITO/CuI/Alq3/poly(ethylene glycol) dimethyl ether/Al and ITO/Alq3/poly(ethylene glycol) dimethyl ether/Al, are presented. Comparative analysis of their current density-voltage, luminance-voltage and impedance characteristics shows that presence of CuI layer facilitates injection of holes from ITO anode into the light-emitting layer Alq3 and increases electroluminescence efficiency of the organic light emitting diodes.

ENVIRONMENTAL RISK ASSESSMENT OF SOME COPPER BASED FUNGICIDES ACCORDING TO THE REQUIREMENTS OF GOOD LABORATORY PRACTICE

Directory of Open Access Journals (Sweden)

Marga GRĂDILĂ

2015-10-01

Full Text Available The paper presents data demonstrating the functionality of biological systems reconstituted with aquatic organisms developed under Good Laboratory Practice testing facility within Research - Development Institute for Plant Protection Bucharest for environmental risk assessment of four fungicides based on copper, according to Good Laboratory Practice requirements. For risk assessment, according to GLP were made the following steps: Good Laboratory Practice test facility was established, we have ensured adequate space for growth, acclimatization and testing for each test species, it was installed a complex water production instalation needed to perform tests, it was achieved control system for checking environmental conditions and have developed specific operating procedures that have been accredited according to Good Laboratory Practice.The results showed that biological systems model of the Good Laboratory Practice test facility in Research - Development Institute for Plant Protection meet the requirements of Organisation for Economic Co-operation and Development Guidelines regarding GLP, and after testing copper-based fungicides in terms of acute toxicity Cyprinus carpio and to Daphnia magna revealed that three of them (copper oxychloride, copper hydroxide and copper sulphate showed ecological efficiency, ie low toxicity. Metallic copper based fungicides showed a higher toxicity, resulting in fish toxicity symptoms: sleep, sudden immersion, faded, weakness, swimming in spiral, lack of balance, breathing slow and cumbersome, spasms and mortality.

Layered copper hydroxide n-alkylsulfonate salts: synthesis, characterization, and magnetic behaviors in relation to the basal spacing.

Science.gov (United States)

Park, Seong-Hun; Lee, Cheol Eui

2005-01-27

A series of hybrid inorganic-organic copper(II) hydroxy n-alkylsulfonate with a triangular lattice, Cu(2)(OH)(3)(C(n)H(2)(n)(+1)SO(3)) (n = 6, 8, 10), are prepared by anion exchange, starting from copper hydroxy nitrate Cu(2)(OH)(3)NO(3). These compounds show a layered structure as determined by X-ray diffraction, with interlayer distances of 14.3-34.8 A in alternation with interdigitated bilayer packing. Magnetic properties have been investigated by means of dc and ac measurements. All the compounds show similar metamagnet behaviors, with a Neel temperature of about 11 K. A subtle difference in the ac magnetic susceptibility among the compounds is understood by the existence of hydrogen bonding between the sulfonate headgroup and the hydroxide anion. A detailed molecular structure of the alkyl chains incorporated to the inorganic copper hydroxide layer is also discussed from the FTIR data.

Method for providing uranium with a protective copper coating

Science.gov (United States)

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.

X-ray spectrum microanalysis of copper and stainless steel surface layer after electroerosion machining

International Nuclear Information System (INIS)

Abdukarimov, Eh.T.; Saidinov, S.Ya.

1989-01-01

The results of experimental investigations of the surface layer of copper and steel 12Kh18N10T after electroerrosion treatment by a rotating tungsten electrode in natural and distilled water are presented. It is established that the quantity of electrode material transferred to the surface of the steel treated grows with the spark discharge energy increase. Tungsten concentration in the surface layer reaches 5-10% with the average depth of penetration 40-50 μm

Atomic layer deposition of copper thin film and feasibility of deposition on inner walls of waveguides

Science.gov (United States)

Yuqing, XIONG; Hengjiao, GAO; Ni, REN; Zhongwei, LIU

2018-03-01

Copper thin films were deposited by plasma-enhanced atomic layer deposition at low temperature, using copper(I)-N,N‧-di-sec-butylacetamidinate as a precursor and hydrogen as a reductive gas. The influence of temperature, plasma power, mode of plasma, and pulse time, on the deposition rate of copper thin film, the purity of the film and the step coverage were studied. The feasibility of copper film deposition on the inner wall of a carbon fibre reinforced plastic waveguide with high aspect ratio was also studied. The morphology and composition of the thin film were studied by atomic force microscopy and x-ray photoelectron spectroscopy, respectively. The square resistance of the thin film was also tested by a four-probe technique. On the basis of on-line diagnosis, a growth mechanism of copper thin film was put forward, and it was considered that surface functional group played an important role in the process of nucleation and in determining the properties of thin films. A high density of plasma and high free-radical content were helpful for the deposition of copper thin films.

The use of aluminum oxychlorides to coagulate water having high content of organic impurities and low alkalinity

Science.gov (United States)

Evsyutin, A. V.; Boglovskii, A. V.

2007-07-01

Results from laboratory investigations and industrial tests of the coagulation of source water at the Pskov district power station are presented. It is shown that the source water may not be alkalified if it is treated with aluminum oxychlorides. As a result, the clarified water becomes less corrosive and a lower salt load is placed on water treatment plants as compared with the case when aluminum sulfate is used for coagulation.

Layer-by-layer self-assembling copper tetrasulfonated phthalocyanine on carbon nanotube modified glassy carbon electrode for electro-oxidation of 2-mercaptoethanol

International Nuclear Information System (INIS)

Shaik, Mahabul; Rao, V.K.; Gupta, Manish; Pandey, P.

2012-01-01

This paper describes the electrocatalytic activity of layer-by-layer self-assembled copper tetrasulfonated phthalocyanine (CuPcTS) on carbon nanotube (CNT)-modified glassy carbon (GC) electrode. CuPcTS is immobilized on the negatively charged CNT surface by alternatively assembling a cationic poly(diallyldimethylammonium chloride) (PDDA) layer and a CuPcTS layer. UV–vis absorption spectra and electrochemical measurements suggested the successive linear depositions of the bilayers of CuPcTs and PDDA on CNT. The surface morphology was observed using scanning electron microscopy. The viability of this CuPcTS/PDDA/CNT modified GC electrode as a redox mediator for the anodic oxidation and sensitive amperometric determination of 2-mercaptoethanol (2-ME) in alkaline conditions is described. The effect of number of bilayers of CuPcTS/PDDA and pH on electrochemical oxidation of 2-ME was studied. The proposed electrochemical sensor displayed excellent characteristics towards the determination of 2-ME in 0.1 M NaOH; such as low overpotentials (− 0.15 V vs Ag/AgCl), linear concentration range of 3 × 10 −5 M to 6 × 10 −3 M, and with a detection limit of 2.5 × 10 −5 M using simple amperometry. - Highlights: ► Carbon nanotubes (CNT) were drop-dried on glassy carbon electrode (GCE). ► Copper tetrasulfonated phthalocyanine (CuPcTS) was deposited on CNT/GCE. ► Layer-by-layer self-assembling method is used for depositing CuPcTS. ► Electrocatalytic oxidation of 2-mercaptoethanol (ME) was studied at this electrode ► The detection limit of ME at modified electrode was 25 μM by amperometry.

Study of lanthanum, yttrium and erbium oxychlorides in melts of alkali metal chlorides

International Nuclear Information System (INIS)

Gamanovich, N.M.; Glybin, V.P.; Dobrotin, R.B.

1977-01-01

The system MeCl-(La,Y)OCl (Me=Li,Na,K,Rb,Cs) and MeCl-ErOCl (Me=Li,Rb,Cs) have been studied by the methods of differential-thermal and X-ray phase analyses. The system NaCl-LaOCl has been studied by cryoscopic method as well. It has been established that the systems refer to the type of fusibility diagrams with a simple eutectics. A comparison of the fusibility diagrams with calculations for ideal systems, under the assumption that the association degree of ions is different, makes it possible to assume a considerable polymerizations degree of oxychloride in the melts MeCl-(Y,Er)OCl

Effect of oxide insertion layer on resistance switching properties of copper phthalocyanine

Science.gov (United States)

Joshi, Nikhil G.; Pandya, Nirav C.; Joshi, U. S.

2013-02-01

Organic memory device showing resistance switching properties is a next-generation of the electrical memory unit. We have investigated the bistable resistance switching in current-voltage (I-V) characteristics of organic diode based on copper phthalocyanine (CuPc) film sandwiched between aluminum (Al) electrodes. Pronounced hysteresis in the I-V curves revealed a resistance switching with on-off ratio of the order of 85%. In order to control the charge injection in the CuPc, nanoscale indium oxide buffer layer was inserted to form Al/CuPc/In2O3/Al device. Analysis of I-V measurements revealed space charge limited switching conduction at the Al/CuPc interface. The traps in the organic layer and charge blocking by oxide insertion layer have been used to explain the absence of resistance switching in the oxide buffer layered memory device cell. Present study offer potential applications for CuPc organic semiconductor in low power non volatile resistive switching memory and logic circuits.

An RBS study of thin PLD and MOCVD strontium copper oxide layers

Energy Technology Data Exchange (ETDEWEB)

Kantor, Z. [Institute of Physics, University of Pannonia, H-8200 Veszprem (Hungary); Papadopoulou, E.L.; Aperathitis, E. [Inst. Electronic Struture and Laser, Foundation for Research and Technology - Hellas, P.O. Box 1527, Heraklion 71110 (Greece); Deschanvres, J.-L. [LMPG INP Grenoble-Minatec, BP 257, 38016 Grenoble Cedex 1 (France); Somogyi, K. [MicroVacuum Ltd., Kerekgyarto u.: 10, H-1147 Budapest (Hungary)], E-mail: karoly.somogyi@microvacuum.com; Szendro, I. [MicroVacuum Ltd., Kerekgyarto u.: 10, H-1147 Budapest (Hungary)

2008-09-30

Strontium copper oxide (SCO) has been studied as p-type transparent (VIS) conductive oxide material. Also theoretical studies suggested p-type conductivity of the SrCu{sub 2}O{sub 2} composition. SCO thin layers, with thicknesses of 30-2000 nm, were deposited on glass and silicon substrates both by pulsed laser deposition (PLD) and by MOCVD method. The as-grown layers showed high electrical resistance. Due to an annealing process, the resistivity significantly decreased and the layers showed p-type conductivity. Optical transparency measured on samples grown on glass substrates was found about or above 80%, including also thickness dependence. RBS measurements were applied for the determination of the chemical composition profile of the layers. A comparison revealed some specific differences between as-grown and annealed PLD samples. Due to the annealing, the ratio of oxide phases was changed and a vertical inhomogeneity in chemical composition was observed. Our measurements revealed also the influence of the deposition technique and of the substrate.

A copper-based layered coordination polymer: synthesis, magnetic properties and electrochemical performance in supercapacitors.

Science.gov (United States)

Liu, Qi; Liu, Xiuxiu; Shi, Changdong; Zhang, Yanpeng; Feng, Xuejun; Cheng, Mei-Ling; Su, Seng; Gu, Jiande

2015-11-28

A copper-based layered coordination polymer ([Cu(hmt)(tfbdc)(H2O)]; hmt = hexamethylenetetramine, tfbdc = 2,3,5,6-tetrafluoroterephthalate; Cu-LCP) has been synthesized, and it has been structurally and magnetically characterized. The Cu-LCP shows ferromagnetic interactions between the adjacent copper(II) ions. Density functional theory calculations on the special model of Cu-LCP support the occurrence of ferromagnetic interactions. As an electrode material for supercapacitors, Cu-LCP exhibits a high specific capacitance of 1274 F g(-1) at a current density of 1 A g(-1) in 1 M LiOH electrolyte, and the capacitance retention is about 88% after 2000 cycles.

Investigation of zirconium oxychloride interaction with acetylacetone by the method of pH-metric titration

International Nuclear Information System (INIS)

Zharkova, N.Ya.; Martynenko, L.I.; Dzyubenko, N.G.

1989-01-01

Interaction of zirconium oxychloride with acetylacetone (NA) was studied by the method of pH-metric titration using KOH and NH 4 OH as neutralizing agents. It is shown that processes of hydrolysis and complexation complete in the system. It was established that decrease of hydrolysis of Zr-containing complex forms and ZrA 4 · 10H 2 O isolation takes place in relatively concentrated solutions of ZrOCl 2 and NA mixture, taken with 1:4 molar ratio when using NH 4 OH as neutralizing agent

Immobilization of industrial waste in cement–bentonite clay matrix

Indian Academy of Sciences (India)

Results of a series of experimental tests performed to determine the influence of matrix characteristics on the leaching mechanism of copper aluminum oxychloride immobilized into cement matrices are presented. The objective of this work was to investigate the leaching mechanism of copper as a constituent of copper ...

Adsorption of copper to different biogenic oyster shell structures

Energy Technology Data Exchange (ETDEWEB)

Wu, Qiong; Chen, Jie [College of Materials Science and Engineering, Fuzhou University, New Campus, Minhou, Fujian Province 350108 (China); Clark, Malcolm [Marine Ecology Research Centre, School of Environment, Science and Engineering, Southern Cross University, P.O. Box 157, Lismore, NSW 2480 (Australia); Yu, Yan, E-mail: yuyan_1972@126.com [College of Materials Science and Engineering, Fuzhou University, New Campus, Minhou, Fujian Province 350108 (China)

2014-08-30

Graphical abstract: - Highlights: • Adsorption of copper to waste oyster shell occurs rapidly at pH 5.5. • Copper adsorbs to the different structures of oyster shell at different rates. • The prismatic layer dominates copper sorption rather than the nacreous layer. • SEM analysis shows a porous open network structure to the prismatic layer. • Surface ζ-potentials establish electrostatic attraction to drive copper sorption. - Abstract: The removal of copper from solution by oyster shell powder was investigated for potential wastewater treatment uses. In particular, adsorption behavior differences between the prismatic (PP) and nacreous (NP) shell layers, and how this affects copper removal, were investigated. Experimental results indicated that copper adsorption was highly pH-dependent with optimal copper removal at pH 5.5, where the powdered whole raw shell (RP) removed up to 99.9% of the copper within 24 h at a 10 mg/L initial copper concentration. Langmuir and Freundlich models were used to analyze the isotherm PP, NP and RP data. These results showed a strong homogeneous Langmuir model for low initial copper concentrations (5–30 mg/L) to both RP and PP layer, while strong agreement with a heterogeneous Freundlich model for high initial copper concentrations (30–200 mg/L); nevertheless, a homogeneous Langmuir model provided the best fit for the more dense NP layer across the initial concentration range (5–200 mg/L). The distribution coefficient (K{sub d}) value of PP layer for each initial concentration investigated was substantially higher than the NP layer and it was also found that the PP layer dominated the adsorption process with an adsorption capacity of 8.9 mg/g, while the adsorption capacity of the NP layer was 2.6 mg/g. These differences are believed to be because of the more porous structure of the PP layer, which was confirmed by scanning electron microscopy, infrared spectroscopy, energy-dispersive X-ray spectroscopy, and

Adsorption of copper to different biogenic oyster shell structures

International Nuclear Information System (INIS)

Wu, Qiong; Chen, Jie; Clark, Malcolm; Yu, Yan

2014-01-01

Graphical abstract: - Highlights: • Adsorption of copper to waste oyster shell occurs rapidly at pH 5.5. • Copper adsorbs to the different structures of oyster shell at different rates. • The prismatic layer dominates copper sorption rather than the nacreous layer. • SEM analysis shows a porous open network structure to the prismatic layer. • Surface ζ-potentials establish electrostatic attraction to drive copper sorption. - Abstract: The removal of copper from solution by oyster shell powder was investigated for potential wastewater treatment uses. In particular, adsorption behavior differences between the prismatic (PP) and nacreous (NP) shell layers, and how this affects copper removal, were investigated. Experimental results indicated that copper adsorption was highly pH-dependent with optimal copper removal at pH 5.5, where the powdered whole raw shell (RP) removed up to 99.9% of the copper within 24 h at a 10 mg/L initial copper concentration. Langmuir and Freundlich models were used to analyze the isotherm PP, NP and RP data. These results showed a strong homogeneous Langmuir model for low initial copper concentrations (5–30 mg/L) to both RP and PP layer, while strong agreement with a heterogeneous Freundlich model for high initial copper concentrations (30–200 mg/L); nevertheless, a homogeneous Langmuir model provided the best fit for the more dense NP layer across the initial concentration range (5–200 mg/L). The distribution coefficient (K d ) value of PP layer for each initial concentration investigated was substantially higher than the NP layer and it was also found that the PP layer dominated the adsorption process with an adsorption capacity of 8.9 mg/g, while the adsorption capacity of the NP layer was 2.6 mg/g. These differences are believed to be because of the more porous structure of the PP layer, which was confirmed by scanning electron microscopy, infrared spectroscopy, energy-dispersive X-ray spectroscopy, and

Method for aluminium dross utilization

International Nuclear Information System (INIS)

Lucheva, B.; Petkov, R.; Tzonev, Tz.

2003-01-01

A new hydrometallurgical method has been developed for metal aluminum utilization from secondary aluminum dross. Secondary aluminum dross is a powder product with an average of 35% aluminium content (below 1mm). It is waste from primary aluminum dross pyrometallurgical flux less treatment in rotary DC electric arc furnace. This method is based on aluminum leaching in copper chloride water solution. As a result an aluminum oxychloride solution and solids, consisting of copper and oxides are obtained. In order to copper chloride solution regenerate hydrochloric acid is added to the solids. The process is simple, quick, economic and safe. The aluminum oxychloride solution contains 56 g/l Al 2 O 3 . The molar ratios are Al:Cl=0,5; OH:Al=1. The solution has 32 % basicity and 1,1 g/cm 3 density. For increasing the molar ratio of aluminium to chlorine aluminum hydroxide is added to this solution at 80 o C. Aluminum hydroxide is the final product from the secondary aluminum dross alkaline leaching. As a result aluminum oxychloride solution of the following composition is prepared: Al 2 O 3 - 180 g/l; Al:Cl=1,88; OH:Al=4,64; basicity 82%; density 1,22 g/cm 3 , pH=4 -4,5. Aluminum oxychloride solution produced by means of this method can be used in potable and wastewater treatment, paper making, in refractory mixture as a binder etc. (Original)

Copper diffusion in Ti-Si-N layers formed by inductively coupled plasma implantation

International Nuclear Information System (INIS)

Ee, Y.C.; Chen, Z.; Law, S.B.; Xu, S.; Yakovlev, N.L.; Lai, M.Y.

2006-01-01

Ternary Ti-Si-N refractory barrier films of 15 nm thick was prepared by low frequency, high density, inductively coupled plasma implantation of N into Ti x Si y substrate. This leads to the formation of Ti-N and Si-N compounds in the ternary film. Diffusion of copper in the barrier layer after annealing treatment at various temperatures was investigated using time-of-flight secondary ion mass spectrometer (ToF-SIMS) depth profiling, X-ray diffractometer (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) and sheet resistance measurement. The current study found that barrier failure did not occur until 650 deg. C annealing for 30 min. The failure occurs by the diffusion of copper into the Ti-Si-N film to form Cu-Ti and Cu-N compounds. FESEM surface morphology and EDX show that copper compounds were formed on the ridge areas of the Ti-Si-N film. The sheet resistance verifies the diffusion of Cu into the Ti-Si-N film; there is a sudden drop in the resistance with Cu compound formation. This finding provides a simple and effective method of monitoring Cu diffusion in TiN-based diffusion barriers

Efficient organic solar cells using copper(I) iodide (CuI) hole transport layers

Energy Technology Data Exchange (ETDEWEB)

Peng, Ying [Key Laboratory of Luminescence and Optical Information, Ministry of Education, Institute of Optoelectronic Technology, Beijing Jiaotong University, Beijing 100044 (China); Department of Physics and Centre for Plastic Electronics, Blackett Laboratory, Imperial College London, London SW7 2AZ (United Kingdom); Yaacobi-Gross, Nir; Perumal, Ajay K.; Faber, Hendrik A.; Bradley, Donal D. C.; Anthopoulos, Thomas D., E-mail: zhqhe@bjtu.edu.cn, E-mail: t.anthopoulos@imperial.ac.uk [Department of Physics and Centre for Plastic Electronics, Blackett Laboratory, Imperial College London, London SW7 2AZ (United Kingdom); Vourlias, George; Patsalas, Panos A. [Department of Physics, Laboratory of Applied Physics, Aristotle University of Thessaloniki, GR-54124 Thessaloniki (Greece); He, Zhiqun, E-mail: zhqhe@bjtu.edu.cn, E-mail: t.anthopoulos@imperial.ac.uk [Key Laboratory of Luminescence and Optical Information, Ministry of Education, Institute of Optoelectronic Technology, Beijing Jiaotong University, Beijing 100044 (China)

2015-06-15

We report the fabrication of high power conversion efficiency (PCE) polymer/fullerene bulk heterojunction (BHJ) photovoltaic cells using solution-processed Copper (I) Iodide (CuI) as hole transport layer (HTL). Our devices exhibit a PCE value of ∼5.5% which is equivalent to that obtained for control devices based on the commonly used conductive polymer poly(3,4-ethylenedioxythiophene): polystyrenesulfonate as HTL. Inverted cells with PCE >3% were also demonstrated using solution-processed metal oxide electron transport layers, with a CuI HTL evaporated on top of the BHJ. The high optical transparency and suitable energetics of CuI make it attractive for application in a range of inexpensive large-area optoelectronic devices.

Efficient organic solar cells using copper(I) iodide (CuI) hole transport layers

International Nuclear Information System (INIS)

Peng, Ying; Yaacobi-Gross, Nir; Perumal, Ajay K.; Faber, Hendrik A.; Bradley, Donal D. C.; Anthopoulos, Thomas D.; Vourlias, George; Patsalas, Panos A.; He, Zhiqun

2015-01-01

We report the fabrication of high power conversion efficiency (PCE) polymer/fullerene bulk heterojunction (BHJ) photovoltaic cells using solution-processed Copper (I) Iodide (CuI) as hole transport layer (HTL). Our devices exhibit a PCE value of ∼5.5% which is equivalent to that obtained for control devices based on the commonly used conductive polymer poly(3,4-ethylenedioxythiophene): polystyrenesulfonate as HTL. Inverted cells with PCE >3% were also demonstrated using solution-processed metal oxide electron transport layers, with a CuI HTL evaporated on top of the BHJ. The high optical transparency and suitable energetics of CuI make it attractive for application in a range of inexpensive large-area optoelectronic devices

Spatial Pattern of Copper Phosphate Precipitation Involves in Copper Accumulation and Resistance of Unsaturated Pseudomonas putida CZ1 Biofilm.

Science.gov (United States)

Chen, Guangcun; Lin, Huirong; Chen, Xincai

2016-12-28

Bacterial biofilms are spatially structured communities that contain bacterial cells with a wide range of physiological states. The spatial distribution and speciation of copper in unsaturated Pseudomonas putida CZ1 biofilms that accumulated 147.0 mg copper per g dry weight were determined by transmission electron microscopy coupled with energy dispersive X-ray analysis, and micro-X-ray fluorescence microscopy coupled with micro-X-ray absorption near edge structure (micro-XANES) analysis. It was found that copper was mainly precipitated in a 75 μm thick layer as copper phosphate in the middle of the biofilm, while there were two living cell layers in the air-biofilm and biofilm-medium interfaces, respectively, distinguished from the copper precipitation layer by two interfaces. The X-ray absorption fine structure analysis of biofilm revealed that species resembling Cu₃(PO₄)₂ predominated in biofilm, followed by Cu-Citrate- and Cu-Glutathione-like species. Further analysis by micro-XANES revealed that 94.4% of copper were Cu₃(PO₄)₂-like species in the layer next to the air interface, whereas the copper species of the layer next to the medium interface were composed by 75.4% Cu₃(PO₄)₂, 10.9% Cu-Citrate-like species, and 11.2% Cu-Glutathione-like species. Thereby, it was suggested that copper was initially acquired by cells in the biofilm-air interface as a citrate complex, and then transported out and bound by out membranes of cells, released from the copper-bound membranes, and finally precipitated with phosphate in the extracellular matrix of the biofilm. These results revealed a clear spatial pattern of copper precipitation in unsaturated biofilm, which was responsible for the high copper tolerance and accumulation of the biofilm.

Application of high-pressure techniques: stabilization and oxidation-state control of novel superconductive and related multi-layered copper oxides

International Nuclear Information System (INIS)

Yamauchi, H.; Karppinen, M.

2000-01-01

Copper oxide superconductors possess multi-layered structures with a layer sequence of -CuO 2 -(Q-CuO 2 ) n-1 -AO-(MO 1±δ ) m -AO- or -CuO 2 -B-(O 2 -B) s-1 -CuO 2 -AO-(MO 1±δ ) m -AO- along the elongated c axis. Based on this layer sequence, the known copper oxide structures are categorized as members of the homologous series, M m A r Q n-1 Cu n O m+r+2 +n ±δ (M-mr(n-1)n ; category A) or M m A 2k B s Cu 1+k O m +4k +2s±δ (M-m(2k)s (1+k ); category B). Stabilization of such structures especially in the case of high values of the n /s parameter, i.e. the higher members of the homologous series, has been demonstrated to be apparently promoted under high pressures and/or strongly oxidizing conditions. Consequently, techniques for applying both high oxygen gas pressures (10-2000 atm) and ultra-high solid-medium pressures (2-8 GPa) have been advantageously utilized in synthesizing various superconductive copper oxide phases. Especially the ultra-high solid-medium pressure synthesis carried out in the so-called cubic-anvil/belt-type apparatus has proven to be extremely successful in synthesizing novel superconductive phases. In order to achieve high partial pressures of oxygen in the solid-medium environment, 'external' oxygen-generating oxides such as KClO 4 , KClO 3 and Ag 2 O 2 are commonly added to the precursor mixtures. It is emphasized that in some cases it is possible to utilize 'internal' oxidizing agents alone, i.e. highly oxidized precursors such as BaCuO 2+δ and Ba 2 Cu 3 O 5+δ containing metal constituents common with the desired copper oxide phase only. In the present paper, the potential and applications of high-pressure techniques in synthesizing multi-layered copper oxides and related structures are reviewed and discussed with emphasis on the important 'historical' discoveries of novel phases and the present status of controlled production of high-quality samples of such phases. (author)

An investigation into the effect of equal channel angular extrusion process on mechanical and microstructural properties of middle layer in copper clad aluminum composite

International Nuclear Information System (INIS)

Tolaminejad, B.; Karimi Taheri, A.; Arabi, H.; Shahmiri, M.

2009-01-01

Equal channel angular extrusion is a promising technique for production of ultra fine-grain materials of few hundred nanometers size. In this research, the grain refinement of aluminium strip is accelerated by sandwiching it between two copper strips and then subjecting the three strips to Equal channel angular extrusion process simultaneously. The loosely packed copper-aluminium-copper laminated billet was passed through Equal channel angular extrusion die up to 8 passes using the Bc route. Then, tensile properties and some microstructural characteristics of the aluminium layer were evaluated. The scanning and transmission electron microscopes, and X-ray diffraction were used to characterize the microstructure. The results show that the yield stress of middle layer (Al) is increased significantly by about four times after application of Equal channel angular extrusion throughout the four consecutive passes and then it is slightly decreased when more Equal channel angular extrusion passes are applied. An ultra fine grain within the range of 500 to 600 nm was obtained in the Al layer by increasing the thickness of the copper layers. lt was observed that the reduction of grain size in the aluminium layer is nearly 55% more than that of a equal channel angular-extruded single layer aluminium billet, i.e. extruding a single aluminium strip or a billet without any clad for the same amount of deformation. This behaviour was attributed to the higher rates of dislocations interaction and cell formation and texture development during the Equal channel angular extrusion of the laminated composite compared to those of a single billet.

Colloidal and electrochemical aspects of copper-CMP

Science.gov (United States)

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 (electrocoagulation was investigated to remove both copper and abrasive slurry particles simultaneously. For effluent containing ˜40 ppm dissolved copper, it was found that ˜90% dissolved copper was removed from the waste streams through electroplating and in-situ chemical precipitation. The amount of copper removed through plating is impacted by membrane surface charge, type/amount of complexing agents, and solid content in the slurry suspension. The slurry particles can be removed ˜90% within 2 hours of EC through multiple mechanisms.

Enhancement of absorption in vertically-oriented graphene sheets growing on a thin copper layer

Energy Technology Data Exchange (ETDEWEB)

Rozouvan, Tamara; Poperenko, Leonid [Taras Shevchenko National University of Kyiv, Department of Physics 4, Prospect Glushkova, Kyiv, 03187 (Ukraine); Kravets, Vasyl, E-mail: vasyl_kravets@yahoo.com [School of Physics and Astronomy, University of Manchester, Manchester, M13 9PL (United Kingdom); Shaykevich, Igor [Taras Shevchenko National University of Kyiv, Department of Physics 4, Prospect Glushkova, Kyiv, 03187 (Ukraine)

2017-02-28

Highlights: • The optical properties and surface structure of graphene films. • Chemical vapour deposition method. • Scanning tunneling microscopy revealed vertical crystal lattice structure of graphene layer. • We report a significant enhancement of the absorption band in the vertically-oriented graphene sheets. - Abstract: The optical properties and surface structure of graphene films grown on thin copper Cu (1 μm) layer using chemical vapour deposition method were investigated via spectroscopic ellipsometry and nanoscopic measurements. Angle variable ellipsometry measurements were performed to analyze the features of dispersion of the complex refractive index and optical conductivity. It was observed significant enhancement of the absorption band in the vertically-oriented graphene sheets layer with respect to the bulk graphite due to interaction between excited localized surface plasmon at surface of thin Cu layer and graphene’s electrons. Scanning tunneling microscopy measurements with atomic spatial resolution revealed vertical crystal lattice structure of the deposited graphene layer. The obtained results provide direct evidence of the strong influence of the growing condition and morphology of nanostructure on electronic and optical behaviours of graphene film.

Tribological properties of copper-based composites with copper coated NbSe2 and CNT

International Nuclear Information System (INIS)

Chen, Beibei; Yang, Jin; Zhang, Qing; Huang, Hong; Li, Hongping; Tang, Hua; Li, Changsheng

2015-01-01

Graphical abstract: Morphology of copper coated NbSe 2 and CNT; friction coefficient and wear rate of copper-based composites. - Highlights: • NbSe 2 and CNT were coated with copper layers by the means of electroless plating. • The mechanical and tribological properties of copper composites were studied. • The enhancement mechanisms of copper coated NbSe 2 and CNT were proposed. • Copper–copper coated (12 wt.%NbSe 2 –3 wt.%CNT) composite had the best wear resistance. - Abstract: Copper-based composites with copper coated NbSe 2 and/or CNT were fabricated by the powder metallurgy technique. The morphology and phase composition of copper coated NbSe 2 and carbon nanotube (CNT) were observed using high solution transmission electronic microscope (HRTEM), scanning electronic microscope (SEM equipped with EDS) and X-ray diffraction (XRD). The density, hardness, and bending strength of as-prepared copper-based composites were measured, and their tribological properties were investigated using UMT-2 tester. Results indicated that all copper-based composites showed decreased density and bending strength, but increased hardness in comparison with copper matrix. Besides, the incorporation of copper coated NbSe 2 improved the friction-reducing and anti-wear properties of copper matrix. Addition of copper coated CNT greatly enhanced the mechanical and tribological properties. In particular, when the content of copper coated CNT was 3 wt.%, the corresponding composite exhibited the best tribological properties. This was because NbSe 2 was distributed chaotically in matrix, which greatly improved the friction-reducing property of copper, while CNT with superior mechanical strength enhanced the wear resistance by increasing the load-carrying capacity. More importantly, copper layers coated on NbSe 2 and CNT favored the good interfacial combination between fillers and copper matrix showing beneficial effect for the stresses transferring from matrix to fillers

In vitro effects of copper nanoparticles on plant pathogens, beneficial microbes and crop plants

Energy Technology Data Exchange (ETDEWEB)

Banik, S.; Pérez-de-Luque, A.

2017-07-01

Copper-based chemicals are effectively used as antimicrobials in agriculture. However, with respect to its nanoparticulate form there has been limited number of studies. In this investigation, in vitro tests on effect of copper nanoparticles (CuNPs) against plant pathogenic fungi, oomycete, bacteria, beneficial microbes Trichoderma harzianum and Rhizobium spp., and wheat seeds were conducted. Integration of CuNPs with non-nano copper like copper oxychloride (CoC) at 50 mg/L concentration each recorded 76% growth inhibition of the oomycete Phytophthora cinnamomi in vitro compared to the control. CuNPs also showed synergistic inhibitory effect with CoC on mycelial growth and sporulation of A. alternata. Pseudomonas syringae was inhibited at 200 mg/L of CuNPs. CuNPs were not significantly biocidal against Rhizobium spp. and Trichoderma harzianum compared to CoC. Evaluation of the effect of CuNP on wheat revealed that rate of germination of wheat seeds was higher in presence of CuNPs and CoC compared to control. Germination vigor index, root length, shoot dry weight and seed metabolic efficiency of wheat were negatively affected. At low concentration, CuNPs promoted the growth of the plant pathogenic fungi Botrytis fabae, Fusarium oxysporum f.sp. ciceris, F.oxysporum f.sp. melonis, Alternaria alternate and P. syringae, and sporulation of T. harzianum. Synergistic effect of CuNPs and CoC in inhibiting P. cinnamomi offers a possibility of developing new fungicide formulation for better control of the oomycetes. Non-biocidal effect of CuNPs against beneficial microbes indicates its potential use in the agri-ecosystem.

In vitro effects of copper nanoparticles on plant pathogens, beneficial microbes and crop plants

International Nuclear Information System (INIS)

Banik, S.; Pérez-de-Luque, A.

2017-01-01

Copper-based chemicals are effectively used as antimicrobials in agriculture. However, with respect to its nanoparticulate form there has been limited number of studies. In this investigation, in vitro tests on effect of copper nanoparticles (CuNPs) against plant pathogenic fungi, oomycete, bacteria, beneficial microbes Trichoderma harzianum and Rhizobium spp., and wheat seeds were conducted. Integration of CuNPs with non-nano copper like copper oxychloride (CoC) at 50 mg/L concentration each recorded 76% growth inhibition of the oomycete Phytophthora cinnamomi in vitro compared to the control. CuNPs also showed synergistic inhibitory effect with CoC on mycelial growth and sporulation of A. alternata. Pseudomonas syringae was inhibited at 200 mg/L of CuNPs. CuNPs were not significantly biocidal against Rhizobium spp. and Trichoderma harzianum compared to CoC. Evaluation of the effect of CuNP on wheat revealed that rate of germination of wheat seeds was higher in presence of CuNPs and CoC compared to control. Germination vigor index, root length, shoot dry weight and seed metabolic efficiency of wheat were negatively affected. At low concentration, CuNPs promoted the growth of the plant pathogenic fungi Botrytis fabae, Fusarium oxysporum f.sp. ciceris, F.oxysporum f.sp. melonis, Alternaria alternate and P. syringae, and sporulation of T. harzianum. Synergistic effect of CuNPs and CoC in inhibiting P. cinnamomi offers a possibility of developing new fungicide formulation for better control of the oomycetes. Non-biocidal effect of CuNPs against beneficial microbes indicates its potential use in the agri-ecosystem.

Synthesis and characterization of copper, polyimide and TIPS-pentacene layers for the development of a solution processed fibrous transistor

Directory of Open Access Journals (Sweden)

B. Van Genabet

2011-12-01

Full Text Available A study was performed for the development of a flexible organic field effect transistor starting from a polyester fibre as substrate material. Focus of subsequent layer deposition was on low temperature soluble processes to allow upscaling. Gate layer consists out of a pyrrole polymerization and copper coating step. Polyimide dielectric layer was deposited using dipcoating. Gold electrodes were vacuum evaporated and patterned via mask fibre shadowing. The active layer consisted of a soluble p-type TIPS-pentacene organic semiconductor. Different deposition techniques have been examined. Considerable progress in development of a transistor has been made.

Morphological features of the copper surface layer under sliding with high density electric current

Energy Technology Data Exchange (ETDEWEB)

Fadin, V. V., E-mail: fvv@ispms.ru [Institute of Strength Physics and Materials Science SB RAS, Tomsk, 634055 (Russian Federation); Aleutdinova, M. I., E-mail: aleut@ispms.ru [Institute of Strength Physics and Materials Science SB RAS, Tomsk, 634055 (Russian Federation); Seversk Technological Institute, Branch of State Autonomous Educational Institution of Higher Professional Education “National Research Nuclear University “MEPhI”, Seversk, 636036 (Russian Federation); Rubtsov, V. Ye., E-mail: rvy@ispms.ru [Institute of Strength Physics and Materials Science SB RAS, Tomsk, 634055 (Russian Federation); National Research Tomsk Polytechnic University, Tomsk, 634050 (Russian Federation); Aleutdinova, V. A., E-mail: valery-aleut@yandex.ru [National Research St. Petersburg State Polytechnical University, St. Petersburg, 195251 (Russian Federation)

2015-10-27

Conductivity and wear intensity of copper under the influence of dry friction and electric current with contact density higher 100 A/cm{sup 2} are presented. It is shown that an increase in hardness and heat outflow from a friction zone leads to the reduction of wear intensity and current contact density increase corresponding to the beginning of catastrophic wear. Structural changes, such as the formation of FeO oxide and α-Fe particles in the copper surface layer, have also been found. It is observed that a worn surface is deformed according to a viscous liquid mechanism. Such singularity is explained in terms of appearance of high-excited atomic states in deforming micro-volumes near contact spots that lead to easy stress relaxation by local plastic shears in the vicinity of stress concentrators. In common this effect allows to achieve high wear resistance.

A study on the optics of copper indium gallium (di)selenide (CIGS) solar cells with ultra-thin absorber layers.

Science.gov (United States)

Xu, Man; Wachters, Arthur J H; van Deelen, Joop; Mourad, Maurice C D; Buskens, Pascal J P

2014-03-10

We present a systematic study of the effect of variation of the zinc oxide (ZnO) and copper indium gallium (di)selenide (CIGS) layer thickness on the absorption characteristics of CIGS solar cells using a simulation program based on finite element method (FEM). We show that the absorption in the CIGS layer does not decrease monotonically with its layer thickness due to interference effects. Ergo, high precision is required in the CIGS production process, especially when using ultra-thin absorber layers, to accurately realize the required thickness of the ZnO, cadmium sulfide (CdS) and CIGS layer. We show that patterning the ZnO window layer can strongly suppress these interference effects allowing a higher tolerance in the production process.

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

DEFF Research Database (Denmark)

Elguindi, J; Moffitt, S; Hasman, Henrik

2010-01-01

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...... 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....

Underwater explosive compaction-sintering of tungsten-copper coating on a copper surface

Science.gov (United States)

Chen, Xiang; Li, Xiaojie; Yan, Honghao; Wang, Xiaohong; Chen, Saiwei

2018-01-01

This study investigated underwater explosive compaction-sintering for coating a high-density tungsten-copper composite on a copper surface. First, 50% W-50% Cu tungsten-copper composite powder was prepared by mechanical alloying. The composite powder was pre-compacted and sintered by hydrogen. Underwater explosive compaction was carried out. Finally, a high-density tungsten-copper coating was obtained by diffusion sintering of the specimen after explosive compaction. A simulation of the underwater explosive compaction process showed that the peak value of the pressure in the coating was between 3.0 and 4.8 GPa. The hardness values of the tungsten-copper layer and the copper substrate were in the range of 87-133 and 49 HV, respectively. The bonding strength between the coating and the substrate was approximately 100-105 MPa.

Surface films and corrosion of copper

International Nuclear Information System (INIS)

Hilden, J.; Laitinen, T.; Maekelae, K.; Saario, T.; Bojinov, M.

1999-03-01

In Sweden and Finland the spent nuclear fuel is planned to be encapsulated in cast iron canisters that have an outer shield made of copper. The copper shield is responsible for the corrosion protection of the canister construction. General corrosion of the copper is not expected to be the limiting factor in the waste repository environment when estimating the life-time of the canister construction. However, different forms of localised corrosion, i.e. pitting, stress corrosion cracking, or environmentally assisted creep fracture may cause premature failure of the copper shield. Of the probable constituents in the groundwater, nitrites, chlorides, sulphides and carbonates have been suggested to promote localised corrosion of copper. The main assumption made in planning this research program is that the surface films forming on copper in the repository environment largely determine the susceptibility of copper to the different forms of localised corrosion. The availability of reactants, which also may become corrosion rate limiting, is investigated in several other research programs. This research program consists of a set of successive projects targeted at characterising the properties of surface films on copper in repository environment containing different detrimental anions. A further aim was to assess the significance of the anion-induced changes in the stability of the oxide films with regard to localised corrosion of copper. This report summarises the results from a series of investigations on properties of surface films forming on copper in water of pH = 8.9 at temperature of 80 deg C and pressure of 2 MPa. The main results gained so far in this research program are as follows: The surface films forming on copper in the thermodynamic stability region of monovalent copper at 80 deg C consist of a bulk part (about 1 mm thick) which is a good ionic and electronic conductor, and an outer, interfacial layer (0.001 - 0.005 mm thick) which shows p-type semiconductor

Post-ion beam induced degradation of copper layers in transmission electron microscopy specimens

Science.gov (United States)

Seidel, F.; Richard, O.; Bender, H.; Vandervorst, W.

2015-11-01

Copper containing transmission electron microscopy (TEM) specimens frequently show corrosion after focused ion beam (FIB) preparation. This paper reveals that the corrosion product is a Cu-S phase growing over the specimen surface. The layer is identified by energy-dispersive x-ray spectroscopy, and lattice spacing indexing of power spectra patterns. The corrosion process is further studied by TEM on cone-shaped specimens, which are intentionally stored after FIB preparation with S flakes for short time. Furthermore, a protective method against corrosion is developed by varying the time in the FIB vacuum and the duration of a subsequent plasma cleaning.

In vitro response of phaeoramularia angolensis to commonly used fungicides in Kenya

International Nuclear Information System (INIS)

Juma, I.M.; Siboe, M.

1996-01-01

The leaf and fruit spot disease of citrus spp. caused by the fungus Phaeoramularia angolensis Kirk is new and epidemic in Kenya, with a 100% crop yield loss. Poor response to fungicide application led to the suspicion that the fungus was resistant to conventional fungicides, hence the difficulties experienced in its control. Therefore the study was carried out to establish wether P.angolensis isolates from Western Kenya were screened for resistance. The following fungicides were used: copper fungicides(Cupric hydroxide 50% WP or kocide 101 and copper oxychloride 50% WP), Mancozeb 70% WP (Dithane M45)and Propineb 80% WPC (Antracol). Mancozeb 70% WP and Propineb were the most effective with LD-5-0 at 0.03 ppm and 0.25 ppm respectively. Copper fungicide LD-5-0 was above 3000 ppm (current manufacturers' recommended dosage is 7,500 ppm and 6,900 ppm for kocide 101 and copper oxychloride respectively). There was no obvious evidence of resistance. The fungi- static characteristics of copper fungicides and the application of wrong dosage and timing could be the reason for the difficulties experienced in the control of the disease. (author) 14 refs., 2 tables, 1 graph

Atmospheric corrosion effects on copper

International Nuclear Information System (INIS)

Franey, J.P.

1985-01-01

Studies have been performed on the naturally formed patina on various copper samples. Samples have been obtained from structures at AT and T Bell Laboratories, Murray Hill, NJ (40,2,1 and <1 yr) and the Statue of Liberty (100 yr). The samples show a distinct layering effect, that is, the copper base material shows separate oxide and basic sulfate layers on all samples, indicating that patina is not a homogeneous mixture of oxides and basic sulfates

Layer-by-Layer Nanoassembly of Copper Indium Gallium Selenium Nanoparticle Films for Solar Cell Applications

Directory of Open Access Journals (Sweden)

A. Hemati

2012-01-01

Full Text Available Thin films of CIGS nanoparticles interdigited with polymers have been fabricated through a cost-effective nonvacuum film deposition process called layer-by-layer (LbL nanoassembly. CIGS nanoparticles synthesized by heating copper chloride, indium chloride, gallium chloride, and selenium in oleylamine were dispersed in water, and desired surface charges were obtained through pH regulation and by coating the particles with polystyrene sulfonate (PSS. Raising the pH of the nanoparticle dispersion reduced the zeta-potential from +61 mV at pH 7 to −51 mV at pH 10.5. Coating the CIGS nanoparticles with PSS (CIGS-PSS produced a stable dispersion in water with −56.9 mV zeta-potential. Thin films of oppositely charged CIGS nanoparticles (CIGS/CIGS, CIGS nanoparticles and PSS (CIGS/PSS, and PSS-coated CIGS nanoparticles and polyethylenimine (CIGS-PSS/PEI were constructed through the LbL nanoassembly. Film thickness and resistivity of each bilayer of the films were measured, and photoelectric properties of the films were studied for solar cell applications. Solar cell devices fabricated with a 219 nm CIGS film, when illuminated by 50 W light-source, produced 0.7 V open circuit voltage and 0.3 mA/cm2 short circuit current density.

Development of Copper Canister through Cold Sprayed Coating Method

Energy Technology Data Exchange (ETDEWEB)

Lee, Min Soo; Choi, Jong Won; Choi, Heui Joo; Lee, Jong Youl; Jeong, Jong Tae; Kim, Sung Ki; Cho, Dong Keun

2007-12-15

General thickness of a copper canister is 5 cm for a underground disposal application. The lower limit of a thickness is determined by a forging technology. But many experts in this area agrees that the thickness 1 cm is enough at the underground disposal for the life time of 1,000,000 years. Thus new technology is suggested for the making 1 cm thickness copper canister, that is a cold spray coating method(CSC). In this report, the CSC is examined and the technical possibility for making copper canister is measured. The overview of CSC and its characteristics are discussed. Various copper particles for the CSC are analyzed and the formed coating layers are examined to find their porosity and uniformity. A Tafa copper particle and Chang-sung copper particle are selected for making 1 cm thick test specimen. Using the CSC specimens, tensile test and XRD analysis are performed. As a corrosion evaluation, a electrochemical test such as a polarization test is done, together with humid corrosion test and chloric acid immersion test. Through the corrosion tests, it is tried to confirm that the CSC is valuable method for making a copper canister. Consequently, it is confirmed that the CSC method is very usful for making 1 cm thick copper canister. the porosity of CSC layer is very low at 0.3 in case of Tafa copper layer. In corrosion tests, the CSC layers are very stable in active environments. It is hard to say that the difference of processing method but the purity of copper is important for the corrosion rate evaluation. The CSC method is very effective method for making 1 cm thick copper canister, It is hoped that the CSC method is applied in a HLW underground disposal system in the future.

Development of Copper Canister through Cold Sprayed Coating Method

International Nuclear Information System (INIS)

Lee, Min Soo; Choi, Jong Won; Choi, Heui Joo; Lee, Jong Youl; Jeong, Jong Tae; Kim, Sung Ki; Cho, Dong Keun

2007-12-01

General thickness of a copper canister is 5 cm for a underground disposal application. The lower limit of a thickness is determined by a forging technology. But many experts in this area agrees that the thickness 1 cm is enough at the underground disposal for the life time of 1,000,000 years. Thus new technology is suggested for the making 1 cm thickness copper canister, that is a cold spray coating method(CSC). In this report, the CSC is examined and the technical possibility for making copper canister is measured. The overview of CSC and its characteristics are discussed. Various copper particles for the CSC are analyzed and the formed coating layers are examined to find their porosity and uniformity. A Tafa copper particle and Chang-sung copper particle are selected for making 1 cm thick test specimen. Using the CSC specimens, tensile test and XRD analysis are performed. As a corrosion evaluation, a electrochemical test such as a polarization test is done, together with humid corrosion test and chloric acid immersion test. Through the corrosion tests, it is tried to confirm that the CSC is valuable method for making a copper canister. Consequently, it is confirmed that the CSC method is very usful for making 1 cm thick copper canister. the porosity of CSC layer is very low at 0.3 in case of Tafa copper layer. In corrosion tests, the CSC layers are very stable in active environments. It is hard to say that the difference of processing method but the purity of copper is important for the corrosion rate evaluation. The CSC method is very effective method for making 1 cm thick copper canister, It is hoped that the CSC method is applied in a HLW underground disposal system in the future

Electro-oxidation nitrite based on copper calcined layered double hydroxide and gold nanoparticles modified glassy carbon electrode

Energy Technology Data Exchange (ETDEWEB)

Cui Lin; Meng Xiaomeng; Xu Minrong; Shang Kun [College of Chemistry and Material Science, Shandong Agricultural University, Taian 271018, Shandong (China); Ai Shiyun, E-mail: ashy@sdau.edu.cn [College of Chemistry and Material Science, Shandong Agricultural University, Taian 271018, Shandong (China); Liu Yinping [College of Chemistry and Material Science, Shandong Agricultural University, Taian 271018, Shandong (China)

2011-11-30

Highlights: > A nitrite sensor fabricated based on copper calcined layered double hydroxides and gold nanoparticles modified electrode. > This sensor exhibited excellent electrocatalytic oxidation to nitrite. > This nitrite sensor exhibited very good analytical performance with low cost, convenient preparation and rapid detection. - Abstract: In this paper, a novel nitrite sensor was constructed based on electrodeposition of gold nanoparticles (AuNPs) on a copper calcined layered double hydroxide (Cu-CLDH) modified glassy carbon electrode. Electrochemical experiments showed that AuNPs/CLDH composite film exhibited excellent electrocatalytic oxidation activity with nitrite due to the synergistic effect of the Cu-CLDH with AuNPs. The fabricated sensor exhibited excellent performance for nitrite detection within a wide concentration interval of 1-191 {mu}M and with a detection limit of 0.5 {mu}M. The superior electrocatalytic response to nitrite was mainly attributed to the large surface area, minimized diffusion resistance, and enhanced electron transfer of the Cu-CLDH and AuNPs composition film. This platform offers a novel route for nitrite sensing with wide analytical applications and will supply the practical applications for a variety of simple, robust, and easy-to-manufacture analytical approaches in the future.

Electro-oxidation nitrite based on copper calcined layered double hydroxide and gold nanoparticles modified glassy carbon electrode

International Nuclear Information System (INIS)

Cui Lin; Meng Xiaomeng; Xu Minrong; Shang Kun; Ai Shiyun; Liu Yinping

2011-01-01

Highlights: → A nitrite sensor fabricated based on copper calcined layered double hydroxides and gold nanoparticles modified electrode. → This sensor exhibited excellent electrocatalytic oxidation to nitrite. → This nitrite sensor exhibited very good analytical performance with low cost, convenient preparation and rapid detection. - Abstract: In this paper, a novel nitrite sensor was constructed based on electrodeposition of gold nanoparticles (AuNPs) on a copper calcined layered double hydroxide (Cu-CLDH) modified glassy carbon electrode. Electrochemical experiments showed that AuNPs/CLDH composite film exhibited excellent electrocatalytic oxidation activity with nitrite due to the synergistic effect of the Cu-CLDH with AuNPs. The fabricated sensor exhibited excellent performance for nitrite detection within a wide concentration interval of 1-191 μM and with a detection limit of 0.5 μM. The superior electrocatalytic response to nitrite was mainly attributed to the large surface area, minimized diffusion resistance, and enhanced electron transfer of the Cu-CLDH and AuNPs composition film. This platform offers a novel route for nitrite sensing with wide analytical applications and will supply the practical applications for a variety of simple, robust, and easy-to-manufacture analytical approaches in the future.

Aluminium or copper substrate panel for selective absorption of solar energy

Science.gov (United States)

Roberts, M. L.; Sharpe, M. H.; Krupnick, A. C. (Inventor)

1979-01-01

A method for making panels which selectively absorb solar energy is disclosed. The panels are comprised of an aluminum substrate, a layer of zinc thereon, a layer of nickel over the zinc layer and an outer layer of solar energy absorbing nickel oxide or a copper substrate with a layer of nickel thereon and a layer of solar energy absorbing nickel oxide distal from the copper substrate.

Magnetic characterization of the nickel layer protecting the copper wires in harsh applications

Directory of Open Access Journals (Sweden)

Roger Daniel

2017-06-01

Full Text Available High Temperature (HT° motor coils open new perspectives for extending the applications of electrical motors or generators to very harsh environments or for designing very high power density machines working with high internal temperature gradients. Over a temperature of 300°C, the classic enameled wire cannot work permanently, the turn-to-turn insulation must be inorganic and made with high temperature textiles or vitro-ceramic compounds. For both cases, a diffusion barrier must protect the copper wire against oxidation. The usual solution consists of adding a nickel layer that yields an excellent chemical protection. Unfortunately, the nickel has ferromagnetic properties that change a lot the skin effect in the HT wire at high frequencies. For many applications such as aeronautics, electrical machines are always associated with PWM inverters for their control. The windings must resist to high voltage short spikes caused by the fast fronted pulses imposed by the feeding inverter. The nickel protection layer of the HT° inorganic wire has a large influence on the high frequency behavior of coils and, consequently, on the magnitude of the voltage spikes. A good knowledge of the non-linear magnetic characteristics of this nickel layer is helpful for designing reliable HT inorganic coils. The paper presents a method able to characterize non-linear electromagnetic properties of this nickel layer up to 500°C.

Controlling the Performance of P-type Cu2O/SnO Bilayer Thin-Film Transistors by Adjusting the Thickness of the Copper Oxide Layer

KAUST Repository

Al-Jawhari, Hala A.; Caraveo-Frescas, Jesus Alfonso; Hedhili, Mohamed N.

2014-01-01

The effect of copper oxide layer thickness on the performance of Cu2O/SnO bilayer thin-film transistors was investigated. By using sputtered Cu2O films produced at an oxygen partial pressure, Opp, of 10% as the upper layer and 3% Opp SnO films

A study on the optics of copper indium gallium (di)selenide (CIGS) solar cells with ultra-thin absorber layers

NARCIS (Netherlands)

Xu, M.; Wachters, A.J.H.; Van Deelen, J.; Mourad, M.C.D.; Buskens, P.J.P.

2014-01-01

We present a systematic study of the effect of variation of the zinc oxide (ZnO) and copper indium gallium (di)selenide (CIGS) layer thickness on the absorption characteristics of CIGS solar cells using a simulation program based on finite element method (FEM). We show that the absorption in the

Interfacial Microstructure and Its Influence on Resistivity of Thin Layers Copper Cladding Steel Wires

Science.gov (United States)

Li, Hongjuan; Ding, Zhimin; Zhao, Ruirong

2018-04-01

The interfacial microstructure and resistivity of cold-drawn and annealed thin layers copper cladding steel (CCS) wires have been systematically investigated by the methods of scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and resistivity testing. The results showed that the Cu and Fe atoms near interface diffused into each other matrixes. The Fe atoms diffused into Cu matrixes and formed a solid solution. The mechanism of solid solution is of substitution type. When the quantity of Fe atoms exceeds the maximum solubility, the supersaturated solid solution would form Fe clusters and decompose into base Cu and α-Fe precipitated phases under certain conditions. A few of α-Fe precipitates was observed in the copper near Cu/Fe interfaces of cold-drawn CCS wires, with 1-5 nm in size. A number of α-Fe precipitates of 1-20 nm in size can be detected in copper near Cu/Fe interfaces of CCS wires annealed at 850°C. When annealing temperature was less than 750°C, the resistivity of CCS wires annealed was lower than that of cold-drawn CCS wires. However, when annealing temperature was above 750°C, the resistivity of CCS wires was greater than that of cold-drawn CCS wires and increased with rising the annealing temperature. The relationship between nanoscale α-Fe precipitation and resistivity of CCS wires has been well discussed.

Thermally driven self-healing using copper nanofiber heater

Science.gov (United States)

Lee, Min Wook; Jo, Hong Seok; Yoon, Sam S.; Yarin, Alexander L.

2017-07-01

Nano-textured transparent heaters made of copper nanofibers (CuNFs) are used to facilitate accelerated self-healing of bromobutyl rubber (BIIR). The heater and BIIR layer are separately deposited on each side of a transparent flexible polyethylene terephthalate (PET) substrate. A pre-notched crack on the BIIR layer was bridged due to heating facilitated by CuNFs. In the corrosion test, a cracked BIIR layer covered a steel substrate. An accelerated self-healing of the crack due to the transparent copper nanofiber heater facilitated an anti-corrosion protective effect of the BIIR layer.

Chemical bath deposited zinc sulfide buffer layers for copper indium gallium sulfur-selenide solar cells and device analysis

International Nuclear Information System (INIS)

Kundu, Sambhu; Olsen, Larry C.

2005-01-01

Cadmium-free copper indium gallium sulfur-selenide (CIGSS) thin film solar cells have been fabricated using chemical bath deposited (CBD) zinc sulfide (ZnS) buffer layers. Shell Solar Industries provided high quality CIGSS absorber layers. The use of CBD-ZnS, which is a higher band gap material than CdS, improved the quantum efficiency of fabricated cells at lower wavelengths, leading to an increase in short circuit current. The best cell to date yielded an active area (0.43 cm 2 ) efficiency of 13.3%. The effect of the ZnS buffer layer thickness on device performance was studied carefully. This paper also presents a discussion of issues relevant to the use of the CBD-ZnS buffer material for improving device performance

In vitro colonial inhibition of an isolate from Colletotrichum acutatum Simmonds to fungicide treatments

Directory of Open Access Journals (Sweden)

Dagoberto Guillén Sánchez

2018-02-01

Full Text Available The aim of the research was to evaluate the in vitro sensitivity of Colletotrichum acutatum antracnosis to seven fungicides. It began with an isolate preserved in the ceparium of the Phytopathology Laboratory of the High School Studies of Xalostoc, Morelos. A completely randomized design was used to evaluate the fungicides benomyl, diphenoconazole, azoxystrobin, trifloxystrobin, copper oxychloride, fluoxastrobin and captan, at high, medium and low doses, for a total of 22 treatments with six repetitions. Sterile distilled water was applied to the control. The treatments were applied at a rate of 5 mL per plate, which contained PDA medium and a mycelial disc (Ø 5 mm. The inoculated plates were incubated at 24 °C, in 12 hour photoperiod. The colony diameter was measured every 24 hours and the percent inhibition was calculated. A bifactorial variance analysis was performed, according to Fungicide and Dose; and the differences between treatments were detected by the LSD test with 95 % confidence. The diameter of the colony and the percentage of inhibition did not show differences for dose levels, without significant effects for the interaction of both factors, fungicides, and dose. However, all doses of the different fungicides inhibited colony growth compared to the control. The benomyl, difenoconazol and captan fungicides were able to totally reduce the growth of the C. acutatum colony; followed by copper oxychloride, azoxystrobin, fluoxastrobin and trifloxystrobin in decreasing order. Only benomyl, difenoconazol, captan and copper oxychloride achieved more than 50 % inhibition.

Multilayer graphene as an effective corrosion protection coating for copper

Science.gov (United States)

Ravishankar, Vasumathy; Ramaprabhu, S.; Jaiswal, Manu

2018-04-01

Graphene grown by chemical vapor deposition (CVD) has been studied as a protective layer against corrosion of copper. The layer number dependence on the protective nature of graphene has been investigated using techniques such as Tafel analysis and Electroimpedance Spectroscopy. Multiple layers of graphene were achieved by wet transfer above CVD grown graphene. Though this might cause grain boundaries, the sites where corrosion is initiated, to be staggered, wet transfer inherently carries the disadvantage of tearing of graphene, as confirmed by Raman spectroscopy measurements. However, Electroimpedance Spectroscopy (EIS) reflects that graphene protected copper has a layer dependent resistance to corrosion. Decrease in corrosion current (Icorr) for graphene protected copper is presented. There is only small dependence of corrosion current on the layer number, Tafel plots clearly indicate passivation in the presence of graphene, whether it be single layer or multiple layers. Notwithstanding the crystallite size, defect free layers of graphene with staggered grain boundaries combined with passivation could offer good corrosion protection for metals.

Bifunctional sensor of pentachlorophenol and copper ions based on nanostructured hybrid films of humic acid and exfoliated layered double hydroxide via a facile layer-by-layer assembly

International Nuclear Information System (INIS)

Yuan, Shuang; Peng, Dinghua; Hu, Xianluo; Gong, Jingming

2013-01-01

Graphical abstract: -- Highlights: •A new highly sensitive bifunctional electrochemical sensor developed. •As-prepared sensor fabricated by alternate assembly of HA and exfoliated LDH nanosheets. •Such a newly designed sensor combining the individual properties of HA and LDH nanosheets. •Simultaneous determination of pentachlorophenol and copper ions achieved. •Practical applications demonstrated in water samples. -- Abstract: A new, highly sensitive bifunctional electrochemical sensor for the simultaneous determination of pentachlorophenol (PCP) and copper ions (Cu 2+ ) has been developed, where organic–inorganic hybrid ultrathin films were fabricated by alternate assembly of humic acid (HA) and exfoliated Mg–Al-layered double hydroxide (LDH) nanosheets onto ITO substrates via a layer-by-layer (LBL) approach. The multilayer films were then characterized by means of UV–vis spectrometry, scanning electron microscopy (SEM), and atomic force microscope (AFM). These films were found to have a relatively smooth surface with almost equal amounts of HA incorporated in each cycle. Its electrochemical performance was systematically investigated. Our results demonstrate that such a newly designed (LDH/HA) n multilayer films, combining the individual properties of HA (dual recognition ability for organic herbicides and metal ions) together with LDH nanosheets (a rigid inorganic matrix), can be applied to the simultaneous analysis of PCP and Cu(II) without interference from each other. The LBL assembled nanoarchitectures were further investigated by X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (IR), which provides insight for bifunctional sensing behavior. Under the optimized conditions, the detection limit was found to be as low as 0.4 nM PCP, well below the guideline value of PCP in drinking water (3.7 nM) set by the United States Environmental Protection Agency (U.S. EPA), and 2.0 nM Cu 2+ , much below the guideline value (2.0 mg L −1

Improved Performance of Fluorinated Copper Phthalocyanine Thin Film Transistors Using Para-hexaphenyl as the Inducing Layer

International Nuclear Information System (INIS)

Ma Feng; Wang Shi-Rong; Li Xiang-Gao; Yan Dong-Hang

2011-01-01

We demonstrate n-type organic thin film transistors (OTFTs) employing copper hexadecafluorophthalocyanine (CuPcF 16 ) as the active layer and para-hexaphenyl (p-6p) as the inducing layer. Compared with the CuPcF 16 -based OTFTs without the p-6p inducing layer, the performance of the CuPcF 16 /p-6p OTFTs is greatly improved. The charge carrier field-effect mobility μ, on-off current ratio I on /I off and threshold voltage V T of the CuPcF 16 /p-6p OTFTs are 0.07 cm 2 /V·s, 1.61 × 10 5 and 6.28 V, respectively, approaching the level of a single crystal device. The improved performance is attributed to the introduction of p-6p to form a highly oriented and continuous film of CuPcF 16 with the molecular π-π stack direction parallel to the substrate. (cross-disciplinary physics and related areas of science and technology)

Electrochemical impedance study of copper in phosphate buffered solution

International Nuclear Information System (INIS)

Salimon, J.; Mohamad, M.; Yamin, B.M.; Kalaji, M.

2003-01-01

The processes occurring on the copper electrode surface in phosphate buffered solution were investigated using the Electrochemical Impedance Spectroscopy. The electrochemical behaviors of copper through their charge transfer resistance and double-layer capacitance at the onset of the hydrogen evolution region and the anodic passivation layer formation and diffusion of copper species at anodic potential regions are discussed. The specific adsorption of anions (hydroxide and/or H/sub 2/PO/sub 4/) occurred at potential less negative than -0.9V. Adsorbed hydrogen appeared at hydrogen evolution region at potential range of -1.5 to -1.0 V. The deposition of insoluble copper species occurred at anodic potential regions. (author)

Thermal Annealing Effect on Poly(3-hexylthiophene: Fullerene:Copper-Phthalocyanine Ternary Photoactive Layer

Directory of Open Access Journals (Sweden)

H. Derouiche

2013-01-01

Full Text Available We have fabricated poly(3-hexylthiophene (P3HT/copper phthalocyanine (CuPc/fullerene (C60 ternary blend films. This photoactive layer is sandwiched between an indium tin oxide (ITO/poly(3,4-ethylenedioxythiophene:poly(styrene sulfonate (PEDOT/PSS photoanode and a bathocuproine (BCP/aluminium photocathode. The thin films have been characterized by atomic force microscope (AFM and ultraviolet/visible spectroscopy in order to study the influence of P3HT doping on the morphological and optical properties of the photoactive layer. We have also compared the characteristics of three different organic solar cells: ITO/PEDOT:PSS/CuPc0.5:C600.5/BCP/Al and ITO/PEDOT:PSS/P3HT0.3:CuPc0.3:C600.4/BCP/Al with and without annealing. Both structures show good photovoltaic behaviour. Indeed, the incorporation of P3HT into CuPc:C60 thin film improves all the photovoltaic characteristics. We have also seen that thermal annealing significantly improves the optical absorption ability and stabilizes the organic solar cells making it more robust to chemical degradation.

Electrodeposited Organic Layers Formed from Aryl Diazonium Salts for Inhibition of Copper Corrosion

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Ana Chira

2017-02-01

Full Text Available Copper substrates deposed on a gold screen-printed electrode were covered with different aryl diazonium salts by electrodeposition at 0.25 mA for 30 or 300 s. Seven compounds were investigated: 4-aminophenylacetic acid, 4-aminophenethyl alcohol, 4-fluoroaniline, 4-(heptadecafluorooctylaniline, 4-aminoantipyrine, 4-(4-aminophenylbutyric acid and 3,4,5-trimethoxyaniline. Quantitative monitoring of the electrodeposition process was carried out by electrogravimetry using quartz crystal microbalance (QCM. The electrodeposited mass varies between 26 ng/cm2 for 4-fluoroaniline formed during 30 s to 442 ng/cm2 for 4-phenylbutyric acid formed during 300 s. The corrosion inhibition properties of aryl-modified layers have been studied in buffer citrate with pH = 3 or 3.5% NaCl solutions using electrochemical noise (ECN and Tafel potentiodynamic polarization measurements. A corrosion inhibiting efficiency up to 90% was found. The highest corrosion inhibition was obtained for 4-(4-aminophenylbutyric acid and the lowest for 4-fluoroaniline. A relation between the inhibition efficiency and the chemical nature of the substituents in the protective layer was found.

Electrodeposited Organic Layers Formed from Aryl Diazonium Salts for Inhibition of Copper Corrosion.

Science.gov (United States)

Chira, Ana; Bucur, Bogdan; Radu, Gabriel-Lucian

2017-02-28

Copper substrates deposed on a gold screen-printed electrode were covered with different aryl diazonium salts by electrodeposition at 0.25 mA for 30 or 300 s. Seven compounds were investigated: 4-aminophenylacetic acid, 4-aminophenethyl alcohol, 4-fluoroaniline, 4-(heptadecafluorooctyl)aniline, 4-aminoantipyrine, 4-(4-aminophenyl)butyric acid and 3,4,5-trimethoxyaniline. Quantitative monitoring of the electrodeposition process was carried out by electrogravimetry using quartz crystal microbalance (QCM). The electrodeposited mass varies between 26 ng/cm² for 4-fluoroaniline formed during 30 s to 442 ng/cm² for 4-phenylbutyric acid formed during 300 s. The corrosion inhibition properties of aryl-modified layers have been studied in buffer citrate with pH = 3 or 3.5% NaCl solutions using electrochemical noise (ECN) and Tafel potentiodynamic polarization measurements. A corrosion inhibiting efficiency up to 90% was found. The highest corrosion inhibition was obtained for 4-(4-aminophenyl)butyric acid and the lowest for 4-fluoroaniline. A relation between the inhibition efficiency and the chemical nature of the substituents in the protective layer was found.

Effects of Au nanoparticle addition to hole transfer layer in organic solar cells based on copper naphthalocyanine and fullerene

Institute of Scientific and Technical Information of China (English)

Akihiko Nagata; Takeo Okun; Tsuyoshi Akiyaman; Atsushi Suzuki

2014-01-01

Organic solar cells based on copper naphthalocyanine (CuNc) and fullerene (C60) were fabricated, and their photovoltaic properties were investigated. C60 and CuNc were used as n-type and p-type semiconductors, respectively. In addition, the effect of Au nanoparticle addition on a hole transfer layer was investigated, and the power conversion efficiency of the devices was improved after blending the Au nanoparticles into the hole transport layer. Nanostructures of Au nanoparticles were investigated by transmission electron microscopy and X-ray diffraction. Energy levels of molecules were calculated by molecular orbital calculations, and the nanostructure and electronic properties were discussed.

Electrical conduction in composites containing copper core–copper ...

Indian Academy of Sciences (India)

Unknown

of Mott's small polaron hopping conduction model. ... sample exhibited a metallic conduction confirming the formation of a percolative chain of ..... value of εp. Also the oxide layer formation on the initially unoxidized copper particles will increase the resistivity level of the nanocomposite. This is borne out by results shown in ...

Thin-layer heap bioleaching of copper flotation tailings containing high levels of fine grains and microbial community succession analysis

Science.gov (United States)

Hao, Xiao-dong; Liang, Yi-li; Yin, Hua-qun; Liu, Hong-wei; Zeng, Wei-min; Liu, Xue-duan

2017-04-01

Thin-layer heap bioleaching of copper flotation tailings containing high levels of fine grains was carried out by mixed cultures on a small scale over a period of 210 d. Lump ores as a framework were loaded at the bottom of the ore heap. The overall copper leaching rates of tailings and lump ores were 57.10wt% and 65.52wt%, respectively. The dynamic shifts of microbial community structures about attached microorganisms were determined using the Illumina MiSeq sequencing platform based on 16S rRNA amplification strategy. The results indicated that chemolithotrophic genera Acidithiobacillus and Leptospirillum were always detected and dominated the microbial community in the initial and middle stages of the heap bioleaching process; both genera might be responsible for improving the copper extraction. However, Thermogymnomonas and Ferroplasma increased gradually in the final stage. Moreover, the effects of various physicochemical parameters and microbial community shifts on the leaching efficiency were further investigated and these associations provided some important clues for facilitating the effective application of bioleaching.

Efficient electron-induced removal of oxalate ions and formation of copper nanoparticles from copper(II oxalate precursor layers

Directory of Open Access Journals (Sweden)

Kai Rückriem

2016-06-01

Full Text Available Copper(II oxalate grown on carboxy-terminated self-assembled monolayers (SAM using a step-by-step approach was used as precursor for the electron-induced synthesis of surface-supported copper nanoparticles. The precursor material was deposited by dipping the surfaces alternately in ethanolic solutions of copper(II acetate and oxalic acid with intermediate thorough rinsing steps. The deposition of copper(II oxalate and the efficient electron-induced removal of the oxalate ions was monitored by reflection absorption infrared spectroscopy (RAIRS. Helium ion microscopy (HIM reveals the formation of spherical nanoparticles with well-defined size and X-ray photoelectron spectroscopy (XPS confirms their metallic nature. Continued irradiation after depletion of oxalate does not lead to further particle growth giving evidence that nanoparticle formation is primarily controlled by the available amount of precursor.

Giant magneto-impedance effect on nanocrystalline microwires with conductive layer deposit

International Nuclear Information System (INIS)

Wang, R.L.; Zhao, Z.J.; Liu, L.P.; Yuan, W.Z.; Yang, X.L.

2005-01-01

In this study, the giant magneto-impedance effect on Fe-based glass-coated nanocrystalline microwires with and without an additional outer copper layer was investigated. Experiment results showed that the magneto-impedance ratio of the wires with a layer of deposited copper is higher at low frequencies and lower at high frequencies (above 50 MHz), as compared to that of the microwires without an outer copper layer. The peak MI magnetic field, corresponding to the maximum of the magneto-impedance ratio shifts towards higher field values with increasing coating thickness of copper layer. The results are explained in terms of electro-magnetic interactions between the conductive layer and the ferromagnetic core

Fabrication of conductive copper patterns using reactive inkjet printing followed by two-step electroless plating

International Nuclear Information System (INIS)

Chen, Jin-Ju; Lin, Guo-Qiang; Wang, Yan; Sowade, Enrico; Baumann, Reinhard R.; Feng, Zhe-Sheng

2017-01-01

Highlights: • Copper patterns were fabricated by reactive inkjet printing and two-step electroless plating. • Cu particles produced via reactive inkjet printing act as catalyst for copper electroless plating. • High conductivity can be obtained without many printing passes and high temperature sintering. • This approach can largely avoid nozzle-clogging problems. • This approach presents a potential way in the flexible printed electronics with simple process. - Abstract: A simple and low-cost process for fabricating conductive copper patterns on flexible polyimide substrates was demonstrated. Copper catalyst patterns were first produced on polyimide substrates using reactive inkjet printing of Cu (II)-bearing ink and reducing ink, and then the conductive copper patterns were generated after a two-step electroless plating procedure. The copper layers were characterized by optical microscope, SEM, XRD and EDS. Homogeneously distributed copper nanoclusters were found in the catalyst patterns. A thin copper layer with uniform particle size was formed after first-step electroless plating, and a thick copper layer of about 14.3 μm with closely packed structure and fine crystallinity was produced after second-step electroless plating. This resulting copper layer had good solderability, reliable adhesion strength and a low resistivity of 5.68 μΩ cm without any sintering process.

Fabrication of conductive copper patterns using reactive inkjet printing followed by two-step electroless plating

Energy Technology Data Exchange (ETDEWEB)

Chen, Jin-Ju; Lin, Guo-Qiang; Wang, Yan [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054 (China); Sowade, Enrico; Baumann, Reinhard R. [Digital Printing and Imaging Technology, Technische Universität Chemnitz, Chemnitz, 09126 (Germany); Feng, Zhe-Sheng, E-mail: fzs@uestc.edu.cn [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054 (China)

2017-02-28

Highlights: • Copper patterns were fabricated by reactive inkjet printing and two-step electroless plating. • Cu particles produced via reactive inkjet printing act as catalyst for copper electroless plating. • High conductivity can be obtained without many printing passes and high temperature sintering. • This approach can largely avoid nozzle-clogging problems. • This approach presents a potential way in the flexible printed electronics with simple process. - Abstract: A simple and low-cost process for fabricating conductive copper patterns on flexible polyimide substrates was demonstrated. Copper catalyst patterns were first produced on polyimide substrates using reactive inkjet printing of Cu (II)-bearing ink and reducing ink, and then the conductive copper patterns were generated after a two-step electroless plating procedure. The copper layers were characterized by optical microscope, SEM, XRD and EDS. Homogeneously distributed copper nanoclusters were found in the catalyst patterns. A thin copper layer with uniform particle size was formed after first-step electroless plating, and a thick copper layer of about 14.3 μm with closely packed structure and fine crystallinity was produced after second-step electroless plating. This resulting copper layer had good solderability, reliable adhesion strength and a low resistivity of 5.68 μΩ cm without any sintering process.

A cytosolic copper storage protein provides a second level of copper tolerance in Streptomyces lividans.

Science.gov (United States)

Straw, Megan L; Chaplin, Amanda K; Hough, Michael A; Paps, Jordi; Bavro, Vassiliy N; Wilson, Michael T; Vijgenboom, Erik; Worrall, Jonathan A R

2018-01-24

Streptomyces lividans has a distinct dependence on the bioavailability of copper for its morphological development. A cytosolic copper resistance system is operative in S. lividans that serves to preclude deleterious copper levels. This system comprises of several CopZ-like copper chaperones and P 1 -type ATPases, predominantly under the transcriptional control of a metalloregulator from the copper sensitive operon repressor (CsoR) family. In the present study, we discover a new layer of cytosolic copper resistance in S. lividans that involves a protein belonging to the newly discovered family of copper storage proteins, which we have named Ccsp (cytosolic copper storage protein). From an evolutionary perspective, we find Ccsp homologues to be widespread in Bacteria and extend through into Archaea and Eukaryota. Under copper stress Ccsp is upregulated and consists of a homotetramer assembly capable of binding up to 80 cuprous ions (20 per protomer). X-ray crystallography reveals 18 cysteines, 3 histidines and 1 aspartate are involved in cuprous ion coordination. Loading of cuprous ions to Ccsp is a cooperative process with a Hill coefficient of 1.9 and a CopZ-like copper chaperone can transfer copper to Ccsp. A Δccsp mutant strain indicates that Ccsp is not required under initial copper stress in S. lividans, but as the CsoR/CopZ/ATPase efflux system becomes saturated, Ccsp facilitates a second level of copper tolerance.

Temperature and Copper Concentration Effects on the Formation of Graphene-Encapsulated Copper Nanoparticles from Kraft Lignin

Directory of Open Access Journals (Sweden)

Weiqi Leng

2017-06-01

Full Text Available The effects of temperature and copper catalyst concentration on the formation of graphene-encapsulated copper nanoparticles (GECNs were investigated by means of X-ray diffraction, Fourier transform infrared spectroscopy-attenuated total reflectance, and transmission electron microscopy. Results showed that higher amounts of copper atoms facilitated the growth of more graphene islands and formed smaller size GECNs. A copper catalyst facilitated the decomposition of lignin at the lowest temperature studied (600 °C. Increasing the temperature up to 1000 °C retarded the degradation process, while assisting the reconfiguration of the defective sites of the graphene layers, thus producing higher-quality GECNs.

Studies on Cementation of Tin on Copper and Tin Stripping from Copper Substrate

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Rudnik E.

2016-06-01

Full Text Available Cementation of tin on copper in acid chloride-thiourea solutions leads to the formation of porous layers with a thickness dependent on the immersion time. The process occurs via Sn(II-Cu(I mechanism. Chemical stripping of tin was carried out in alkaline and acid solutions in the presence of oxidizing agents. It resulted in the dissolution of metallic tin, but refractory Cu3Sn phase remained on the copper surface. Electrochemical tin stripping allows complete tin removal from the copper substrate, but porosity and complex phase composition of the tin coating do not allow monitoring the process in unambiguous way.

40 CFR Table 10 to Part 455 - List of Appropriate Pollution Control Technologies

Science.gov (United States)

2010-07-01

.... Arsenous acid anhydride 7001 Metallic Precipitation. Copper oxychloride 8001 Metallic Precipitation. Basic... Activated Carbon. Hydroxyethyl)-2-alkyl-2-imidazoline (as in fatty acids of t 46609 NR4 Activated Carbon...-aminopropane* (Fatty acids of coconut oil) 67301 Iminamide Activated Carbon. Alkyl* amino)-3-aminopropane *(53...

Smoothing an isolated interface of cobalt-copper under irradiation by low-energy argon ions

International Nuclear Information System (INIS)

Stognij, A.I.; Novitskij, N.N.; Stukalov, O.M.

2003-01-01

Multilayer film structures, i.e. gold layer-copper-cobalt, are considered. It is shown that the structure, where cobalt surface prior to copper layer deposition was subjected to additional irradiation by a flow of argon ions, features the smoothest surface. The conclusion is made about smoothing out of cobalt-copper interface as a result of multiple collisions of argon slow ions and cobalt atoms during braking within two or three upper atomic rows of the cobalt layer [ru

High temperature oxidation of copper and copper aluminium alloys: Impact on furnace side wall cooling systems

Science.gov (United States)

Plascencia Barrera, Gabriel

The high temperature oxidation behaviours of copper and dilute Cu-Al alloys were investigated. Experiments were carried out by: (i) Oxidizing under various oxygen potentials at different temperatures using a combined TG-DTA apparatus. (ii) Oxidizing in a muffle furnace (in air) at different temperatures for extended periods of time. The oxidation mechanisms were evaluated based upon the kinetic data obtained as well as by X-ray diffraction and microscopical (SEM and optical) analyses. It was found that oxidation of copper strongly depends on the temperature. Two distinct mechanisms were encountered. Between 300 and 500°C, the oxidation rate is controlled by lateral growth of the oxide on the metal surface, whereas between 600 and 1000°C oxidation is controlled by lattice diffusion of copper ions through the oxide scale. On the other hand, the partial pressure of oxygen only has a small effect on the oxidation of copper. Alloy oxidation is also dependent on the temperature. As temperature increases, more aluminium is required to protect copper from being oxidized. It was shown that if the amount of oxygen that dissolves in the alloy exceeds the solubility limit of oxygen in copper, an internal oxidation layer will develop, leading to the formation of a tarnishing scale. On the other hand if the oxygen content in the alloy lies below the solubility limit of oxygen in copper, no oxidation products will form since a tight protective alumina layer will form on the alloy surface. Surface phenomena may affect the oxidation behaviour of dilute Cu-Al alloys. Immersion tests in molten copper matte and copper converting slag, using laboratory scale cooling elements with various copper based materials, were conducted. Results from these tests showed that alloying copper with 3 to 4 wt% Al decreases the oxidation rate of pure copper by 4 orders of magnitude; however due to a significant drop in thermal conductivity, the ability to extract heat is compromised, leading to

Method for fabrication of ceramic dielectric films on copper foils

Science.gov (United States)

Ma, Beihai; Narayanan, Manoj; Dorris, Stephen E.; Balachandran, Uthamalingam

2015-03-10

The present invention provides a method for fabricating a ceramic film on a copper foil. The method comprises applying a layer of a sol-gel composition onto a copper foil. The sol-gel composition comprises a precursor of a ceramic material suspended in 2-methoxyethanol. The layer of sol-gel is then dried at a temperature up to about 250.degree. C. The dried layer is then pyrolyzed at a temperature in the range of about 300 to about 450.degree. C. to form a ceramic film from the ceramic precursor. The ceramic film is then crystallized at a temperature in the range of about 600 to about 750.degree. C. The drying, pyrolyzing and crystallizing are performed under a flowing stream of an inert gas. In some embodiments an additional layer of the sol-gel composition is applied onto the ceramic film and the drying, pyrolyzing and crystallizing steps are repeated for the additional layer to build up a thicker ceramic layer on the copper foil. The process can be repeated one or more times if desired.

Reactivity test between beryllium and copper

International Nuclear Information System (INIS)

Kawamura, H.; Kato, M.

1995-01-01

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)

Synthesis of copper polyacrylate nanocomposites by gamma irradiation

International Nuclear Information System (INIS)

Casalme, Loida Olores

2005-04-01

This research involves the synthesis of copper nanoparticles with controlled size by the application of gamma radiation with varying polyacrylic acid (PAA) and CuSO 4 concentration. An alternative and convenient method was done which employs Co 60 irradiation of solutions of copper salt and PAA with irradiation dose of 1.6, 3.6, 6.4, and 9.2 MRad. The effect of polymer and copper sulfate's initial concentrations as well as the effect of the presence of alcohol as radical scavenger and the presence of ethylenediaminetetraacetic acid as stabilizer were evaluated. Characterization of nanocomposite properties such as plasmon resonance band, fluorescence, and particle morphology and size were determined. Layer-by-layer assembly of Cu-PAA nanocomposites and polydiallyl dimethyl ammonium chloride (PDDA) was also constructed. Stability of the synthesized copper-PAA nanocomposites in terms of the disappearance of plasmon band with time was evaluated. (Author)

Gibbs energy calculation of electrolytic plasma channel with inclusions of copper and copper oxide with Al-base

Science.gov (United States)

Posuvailo, V. M.; Klapkiv, M. D.; Student, M. M.; Sirak, Y. Y.; Pokhmurska, H. V.

2017-03-01

The oxide ceramic coating with copper inclusions was synthesized by the method of plasma electrolytic oxidation (PEO). Calculations of the Gibbs energies of reactions between the plasma channel elements with inclusions of copper and copper oxide were carried out. Two methods of forming the oxide-ceramic coatings on aluminum base in electrolytic plasma with copper inclusions were established. The first method - consist in the introduction of copper into the aluminum matrix, the second - copper oxide. During the synthesis of oxide ceramic coatings plasma channel does not react with copper and copper oxide-ceramic included in the coating. In the second case is reduction of copper oxide in interaction with elements of the plasma channel. The content of oxide-ceramic layer was investigated by X-ray and X-ray microelement analysis. The inclusions of copper, CuAl2, Cu9Al4 in the oxide-ceramic coatings were found. It was established that in the spark plasma channels alongside with the oxidation reaction occurs also the reaction aluminothermic reduction of the metal that allows us to dope the oxide-ceramic coating by metal the isobaric-isothermal potential oxidation of which is less negative than the potential of the aluminum oxide.

Graphene-protected copper and silver plasmonics

DEFF Research Database (Denmark)

Kravets, V. G.; Jalil, R.; Kim, Y. J.

2014-01-01

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...

Nanoscale Copper and Copper Compounds for Advanced Device Applications

Science.gov (United States)

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.

Copper oxide/N-silicon heterojunction photovoltaic device

Science.gov (United States)

Feng, Tom; Ghosh, Amal K.

1982-01-01

A photovoltaic device having characteristics of a high efficiency solar cell comprising a Cu.sub.x O/n-Si heterojunction. The Cu.sub.x O layer is formed by heating a deposited copper layer in an oxygen containing ambient.

Simulation of the Dynamics of Isothermal Growth of Single-Layer Graphene on a Copper Catalyst in the Process of Chemical Vapor Deposition of Hydrocarbons

Science.gov (United States)

Futko, S. I.; Shulitskii, B. G.; Labunov, V. A.; Ermolaeva, E. M.

2018-01-01

A new kinetic model of isothermal growth of single-layer graphene on a copper catalyst as a result of the chemical vapor deposition of hydrocarbons on it at a low pressure has been developed on the basis of in situ measurements of the growth of graphene in the process of its synthesis. This model defines the synthesis of graphene with regard for the chemisorption and catalytic decomposition of ethylene on the surface of a copper catalyst, the diffusion of carbon atoms in the radial direction to the nucleation centers within the thin melted near-surface copper layer, and the nucleation and autocatalytic growth of graphene domains. It is shown that the time dependence of the rate of growth of a graphene domain has a characteristic asymmetrical bell-like shape. The dependences of the surface area and size of a graphene domain and the rate of its growth on the time at different synthesis temperatures and ethylene concentrations have been obtained. Time characteristics of the growth of graphene domains depending on the parameters of their synthesis were calculated. The results obtained can be used for determining optimum regimes of synthesis of graphene in the process of chemical vapor deposition of hydrocarbons on different catalysts with a low solubility of carbon.

Formation of CuxS Layers on Polypropylene Sulfurized by Molten Sulfur

Directory of Open Access Journals (Sweden)

Rasa ALABURDAITĖ

2011-11-01

Full Text Available The processes of formation of electrically conductive layers of copper sulfides CuxS by the sorption-diffusion method on polypropylene (PP using molten sulfur as sulfurizing agent was investigated. The amount of sorbed sulfur increased with the increase of the duration of treatment. Copper sulfide layers were formed on the surface of polypropylene after the treatment of sulfurized polymer with Cu(II/I salt solution. The amount of copper sulfide in layer increased with the increase of treatment duration in copper salt solution. XRD spectra of PP films treated for 3 min with molten sulfur and then with Cu(II/I salt solution for the different time showed that the copper sulfide phases, mostly digenite, Cu2-xS and a-chalcocite, Cu2S were formed in the layers. Electromotive force measurement results confirmed the composition of formed CuxS layers on PP. The phase composition of layers also changed after the annealing. The value of electrical resistance of copper sulfide layers on PP varied from 20 W/cm2 to 80 W/cm2 and after annealing at 80 °C - in the interval of 10 W/cm2 - 60 W/cm2.http://dx.doi.org/10.5755/j01.ms.17.4.776

Modification of surface layers of copper under the action of the volumetric discharge initiated by an avalanche electron beam in nitrogen and CO2 at atmospheric pressure

Science.gov (United States)

Shulepov, M. A.; Akhmadeev, Yu. Kh.; Tarasenko, V. F.; Kolubaeva, Yu. A.; Krysina, O. V.; Kostyrya, I. D.

2011-05-01

The results of experimental investigations of the action of the volumetric discharge initiated by an avalanche electron beam on the surface of copper specimens are presented. The volumetric (diffuse) discharge in nitrogen and CO2 at atmospheric pressure was initiated by applying high voltage pulses of nanosecond duration to a tubular foil cathode. It has been found that the treatment of a copper surface by this type of discharge increases the hardness of the surface layer due to oxidation.

Controlling the Performance of P-type Cu2O/SnO Bilayer Thin-Film Transistors by Adjusting the Thickness of the Copper Oxide Layer

KAUST Repository

Al-Jawhari, Hala A.

2014-11-11

The effect of copper oxide layer thickness on the performance of Cu2O/SnO bilayer thin-film transistors was investigated. By using sputtered Cu2O films produced at an oxygen partial pressure, Opp, of 10% as the upper layer and 3% Opp SnO films as the lower layer we built a matrix of bottom-gate Cu2O/SnO bilayer thin-film transistors of different thickness. We found that the thickness of the Cu2O layer is of major importance in oxidation of the SnO layer underneath. The thicker the Cu2O layer, the more the underlying SnO layer is oxidized, and, hence, the more transistor mobility is enhanced at a specific temperature. Both device performance and the annealing temperature required could be adjusted by controlling the thickness of each layer of Cu2O/SnO bilayer thin-film transistors.

Potassium sorbate-A new aqueous copper corrosion inhibitor

International Nuclear Information System (INIS)

Abelev, Esta; Starosvetsky, David; Ein-Eli, Yair

2007-01-01

This work presents the novel nature of 2,4-hexadienoic acid potassium salt (potassium sorbate (KCH 3 CH=CHCH=CHCO 2 )) as an effective copper aqueous corrosion inhibitor. The influence of pH and potassium sorbate concentration on copper corrosion in aerated sulfate and chloride solutions is reported. Degree of copper protection was found to increase with an increase in potassium sorbate concentration; an optimum concentration of this inhibitor in sulfate solutions was found to be 10 g/L. Copper is highly resistant to corrosion attacks by chloride ions in the presence of potassium sorbate. X-ray photoelectron spectroscopy (XPS) studies suggest that copper protection is achieved via the formation of a mixed layer of cuprous oxide, cupric hydroxide and copper(II)-sorbate at the metal surface

Electron emission from a double-layer metal under femtosecond laser irradiation

Energy Technology Data Exchange (ETDEWEB)

Li, Shuchang; Li, Suyu; Jiang, Yuanfei; Chen, Anmin, E-mail: amchen@jlu.edu.cn; Ding, Dajun; Jin, Mingxing, E-mail: mxjin@jlu.edu.cn

2015-01-01

In this paper we theoretically investigate electron emission during femtosecond laser ablation of single-layer metal (copper) and double-layer structures. The double-layer structure is composed of a surface layer (copper) and a substrate layer (gold or chromium). The calculated results indicate that the double-layer structure brings a change to the electron emission from the copper surface. Compared with the ablation of a single-layer, a double-layer structure may be helpful to decrease the relaxation time of the electron temperature, and optimize the electron emission by diminishing the tailing phenomenon under the same absorbed laser fluence. With the increase of the absorbed laser fluence, the effect of optimization becomes significant. This study provides a way to optimize the electron emission which can be beneficial to generate laser induced ultrafast electron pulse sources.

Influence of cutting parameters on the depth of subsurface deformed layer in nano-cutting process of single crystal copper.

Science.gov (United States)

Wang, Quanlong; Bai, Qingshun; Chen, Jiaxuan; Su, Hao; Wang, Zhiguo; Xie, Wenkun

2015-12-01

Large-scale molecular dynamics simulation is performed to study the nano-cutting process of single crystal copper realized by single-point diamond cutting tool in this paper. The centro-symmetry parameter is adopted to characterize the subsurface deformed layers and the distribution and evolution of the subsurface defect structures. Three-dimensional visualization and measurement technology are used to measure the depth of the subsurface deformed layers. The influence of cutting speed, cutting depth, cutting direction, and crystallographic orientation on the depth of subsurface deformed layers is systematically investigated. The results show that a lot of defect structures are formed in the subsurface of workpiece during nano-cutting process, for instance, stair-rod dislocations, stacking fault tetrahedron, atomic clusters, vacancy defects, point defects. In the process of nano-cutting, the depth of subsurface deformed layers increases with the cutting distance at the beginning, then decreases at stable cutting process, and basically remains unchanged when the cutting distance reaches up to 24 nm. The depth of subsurface deformed layers decreases with the increase in cutting speed between 50 and 300 m/s. The depth of subsurface deformed layer increases with cutting depth, proportionally, and basically remains unchanged when the cutting depth reaches over 6 nm.

An evaluation of some fungicides in the management of fruit and leaf ...

African Journals Online (AJOL)

Four fungicide treatments viz Ben late (Benomyl), Cupravit (Copper oxychloride), Dithane M45 (Mancozeb), and. Ben late alternated with Dithane M45 were applied to control P!laeoramularia angolensi~ In a block of the variety. "Valencia" in the citrus orchard at Kiige, Uganda. No fungicide was applied to the control.

Evaluation of fungicides for the control of false smut of rice caused ...

African Journals Online (AJOL)

Benomyl, Copper Oxychloride, Iprodione, Thiabendazole (TBZ) and Mancozeb were evaluated both in the laboratory and field study in 1994, for the control of false smut of rice caused by Ustilaginoidea virens (Cooke) Tak. in upland rice in Edo State, Nigeria. In the laboratory the fungicides were evaluated at three ...

Composite sheet made of molybdenum and dispersion-strengthened copper

International Nuclear Information System (INIS)

Nicholson, R.D.; Fusco, R.S.

1990-01-01

This patent describes a roll-bonded composite sheet product having at least one layer of dispersion-strengthened copper and at least one layer of molybdenum. The composite is characterized by a sharply defined, cleavage-resistant interface between the copper and the molybdenum with substantially no detectable diffusion of one metal into the other across the interface. The composite is resistant to delamination and being capable of maintaining structural integrity upon repeated high temperature firings at temperatures up to 900 degrees C

Low-cost copper complexes as p-dopants in solution processable hole transport layers

Energy Technology Data Exchange (ETDEWEB)

Kellermann, Renate [Department for Materials Science and Engineering, Chair for Materials for Electronics and Energy Technology, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen 91058 (Germany); Siemens AG – Corporate Technology, Guenther-Scharowsky-Str. 1, Erlangen 91058 (Germany); Taroata, Dan; Maltenberger, Anna; Hartmann, David; Schmid, Guenter [Siemens AG – Corporate Technology, Guenther-Scharowsky-Str. 1, Erlangen 91058 (Germany); Brabec, Christoph J. [Department for Materials Science and Engineering, Chair for Materials for Electronics and Energy Technology, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen 91058 (Germany)

2015-09-07

We demonstrate the usage of the Lewis-acidic copper(II)hexafluoroacetylacetonate (Cu(hfac){sub 2}) and copper(II)trifluoroacetylacetonate (Cu(tfac){sub 2}) as low-cost p-dopants for conductivity enhancement of solution processable hole transport layers based on small molecules in organic light emitting diodes (OLEDs). The materials were clearly soluble in mixtures of environmentally friendly anisole and xylene and spin-coated under ambient atmosphere. Enhancements of two and four orders of magnitude, reaching 4.0 × 10{sup −11} S/cm with a dopant concentration of only 2 mol% Cu(hfac){sub 2} and 1.5 × 10{sup −9} S/cm with 5 mol% Cu(tfac){sub 2} in 2,2′,7,7′-tetra(N,N-ditolyl)amino-9,9-spiro-bifluorene (spiro-TTB), respectively, were achieved. Red light emitting diodes were fabricated with reduced driving voltages and enhanced current and power efficiencies (8.6 lm/W with Cu(hfac){sub 2} and 5.6 lm/W with Cu(tfac){sub 2}) compared to the OLED with undoped spiro-TTB (3.9 lm/W). The OLED with Cu(hfac){sub 2} doped spiro-TTB showed an over 8 times improved LT{sub 50} lifetime of 70 h at a starting luminance of 5000 cd/m{sup 2}. The LT{sub 50} lifetime of the reference OLED with PEDOT:PSS was only 8 h. Both non-optimized OLEDs were operated at similar driving voltage and power efficiency.

Silver-Copper Nanoalloy Catalyst Layer for Bifunctional Air Electrodes in Alkaline Media.

Science.gov (United States)

Wu, Xiaoqiang; Chen, Fuyi; Jin, Yachao; Zhang, Nan; Johnston, Roy L

2015-08-19

A carbon-free and binder-free catalyst layer composed of a Ag-Cu nanoalloy on Ni foam was used as the air cathode in a zinc-air battery for the first time. The Ag-Cu catalyst was prepared using pulsed laser deposition. The structures of the catalysts were found to consist of crystalline Ag-Cu nanoalloy particles with an average size of 2.58 nm embedded in amorphous Cu films. As observed in the X-ray photoelectron spectra, the Ag 3d core levels shifted to higher binding energies, whereas the Cu 2p core levels shifted to lower binding energies, indicating alloying of the silver and copper. Rotating disk electrode measurements indicated that the oxygen reduction reaction (ORR) proceeded through a four-electron pathway on the Ag50Cu50 and Ag90Cu10 nanoalloy catalysts in alkaline solution. Moreover, the catalytic activity of Ag50Cu50 in the ORR is more efficient than that of Ag90Cu10. By performing charge and discharge cycling measurements, the Ag50Cu50 catalyst layer was confirmed to have a maximum power density of approximately 86.3 mW cm(-2) and an acceptable cell voltage at 0.863 V for current densities up to 100 mA cm(-2) in primary zinc-air batteries. In addition, a round-trip efficiency of approximately 50% at a current density of 20 mA cm(-2) was also obtained in the test.

Atomic-layer-deposited WNxCy thin films as diffusion barrier for copper metallization

Science.gov (United States)

Kim, Soo-Hyun; Oh, Su Suk; Kim, Ki-Bum; Kang, Dae-Hwan; Li, Wei-Min; Haukka, Suvi; Tuominen, Marko

2003-06-01

The properties of WNxCy films deposited by atomic layer deposition (ALD) using WF6, NH3, and triethyl boron as source gases were characterized as a diffusion barrier for copper metallization. It is noted that the as-deposited film shows an extremely low resistivity of about 350 μΩ cm with a film density of 15.37 g/cm3. The film composition measured from Rutherford backscattering spectrometry shows W, C, and N of ˜48, 32, and 20 at. %, respectively. Transmission electron microscopy analyses show that the as-deposited film is composed of face-centered-cubic phase with a lattice parameter similar to both β-WC1-x and β-W2N with an equiaxed microstructure. The barrier property of this ALD-WNxCy film at a nominal thickness of 12 nm deposited between Cu and Si fails only after annealing at 700 °C for 30 min.

3D-copper oxide and copper oxide/few-layer graphene with screen printed nanosheet assembly for ultrasensitive non-enzymatic glucose sensing

Energy Technology Data Exchange (ETDEWEB)

Zhang, Zhimei [Tianjin Key Laboratory of Film Electronic and Communicate Devices, School of Electronics Information Engineering, Tianjin University of Technology, Tianjin, 300384 (China); Advanced Materials and Printed Electronics Center, School of Electronics Information Engineering, Tianjin University of Technology, Tianjin, 300384 (China); Pan, Peng, E-mail: panpeny@163.com [Tianjin Key Laboratory of Film Electronic and Communicate Devices, School of Electronics Information Engineering, Tianjin University of Technology, Tianjin, 300384 (China); Advanced Materials and Printed Electronics Center, School of Electronics Information Engineering, Tianjin University of Technology, Tianjin, 300384 (China); Liu, Xuewen [Tianjin Key Laboratory of Film Electronic and Communicate Devices, School of Electronics Information Engineering, Tianjin University of Technology, Tianjin, 300384 (China); Advanced Materials and Printed Electronics Center, School of Electronics Information Engineering, Tianjin University of Technology, Tianjin, 300384 (China); Yang, Zhengchun; Wei, Jun [Advanced Materials and Printed Electronics Center, School of Electronics Information Engineering, Tianjin University of Technology, Tianjin, 300384 (China); Wei, Zhen, E-mail: weizhenxinxi@163.com [Tianjin Key Laboratory of Film Electronic and Communicate Devices, School of Electronics Information Engineering, Tianjin University of Technology, Tianjin, 300384 (China); Advanced Materials and Printed Electronics Center, School of Electronics Information Engineering, Tianjin University of Technology, Tianjin, 300384 (China)

2017-02-01

Screen-printed copper oxide (CuO) and CuO/few-layer graphene on graphite electrodes were used to fabricate the ultrasensitive nonenzymatic glucose biosensors. Flower-like CuO and flower-like CuO/few-layer graphene composites were prepared by screen-printing method and characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and high-resolution transmission electron microscopy (HETEM). On the basis of their cyclic voltammetry (CV) and chronoamperometry results, it was concluded that the addition of graphene to CuO significantly improved the performance of the fabricated glucose sensors, exhibiting high and reproducible sensitivity of 3120 μAmM{sup −1} cm{sup −2} with three linear ranges from 4 μM to 13.5 mM and the detection limit of 4 μM (S/N = 3) in a fast response time of 2 s. In addition, the fabricated sensors could effectively avoid the disturbance by interferents, such as Ascorbic Acid (AA), Uric Acid (UA), and Dopamine (DA). Most importantly, the testing results of real blood serum samples demonstrated that the electrodes were applicable and acceptable for the determination of glucose concentrations in human serum. The efficiencies of two non-enzymatic glucose biosensors for glucose determination were comparable with that of a commercial enzymatic sensor. - Highlights: • The method 2D nanosheet turns to 3D microflower by using screen printing was proposed. • Few-layer graphene added improved the sensor’s performance on base of CuO functional material. • Two ultrasensitive non-enzymatic glucose sensors were successfully fabricated. • The proposed sensor shows a high sensitivity of 3120 μA mM{sup −1} cm{sup −2}.

Oxygen Reduction Reaction for Generating H2 O2 through a Piezo-Catalytic Process over Bismuth Oxychloride.

Science.gov (United States)

Shao, Dengkui; Zhang, Ling; Sun, Songmei; Wang, Wenzhong

2018-02-09

Oxygen reduction reaction (ORR) for generating H 2 O 2 through green pathways have gained much attention in recent years. Herein, we introduce a piezo-catalytic approach to obtain H 2 O 2 over bismuth oxychloride (BiOCl) through an ORR pathway. The piezoelectric response of BiOCl was directly characterized by piezoresponse force microscopy (PFM). The BiOCl exhibits efficient catalytic performance for generating H 2 O 2 (28 μmol h -1 ) only from O 2 and H 2 O, which is above the average level of H 2 O 2 produced by solar-to-chemical processes. A piezo-catalytic mechanism was proposed: with ultrasonic waves, an alternating electric field will be generated over BiOCl, which can drive charge carriers (electrons) to interact with O 2 and H 2 O, then to form H 2 O 2 . © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Copper implantation defects in MgO observed by positron beam analysis, RBS and X-TEM

International Nuclear Information System (INIS)

Huis, M.A. van; Fedorov, A.V.; Veen, A. van; Smulders, P.J.M.; Kooi, B.J.; Hosson, J.Th.M. de

2000-01-01

In this work, effects of copper ion implantation in MgO were studied. (1 0 0) MgO samples were implanted with 50 keV Cu ions and thermally annealed stepwise in air for 30 minutes at 550, 750, 1000, 1250 and 1350 K. After ion implantation and after each annealing step, the samples were analysed with positron beam analysis (PBA). Use was also made of Rutherford backscattering spectrometry/channeling (RBS-C) and cross-sectional transmission electron microscopy (X-TEM). The combination of these techniques enabled to monitor the depth resolved evolution of both created defects and the copper atom depth distribution. PBA results show that copper implantation at a dose of 10 15 ions cm -2 yields a single layer of vacancy type defects after annealing. However a copper implantation at a dose of 10 16 ions cm -2 clearly yields two layers of defects in the material after annealing, separated by an intermediate layer. In both layers nanocavities have been identified. RBS experimental results show that the implanted copper atoms diffuse into the bulk material during annealing. X-TEM and channeling results show that after annealing, the lattice of the copper nanoprecipitates is epitaxial to the MgO host lattice. Under some circumstances, copper precipitates and small voids can co-exist. Furthermore, X-TEM measurements show that the nanocavities have rectangular shapes

Barrier layer arrangement for conductive layers on silicon substrates

International Nuclear Information System (INIS)

Hung, L.S.; Agostinelli, J.A.

1990-01-01

This patent describes a circuit element comprised of a silicon substrate and a conductive layer located on the substrate. It is characterized in that the conductive layer consists essentially of a rare earth alkaline earth copper oxide and a barrier layer triad is interposed between the silicon substrate and the conductive layer comprised of a first triad layer located adjacent the silicon substrate consisting essentially of silica, a third triad layer remote from the silicon substrate consisting essentially of a least one Group 4 heavy metal oxide, and a second triad layer interposed between the first and third triad layers consisting essentially of a mixture of silica and at lease one Group 4 heavy metal oxide

Austenitic stainless steels and high strength copper alloys for fusion components

International Nuclear Information System (INIS)

Rowcliffe, A.F.; Zinkle, S.J.; Alexander, D.J.; Stubbins, J.F.

1998-01-01

An austenitic stainless steel (316LN), an oxide-dispersion-strengthened copper alloy (GlidCop A125), and a precipitation-hardened copper alloy (Cu-Cr-Zr) are the primary structural materials for the ITER first wall/blanket and divertor systems. While there is a long experience of operating 316LN stainless steel in nuclear environments, there is no prior experience with the copper alloys in neutron environments. The ITER first wall (FW) consists of a stainless steel shield with a copper alloy heat sink bonded by hot isostatic pressing (HIP). The introduction of bi-layer structural material represents a new materials engineering challenge; the behavior of the bi-layer is determined by the properties of the individual components and by the nature of the bond interface. The development of the radiation damage microstructure in both classes of materials is summarized and the effects of radiation on deformation and fracture behavior are considered. The initial data on the mechanical testing of bi-layers indicate that the effectiveness of GlidCop A125 as a FW heat sink material is compromised by its strongly anisotropic fracture toughness and poor resistance to crack growth in a direction parallel to the bi-layer interface. (orig.)

Atomic-layer-deposited WNxCy thin films as diffusion barrier for copper metallization

International Nuclear Information System (INIS)

Kim, Soo-Hyun; Oh, Su Suk; Kim, Ki-Bum; Kang, Dae-Hwan; Li, Wei-Min; Haukka, Suvi; Tuominen, Marko

2003-01-01

The properties of WN x C y films deposited by atomic layer deposition (ALD) using WF 6 , NH 3 , and triethyl boron as source gases were characterized as a diffusion barrier for copper metallization. It is noted that the as-deposited film shows an extremely low resistivity of about 350 μΩ cm with a film density of 15.37 g/cm 3 . The film composition measured from Rutherford backscattering spectrometry shows W, C, and N of ∼48, 32, and 20 at. %, respectively. Transmission electron microscopy analyses show that the as-deposited film is composed of face-centered-cubic phase with a lattice parameter similar to both β-WC 1-x and β-W 2 N with an equiaxed microstructure. The barrier property of this ALD-WN x C y film at a nominal thickness of 12 nm deposited between Cu and Si fails only after annealing at 700 deg. C for 30 min

Metallicity of Ca{sub 2}Cu{sub 6}P{sub 5} with single and double copper-pnictide layers

Energy Technology Data Exchange (ETDEWEB)

Li, Li, E-mail: lil2@ornl.gov [Materials Science & Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Parker, David [Materials Science & Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Chi, Miaofang [Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Tsoi, Georgiy M.; Vohra, Yogesh K. [Department of Physics, University of Alabama at Birmingham, Birmingham, AL 35294 (United States); Sefat, Athena S., E-mail: sefata@ornl.gov [Materials Science & Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States)

2016-06-25

We report thermodynamic and transport properties, and also theoretical calculations, for Cu-based compound Ca{sub 2}Cu{sub 6}P{sub 5} and compare with CaCu{sub 2-δ}P{sub 2}. Both materials have layers of edge-sharing copper pnictide tetrahedral CuP{sub 4}, similar to Fe–As and Fe–Se layers (with FeAs{sub 4}, FeSe{sub 4}) in the iron-based superconductors. Despite the presence of this similar transition-metal pnictide layer, we find that both Ca{sub 2}Cu{sub 6}P{sub 5} and CaCu{sub 2-δ}P{sub 2} have temperature-independent magnetic susceptibility and show metallic behavior with no evidence of either magnetic ordering or superconductivity down to 1.8 K CaCu{sub 2-δ}P{sub 2} is slightly off-stoichiometric, with δ = 0.14. Theoretical calculations suggest that unlike Fe 3d-based magnetic materials with a large density of states (DOS) at the Fermi surface, Cu have comparatively low DOS, with the majority of the 3d spectral weight located well below Fermi level. The room-temperature resistivity value of Ca{sub 2}Cu{sub 6}P{sub 5} is only 9 μΩ-cm, due to a substantial plasma frequency and an inferred electron-phonon coupling λ of 0.073 (significantly smaller than that of metallic Cu). Also, microscopy result shows that Cu–Cu distance along the c-axis within the double layers can be very short (2.5 Å), even shorter than metallic elemental copper bond (2.56 Å). The value of dρ/dT for CaCu{sub 2-δ}P{sub 2} at 300 K is approximately three times larger than in Ca{sub 2}Cu{sub 6}P{sub 5}, which suggests the likelihood of stronger electron-phonon coupling. This study shows that the details of Cu–P layers and bonding are important for their transport characteristics. In addition, it emphasizes the remarkable character of the DOS of ‘122’ iron-based materials, despite much structural similarities. - Highlights: • A comprehensive study on Cu-based compound Ca{sub 2}Cu{sub 6}P{sub 5} and compare with CaCu{sub 2-δ}P{sub 2}. • Both materials have layers of

Adhesion of metals to LaCrO3 by copper sulphide method

International Nuclear Information System (INIS)

Ebata, Yoshihiro; Toibana, Yasuo; Uetsuki, Tsuneo; Kose, Saburo; Kataoka, Nagamasa

1979-01-01

A method of adhering metallic copper to LaCrO 3 was researched using mixtures of copper sulphide and kaolin as the coponent of metalliser to obtain optimum condition for the adhesion. As a maximum adhesive strength, 300 kg/cm 2 has been attained with the metallised intermediate layer which was composed of 70 wt% copper sulphide and 30 wt% kaolin, and fired at 1000 0 C. The adhesive strength was not affected by soaking the specimen into 48% KOH solution at 70 0 C for 70 hr. Electric resistance of the desirable specimen metallised with Cu 2 S- kaolin layer and silver-paint was 1.4 times higher than that of the one coated with silver-paint only. Investigating into the fired intermediate layer by means of X-ray diffraction and EPMA, it has been confirmed that the layer partly transformed to a phase of spinel of Al 2 O 3 with CuO. Thickness of the layer penetrated into the LaCrO 3 substratum was about 50 - 60 μm. (author)

Ketahanan Beberapa Jamur Patogen terhadap Fungisida

Directory of Open Access Journals (Sweden)

Christanti Sumardiyono

1995-12-01

Full Text Available Chemical control of plant pathogens have been done for a long time using contact and systemic fungicides. Resistance of the pathogens to fungicides may caused failure of disease control program. Studies by in vitro, in green house and fields were done at Yogyakarta to know the fungal which were resistant to several fungicides after treatment. The pathogen tested to fungicides were Colletotrichum capsici on red pepper to propineb, mancozeb, mixture of carbendazim and mancozeb, and thiophanate methyl, Alternaria porri on garlic to thiophanate methyl, Phytophthora palmivora on cocoa to Al-fosetyl, metalaxyl, mancozeb, and Copper Oxychloride, and Peronosclerospora maydis on corn to metalaxyl. The study indicated that C. capsici was resistant to propineb, mancozeb, and mixture of carbendazim and mancozeb, but sensitive to thiophanate methyl. A. porri from plant treated with thiophanate methyl indicated resistant to the fungicides. ED50 of Al-fosetyl and metalaxyl on P. palmivora were higher than on mancozeb and copper oxychloride, so that it was resistance strain. Key words: contact fungicides, systemic fungicides, resistance

Side effects of some pesticides on the silverleaf whitefly’s parasitoid, Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae under laboratory conditions

Directory of Open Access Journals (Sweden)

Mustafa PORTAKALDALI

2015-12-01

Full Text Available The silverleaf whitefly, Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae is one of major pests in greenhouses vegetable cultivation. Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae has an important role among effective parasitoids used in biological control of the silverleaf whitefly. Nondestructive or less destructive pesticides against this parasitoid should be preferred in the scope of biological control. For this goal, side effects of 8 plant protection products, including spinosad, pyriproxyfen, abamectin, emamectin benzoate, copper oxychloride, kresoxim-methyl+boscalid, dimethoate and propineb+cymoxanil on pupae and adults of E. mundus were tested in this laboratory study conducted according to IOBC standards. As a result, pesticides containing spinosad, abamectin and dimethoate were determined as highly destructive to pupae and adults of E. mundus, and pesticide containing emamectin benzoate was found as moderately harmful. As for propineb+cymoxanil, pyriproxyfen, kresoxim-methyl+boscalid and copper oxychloride, they were determined as ineffective on the parasitoid under laboratory conditions. These results obtained from experiments that were conducted under laboratory conditions also have to be supported by field or semi-field experiment’s results.

Brazing open cell reticulated copper foam to stainless steel tubing with vacuum furnace brazed gold/indium alloy plating

Science.gov (United States)

Howard, Stanley R [Windsor, SC; Korinko, Paul S [Aiken, SC

2008-05-27

A method of fabricating a heat exchanger includes brush electroplating plated layers for a brazing alloy onto a stainless steel tube in thin layers, over a nickel strike having a 1.3 .mu.m thickness. The resultant Au-18 In composition may be applied as a first layer of indium, 1.47 .mu.m thick, and a second layer of gold, 2.54 .mu.m thick. The order of plating helps control brazing erosion. Excessive amounts of brazing material are avoided by controlling the electroplating process. The reticulated copper foam rings are interference fit to the stainless steel tube, and in contact with the plated layers. The copper foam rings, the plated layers for brazing alloy, and the stainless steel tube are heated and cooled in a vacuum furnace at controlled rates, forming a bond of the copper foam rings to the stainless steel tube that improves heat transfer between the tube and the copper foam.

Chemical durability of copper canisters under crystalline bedrock repository conditions

International Nuclear Information System (INIS)

Sjoeblom, R.; Hermansson, H.P.; Amcoff, Oe.

1995-01-01

In the Swedish waste management programme, the copper canister is expected to provide containment of the radionuclides for a very long time, perhaps million of years. The purpose of the present paper is to analyze prerequisites for assessments of corrosion lifetimes for copper canisters. The analysis is based on compilations of literature from the following areas: chemical literature on copper and copper corrosion, mineralogical literature with emphasis on the stability of copper in near surface environments, and chemical and mineralogical literature with emphasis on the stabilities and thermodynamics of species and phases that may exist in a repository environment. Three main types of situations are identified: (1) under oxidizing and low chloride conditions, passivating oxide type of layers may form on the copper surface; (2) under oxidizing and high chloride conditions, the species formed may all be dissolved; and (3) under reducing conditions, non-passivating sulfide type layers may form on the copper surface. Considerable variability and uncertainty exists regarding the chemical environment for the canister, especially in certain scenarios. Thus, the mechanisms for corrosion can be expected to differ greatly for different situations. The lifetime of a thick-walled copper canister subjected to general corrosion appears to be long for most reasonable chemistries. Localized corrosion may appear for types (1) and (3) above but the mechanisms are widely different in character. The penetration caused by localized corrosion can be expected to be very sensitive to details in the chemistry. 20 refs, 3 figs, 1 tab

Preparation and structure of carbon encapsulated copper nanoparticles

International Nuclear Information System (INIS)

Hao Chuncheng; Xiao Feng; Cui Zuolin

2008-01-01

Carbon-encapsulated copper nanoparticles were synthesized by a modified arc plasma method using methane as carbon source. The particles were characterized in detail by transmission electron microscope, high-resolution transmission electron microscopy, selected-area electron diffraction, X-ray diffraction, thermogravimetric and differential scanning calorimetry. The encapsulated copper nanoparticles were about 30 nm in diameter with 3-5 nm graphitic carbon shells. The outside graphitic carbon layers effectively prevented unwanted oxidation of the copper inside. The effect of the ratio of He/CH 4 on the morphologies and the formation of the carbon shell were investigated

Appearance property and mechanism of plume produced by pulsed ultraviolet laser ablating copper

International Nuclear Information System (INIS)

Huang Qingju; Li Fuquan; Wang Honghua

2008-01-01

Time-resolved measurements of plume emission spectra by pulsed ultraviolet laser ablating copper in neon were analyzed, and the photographs of plume from laser ablating copper were taken. The experimental results show that plume has different colours in different ranges. At low pressure the centre layer and middle layer colours of plume are mixed colour, and the outer layer colours of plume are yellow and green. At middle pressure the centre layer and middle layer colours of plume are white, and the outer layer colour of plume is pea green. At high pressure the centre layer and middle layer colours of plume are white, and the outer layer colour of plume is faintness green. The plume range is pressed with the rising of ambient gas pressure, and the range colour gets thin with the rising of ambient gas pressure. The plume excitation radiation mechanism in pulsed ultraviolet laser ablating copper was discussed. The primary excitation radiation mechanism in plume is electron collision energy transfer and atom collision energy transfer at low pressure and middle pressure, and it is electrons Bremsstrahlung and recombination excitation radiation of electron and ion at high pressure. The model can be used to explain the experimental result qualitatively. (authors)

A preliminary study on coloring mechanism of Jun copper red glaze

International Nuclear Information System (INIS)

Tian Shibing; Liu Yuzhen; Zhang Maolin; Wang Lihua; Wang Cangsui; Xie Yaning

2009-01-01

The origin of a red color glazes decorated on the ancient Jun porcelain has been attributed to the presence of combined copper clusters and cuprous oxide, or cuprous oxide alone. For better understanding of the color-forming mechanism, X-ray absorption at the Cu-edge by the red area of a Jun porcelain shard was carried out. By comparing the XANFS spectra of the sample with metal copper and cubic Cu 2 O, we found that the spectra of the red layer of sample were similar to the spectrum combination of 37% Cu 2 O and 63% metal copper,while the spectra from surface of the red spot mainly resembled that of cubic Cu 2 O. The EXAFS results showed that monovalence copper cations were isolated in the glaze matrix, and copper atoms were formed to metallic copper clusters or mutimers dominantly distributed in the inner layer. These can be responsible to the optical properties of the red decoration with the presence of colloidal composition containing copper particles and the Cu + ions. In conclusion, a preliminary non-destructive elemental analysis using synchrotron radiation-induce X-ray fluorescence (SR-XRF) is demonstrated, and mechanism about the formation of the complicated structures is discussed. (authors)

Effects of plasma cleaning of the Cu seed layer surface on Cu electroplating

International Nuclear Information System (INIS)

O, Jun Hwan; Lee, Seong Wook; Kim, Jae Bum; Lee, Chong Mu

2001-01-01

Effects of plasma pretreatment to Cu seed/tantalum nitride (TaN)/ borophosphosilicate glass (BPSG) samples on copper (Cu) electroplating were investigated. Copper seed layers were deposited by magnetron sputtering onto tantalum nitride barrier layers before electroplating copper in the forward pulsed mode. The Cu seed layer was cleaned by plasma H 2 and N 2 prior to electroplating a copper film. Cu films electroplated on the copper seed layer with plasma pretreatment showed better electrical and physical properties such as electrical resistivities, surface morphologies, levels of impurities, adhesion and surface roughness than those without plasma pretreatment. It is shown that carbon and metal oxide contaminants at the sputtered Cu seed/TaN surface could be effectively removed by plasma H 2 cleaning. The degree of the (111) prefered orientation of the Cu film with plasma H 2 pretreatment is as high as pulse plated Cu film without plasma pretreatment. Also, plasma H 2 precleaning is more effective in enhancing the Cu electroplating properties onto the Cu seed layer than plasma N 2 precleaning

Effect of corrosion product layer on SCC susceptibility of copper containing type 304 stainless steel in 1 M H2SO4

International Nuclear Information System (INIS)

Asawa, M.; Devasenapathi, A.; Fujisawa, M.

2004-01-01

The effect of surface corrosion product layer on the stress corrosion cracking (SCC) susceptibility of type 304 stainless steel with Cu was studied in 1 kmol/m 3 (1 M) sulfuric acid at 353 K temperature. Studies based on the intermittent removal of surface corrosion product layer indicated that the surface film governs the SCC behavior of the alloy by accelerating both the crack initiation and propagation stages. The electrochemical impedance and polarization studies showed the surface layer to be promoting SCC initiation by lowering the uniform corrosion rate and the propagation by shifting the surface corrosion potential to a more noble direction. The elemental analysis of the corrosion product both by the energy dispersive X-ray (EDX) spectroscopy and by X-ray diffraction (XRD) analysis along with the thermodynamic calculations showed the layer to be constituted mainly of metallic copper (Cu) and the mono-hydrated iron sulfate which acts as cathode promoting SCC

Local thermal property analysis by scanning thermal microscopy of an ultrafine-grained copper surface layer produced by surface mechanical attrition treatment

Energy Technology Data Exchange (ETDEWEB)

Guo, F.A. [Suzhou Institute for Nonferrous Metals Processing Technology, No. 200 Shenxu Road, Suzhou Industrial Park, Suzhou 215021 (China) and Unite de Thermique et d' Analyse Physique, Laboratoire d' Energetique et d' Optique, Universite de Reims, BP 1039, 51687 Reims Cedex 2 (France)]. E-mail: guofuan@yahoo.com; JI, Y.L. [Suzhou Institute for Nonferrous Metals Processing Technology, No. 200 Shenxu Road, Suzhou Industrial Park, Suzhou 215021 (China); Trannoy, N. [Unite de Thermique et d' Analyse Physique, Laboratoire d' Energetique et d' Optique, Universite de Reims, BP 1039, 51687 Reims Cedex 2 (France); Lu, J. [LASMIS, Universite de Technologie de Troyes, 12 Rue Marie Curie, Troyes 10010 (France)

2006-06-15

Scanning thermal microscopy (SThM) was used to map thermal conductivity images in an ultrafine-grained copper surface layer produced by surface mechanical attrition treatment (SMAT). It is found that the deformed surface layer shows different thermal conductivities that strongly depend on the grain size of the microstructure: the thermal conductivity of the nanostructured surface layer decreases obviously when compared with that of the coarse-grained matrix of the sample. The role of the grain boundaries in thermal conduction is analyzed in correlation with the heat conduction mechanism in pure metal. A theoretical approach, based on this investigation, was used to calculate the heat flow from the probe tip to the sample and then estimate the thermal conductivities at different scanning positions. Experimental results and theoretical calculation demonstrate that SThM can be used as a tool for the thermal property and microstructural analysis of ultrafine-grained microstructures.

Hydrogen and deuterium permeation in copper alloys, copper--gold brazing alloys, gold, and the in situ growth of stable oxide permeation barriers

International Nuclear Information System (INIS)

Begeal, D.R.

1978-01-01

The deuterium permeation through several copper alloys has been measured over a temperature range of 550 to 830 K using the membrane technique. In some cases, the hydrogen permeability was also measured. The results were divided into three categories: common alloys, gold alloys, and stable oxide forming alloys. Common alloys which showed typical bulk metallic diffusion with litle change in the permeation activation energy as compared to copper (77 kJ/mol for D 2 ) were: (additions are in weight percent) 5% Sn, 2.3% U, 0.15% Zr, 4% Sn+4% Pb+4% Zn, 3% Si, and 7% Al+2% Fe. Compared to copper, the D 2 permeability at 573 K was reduced by factors of 2.0, 2.7, 4.5, 5.3, 5.9, and 7.0, respectively. A series of gold--copper alloys including pure gold, 80% Au, 50% Au, 49% Au, and 35% Au also showed typical bulk metallic diffusion with a trend of decreasing permeability (increasing activation energies for permeation) with increasing gold content. There were also pronounced inflections or shifts in the permeability at approx.370 0 C, or about the order--disorder transition for Cu 3 Au and CuAu, for the 80% and 50% alloys. Two alloys did not exhibit bulk metallic permeation behavior and the permeabiltiy was in fact controlled by surface oxide layers. It was found that a layer of beryllium oxide could be formed on Cu+2% Be and a layer of aluminum oxide could be formed on Cu+7% Al+2% Si. As compared to 0.25 mm-thick copper, the deuterium permeability at 500 0 C was reduced by a factor of approx.250 for Cu--Be and approx.1000 for Cu--Al--Si. The activation energies for deuterium permeation were 98 kJ/mol and 132 kJ/mol, respectively. The mechanism for the oxide growth is the high-temperature hydrogen reduction of nearby less stable oxides, simultaneous with oxidation of the active metal, Be or Al, by trace amounts of water in the hydrogen. Ion microprobe mass analysis identified the oxide layers as containing beryllium or aluminum but not containing copper

The evaluation of zinc and copper content in tooth enamel without any pathological changes - an in vitro study.

Science.gov (United States)

Klimuszko, Elzbieta; Orywal, Karolina; Sierpinska, Teresa; Sidun, Jarosław; Golebiewska, Maria

2018-01-01

The objectives of the study were to evaluate the content of copper and zinc in individual layers of tooth enamel and to analyze the relationships between the study minerals in individual layers of tooth enamel. Fifteen human permanent teeth were cut off every 150 μm alongside the labial surface. Acid biopsy of each layer was performed. The zinc content was determined using the air-acetylene flame method. The copper content was determined using the electrothermal technique with argon. The mean zinc concentrations increased significantly starting from the outer enamel surface, with the maximum concentration in the 150-300 μm layer. The mean copper concentrations increased substantially from the outer enamel surface to a depth of 150 μm, and then a slight downward trend of this mineral levels was seen, down to a depth of 450 μm. Strong positive correlation was found between the zinc and copper concentrations at depths of 150-300, 450-600 and 600-750 μm. The levels of zinc and copper in the outer enamel layers may have an effect on the increased content of unipolar minerals at deeper enamel layers. The content of the study elements determined may reflect the process of mineralization and maturation of enamel in the pre-eruption period.

Inspection of power and ground layers in PCB images

Science.gov (United States)

Bunyak, Filiz; Ercal, Fikret

1998-10-01

In this work, we present an inspection method for power and ground (P&G) layers of printed circuit boards (PCB) also called utility layers. Design considerations for the P&G layers are different than those of signal layers. Current PCB inspection approaches cannot be applied to these layers. P&G layers act as internal ground, neutral or power sources. P&G layers are predominantly copper with occasional pad areas (without copper) called clearance. Defect definition is based on the spacing between the holes that will be drilled in clearances and the surrounding copper. Overlap of pads of different sizes and shapes are allowed. This results in complex, hard to inspect clearances. Our inspection is based on identification of shape, size and position of the individual pads that contribute to an overlapping clearance and then inspection of each pad based on design rules and tolerances. Main steps of our algorithm are as follows: (1) extraction and preprocessing of clearance contours; (2) decomposition of contours into segments: corner detection and matching lines or circular arcs between two corners; (3) determination of the pads from partial contour information obtained in step (2), and (4) design rules checking for each detected pad.

Polypyrrole electrodeposited on copper from an aqueous phosphate solution: Corrosion protection properties

OpenAIRE

Redondo, Clara; Breslin, Carmel B.

2007-01-01

Highly adherent and homogenous polypyrrole films were electrodeposited at copper from a dihydrogen phosphate solution. The polypyrrole films were electrosynthesized in the overoxidized state by cycling the copper electrode from –0.4 to 1.8 V (SCE) in a pyrrole-containing phosphate solution. The growth of the polypyrrole films was facilitated by the initial oxidation of the copper electrode in the phosphate solution to generate a mixed copper–phosphate, copper oxide or hydroxide layer. This la...

Boiling heat transfer on single phosphor bronze and copper mesh microstructures

Directory of Open Access Journals (Sweden)

Orman Łukasz J.

2014-03-01

Full Text Available The paper presents experimental results of boiling heat transfer of distilled water and ethyl alcohol on surfaces covered with single layers of wire mesh structures made of phosphor bronze and copper. For each material two kinds of structures have been considered (higher and lower in order to determine the impact of the height of the structure on boiling heat transfer. The wire diameter of the copper meshes was 0,25 mm and 0,32 mm, while of the bronze meshes: 0,20 mm and 0,25 mm. The structures had the same mesh aperture (distance between the wires – 0,50 mm for copper and 0,40 for bronze but different wire diameter and, consequently, different height of the layers. The tests have been performed under ambient pressure in the pool boiling mode. The obtained results indicate a visible impact of the layer height on the boiling heat transfer performance of the analysed microstructures.

Adsorption of 2-mercaptobenzothiazole on copper surface from phosphate solutions

International Nuclear Information System (INIS)

Kazansky, L.P.; Selyaninov, I.A.; Kuznetsov, Yu.I.

2012-01-01

Analysis of the electrochemical and XPS results has shown that adsorption of 2-mercaptobenzothiazole (MBT) on copper electrodes in neutral phosphate solutions proceeds through the formation of the chemical bonds by copper (I) cations with exo-sulfur and nitrogen atoms. A protection layer formed of Cu(I)MBT complex prevents precipitation of copper (II) phosphate on a copper surface. The thickness of the surface film consisting of a complex [Cu(I)MBT] n (having probably polymeric nature), where MBT acts as at least three-dentate ligand, increases depending on the exposure time, reaching 8-9 nm after immersing for 12 h in test solution. Even in a case of the preliminary formation of copper (II) phosphate on the copper electrode at the anodic potential addition of small amounts of MBT results in complete removal of copper (II) phosphate from the surface.

Fabrication of free-standing copper foils covered with highly-ordered copper nanowire arrays

Science.gov (United States)

Zaraska, Leszek; Sulka, Grzegorz D.; Jaskuła, Marian

2012-07-01

The through-hole nanoporous anodic aluminum oxide (AAO) membranes with relatively large surface area (ca. 2 cm2) were employed for fabrication of free-standing and mechanically stable copper foils covered with close-packed and highly-ordered copper nanowire arrays. The home-made AAO membranes with different pore diameters and interpore distances were fabricated via a two-step self-organized anodization of aluminum performed in sulfuric acid, oxalic acid and phosphoric acid followed by the pore opening/widening procedure. The direct current (DC) electrodeposition of copper was performed efficiently on both sides of AAO templates. The bottom side of the AAO templates was not insulated and consequently Cu nanowire arrays on thick Cu layers were obtained. The proposed template-assisted fabrication of free-standing copper nanowire array electrodes is a promising method for synthesis of nanostructured current collectors. The composition of Cu nanowires was confirmed by energy dispersive X-Ray spectroscopy (EDS) and X-ray diffraction (XRD) analyses. The structural features of nanowires were evaluated from field emission scanning electron microscopy (FE-SEM) images and compared with the characteristic parameters of anodic alumina membranes.

Fabrication of free-standing copper foils covered with highly-ordered copper nanowire arrays

International Nuclear Information System (INIS)

Zaraska, Leszek; Sulka, Grzegorz D.; Jaskuła, Marian

2012-01-01

The through-hole nanoporous anodic aluminum oxide (AAO) membranes with relatively large surface area (ca. 2 cm 2 ) were employed for fabrication of free-standing and mechanically stable copper foils covered with close-packed and highly-ordered copper nanowire arrays. The home-made AAO membranes with different pore diameters and interpore distances were fabricated via a two-step self-organized anodization of aluminum performed in sulfuric acid, oxalic acid and phosphoric acid followed by the pore opening/widening procedure. The direct current (DC) electrodeposition of copper was performed efficiently on both sides of AAO templates. The bottom side of the AAO templates was not insulated and consequently Cu nanowire arrays on thick Cu layers were obtained. The proposed template-assisted fabrication of free-standing copper nanowire array electrodes is a promising method for synthesis of nanostructured current collectors. The composition of Cu nanowires was confirmed by energy dispersive X-Ray spectroscopy (EDS) and X-ray diffraction (XRD) analyses. The structural features of nanowires were evaluated from field emission scanning electron microscopy (FE-SEM) images and compared with the characteristic parameters of anodic alumina membranes.

Silver and copper nanoclusters in the lustre decoration of Italian Renaissance pottery: an EXAFS study

Science.gov (United States)

Padovani, S.; Borgia, I.; Brunetti, B.; Sgamellotti, A.; Giulivi, A.; D'Acapito, F.; Mazzoldi, P.; Sada, C.; Battaglin, G.

Lustre is one of the most important decorative techniques of the Medieval and Renaissance pottery of the Mediterranean basin, capable of producing brilliant metallic reflections and iridescence. Following the recent finding that the colour of lustre decorations is mainly determined by copper and silver nanoclusters dispersed in the glaze layer, the local environment of copper and silver atoms has been studied by extended X-ray absorption fine structure (EXAFS) spectroscopy on original samples of gold and red lustre. It has been found that, in gold lustre, whose colour is attributed mainly to the silver nanocluster dispersion, silver is only partially present in the metallic form and copper is almost completely oxidised. In the red lustre, whose colour is attributed mainly to the copper nanocluster dispersion, only a fraction of copper is present in the metallic form. EXAFS measurements on red lustre, carried out in the total electron yield mode to probe only the first 150 nm of the glaze layer, indicated that in some cases lustre nanoclusters may be confined in a very thin layer close to the surface.

Direct electroplating of copper on tantalum from ionic liquids in high vacuum: origin of the tantalum oxide layer.

Science.gov (United States)

Schaltin, Stijn; D'Urzo, Lucia; Zhao, Qiang; Vantomme, André; Plank, Harald; Kothleitner, Gerald; Gspan, Christian; Binnemans, Koen; Fransaer, Jan

2012-10-21

In this paper, it is shown that high vacuum conditions are not sufficient to completely remove water and oxygen from the ionic liquid 1-ethyl-3-methylimidazolium chloride. Complete removal of water demands heating above 150 °C under reduced pressure, as proven by Nuclear Reaction Analysis (NRA). Dissolved oxygen gas can only be removed by the use of an oxygen scavenger such as hydroquinone, despite the fact that calculations show that oxygen should be removed completely by the applied vacuum conditions. After applying a strict drying procedure and scavenging of molecular oxygen, it was possible to deposit copper directly on tantalum without the presence of an intervening oxide layer.

Analysis of Historic Copper Patinas. Influence of Inclusions on Patina Uniformity

Directory of Open Access Journals (Sweden)

Tingru Chang

2017-03-01

Full Text Available The morphology and elemental composition of cross sections of eight historic copper materials have been explored. The materials were taken from copper roofs installed in different middle and northern European environments from the 16th to the 19th century. All copper substrates contain inclusions of varying size, number and composition, reflecting different copper ores and production methods. The largest inclusions have a size of up to 40 μm, with most inclusions in the size ranging between 2 and 10 μm. The most common element in the inclusions is O, followed by Pb, Sb and As. Minor elements include Ni, Sn and Fe. All historic patinas exhibit quite fragmentized bilayer structures, with a thin inner layer of cuprite (Cu2O and a thicker outer one consisting mainly of brochantite (Cu4SO4(OH6. The extent of patina fragmentation seems to depend on the size of the inclusions, rather than on their number and elemental composition. The larger inclusions are electrochemically nobler than the surrounding copper matrix. This creates micro-galvanic effects resulting both in a profound influence on the homogeneity and morphology of historic copper patinas and in a significantly increased ratio of the thicknesses of the brochantite and cuprite layers. The results suggest that copper patinas formed during different centuries exhibit variations in uniformity and corrosion protection ability.

Field Effect Transistors Using Atomically Thin Layers of Copper Indium Selenide (CuInSe)

Science.gov (United States)

Patil, Prasanna; Ghosh, Sujoy; Wasala, Milinda; Lei, Sidong; Vajtai, Robert; Ajayan, Pulickel; Talapatra, Saikat

We will report fabrication of field-effect transistors (FETs) using few-layers of Copper Indium Selenide (CuInSe) flakes exfoliated from crystals grown using chemical vapor transport technique. Our transport measurements indicate n-type FET with electron mobility µ ~ 3 cm2 V-1 s-1 at room temperature when Silicon dioxide (SiO2) is used as a back gate. Mobility can be further increased significantly when ionic liquid 1-Butyl-3-methylimidazolium hexafluorophosphate (BMIM-PF6) is used as top gate. Similarly subthreshold swing can be further improved from 103 V/dec to 0.55 V/dec by using ionic liquid as a top gate. We also found ON/OFF ratio of ~ 102 for both top and back gate. Comparison between ionic liquid top gate and SiO2 back gate will be presented and discussed. This work is supported by the U.S. Army Research Office through a MURI Grant # W911NF-11-1-0362.

Crystallization of copper metaphosphate glass

Science.gov (United States)

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.

Analysis of a beryllium-copper diffusion joint after HHF test

International Nuclear Information System (INIS)

Guiniatouline, R.N.; Mazul, I.V.; Gorodetsky, A.E.; Zalavutdinov, R.Kh.; Rybakov, S.Yu.; Savenko, V.I.

1996-01-01

The development of beryllium-copper joints which can withstand relevant ITER divertor conditions is one of the important tasks at the present time. One of the main problems associated with these joints is the intermetallic layers. The strength and life of these joints significantly depend on 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 a beryllium-copper mock-up. The HHF test was performed on the e-beam facility (EBTS, SNLA). The following methods were used for analysis: roentgenographic analysis, X-ray spectrum analysis and fracture analysis. During the investigation the following studies were undertaken: the analysis of the diffusion boundary layer, which was obtained at the cross-section of one of the tiles, the analysis of the debonded surfaces of several beryllium tiles and corresponding copper parts and the analysis of the upper surface of one of the tiles after HHF tests. The joint roentgenographic and element analyses revealed the following phases in the diffusion zone: Cu 2 Be (∝170 μm), CuBe (∝30 μm), CuBe 2 (∝1 μm) and a solid solution of copper in beryllium. The phases Cu 2 Be, CuBe and the solid solution of copper in beryllium were detected by the quantitative microanalysis and the phases CuBe, CuBe 2 and CuBe, by the roentgenographic analysis. The fracture (origin) is located in the central part of the tiles. This crack was caused by residual stresses and thermal fatigue testing. This analysis provides important data on the joint quality and may be used for all types of joints used for ITER applications. (orig.)

Facet-dependent study of efficient growth of graphene on copper

Indian Academy of Sciences (India)

The growth of graphene by chemical vapour deposition (CVD) on copper is the most promising scalable method for high-quality graphene. The use of ethanol, an economic and safe precursor, for the fast growth of graphene on copper by a home-built CVD set-up was analysed. Full coverage of uniform single-layer ...

Characterization of nanocrystalline products prepared by mechanochemical reduction of copper sulphide

DEFF Research Database (Denmark)

Balaz, P.; Godocikova, E.; Boldizarova, E.

2002-01-01

The mechanochemical processing of the copper sulphide with iron in a high-energy mill was studied. The nanosized copper of 10 nm crystallite size and the hexagonal pyrrhotite 1C were identified among products of the reaction by methods of XRD and Mossbauer spectroscopy. In the surface layer...

[XPS analysis of beads formed by fuse breaking of electric copper wire].

Science.gov (United States)

Wu, Ying; Meng, Qing-Shan; Wang, Xin-Ming; Gao, Wei; Di, Man

2010-05-01

The in-depth composition of beads formed by fuse breaking of the electric copper wire in different circumstances was studied by XPS with Ar+ ion sputtering. In addition, the measured Auger spectra and the calculated Auger parameters were compared for differentiation of the substances of Cu and Cu2O. Corresponding to the sputtering depth, the molten product on a bead induced directly by fuse breaking of the copper wire without cover may be distinguished as three portions: surface layer with a drastic decrease in carbon content; intermediate layer with a gentle change in oxygen content and gradually diminished carbon peak, and consisting of Cu2O; transition layer without Cu2O and with a rapid decrease in oxygen content. While the molten product on a bead formed by fuse breaking of the copper wire after its insulating cover had been burned out may be distinguished as two portions: surface layer with carbon content decreasing quickly; subsurface layer without Cu2O and with carbon and oxygen content decreasing gradually. Thus, it can be seen that there was an obvious interface between the layered surface product and the substrate for the first type of bead, while as to the second type of bead there was no interface. As a result, the presence of Cu2O and the quantitative results can be used to identify the molten product on a bead induced directly by fuse breaking of the copper wire without cover and the molten product on a bead formed by fuse breaking of the cupper wire after its insulating cover had been burned out, as a complementary technique for the judgments of fire cause.

The Impedance of Multi-layer Vacuum Chambers

CERN Document Server

Vos, L

2003-01-01

Many components of the LHC vacuum chamber have multi-layered walls : the copper coated cold beam screen, the titanium coated ceramic chamber of the dump kickers, the ceramic chamber of the injection kickers coated with copper stripes, only to name a few. Theories and computer programs are available for some time already to evaluate the impedance of these elements. Nevertheless, the algorithm developed in this paper is more convenient in its application and has been used extensively in the design phase of multi-layer LHC vacuum chamber elements. It is based on classical transmission line theory. Closed expressions are derived for simple layer configurations, while beam pipes involving many layers demand a chain calculation. The algorithm has been tested with a number of published examples and was verified with experimental data as well.

Optically detected X-ray absorption spectroscopy measurements as a means of monitoring corrosion layers on copper.

Science.gov (United States)

Dowsett, Mark G; Adriaens, Annemie; Jones, Gareth K C; Poolton, Nigel; Fiddy, Steven; Nikitenko, Sergé

2008-11-15

XANES and EXAFS information is conventionally measured in transmission through the energy-dependent absorption of X-rays or by observing X-ray fluorescence, but secondary fluorescence processes, such as the emission of electrons and optical photons (e.g., 200-1000 nm), can also be used as a carrier of the XAS signatures, providing complementary information such as improved surface specificity. Where the near-visible photons have a shorter range in a material, the data will be more surface specific. Moreover, optical radiation may escape more readily than X-rays through liquid in an environmental cell. Here, we describe a first test of optically detected X-ray absorption spectroscopy (ODXAS) for monitoring electrochemical treatments on copper-based alloys, for example, heritage metals. Artificially made corrosion products deposited on a copper substrate were analyzed in air and in a 1% (w/v) sodium sesquicarbonate solution to simulate typical conservation methods for copper-based objects recovered from marine environments. The measurements were made on stations 7.1 and 9.2 MF (SRS Daresbury, UK) using the mobile luminescence end station (MoLES), supplemented by XAS measurements taken on DUBBLE (BM26 A) at the ESRF. The ODXAS spectra usually contain fine structure similar to that of XAS spectra measured in X-ray fluorescence. Importantly, for the compounds examined, the ODXAS is significantly more surface specific, and >98% characteristic of thin surface layers of 0.5-1.5-microm thickness in cases where X-ray measurements are dominated by the substrate. However, EXAFS and XANES from broadband optical measurements are superimposed on a high background due to other optical emission modes. This produces statistical fluctuations up to double what would be expected from normal counting statistics because the data retain the absolute statistical fluctuation in the original raw count, while losing up to 70% of their magnitude when background is removed. The problem may be

Protection of copper surface with phytic acid against corrosion in chloride solution.

Science.gov (United States)

Peca, Dunja; Pihlar, Boris; Ingrid, Milošev

2014-01-01

Phytic acid (inositol hexaphosphate) was tested as a corrosion inhibitor for copper in 3% sodium chloride. Phytic acid is a natural compound derived from plants, it is not toxic and can be considered as a green inhibitor. Electrochemical methods of linear polarization and potentiodynamic polarization were used to study the electrochemical behaviour and evaluate the inhibition effectiveness. To obtain the optimal corrosion protection the following experimental conditions were investigated: effect of surface pre-treatment (abrasion and three procedures of surface roughening), pre-formation of the layer of phytic acid, time of immersion and concentration of phytic acid. To evaluate the surface pre-treatment procedures the surface roughness and contact angle were measured. Optimal conditions for formation of phytic layer were selected resulting in the inhibition effectiveness of nearly 80%. Morphology and composition of the layer were further studied by scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. The layer of phytic acid with thickness in the nanometer range homogeneously covers the copper surface. The obtained results show that this natural compound can be used as a mildly effective corrosion inhibitor for copper in chloride solution.

Effect of Cow Urine on the Growth Characteristics of Fusarium lateritium, an Important Coffee Fungus in Zimbabwe

Directory of Open Access Journals (Sweden)

Timothy Gotora

2014-01-01

Full Text Available An in vitro assay was carried out to establish if cow urine at different concentrations (500 µL/mL, 300 µL/mL, 200 µL/mL, and 100 µL/mL can be used to control the growth of F. lateritium, the fungal agent causing Fusarium bark disease in coffee. The growth characteristics selected were conidial germination, germ tube length, mycelial growth rate, and sporulation. Copper oxychloride 50% W.P. was the standard, distilled water was the negative control, and undiluted cow urine was the positive control. The undiluted cow urine was most effective in inhibiting fungal growth with the rest of the cow urine concentrations showing dose dependent efficacy compared to the negative control (P < 0.01. Copper oxychloride had the highest efficacy of all treatments with the exception of the inhibition of mycelial growth where undiluted cow urine had higher efficacy and sporulation where efficacy was comparable to undiluted cow urine. There is potential for the use of cow urine as a means of controlling Fusarium bark disease with other advantages being availability, low cost, and limited environmental damage.

Copper diffusion in TaN-based thin layers

Energy Technology Data Exchange (ETDEWEB)

Nazon, J. [Universite Montpellier II, Institut Charles Gerhardt, UMR 5253 CNRS-UM2-ENSCM-UM1, cc 1504, 34095 Montpellier Cedex 5 (France); Fraisse, B. [Laboratoire Structure, Proprietes et Modelisation des Solides (UMR 8580), Ecole Centrale de Paris, Grande Voie des Vignes, 92295 Chatenay-Malabry Cedex (France); Sarradin, J. [Universite Montpellier II, Institut Charles Gerhardt, UMR 5253 CNRS-UM2-ENSCM-UM1, cc 1504, 34095 Montpellier Cedex 5 (France); Fries, S.G. [SGF Scientific Consultancy, Arndt str.9, D-52064 Aachen (Germany); Tedenac, J.C. [Universite Montpellier II, Institut Charles Gerhardt, UMR 5253 CNRS-UM2-ENSCM-UM1, cc 1504, 34095 Montpellier Cedex 5 (France); Frety, N. [Universite Montpellier II, Institut Charles Gerhardt, UMR 5253 CNRS-UM2-ENSCM-UM1, cc 1504, 34095 Montpellier Cedex 5 (France)], E-mail: Nicole.Frety@univ-montp2.fr

2008-07-15

The diffusion of Cu through TaN-based thin layers into a Si substrate has been studied. The barrier efficiency of TaN/Ta/TaN multilayers of 150 nm in thickness has been investigated and is compared with that of TaN single layers. Thermal stabilities of these TaN-based thin layers against Cu diffusion were determined from in situ X-ray diffraction experiments, conducted in the temperature range of 773-973 K. The TaN/Ta/TaN barrier appeared to be more efficient in preventing Cu diffusion than the TaN single layer.

Effect of ion irradiation on the optical properties and room temperature oxidation of copper surface

Energy Technology Data Exchange (ETDEWEB)

Poperenko, L.V.; Ramadan Shaaban, Essam; Khanh, N.Q.; Stashchuk, V.S.; Vinnichenko, M.V.; Yurgelevich, I.V.; Nosach, D.V.; Lohner, T

2004-05-01

Ex situ and in situ spectroellipsometric investigation of room temperature oxidation of ion-implanted copper surface was performed. The ellipsometer is capable to measure simultaneously the ellipsometric parameters {psi} and {delta} at 88 different wavelength values in the range of 280-760 nm within a few minutes in the high precision operation mode using two zone averaging and within a fraction of a second in the one zone operation mode. The native oxide layer formed earlier on the surface of the copper was sputtered off during the aluminum ion implantation. In situ study of the growth of the newly formed native oxide layer on the ion implanted surface was carried out. Ion beam analytical measurements were performed to gain further information on the native oxide layer. The absolute number of the oxygen atoms in the native copper oxide layer was determined. The depth distribution of the implanted aluminum was extracted from Rutherford backscattering spectra. It is found that Al implantation enhanced the oxidation resistance.

Effect of ion irradiation on the optical properties and room temperature oxidation of copper surface

International Nuclear Information System (INIS)

Poperenko, L.V.; Ramadan Shaaban, Essam; Khanh, N.Q.; Stashchuk, V.S.; Vinnichenko, M.V.; Yurgelevich, I.V.; Nosach, D.V.; Lohner, T.

2004-01-01

Ex situ and in situ spectroellipsometric investigation of room temperature oxidation of ion-implanted copper surface was performed. The ellipsometer is capable to measure simultaneously the ellipsometric parameters Ψ and Δ at 88 different wavelength values in the range of 280-760 nm within a few minutes in the high precision operation mode using two zone averaging and within a fraction of a second in the one zone operation mode. The native oxide layer formed earlier on the surface of the copper was sputtered off during the aluminum ion implantation. In situ study of the growth of the newly formed native oxide layer on the ion implanted surface was carried out. Ion beam analytical measurements were performed to gain further information on the native oxide layer. The absolute number of the oxygen atoms in the native copper oxide layer was determined. The depth distribution of the implanted aluminum was extracted from Rutherford backscattering spectra. It is found that Al implantation enhanced the oxidation resistance

Layer-selective synthesis of bilayer graphene via chemical vapor deposition

Science.gov (United States)

Yang, Ning; Choi, Kyoungjun; Robertson, John; Park, Hyung Gyu

2017-09-01

A controlled synthesis of high-quality AB-stacked bilayer graphene by chemical vapor deposition demands a detailed understanding of the mechanism and kinetics. By decoupling the growth of the two layers via a growth-and-regrowth scheme, we report the kinetics and termination mechanisms of the bilayer graphene growth on copper. We observe, for the first time, that the secondary layer growth follows Gompertzian kinetics. Our observations affirm the postulate of a time-variant transition from a mass-transport-limited to a reaction-limited regimes and identify the mechanistic disparity between the monolayer growth and the secondary-layer expansion underneath the monolayer cover. It is the continuous carbon supply that drives the expansion of the graphene secondary layer, rather than the initially captured carbon amount, suggesting an essential role of the surface diffusion of reactant adsorbates in the interspace between the top graphene layer and the underneath copper surface. We anticipate that the layer selectivity of the growth relies on the entrance energetics of the adsorbed reactants to the graphene-copper interspace across the primary-layer edge, which could be engineered by tailoring the edge termination state. The temperature-reliant saturation area of the secondary-layer expansion is understood as a result of competitive attachment of carbon and hydrogen adatoms to the secondary-layer graphene edge.

Optimization of copper electroplating process applied for microfabrication on flexible polyethylene terephthalate substrate

International Nuclear Information System (INIS)

Le, Nguyen Ngan; Hue Phan, Thi Cam; Le, Anh Duy; Dung Dang, Thi My; Dang, Mau Chien

2015-01-01

Electroplating is an important step in microfabrication in order to increase thickness of undersized parts up to a few micrometers with a low-cost, fast method that is easy to carry out, especially for metals such as copper, nickel, and silver. This important step promotes the development of the fabrication technology of electronic devices on a flexible substrate, also known as flexible electronic devices. Nevertheless, this technology has some disadvantages such as low surface uniformity and high resistivity. In this paper, parameters of copper electroplating were studied, such as the ratio of copper (II) sulfate (CuSO_4) concentration to sulfuric acid (H_2SO_4) concentration and electroplating current density, in order to obtain low resistivity and high surface uniformity of the copper layer. Samples were characterized by scanning electron microscopy (SEM), four-point probe, and surface profiler. The results showed that the sample resistivity could be controlled from about 2.0 to about 3.5 μΩ · cm, and the lowest obtained resistivity was 1.899 μΩ · cm. In addition, surface uniformity of the electroplated copper layer was also acceptable. The thickness of the copper layer was about 10 μm with an error of about 0.5 μm. The most suitable conditions for the electroplating process were CuSO_4 concentration of 0.4 mol l"−"1, H_2SO_4 concentration of 1.0 mol l"−"1, and low electroplating current density of 10–20 mA cm"−"2. All experiments were performed on a flexible polyethylene terephthalate (PET) substrate. (paper)

The role of oxide structure on copper wire to the rubber adhesion

Science.gov (United States)

Su, Yea-Yang; Shemenski, Robert M.

2000-07-01

Most metals have an oxide layer on the surface. However, the structure of the oxide varies with the matrix composition, and depends upon the environmental conditions. A bronze coating, nominal composition of 98.5% Cu and balance of Sn, is applied to steel wire for reinforcing pneumatic tire beads and to provide adhesion to rubber. This work studied the influence of copper oxides on the bronze coating on adhesion during vulcanization. To emphasize the oxide structures, electrolytic tough pitch (ETP) copper wire was used instead of the traditional bronze-coated tire bead wire. Experimental results confirmed the hypothesis that cuprous oxide (Cu 2O) could significantly improve bonding between copper wire and rubber, and demonstrated that the interaction between rubber and oxide layer on wire is an electrochemical reaction.

Optimization of chemical displacement deposition of copper on porous silicon.

Science.gov (United States)

Bandarenka, Hanna; Redko, Sergey; Nenzi, Paolo; Balucani, Marco; Bondarenko, Vitaly

2012-11-01

Copper (II) sulfate was used as a source of copper to achieve uniform distribution of Cu particles deposited on porous silicon. Layers of the porous silicon were formed by electrochemical anodization of Si wafers in a mixture of HF, C3H7OH and deionized water. The well-known chemical displacement technique was modified to grow the copper particles of specific sizes. SEM and XRD analysis revealed that the outer surface of the porous silicon was covered with copper particles of the crystal orientation inherited from the planes of porous silicon skeleton. The copper crystals were found to have the cubic face centering elementary cell. In addition, the traces of Cu2O cubic primitive crystalline phases were identified. The dimensions of Cu particles were determined by the Feret's analysis of the SEM images. The sizes of the particles varied widely from a few to hundreds of nanometers. A phenomenological model of copper deposition was proposed.

PROMETHEE II: A knowledge-driven method for copper exploration

Science.gov (United States)

Abedi, Maysam; Ali Torabi, S.; Norouzi, Gholam-Hossain; Hamzeh, Mohammad; Elyasi, Gholam-Reza

2012-09-01

This paper describes the application of a well-known Multi Criteria Decision Making (MCDM) technique called Preference Ranking Organization METHod for Enrichment Evaluation (PROMETHEE II) to explore porphyry copper deposits. Various raster-based evidential layers involving geological, geophysical, and geochemical geo-datasets are integrated to prepare a mineral prospectivity mapping (MPM). In a case study, thirteen layers of the Now Chun copper deposit located in the Kerman province of Iran are used to explore the region of interest. The PROMETHEE II technique is applied to produce the desired MPM, and the outputs are validated using twenty-one boreholes that have been classified into five classes. This proposed method shows a high performance when providing the MPM while reducing the cost of exploratory drilling in the study area.

Diffuse emission and control of copper in urban surface runoff.

Science.gov (United States)

Boller, M A; Steiner, M

2002-01-01

Copper washed off from roofs and roads is considered to be a major contribution to diffuse copper pollution of urban environments. In order to guarantee sustainable protection of soils and water, the long-term strategy is to avoid or replace copper containing materials on roofs and fagades. Until achievement of this goal, a special adsorber system is suggested to control the diffuse copper fluxes by retention of copper by a mixture of granulated iron-hydroxide (GEH) and calcium carbonate. Since future stormwater runoff concepts are based on decentralised runoff infiltration into the underground, solutions are proposed which provide for copper retention in infiltration sites using GEH adsorption layers. The example of a large copper façade of which the runoff is treated in an adsorption trench reveals the first full-scale data on façade runoff and adsorber performance. During the first year of investigation average façade runoff concentrations in the range of 1-10 mg Cu/l are reduced by 96-99% in the adsorption ditch.

Investigation of Electronic and Opto-Electronic Properties of Two-Dimensional (2D) Layers of Copper Indium Selenide Field Effect Transistors

Science.gov (United States)

Patil, Prasanna Dnyaneshwar

Investigations performed in order to understand the electronic and optoelectronic properties of field effect transistors based on few layers of 2D Copper Indium Selenide (CuIn7Se11) are reported. In general, field effect transistors (FETs), electric double layer field effect transistors (EDL-FETs), and photodetectors are crucial part of several electronics based applications such as tele-communication, bio-sensing, and opto-electronic industry. After the discovery of graphene, several 2D semiconductor materials like TMDs (MoS2, WS2, and MoSe2 etc.), group III-VI materials (InSe, GaSe, and SnS2 etc.) are being studied rigorously in order to develop them as components in next generation FETs. Traditionally, thin films of ternary system of Copper Indium Selenide have been extensively studied and used in optoelectronics industry as photoactive component in solar cells. Thus, it is expected that atomically thin 2D layered structure of Copper Indium Selenide can have optical properties that could potentially be more advantageous than its thin film counterpart and could find use for developing next generation nano devices with utility in opto/nano electronics. Field effect transistors were fabricated using few-layers of CuIn7Se11 flakes, which were mechanically exfoliated from bulk crystals grown using chemical vapor transport technique. Our FET transport characterization measurements indicate n-type behavior with electron field effect mobility microFE ≈ 36 cm2 V-1 s-1 at room temperature when Silicon dioxide (SiO2) is used as a back gate. We found that in such back gated field effect transistor an on/off ratio of 104 and a subthreshold swing ≈ 1 V/dec can be obtained. Our investigations further indicate that Electronic performance of these materials can be increased significantly when gated from top using an ionic liquid electrolyte [1-Butyl-3-methylimidazolium hexafluorophosphate (BMIM-PF6)]. We found that electron field effect mobility microFE can be increased from

Analysis of the electrolyte convection inside the concentration boundary layer during structured electrodeposition of copper in high magnetic gradient fields.

Science.gov (United States)

König, Jörg; Tschulik, Kristina; Büttner, Lars; Uhlemann, Margitta; Czarske, Jürgen

2013-03-19

To experimentally reveal the correlation between electrodeposited structure and electrolyte convection induced inside the concentration boundary layer, a highly inhomogeneous magnetic field, generated by a magnetized Fe-wire, has been applied to an electrochemical system. The influence of Lorentz and magnetic field gradient force to the local transport phenomena of copper ions has been studied using a novel two-component laser Doppler velocity profile sensor. With this sensor, the electrolyte convection within 500 μm of a horizontally aligned cathode is presented. The electrode-normal two-component velocity profiles below the electrodeposited structure show that electrolyte convection is induced and directed toward the rim of the Fe-wire. The measured deposited structure directly correlates to the observed boundary layer flow. As the local concentration of Cu(2+) ions is enhanced due to the induced convection, maximum deposit thicknesses can be found at the rim of the Fe-wire. Furthermore, a complex boundary layer flow structure was determined, indicating that electrolyte convection of second order is induced. Moreover, the Lorentz force-driven convection rapidly vanishes, while the electrolyte convection induced by the magnetic field gradient force is preserved much longer. The progress for research is the first direct experimental proof of the electrolyte convection inside the concentration boundary layer that correlates to the deposited structure and reveals that the magnetic field gradient force is responsible for the observed structuring effect.

Weight loss studies of fastener materials corrosion in contact with timbers treated with copper azole and alkaline copper quaternary compounds

Energy Technology Data Exchange (ETDEWEB)

Kear, Gareth [Building Research Association of New Zealand (BRANZ) Ltd., Science and Engineering Services, Private Bag 50 908, Porirua City 5240 (New Zealand)], E-mail: G.Kear@soton.ac.uk; Wu Haizhen; Jones, Mark S. [Building Research Association of New Zealand (BRANZ) Ltd., Science and Engineering Services, Private Bag 50 908, Porirua City 5240 (New Zealand)

2009-02-15

Corrosion rates of mild steel, AISI 316 stainless steel and hot-dipped galvanised steel in contact with preservative-treated Pinus radiata have been determined using four distinct accelerated (49 {+-} 1 deg. C) and non-accelerated (21 {+-} 2 deg. C) weight loss methodologies. The data were measured as a function of timber moisture content and copper concentration over periods of exposure ranging from 2 weeks to 14 months. The results show that the corrosion resistance of the stainless steel was not influenced by classification or magnitude of preservative loading. Corrosion rates of this material were multiple orders of magnitude lower than those of the mild and galvanised steels. In most instances, corrosion rates of hot-dipped galvanised layers in contact with alkaline copper quaternary-treated timbers were up to a factor of 10 times, or greater, than those measured for copper-chrome-arsenate treatments. A direct negative influence of copper ion concentration on the corrosion resistance of mild steel was also observed for each preservative type.

Role of copper oxides in contact killing of bacteria.

Science.gov (United States)

Hans, Michael; Erbe, Andreas; Mathews, Salima; Chen, Ying; Solioz, Marc; Mücklich, Frank

2013-12-31

The potential of metallic copper as an intrinsically antibacterial material is gaining increasing attention in the face of growing antibiotics resistance of bacteria. However, the mechanism of the so-called "contact killing" of bacteria by copper surfaces is poorly understood and requires further investigation. In particular, the influences of bacteria-metal interaction, media composition, and copper surface chemistry on contact killing are not fully understood. In this study, copper oxide formation on copper during standard antimicrobial testing was measured in situ by spectroscopic ellipsometry. In parallel, contact killing under these conditions was assessed with bacteria in phosphate buffered saline (PBS) or Tris-Cl. For comparison, defined Cu2O and CuO layers were thermally generated and characterized by grazing incidence X-ray diffraction. The antibacterial properties of these copper oxides were tested under the conditions used above. Finally, copper ion release was recorded for both buffer systems by inductively coupled plasma atomic absorption spectroscopy, and exposed copper samples were analyzed for topographical surface alterations. It was found that there was a fairly even growth of CuO under wet plating conditions, reaching 4-10 nm in 300 min, but no measurable Cu2O was formed during this time. CuO was found to significantly inhibit contact killing, compared to pure copper. In contrast, thermally generated Cu2O was essentially as effective in contact killing as pure copper. Copper ion release from the different surfaces roughly correlated with their antibacterial efficacy and was highest for pure copper, followed by Cu2O and CuO. Tris-Cl induced a 10-50-fold faster copper ion release compared to PBS. Since the Cu2O that primarily forms on copper under ambient conditions is as active in contact killing as pure copper, antimicrobial objects will retain their antimicrobial properties even after oxide formation.

Multi-polar resistance switching and memory effect in copper phthalocyanine junctions

International Nuclear Information System (INIS)

Qiao Shi-Zhu; Kang Shi-Shou; Li Qiang; Zhong Hai; Kang Yun; Yu Shu-Yun; Han Guang-Bing; Yan Shi-Shen; Mei Liang-Mo; Qin Yu-Feng

2014-01-01

Copper phthalocyanine junctions, fabricated by magnetron sputtering and evaporating methods, show multi-polar (unipolar and bipolar) resistance switching and the memory effect. The multi-polar resistance switching has not been observed simultaneously in one organic material before. With both electrodes being cobalt, the unipolar resistance switching is universal. The high resistance state is switched to the low resistance state when the bias reaches the set voltage. Generally, the set voltage increases with the thickness of copper phthalocyanine and decreases with increasing dwell time of bias. Moreover, the low resistance state could be switched to the high resistance state by absorbing the phonon energy. The stability of the low resistance state could be tuned by different electrodes. In Au/copper phthalocyanine/Co system, the low resistance state is far more stable, and the bipolar resistance switching is found. Temperature dependence of electrical transport measurements demonstrates that there are no obvious differences in the electrical transport mechanism before and after the resistance switching. They fit quite well with Mott variable range hopping theory. The effect of Al 2 O 3 on the resistance switching is excluded by control experiments. The holes trapping and detrapping in copper phthalocyanine layer are responsible for the resistance switching, and the interfacial effect between electrodes and copper phthalocyanine layer affects the memory effect. (interdisciplinary physics and related areas of science and technology)

Synthesis and characterization of αzirconium (IV) hydrogenphosphate containing metallic copper clusters

International Nuclear Information System (INIS)

Souza, Alexilda Oliveira de; Rangel, Maria do Carmo; Alves, Oswaldo Luiz

2005-01-01

The α-zirconium (IV) hydrogenphosphate (α-ZrP) has received great attention in the last years due to its properties like ion exchange, intercalation, ionic conductivity and catalytic activity. This work reports a method to produce metallic copper clusters on α-ZrP to be used as catalysts in petrochemical processes. It was found that the solids were non-crystalline regardless of the uptake of copper and the reduction. The specific surface area increased as a consequence of the increase of the interlayer distance to accept the copper ions between the layers. During the reduction, big clusters of copper (0,5-11μ) with different sizes and shapes were produced. (author)

He bubble sites in implanted copper alloy

International Nuclear Information System (INIS)

Moreno, D.; Eliezer, D.

1996-01-01

Structural materials in fusion reactors will be exposed to helium implantation over a broad range of energies. The deformation and partial exfoliation of surface layers due to hydrogen isotopes and helium contribute to the total erosion of the first wall. For this reason, one of the most important criteria in the choice of materials for the first wall of fusion reactors is the material's damage resistance. Recent advances in developing nuclear fusion reactors reveal that efficient heat removal from plasma-facing components is very important. Copper and copper alloys are considered an attractive choice for transporting such a high heat flux without thermal damage as they have high thermal conductivity. In the present study the authors report on the structural changes in a copper alloy, due to the helium implantation on the very near surface area, observed by transmission electron microscopy

Copper-coated laser-fusion targets using molecular-beam levitation

International Nuclear Information System (INIS)

Rocke, M.J.

1981-01-01

A series of diagnostic experiments at the Shiva laser fusion facility required targets of glass microspheres coated with 1.5 to 3.0 μm of copper. Previous batch coating efforts using vibration techniques gave poor results due to microsphere sticking and vacuum welding. Molecular Beam Levitation (MBL) represented a noncontact method to produce a sputtered copper coating on a single glassmicrosphere. The coating specifications that were achieved resulted in a copper layer up to 3 μm thick with the allowance of a maximum variation of 10 nm in surface finish and thickness. These techniques developed with the MBL may be applied to sputter coat many soft metals for fusion target applications

Electrometallurgy of copper refinery anode slimes

Science.gov (United States)

Scott, J. D.

1990-08-01

High-selenium copper refinery anode slimes form two separate and dynamically evolving series of compounds with increasing electrolysis time. In one, silver is progressively added to non-stoichiometric copper selenides, both those originally present in the anode and those formed subsequently in the slime layer, and in the other, silver-poor copper selenides undergo a dis-continuous crystallographic sequence of anodic-oxidative transformations. The silver-to-selenium molar ratio in the as-cast anode and the current density of electrorefining can be used to construct predominance diagrams for both series and, thus, to predict the final bulk “mineralogy” of the slimes. Although totally incorrect in detail, these bulk data are sufficiently accurate to provide explanations for several processing problems which have been experienced by Kidd Creek Division, Falconbridge Ltd., in its commercial tankhouse. They form the basis for a computer model which predicts final cathode quality from chemical analyses of smelter feed.

Effect of Physical Property and Surface Morphology of Copper Foil at Electrodeposition Parameter

Energy Technology Data Exchange (ETDEWEB)

Woo, Tae Gyu; Park, Il Song; Lee, Man Hyung; Seol, Kyeong Won [Chonbuk National University, Jeonju (Korea, Republic of)

2014-06-15

The effect of additives, current density and plated temperature on the surface morphology and physical property, during copper electrodeposition on polyimide (PI) film was investigated. Two kinds of additives, Cl and leveler (additive B), were used in this study. Electrochemical experiments were performed in conjunction with SEM, XRD and four-point probe to characterize the morphology and mechanical characteristics of copper electrodeposited in the presence of the additives. The surface roughness, crystal growth orientation and resistivity was controlled by the concentration of additive B. High resistivity and lower peel strength were observed on the surface of the copper layer electroplated in the electrolyte without additive B. However, a uniform surface, lower resistivity and high flexibility were obtained with a combination of 20 ppm Cl and 100 ppm additive B. Large particles were observed on the surface of the copper layer electroplated using a current density of 25 mA/cm{sup 2}, but a uniform surface and lower resistivity were obtained using a current density of 10 mA/cm{sup 2}. One of the required important properties of FCCL is flexibility of the copper foil. High flexibility of FCCL was obtained at a low current density, rather than a high current density. Moreover, a reasonable current density is 20 mA/cm{sup 2}, considering the productivity and mechanical properties of copper foil.

Copper Benzenetricarboxylate Metal-Organic Framework Nucleation Mechanisms on Metal Oxide Powders and Thin Films formed by Atomic Layer Deposition.

Science.gov (United States)

Lemaire, Paul C; Zhao, Junjie; Williams, Philip S; Walls, Howard J; Shepherd, Sarah D; Losego, Mark D; Peterson, Gregory W; Parsons, Gregory N

2016-04-13

Chemically functional microporous metal-organic framework (MOF) crystals are attractive for filtration and gas storage applications, and recent results show that they can be immobilized on high surface area substrates, such as fiber mats. However, fundamental knowledge is still lacking regarding initial key reaction steps in thin film MOF nucleation and growth. We find that thin inorganic nucleation layers formed by atomic layer deposition (ALD) can promote solvothermal growth of copper benzenetricarboxylate MOF (Cu-BTC) on various substrate surfaces. The nature of the ALD material affects the MOF nucleation time, crystal size and morphology, and the resulting MOF surface area per unit mass. To understand MOF nucleation mechanisms, we investigate detailed Cu-BTC MOF nucleation behavior on metal oxide powders and Al2O3, ZnO, and TiO2 layers formed by ALD on polypropylene substrates. Studying both combined and sequential MOF reactant exposure conditions, we find that during solvothermal synthesis ALD metal oxides can react with the MOF metal precursor to form double hydroxy salts that can further convert to Cu-BTC MOF. The acidic organic linker can also etch or react with the surface to form MOF from an oxide metal source, which can also function as a nucleation agent for Cu-BTC in the mixed solvothermal solution. We discuss the implications of these results for better controlled thin film MOF nucleation and growth.

Electrochemical performance of Sn-Sb-Cu film anodes prepared by layer-by-layer electrodeposition

International Nuclear Information System (INIS)

Jiang Qianlei; Xue Ruisheng; Jia Mengqiu

2012-01-01

A novel layer-by-layer electrodeposition and heat-treatment approach was attempted to obtain Sn-Sb-Cu film anode for lithium ion batteries. The preparation of Sn-Sb-Cu anodes started with galvanostatic electrochemically depositing antimony and tin sequentially on the substrate of copper foil collector. Sn-Sb and Cu-Sb alloys were formed when heated. The SEM analysis showed that the crystalline grains become bigger and the surface of the Sn-Sb-Cu anode becomes more denser after annealing. The energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) analysis showed the antimony, tin and copper were alloyed to form SnSb and Cu 2 Sb after heat treatment. The X-ray photoelectron spectroscopy (XPS) analysis showed the surface of the Sn-Sb-Cu electrode was covered by a thin oxide layer. Electrochemical measurements showed that the annealed Sn-Sb-Cu anode has high reversible capacity and good capacity retention. It exhibited a reversible capacity of about 962 mAh/g in the initial cycle, which still remained 715 mAh/g after 30 cycles.

Silane pre-treatments on copper and aluminium

International Nuclear Information System (INIS)

Deflorian, F.; Rossi, S.; Fedrizzi, L.

2006-01-01

A large part of aluminium products are coated with an organic layer in order to improve the corrosion resistance. Copper surfaces are also sometimes protected with an organic coating to improve the durability or the aesthetic properties. Examples of industrial applications are household appliances and heat exchanger components. For these applications it is not rare to have the industrial need to treat at the same time components made of aluminium and copper. In order to extend the service life of the organic coated copper a specific surface pre-treatment is often required. Nevertheless, probably because of the limited market of this application, no specific pre-treatments for copper are industrially developed, with the exception of cleaning procedures, but simply extensions of existing pre-treatments optimised for other metals (aluminium, zinc) are used. The application of silane pre-treatments as adhesion promoters for organic coated metals is remarkably increasing in the last decade, because silanes offer very good performance together with high environmental compatibility. The idea is therefore to try to develop a specific silane based pre-treatment for copper. The starting point is the existing silane products for aluminium, optimising the composition and the application conditions (concentration, temperature, pH of the bath, etc.) in order to develop a high performance copper alloy pre-treatment increasing the protective properties and the adhesion of a successively applied organic coating. Moreover these pre-treatments could be used for aluminium alloys too and therefore could be suggested for multi-metals components. The deposits were analysed using FTIR spectroscopy and optical and electron microscopic observations. A careful electrochemical characterisation, mainly by electrochemical impedance spectroscopy measurements (EIS) was carried out to highlight the presence of silane and to evaluate the performance of the different deposits. In order to study an

YCu(TeO32(NO3(H2O3: a novel layered tellurite

Directory of Open Access Journals (Sweden)

Stuart J. Mills

2016-08-01

Full Text Available A new hydrated yttrium copper tellurite nitrate, yttrium(III copper(II bis[trioxidotellurate(IV] nitrate trihydrate, has been synthesized hydrothermally in a Teflon-lined autoclave and structurally determined using synchrotron radiation. The new phase is the first example containing yttrium, copper and tellurium in one structure. Its crystal structure is unique, with relatively strongly bound layers extending parallel to (020, defined by YO8, CuO4 and TeO3 polyhedra, while the NO3− anions and one third of the water molecules lie between those layers. The structural unit consists of [Cu2(TeO34]4− loop-branched chains of {Cu...Te...Cu...Te} squares running parallel to [001], which are linked further into layers only through Y(O,H2O8 polyhedra. Weak `secondary' Te bonds and O—H...O hydrogen-bonding interactions, involving water molecules and layer O atoms, link the layers and interlayer species. IR spectroscopic data are also presented.

The role of the native oxide shell on the microwave sintering of copper metal powder compacts

International Nuclear Information System (INIS)

Mahmoud, Morsi M.; Link, Guido; Thumm, Manfred

2015-01-01

Highlights: • Thin oxide native layer had a critical role on microwave sintering of copper. • Explain why microwaves interact with copper powder differently than its bulk. • Abnormal expansion in copper is due to the plastic deformation and crack formation. • In-situ setup gives important insight about the microwave sintering of metals. • Microwave sintering is a promising candidate technology in powder metallurgy. - Abstract: Successful microwave sintering of several metal powders had been reported by many researchers with remarkable improvements in the materials properties and/or in the overall process. However, the concept behind microwave heating of metal powders has not been fully understood till now, as it is well known that bulk metals reflect microwaves. The progress of microwave sintering of copper metal powder compacts was investigated via combining both in-situ electrical resistivity and dilatometry measurements that give important information about microstructural changes with respect to the inter-particle electrical contacts during sintering. The sintering behavior of copper metal powders was depending on the type of the gas used, particle size, the initial green density, the soaking sintering time and the thin oxide layer on the particles surfaces. The thin copper oxide native layer (ceramics) that thermodynamically formed on the particles surfaces under normal handling and ambient environmental conditions had a very critical and important role in the microwave absorption and interaction, the sintering behavior and the microstructural changes. This finding could help to have a fundamental understanding of why MW’s interact with copper metal powder in a different way than its bulk at room temperature, i.e. why a given metal powder could be heated using microwaves while its bulk reflects it

Copper variation in Cu(In,Ga)Se{sub 2} solar cells with indium sulphide buffer layer

Energy Technology Data Exchange (ETDEWEB)

Spiering, S., E-mail: stefanie.spiering@zsw-bw.de [Zentrum für Sonnenenergie- und Wasserstoff-Forschung (ZSW) Baden-Wuerttemberg, Industriestrasse 6, 70565 Stuttgart (Germany); Paetel, S.; Kessler, F. [Zentrum für Sonnenenergie- und Wasserstoff-Forschung (ZSW) Baden-Wuerttemberg, Industriestrasse 6, 70565 Stuttgart (Germany); Igalson, M.; Abdel Maksoud, H. [Warsaw University of Technology (WUT), Faculty of Physics, Koszykowa 75, 00-662 Warszawa (Poland)

2015-05-01

In the manufacturing of Cu(In,Ga)Se{sub 2} (CIGS) thin film solar cells the application of a buffer layer on top of the absorber is essential to obtain high efficiency devices. Regarding the roll-to-roll production of CIGS cells and modules a vacuum deposition process for the buffer is preferable to the conventional cadmium sulphide buffer deposited in a chemical bath. Promising results have already been achieved for the deposition of indium sulphide buffer by different vacuum techniques. The solar device performance is very sensitive to the conditions at the absorber-buffer heterojunction. In view of optimization we investigated the influence of the Cu content in the absorber on the current-voltage characteristics. In this work the integral copper content was varied between 19 and 23 at.% in CIGS on glass substrates. An improvement of the cell performance by enhanced open circuit voltage was observed for a reduction to ~ 21 at.% when thermally evaporated indium sulphide was applied as the buffer layer. The influence of stoichiometry deviations on the transport mechanism and secondary barriers in the device was studied using detailed dark and light current-voltage analysis and admittance spectroscopy and compared to the reference CdS-buffered cells. We conclude that the composition of the absorber in the interface region affects current transport in In{sub x}S{sub y}-buffered and CdS-buffered cells in different ways hence optimal Cu content in those two types of devices is different. - Highlights: • Influence of Cu-variation in CIGS cells with In{sub x}S{sub y} buffer layer on cell performance • Enhanced efficiency by slight reduction of Cu-content to 21 at.% • Contribution of tunnelling-enhanced interface recombination for higher Cu-content.

Fragmentation of copper current collectors in Li-ion batteries during spherical indentation

International Nuclear Information System (INIS)

Wang, Hsin; Watkins, Thomas R.; Simunovic, Srdjan; Bingham, Philip R.; Allu, Srikanth; Turner, John A.

2017-01-01

Large, areal, brittle fracture of copper current collector foils was observed by 3D x-ray computed tomography (XCT) of a spherically indented Li-ion cell. This fracture was hidden and non-catastrophic to a degree because the graphite layers deformed plastically, and held the materials together so that the cracks in the foils could not be seen under optical and electron microscopy. 3D XCT on the indented cell showed “mud cracks” within the copper layer. The cracking of copper foils could not be immediately confirmed when the cell was opened for post-mortem examination. However, an X-ray radiograph on a single foil of the Cu anode showed clearly that the copper foil had broken into multiple pieces similar to the brittle cracking of a ceramic under indentation. This new failure mode of anodes on Li-ion cell has very important implications on the behavior of Li-ion cells under mechanical abuse conditions. Furthermore, the fragmentation of current collectors in the anode must be taken into consideration for the electrochemical responses which may lead to capacity loss and affect thermal runaway behavior of the cells.

Impact of non-selective fungicides on the growth and production of ochratoxin A by Aspergillus ochraceus and A. carbonarius in barley-based medium.

Science.gov (United States)

Mateo, Eva M; Valle-Algarra, F M; Mateo-Castro, R; Jimenez, M

2011-01-01

The aim of this study was to assess the influence of the non-selective fungicides mancozeb, copper oxychloride, and sulfur on the growth and capability for producing ochratoxin A (OTA) of ochratoxigenic isolates of Aspergillus carbonarius and A. ochraceus in barley-based medium. Lag phases and growth rates were determined for each fungicide at different doses, at 15°C and 25°C and at 0.97 a(w). Mancozeb at 40 mg l(-1 )inhibited fungal growth and provided lag phases >24 days at 10-20 mg l(-1) and 15°C. OTA was observed only at 25°C and doses Sulfur was inhibitory or provided large lag phases at 5-8 g l(-1) (at 15°C) while at 25°C growth took place even at 8 g l(-1), although OTA levels were low or undetectable. The antifungal activity decreased in the order mancozeb > copper oxychloride > sulfur, and was lower at 25°C than at 15°C. OTA accumulation was affected by the type of fungicide, dose, temperature and time. The efficacy of these fungicides on the growth of A. carbonarius and A. ochraceus and OTA production in barley-based medium is assessed for the first time.

Biochar and compost as amendments in copper-enriched vineyard soils - stabilization or mobilization of copper?

Science.gov (United States)

Soja, Gerhard; Fristak, Vladimir; Wimmer, Bernhard; Bell, Stephen; Chamier Glisczinski, Julia; Pardeller, Georg; Dersch, Georg; Rosner, Franz; Wenzel, Walter; Zehetner, Franz

2016-04-01

Copper is an important ingredient for several fungicides that have been used in agriculture. For organic viticulture, several diseases as e.g. downy mildew (Plasmopara viticola) can only be antagonized with Cu-containing fungicides. This long-lasting dependence on Cu-fungicides has led to a gradual Cu enrichment of vineyard soils in traditional wine-growing areas, occasionally exceeding 300 mg/kg. Although these concentrations do not affect the vines or wine quality, they may impair soil microbiological functions in the top soil layer or the root growth of green cover plants. Therefore measures are demanded that reduce the bioavailability of copper, thereby reducing the ecotoxicological effects. The use of biochar and compost as soil amendment has been suggested as a strategy to immobilize Cu and reduce the exchangeable fractions. This study consisted of lab and greenhouse experiments that were designed to test the sorption and desorption behavior of copper in vineyard soils with or without biochar and/or compost as soil amendment. Slightly acidic soils (pHeffects were more evident for a reduction of the ionic form Cu2+ than for total soluble copper, even in alkaline soils. Biochar modified with citric or tartaric acid did not significantly decrease the solubility of copper based on total dissolved concentrations although CEC was higher than in unmodified biochar. Treatments consisting of compost only or that had an equal amount of compost and biochar rather had a mobilizing effect on biochar. Sorption experiments with different DOC concentrations and biochar, however, showed a positive effect on copper sorption. Apparently in vineyard soils the predisposition to form organic-Cu-complexes may outbalance the binding possibilities of these complexes to biochar, occasionally resulting in enhanced mobilization. Presumably immobilization of copper with biochar would work best in acidic soils low in organic carbon and with low or no compost addition although this might

Copper and Copper Proteins in Parkinson's Disease

Science.gov (United States)

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

Evaluation of copper ion of antibacterial effect on Pseudomonas aeruginosa, Salmonella typhimurium and Helicobacter pylori and optical, mechanical properties

Energy Technology Data Exchange (ETDEWEB)

Kim, Young-Hwan [School of Materials Science and Engineering, University of Yonsei, Seoul (Korea, Republic of); Choi, Yu-ri; Kim, Kwang-Mahn [Department and Research Institute of Dental Biomaterials and Bioengineering, College of Dentistry, University of Yonsei, Seoul (Korea, Republic of); Choi, Se-Young, E-mail: sychoi@yonsei.ac.kr [School of Materials Science and Engineering, University of Yonsei, Seoul (Korea, Republic of)

2012-02-01

Antibacterial effect on Pseudomonas aeruginosa, Salmonella typhimurium and Helicobacter pylori of copper ion was researched. Also, additional effects of copper ion coating on optical and mechanical properties were researched as well. Copper ion was coated on glass substrate as a thin film to prevent bacteria from growing. Cupric nitrate was used as precursors for copper ion. The copper ion contained sol was deposited by spin coating process on glass substrate. Then, the deposited substrates were heat treated at the temperature range between 200 Degree-Sign C and 250 Degree-Sign C. The thickness of deposited copper layer on the surface was 63 nm. The antibacterial effect of copper ion coated glass on P. aeruginosa, S. typhimurium and H. pylori demonstrated excellent effect compared with parent glass. Copper ion contained layer on glass showed a similar value of transmittance compared with value of parent glass. The 3-point bending strength and Vickers hardness were 209.2 MPa, 540.9 kg/mm{sup 2} which were about 1.5% and 1.3% higher than the value of parent glass. From these findings, it is clear that copper ion coating on glass substrate showed outstanding effect not only in antibacterial activity but also in optical and mechanical properties as well.

Copper substrate as a catalyst for the oxidation of chemical vapor deposition-grown graphene

International Nuclear Information System (INIS)

Li, Zhiting; Zhou, Feng; Parobek, David; Shenoy, Ganesh J.; Muldoon, Patrick; Liu, Haitao

2015-01-01

We report the catalytic effect of copper substrate on graphene–oxygen reaction at high temperature. Previous studies showed that graphene grown on copper are mostly defect-free with strong oxidation resistance. We found that a freshly prepared copper-supported graphene sample can be completely oxidized in trace amount of oxygen (<3 ppm) at 600 °C within 2 h. Both X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) suggest that upon ambient air exposure, oxygen molecules diffuse into the space between graphene and copper, resulting in the formation of copper oxide which acts as catalytic sites for the graphene-oxygen reaction. This result has important implications for the characterization, processing, and storage of copper-supported graphene samples. - Graphical abstract: The copper substrate enhances the thermel oxidation of single-layer graphene. - Highlights: • A copper-supported graphene can be oxidized in Ar (O 2 <3 ppm, 600 °C, 2 h). • O 2 intercalates between graphene and copper upon exposure to air. • The copper foil should not be considered as an inert substrate

Deformation and fracture of Cu alloy-stainless steel layered structures under dynamic loading

International Nuclear Information System (INIS)

McCoy, J.H.; Kumar, A.S.

1998-01-01

Fracture resistance of the current ITER first wall configuration, a copper alloy-stainless steel layered structure, is a major design issue. The question of dynamic crack propagation into and through the first wall structure is examined using dynamic finite element modeling (FEM). Several layered configurations that incorporate both strain and frictional energy dissipation during the fracture process are considered. With fixed overall specimen geometry, the energy required to extend a precrack is examined as a function of material properties, and the layer structure. It is found that the crack extension energies vary dramatically with the fracture strain of materials, and to a much lesser extent with the number of layers. In addition, it is found that crack propagation through the lower ductility copper alloy layer may be deflected at the stainless steel-copper interface and not result in total fracture of the structure. Although the total energy required is affected only to a small degree by the interface properties, the time to extend the precrack is strongly affected. By making proper selections of the interface and the layered material, crack propagation rates and the possibility of full fracture can be substantially reduced. (orig.)

Separation of copper-64 from copper phthalocyanine

International Nuclear Information System (INIS)

Battaglin, R.I.M.

1979-01-01

The separation of copper-64 from irradiated copper phthalocyanine by Szilard-Chalmers effect is studied. Two methods of separation are used: one of them is based on the dissolution of the irradiated dry compound in concentrated sulfuric acid following its precipitation in water. In the other one the compound is irradiated with water in paste form following treatment with water and hydrochloric acid. The influence of the crystal form of the copper phthalocyanine on the separation yield of copper-64 is shown. Preliminary tests using the ionic exchange technique for purification and changing of copper-64 sulfate to chloride form are carried out. The specific activity using the spectrophotometric technique, after the determination of the copper concentration in solution of copper-64, is calculated. (Author) [pt

High-speed collision of copper nanoparticle with aluminum surface: Molecular dynamics simulation

Science.gov (United States)

Pogorelko, Victor V.; Mayer, Alexander E.; Krasnikov, Vasiliy S.

2016-12-01

We investigate the effect of the high-speed collision of copper nanoparticles with aluminum surface by means of molecular dynamic simulations. Studied diameter of nanoparticles is varied within the range 7.2-22 nm and the velocity of impact is equal to 500 or 1000 m/s. Dislocation analysis shows that a large quantity of dislocations is formed within the impact area. Overall length of dislocations is determined, first of all, by the impact velocity and by the size of incident copper nanoparticle, in other words, by the kinetic energy of the nanoparticle. Dislocations occupy the total volume of the impacted aluminum single crystal layer (40.5 nm in thickness) in the form of intertwined structure in the case of large kinetic energy of the incident nanoparticle. Decrease in the initial kinetic energy or increase in the layer thickness lead to restriction of the penetration depth of the dislocation net; formation of separate dislocation loops is observed in this case. Increase in the initial system temperature slightly raises the dislocation density inside the bombarded layer and considerably decreases the dislocation density inside the nanoparticle. The temperature increase also leads to a deeper penetration of the copper atoms inside the aluminum. Additional molecular dynamic simulations show that the deposited particles demonstrate a very good adhesion even in the case of the considered relatively large nanoparticles. Medium energy of the nanoparticles corresponding to velocity of about 500 m/s and elevated temperature of the system about 700-900 K are optimal parameters for production of high-quality layers of copper on the aluminum surface. These conditions provide both a good adhesion and a less degree of the plastic deformation. At the same time, higher impact velocities can be used for combined treatment consisting of both the plastic deformation and the coating.

Molecular dynamic simulations of the high-speed copper nanoparticles collision with the aluminum surface

Science.gov (United States)

Pogorelko, V. V.; Mayer, A. E.

2016-11-01

With the use of the molecular dynamic simulations, we investigated the effect of the high-speed (500 m/s, 1000 m/s) copper nanoparticle impact on the mechanical properties of an aluminum surface. Dislocation analysis shows that a large number of dislocations are formed in the impact area; the total length of dislocations is determined not only by the speed and size of the incoming copper nanoparticle (kinetic energy of the nanoparticle), but by a temperature of the system as well. The dislocations occupy the whole area of the aluminum single crystal at high kinetic energy of the nanoparticle. With the decrease of the nanoparticle kinetic energy, the dislocation structures are formed in the near-surface layer; formation of the dislocation loops takes place. Temperature rise of the system (aluminum substrate + nanoparticle) reduces the total dislocation length in the single crystal of aluminum; there is deeper penetration of the copper atoms in the aluminum at high temperatures. Average energy of the nanoparticles and room temperature of the system are optimal for production of high-quality layers of copper on the aluminum surface.

Interaction at interface between superconducting yttrium ceramics and copper or niobium

International Nuclear Information System (INIS)

Karpov, M.I.; Korzhov, V.P.; Medved', N.V.; Myshlyaeva, M.M.

1992-01-01

Light metallography, scanning electron microscopy and local energy dispersion analysis have been used to study the interaction of Y-ceramics with copper and niobium. Samples in the form of wire of two types were employed, that is, consisting of ceramic core YBaCuO and Cu shell or a ceramic core YBaCuO and bimetallic Cu/Nb shell. The interaction of the ceramics with the shell metal began already at 500 deg with the formation at the interafaces Cu-YBaCuO of oxide layers containing ceramic elements, and in the ceramic core - nonsuperconducting phases. A thin Al-layer placed between the ceramics and the shell appreciably decreased the reactability of the ceramics with respect to copper and niobium

Acid leaching of oxide-sulphide copper ore prior the flotation: A way for an increased metal recovery

Directory of Open Access Journals (Sweden)

Sokić Miroslav D.

2015-01-01

Full Text Available Copper mine "Cerovo"- East Serbia as well as the other ore bodies in its vicinity contain a significant amount of oxide copper minerals in their uper layers (>40%. Processing of such mixed ores by the existing concentration technologies leads to a substantial copper losses (<60%. Reduction of "oxide copper", by acid leaching prior the flotation concentration, can increase the overall copper efficiency up to more than 70% in the single-stage leaching, achieving an efficiency in the flotation concentration stage higher than 75%. Based on the performed experimental results the flow sheet for processing of the mixed oxide-sulphide copper ore is proposed.

Molecular dynamics study of Pb-substituted Cu(1 0 0) surface layers

Energy Technology Data Exchange (ETDEWEB)

Evangelakis, G.A. [Department of Physics, University of Ioannina, PO Box 1186, Ioannina 45110 (Greece); Pontikis, V., E-mail: Vassilis.pontikis@cea.f [Laboratoire des Solides Irradies, CEA-DRECAM, 91191 Gif-sur-Yvette Cedex (France)

2009-08-26

Using molecular dynamics (MD) and phenomenological n-body potentials from the literature, we have studied the structure of the uppermost layers of low-index surfaces in copper after partial substitution of copper by lead atoms at randomly selected sites. We found that lead atoms substituting copper strongly perturb the positions of nearest and of next-nearest neighbors thus triggering the setup of a disordered, nanometer-thick amorphous-like surface layer. Equilibrium atomic density profiles, computed along the [1 0 0] crystallographic direction, show that amorphous overlayers are largely metastable whereas the system displays a structured compositional profile of lead segregating at the interfaces. Similarities between our results and experimental findings are briefly discussed.

Molecular dynamics study of Pb-substituted Cu(1 0 0) surface layers

International Nuclear Information System (INIS)

Evangelakis, G.A.; Pontikis, V.

2009-01-01

Using molecular dynamics (MD) and phenomenological n-body potentials from the literature, we have studied the structure of the uppermost layers of low-index surfaces in copper after partial substitution of copper by lead atoms at randomly selected sites. We found that lead atoms substituting copper strongly perturb the positions of nearest and of next-nearest neighbors thus triggering the setup of a disordered, nanometer-thick amorphous-like surface layer. Equilibrium atomic density profiles, computed along the [1 0 0] crystallographic direction, show that amorphous overlayers are largely metastable whereas the system displays a structured compositional profile of lead segregating at the interfaces. Similarities between our results and experimental findings are briefly discussed.

Pure and Oxidized Copper Materials as Potential Antimicrobial Surfaces for Spaceflight Activities

Science.gov (United States)

Hahn, C.; Hans, M.; Hein, C.; Mancinelli, R. L.; Mücklich, F.; Wirth, R.; Rettberg, P.; Hellweg, C. E.; Moeller, R.

2017-12-01

Microbial biofilms can lead to persistent infections and degrade a variety of materials, and they are notorious for their persistence and resistance to eradication. During long-duration space missions, microbial biofilms present a danger to crew health and spacecraft integrity. The use of antimicrobial surfaces provides an alternative strategy for inhibiting microbial growth and biofilm formation to conventional cleaning procedures and the use of disinfectants. Antimicrobial surfaces contain organic or inorganic compounds, such as antimicrobial peptides or copper and silver, that inhibit microbial growth. The efficacy of wetted oxidized copper layers and pure copper surfaces as antimicrobial agents was tested by applying cultures of Escherichia coli and Staphylococcus cohnii to these metallic surfaces. Stainless steel surfaces were used as non-inhibitory control surfaces. The production of reactive oxygen species and membrane damage increased rapidly within 1 h of exposure on pure copper surfaces, but the effect on cell survival was negligible even after 2 h of exposure. However, longer exposure times of up to 4 h led to a rapid decrease in cell survival, whereby the survival of cells was additionally dependent on the exposed cell density. Finally, the release of metal ions was determined to identify a possible correlation between copper ions in suspension and cell survival. These measurements indicated a steady increase of free copper ions, which were released indirectly by cells presumably through excreted complexing agents. These data indicate that the application of antimicrobial surfaces in spaceflight facilities could improve crew health and mitigate material damage caused by microbial contamination and biofilm formation. Furthermore, the results of this study indicate that cuprous oxide layers were superior to pure copper surfaces related to the antimicrobial effect and that cell density is a significant factor that influences the time dependence of

Composition of Whiskers Grown on Copper in Repository Environment

International Nuclear Information System (INIS)

Hermansson, Hans-Peter; Tarkpea, Peeter; Holgersson, Stellan

2001-11-01

There is a hypothesis that a special family of local attack on copper based on growth of whiskers of sulfide, oxide/hydroxide and also carbonate/malachite could appear in the repository environment. It was earlier demonstrated that such whiskers could grow in a laboratory simulated repository environment, containing sulfide. A suggested composition of whiskers has earlier been forwarded but was not demonstrated. In the present work whiskers and their substrates were grown and characterized by investigations with a combination of SEM-EDS, XRD and LRS (Laser Raman Spectroscopy) techniques. SEM-EDS was used to determine the morphology and an elemental composition and distribution of whiskers and their substrate. A special effort was made to find out if the whisker growth is of a local or global character. The phase status could be determined locally and globally by combining XRD and LRS techniques on whiskers and substrates. Ideally, LRS gives a phase resolution down to a radius of 1 μm on the sample surface. This is of great value as it is of interest to study if there are phase differences in different parts of a whisker. Such information is important to understand the whisker growth mechanism. Cylindrical samples of pure copper were prepared and exposed to the selected de-aerated model groundwater containing, among other ions, chloride and sulfide. Exposure was performed in sealed glass flasks under de-aerated conditions. After exposure the copper sample was investigated on the surface, in cross section and on whiskers using the mentioned techniques. The results show that a black, easily detached layer of corrosion products is formed on the sample surface. The corrosion layer was subdivided into at least five parallel strata (probably more) of different composition. Numerous small pits and shallow pitting attacks with a larger radius were observed in the copper metal and the metal surface was in general very rough. A multitude of very easily detached whiskers or

Copper and copper-nickel alloys as zebra mussel antifoulants

Energy Technology Data Exchange (ETDEWEB)

Dormon, J.M.; Cottrell, C.M.; Allen, D.G.; Ackerman, J.D.; Spelt, J.K. [Univ. of Toronto, Ontario (Canada)

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.

Substrate considerations for graphene synthesis on thin copper films

International Nuclear Information System (INIS)

Howsare, Casey A; Robinson, Joshua A; Weng Xiaojun; Bojan, Vince; Snyder, David

2012-01-01

Chemical vapor deposition on copper substrates is a primary technique for synthesis of high quality graphene films over large areas. While well-developed processes are in place for catalytic growth of graphene on bulk copper substrates, chemical vapor deposition of graphene on thin films could provide a means for simplified device processing through the elimination of the layer transfer process. Recently, it was demonstrated that transfer-free growth and processing is possible on SiO 2 . However, the Cu/SiO 2 /Si material system must be stable at high temperatures for high quality transfer-free graphene. This study identifies the presence of interdiffusion at the Cu/SiO 2 interface and investigates the influence of metal (Ni, Cr, W) and insulating (Si 3 N 4 , Al 2 O 3 , HfO 2 ) diffusion barrier layers on Cu–SiO 2 interdiffusion, as well as graphene structural quality. Regardless of barrier choice, we find the presence of Cu diffusion into the silicon substrate as well as the presence of Cu–Si–O domains on the surface of the copper film. As a result, we investigate the choice of a sapphire substrate and present evidence that it is a robust substrate for synthesis and processing of high quality, transfer-free graphene. (paper)

Native oxide formation on pentagonal copper nanowires: A TEM study

Science.gov (United States)

Hajimammadov, Rashad; Mohl, Melinda; Kordas, Krisztian

2018-06-01

Hydrothermally synthesized copper nanowires were allowed to oxidize in air at room temperature and 30% constant humidity for the period of 22 days. The growth of native oxide layer was followed up by high-resolution transmission electron microscopy and diffraction to reveal and understand the kinetics of the oxidation process. Copper oxides appear in the form of differently oriented crystalline phases around the metallic core as a shell-like layer (Cu2O) and as nanoscopic islands (CuO) on the top of that. Time dependent oxide thickness data suggests that oxidation follows the field-assisted growth model at the beginning of the process, as practically immediately an oxide layer of ∼2.8 nm thickness develops on the surface. However, after this initial rapid growth, the local field attenuates and the classical parabolic diffusion limited growth plays the main role in the oxidation. Because of the single crystal facets on the side surface of penta-twinned Cu nanowires, the oxidation rate in the diffusion limited regime is lower than in polycrystalline films.

Application of a cold spray technique to the fabrication of a copper canister for the geological disposal of CANDU spent fuels

Energy Technology Data Exchange (ETDEWEB)

Choi, Heui-Joo, E-mail: hjchoi@kaeri.re.k [Korea Atomic Energy Research Institute, Radioactive Waste Management Technology Development, 150 Dukjin-dong, Yuseong, Daejon, 305-353 (Korea, Republic of); Lee, Minsoo; Lee, Jong Youl [Korea Atomic Energy Research Institute, Radioactive Waste Management Technology Development, 150 Dukjin-dong, Yuseong, Daejon, 305-353 (Korea, Republic of)

2010-10-15

A new method was proposed for the manufacture of a copper-cast iron canister for the spent fuel disposal based on the cold spray coating technique. The thickness of a copper shell could be fabricated to be as thin as 10 mm with the new method. Around 6 tons of copper could be saved with a 10 mm thick canister compared with a 50 mm thick canister. The electrochemical properties of the cold sprayed copper layer and forged copper were measured through a polarization test. The two copper layers showed very similar electrochemical properties. The lifetime of a 10 mm copper canister was estimated with a mathematical model based on the mass transport of sulfide ions through the buffer. The results showed that the canister lifetime was more than 140,000 years under the Korean granite groundwater condition. The thermal analysis with a current pre-conceptual design of a CANDU spent fuel canister showed that the maximum temperature between the canister and the saturated buffer was below the thermal criteria, 100 {sup o}C. Finally, the mechanical stability of the copper canister was confirmed with a computer program, ABAQUS, under the rock movement scenario.

Reversible and nonvolatile ferroelectric control of two-dimensional electronic transport properties of ZrCuSiAs-type copper oxyselenide thin films with a layered structure

Science.gov (United States)

Zhao, Xu-Wen; Gao, Guan-Yin; Yan, Jian-Min; Chen, Lei; Xu, Meng; Zhao, Wei-Yao; Xu, Zhi-Xue; Guo, Lei; Liu, Yu-Kuai; Li, Xiao-Guang; Wang, Yu; Zheng, Ren-Kui

2018-05-01

Copper-based ZrCuSiAs-type compounds of LnCuChO (Ln =Bi and lanthanides, Ch =S , Se, Te) with a layered crystal structure continuously attract worldwide attention in recent years. Although their high-temperature (T ≥ 300 K) electrical properties have been intensively studied, their low-temperature electronic transport properties are little known. In this paper, we report the integration of ZrCuSiAs-type copper oxyselenide thin films of B i0.94P b0.06CuSeO (BPCSO) with perovskite-type ferroelectric Pb (M g1 /3N b2 /3 ) O3-PbTi O3 (PMN-PT) single crystals in the form of ferroelectric field effect devices that allow us to control the electronic properties (e.g., carrier density, magnetoconductance, dephasing length, etc.) of BPCSO films in a reversible and nonvolatile manner by polarization switching at room temperature. Combining ferroelectric gating and magnetotransport measurements with the Hikami-Larkin-Nagaoka theory, we demonstrate two-dimensional (2D) electronic transport characteristics and weak antilocalization effect as well as strong carrier-density-mediated competition between weak antilocalization and weak localization in BPCSO films. Our results show that ferroelectric gating using PMN-PT provides an effective and convenient approach to probe the carrier-density-related 2D electronic transport properties of ZrCuSiAs-type copper oxyselenide thin films.

Copper and Copper Proteins in Parkinson’s Disease

Directory of Open Access Journals (Sweden)

Sergio Montes

2014-01-01

Full Text Available 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.

Growth of a Copper-Gold Alloy Phase by Bulk Copper Electrodeposition on Gold Investigated by In Situ STM

DEFF Research Database (Denmark)

Andersen, Jens Enevold Thaulov; Møller, Per

1995-01-01

the potential in the double-layer charging region from 500 to -100 mV and back to 500 mV at a sweep rate of 1 mV/s in an acidified copper sulfate electrolyte (0.01M H2SO4, 0.01M CuSO4, and Millipore water). After completion of the first cycle the gold surface had recrystallized and nuclei of an alloy phase were...... in peak potential for the anodic current transient from E = 20 mV to E = -2 mV was observed after completion of four subsequent cycles of copper electrodeposition/dissolution. The shift is suggested to be equal to the change in potential of the working electrode owing to the formation of the alloy phase....

Band bending at copper and gold interfaces with ferroelectric Pb(Zr,Ti)O{sub 3} investigated by photoelectron spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Apostol, Nicoleta G.; Ştoflea, Laura E.; Tănase, Liviu C.; Bucur, Ioana Cristina; Chirilă, Cristina; Negrea, Raluca F.; Teodorescu, Cristian M., E-mail: teodorescu@infim.ro

2015-11-01

Highlights: • Synthesis of lead zirco-titanate (0 0 1) layers with nearly perfect stoichiometric transfer from substrates by pulsed laser deposition. • Copper forms continuous layers on Pb(Zr,Ti)O{sub 3}, gold is deposited in form of nanoparticles. • Derivation of Schottky mechanism for band bending for gold deposited on lead zirco-titanate. • Cancellation of polarization-induced band bending for copper deposited on lead zirco-titanate. • Pb reduction observed only in the case of copper deposited on lead zirco-titanate. - Abstract: Interfaces formed by gold and copper on single crystal layers of (0 0 1) PbZr{sub 0.2}Ti{sub 0.8}O{sub 3} (PZT) produced by pulsed laser deposition and exhibiting outwards polarization are analyzed by X-ray photoelectron spectroscopy. The stoichiometry of the layers reproduces reasonably that of the PZT target. The band bending occurring at the interface between PZT and the metals is investigated by analyzing the core level shifts as function on the metal deposition. It is found that for Au/PZT(0 0 1) the gold layer is not continuous and the observed band bendings can be attributed to a Schottky mechanism, whereas for Cu/PZT(0 0 1) the copper layer is continuous; in this latter case, the observed band bendings towards higher energies (lower binding energies) can be attributed to a concomitant bending due to the Schottky effect together with the disappearance of the initial bending due to the outwards polarization of the samples. Metal Pb is observed to segregate only in the case of Cu/PZT(0 0 1), therefore the surface self-reduction might also be connected to the presence of a metal with lower work function, which for larger coverage forms a continuous metal layer, able to provide electrons to the surface. High resolution transmission electron spectroscopy yielded the disappearance of the tetragonal distortion in the case of Cu/PZT(0 0 1), in line with the assumption of disappearance of the polarization-induced band bending.

Investigation of copper(I sulphide leaching in oxidative hydrochloric acid solution

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Branislav Marković

2015-12-01

Full Text Available Present work is focused on the copper (I sulphide leaching with sodium chloride in hydrochloric acid solution and with introduction of gaseous oxygen. Chemical reactions of leaching and their thermodynamic probabilities are predicted based on the literature data and products which were formed during the process and the overall leaching reaction was defined. The influence of temperature and time on the leaching degree of copper was experimentally determined. The quantity of dissolved copper increases with the increase of both investigated parameters. Elemental sulphur was formed as the main leaching product, precipitated at the particle surfaces and chloride ions have a role to disrupt the creation of this passive layer.

Copper carrier protein in copper toxic sheep liver

Energy Technology Data Exchange (ETDEWEB)

Harris, A L; Dean, P D.G.

1973-01-01

The livers of copper-toxic sheep have been analyzed by gel electrophoresis followed by staining the gels for copper with diethyldithiocarbamate and for protein with amido schwartz. These gels were compared with similar gels obtained from the livers of normal and copper-deficient animals. The copper-toxic livers contained an extra protein band which possessed relatively weakly bound copper. Possible origins of this protein are discussed. 8 references, 1 figure, 2 tables.

A novel compound cleaning solution for benzotriazole removal after copper CMP

International Nuclear Information System (INIS)

Gu Zhangbing; Liu Yuling; Gao Baohong; Wang Chenwei; Deng Haiwen

2015-01-01

After the chemical mechanical planarization (CMP) process, the copper surface is contaminated by a mass of particles (e.g. silica) and organic residues (e.g. benzotriazole), which could do great harm to the integrated circuit, so post-CMP cleaning is essential. In particular, benzotriazole (BTA) forms a layer of Cu-BTA film with copper on the surface, which leads to a hydrophobic surface of copper. So an effective cleaning solution is needed to remove BTA from the copper surface. In this work, a new compound cleaning solution is designed to solve two major problems caused by BTA: one is removing BTA and the other is copper surface corrosion that is caused by the cleaning solution. The cleaning solution is formed of alkaline chelating agent (FA/O II type), which is used to remove BTA, and a surfactant (FA/O I type), which is used as a corrosion inhibitor. BTA removal is characterized by contact angle measurements and electrochemical techniques. The inhibiting corrosion ability of the surfactant is also characterized by electrochemical techniques. The proposed compound cleaning solution shows advantages in removing BTA without corroding the copper surface. (paper)

The analysis of beryllium-copper diffusion joint after HHF test

International Nuclear Information System (INIS)

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

1995-01-01

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 2 Be (∼170 μm), CuBe (∼30μm), CuBe 2 (∼1 μm) and solid solution of copper in beryllium. The phases Cu 2 Be, CuBe and solid solution of copper in beryllium were indicated using quantitative microanalysis and phases CuBe, CuBe 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

Interaction of copper metallization with rare-earth metals and silicides

International Nuclear Information System (INIS)

Molnar, G. L.; Peto, G.; Zsoldos, E.; Horvath, Z. E.

2001-01-01

Solid-phase reactions of copper films with underlying gadolinium, erbium, and erbium - silicide layers on Si(100) substrates were investigated. For the phase analysis, x-ray diffraction and cross-sectional transmission electron microscopy were used. In the case of Cu/Gd/Si(100), an orthorhombic GdSi 2 formed, and, at higher temperatures, copper aggregated into islands. Annealed Cu/Er/Si(100) samples resulted in a hexagonal Er 5 Si 3 phase. In the Cu/ErSi 2-x /Si system, the copper catalyzes the transformation of the highly oriented hexagonal ErSi 2-x phase into hexagonal Er 5 Si 3 . Diverse phase developments of the samples with Gd and Er are based on reactivity differences of the two rare-earth metals. [copyright] 2001 American Institute of Physics

Copper and copper-nickel-alloys - An overview

Energy Technology Data Exchange (ETDEWEB)

Klassert, Anton; Tikana, Ladji [Deutsches Kupferinstitut e.V. Am Bonneshof 5, 40474 Duesseldorf (Germany)

2004-07-01

With the increasing level of industrialization the demand for and the number of copper alloys rose in an uninterrupted way. Today, the copper alloys take an important position amongst metallic materials due to the large variety of their technological properties and applications. Nowadays there exist over 3.000 standardized alloys. Copper takes the third place of all metals with a worldwide consumption of over 15 millions tons per year, following only to steel and aluminum. In a modern industrial society we meet copper in all ranges of the life (electro-technology, building and construction industry, mechanical engineering, automotive, chemistry, offshore, marine engineering, medical applications and others.). Copper is the first metal customized by humanity. Its name is attributed to the island Cyprus, which supplied in the antiquity copper to Greece, Rome and the other Mediterranean countries. The Romans called it 'ore from Cyprus' (aes cyprium), later cuprum. Copper deposited occasionally also dapper and could be processed in the recent stone age simply by hammering. Already in early historical time copper alloys with 20 to 50 percent tin was used for the production of mirrors because of their high reflecting power. Although the elementary nickel is an element discovered only recently from a historical perspective, its application in alloys - without any knowledge of the alloy composition - occurred at least throughout the last 2.000 years. The oldest copper-nickel coin originates from the time around 235 B.C.. Only around 1800 AD nickel was isolated as a metallic element. In particular in the sea and offshore technology copper nickel alloys found a broad field of applications in piping systems and for valves and armatures. The excellent combination of characteristics like corrosion resistance, erosion stability and bio-fouling resistance with excellent mechanical strength are at the basis of this success. An experience of many decades supports the use

Impedance spectroscopy for the study of anodic copper dissolution in sulfuric acid in presence of benzotriazole

International Nuclear Information System (INIS)

Clerc, C.; Alkire, R.C.

1988-01-01

The presence of an anodic surface film dramatically affects the electrochemical behavior of dissolving electrode in processes like corrosion inhibition, passivity, electropolishing or pitting. The present study was initiated to learn more about the physical properties of the surface films present at the surface of a copper electrode during anodic dissolution in 0.5 SM sulfuric acid and 40 mM benzotriazole (BTA) at 25 0 C. This study is of practical importance because this organic compound is widely used for corrosion inhibition and as etching additive. The impedance spectra measured after 10 min of polarization (with a SOLARTRAN 1250 Frequency Response Analyzer and a SOLARTRON 1286 Electrochemical Interface) were analyzed by comparison with a physical model of the electrochemical interface in which the passive electrode is covered with a barrier layer. The main assumptions are that this barrier layer is a good electronic insulator of stoichiometric composition and that charge transfer reactions and double layer charging occur at both metal-barrier layer and barrier layer-electrolyte interphases. This model also considers the change in the barrier layer thickness under the influence of the applied potential. Least squares fitting of measured impedance spectra yield physical parameters of reasonable order of magnitude to support the proposed model. As predicted it was found that the barrier layer is itself covered by an outer porous film of corrosion products and that the metallic ions transfer through the barrier layer under high field conduction. By comparing the crystallographic lattice parameters and the dielectric constants of different copper compounds, the jump distance was determined to be about 5.5 A, indicating that the barrier layer is likely to be an hydrated copper sulfate (CuSO/sub 4/ 5H/sub 2/O)

The Acute Oral Toxicity of Commonly Used Pesticides in Iran, to Honeybees (Apis Mellifera Meda

Directory of Open Access Journals (Sweden)

Rasuli Farhang

2015-06-01

Full Text Available The honey bee is credited with approximately 85% of the pollinating activity necessary to supply about one-third of the world’s food supply. Well over 50 major crops depend on these insects for pollination. The crops produce more abundantly when honey bees are plentiful. Worker bees are the ones primarily affected by pesticides. Poisoning symptoms can vary depending on the developmental stage of the individual bee, and the kind of chemical employed. The oral toxicity of these insecticides: (phosalone and pirimicarb, acaricide (propargite, insecticide and acaricide (fenpropathrin, fungicides, and bactericides (copper oxychloride and the Bordeaux mixture, were evaluated for the purposes of this research. The results showed that fenpropathrin had high acute oral toxicity (LC50-24h and LC50-48 were 0.54 and 0.3 ppm, respectively. Propargite had 7785 ppm (active ingredient for LC50-24h and 6736 ppm (active ingredient for LC50-48h in honeybees and is therefore, non-toxic to Apis mellifera. On the other hand, copper oxychloride had minimum acute oral toxicity to honeybees (LC50-24h and LC50-48 were 4591.5 and 5407.9 ppm, respectively and was therefore considered non-toxic. Also, the Bordeaux mixture was safe to use around honeybees. Phosalone and primicarb were considered highly and moderately toxic to honeybees, respectively.

Chemical products induce resistance to Xanthomonas perforans in tomato

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Adriana Terumi Itako

2015-09-01

Full Text Available The bacterial spot of tomato, caused by Xanthomonas spp., is a very important disease, especially in the hot and humid periods of the year. The chemical control of the disease has not been very effective for a number of reasons. This study aimed to evaluate, under greenhouse conditions, the efficacy of leaf-spraying chemicals (acibenzolar-S-methyl (ASM (0.025 g.L−1, fluazinam (0.25 g.L−1, pyraclostrobin (0.08 g.L−1, pyraclostrobin + methiran (0.02 g.L−1 + 2.2 g.L−1, copper oxychloride (1.50 g.L−1, mancozeb + copper oxychloride (0.88 g.L−1 + 0.60 g.L−1, and oxytetracycline (0.40 g.L−1 on control of bacterial spot. Tomatoes Santa Clara and Gisele cultivars were pulverized 3 days before inoculation with Xanthomonas perforans. The production of enzymes associated with resistance induction (peroxidase, polyphenol oxidase, phenylalanine ammonia-lyase, β-1,3-glucanase, and protease was quantified from leaf samples collected 24 hours before and 24 hours after chemical spraying and at 1, 2, 4, 6, and 8 days after bacterial inoculation. All products tested controlled bacterial spot, but only ASM, pyraclostrobin, and pyraclostrobin + metiram increased the production of peroxidase in the leaves of the two tomato cultivars, and increased the production of polyphenol oxidase and β-1,3-glucanase in the Santa Clara cultivar.

Chemical products induce resistance to Xanthomonas perforans in tomato.

Science.gov (United States)

Itako, Adriana Terumi; Tolentino Júnior, João Batista; Silva Júnior, Tadeu Antônio Fernandes da; Soman, José Marcelo; Maringoni, Antonio Carlos

2015-01-01

The bacterial spot of tomato, caused by Xanthomonas spp., is a very important disease, especially in the hot and humid periods of the year. The chemical control of the disease has not been very effective for a number of reasons. This study aimed to evaluate, under greenhouse conditions, the efficacy of leaf-spraying chemicals (acibenzolar-S-methyl (ASM) (0.025 g.L(-1)), fluazinam (0.25 g.L(-1)), pyraclostrobin (0.08 g.L(-1)), pyraclostrobin + methiran (0.02 g.L(-1) + 2.2 g.L(-1)), copper oxychloride (1.50 g.L(-1)), mancozeb + copper oxychloride (0.88 g.L(-1) + 0.60 g.L(-1)), and oxytetracycline (0.40 g.L(-1))) on control of bacterial spot. Tomatoes Santa Clara and Gisele cultivars were pulverized 3 days before inoculation with Xanthomonas perforans. The production of enzymes associated with resistance induction (peroxidase, polyphenol oxidase, phenylalanine ammonia-lyase, β-1,3-glucanase, and protease) was quantified from leaf samples collected 24 hours before and 24 hours after chemical spraying and at 1, 2, 4, 6, and 8 days after bacterial inoculation. All products tested controlled bacterial spot, but only ASM, pyraclostrobin, and pyraclostrobin + metiram increased the production of peroxidase in the leaves of the two tomato cultivars, and increased the production of polyphenol oxidase and β-1,3-glucanase in the Santa Clara cultivar.

Magnetoresistant Co/Cu multilayers: effect of crystallographic orientation of the layers

International Nuclear Information System (INIS)

Boher, P.; Giron, F.; Houdy, P.; Beauvillain, P.; Chappert, C.; Veillet, P.

1992-01-01

In the last few years ferromagnetic/non-ferromagnetic multilayers have received considerable attention due to their great interest formagnetoresistive applications. Giant magnetoresistance has been observed in the Cu/Co system but with quite high saturation field (>>1 kOe). In this paper we report on an original way to enhance this characterisitc, using unusual fcc left angle 100 right angle cristallographic orientation. Special preparation of the right angle 100 right angle silicon substrates is investigated using in-situ kinetic ellipsometry, RHEED, grazing X-ray reflection and X-ray diffraction. We show that good quality fcc right angle 100 right angle pseudo-epitaxial copper surface can be obtained only when two conditions are fulfilled: first the silicon surface must be completely free of native oxide and second the copper buffer layer must be annealed under ultrahigh vacuum. Perfectly clean silicon surfaces are obtained by chemical etching followed by flash heating under ultrahigh vacuum. The copper buffer layer reacts with silicon and gives a textured fcc right angle 100 right angle Cu phase with a 45 rotation of the Cu left angle 100 right angle lattice with regards to the Si right angle 100 right angle one. Additional annealing leads to an homogencous interface silicide layer and improves the cristallinity of the Cu buffer layer. Cu/Co multilayers deposited on this kind of substrate show a well-defined fcc right angle 100 right angle texture for a large range of layer thickness. Oscillation of magnetoresistance with the copper thickness is observed with a period of about 10 A. The maximum of magnetoresistance is found for 20.9 A of Cu (ΔR/R∼6%), and the differential magnetoresistance is very high (ΔR/RΔH = 1.4 kOe -1 ). Combination of antiferromagnetic coupling and quadratic in-plane anisotropy of this special cristallographic orientation is responsible for this improvement. (orig.)

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

Science.gov (United States)

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.

Angular distributions of sputtered particles from lithium-implanted aluminium and copper crystals

International Nuclear Information System (INIS)

Johansen, A.; Johnson, E.; Sarholt-Kristensen, L.; Steenstrup, S.; Andersen, H.H.; Buhanov, V.M.; Chernysh, V.S.; Ivanov, I.N.; Minnebaev, K.F.

1991-01-01

The anisotropy of angular distributions of sputtered ions from lithium implanted aluminium and copper single crystals, measured by SIMS analysis, have been used to obtain information about the microstructure of the implanted layers. Sputtered Al + distributions from the {111} surface show three-fold symmetry with maximum intensity near the and directions respectively, while Li + distributions show maximum intensity only in the directions. From {100} crystals the Al + distributions have four-fold symmetry while there are no preferential ejection directions for the Li + ions. This agrees conceptually with the fact that the implanted layer contains the ordered Al 3 Li (δ') phase, which has earlier been observed by TEM analysis on implanted samples. In contrast, a similar study of Li + implanted copper crystals shows that the implanted lithium is randomly located. (orig.)

Advanced Copper Composites Against Copper-Tolerant Xanthomonas perforans and Tomato Bacterial Spot.

Science.gov (United States)

Strayer-Scherer, A; Liao, Y Y; Young, M; Ritchie, L; Vallad, G E; Santra, S; Freeman, J H; Clark, D; Jones, J B; Paret, M L

2018-02-01

Bacterial spot, caused by Xanthomonas spp., is a widespread and damaging bacterial disease of tomato (Solanum lycopersicum). For disease management, growers rely on copper bactericides, which are often ineffective due to the presence of copper-tolerant Xanthomonas strains. This study evaluated the antibacterial activity of the new copper composites core-shell copper (CS-Cu), multivalent copper (MV-Cu), and fixed quaternary ammonium copper (FQ-Cu) as potential alternatives to commercially available micron-sized copper bactericides for controlling copper-tolerant Xanthomonas perforans. In vitro, metallic copper from CS-Cu and FQ-Cu at 100 μg/ml killed the copper-tolerant X. perforans strain within 1 h of exposure. In contrast, none of the micron-sized copper rates (100 to 1,000 μg/ml) from Kocide 3000 significantly reduced copper-tolerant X. perforans populations after 48 h of exposure compared with the water control (P copper-based treatments killed the copper-sensitive X. perforans strain within 1 h. Greenhouse studies demonstrated that all copper composites significantly reduced bacterial spot disease severity when compared with copper-mancozeb and water controls (P copper composites significantly reduced disease severity when compared with water controls, using 80% less metallic copper in comparison with copper-mancozeb in field studies (P copper composites have the potential to manage copper-tolerant X. perforans and tomato bacterial spot.

Eco-Friendly Inhibitors for Copper Corrosion in Nitric Acid: Experimental and Theoretical Evaluation

Science.gov (United States)

Savita; Mourya, Punita; Chaubey, Namrata; Singh, V. K.; Singh, M. M.

2016-02-01

The inhibitive performance of Vitex negundo, Adhatoda vasica, and Saraka asoka leaf extracts on corrosion of copper in 3M HNO3 solution was investigated using gravimetric, potentiodynamic polarization, and electrochemical impedance spectroscopic techniques. Potentiodynamic polarization studies indicated that these extracts act as efficient and predominantly cathodic mixed inhibitor. Thermodynamic parameters revealed that the adsorption of these inhibitors on copper surface was spontaneous, controlled by physiochemical processes and occurred according to the Langmuir adsorption isotherm. AFM examination of copper surface confirmed that the inhibitor prevented corrosion by forming protective layer on its surface. The correlation between inhibitive effect and molecular structure was ascertained by density functional theory data.

Copper (I) Selenocyanate (CuSeCN) as a Novel Hole-Transport Layer for Transistors, Organic Solar Cells, and Light-Emitting Diodes

KAUST Repository

Wijeyasinghe, Nilushi; Tsetseris, Leonidas; Regoutz, Anna; Sit, Wai-Yu; Fei, Zhuping; Du, Tian; Wang, Xuhua; McLachlan, Martyn A.; Vourlias, George; Patsalas, Panos A.; Payne, David J.; Heeney, Martin; Anthopoulos, Thomas D.

2018-01-01

The synthesis and characterization of copper (I) selenocyanate (CuSeCN) and its application as a solution-processable hole-transport layer (HTL) material in transistors, organic light-emitting diodes, and solar cells are reported. Density-functional theory calculations combined with X-ray photoelectron spectroscopy are used to elucidate the electronic band structure, density of states, and microstructure of CuSeCN. Solution-processed layers are found to be nanocrystalline and optically transparent (>94%), due to the large bandgap of ≥3.1 eV, with a valence band maximum located at −5.1 eV. Hole-transport analysis performed using field-effect measurements confirms the p-type character of CuSeCN yielding a hole mobility of 0.002 cm2 V−1 s−1. When CuSeCN is incorporated as the HTL material in organic light-emitting diodes and organic solar cells, the resulting devices exhibit comparable or improved performance to control devices based on commercially available poly(3,4-ethylenedioxythiophene):polystyrene sulfonate as the HTL. This is the first report on the semiconducting character of CuSeCN and it highlights the tremendous potential for further developments in the area of metal pseudohalides.

Copper (I) Selenocyanate (CuSeCN) as a Novel Hole-Transport Layer for Transistors, Organic Solar Cells, and Light-Emitting Diodes

KAUST Repository

Wijeyasinghe, Nilushi

2018-02-01

The synthesis and characterization of copper (I) selenocyanate (CuSeCN) and its application as a solution-processable hole-transport layer (HTL) material in transistors, organic light-emitting diodes, and solar cells are reported. Density-functional theory calculations combined with X-ray photoelectron spectroscopy are used to elucidate the electronic band structure, density of states, and microstructure of CuSeCN. Solution-processed layers are found to be nanocrystalline and optically transparent (>94%), due to the large bandgap of ≥3.1 eV, with a valence band maximum located at −5.1 eV. Hole-transport analysis performed using field-effect measurements confirms the p-type character of CuSeCN yielding a hole mobility of 0.002 cm2 V−1 s−1. When CuSeCN is incorporated as the HTL material in organic light-emitting diodes and organic solar cells, the resulting devices exhibit comparable or improved performance to control devices based on commercially available poly(3,4-ethylenedioxythiophene):polystyrene sulfonate as the HTL. This is the first report on the semiconducting character of CuSeCN and it highlights the tremendous potential for further developments in the area of metal pseudohalides.

Deposition of Antimicrobial Copper-Rich Coatings on Polymers by Atmospheric Pressure Jet Plasmas

Directory of Open Access Journals (Sweden)

Jana Kredl

2016-04-01

Full Text Available Inanimate surfaces serve as a permanent reservoir for infectious microorganisms, which is a growing problem in areas in everyday life. Coating of surfaces with inorganic antimicrobials, such as copper, can contribute to reduce the adherence and growth of microorganisms. The use of a DC operated air plasma jet for the deposition of copper thin films on acrylonitrile butadiene styrene (ABS substrates is reported. ABS is a widespread material used in consumer applications, including hospitals. The influence of gas flow rate and input current on thin film characteristics and its bactericidal effect have been studied. Results from X-ray photoelectron spectroscopy (XPS and atomic force microscopy confirmed the presence of thin copper layers on plasma-exposed ABS and the formation of copper particles with a size in the range from 20 to 100 nm, respectively. The bactericidal properties of the copper-coated surfaces were tested against Staphylococcus aureus. A reduction in growth by 93% compared with the attachment of bacteria on untreated samples was observed for coverage of the surface with 7 at. % copper.

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

Science.gov (United States)

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

Type I fitting of copper tubes from a water distribution system

CSIR Research Space (South Africa)

Fernandes, PJL

1998-03-01

Full Text Available with a greenish scale of a copper compound called malachite. Beneath this scale, the tube surface is covered with a smooth, shiny layer of dark cuprite which is very friable and easily spalled off. Pits are usually...

Novel building units with bimetallic rings in inorganic/organic hybrid chains and layers

International Nuclear Information System (INIS)

Mahenthirarajah, Thushitha; Li Yang; Lightfoot, Philip

2009-01-01

Hydrothermal synthesis has produced three new compounds constructed from novel building units containing vanadium-oxide (or oxyfluoride) subunits linked together via covalently bound cationic copper complexes. Each new compound exhibits novel structural features: [Cu(dipa)][VOF 4 ] (1) incorporates a corner-sharing octahedral vanadium(IV) oxyfluoride chain decorated by copper-(2,2'-dipyridyl amine) complexes which form intra-chain bridges. Within a similar reactant system [Cu(dipa)] 2 [V 6 O 17 ] (2) is produced, the structure of which exhibits edge-sharing trigonal bipyramidal vanadium(V) 'ladder-like' double chains which are bridged into layers by tetrahedral pyrovanadate dimers together with the copper-(2,2'-dipyridyl amine) complexes. [Cu(py) 4 ] 2 [V 4 O 12 ] (3), is a 2-D structure featuring exclusively tetrahedral vanadium(V) in four-membered ring building blocks, linked through octahedral copper-pyridine complexes to form two crystallographically different bimetallic layers. - Graphical abstract: Hydrothermal synthesis is used to prepare hybrid mixed metal oxides and oxyfluorides with novel extended connectivities

Influence of oxygen, albumin and pH on copper dissolution in a simulated uterine fluid.

Science.gov (United States)

Bastidas, D M; Cano, E; Mora, E M

2005-06-01

The aim of this paper is to study the influence of albumin content, from 5 to 45 g/L, on copper dissolution and compounds composition in a simulated uterine solution. Experiments were performed in atmospheric pressure conditions and with an additional oxygen pressure of 0.2 atmospheres, at 6.3 and 8.0 pH values, and at a temperature of 37 +/- 0.1 degrees C for 1, 3, 7, and 30 days experimentation time. The copper dissolution rate has been determined using absorbance measurements, finding the highest value for pH 8.0, 35 g/L albumin, and with an additional oxygen pressure of 0.2 atmospheres: 674 microg/day for 1 day, and 301 microg/day for 30 days. X-ray photoelectron spectroscopy (XPS) results show copper(II) as the main copper oxidation state at pH 8.0; and copper(I) and metallic copper at pH 6.3. The presence of albumin up to 35 g/L, accelerates copper dissolution. For high albumin content a stabilisation on the copper dissolution takes place. Corrosion product layer morphology is poorly protective, showing paths through which copper ions can release.

Fast Photo-detection in Phototransistors based on Group III-VI Layered Materials.

Science.gov (United States)

Patil, Prasanna; Ghosh, Sujoy; Wasala, Milinda; Lei, Sidong; Vajtai, Robert; Ajayan, Pulickel; Talapatra, Saikat

Response time of a photo detector is one of the crucial aspect of photo-detection. Recently it has been shown that direct band gap of few layered group III-VI materials helps in increased absorption of light thereby enhancing the photo responsive properties of these materials. Ternary system of Copper Indium Selenide has been extensively used in optoelectronics industry and it is expected that 2D layered structure of Copper Indium Selenide will be a key component of future optoelectronics devices based on 2D materials. Here we report fast photo detection in few layers of Copper Indium Selenide (CuIn7Se11) phototransistor. Few-layers of CuIn7Se11 flakes were exfoliated from crystals grown using chemical vapor transport technique. Our photo response characterization indicates responsivity of 104 mA/W with external quantum efficiency exceeding 103. We have found response time of few μs which is one of the fastest response among photodetectors based on 2D materials. We also found specific detectivity of 1012 Jones which is an order higher than conventional photodetectors. A comparison between response times of various layered group III-VI materials will be presented and discussed. This work is supported by the U.S. Army Research Office through a MURI Grant # W911NF-11-1-0362.

Copper corrosion experiments under anoxic conditions

Energy Technology Data Exchange (ETDEWEB)

Ollila, Kaija [VTT Technical Research Centre of Finland, Espoo (Finland)

2013-06-15

This report gives results from the corrosion experiments with copper under anoxic conditions. The objective was to study whether hydrogen-evolving corrosion reaction could occur. Copper foil samples were exposed in deaerated deionized water in Erlenmeyer flasks in the glove box with inert atmosphere. Four corrosion experiments (Cu1, Cu2, Cu3 and Cu4) were started, as well as a reference test standing in air. Cu1 and Cu2 had gas tight seals, whereas Cu3 and Cu4 had palladium foils as hydrogen permeable enclosure. The test vessels were stored during the experiments in a closed stainless steel vessel to protect them from the trace oxygen of the gas atmosphere and light. After the reaction time of three and a half years, there were no visible changes in the copper surfaces in any of the tests in the glove box, in contrast the Cu surfaces looked shiny and unaltered. The Cu3 test was terminated after the reaction time of 746 days. The analysis of the Pd-membrane showed the presence of H2 in the test system. If the measured amount of 7.2{center_dot}10{sup 5} mol H{sub 2} was the result of formation of Cu{sub 2}O this would correspond to a 200 nm thick corrosion layer. This was not in agreement with the measured layer thickness with SIMS, which was 6{+-}1 nm. A clear weight loss observed for the Cu3 test vessel throughout the test period suggests the evaporation of water through the epoxy sealing to the closed steel vessel. If this occurred, the anaerobic corrosion of steel surface in humid oxygen-free atmosphere could be a source of hydrogen. A similar weight loss was not observed for the parallel test (Cu4). The reference test standing in air showed visible development of corrosion products.

Native copper as a natural analogue for copper canisters

International Nuclear Information System (INIS)

Marcos, N.

1989-12-01

This paper discusses the occurrence of native copper as found in geological formations as a stability analogue of copper canisters that are planned to be used for the disposal of spent nuclear fuel in the Finnish bedrock. A summary of several publications on native copper occurrences is presented. The present geochemical and geohydrological conditions in which copper is met with in its metallic state show that metallic copper is stable in a wide range of temperatures. At low temperatures native copper is found to be stable where groundwater has moderate pH (about 7), low Eh (< +100 mV), and low total dissolved solids, especially chloride. Microscopical and microanalytical studies were carried out on a dozen of rock samples containing native copper. The results reveal that the metal shows no significant alteration. Only the surface of copper grains is locally coated. In the oldest samples there exist small corrosion cracks; the age of the oldest samples is over 1,000 million years. A review of several Finnish groundwater studies suggests that there are places in Finland where the geohydrological conditions are favourable for native copper stability. (orig.)

Effect of acrylonitrile on the electrode processes ivolving copper cations

Directory of Open Access Journals (Sweden)

Viktor F. Vargalyuk

2016-03-01

Full Text Available Based on the results of cyclic voltammetry and study of deposits morphology, it has been shown that acrylonitrile does not have significant effect on the mechanism of Cu2+ + 2ē → Cu0 reaction. This distinguishes acrylonitrile from the unsaturated polyfunctional organic substances (acrylic acid, acrylamide which forms stable complexes with Cu2+ ions. Acrylonitrile just inhibits cathodic process by adsorbing on the surface of electrode thus blocking its active sites. But the presence of acrylonitrile significantly changes the mechanism of the anodic process. It has been found that acrylonitrile interacts with surface copper atoms thus forming thermodynamically stable [Cu π-AN]0 π‑complexes. Ionization potential of these π‑complexes is more negative if compare to copper atoms. As the result acceleration of anodic process takes place in the low polarization area. However, since the chemisorption is a slow process the presence of acrylonitrile mainly affects dissolution of the first surface layers of copper atoms. Further ionization of copper atoms runs out directly and requires higher polarization.

Influence of titanium oxide films on copper nucleation during electrodeposition

International Nuclear Information System (INIS)

Chang, Hyun K.; Choe, Byung-Hak; Lee, Jong K.

2005-01-01

Copper electrodeposition has an important industrial role because of various interconnects used in electronic devices such as printed wire boards. With an increasing trend in device miniaturization, in demand are void-free, thin copper foils of 10 μm thick or less with a very low surface profile. In accordance, nucleation kinetics of copper was studied with titanium cathodes that were covered with thin, passive oxide films of 2-3 nm. Such an insulating oxide layer with a band gap of 3 eV is supposed to nearly block charge transfer from the cathode to the electrolyte. However, significant nucleation rates of copper were observed. Pipe tunneling mechanism along a dislocation core is reasoned to account for the high nucleation kinetics. A dislocation core is proposed to be a high electron tunneling path with a reduced energy barrier and a reduced barrier thickness. In supporting the pipe tunneling mechanism, both 'in situ' and 'ex situ' scratch tests were performed to introduce extra dislocations into the cathode surface, that is, more high charge paths via tunneling, before electrodeposition

Phosphate ions as inhibiting agents for copper corrosion in chlorinated tap water

International Nuclear Information System (INIS)

Yohai, L.; Schreiner, W.H.; Vázquez, M.; Valcarce, M.B.

2013-01-01

PO 4 3− ions as corrosion inhibitor were investigated on copper in tap water in the presence of NaClO. The inhibitor was evaluated by electrochemical techniques and weight loss tests. Raman spectroscopy and X-ray photoelectron spectroscopy were used to study the passive layer. In inhibited tap water, the passive layer is thick and compact if NaClO is present. Weight-loss tests showed the inhibition of uniform dissolution and no pitting attack. When adding NaClO, Cu 3 (PO 4 ) 2 is incorporated to the passive film. Thus, phosphate ions are effective as inhibitors for copper in tap water, even when using high dosages of biocides. - Highlights: ► Changes in the copper corrosion after adding phosphate to tap water were analyzed. ► When NaClO and phosphates are present, Cu 3 (PO 4 ) 2 participates of the surface film. ► In the absence of biocide the surface film contains a mixture of Cu 2 O, CuO and Cu(OH) 2 . ► PO 4 3− is an effective inhibitor for Cu in tap water containing high NaClO dosages

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

Science.gov (United States)

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).

COPPER AND COPPER-CONTAINING PESTICIDES: METABOLISM, TOXICITY AND OXIDATIVE STRESS

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Viktor Husak

2015-05-01

Full Text Available The purpose of this paper is to provide a brief review of the current knowledge regarding metabolism and toxicity of copper and copper-based pesticides in living organisms. Copper is an essential trace element in all living organisms (bacteria, fungi, plants, and animals, because it participates in different metabolic processes and maintain functions of organisms. The transport and metabolism of copper in living organisms is currently the subject of many studies. Copper is absorbed, transported, distributed, stored, and excreted in the body via the complex of homeostatic processes, which provide organisms with a needed constant level of this micronutrient and avoid excessive amounts. Many aspects of copper homeostasis were studied at the molecular level. Copper based-pesticides, in particularly fungicides, bacteriocides and herbicides, are widely used in agricultural practice throughout the world. Copper is an integral part of antioxidant enzymes, particularly copper-zinc superoxide dismutase (Cu,Zn-SOD, and plays prominent roles in iron homeostasis. On the other hand, excess of copper in organism has deleterious effect, because it stimulates free radical production in the cell, induces lipid peroxidation, and disturbs the total antioxidant capacity of the body. The mechanisms of copper toxicity are discussed in this review also.

Some features of the molecular assembly of copper porphyrazines

International Nuclear Information System (INIS)

Valkova, L.; Borovkov, N.; Kopranenkov, V.; Pisani, M.; Bossi, M.; Rustichelli, F.

2002-01-01

Floating layers and Langmuir-Blodgett (LB) films of copper porphyrazine (CuPaz) and its tetra-tert-butyl-substituted homologue (CuPaz') are studied. Contrary to phthalocyanines, the monolayer phase in the porphyrazine layers is metastable and transforms directly into the tetralayer one under moderate compression. In diffraction patterns and electronic spectra of the LB films, supramolecular peaks indicating collectivizing of the molecular electron density in direction perpendicular to the main axis of the macrocycle are found. The data obtained indicate the prismatic 3-D supermolecule to be the simplest structural unit of the porphyrazine assembly

Uptake and internalisation of copper by three marine microalgae: comparison of copper-sensitive and copper-tolerant species.

Science.gov (United States)

Levy, Jacqueline L; Angel, Brad M; Stauber, Jennifer L; Poon, Wing L; Simpson, Stuart L; Cheng, Shuk Han; Jolley, Dianne F

2008-08-29

Although it has been well established that different species of marine algae have different sensitivities to metals, our understanding of the physiological and biochemical basis for these differences is limited. This study investigated copper adsorption and internalisation in three algal species with differing sensitivities to copper. The diatom Phaeodactylum tricornutum was particularly sensitive to copper, with a 72-h IC50 (concentration of copper to inhibit growth rate by 50%) of 8.0 microg Cu L(-1), compared to the green algae Tetraselmis sp. (72-h IC50 47 microg Cu L(-1)) and Dunaliella tertiolecta (72-h IC50 530 microg Cu L(-1)). At these IC50 concentrations, Tetraselmis sp. had much higher intracellular copper (1.97+/-0.01 x 10(-13)g Cu cell(-1)) than P. tricornutum (0.23+/-0.19 x 10(-13)g Cu cell(-1)) and D. tertiolecta (0.59+/-0.05 x 10(-13)g Cu cell(-1)), suggesting that Tetraselmis sp. effectively detoxifies copper within the cell. By contrast, at the same external copper concentration (50 microg L(-1)), D. tertiolecta appears to better exclude copper than Tetraselmis sp. by having a slower copper internalisation rate and lower internal copper concentrations at equivalent extracellular concentrations. The results suggest that the use of internal copper concentrations and net uptake rates alone cannot explain differences in species-sensitivity for different algal species. Model prediction of copper toxicity to marine biota and understanding fundamental differences in species-sensitivity will require, not just an understanding of water quality parameters and copper-cell binding, but also further knowledge of cellular detoxification mechanisms.

Copper-gold nanoparticles: Fabrication, characteristic and application as drug carriers

Energy Technology Data Exchange (ETDEWEB)

Woźniak-Budych, Marta J., E-mail: marta.budych@amu.edu.pl; Langer, Krzysztof; Peplińska, Barbara; Przysiecka, Łucja; Jarek, Marcin; Jarzębski, Maciej; Jurga, Stefan

2016-08-15

In this investigation, the fabrication of porous core/shell nanostructures consisting of copper (core) and copper-gold nanoalloy (shell) for medical applications is presented. As a core triangular-shaped copper nanoparticles were used. The porous bimetallic nanoshell was prepared via galvanic reaction in the presence of oil-in water emulsion. It was proved that porous nanoalloy layer can be prepared at pH 7 and in the presence 0.1% and 0.5% oil-in water emulsion. The porous structure fabrication was mainly determined by volume fraction of hexadecane to acetone in the oil-in water emulsion and Zeta-potential of emulsion droplets (pH of emulsion). The influence of emulsion droplets size before galvanic reaction on porous structure preparation was negligible. It was found that doxorubicin could be easily introduced and released from porous core/shell nanostructures, due to spontaneous adsorption on the copper-gold nanoporous surface. The in vitro test showed that cytotoxic effect was more prominent once the doxorubicin was adsorbed on the porous copper-gold nanocarriers. It was demonstrated, that doxorubicin-loaded copper-gold nanostructures caused inhibition cell proliferation and viability of cancer cells, in a concentration-dependent manner. The results indicates that presented coper-gold nanocarrier have potential to be used in targeted cancer therapy, due to its porous structure and cytotoxic effect in cancer cells. - Highlights: • Porous copper-gold nanostructure as a cytostatic drug carrier was prepared. • Kinetics and thermodynamics of drug adsorption were studied. • DOX-loaded copper-gold nanoparticles showed a pH-controlled release rate. • DOX-loaded copper-gold NPs caused inhibition cell proliferation of cancer cells. • The Cu-Au NPs could serve as a theranostic platform for biomedical applications.

Antimicrobial and bone-forming activity of a copper coated implant in a rabbit model.

Science.gov (United States)

Prinz, Cornelia; Elhensheri, Mohamed; Rychly, Joachim; Neumann, Hans-Georg

2017-08-01

Current strategies in implant technology are directed to generate bioactive implants that are capable to activate the regenerative potential of the surrounding tissue. On the other hand, implant-related infections are a common problem in orthopaedic trauma patients. To meet both challenges, i.e. to generate a bone implant with regenerative and antimicrobial characteristics, we tested the use of copper coated nails for surgical fixation in a rabbit model. Copper acetate was galvanically deposited with a copper load of 1 µg/mm 2 onto a porous oxide layer of Ti6Al4V nails, which were used for the fixation of a tibia fracture, inoculated with bacteria. After implantation of the nail the concentration of copper ions did not increase in blood which indicates that copper released from the implant was locally restricted to the fracture site. After four weeks, analyses of the extracted implants revealed a distinct antimicrobial effect of copper, because copper completely prevented both a weak adhesion and firm attachment of biofilm-forming bacteria on the titanium implant. To evaluate fracture healing, radiographic examination demonstrated an increased callus index in animals with copper coated nails. This result indicates a stimulated bone formation by releasing copper ions. We conclude that the use of implants with a defined load of copper ions enables both prevention of bacterial infection and the stimulation of regenerative processes.

Growth of Cu thin films by the successive ionic layer adsorption and reaction (SILAR) method

International Nuclear Information System (INIS)

Lindroos, S.; Ruuskanen, T.; Ritala, M.; Leskelae, M.

2004-01-01

Copper thin films were grown on reduced indium tin oxide, molybdenum and polymer substrates using successive ionic layer adsorption and reaction (SILAR) method. Copper films were grown sequentially in a controlled way using simple copper salt and basic solution of formaldehyde as precursors. The copper films were polycrystalline with no preferred orientation as characterised by X-ray diffraction. On all substrates, the growth was clearly island growth in the beginning but after the whole surface was covered, the growth was more homogeneous

Effects of Pregnant Leach Solution Temperature on the Permeability of Gravelly Drainage Layer of Heap Leaching Structures

Directory of Open Access Journals (Sweden)

mehdi amini

2013-12-01

Full Text Available In copper heap leaching structures, the ore is leached by an acidic solution. After dissolving the ore mineral, the heap is drained off in the acidic solution using a drainage system (consisting of a network of perforated polyethylene pipes and gravelly drainage layers and is, then, transferred to the leaching plant for copper extraction where the copper is extracted and the remaining solution is dripped over the ore heap for re-leaching. In this process, the reaction between the acidic solution and copper oxide ore is exothermal and the pregnant leach solution (PLS, which is drained off the leaching heap, has a higher temperature than the dripped acidic solution. The PLS temperature variations cause some changes in the viscosity and density which affect the gravelly drainage layer's permeability. In this research, a special permeability measuring system was devised for determining the effects of the PLS temperature variations on the permeability coefficient of the gravelly drainage layer of heap leaching structures. The system, consisting of a thermal acid resistant element and a thermocouple, controls the PLS temperature, which helps measure the permeability coefficient of the gravelly drainage layer. The PLS and gravelly drainage layer of Sarcheshmeh copper mine heap leaching structure No. 1 were used in this study. The permeability coefficient of the gravelly soil was measured against the PLS and pure water at temperatures varying between 3°C to 60°C. Also, the viscosity and density of the PLS and pure water were measured at these temperatures and, using existing theoretical relations, the permeability coefficient of the gravel was computed. A comparison between the experimental and theoretical results revealed a good conformity between the two sets of results. Finally, a case (Taft heap leaching structure, Yazd, Iran was studied and its gravelly drainage layer was designed based on the results of the present research.

Electrochemical behaviour of copper in N,N-dimethylformamide + 0.5 M potassium perchlorate solution

Directory of Open Access Journals (Sweden)

S. MENTUS

2000-09-01

Full Text Available The electrochemical deposition and dissolution of copper in 0.0025 M CuSO4 + N,N-dimethylformamide + 0.5 M KClO4 solution was examined by the rotating disc and potentiodynamic methods. Both platinum and copper were used as working electrodes. A wide polarization range –1 to +2 V vs. SCE, and several temperatures between 25 and 55°C were encompased. The Cu/electrolyte interface was found to be permanently out of equilibrium, as a consequence of the development of a passivating layer. In accordance with the classic theory of a copper electrode in acidified aqueous solutions, the cathodic and anodic Tafel lines of metallic copper define a unique value of the exchange current density, however, their slopes do not correspond to the classic theory.

Effect of chloride ions on the corrosion behavior of low-alloy steel containing copper and antimony in sulfuric acid solution

Science.gov (United States)

Park, Sun-Ah; Kim, Seon-Hong; Yoo, Yun-Ha; Kim, Jung-Gu

2015-05-01

The influence of the addition of HCl on the corrosion behavior of low-alloy steel containing copper and antimony was investigated using electrochemical (potentiodynamic and potentiostatic polarization tests, and electrochemical impedance spectroscopy) and weight loss tests in a 1.6M H2SO4 solution with different concentrations of hydrochloric acid (0.00, 0.08, 0.15 and 0.20 M HCl) at 60 °C. The result showed that the corrosion rate decreased with increasing HCl by the formation of protective layers. SEM, EDS and XPS examinations of the corroded surfaces after the immersion test indicated that the corrosion production layer formed in the solution containing HCl was highly comprised of metallic Cu, Cu chloride and metallic (Fe, Cu, Sb) compounds. The corrosion resistance was improved by the Cu-enriched layer, in which chloride ions are an accelerator for cupric ion reduction during copper deposition. Furthermore, cuprous and antimonious chloride species are complex salts for cuprous ions adsorbed on the surface during copper deposition.

Crystal structure and characterization of a novel layered copper-lithium phosphonate with antiferromagnetic intrachain Cu(II)···Cu(II) interactions

Energy Technology Data Exchange (ETDEWEB)

Abdelbaky, Mohammed S.M. [Departments of Physical and Analytical Chemistry and Organic and Inorganic Chemistry, University of Oviedo-CINN, 33006 Oviedo (Spain); Amghouz, Zakariae [Scientific and Technical Services, University of Oviedo-CINN, 33006 Oviedo (Spain); Department of Materials Science and Metallurgical Engineering, University of Oviedo, Campus Universitario, 33203 Gijón (Spain); Blanco, David Martínez [Scientific and Technical Services, University of Oviedo-CINN, 33006 Oviedo (Spain); García-Granda, Santiago; García, José R. [Departments of Physical and Analytical Chemistry and Organic and Inorganic Chemistry, University of Oviedo-CINN, 33006 Oviedo (Spain)

2017-04-15

Novel metal phosphonate [CuLi(PPA)] [H{sub 3}PPA=3-phosphonopropionic acid] was synthesized hydrothermally and characterized by single-crystal X-ray diffraction, powder X-ray diffraction, scanning electron microscopy, infrared spectroscopy, and thermogravimetric analysis. It crystallizes in the space group C2/c, with cell parameters a=21.617(2) Å, b=4.9269(2) Å, c=14.342(1) Å, β=132.3(2)°, and Z=8. Its framework is built up from a main trimer, acting as a secondary building unit (SBU), which is formed by vertex-shared between two (LiO{sub 4}) and one (Cu(1)O{sub 4}) polyhedra. These units repeat along b-axis forming infinite inorganic chains, these chains are in turn cross-linked by corner sharing with (Cu(2)O{sub 4}) polyhedra to produce inorganic layers lying in the bc-plane. The neighboring layers are connected through the PPA ligand, leading to a 3D pillared-layered structure. The topological analysis reveals that the compound exhibits 3,4,10-c net. Finally, magnetic susceptibility measurement of this compound over the temperature range of 2–300 K reveals the occurrence of weak antiferromagnetic intrachain interactions. - Graphical abstract: Hydrothermal synthesis and structural characterization of a novel lithium-copper phosphonate, formulated as [CuLi(PPA)] (H{sub 3}PPA=3-phosphonopropionic acid), have been reported. This compound has a 3D pillared-layered structure with 3,4,10-c net topology. The magnetic susceptibility data over the temperature range of 2–300 K reveals the occurrence of weak antiferromagnetic interactions. - Highlights: • Novel metal phosphonate, [CuLi(PPA)] (1), has been synthesized and characterized. • Compound 1 has a 3D pillared-layered structure with 3,4,10-c net topology. • Magnetic susceptibility data reveals the occurrence of weak antiferromagnetic interactions.

Multi-layered Chalcogenides with potential for magnetism and superconductivity

Energy Technology Data Exchange (ETDEWEB)

Li, Li, E-mail: lil2@ornl.gov [Materials Science & Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Parker, David S. [Materials Science & Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Cruz, Clarina R. dela [Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Sefat, Athena S., E-mail: sefata@ornl.gov [Materials Science & Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States)

2016-12-15

Highlights: • A comprehensive study on multi-layered thallium copper chalcogenides TlCu{sub 2n}Ch{sub n+1}. • All the TlCu{sub 2n}Ch{sub n+1} exhibit metallic behaviors with no long-range magnetism. • Calculations suggest a lack of Fermi-level spectral weight for magnetic instability. • Our results suggest a likelihood of magnetism for multiple structural layers with Fe. - Abstract: Layered thallium copper chalcogenides can form single, double, or triple layers of Cu–Ch separated by Tl sheets. Here we report on the preparation and properties of Tl-based materials of TlCu{sub 2}Se{sub 2}, TlCu{sub 4}S{sub 3}, TlCu{sub 4}Se{sub 3} and TlCu{sub 6}S{sub 4}. Having no long-range magnetism for these materials is quite surprising considering the possibilities of inter- and intra-layer exchange interactions through Cu 3d, and we measure by magnetic susceptibility and confirm by neutron diffraction. First principles density-functional theory calculations for both the single-layer TlCu{sub 2}Se{sub 2} (isostructural to the ‘122’ iron-based superconductors) and the double-layer TlCu{sub 4}Se{sub 3} suggest a lack of Fermi-level spectral weight that is needed to drive a magnetic or superconducting instability. However, for multiple structural layers with Fe, there is much greater likelihood for magnetism and superconductivity.

Study of underpotential deposited Cu layers on Pt(111) and their stability against CO and CO2 in perchloric acid

DEFF Research Database (Denmark)

Schlaup, Christian Georg; Horch, Sebastian

2013-01-01

The underpotential deposition (UPD) of copper on a Pt(111) electrode and the influence of gas coadsorbates, i.e. CO and CO2, on the thus deposited copper layer were studied in a 0.1 M HClO4 electrolyte by means of EC-STM. By UPD, an atomically flat Cu layer is formed, which exhibits a pseudomorph...

Microstructure in electrodeposited copper layers; the role of the substrate

DEFF Research Database (Denmark)

Rasmussen, Anette Alsted; Jensen, Jens Dahl; Horsewell, Andy

2001-01-01

-crystalline Ni-P layer. The evolutions of surface topography, morphology and crystallographic texture in the layers were investigated with scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction analysis, respectively. Distinct surface topographies were observed for Cu...

Multilevel Dual Damascene copper interconnections

Science.gov (United States)

Lakshminarayanan, S.

C, 500oC and 600oC for Ti, TiN and Ta barriers respectively. Via resistivity on the order of 10-9/ /Omegacm2 was measured for Cu/Ta/Cu interfaces and no degradation in the via resistance was observed upto 600oC on the 2 μm and 3 μm wide contact windows. Characterization of diode leakage and subthreshold currents of CMOS transistors fabricated with Ta adhesion layers, showed the failure of the Ta barrier at 450oC. Despite the good barrier performance of the CVD TiN films, obtaining low contact resistivity may be a concern. The potential use of Cu-Mg alloy as the backend metallization has also been studied. Fully encapsulated wiring has been fabricated by causing the Mg to out- diffuse towards the Cu/SiO2 interfaces and the free copper surface. The inter-connects exhibited good stability and oxidation resistance, but via resistances were extremely high, probably due to the presence of insulating films like MgO or MgF2 at the interface between the two metal levels. It may be possible to decrease the via resistance to values comparable to Cu/Ta/Cu by altering the process flow and using a suitable via clean. When used at the contact level, undesirable interaction with the CoSi2 film was observed at temperatures as low as 350oC. Another problem was the high contact resistance at the Cu-Mg/CoSi2 interface. Hence the use of this alloy as a contact fill material is not feasible at this time. An additional barrier layer may be required between the Cu-Mg and CoSi2 films to protect the integrity of the silicide and provide low contact resistance.

Improvement of the photovoltaic parameters of perovskite solar cells using a reduced-graphene-oxide-modified titania layer and soluble copper phthalocyanine as a hole transporter.

Science.gov (United States)

Nouri, Esmaiel; Mohammadi, Mohammad Reza; Xu, Zong-Xiang; Dracopoulos, Vassilios; Lianos, Panagiotis

2018-01-24

Functional perovskite solar cells can be made by using a simple, inexpensive and stable soluble tetra-n-butyl-substituted copper phthalocyanine (CuBuPc) as a hole transporter. In the present study, TiO 2 /reduced graphene oxide (T/RGO) hybrids were synthesized via an in situ solvothermal process and used as electron acceptor/transport mediators in mesoscopic perovskite solar cells based on soluble CuBuPc as a hole transporter and on graphene oxide (GO) as a buffer layer. The impact of the RGO content on the optoelectronic properties of T/RGO hybrids and on the solar cell performance was studied, suggesting improved electron transport characteristics and photovoltaic parameters. An enhanced electron lifetime and recombination resistance led to an increase in the short circuit current density, open circuit voltage and fill factor. The device based on a T/RGO mesoporous layer with an optimal RGO content of 0.2 wt% showed 22% higher photoconversion efficiency and higher stability compared with pristine TiO 2 -based devices.

Growth of cadmium oxide whiskers on cadmium sulphide single crystals with copper as growth activator

Energy Technology Data Exchange (ETDEWEB)

Koparanova, N.; Simov, S. (Bylgarska Akademiya na Naukite, Sofia. Inst. po Fizika na Tvyrdoto Tyalo); Genchev, D. (Bylgarska Akademiya na Naukite, Sofia. Inst. za Yadrena Izsledvaniya i Yadrena Energetika); Metchenov, G. (Research Inst. of Criminalistics and Criminology, Sofia (Bulgaria))

1985-02-01

Some results on the growth and morphology of cadmium oxide whiskers, obtained on cadmium sulphide single crystals with copper as a growth activator, are presented in this work. Cadmium oxide whiskers have been obtained on brace 112-bar0 brace faces of cadmium sulphide plates with a copper layer deposited in advance. The whiskers grew during the annealing of the plates in a weak stream of technically pure argon at temperatures 670 to 730 deg C for 15 min to 3.5 h. Details about the procedure have been given elsewhere. The composition and morphology of the whiskers have been studied by an X-ray microanalyser JEOL 35 DDS and a scanning electron microscope JEOL, JSM 35. The optical microscopic observations have shown that after annealing, a gray-black granular layer is formed on the cadmium sulphide single crystals and this layer can easily be separated from the crystal substrate. Under the granular layer the crystal is heavily damaged. The whiskers grow on the granular layer and they are coloured yellow-brown or red-brown. The maximum whisker length attains several hundreds of micrometres and in some cases up to 1 mm or more.

Growth of cadmium oxide whiskers on cadmium sulphide single crystals with copper as growth activator

International Nuclear Information System (INIS)

Koparanova, N.; Simov, S.

1985-01-01

Some results on the growth and morphology of cadmium oxide whiskers, obtained on cadmium sulphide single crystals with copper as a growth activator, are presented in this work. Cadmium oxide whiskers have been obtained on brace 112-bar0 brace faces of cadmium sulphide plates with a copper layer deposited in advance. The whiskers grew during the annealing of the plates in a weak stream of technically pure argon at temperatures 670 to 730 deg C for 15 min to 3.5 h. Details about the procedure have been given elsewhere. The composition and morphology of the whiskers have been studied by an X-ray microanalyser JEOL 35 DDS and a scanning electron microscope JEOL, JSM 35. The optical microscopic observations have shown that after annealing, a gray-black granular layer is formed on the cadmium sulphide single crystals and this layer can easily be separated from the crystal substrate. Under the granular layer the crystal is heavily damaged. The whiskers grow on the granular layer and they are coloured yellow-brown or red-brown. The maximum whisker length attains several hundreds of micrometres and in some cases up to 1 mm or more. (author)

Electrical conduction in composites containing copper core-copper

Indian Academy of Sciences (India)

Composites of nanometre-sized copper core-copper oxide shell with diameters in the range 6.1 to 7.3 nm dispersed in a silica gel were synthesised by a technique comprising reduction followed by oxidation of a suitably chosen precursor gel. The hot pressed gel powders mixed with nanometre-sized copper particles ...

Paintings on copper by the Flemish artist Frans Francken II: PIXE characterization by external microbeam

International Nuclear Information System (INIS)

Corregidor, V.; Oliveira, A.R.; Rodrigues, P.A.; Alves, L.C.

2015-01-01

Resorting to an external proton microbeam, PIXE analyses of three oil paintings on copper support dated from the XVII century and attributed to the Flemish artist Frans Francken II, were undertaken. The present work aims to contribute to the compositional study of the painting materials employed by XVII century artists that exploited copper as a support for oil painting, and specifically the materials used by Francken’s workshop, particularly copper plates. Because of the low thickness of the pictorial layers of this type of paintings and its non-destructive character, PIXE is the ideal technique to study the elemental composition of the paintings. Several spots in each painting were chosen for analysis in order to cover almost all the pigments used in the colour palette. Lead and calcium were detected in practically every analysed regions, probably related to the presence of lead white and chalk, usually used as ground layer on copper paintings. Small quantities of gold were also detected, which is present in many of this artist’s works to embellish some details of the representations. Also this work reports the first application of the external proton microbeam set-up available at CTN/IST in Portugal for the characterization of oil paintings

High-speed collision of copper nanoparticle with aluminum surface: Molecular dynamics simulation

Energy Technology Data Exchange (ETDEWEB)

Pogorelko, Victor V., E-mail: vik_ko83@mail.ru [Chelyabinsk State University, Bratiev Kashirinykh 129, 454001 Chelyabinsk (Russian Federation); South Ural State University (National Research University), Lenin Prospect 76, 454080 Chelyabinsk (Russian Federation); Mayer, Alexander E., E-mail: mayer@csu.ru [Chelyabinsk State University, Bratiev Kashirinykh 129, 454001 Chelyabinsk (Russian Federation); South Ural State University (National Research University), Lenin Prospect 76, 454080 Chelyabinsk (Russian Federation); Krasnikov, Vasiliy S., E-mail: vas.krasnikov@gmail.com [Chelyabinsk State University, Bratiev Kashirinykh 129, 454001 Chelyabinsk (Russian Federation); South Ural State University (National Research University), Lenin Prospect 76, 454080 Chelyabinsk (Russian Federation)

2016-12-30

Highlights: • High-speed nanoparticle impact induces shock waves and intensive plastic deformation. • Lattice orientation strongly influences on the deformation degree. • Plastic deformation goes through nucleation, growth and separation of semi-loops. • Medium impact energy and elevated temperature are optimal for high-quality coating. • High impact velocity and room temperature lead to plastic deformation and coating. - Abstract: We investigate the effect of the high-speed collision of copper nanoparticles with aluminum surface by means of molecular dynamic simulations. Studied diameter of nanoparticles is varied within the range 7.2–22 nm and the velocity of impact is equal to 500 or 1000 m/s. Dislocation analysis shows that a large quantity of dislocations is formed within the impact area. Overall length of dislocations is determined, first of all, by the impact velocity and by the size of incident copper nanoparticle, in other words, by the kinetic energy of the nanoparticle. Dislocations occupy the total volume of the impacted aluminum single crystal layer (40.5 nm in thickness) in the form of intertwined structure in the case of large kinetic energy of the incident nanoparticle. Decrease in the initial kinetic energy or increase in the layer thickness lead to restriction of the penetration depth of the dislocation net; formation of separate dislocation loops is observed in this case. Increase in the initial system temperature slightly raises the dislocation density inside the bombarded layer and considerably decreases the dislocation density inside the nanoparticle. The temperature increase also leads to a deeper penetration of the copper atoms inside the aluminum. Additional molecular dynamic simulations show that the deposited particles demonstrate a very good adhesion even in the case of the considered relatively large nanoparticles. Medium energy of the nanoparticles corresponding to velocity of about 500 m/s and elevated temperature of the

High-speed collision of copper nanoparticle with aluminum surface: Molecular dynamics simulation

International Nuclear Information System (INIS)

Pogorelko, Victor V.; Mayer, Alexander E.; Krasnikov, Vasiliy S.

2016-01-01

Highlights: • High-speed nanoparticle impact induces shock waves and intensive plastic deformation. • Lattice orientation strongly influences on the deformation degree. • Plastic deformation goes through nucleation, growth and separation of semi-loops. • Medium impact energy and elevated temperature are optimal for high-quality coating. • High impact velocity and room temperature lead to plastic deformation and coating. - Abstract: We investigate the effect of the high-speed collision of copper nanoparticles with aluminum surface by means of molecular dynamic simulations. Studied diameter of nanoparticles is varied within the range 7.2–22 nm and the velocity of impact is equal to 500 or 1000 m/s. Dislocation analysis shows that a large quantity of dislocations is formed within the impact area. Overall length of dislocations is determined, first of all, by the impact velocity and by the size of incident copper nanoparticle, in other words, by the kinetic energy of the nanoparticle. Dislocations occupy the total volume of the impacted aluminum single crystal layer (40.5 nm in thickness) in the form of intertwined structure in the case of large kinetic energy of the incident nanoparticle. Decrease in the initial kinetic energy or increase in the layer thickness lead to restriction of the penetration depth of the dislocation net; formation of separate dislocation loops is observed in this case. Increase in the initial system temperature slightly raises the dislocation density inside the bombarded layer and considerably decreases the dislocation density inside the nanoparticle. The temperature increase also leads to a deeper penetration of the copper atoms inside the aluminum. Additional molecular dynamic simulations show that the deposited particles demonstrate a very good adhesion even in the case of the considered relatively large nanoparticles. Medium energy of the nanoparticles corresponding to velocity of about 500 m/s and elevated temperature of the

Hindered rotation of a copper phthalocyanine molecule on C60 : Experiments and molecular mechanics calculations

NARCIS (Netherlands)

Fendrich, M.; Wagner, Th.; Stöhr, M.; Möller, R.

2006-01-01

If copper phthalocyanine (CuPc) molecules are deposited on a Au(111) surface covered with a monolayer of C60, the molecules are found to adsorb individually onto the close-packed layer of C60. As the adsorption site of the CuPc is not symmetric with respect to the underlying C60 layer, the CuPc

Reagent conditions of the flotation of copper, copper - molybdenum and copper -zinc ores in foreing countries

International Nuclear Information System (INIS)

Nevaeva, L.M.

1983-01-01

Reagents-collectors and frothers, used abroad in reagent regimes of flotation of copper, copper-molybdenum and copper zinc ores, have been considered. Xanthogenates, aerofloats, xanthogenformiates, thionocarbamates are mainly used as reagents-collectors. Methylizobutylcarbinol and Daufros are used as reagents-frothers

Charge Transfer Properties Through Graphene Layers in Gas Detectors

CERN Document Server

Thuiner, P.; Jackman, R.B.; Müller, H.; Nguyen, T.T.; Oliveri, E.; Pfeiffer, D.; Resnati, F.; Ropelewski, L.; Smith, J.A.; van Stenis, M.; Veenhof, R.

2016-01-01

Graphene is a single layer of carbon atoms arranged in a honeycomb lattice with remarkable mechanical, electrical and optical properties. For the first time graphene layers suspended on copper meshes were installed into a gas detector equipped with a gaseous electron multiplier. Measurements of low energy electron and ion transfer through graphene were conducted. In this paper we describe the sample preparation for suspended graphene layers, the testing procedures and we discuss the preliminary results followed by a prospect of further applications.

Copper recovery in a bench-scale carrier facilitated tubular supported liquid membrane system

Directory of Open Access Journals (Sweden)

Makaka S.

2010-01-01

Full Text Available The extraction of copper ions in a tubular supported liquid membrane using LIX 984NC as a mobile carrier was studied, evaluating the effect of the feed characteristics (flowrate, density, viscosity on the feedside laminar layer of the membrane. A vertical countercurrent, double pipe perspex benchscale reactor consisting of a single hydrophobic PVDF tubular membrane mounted inside was used in all test work. The membrane was impregnated with LIX 984NC and became the support for this organic transport medium. Dilute Copper solution passed through the centre pipe and sulphuric acid as strippant passed through the shell side. Copper was successfully transported from the feedside to the stripside and from the data obtained, a relationship between Schmidt, Reynolds and Sherwood number was achieved of.

Effect of metallic coating on the properties of copper-silicon carbide composites

Science.gov (United States)

Chmielewski, M.; Pietrzak, K.; Teodorczyk, M.; Nosewicz, S.; Jarząbek, D.; Zybała, R.; Bazarnik, P.; Lewandowska, M.; Strojny-Nędza, A.

2017-11-01

In the presented paper a coating of SiC particles with a metallic layer was used to prepare copper matrix composite materials. The role of the layer was to protect the silicon carbide from decomposition and dissolution of silicon in the copper matrix during the sintering process. The SiC particles were covered by chromium, tungsten and titanium using Plasma Vapour Deposition method. After powder mixing of components, the final densification process via Spark Plasma Sintering (SPS) method at temperature 950 °C was provided. The almost fully dense materials were obtained (>97.5%). The microstructure of obtained composites was studied using scanning electron microscopy as well as transmission electron microscopy. The microstructural analysis of composites confirmed that regardless of the type of deposited material, there is no evidence for decomposition process of silicon carbide in copper. In order to measure the strength of the interface between ceramic particles and the metal matrix, the micro tensile tests have been performed. Furthermore, thermal diffusivity was measured with the use of the laser pulse technique. In the context of performed studies, the tungsten coating seems to be the most promising solution for heat sink application. Compared to pure composites without metallic layer, Cu-SiC with W coating indicate the higher tensile strength and thermal diffusitivy, irrespective of an amount of SiC reinforcement. The improvement of the composite properties is related to advantageous condition of Cu-SiC interface characterized by well homogenity and low porosity, as well as individual properties of the tungsten coating material.

Phosphate ions as inhibiting agents for copper corrosion in chlorinated tap water

Energy Technology Data Exchange (ETDEWEB)

Yohai, L. [División Electroquímica y Corrosión, INTEMA, CONICET, UNMdP, Juan B. Justo 4302, B7608FDQ Mar del Plata (Argentina); Schreiner, W.H. [Laboratório de Superfícies e Interfases, Departamento de Física, Universidade Federal do Paraná, 81531-990 Curitiba, PR (Brazil); Vázquez, M., E-mail: mvazquez@fi.mdp.edu.ar [División Electroquímica y Corrosión, INTEMA, CONICET, UNMdP, Juan B. Justo 4302, B7608FDQ Mar del Plata (Argentina); Valcarce, M.B. [División Electroquímica y Corrosión, INTEMA, CONICET, UNMdP, Juan B. Justo 4302, B7608FDQ Mar del Plata (Argentina)

2013-05-15

PO{sub 4}{sup 3−} ions as corrosion inhibitor were investigated on copper in tap water in the presence of NaClO. The inhibitor was evaluated by electrochemical techniques and weight loss tests. Raman spectroscopy and X-ray photoelectron spectroscopy were used to study the passive layer. In inhibited tap water, the passive layer is thick and compact if NaClO is present. Weight-loss tests showed the inhibition of uniform dissolution and no pitting attack. When adding NaClO, Cu{sub 3}(PO{sub 4}){sub 2} is incorporated to the passive film. Thus, phosphate ions are effective as inhibitors for copper in tap water, even when using high dosages of biocides. - Highlights: ► Changes in the copper corrosion after adding phosphate to tap water were analyzed. ► When NaClO and phosphates are present, Cu{sub 3}(PO{sub 4}){sub 2} participates of the surface film. ► In the absence of biocide the surface film contains a mixture of Cu{sub 2}O, CuO and Cu(OH){sub 2}. ► PO{sub 4}{sup 3−} is an effective inhibitor for Cu in tap water containing high NaClO dosages.

Layer-by-layer deposition of superconducting Sr-Ca-Cu-O films by the spray pyrolysis technique

International Nuclear Information System (INIS)

Pawar, S.H.; Pawaskar, P.N.; Ubale, M.J.; Kulkarni, S.B.

1995-01-01

Layer-by-layer deposition of Sr-Ca-Cu-O films has been carried out using the spray pyrolysis technique. Reagent-grade nitrates of strontium, calcium and copper were used to prepare starting solutions for spray pyrolysis. A two-step procedure was used for every layer of the constituents in the sequence Sr-Cu-Ca-Cu-Sr: first, deposition onto silver substrate at 350 C, then firing at T≥450 C, both at atmospheric pressure. The films were 2-3 μm thick and showed adequate adhesion to the substrate. The films were then characterised by studying their electron micrographs, X-ray diffraction patterns and electrical resistivity. The films showed superconductivity below 104 K. ((orig.))

Selective tuning of magnetization dynamics damping in Tb- and Nd-doped permalloy ultrathin films by adjacent copper nanolayers

Energy Technology Data Exchange (ETDEWEB)

Zhang, Dong, E-mail: physzd@yahoo.com [School of Physics Science and Information Engineering, Key Lab. of Communication Science and Technology of Shandong Province, Liaocheng University, Liaocheng 252059 (China); Physics Department, Southeast University, Nanjing 211189 (China); Yue, Jinjin; Jiang, Sheng [Physics Department, Southeast University, Nanjing 211189 (China); Zhai, Ya, E-mail: yazhai@seu.edu.cn [Physics Department, Southeast University, Nanjing 211189 (China); National Laboratory of Solid Microstructures, Nanjing University, Nanjing 210093 (China); Du, Jun; Zhai, Hongru [National Laboratory of Solid Microstructures, Nanjing University, Nanjing 210093 (China)

2016-07-05

The mechanism of angular dependence of ferromagnetic resonance linewidth of dilute Tb and Nd doping in permalloy thin films with various thicknesses of adjacent copper layer are investigated by experimental approach and theoretical fitting by considering the contributions from intrinsic spin-orbit coupling, inhomogeneous broadening and two-magnon scattering. The results show that the damping coefficient α, by intrinsic contribution extracted from ferromagnetic resonance linewidth, increases from 0.0153 to 0.0218 for NiFe–Nd films and from 0.0193 to 0.0261 for NiFe–Tb films resulting from the spin pumping effect at the interface of NiFe–Nd(or Tb)/Cu as the thickness of copper layer increases from 1 nm to 15 nm. The surface magnetic anisotropy constant K{sub 1} is obtained and shows an decreasing trend from positive to negative, which implies that the copper layer could reduce the surface perpendicular anisotropy. The fitting spin mixed conductivity is (2.72 ± 0.18) × 10{sup 15} cm{sup −2} at NiFe–Tb/Cu interface and (2.4 ± 0.2) × 10{sup 15} cm{sup −2} at Cu/NiFe–Nd interface, respectively. - Highlights: • The thickness of Cu buffer layer affects the surface perpendicular anisotropy of FM layer. • The interface roughness could be investigated by using FMR linewidth. • The damping coefficient is enhanced by spin-pumping effect.

Structural changes in a copper alloy due to helium implantation

International Nuclear Information System (INIS)

Moreno, D.; Eliezer, D.

1996-01-01

The most suitable nuclear fusion reaction for energy production occurs between the two heavy hydrogen isotopes, deuterium and tritium. Structural materials in fusion reactors will be exposed to helium implantation over a broad range of energies. The deformation and partial exfoliation of surface layers due to hydrogen isotopes and helium contribute to the total erosion of the first wall. For this reason, one of the most important criteria in the choice of materials for the first wall of fusion reactors is the material's damage resistance. Recent advances in developing nuclear fusion reactors reveal that efficient heat removal from plasma-facing components is very important. Copper and copper alloys are considered an attractive choice for transporting such a high heat flux without thermal damage as they have high thermal conductivity. In the present study the authors report on the structural changes in a copper alloy, due to the helium implantation on the very near surface area, observed by transmission electron microscopy

Improving Beneficiation of Copper and Iron from Copper Slag by Modifying the Molten Copper Slag

Directory of Open Access Journals (Sweden)

Zhengqi Guo

2016-04-01

Full Text Available In the paper, a new technology was developed to improve the beneficiation of copper and iron components from copper slag, by modifying the molten slag to promote the mineralization of valuable minerals and to induce the growth of mineral grains. Various parameters, including binary basicity, dosage of compound additive, modification temperature, cooling rate and the end point temperature of slow cooling were investigated. Meanwhile, optical microscope, scanning electron microscope and energy dispersive spectrometer (SEM-EDS was employed to determine the mineralogy of the modified and unmodified slag, as well as to reveal the mechanisms of enhancing beneficiation. The results show that under the proper conditions, the copper grade of rougher copper concentrate was increased from 6.43% to 11.04%, iron recovery of magnetic separation was increased significantly from 32.40% to 63.26%, and other evaluation indexes were changed slightly, in comparison with unmodified copper slag. Moreover, matte and magnetite grains in the modified slag aggregated together and grew obviously to the mean size of over 50 μm, resulting in an improvement of beneficiation of copper and iron.

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

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 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 color...

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

Science.gov (United States)

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 and...

Current Status and Future Prospects of Copper Oxide Heterojunction Solar Cells.

Science.gov (United States)

Wong, Terence K S; Zhuk, Siarhei; Masudy-Panah, Saeid; Dalapati, Goutam K

2016-04-07

The current state of thin film heterojunction solar cells based on cuprous oxide (Cu₂O), cupric oxide (CuO) and copper (III) oxide (Cu₄O₃) is reviewed. These p-type semiconducting oxides prepared by Cu oxidation, sputtering or electrochemical deposition are non-toxic, sustainable photovoltaic materials with application potential for solar electricity. However, defects at the copper oxide heterojunction and film quality are still major constraining factors for achieving high power conversion efficiency, η. Amongst the Cu₂O heterojunction devices, a maximum η of 6.1% has been obtained by using pulsed laser deposition (PLD) of Al x Ga 1- x O onto thermal Cu₂O doped with Na. The performance of CuO/n-Si heterojunction solar cells formed by magnetron sputtering of CuO is presently limited by both native oxide and Cu rich copper oxide layers at the heterointerface. These interfacial layers can be reduced by using a two-step sputtering process. A high η of 2.88% for CuO heterojunction solar cells has been achieved by incorporation of mixed phase CuO/Cu₂O nanopowder. CuO/Cu₂O heterojunction solar cells fabricated by electrodeposition and electrochemical doping has a maximum efficiency of 0.64% after surface defect passivation and annealing. Finally, early stage study of Cu₄O₃/GaN deposited on sapphire substrate has shown a photovoltaic effect and an η of ~10 -2 %.

Multilayer TiC/TiN diffusion barrier films for copper

International Nuclear Information System (INIS)

Yoganand, S.N.; Raghuveer, M.S.; Jagannadham, K.; Wu, L.; Karoui, A.; Rozgonyi, G.

2002-01-01

TiC/TiN thin films deposited by reactive magnetron sputtering on Si (100) substrates were investigated by transmission electron microscopy for microstructure and by deep level transient spectroscopy (DLTS) for diffusion barrier against copper. TiN thin films deposited on Si substrates at a substrate temperature of 600 deg. C were textured, and TiC thin films deposited at the same temperature were polycrystalline. TiC/TiN multilayer films also showed the same characteristics with the formation of an additional interaction layer. The diffusion barrier characteristics of the TiC/TiN/Si were determined by DLTS and the results showed that the films completely prevented diffusion of copper into Si

Multi-layer SiC ceramics/Mo joints brazed using high-temperature solders

International Nuclear Information System (INIS)

Olesinska, W.; Kesik, J.

2003-01-01

The paper presents the results of studies on joining SiC ceramics with molybdenum, with the ceramic surface being activated by titanium, chromium or copper. Titanium or chromium were deposited by the sputtering technique, and copper - by the electro-chemical method. The microstructures of the SiC/Mo joints brazed with the CuMn13Ni3 solder and copper in a nitrogen atmosphere were examined and the results discussed. The joints, in which the ceramic surface was activated in addition with chromium, do not contain mechanical defects caused by the joining process, and the ceramic surface is covered with a continuous layer of the solder. A phase analysis of the interface surface identified an MeSiC phase. The mechanical strength of the joints in which the ceramic surface was modified by the Ti, Cr and Cu layers was markedly greater than that of the joints brazed directly to the uncoated ceramics with the use of active solders. (author)

Mineral formation on metallic copper in a `future repository site environment`

Energy Technology Data Exchange (ETDEWEB)

Amcoff, Oe; Holenyi, K

1996-04-01

Since reducing conditions are expected much effort has been concentrated on Cu-sulfides and CuFe-sulfides. However, oxidizing conditions are also discussed. A list of copper minerals are included. It is concluded that mineral formation and mineral transitions on the copper canister surface will be governed by kinetics and metastabilities rather than by stability relations. The sulfides formed are less likely to form a passivating layer, and the rate of sulfide growth will probably be governed by the rate of transport of reacting species to the canister surface. A series of tests are recommended, in an environment resembling the initial repository site conditions. 82 refs, 8 figs.

Mineral formation on metallic copper in a 'future repository site environment'

International Nuclear Information System (INIS)

Amcoff, Oe.; Holenyi, K.

1996-04-01

Since reducing conditions are expected much effort has been concentrated on Cu-sulfides and CuFe-sulfides. However, oxidizing conditions are also discussed. A list of copper minerals are included. It is concluded that mineral formation and mineral transitions on the copper canister surface will be governed by kinetics and metastabilities rather than by stability relations. The sulfides formed are less likely to form a passivating layer, and the rate of sulfide growth will probably be governed by the rate of transport of reacting species to the canister surface. A series of tests are recommended, in an environment resembling the initial repository site conditions. 82 refs, 8 figs

Layer-by-layer assembled highly absorbing hundred-layer films containing a phthalocyanine dye: Fabrication and photosensibilization by thermal treatment

International Nuclear Information System (INIS)

Sergeeva, Alena S.; Volkova, Elena K.; Bratashov, Daniil N.; Shishkin, Mikhail I.; Atkin, Vsevolod S.; Markin, Aleksey V.; Skaptsov, Aleksandr A.; Volodkin, Dmitry V.; Gorin, Dmitry A.

2015-01-01

Highly absorbing hundred-layer films based on poly(diallyldimethylammonium chloride) (PDADMAC) of various molecular weights and on sulfonated copper phthalocyanine (CuPcTs) were prepared using layer-by-layer assembly. The multilayer films grew linearly up to 54 bilayers, indicating that the same amount of CuPcTs was adsorbed at each deposition step. This amount, however, was dependent on the molecular weight of PDADMAC in the range 100-500 kDa: the higher the molecular weight, the more CuPcTs molecules were adsorbed. This can be explained by the larger surface charge number density specific to longer polymer chains. Domains of pure PDADMAC and of the PDADMAC/CuPcTs complex were formed in the films during the assembly. Uniform distribution of CuPcTs over the films could be achieved by thermal treatment, leading to an α → β phase transition in phthalocyanine at 300 °C. Annealing caused changes in the film absorbance spectra, resulting in a 30-nm red shift of the peak maxima and in a strong (up to 62%) decrease in optical density. Thermogravimetric analysis revealed thermodegradation of PDADMAC during annealing above 270 °C, giving rise to micrometer-sized cracks within the films, as evidenced by scanning electron microscopy. - Highlights: • The films exhibit the linear dependence of the adsorption on the bilayer number varied from 2 until 54. • Polyelectrolyte of the highest MW shows the maximal adsorption of copper phthalocyanine molecules. • Annealing of the films causes a red-shift of the maxima in the absorbance spectra. • Cracks and micropores emerged in the multilayer films during the annealing

Influence of branched quaternary ammonium surfactant molecules as levelers for copper electroplating from acidic sulfate bath

International Nuclear Information System (INIS)

Wang, An-yin; Chen, Biao; Fang, Lei; Yu, Jian-jun; Wang, Li-min

2013-01-01

A family of branched quaternary ammonium surfactants (compounds 1a–1c) with different carbon chains were synthesized for levelers applied in copper electroplating. Their inhibitory actions on copper electroplating were characterized by cyclic voltammetry (CV). Compound 1b, as representative structure type, was tested by means of different electrochemical methods including CV, polarization curve and electrochemical impedance spectroscopy (EIS) with different concentrations. The interaction between compound 1b and copper surface was investigated using atomic force microscope (AFM) and X-ray photoelectron spectra (XPS). The results indicated that our newly synthesized compounds, particular 1b, were effective levelers used for copper electroplating. Compound 1b could adsorb on copper surface to form an adsorption layer. The adsorption behavior of compound 1b on copper surface indicated that compound 1b could inhibit the copper electrodeposition, which provided favorable conditions used as a leveler. Moreover, the addition of compound 1b could increase the cathodic polarization, which was attributed to the adsorption of compound 1b during copper electroplating process. In addition, various surface morphologies and crystalline orientation of the plated copper films caused by different concentrations of compound 1b were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD) respectively. Effects of compound 1b on refining the grain size and changing the preferential orientation of the plated copper films were exhibited

Evaluation of planarization performance for a novel alkaline copper slurry under a low abrasive concentration

International Nuclear Information System (INIS)

Jiang Mengting; Liu Yuling; Yuan Haobo; Chen Guodong; Liu Weijuan

2014-01-01

A novel alkaline copper slurry that possesses a relatively high planarization performance is investigated under a low abrasive concentration. Based on the action mechanism of CMP, the feasibility of using one type of slurry in copper bulk elimination process and residual copper elimination process, with different process parameters, was analyzed. In addition, we investigated the regular change of abrasive concentration effect on copper and tantalum removal rate and within wafer non-uniformity (WIWNU) in CMP process. When the abrasive concentration is 3 wt%, in bulk elimination process, the copper removal rate achieves 6125 Å/min, while WIWNU is 3.5%, simultaneously. In residual copper elimination process, the copper removal rate is approximately 2700 Å/min, while WIWNU is 2.8%. Nevertheless, the tantalum removal rate is 0 Å/min, which indicates that barrier layer isn't eliminated in residual copper elimination process. The planarization experimental results show that an excellent planarization performance is obtained with a relatively high copper removal rate in bulk elimination process. Meanwhile, after residual copper elimination process, the dishing value increased inconspicuously, in a controllable range, and the wafer surface roughness is only 0.326 nm (sq < 1 nm) after polishing. By comparison, the planarization performance and surface quality of alkaline slurry show almost no major differences with two kinds of commercial acid slurries after polishing. All experimental results are conducive to research and improvement of alkaline slurry in the future. (semiconductor technology)

Bismuth oxychloride homogeneous phasejunction BiOCl/Bi12O17Cl2 with unselectively efficient photocatalytic activity and mechanism insight

Science.gov (United States)

Hao, Lin; Huang, Hongwei; Guo, Yuxi; Du, Xin; Zhang, Yihe

2017-10-01

Fabrication of homo/hetero-junctions by coupling of wide-band gap semiconductor and narrow-band gap semiconductor is desirable as they can achieve a decent balance between photoabsorption and photo-redox ability. Herein, a n-n type bismuth oxychloride homogeneous phasejunction BiOCl/Bi12O17Cl2 was developed by facilely manipulating the basicity in a one-pot hydrothermal process. Compared with BiOCl which only responds to UV light, the photo-responsive range is remarkably extended to visible region. The BiOCl/Bi12O17Cl2 phasejunctions show much higher photocatalytic activity than the single BiOCl and Bi12O17Cl2 toward degradation of methyl orange (MO) under simulated solar light. In particular, it presented a high photo-oxidation ability in degrading diverse industrial contaminants including 2,4-dichlorophenol (2,4-DCP), phenol, bisphenol A (BPA) and tetracycline hydrochloride. Based on a series of photoelectrochemical and photoluminescence measurements, the fortified photocatalytic performance of BiOCl/Bi12O17Cl2 phasejunctions was manifested to be attributed to the efficient separation and transfer efficiencies of photoinduced electron-hole pairs because of the junctional interface formed between BiOCl and Bi12O17Cl2. The study may not only furnish a high-effective photocatalyst in the application of environment purification, but also pave a path to fabricate agnate phase-junctional photocatalyst.

Nickel, copper and cobalt coalescence in copper cliff converter slag

Directory of Open Access Journals (Sweden)

Wolf A.

2016-01-01

Full Text Available The aim of this investigation is to assess the effect of various additives on coalescence of nickel, copper and cobalt from slags generated during nickel extraction. The analyzed fluxes were silica and lime while examined reductants were pig iron, ferrosilicon and copper-silicon compound. Slag was settled at the different holding temperatures for various times in conditions that simulated the industrial environment. The newly formed matte and slag were characterized by their chemical composition and morphology. Silica flux generated higher partition coefficients for nickel and copper than the addition of lime. Additives used as reducing agents had higher valuable metal recovery rates and corresponding partition coefficients than fluxes. Microstructural studies showed that slag formed after adding reductants consisted of primarily fayalite, with some minute traces of magnetite as the secondary phase. Addition of 5 wt% of pig iron, ferrosilicon and copper-silicon alloys favored the formation of a metallized matte which increased Cu, Ni and Co recoveries. Addition of copper-silicon alloys with low silicon content was efficient in copper recovery but coalescence of the other metals was low. Slag treated with the ferrosilicon facilitated the highest cobalt recovery while copper-silicon alloys with silicon content above 10 wt% resulted in high coalescence of nickel and copper, 87 % and 72 % respectively.

Study of the role of the interface between niobium films and copper RF resonators

CERN Document Server

Benvenuti, Cristoforo; Campisi, I E; Darriulat, Pierre; Peck, M A; Russo, R

1997-01-01

Niobium-coated copper resonators are usually produced with an oxide interface between the film and the substrate. This oxide has two sources: the passivation layer inevitably formed on the surface of the cavity after chemical preparation before coating, and the niobium oxide which builds up on the surface of the cathode when it is exposed to air, and is transferred to the cavity surface during coa ting. The oxide layer may influence both the purity and the structural properties of the film, and in turn its RF behaviour. To study its effect, some cavities have been coated with a special two-cath ode sputtering system, allowing for a complete removal of both oxide layers by sputter-etching. For comparison, a few cavities have also been produced with the same coating system without sputter-etch ing, or with a controlled oxidation of the copper surface of the cavity after sputter-etching. Two cavities have also been produced without oxide interface using Kr and Ne as sputter gas instead of Ar .

The impact of porosity on the formation of manganese based copper diffusion barrier layers on low-κ dielectric materials

International Nuclear Information System (INIS)

McCoy, A P; Bogan, J; Walsh, L; Byrne, C; O’Connor, R; Hughes, G; Woicik, J C

2015-01-01

This work investigates the impact of porosity in low-κ dielectric materials on the chemical and structural properties of deposited Mn thin films for copper diffusion barrier layer applications. X-ray photoelectron spectrscopy (XPS) results highlight the difficulty in distinguishing between the various Mn oxidation states which form at the interlayer dielectric (ILD)/Mn interface. The presence of MnSiO 3 and MnO were identified using x-ray absorption spectroscopy (XAS) measurements on both porous and non-porous dielectric materials with evidence of Mn 2 O 3 and Mn 3 O 4 in the deposited film on the latter surface. It is shown that a higher proportion of deposited Mn converts to Mn silicate on an ILD film which has 50% porosity compared with the same dielectric material with no porosity, which is attributed to an enhanced chemical interaction with the effective larger surface area of porous dielectric materials. Transmission electron microscopy (TEM) and energy-dispersive x-ray spectroscopy (EDX) data shows that the Mn overlayer remains predominately surface localised on both porous and non-porous materials. (paper)

Antwerp Copper Plates

DEFF Research Database (Denmark)

Wadum, Jørgen

1999-01-01

In addition to presenting a short history of copper paintings, topics detail artists’ materials and techniques, as well as aspects of the copper industry, including mining, preparation and trade routes.......In addition to presenting a short history of copper paintings, topics detail artists’ materials and techniques, as well as aspects of the copper industry, including mining, preparation and trade routes....

Cathodic reduction of the duplex oxide films formed on copper in air with high relative humidity at 60 deg C

International Nuclear Information System (INIS)

Seo, M.; Ishikawa, Y.; Kodaira, M.; Sugimoto, A.; Nakayama, S.; Watanabe, M.; Furuya, S.; Minamitani, R.; Miyata, Y.; Nishikata, A.; Notoya, T.

2005-01-01

The cathodic reduction of duplex air-formed oxide film on copper was performed at a constant current density of i c = -50 μA cm -2 in deaerated 0.1 M KCl solution to investigate the sequence of cathodic reduction of each oxide layer and its mechanism. The single-phase thick CuO film on copper was also cathodically reduced at i c = -50 μA cm -2 or -2.5 mA cm -2 . The surface characterizations of the air-formed oxide film and single-phase CuO film before cathodic reduction and after partial or complete cathodic reduction were performed by XPS and X-ray diffraction, respectively. The two plateau regions appeared in the potential vs. time curve during cathodic reduction of the duplex air-formed oxide film on copper, while one plateau region was observed in the potential-time curve during cathodic reduction of the single-phase CuO film on copper. The potential in the first plateau region for the air-formed film coincided with that in the plateau region for the CuO film. The results of XPS and X-ray diffraction suggested that in the first plateau region, the outer CuO layer is directly reduced to metallic Cu, while in the second plateau region, the inner Cu 2 O layer is reduced to metallic Cu

Preparation of CuGaSe2 absorber layers for thin film solar cells by annealing of efficiently electrodeposited Cu-Ga precursor layers from ionic liquids

International Nuclear Information System (INIS)

Steichen, M.; Larsen, J.; Guetay, L.; Siebentritt, S.; Dale, P.J.

2011-01-01

CuGaSe 2 absorber layers were prepared on molybdenum substrates by electrochemical codeposition of copper and gallium and subsequential annealing in selenium vapour. The electrodeposition was made from a deep eutectic based ionic liquid consisting of choline chloride/urea (Reline) with a plating efficiency of over 85%. The precursor film composition is controlled by the ratio of the copper to gallium fluxes under hydrodynamic conditions and by the applied deposition potential. X-ray diffraction reveals CuGa 2 alloying during the electrodeposition and CuGaSe 2 formation after annealing. Photoluminescence (PL) and photocurrent spectroscopy revealed the good opto-electronic properties of the CuGaSe 2 absorber films. The absorber layers have been converted to full devices with the best device achieving 4.0 % solar conversion efficiency.

Speciation and leachability of copper in mine tailings from porphyry copper mining

DEFF Research Database (Denmark)

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

2005-01-01

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 1150mgkg^-^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@mm, 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...

Superconducting materials arrangement and realization process

International Nuclear Information System (INIS)

Pribat, D.; Dieumegard, D.; Garry, G.; Mercandalli, L.

1989-01-01

Thin and stable layers of the superconducting oxychloride YBa Cu OF with an accurate content of oxygen and fluorine can be obtained by the invention. The superconducting material is deposited on a substrate and encapsulated in an ionic conductor for adjustment of stoichiometry. Composition of the superconductor can be adjusted by electrolysis [fr

Copper and Anesthesia: Clinical Relevance and Management of Copper Related Disorders

OpenAIRE

Langley, Adrian; Dameron, Charles T.

2013-01-01

Recent research has implicated abnormal copper homeostasis in the underlying pathophysiology of several clinically important disorders, some of which may be encountered by the anesthetist in daily clinical practice. The purpose of this narrative review is to summarize the physiology and pharmacology of copper, the clinical implications of abnormal copper metabolism, and the subsequent influence of altered copper homeostasis on anesthetic management.

Fabrication of copper-based anodes via atmosphoric plasma spraying techniques

Science.gov (United States)

Lu, Chun [Monroeville, PA

2012-04-24

A fuel electrode anode (18) for a solid oxide fuel cell is made by presenting a solid oxide fuel cell having an electrolyte surface (15), mixing copper powder with solid oxide electrolyte in a mixing step (24, 44) to provide a spray feedstock (30,50) which is fed into a plasma jet (32, 52) of a plasma torch to melt the spray feed stock and propel it onto an electrolyte surface (34, 54) where the spray feed stock flattens into lamellae layer upon solidification, where the layer (38, 59) is an anode coating with greater than 35 vol. % based on solids volume.

Influence of electric current intensity on the performance of electroformed copper liner for shaped charge application

Directory of Open Access Journals (Sweden)

Tamer Elshenawy

2017-12-01

Full Text Available Electrolytic Copper used in the shaped charge liner manufacturing can be produced from acid solution using electro-deposition technique. The intensity of the applied electric current controls the quality of the produced copper grade. The electric current intensity within the electrolytic acidic solution cell with the minimum oxygen and sulfur elements in the produced copper was optimized and found to be 30–40 A/Ft2. The elemental composition of the obtained electrolytic copper was determined using high-end stationary vacuum spectrometer, while the oxygen was determined precisely using ELTRA ONH-2000 apparatus. Besides, SEM was used to investigate the shape of the copper texture inside the deposited layers and to determine the average grain size. New relations have been obtained between the applied current intensity and both the oxygen and sulfur contents and the average grain size of the produced copper. Experimental result showed that when the applied current density increases to a certain limit, the oxygen and sulfur content in the electrolytic copper decreases. Performance of the produced copper liner was investigated by the static firing of a small caliber shaped charge containing an electro-formed copper liners, where the penetration depth of the optimized electrolytic liner was enhanced by 22.7% compared to that of baseline non-optimized liner.

Industrial Tests to Modify Molten Copper Slag for Improvement of Copper Recovery

Science.gov (United States)

Guo, Zhengqi; Zhu, Deqing; Pan, Jian; Zhang, Feng; Yang, Congcong

2018-04-01

In this article, to improve the recovery of copper from copper slag by flotation process, industrial tests of the modification process involving addition of a composite additive into molten copper slag were conducted, and the modified slag was subjected to the flotation process to confirm the modification effect. The phase evolution of the slag in the modification process was revealed by thermodynamic calculations, x-ray diffraction, optical microscopy and scanning electron microscopy. The results show that more copper was transformed and enriched in copper sulfide phases. The magnetite content in the modified slag decreased, and that of "FeO" increased correspondingly, leading to a better fluidity of the molten slag, which improved the aggregation and growth of fine particles of the copper sulfide minerals. Closed-circuit flotation tests of the original and modified slags were conducted, and the results show that the copper recovery increased obviously from 69.15% to 73.38%, and the copper grade of concentrates was elevated slightly from 20.24% to 21.69%, further confirming that the industrial tests of the modification process were successful. Hence, the modification process has a bright future in industrial applications for enhancing the recovery of copper from the copper slag.

Study of fine films nature on the surface of copper band by photoelectron spectroscopy method

International Nuclear Information System (INIS)

Reznichenko, K.N.; Fedorov, V.N.; Shevakin, Yu.F.

1983-01-01

The composition of surface films formed on the copper band of industrial production under atmospheric conditions, its changes in thickness and determination of chemical state of the above films are studied. It has been found by the methods of X-ray photoelectronic and Auger-spectroscopy that defect formations on the surface of the copper band of industrial production represent copper oxides in the form of fine films, their change in colour from blue to dark blue probably is determined by different thickness of these defects. The said films on copper have practically identical chemical composition characterized by the presence of unequally valent copper, oxygen in various states (adsorbed and in the form of oxides), carbon and iron. By means of chemical shifts of the line Cu 2psub(3/2) and Ol s the presence in the external part of the film of CuO copper oxide is established and nearer to the interface surface film-metal-of Cu 2 O cuprous oxide which indicates a two-layer surface film structure. The presence of adsorbed carbon and iron in the film composition is a result of surface contamination

High-Density Chemical Intercalation of Zero-Valent Copper into Bi 2 Se 3 Nanoribbons

KAUST Repository

Koski, Kristie J.; Cha, Judy J.; Reed, Bryan W.; Wessells, Colin D.; Kong, Desheng; Cui, Yi

2012-01-01

A major goal of intercalation chemistry is to intercalate high densities of guest species without disrupting the host lattice. Many intercalant concentrations, however, are limited by the charge of the guest species. Here we have developed a general solution-based chemical method for intercalating extraordinarily high densities of zero-valent copper metal into layered Bi 2Se 3 nanoribbons. Up to 60 atom % copper (Cu 7.5Bi 2Se 3) can be intercalated with no disruption to the host lattice using a solution disproportionation redox reaction. © 2012 American Chemical Society.

High-Density Chemical Intercalation of Zero-Valent Copper into Bi 2 Se 3 Nanoribbons

KAUST Repository

Koski, Kristie J.

2012-05-09

A major goal of intercalation chemistry is to intercalate high densities of guest species without disrupting the host lattice. Many intercalant concentrations, however, are limited by the charge of the guest species. Here we have developed a general solution-based chemical method for intercalating extraordinarily high densities of zero-valent copper metal into layered Bi 2Se 3 nanoribbons. Up to 60 atom % copper (Cu 7.5Bi 2Se 3) can be intercalated with no disruption to the host lattice using a solution disproportionation redox reaction. © 2012 American Chemical Society.

Monitoring the layer-by-layer self-assembly of graphene and graphene oxide by spectroscopic ellipsometry.

Science.gov (United States)

Zhou, Kai-Ge; Chang, Meng-Jie; Wang, Hang-Xing; Xie, Yu-Long; Zhang, Hao-Li

2012-01-01

Thin films of graphene oxide, graphene and copper (II) phthalocyanine dye have been successfully fabricated by electrostatic layer-by-layer (LbL) assembly approach. We present the first variable angle spectroscopic ellipsometry (VASE) investigation on these graphene-dye hybrid thin films. The thickness evaluation suggested that our LbL assembly process produces highly uniform and reproducible thin films. We demonstrate that the refractive indices of the graphene-dye thin films undergo dramatic variation in the range close to the absorption of the dyes. This investigation provides new insight to the optical properties of graphene containing thin films and shall help to establish an appropriate optical model for graphene-based hybrid materials.

Adsorption studies of water on copper, nickel, and iron: assessment of the polarization model

International Nuclear Information System (INIS)

Lee, S.; Staehle, R.W.

1997-01-01

In the atmospheric corrosion of copper, nickel, and iron, the adsorption of water affects the corrosion rates. Knowledge of water adsorption and metal oxyhydroxide formation is important in understanding the atmospheric corrosion process. The purposes of the present research were (i) to measure the adsorption of water on metal surfaces as a function of temperature and relative humidity (RH) and (ii) to assess Bradley's polarization model of adsorption. In the present research, the quartz-crystal microbalance (QCM) technique was used to measure the mass changes of copper, nickel, and iron at 0 to 100% relative humidity and 7 to 90 C under nitrogen and air environments. Less water was adsorbed on copper, nickel, and iron which form oxides than on gold. The amount of water adsorption was similar on copper, nickel, and iron under N 2 and air carrier gases. Functional relationship was first proposed as a way to include dipole/induced dipole interactions between the adsorbents and water layers. (orig.)

Simulation of Natural Convection in the Oxide Layer of Three-Layer Corium Pool in an IVR

Energy Technology Data Exchange (ETDEWEB)

Kim, Su-Hyeon; Park, Hae-Kyun; Chung, Bum-Jin [Kyung Hee University, Yongin (Korea, Republic of)

2016-10-15

This paper describes the three-layer phenomena and preliminary plan to simulate the oxide layer experimentally. We will perform the mass transfer experiments using a copper sulfate-sulfuric acid (CuSO{sub 4}-H{sub 2}SO{sub 4}) electroplating system based on the heat and mass transfer analogy concept. By performing the mass transfer experiments, we can achieve the high buoyancy condition with small facilities. The test facility is semicircular whose bottom is chopped, simulating the oxide pool above the heavy metal layer in a three-layer configuration. We will measure the heat flux at the top plate, side wall and bottom plate, and compare these results with those for a two-layer pool. In a three-layer configuration, the upper light metal layer becomes thinner, increasing the focusing effect. Thus, it is important to evaluate the heat flux from the oxide pool to the upper metallic layer. However, there is few heat transfer studies for a three-layer configuration. This paper is to discuss and to make a plan for the heat transfer experiments of oxide pool in a three- layer system. We will perform the mass transfer experiments based on the heat and mass transfer analogy concept. The test results will be analyzed phenomenologically and compared with two-layer results.

Intrinsically water-repellent copper oxide surfaces; An electro-crystallization approach

Science.gov (United States)

Akbari, Raziyeh; Ramos Chagas, Gabriela; Godeau, Guilhem; Mohammadizadeh, Mohammadreza; Guittard, Frédéric; Darmanin, Thierry

2018-06-01

Use of metal oxide thin layers is increased due to their good durability under environmental conditions. In this work, the repeatable nanostructured crystalite Cu2O thin films, developed by electrodeposition method without any physical and chemical modifications, demonstrate good hydrophobicity. Copper (I) oxide (Cu2O) layers were fabricated on gold/Si(1 0 0) substrates by different electrodeposition methods i.e. galvanostatic deposition, cyclic voltammetry, and pulse potentiostatic deposition and using copper sulfate (in various concentrations) as a precursor. The greatest crystalline face on prepared Cu2O samples is (1 1 1) which is the most hydrophobic facet of Cu2O cubic structure. Indeed, different crystallite structures such as nanotriangles and truncated octahedrons were formed on the surface for various electrodeposition methods. The increase of the contact angle (θw) measured by the rest time, reaching to about 135°, was seen at different rates and electrodeposition methods. In addition, two-step deposition surfaces were also prepared by applying two of the mentioned methods, alternatively. In general, the morphology of the two-step deposition surfaces showed some changes compared to that of one-step samples, allowing the formation of different crystallite shapes. Moreover, the wettability behavior showd the larger θw of the two-step deposition layers compared to the related one-step deposition layers. Therefore, the highest observed θw was related to the one of two-step deposition layers due to the creation of small octahedral structures on the surface, having narrow and deep valleys. However, there was an exception which was due to the resulted big structures and broad valleys on the surface. So, it is possible to engineer different crystallites shapes using the proposed two-step deposition method. It is expected that hydrophobic crystallite thin films can be used in environmental and electronic applications to save energy and materials properties.

Electric and electrochemical properties of surface films formed on copper in the presence of bicarbonate anions

International Nuclear Information System (INIS)

Sirkiae, P.; Saario, T.; Maekelae, K.; Laitinen, T.; Bojinov, M.

1999-01-01

Copper is used as an outer shield of cast iron canisters planned for storage of spent nuclear fuel. The copper shield is responsible for the corrosion protection of the canister. The aim of the present work was to study the influence of bicarbonate (HCO 3 - ) anions on the stability of the copper oxide film. The work consists of a brief literature survey and an experimental part, in which voltammetry, electrochemical impedance spectroscopy and dc resistance measurements via the Contact Electric Resistance (CER) technique were used. The studies reported in the literature indicated that HCO 3 - ions increase the solubility of copper in the stability region of Cu(II). Thus they render the oxide film formed on copper susceptible to local damage and to localised corrosion at high potentials. Unfortunately, despite the great importance of bicarbonates in copper corrosion, most of the environments used in the electrochemical and corrosion studies are not comparable with repository conditions. In the existing studies either the bicarbonate concentrations or pH of the solutions were too high. In addition, no such studies were available, in which not only the effect of carbonate ions, but also possible synergetic effects of them with other aggressive ions would have been clarified. The voltammetric results of the experimental part of this work point to a bilayer structure of the anodic film on copper in neutral solutions containing HCO 3 - ions. The transport of ionic defects through a thin continuous p-type semiconductor layer was concluded to be the rate limiting step of the anodic oxidation of copper in the stability region of monovalent copper and in the mixed oxide (Cu(I)/Cu(II) oxide) region. Films formed in the divalent copper region did not show well-pronounced semiconductor behaviour. Substantial evidence was found in the voltammetric, CER and impedance results for the increased defectiveness of the anodic film in the Cu(II) region. The oxidation rate of copper in

Electric and electrochemical properties of surface films formed on copper in the presence of bicarbonate anions

Energy Technology Data Exchange (ETDEWEB)

Sirkiae, P.; Saario, T.; Maekelae, K.; Laitinen, T.; Bojinov, M. [VTT Manufacturing Technology, Espoo (Finland)

1999-11-01

Copper is used as an outer shield of cast iron canisters planned for storage of spent nuclear fuel. The copper shield is responsible for the corrosion protection of the canister. The aim of the present work was to study the influence of bicarbonate (HCO{sub 3}{sup -}) anions on the stability of the copper oxide film. The work consists of a brief literature survey and an experimental part, in which voltammetry, electrochemical impedance spectroscopy and dc resistance measurements via the Contact Electric Resistance (CER) technique were used. The studies reported in the literature indicated that HCO{sub 3}{sup -} ions increase the solubility of copper in the stability region of Cu(II). Thus they render the oxide film formed on copper susceptible to local damage and to localised corrosion at high potentials. Unfortunately, despite the great importance of bicarbonates in copper corrosion, most of the environments used in the electrochemical and corrosion studies are not comparable with repository conditions. In the existing studies either the bicarbonate concentrations or pH of the solutions were too high. In addition, no such studies were available, in which not only the effect of carbonate ions, but also possible synergetic effects of them with other aggressive ions would have been clarified. The voltammetric results of the experimental part of this work point to a bilayer structure of the anodic film on copper in neutral solutions containing HCO{sub 3}{sup -}ions. The transport of ionic defects through a thin continuous p-type semiconductor layer was concluded to be the rate limiting step of the anodic oxidation of copper in the stability region of monovalent copper and in the mixed oxide (Cu(I)/Cu(II) oxide) region. Films formed in the divalent copper region did not show well-pronounced semiconductor behaviour. Substantial evidence was found in the voltammetric, CER and impedance results for the increased defectiveness of the anodic film in the Cu(II) region. The

Current Status and Future Prospects of Copper Oxide Heterojunction Solar Cells

Directory of Open Access Journals (Sweden)

Terence K. S. Wong

2016-04-01

Full Text Available The current state of thin film heterojunction solar cells based on cuprous oxide (Cu2O, cupric oxide (CuO and copper (III oxide (Cu4O3 is reviewed. These p-type semiconducting oxides prepared by Cu oxidation, sputtering or electrochemical deposition are non-toxic, sustainable photovoltaic materials with application potential for solar electricity. However, defects at the copper oxide heterojunction and film quality are still major constraining factors for achieving high power conversion efficiency, η. Amongst the Cu2O heterojunction devices, a maximum η of 6.1% has been obtained by using pulsed laser deposition (PLD of AlxGa1−xO onto thermal Cu2O doped with Na. The performance of CuO/n-Si heterojunction solar cells formed by magnetron sputtering of CuO is presently limited by both native oxide and Cu rich copper oxide layers at the heterointerface. These interfacial layers can be reduced by using a two-step sputtering process. A high η of 2.88% for CuO heterojunction solar cells has been achieved by incorporation of mixed phase CuO/Cu2O nanopowder. CuO/Cu2O heterojunction solar cells fabricated by electrodeposition and electrochemical doping has a maximum efficiency of 0.64% after surface defect passivation and annealing. Finally, early stage study of Cu4O3/GaN deposited on sapphire substrate has shown a photovoltaic effect and an η of ~10−2%.

Current Status and Future Prospects of Copper Oxide Heterojunction Solar Cells

Science.gov (United States)

Wong, Terence K. S.; Zhuk, Siarhei; Masudy-Panah, Saeid; Dalapati, Goutam K.

2016-01-01

The current state of thin film heterojunction solar cells based on cuprous oxide (Cu2O), cupric oxide (CuO) and copper (III) oxide (Cu4O3) is reviewed. These p-type semiconducting oxides prepared by Cu oxidation, sputtering or electrochemical deposition are non-toxic, sustainable photovoltaic materials with application potential for solar electricity. However, defects at the copper oxide heterojunction and film quality are still major constraining factors for achieving high power conversion efficiency, η. Amongst the Cu2O heterojunction devices, a maximum η of 6.1% has been obtained by using pulsed laser deposition (PLD) of AlxGa1−xO onto thermal Cu2O doped with Na. The performance of CuO/n-Si heterojunction solar cells formed by magnetron sputtering of CuO is presently limited by both native oxide and Cu rich copper oxide layers at the heterointerface. These interfacial layers can be reduced by using a two-step sputtering process. A high η of 2.88% for CuO heterojunction solar cells has been achieved by incorporation of mixed phase CuO/Cu2O nanopowder. CuO/Cu2O heterojunction solar cells fabricated by electrodeposition and electrochemical doping has a maximum efficiency of 0.64% after surface defect passivation and annealing. Finally, early stage study of Cu4O3/GaN deposited on sapphire substrate has shown a photovoltaic effect and an η of ~10−2%. PMID:28773398

Copper nitrate redispersion to arrive at highly active silica-supported copper catalysts

NARCIS (Netherlands)

Munnik, P.|info:eu-repo/dai/nl/328228524; Wolters, M.|info:eu-repo/dai/nl/304829560; Gabrielsson, A.; Pollington, S.D.; Headdock, G.; Bitter, J.H.|info:eu-repo/dai/nl/160581435; de Jongh, P.E.|info:eu-repo/dai/nl/186125372; de Jong, K.P.|info:eu-repo/dai/nl/06885580X

2011-01-01

In order to obtain copper catalysts with high dispersions at high copper loadings, the gas flow rate and gas composition was varied during calcination of silica gel impregnated with copper nitrate to a loading of 18 wt % of copper. Analysis by X-ray diffraction (XRD), N2O chemisorption, and

Copper economy in Chlamydomonas: Prioritized allocation and reallocation of copper to respiration vs. photosynthesis

Science.gov (United States)

Kropat, Janette; Gallaher, Sean D.; Urzica, Eugen I.; Nakamoto, Stacie S.; Strenkert, Daniela; Tottey, Stephen; Mason, Andrew Z.; Merchant, Sabeeha S.

2015-01-01

Inorganic elements, although required only in trace amounts, permit life and primary productivity because of their functions in catalysis. Every organism has a minimal requirement of each metal based on the intracellular abundance of proteins that use inorganic cofactors, but elemental sparing mechanisms can reduce this quota. A well-studied copper-sparing mechanism that operates in microalgae faced with copper deficiency is the replacement of the abundant copper protein plastocyanin with a heme-containing substitute, cytochrome (Cyt) c6. This switch, which is dependent on a copper-sensing transcription factor, copper response regulator 1 (CRR1), dramatically reduces the copper quota. We show here that in a situation of marginal copper availability, copper is preferentially allocated from plastocyanin, whose function is dispensable, to other more critical copper-dependent enzymes like Cyt oxidase and a ferroxidase. In the absence of an extracellular source, copper allocation to Cyt oxidase includes CRR1-dependent proteolysis of plastocyanin and quantitative recycling of the copper cofactor from plastocyanin to Cyt oxidase. Transcriptome profiling identifies a gene encoding a Zn-metalloprotease, as a candidate effecting copper recycling. One reason for the retention of genes encoding both plastocyanin and Cyt c6 in algal and cyanobacterial genomes might be because plastocyanin provides a competitive advantage in copper-depleted environments as a ready source of copper. PMID:25646490

Evolution of the microstructure in nanocrystalline copper electrodeposits during room temperature storage

DEFF Research Database (Denmark)

Pantleon, Karen; Somers, Marcel A. J.

2007-01-01

The microstructure evolution in copper electrodeposits at room temperature (self-annealing) was investigated by means of X-ray diffraction analysis and simultaneous measurement of the electrical resistivity as a function of time. In-situ studies were started immediately after electrodeposition......, crystallographic texture changes by multiple twinning and a decrease of the electrical resistivity occurred as a function of time at room temperature. The kinetics of self-annealing is strongly affected by the layer thickness: the thinner the layer the slower is the microstructure evolution and self-annealing...

Canine Copper-Associated Hepatitis

NARCIS (Netherlands)

Dirksen, Karen; Fieten, Hille

2017-01-01

Copper-associated hepatitis is recognized with increasing frequency in dogs. The disease is characterized by centrolobular hepatic copper accumulation, leading to hepatitis and eventually cirrhosis. The only way to establish the diagnosis is by histologic assessment of copper distribution and copper

Morphology of micro- and nanoparticles emitted by copper plants in Western Poland

International Nuclear Information System (INIS)

Konarski, P.; Cwil, M.; Iwanejko, I.; Mierzejewska, A.; Diduszko, R.

2004-01-01

Aerosol particles were collected in the vicinity of copper plants in Western Poland and analysed by mass spectrometry methods like secondary ion mass spectrometry (SIMS), spark source mass spectrometry (SSMS) and X-ray diffraction to characterise the possible dangers for the environment and health. The motivation of the work was to approach the toxicological mechanisms that are triggered when aerosol nanoparticles enter the human body. Different analytical techniques were used in order to compare bulk and surface properties of particles. The particle collection was performed with nine-stage cascade impactor with rotating plates and also with micro-fibre quartz filter collector. SSMS bulk analysis of copper plant emitted particles shows the presence of over 30 elements, the concentration in wt.% of Cu, Pb, Zn and Cl is 30, 5, 2 and 1, respectively. XRD analysis of these particles shows crystalline phases of quartz and probable phases containing copper CuS 2 , lead Pb 2 SiO 4 , PbO - massicot, Pb 5 [OH][PO 4 ] 3 , Pb 3 SiO 5 , iron and calcium Ca[Mg 0.67 Fe 0.33 ][CO 3 ] - dolomite, ferroan, Ca[FeMg][CO 3 ] 2 - ankerite, Ca[MgFe]Si 2 O 6 - augite. Surface sensitive SIMS depth profile analysis revealed the core-shell structure of copper plant emitted particles. The obtained structure of these particles shows that surfaces of the particles are enriched in elements like chlorine, fluorine, lead and chromium with respect to the core concentrations of these elements. The cores are composed mainly of copper, oxygen and carbon containing compounds. Lead concentration is nearly two times greater at the surface layers of particles than in the cores. SIMS analysis of urban aerosol particles collected in Legnica shows compositional dependence with size. Surface shell layer concentration of lead is three times greater for coarse 6-15 μm particles than for tiny 300 nm-1 μm particles. Such non-uniform particle morphology may enhance the toxic properties of particles suspended in

Earth's copper resources estimated from tectonic diffusion of porphyry copper deposits

Science.gov (United States)

Kesler, Stephen E.; Wilkinson, Bruce H.

2008-03-01

Improved estimates of global mineral endowments are relevantto issues ranging from strategic planning to global geochemicalcycling. We have used a time-space model for the tectonic migrationof porphyry copper deposits vertically through the crust tocalculate Earth's endowment of copper in mineral deposits. Themodel relies only on knowledge of numbers and ages of porphyrycopper deposits, Earth's most widespread and important sourceof copper, in order to estimate numbers of eroded and preserveddeposits in the crust. Model results indicate that 125,895 porphyrycopper deposits were formed during Phanerozoic time, that only47,789 of these remain at various crustal depths, and that thesecontain 1.7 x 1011 tonnes (t) of copper. Assuming that othertypes of copper deposits behave similarly in the crust and haveabundances proportional to their current global production yieldsan estimate of 3 x 1011 t for total global copper resourcesat all levels in Earth's crust. Thus, 0.25% of the copper inthe crust has been concentrated into deposits through Phanerozoictime, and about two-thirds of this has been recycled by upliftand erosion. The amount of copper in deposits above 3.3 km,a likely limit of future mining, could supply current worldmine production for 5500 yr, thus quantifying the highly unusualand nonrenewable nature of mineral deposits.

Metagenome-scale analysis yields insights into the structure and function of microbial communities in a copper bioleaching heap.

Science.gov (United States)

Zhang, Xian; Niu, Jiaojiao; Liang, Yili; Liu, Xueduan; Yin, Huaqun

2016-01-19

Metagenomics allows us to acquire the potential resources from both cultivatable and uncultivable microorganisms in the environment. Here, shotgun metagenome sequencing was used to investigate microbial communities from the surface layer of low grade copper tailings that were industrially bioleached at the Dexing Copper Mine, China. A bioinformatics analysis was further performed to elucidate structural and functional properties of the microbial communities in a copper bioleaching heap. Taxonomic analysis revealed unexpectedly high microbial biodiversity of this extremely acidic environment, as most sequences were phylogenetically assigned to Proteobacteria, while Euryarchaeota-related sequences occupied little proportion in this system, assuming that Archaea probably played little role in the bioleaching systems. At the genus level, the microbial community in mineral surface-layer was dominated by the sulfur- and iron-oxidizing acidophiles such as Acidithiobacillus-like populations, most of which were A. ferrivorans-like and A. ferrooxidans-like groups. In addition, Caudovirales were the dominant viral type observed in this extremely environment. Functional analysis illustrated that the principal participants related to the key metabolic pathways (carbon fixation, nitrogen metabolism, Fe(II) oxidation and sulfur metabolism) were mainly identified to be Acidithiobacillus-like, Thiobacillus-like and Leptospirillum-like microorganisms, indicating their vital roles. Also, microbial community harbored certain adaptive mechanisms (heavy metal resistance, low pH adaption, organic solvents tolerance and detoxification of hydroxyl radicals) as they performed their functions in the bioleaching system. Our study provides several valuable datasets for understanding the microbial community composition and function in the surface-layer of copper bioleaching heap.

Comparison of oxidation resistance of copper treated by beam-line ion implantation and plasma immersion ion implantation

International Nuclear Information System (INIS)

An Quanzhang; Li Liuhe; Hu Tao; Xin Yunchang; Fu, Ricky K.Y.; Kwok, D.T.K.; Cai Xun; Chu, Paul K.

2009-01-01

Copper which has many favorable properties such as low cost, high thermal and electrical conductivity, as well as easy fabrication and joining is one of the main materials in lead frames, interconnects, and foils in flexible circuits. Furthermore, copper is one of the best antibacterial materials. However, unlike aluminum oxide or chromium oxide, the surface copper oxide layer does not render sufficient protection against oxidation. In this work, in order to improve the surface oxidation resistance of Cu, Al and N were introduced into copper by plasma immersion ion implantation (PIII) and beam-line ion implantation (BII). The implantation fluences of Al and N were 2 x 10 17 ions cm -2 and 5 x 10 16 ions cm -2 , respectively. The implanted and untreated copper samples were oxidized in air at 260 deg. C for 1 h. The X-ray diffraction (XRD), scanning electron microscopy (SEM), as well as X-ray photoelectron spectroscopy (XPS) results indicate that both implantation methods can enhance the oxidation resistance of copper but to different extent. PIII is superior to BII in enhancing the oxidation resistance of copper. The effects and possible mechanisms are discussed.

Growth graphene on silver-copper nanoparticles by chemical vapor deposition for high-performance surface-enhanced Raman scattering

Science.gov (United States)

Zhang, Xiumei; Xu, Shicai; Jiang, Shouzhen; Wang, Jihua; Wei, Jie; Xu, Shida; Gao, Shoubao; Liu, Hanping; Qiu, Hengwei; Li, Zhen; Liu, Huilan; Li, Zhenhua; Li, Hongsheng

2015-10-01

We present a graphene/silver-copper nanoparticle hybrid system (G/SCNPs) to be used as a high-performance surface-enhanced Raman scattering (SERS) substrate. The silver-copper nanoparticles wrapped by a monolayer graphene layer are directly synthesized on SiO2/Si substrate by chemical vapor deposition in a mixture of methane and hydrogen. The G/SCNPs shows excellent SERS enhancement activity and high reproducibility. The minimum detected concentration of R6G is as low as 10-10 M and the calibration curve shows a good linear response from 10-6 to 10-10 M. The date fluctuations from 20 positions of one SERS substrate are less than 8% and from 20 different substrates are less than 10%. The high reproducibility of the enhanced Raman signals could be due to the presence of an ultrathin graphene layer and uniform morphology of silver-copper nanoparticles. The use of G/SCNPs for detection of nucleosides extracted from human urine demonstrates great potential for the practical applications on a variety of detection in medicine and biotechnology field.

Determination of copper, iron and zinc in spirituous beverages by total reflection X-ray fluorescence spectrometry

Science.gov (United States)

Capote, T.; Marcó, L. M.; Alvarado, J.; Greaves, E. D.

1999-10-01

The concentration of copper in traditional homemade alcoholic distillates produced in Venezuela (Cocuy de Penca) were determined by total reflection X-ray fluorescence (TXRF) using vanadium as internal standard. The results were compared to those obtained by flame atomic absorption spectrometry (FAAS). Three preparative methods of addition of vanadium were compared: classical internal standard addition, 'layer on layer' internal standard addition and in situ addition of internal standard. The TXRF procedures were accurate and the precision was comparable to that obtained by the FAAS technique. Copper levels were above the maximum allowed limits for similar beverages. Zinc and iron in commercial and homemade distilled beverages were also analyzed by TXRF with in situ addition of internal standard demonstrating the usefulness of this technique for trace metal determination in distillates.

HEAVY METALS ABUNDANCE IN THE SOILS OF THE PANTELIMON – BRĂNEŞTI AREA, ILFOV COUNTY a CADMIUM, COBALT, CHROMIUM, COPPER

Directory of Open Access Journals (Sweden)

Radu Lacatusu

2011-12-01

Full Text Available More than 20 years later, a new research on heavy metals (cadmium, cobalt, chromium, copper contents in the soil cover of the Pantelimon – Brăneşti area located East of the Bucharest Municipality and exposed for several decades to the influence of industrial emissions from two non-ferrous metallurgy plants is presented. A 5,912.72 ha area was investigated, 544 samples taken by geometric horizons (0-20; 20-40; 40-60 cm from 215 points have been analyzed.The dominant soils are: Preluvosols, Chernozems, Phaeozems. The analytical data showed that all the heavy metals contents are below the maximum allowable limits and of the alarm thresholds. Higher cadmium and copper concentrations have been registered in the 40-60 cm layer and higher chromium and copper concentrations in the 0-20 cm layer. Cadmium and cobalt distributions are non-central, with a right asymmetry, and the chromium and copper ones are slightly symmetric. The surface distribution of the heavy metals shows the presence of some high contents areas distributed insularly, with a higher frequency around the industrial units. The geochemical abundance indexes are higher than 1 for cadmium and lower for cobalt, chromium, and copper, and the pedo-geochemical abundance indexes are lower than 1 only for chromium.

Self-healing coatings based on halloysite clay polymer composites for protection of copper alloys.

Science.gov (United States)

Abdullayev, Elshad; Abbasov, Vagif; Tursunbayeva, Asel; Portnov, Vasiliy; Ibrahimov, Hikmat; Mukhtarova, Gulbaniz; Lvov, Yuri

2013-05-22

Halloysite clay nanotubes loaded with corrosion inhibitors benzotriazole (BTA), 2-mercaptobenzimidazole (MBI), and 2-mercaptobenzothiazole (MBT) were used as additives in self-healing composite paint coating of copper. These inhibitors form protective films on the metal surface and mitigate corrosion. Mechanisms involved in the film formation have been studied with optical and electron microscopy, UV-vis spectrometry, and adhesivity tests. Efficiency of the halloysite lumen loading ascended in the order of BTA halloysite formulations have shown the best protection. Inhibitors were kept in the tubes buried in polymeric paint layer for a long time and release was enhanced in the coating defects exposed to humid media with 20-50 h, sufficient for formation of protective layer. Anticorrosive performance of the halloysite-based composite acrylic and polyurethane coatings have been demonstrated for 110-copper alloy strips exposed to 0.5 M aqueous NaCl for 6 months.

Electropolymerization of poly (aniline-co-o-anisidine) on copper and its anticorrosion properties

International Nuclear Information System (INIS)

Ozyilmaz, A T

2008-01-01

Poly(aniline-co-o-anisidine) of copolymer coatings was synthesized on the copper surface (Cu) with two different amounts of p-toluenesulfonic acid (p-TSA) added to the aqueous sodium oxalate (NaOX) solution. The copper substrates in NaOX solutions containing p-TSA acid had a fairly reliable passive surface mainly due to the formation of copper (II) oxalate layer. The addition of p-TSA acid to the working electrolyte contributed to both the amount of copolymer deposition (growth) and that of copolymer coated per unit time of electropolymerization (growth rate). The growth of copolymer coating on Cu electrode was characterized by scanning electron microscopy. The corrosion performances of copolymer coatings were investigated in 3.5% NaCl solution with anodic polarization curves and electrochemical impedance spectroscopy. The results showed that p-TSA acid led to the diminishing of the permeability of the copolymer films. The copolymer coatings exhibited an effective barrier property on copper electrode and a remarkable anodic protection to substrate for longer exposure time

Stage specific effects of soluble copper and copper oxide nanoparticles during sea urchin embryo development and their relation to intracellular copper uptake.

Science.gov (United States)

Torres-Duarte, Cristina; Ramos-Torres, Karla M; Rahimoff, René; Cherr, Gary N

2017-08-01

The effects of exposure to either soluble copper (copper sulfate) or copper oxide nanoparticles (nano-CuO) during specific early developmental stages of sea urchin embryos were analyzed. Soluble copper caused significant malformations in embryos (skeletal malformations, delayed development or gut malformations) when present at any given stage, while cleavage stage was the most sensitive to nano-CuO exposure causing skeletal malformations and decreased total antioxidant capacity. The stage specificity was linked to higher endocytic activity during the first hours of development that leads to higher accumulation of copper in specific cells critical for development. Results indicate that nano-CuO results in higher accumulation of copper inside of embryos and this intracellular copper is more persistent as compared to soluble copper. The possible implications later in development are discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

Surface investigation of naturally corroded gilded copper-based objects

Energy Technology Data Exchange (ETDEWEB)

Ingo, G.M., E-mail: gabriel.ingo@ismn.cnr.it [Istituto per lo Studio dei Materiali Nanostrutturati—Consiglio Nazionale delle Ricerche (ISMN—CNR), Area della Ricerca del CNR Roma1-Montelibretti, via Salaria Km 29.3, 00016 Monterotondo Scalo, Rome (Italy); Riccucci, C. [Istituto per lo Studio dei Materiali Nanostrutturati—Consiglio Nazionale delle Ricerche (ISMN—CNR), Area della Ricerca del CNR Roma1-Montelibretti, via Salaria Km 29.3, 00016 Monterotondo Scalo, Rome (Italy); Lavorgna, M.; Salzano de Luna, M. [Istituto per i Polimeri, Compositi e Biomateriali—Consiglio Nazionale delle Ricerche (IPCB—CNR), P.le E. Fermi 1, 80050 Portici, Napoli (Italy); Pascucci, M. [Istituto per lo Studio dei Materiali Nanostrutturati—Consiglio Nazionale delle Ricerche (ISMN—CNR), Area della Ricerca del CNR Roma1-Montelibretti, via Salaria Km 29.3, 00016 Monterotondo Scalo, Rome (Italy); Di Carlo, G., E-mail: gabriella.dicarlo@ismn.cnr.it [Istituto per lo Studio dei Materiali Nanostrutturati—Consiglio Nazionale delle Ricerche (ISMN—CNR), Area della Ricerca del CNR Roma1-Montelibretti, via Salaria Km 29.3, 00016 Monterotondo Scalo, Rome (Italy)

2016-11-30

Highlights: • Naturally corroded Au and Ag coated Cu-based objects studied by XPS, SEM + EDS and OM. • The main degrading agents are Cl, S and P species from surrounding environment. • Metal galvanic coupling enhances corrosion phenomena. • Corrosion forms a layered patina of noble metal remains, soil components and Cu{sub 2}O. • Useful information to tailor safe cleaning and reliable conservation strategies. - Abstract: Gold and silver coated copper-based artefacts subjected to long-term natural corrosion phenomena were studied by means of the combined use of X-ray photoelectron spectroscopy (XPS), scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM + EDS), and optical microscopy (OM). The results allowed the identification of the chemistry and structure of the Au or Ag layers deposited by fire-gilding or mercury-silvering and the determination of the corrosion products formed due to interaction with the surrounding environment. Different degradation phenomena of the noble metal layer and copper substrate are induced by the presence of chlorine, sulphur and phosphorous and they are boosted by the metal galvanic coupling which makes gilded-metal art works unstable from a chemico-physical point of view. The SEM + EDS and OM results also suggest that particular care must be used during the removal of the encrustations and of the external corrosion products to avoid the loss of the remains of the noble layer often floating or embedded in the corrosion products. Furthermore, in order to avoid the reaction between nantokite (CuCl) and moisture the use no or low toxic inhibitors is suggested to avoid further severe degradation phenomena enhancing the long-lasting chemico-physical stability of these precious artefacts and giving them a greater chance of survival.

Genome Sequences of Two Copper-Resistant Escherichia coli Strains Isolated from Copper-Fed Pigs

DEFF Research Database (Denmark)

Lüthje, Freja L.; Hasman, Henrik; Aarestrup, Frank Møller

2014-01-01

The draft genome sequences of two copper-resistant Escherichia coli strains were determined. These had been isolated from copper-fed pigs and contained additional putative operons conferring copper and other metal and metalloid resistances.......The draft genome sequences of two copper-resistant Escherichia coli strains were determined. These had been isolated from copper-fed pigs and contained additional putative operons conferring copper and other metal and metalloid resistances....

Effect of Copper on the Carrier Lifetime in Black Silicon

DEFF Research Database (Denmark)

Porte, Henrik; Turchinovich, Dmitry; Persheyev, Saydulla

2011-01-01

Black silicon is produced by laser annealing of a-Si:H films. During annealing, silicon microstructures are formed on the surface. We use time-resolved terahertz spectroscopy to study the photoconductivity dynamics in black silicon. We find that when a copper film is deposited on top of the a......-Si:H layer prior to laser annealing, the carrier lifetime of black silicon is significantly reduced....

Copper and CuNi alloys substrates for HTS coated conductor applications protected from oxidation

Energy Technology Data Exchange (ETDEWEB)

Segarra, M; Diaz, J; Xuriguera, H; Chimenos, J M; Espiell, F [Dept. of Chemical Engineering and Metallurgy, Univ. of Barcelona, Barcelona (Spain); Miralles, L [Lab. d' Investigacio en Formacions Geologiques. Dept. of Petrology, Geochemistry and Geological Prospecting, Univ. of Barcelona, Barcelona (Spain); Pinol, S [Inst. de Ciencia de Materials de Barcelona, Bellaterra (Spain)

2003-07-01

Copper is an interesting substrate for HTS coated conductors for its low cost compared to other metallic substrates, and for its low resistivity. Nevertheless, mechanical properties and resistance to oxidation should be improved in order to use it as substrate for YBCO deposition by non-vacuum techniques. Therefore, different cube textured CuNi tapes were prepared by RABIT as possible substrates for deposition of high critical current density YBCO films. Under the optimised conditions of deformation and annealing, all the studied CuNi alloys (2%, 5%, and 10% Ni) presented (100) left angle 001 right angle cube texture which is compatible for YBCO deposition. Textured CuNi alloys present higher tensile strength than pure copper. Oxidation resistance of CuNi tapes under different oxygen atmospheres was also studied by thermogravimetric analysis and compared to pure copper tapes. Although the presence of nickel improves mechanical properties of annealed copper, it does not improve its oxidation resistance. However, when a chromium buffer layer is electrodeposited on the tape, oxygen diffusion is slowed down. Chromium is, therefore, useful for protecting copper and CuNi alloys from oxidation although its recrystallisation texture, (110), is not suitable for coated conductors. (orig.)

Sputtering induced surface composition changes in copper-palladium alloys

International Nuclear Information System (INIS)

Sundararaman, M.; Sharma, S.K.; Kumar, L.; Krishnan, R.

1981-01-01

It has been observed that, in general, surface composition is different from bulk composition in multicomponent materials as a result of ion beam sputtering. This compositional difference arises from factors like preferential sputtering, radiation induced concentration gradients and the knock-in effect. In the present work, changes in the surface composition of copper-palladium alloys, brought about by argon ion sputtering, have been studied using Auger electron spectroscopy. Argon ion energy has been varied from 500 eV to 5 keV. Enrichment of palladium has been observed in the sputter-altered layer. The palladium enrichment at the surface has been found to be higher for 500 eV argon ion sputtering compared with argon ion sputtering at higher energies. Above 500 eV, the surface composition has been observed to remain the same irrespective of the sputter ion energy for each alloy composition. The bulk composition ratio of palladium to copper has been found to be linearly related to the sputter altered surface composition ratio of palladium to copper. These results are discussed on the basis of recent theories of alloy sputtering. (orig.)

Irradiation effects in tungsten-copper laminate composite

Energy Technology Data Exchange (ETDEWEB)

Garrison, L.M., E-mail: garrisonlm@ornl.gov [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Katoh, Y. [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Snead, L.L. [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Byun, T.S. [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Reiser, J.; Rieth, M. [Karlsruhe Institute of Technology, Karlsruhe (Germany)

2016-12-01

Tungsten-copper laminate composite has shown promise as a structural plasma-facing component as compared to tungsten rod or plate. The present study evaluated the tungsten-copper composite after irradiation in the High Flux Isotope Reactor (HFIR) at temperatures of 410–780 °C and fast neutron fluences of 0.02–9.0 × 10{sup 25} n/m{sup 2}, E > 0.1 MeV, 0.0039–1.76 displacements per atom (dpa) in tungsten. Tensile tests were performed on the composites, and the fracture surfaces were analyzed with scanning electron microscopy. Before irradiation, the tungsten layers had brittle cleavage failure, but the overall composite had 15.5% elongation at 22 °C. After only 0.0039 dpa this was reduced to 7.7% elongation, and no ductility was observed after 0.2 dpa at all irradiation temperatures when tensile tested at 22 °C. For elevated temperature tensile tests after irradiation, the composite only had ductile failure at temperatures where the tungsten was delaminating or ductile. - Highlights: • Fusion reactors need a tough, ductile tungsten plasma-facing material. • The unirradiated tungsten-copper laminate is more ductile than tungsten alone. • After neutron irradiation, the composite has significantly less ductility. • The tungsten behavior appears to dominate the overall composite behavior.

Mode-locking of an InAs Quantum Dot Based Vertical External Cavity Surface Emitting Laser Using Atomic Layer Graphene

Science.gov (United States)

2015-07-16

catalyzed on either a copper foil or on nickel coated substrates. The graphene must be transferred off of these substrates and then on to the DBR/spacer to...properties of graphene in both the exfoliated single layer graphene (SLG) and few layer graphene (FLG) flakes . Sun et al. make use of bile salts to...semiconductors and dielectrics is the transfer of CVD graphene grown on copper foils. The graphene is grown on thin Cu-foils by CVD using methane and

Copper uptake and retention in liver parenchymal cells isolated from nutritionally copper-deficient rats

NARCIS (Netherlands)

Berg, van den G.J.; de Goeij, J.J.M.; Bock, I.; Gijbels, M.J.J.; Brouwer, A.; Lei, K.Y.; Hendriks, H.F.J.

1991-01-01

Copper uptake and retention were studied in primary cultures of liver parenchymal cells isolated from copper-deficient rats. Male Sprague-Dawley rats were fed a copper-deficient diet (<1 mg Cu/kg) for 10 wk. Copper-deficient rats were characterized by low copper concentrations in plasma and liver,

Copper uptake and retention in liver parenchymal cells isolated from nutritionally copper-deficient rats

NARCIS (Netherlands)

Berg, G.J. van den; Goeij, J.J.M. de; Bock, I.; Gijbels, M.J.J.; Brouwer, A.; Lei, K.Y.; Hendruiks, H.F.J.

1991-01-01

Copper uptake and retention were studied in primary cultures of liver parenchymal cells isolated from copper-deficient rats. Male Sprague-Dawley rats were fed a copper-deficient diet (< 1 mg Cu/kg) for 10 wk. Copper-deficient rats were characterized by low copper concentrations in plasma and liver,

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

International Nuclear Information System (INIS)

McCormick, Stephen F.

2016-01-01

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/

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

Energy Technology Data Exchange (ETDEWEB)

McCormick, Stephen F. [Front Range Scientific, Inc., Lake City, CO (United States)

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/.

Copper wire bonding

CERN Document Server

Chauhan, Preeti S; Zhong, ZhaoWei; Pecht, Michael G

2014-01-01

This critical volume provides an in-depth presentation of copper wire bonding technologies, processes and equipment, along with the economic benefits and risks.  Due to the increasing cost of materials used to make electronic components, the electronics industry has been rapidly moving from high cost gold to significantly lower cost copper as a wire bonding material.  However, copper wire bonding has several process and reliability concerns due to its material properties.  Copper Wire Bonding book lays out the challenges involved in replacing gold with copper as a wire bond material, and includes the bonding process changes—bond force, electric flame off, current and ultrasonic energy optimization, and bonding tools and equipment changes for first and second bond formation.  In addition, the bond–pad metallurgies and the use of bare and palladium-coated copper wires on aluminum are presented, and gold, nickel and palladium surface finishes are discussed.  The book also discusses best practices and re...

Nearly 60% Copper Rod & Wire Companies Neutral about Future Copper Price

Institute of Scientific and Technical Information of China (English)

2012-01-01

<正>How about the trend of copper price recently? According to the survey result of Shanghai Metals Market, amongst 21 domestic copper rod & wire companies, 57% of the companies are neutral about the future copper price, while 14% and 19% of the companies consider that

The effect of donor layer thickness on the power conversion efficiency of organic photovoltaic devices fabricated with a double small-molecular layer

International Nuclear Information System (INIS)

Lee, Su-Hwan; Kim, Dal-Ho; Shim, Tae-Hun; Park, Jea-Gun

2009-01-01

In organic photovoltaic (OPV) devices fabricated with a double small-molecular layer, the power conversion efficiency strongly depends on the thickness of the organic donor layer (here, copper phthalocyanine). In other words, the power conversion efficiency increases with the donor layer thickness up to a specific thickness (∼12.7 nm) and then decreases beyond that thickness. This trend is associated with the light absorption and carrier transport resistance of the small-molecular donor layer, both of which strongly depend on the layer thickness. Experimental and calculated results showed that the short-circuit current due to light absorption increased with the donor layer thickness, while that due to current through the donor layer decreased with 1/R. Since the total short-circuit current is the product of the light absorption current and current through the donor layer, there is a trade-off, and the maximum power conversion efficiency occurs at a specific organic donor layer thickness (e.g. ∼12.7 nm in this experiment).

Cephradine as corrosion inhibitor for copper in 0.9% NaCl solution

Science.gov (United States)

Tasić, Žaklina Z.; Petrović Mihajlović, Marija B.; Radovanović, Milan B.; Simonović, Ana T.; Antonijević, Milan M.

2018-05-01

The effect of (6R,7R)-7-[[(2R)-2-amino-2-cyclohexa-1,4-dien-1-ylacetyl]amino]-3-methyl-8-oxo-5-thia-1-azobicyclo[4.2.0]oct-2-ene-2-carboxylic acid (cephradine) on corrosion behavior of copper in 0.9% NaCl solution was investigated. The electrochemical methods including the open circuit potential measurements, potentiodynamic polarization and electrochemical impedance spectroscopy measurements, scanning electron microscopy with energy dispersive X-ray spectroscopy and quantum chemical calculations were used for this investigation. According to the results obtained by potentiodynamic polarization, cephradine acts as mixed type inhibitor. Also, the results obtained by electrochemical impedance spectroscopy indicate that cephradine provides good copper protection in 0.9% NaCl solution. The inhibition efficiency of cephradine increases with increasing its concentration. The scanning electron microscopy with energy dispersive X-ray spectroscopy confirms that a protective layer is formed on the copper surface due to the adsorption of cephradine on the active sites on the copper surface. Adsorption of cephradine in 0.9% NaCl solution follows the Langmuir adsorption isotherm. Quantum chemical calculations are in agreement with results obtained by electrochemical measurements.

First prototype Copper-Niobium RF Superconducting Cavity

CERN Multimedia

1983-01-01

This is the first RF superconducting cavity made of copper with a very thin layer of pure niobium deposited on the inner wall by sputtering. This new developpment lead to a considerable increase of performance and stability of superconducting cavities and to non-negligible economy. The work was carried out in the ISR workshop. This technique was adopted for the LEP II accelerating cavities. At the centre is Cristoforo Benvenuti, inventor of this important technology, with his assistants, Nadia Circelli and Max Hauer, carrying the sputtering electrode. See also 8209255, 8312339.

Influence of pulse ratio on codeposition of copper species with calcium phosphate coatings on titanium by means of electrochemically assisted deposition.

Science.gov (United States)

Wolf-Brandstetter, Cornelia; Oswald, Steffen; Bierbaum, Susanne; Wiesmann, Hans-Peter; Scharnweber, Dieter

2014-01-01

Aim of this study was to combine the well-known biocompatibility and ostoeconductivity of thin calcium phosphate coatings on titanium with proangiogenic signals from codeposited copper species. Copper species could be integrated in mineral layers based on hydroxyapatite by means of electrochemically assisted deposition from electrolytes containing calcium, phosphate, and copper ions. Different combinations of duration and intensity of galvanostatic pulses result in different amounts of deposited calcium phosphate and of copper species even for the same applied total charge. Absolute amounts of copper varied between 2.1 and 6.9 μg/cm², and the copper was distributed homogeneously as shown by EDX mapping. The presence of copper did not change the crystalline phase of deposited calcium phosphate (hydroxyapatite) but provoked a significant decrease in deposited amounts by factor 3 to 4. The copper was deposited mainly as Cu(I) species with a minor fraction of basic copper phosphates. Reduction of copper occurred not only at the surface of titanium but also within the hydroxyapatite coating due to the reaction with hydrogen produced by the electrolysis of water during the cathodic polarization of the substrate. Copyright © 2013 Wiley Periodicals, Inc.

Immunotoxicity of copper nanoparticle and copper sulfate in a common Indian earthworm.

Science.gov (United States)

Gautam, Arunodaya; Ray, Abhishek; Mukherjee, Soumalya; Das, Santanu; Pal, Kunal; Das, Subhadeep; Karmakar, Parimal; Ray, Mitali; Ray, Sajal

2018-02-01

Copper oxide nanoparticles and copper sulfate are established contaminants of water and soil. Metaphire posthuma is a common variety of earthworm distributed in moist soil of Indian subcontinent. Comparative toxicity of copper nanoparticles and copper sulfate were investigated with reference to selected immune associated parameters of earthworm. Total count, phagocytic response, generation of cytotoxic molecules (superoxide anion, nitric oxide), activities of enzymes like phenoloxidase, superoxide dismutase, catalase, acid phosphatase, alkaline phosphatase and total protein of coelomocytes were estimated under the exposures of 100, 500, 1000mg of copper oxide nanoparticles and copper sulfate per kg of soil for 7 and 14 d. A significant decrease in the total coelomocyte count were recorded with maximum depletion as 15.45 ± 2.2 and 12.5 ± 2 × 10 4 cells/ml under the treatment of 1000mg/kg of copper nanoparticles and copper sulfate for 14 d respectively. A significant decrease in generation of nitric oxide and activity of phenoloxidase were recorded upon exposure of both toxins for 7 and 14 d indicating possible decline in cytotoxic status of the organism. A maximum inhibition of superoxide dismutase activity was recorded as 0.083 ± 0.0039 and 0.055 ± 0.0057 unit/mg protein/minute against 1000mg/kg of copper nanoparticles and copper sulfate treatment for 14 d respectively. Activities of catalase and alkaline phosphatase were inhibited by all experimental concentrations of both toxins in the coelomocytes of earthworm. These toxins were recorded to be modifiers of the major immune associated parameters of M. posthuma. Unrestricted contamination of soil by sulfate and oxide nanoparticles of copper may lead to an undesirable shift in the innate immunological status of earthworm leading to a condition of immune compromisation and shrinkage in population density of this species in its natural habitat. This article is the first time report of immunological toxicity of

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

International Nuclear Information System (INIS)

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

Transfer-free batch fabrication of single layer graphene transistors.

Science.gov (United States)

Levendorf, Mark P; Ruiz-Vargas, Carlos S; Garg, Shivank; Park, Jiwoong

2009-12-01

Full integration of graphene into conventional device circuitry would require a reproducible large scale graphene synthesis that is compatible with conventional thin film technology. We report the synthesis of large scale single layer graphene directly onto an evaporated copper film. A novel fabrication method was used to directly pattern these graphene sheets into devices by simply removing the underlying copper film. Raman and conductance measurements show that the mechanical and electrical properties of our single layer graphene are uniform over a large area, ( Ferrari, A. C. et al. Phys. Rev. Lett. 2006, 97, 187401.) which leads to a high device yield and successful fabrication of ultra long (>0.5 mm) graphene channels. Our graphene based devices present excellent electrical properties including a promising carrier mobility of 700 cm(2)/V.s and current saturation characteristics similar to devices based on exfoliated graphene ( Meric, I.. et al. Nat Nanotechnol. 2008, 3, 654-659).

X-ray diffraction investigation of self-annealing in nanocrystalline copper electrodeposits

DEFF Research Database (Denmark)

Pantleon, Karen; Somers, Marcel A. J.

2006-01-01

X-ray diffraction analysis and electrical resistivity measurements were conducted simultaneously for in-situ examination of self-annealing in copper electrodeposits. Considerable growth of the as-deposited nano-sized crystallites occurs with time and the crystallographic texture changes by multip...... twinning during self-annealing. The kinetics of self-annealing depends on the layer thickness as well as on the orientation and/or the size of the as-deposited crystallites. (c) 2006 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.......X-ray diffraction analysis and electrical resistivity measurements were conducted simultaneously for in-situ examination of self-annealing in copper electrodeposits. Considerable growth of the as-deposited nano-sized crystallites occurs with time and the crystallographic texture changes by multiple...

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

Science.gov (United States)

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.

Graphite fiber/copper composites prepared by spontaneous infiltration

Science.gov (United States)

Wang, Hongbao; Tao, Zechao; Li, Xiangfen; Yan, Xi; Liu, Zhanjun; Guo, Quangui

2018-05-01

The major bottleneck in developing graphite fiber reinforced copper (GF/Cu) composites is the poor wettability of Cu/graphite system. Alloying element of chromium (Cr) is introduced to improve the wettability of liquid copper on graphite. Sessile drop method experiments illustrate that the contact angle of liquid Cu-Cr (1.0 wt.%) alloy on graphite substrate decreases to 43° at 1300 °C. The improvement of wettability is related to the formation of chromium carbide layer at interface zone. Based on the wetting experiment, a spontaneous infiltration method for preparing GF/Cu composites is proposed. Unidirectional GF preforms are infiltrated by Cu-Cr alloys without external pressure in a tubular furnace. Results reveal that the GF preform can be fully infiltrated by Cu-Cr alloy (8 wt.%) spontaneously when fiber volume fraction is 40%. The coefficient of thermal expansion (CTE) of GF/Cu-Cr (8.0 wt.%) composites is 4.68 × 10-6/K along the longitudinal direction.

Development and tests of molybdenum armored copper components for MITICA ion source

Science.gov (United States)

Pavei, Mauro; Böswirth, Bernd; Greuner, Henri; Marcuzzi, Diego; Rizzolo, Andrea; Valente, Matteo

2016-02-01

In order to prevent detrimental material erosion of components impinged by back-streaming positive D or H ions in the megavolt ITER injector and concept advancement beam source, a solution based on explosion bonding technique has been identified for producing a 1 mm thick molybdenum armour layer on copper substrate, compatible with ITER requirements. Prototypes have been recently manufactured and tested in the high heat flux test facility Garching Large Divertor Sample Test Facility (GLADIS) to check the capability of the molybdenum-copper interface to withstand several thermal shock cycles at high power density. This paper presents both the numerical fluid-dynamic analyses of the prototypes simulating the test conditions in GLADIS as well as the experimental results.

Development and tests of molybdenum armored copper components for MITICA ion source

International Nuclear Information System (INIS)

Pavei, Mauro; Marcuzzi, Diego; Rizzolo, Andrea; Valente, Matteo; Böswirth, Bernd; Greuner, Henri

2016-01-01

In order to prevent detrimental material erosion of components impinged by back-streaming positive D or H ions in the megavolt ITER injector and concept advancement beam source, a solution based on explosion bonding technique has been identified for producing a 1 mm thick molybdenum armour layer on copper substrate, compatible with ITER requirements. Prototypes have been recently manufactured and tested in the high heat flux test facility Garching Large Divertor Sample Test Facility (GLADIS) to check the capability of the molybdenum-copper interface to withstand several thermal shock cycles at high power density. This paper presents both the numerical fluid-dynamic analyses of the prototypes simulating the test conditions in GLADIS as well as the experimental results

Development and tests of molybdenum armored copper components for MITICA ion source

Energy Technology Data Exchange (ETDEWEB)

Pavei, Mauro, E-mail: mauro.pavei@igi.cnr.it; Marcuzzi, Diego; Rizzolo, Andrea; Valente, Matteo [Consorzio RFX, Corso Stati Uniti, 4, I-35127 Padova (Italy); Böswirth, Bernd; Greuner, Henri [Max-Planck-Institut für Plasmaphysik, Boltzmannstrasse 2, D-85748 Garching (Germany)

2016-02-15

In order to prevent detrimental material erosion of components impinged by back-streaming positive D or H ions in the megavolt ITER injector and concept advancement beam source, a solution based on explosion bonding technique has been identified for producing a 1 mm thick molybdenum armour layer on copper substrate, compatible with ITER requirements. Prototypes have been recently manufactured and tested in the high heat flux test facility Garching Large Divertor Sample Test Facility (GLADIS) to check the capability of the molybdenum-copper interface to withstand several thermal shock cycles at high power density. This paper presents both the numerical fluid-dynamic analyses of the prototypes simulating the test conditions in GLADIS as well as the experimental results.

Phase and structural transformations in annealed copper coatings in relation to oxide whisker growth

Energy Technology Data Exchange (ETDEWEB)

Dorogov, M.V.; Priezzheva, A.N. [Togliatti State University, Belorusskaya 14, 445667 Togliatti (Russian Federation); Vlassov, S., E-mail: vlassovs@ut.ee [Institute of Solid State Physics, University of Latvia, Kengaraga 8, LV-1063 Riga (Latvia); Kink, I.; Shulga, E. [Institute of Physics, University of Tartu, Ravila 14c, 50411 Tartu (Estonia); Dorogin, L.M. [Togliatti State University, Belorusskaya 14, 445667 Togliatti (Russian Federation); Institute of Physics, University of Tartu, Ravila 14c, 50411 Tartu (Estonia); ITMO University, Kronverkskiy 49, 197101 Saint Petersburg (Russian Federation); Lõhmus, R. [Institute of Physics, University of Tartu, Ravila 14c, 50411 Tartu (Estonia); Tyurkov, M.N.; Vikarchuk, A.A. [Togliatti State University, Belorusskaya 14, 445667 Togliatti (Russian Federation); Romanov, A.E. [Togliatti State University, Belorusskaya 14, 445667 Togliatti (Russian Federation); Institute of Physics, University of Tartu, Ravila 14c, 50411 Tartu (Estonia); ITMO University, Kronverkskiy 49, 197101 Saint Petersburg (Russian Federation); Ioffe Physical Technical Institute, RAS, Polytechnicheskaya 26, 194021 Saint Petersburg (Russian Federation)

2015-08-15

Highlights: • Coatings prepared by Cu microparticle electrodeposition. • Structural and phase transformation in Cu coatings annealed at 400 °C. • Annealing is accompanied by intensive growth of CuO whiskers. • Layered oxide phases (Cu{sub 2}O and CuO) in the coating are characterized. • Formation of volumetric defects in the coating is demonstrated. - Abstract: We describe structural and phase transformation in copper coatings made of microparticles during heating and annealing in air in the temperature range up to 400 °C. Such thermal treatment is accompanied by intensive CuO nanowhisker growth on the coating surface and the formation of the layered oxide phases (Cu{sub 2}O and CuO) in the coating interior. X-ray diffraction and focused ion beam (FIB) are employed to characterize the multilayer structure of annealed copper coatings. Formation of volumetric defects such as voids and cracks in the coating is demonstrated.

Film formation of non-planar phthalocyanines on copper(i) iodide

OpenAIRE

Ramadan, A. J.; Fearn, S.; Jones, T. S. (Tim S.); Heutz, S.; Rochford, L. A. (Luke A.)

2016-01-01

Structural templating is frequently used in organic photovoltaic devices to control the properties of the functional layers and therefore improve efficiencies. Modification of the substrate temperatures has also been shown to impact the structure and morphology of phthalocyanine thin films. Here we combine templating by copper iodide and high substrate temperature growth and study its effect on the structure and morphology of two different non-planar phthalocyanines, chloroaluminium (ClAlPc) ...

Critical review: Copper runoff from outdoor copper surfaces at atmospheric conditions.

Science.gov (United States)

Hedberg, Yolanda S; Hedberg, Jonas F; Herting, Gunilla; Goidanich, Sara; Odnevall Wallinder, Inger

2014-01-01

This review on copper runoff dispersed from unsheltered naturally patinated copper used for roofing and facades summarizes and discusses influencing factors, available literature, and predictive models, and the importance of fate and speciation for environmental risk assessment. Copper runoff from outdoor surfaces is predominantly governed by electrochemical and chemical reactions and is highly dependent on given exposure conditions (size, inclination, geometry, degree of sheltering, and orientation), surface parameters (age, patina composition, and thickness), and site-specific environmental conditions (gaseous pollutants, chlorides, rainfall characteristics (amount, intensity, pH), wind direction, temperature, time of wetness, season). The corrosion rate cannot be used to assess the runoff rate. The extent of released copper varies largely between different rain events and is related to dry and wet periods, dry deposition prior to the rain event and prevailing rain and patina characteristics. Interpretation and use of copper runoff data for environmental risk assessment and management need therefore to consider site-specific factors and focus on average data of long-term studies (several years). Risk assessments require furthermore that changes in copper speciation, bioavailability aspects, and potential irreversible retention on solid surfaces are considered, factors that determine the environmental fate of copper runoff from outdoor surfaces.

Copper hypersensitivity

DEFF Research Database (Denmark)

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

2014-01-01

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...

Graphitization of self-assembled monolayers using patterned nickel-copper layers

Science.gov (United States)

Yang, Gwangseok; Kim, Hong-Yeol; Kim, Jihyun

2017-07-01

Controlling the optical and electrical properties of graphene is of great importance because it is directly related to commercialization of graphene-based electronic and optoelectronic devices. The development of a spatially controlled layer-tunable and direct growth method is a favored strategy because it allows for the manipulation of the optical and electrical properties of graphene without complex processes. Here, patterned Ni on Cu layers is employed to achieve spatially thickness-tuned graphene because its thickness depends on the carbon solubility of catalytic metals. Transfer-free graphene is directly grown on an arbitrary target substrate by using self-assembled monolayers as the carbon source. The optical transmittance at a wavelength of 550 nm and the sheet resistance of graphene are adjusted from 65.0% and 2.33 kΩ/◻ to 85.8% and 7.98 kΩ/◻, respectively. Ambipolar behavior with a hole carrier mobility of 3.4 cm2/(V.s) is obtained from the fabricated device. Therefore, a spatially controlled layer-tunable and transfer-free growth method can be used to realize advanced designs for graphene-based optical and electrical devices.

Nanoscale characterization of martensite structures in copper based shape memory alloys

Energy Technology Data Exchange (ETDEWEB)

Adiguzel, O, E-mail: oadiguzel@firat.edu.t [Firat University Department of Physics, 23169 Elazig (Turkey)

2010-11-01

Martensitic transformations are first order displacive transitions and occur in the materials on cooling from high temperature. Shape memory effect is an unusual property exhibited by certain alloy systems, and leads to martensitic transition. Copper-based alloys exhibit this property in beta phase field which possess simple bcc- structures, austenite structure at high-temperatures. As temperature is lowered the austenite undergoes martensitic transition following two ordering reactions, and structural changes in nanoscale govern this transition. Atomic movements are also confined to interatomic lengths in sub-{mu}m or angstrom scale in martensitic transformation. The formation of the layered structures in copper based alloys consists of shears and shear mechanism. Martensitic transformations occur in a few steps with the cooperative movement of atoms less than interatomic distances by means of lattice invariant shears on a {l_brace}110{r_brace} - type plane of austenite matrix which is basal plane or stacking plane of martensite. The lattice invariant shears occurs, in two opposite directions, <110> -type directions on the {l_brace}110{r_brace}-type plane. These shears gives rise to the formation of layered structure.

Fabricating Copper Nanotubes by Electrodeposition

Science.gov (United States)

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.

Investigation of defects in ultra-thin Al{sub 2}O{sub 3} films deposited on pure copper by the atomic layer deposition technique

Energy Technology Data Exchange (ETDEWEB)

Chang, M.L.; Wang, L.C. [Department of Materials Science and Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan (China); Lin, H.C., E-mail: hclinntu@ntu.edu.tw [Department of Materials Science and Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan (China); Chen, M.J., E-mail: mjchen@ntu.edu.tw [Department of Materials Science and Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan (China); Lin, K.M. [Department of Materials Science and Engineering, Feng Chia University, No. 100, Wenhwa Road, Seatwen, Taichung 40724, Taiwan (China)

2015-12-30

Graphical abstract: Some residual OH ligands originating from incomplete reaction between TMA and surface species of OH* during ALD process induce the defects in deposited Al{sub 2}O{sub 3} films. Three possible types of defects are suggested. The analytic results indicate the defects are Type-I and/or Type-II but do not directly expose the substrate, like pinholes (Type-III). - Highlights: • Oxidation trials were conducted to investigate the defects in ultra-thin Al{sub 2}O{sub 3} films deposited ALD technique on pure copper. • The residual OH ligands in the deposited Al{sub 2}O{sub 3} films induce looser micro-structure which has worse oxidation resistance. • Superficial contamination particles on substrate surface are confirmed to be one of nucleation sites of the defects. - Abstract: Al{sub 2}O{sub 3} films with various thicknesses were deposited by the atomic layer deposition (ALD) technique on pure copper at temperatures of 100–200 °C. Oxidation trials were conducted in air at 200 °C to investigate the defects in these films. The analytic results show that the defects have a looser micro-structure compared to their surroundings, but do not directly expose the substrate, like pinholes. The film's crystallinity, mechanical properties and oxidation resistance could also be affected by these defects. Superficial contamination particles on the substrate surface are confirmed to be nucleation sites of the defects. A model for the mechanism of defect formation is proposed in this study.

Significant Improvement of Organic Thin-Film Transistor Mobility Utilizing an Organic Heterojunction Buffer Layer

International Nuclear Information System (INIS)

Pan Feng; Qian Xian-Rui; Huang Li-Zhen; Wang Hai-Bo; Yan Dong-Hang

2011-01-01

High-mobility vanadyl phthalocyanine (VOPc)/5,5‴-bis(4-fluorophenyl)-2,2':5',2″:5″,2‴-quaterthiophene (F2-P4T) thin-film transistors are demonstrated by employing a copper hexadecafluorophthalocyanine (F 16 CuPc)/copper phthalocyanine (CuPc) heterojunction unit, which are fabricated at different substrate temperatures, as a buffer layer. The highest mobility of 4.08cm 2 /Vs is achieved using a F 16 CuPc/CuPc organic heterojunction buffer layer fabricated at high substrate temperature. Compared with the random small grain-like morphology of the room-temperature buffer layer, the high-temperature organic heterojunction presents a large-sized fiber-like film morphology, resulting in an enhanced conductivity. Thus the contact resistance of the transistor is significantly reduced and an obvious improvement in device mobility is obtained. (cross-disciplinary physics and related areas of science and technology)

Surface characteristics, copper release, and toxicity of nano- and micrometer-sized copper and copper(II) oxide particles: a cross-disciplinary study.

OpenAIRE

Midander, Klara; Cronholm, Pontus; Karlsson, Hanna L.; Elihn, Karine; Moller, Lennart; Leygraf, Christofer; Wallinder, Inger Odnevall

2009-01-01

An interdisciplinary and multianalytical research effort is undertaken to assess the toxic aspects of thoroughly characterized nano- and micrometer-sized particles of oxidized metallic copper and copper(II) oxide in contact with cultivated lung cells, as well as copper release in relevant media. All particles, except micrometer-sized Cu, release more copper in serum-containing cell medium (supplemented Dulbecco's minimal essential medium) compared to identical exposures in phosphate-buffered ...

Investigation of Superficial Resistance of Different Purity Copper at Boiling Nitrogen Temperature Depending on Treatment of Current-Conducting Layer

International Nuclear Information System (INIS)

Kutovoj, V.A.; Nikolaenko, A.A.; Stoev, P.I.

2007-01-01

Results of this scientific work show influence of annealing temperature and deformation degree of initial MOB copper and after electron beam refining on superficial resistance at temperature of boiling nitrogen. It is shown, that 30 % deformation and annealing in 873...923 K temperature range results in appreciable reduction of superficial resistance at the investigated samples of copper. The lowest values of superficial resistance after thermal and mechanical treatment were observed in the samples after electron beam refinement

Binary molecular layers of C-60 and copper phthalocyanine on Au(111) : Self-organized nanostructuring

NARCIS (Netherlands)

Stöhr, Meike; Wagner, Thorsten; Gabriel, Markus; Weyers, Bastian; Möller, Rolf

The binary molecular system of C-60 and copper phthalocyanine(CuPc) molecules has been investigated by scanning tunneling microscopy (STM) at room temperature and at 50 K. As substrate Au(111) was chosen. When C-60 and CuPc molecules are sequentially deposited, it is found that well-ordered domains

Investigation on microstructure and thermal properties of in-situ synthesized Cu-ZrO2 nanocomposites

International Nuclear Information System (INIS)

Elmahdy, Marwa; Abouelmagd, Gamal; Mazen, Asaad A.

2017-01-01

Cu-ZrO 2 nanocomposites were prepared by an in-situ reactive synthesis of copper nitrate Cu(NO 3 ) 2 and zirconium oxychloride ZrOCl 2 . Zirconia (ZrO 2 ) was added by 2.5, 5 and 10 wt.% to the Cu matrix to assess its effect on thermal conductivity and thermal expansion behavior. The results showed that ZrO 2 nanoparticles (30-50 nm) were homogeneously distributed in the copper matrix. The measured thermal conductivity for the Cu-ZrO 2 nanocomposites decreased from 372.8 to 94.4 W m -1 K -1 with increasing ZrO 2 content from 0 to 10 wt.%. Cu-10 wt.% ZrO 2 nanocomposite yields a low thermal conductivity of 94.4 W . m -1 K -1 along with a low coefficient of thermal expansion, 11.47 x 10 -6 K -1 .

Electrochemical in-situ impregnation of wood using a copper nail as source for copper

DEFF Research Database (Denmark)

Ottosen, Lisbeth M.; Block, Thomas; Nymark, Morten

2011-01-01

A new method for copper impregnation of wood in structures was suggested and tested in laboratory scale with specimen of new pine sapwood. A copper nail and a steel screw were placed in the wood, and an electric direct current field was applied, so the copper nail was anode and the screw...... was cathode. At the anode, copper ions were generated. The copper ions were transported into the wood by electromigration (movement of ions in an applied electric field) towards the cathode, and a volume between the two electrodes was thereby impregnated. Copper also moved to a lesser degree in the opposite...

Fungicides and silicate clay on the control of antracnosis in yellow passionfruitFungicidas e argila silicatada no controle da antracnose do maracujá amarelo

Directory of Open Access Journals (Sweden)

Luiz Augusto Martins Peruch

2012-10-01

Full Text Available The anthracnose, caused by Glomerella cingulata (anamorf Colletotrichum gloeosporioides, is the most important fungal disease for aerial parts of yellow passionfruit. However, few studies about anthracnose control in field conditions have been published. The objective of this research was to evaluate silicate clay and fungicides for anthracnose control. Treatments evaluated were: tebuconazole (20g i.a./100L, copper oxychloride (180g i.a./100L, silicate clay (15g /L and control (untreated plants. The sanity of the plants was evaluated through area under disease progress curve (AUCPD, final severity (SEVF and disease progress curves. Experimental design was completely randomized with five repetitions. Tebuconazole and silicate clay proportioned significant reduction for AUCPD and SEVF compared to control. Copper oxychloride reduced only SEVF. Treatment with tebuconazole reduced AUCPD and SEVF in 75% and 71%, and silicate clay in 82%, respectively. Copper oxychloride reduced SEVF in 76%. The disease progress curves confirmed results and showed lower growth of anthracnose for tebuconazole and silicate clay. Silicate clay and tebuconazole are efficient to control anthracnose in passionfruit. A antracnose, causada por Glomerella cingulata (anamorfo Colletotrichum gloesporioides, é a principal doença fúngica de parte aérea do maracujazeiro amarelo. Todavia, poucos estudos de controle da doença a campo têm sido publicados, motivo pelo qual é importante avaliar diferentes fungicidas e substâncias alternativas para o manejo da antracnose. Neste trabalho foram avaliados os seguintes tratamentos: tebuconazole (20g i.a./100L, oxicloreto de cobre (180g i.a./100L, argila silicatada (15g /L e testemunha. A partir da avaliação da severidade da doença, determinou-se a área abaixo da curva de progresso da doença (AACPD, severidade final (SEVF e as curvas de progresso da doença. O delineamento adotado foi inteiramente casualizado com cinco repeti

Strength-limited magnetic field intensity of toroidal magnet systems fabricated or the base of layer-by-layer shrouded solenoids

International Nuclear Information System (INIS)

Litvinnko, Yu.A.

1982-01-01

The possibilities, as to the ultimate magnetic field strength, of tokamak magnet systems made on the base of layer-by-laeyer shrouded coils are considered numerically. The toroidal magnet system is considered which consists of N skewe, layer-by-layer shrouded, equistrong coils in the ideal torus approximation. The dependences of the ragnetic field strength on the internal- and external torus radii, pulse duration and aspect ratio for copper coils shrouded with fiberglass are calculated as an example. The analysis of the obtained results shows that using of the layer-by-layer shrouding scheme for toroidal solenoid coils leads to a considerable growth of the ultimate magnetic field strengths in a wide duration range. For example, the limiting field strength along the toroidal solenoid axis of the considered type inside the ''FT'' installation toroidal solenoid at equivalent field pulse duration of approximately 0.3 s reaches H 0 =1.3zx10 7 A/m

Copper Leaching from Copper-ethanolamine Treated Wood: Comparison of Field Test Studies and Laboratory Standard Procedures

OpenAIRE

Nejc Thaler; Miha Humar

2014-01-01

Copper-based compounds are some of the most important biocides for the protection of wood in heavy duty applications. In the past, copper was combined with chromium compounds to reduce copper leaching, but a recent generation of copper-based preservatives uses ethanolamine as a fixative. To elucidate the leaching of copper biocides from wood, Norway spruce (Picea abies) wood was treated with a commercial copper-ethanolamine solution with two different copper concentrations (cCu = 0.125% and 0...

Selective Laser Melting of Pure Copper

Science.gov (United States)

Ikeshoji, Toshi-Taka; Nakamura, Kazuya; Yonehara, Makiko; Imai, Ken; Kyogoku, Hideki

2018-03-01

Appropriate building parameters for selective laser melting of 99.9% pure copper powder were investigated at relatively high laser power of 800 W for hatch pitch in the range from 0.025 mm to 0.12 mm. The highest relative density of the built material was 99.6%, obtained at hatch pitch of 0.10 mm. Building conditions were also studied using transient heat analysis in finite element modeling of the liquidation and solidification of the powder layer. The estimated melt pool length and width were comparable to values obtained by observations using a thermoviewer. The trend for the melt pool width versus the hatch pitch agreed with experimental values.

Copper metabolism: a multicompartmental model of copper kinetics in the rat

International Nuclear Information System (INIS)

Dunn, M.A.

1985-01-01

A qualitative multicompartmental model was developed that describes the whole-body kinetics of copper metabolism in the adult rat. The model was developed from radiocopper percent dose vs. time data measured over a three day period in plasma, liver, skin, skeletal muscle, bile and feces after the intravenous injection of 10 μg copper labeled with 64 Cu. Plasma radiocopper was separated into ceruloplasmin (Cp) and nonceruloplasmin (NCp) fractions. Liver cytosolic radiocopper was fractionated into void volume superoxide dismutase (SOD) containing and metallothionein fractions by gel filtration. Liver particulate fractions were isolated by differential centrifugation. The SAAM and CONSAM modeling programs were used to develop the model. The sizes of compartments, fractional rate constants and mass transfer rates between compartments were evaluated. The intracellular metabolism of copper was similar in hepatic and extrahepatic tissues being comprised of a faster turning over compartment (FTC) exchanging copper with NCp and a slower turning over compartment (STC) with input from Cp. Output from the STC was into the FTC. In the liver the STC was postulated to represent SOD copper which unlike the extrahepatic tissues received much of its input from the FTC. A small amount of biliary copper (9%) was postulated to return to plasma NCp by enterohepatic recycling. The model developed was contrasted and compared with two previous models of copper metabolism

Copper spherical cavity arrays: Fluorescence enhancement in PFO films

Energy Technology Data Exchange (ETDEWEB)

Spada, Edna R., E-mail: edspada@gmail.com [Instituto de Física de São Carlos, Universidade de São Paulo, Caixa Postal 369, 13560-970, São Carlos, SP (Brazil); Valente, Gustavo T.; Pereira-da-Silva, Marcelo A. [Instituto de Física de São Carlos, Universidade de São Paulo, Caixa Postal 369, 13560-970, São Carlos, SP (Brazil); Sartorelli, Maria L. [Departamento de Física, Universidade Federal de Santa Catarina, Caixa Postal 476, 88040-900, Florianópolis, SC (Brazil); Guimarães, Francisco E.G.; Faria, Roberto M. [Instituto de Física de São Carlos, Universidade de São Paulo, Caixa Postal 369, 13560-970, São Carlos, SP (Brazil)

2017-01-15

This manuscript addresses the use of a well-ordered antidot copper nanostructure as a active substrate for surface enhancement fluorescence (SEF). The antidot array was produced by electrodeposition and nanosphere lithography and characterized by microscopy technique, its successful application as SEF-active substrates was verified using polyfluorene (PFO) as a probe layer. Atomic force microscopy (AFM) was used to evaluate the regularity of the metal surface as well PFO coated process and confocal laser fluorescence microscopy (CLSM) to determine the behavior exhibited by the fluorescent layer due to the existence of the nanostructured surface. No accumulation PFO in the cavities was detected and the more intense emission regions coincides with the position of the cavities and is at about one order of magnitude higher.

The effect of composition on volatility from a copper alloy

International Nuclear Information System (INIS)

McCarthy, K.A.; Smolik, G.R.; Wallace, R.S.

1994-01-01

During a Loss of Coolant Accident (LOCA) activated structural material can be mobilized through oxidation. Information on how much material is mobilized in an accident is necessary for performing safety assessments of fusion reactor designs. The Fusion Safety Program at the Idaho National Engineering Laboratory has an experimental program to measure mobilized mass as a function of temperature for various oxidizing environments. Materials studied have included beryllium (important because of its toxicity), copper alloys, a niobium alloy, PCA and HT-9 steel, tungsten (pure and an alloy), and a vanadium alloy. Some materials undergo a significant change in composition during irradiation. An example of this is copper (a candidate for the ITER first wall, divertor substrate, and various instrumentation probes and antennas), which can have as much as 1 wt% zinc due to transmutation. Additionally, as the design for ITER evolves, a slightly different copper alloy may be selected. Compositional changes may affect the extent that various elements are volatilized due to such mechanisms as diffusion through the alloy, and penetration and release from oxide layers formed on the material. To accurately calculate offsite doses for various irradiation scenarios, one must understand the effect of composition on volatility

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

Science.gov (United States)

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.

Ag2CuMnO4: A new silver copper oxide with delafossite structure

International Nuclear Information System (INIS)

Munoz-Rojas, David; Subias, Gloria; Oro-Sole, Judith; Fraxedas, Jordi; Martinez, Benjamin; Casas-Cabanas, Montse; Canales-Vazquez, Jesus; Gonzalez-Calbet, Jose; Garcia-Gonzalez, Ester; Walton, Richard I.; Casan-Pastor, Nieves

2006-01-01

The use of hydrothermal methods has allowed the synthesis of a new silver copper mixed oxide, Ag 2 CuMnO 4 , the first example of a quaternary oxide containing both elements. It crystallizes with the delafossite 3R structure, thus being the first delafossite to contain both Ag and Cu. Synthesis conditions affect the final particle size (30-500nm). Powder X-ray diffraction Rietveld refinement indicates a trigonal structure (R3-bar m) and cell parameters a=2.99991A and c=18.428A, where Cu and Mn are disordered within the octahedral B positions in the plane and linearly coordinated Ag occupies de A position between layers. X-ray absorption near edge spectroscopy (XANES) for copper and manganese, and XPS for silver evidence +2, +4, and +1 oxidation states. The microstructure consists of layered particles that may form large twins showing 5nm nanodomains. Finally, magnetic measurements reveal the existence of ferromagnetic coupling yielding in-plane moments that align antiferromagnetically at lower temperatures. The singularity of the new phase resides on the fact that is an example of a bidimensional arrangement of silver and copper in an oxide that also shows clear bidimensionality in its physical properties. That is of special relevance to the field of high T c superconducting oxides, while the ferromagnetic coupling in a bidimensional system deserves itself special attention

XRF measurements of tin, copper and zinc in antifouling paints coated on leisure boats

International Nuclear Information System (INIS)

Ytreberg, Erik; Bighiu, Maria Alexandra; Lundgren, Lennart; Eklund, Britta

2016-01-01

Tributyltin (TBT) and other organotin compounds have been restricted for use on leisure boats since 1989 in the EU. Nonetheless, release of TBT is observed from leisure boats during hull maintenance work, such as pressure hosing. In this work, we used a handheld X-ray Fluorescence analyser (XRF) calibrated for antifouling paint matrixes to measure tin, copper and zinc in antifouling paints coated on leisure boats in Sweden. Our results show that over 10% of the leisure boats (n = 686) contain >400 μg/cm 2 of tin in their antifouling coatings. For comparison, one layer (40 μm dry film) of a TBT-paint equals ≈ 800 μg Sn/cm 2 . To our knowledge, tin has never been used in other forms than organotin (OT) in antifouling paints. Thus, even though the XRF analysis does not provide any information on the speciation of tin, the high concentrations indicate that these leisure boats still have OT coatings present on their hull. On several leisure boats we performed additional XRF measurements by progressively scraping off the top coatings and analysing each underlying layer. The XRF data show that when tin is detected, it is most likely present in coatings close to the hull with several layers of other coatings on top. Thus, leaching of OT compounds from the hull into the water is presumed to be negligible. The risk for environmental impacts arises during maintenance work such as scraping, blasting and high pressure hosing activities. The data also show that many boat owners apply excessive paint layers when following paint manufacturers recommendations. Moreover, high loads of copper were detected even on boats sailing in freshwater, despite the more than 20 year old ban, which poses an environmental risk that has not been addressed until now. - Highlights: • A new XRF application for analysing metals in antifouling paints has been used. • Almost 700 leisure boats were analysed for tin, copper and zinc. • Over 10% of the leisure boats contained high, >400�

Renal cortex copper concentration in acute copper poisoning in calves

Directory of Open Access Journals (Sweden)

Luis E. Fazzio

2012-01-01

Full Text Available The aim of this study was to estimate the diagnostic value of renal cortex copper (Cu concentration in clinical cases of acute copper poisoning (ACP. A total of 97 calves that died due to subcutaneous copper administration were compiled in eleven farms. At least, one necropsy was conducted on each farm and samples for complementary analysis were taken. The degree of autolysis in each necropsy was evaluated. The cases appeared on extensive grazing calf breeding and intensive feedlot farms, in calves of 60 to 200 kg body weight. Mortality varied from 0.86 to 6.96 %, on the farms studied. The first succumbed calf was found on the farms between 6 and 72 hours after the susbcutaneous Cu administration. As discrepancies regarding the reference value arose, the local value (19.9 parts per million was used, confirming the diagnosis of acute copper poisoning in 93% of the analyzed kidney samples. These results confirm the value of analysis of the cortical kidney Cu concentration for the diagnosis of acute copper poisoning.

The Copper Substrate Developments for the HIE-ISOLDE High-Beta Quarter Wave Resonator

CERN Document Server

Alberty, L; Aviles, I; Calatroni, S; Capatina, O; Foffano, G; Kadi, Y; Moyret, P; Schirm, K-M; Tardy, T; Venturini Delsolaro, W; D'Elia, A

2013-01-01

A new Linac using superconducting Quarter-Wave Resonators (QWRs) is under construction at CERN in the framework of the HIE-ISOLDE project. The QWRs are made by niobium sputtered on a bulk copper substrate. The working frequency at 4.5 K is 101.28 MHz and they will provide 6 MV/m accelerating gradient on the beam axis with a total maximum power dissipation of 10 W. The properties of the cavity substrate have a direct impact on the final cavity performance. The copper substrate has to ensure an optimum surface for the niobium sputtered layer. It has also to fulfil the required geometrical tolerances, the mechanical stability during operation and the thermal performance to optimally extract the RF dissipated power on cavity walls. The paper presents the mechanical design of the high β cavities. The procurement process of the copper raw material is detailed, including specifications and tests. The manufacturing sequence of the complete cavity is then explained and the structural and thermo-mechanical behaviour...

Morphology of micro- and nanoparticles emitted by copper plants in Western Poland

Energy Technology Data Exchange (ETDEWEB)

Konarski, P.; Cwil, M.; Iwanejko, I.; Mierzejewska, A.; Diduszko, R

2004-07-01

Aerosol particles were collected in the vicinity of copper plants in Western Poland and analysed by mass spectrometry methods like secondary ion mass spectrometry (SIMS), spark source mass spectrometry (SSMS) and X-ray diffraction to characterise the possible dangers for the environment and health. The motivation of the work was to approach the toxicological mechanisms that are triggered when aerosol nanoparticles enter the human body. Different analytical techniques were used in order to compare bulk and surface properties of particles. The particle collection was performed with nine-stage cascade impactor with rotating plates and also with micro-fibre quartz filter collector. SSMS bulk analysis of copper plant emitted particles shows the presence of over 30 elements, the concentration in wt.% of Cu, Pb, Zn and Cl is 30, 5, 2 and 1, respectively. XRD analysis of these particles shows crystalline phases of quartz and probable phases containing copper CuS{sub 2}, lead Pb{sub 2}SiO{sub 4}, PbO - massicot, Pb{sub 5}[OH][PO{sub 4}]{sub 3}, Pb{sub 3}SiO{sub 5}, iron and calcium Ca[Mg{sub 0.67}Fe{sub 0.33}][CO{sub 3}] - dolomite, ferroan, Ca[FeMg][CO{sub 3}]{sub 2} - ankerite, Ca[MgFe]Si{sub 2}O{sub 6} - augite. Surface sensitive SIMS depth profile analysis revealed the core-shell structure of copper plant emitted particles. The obtained structure of these particles shows that surfaces of the particles are enriched in elements like chlorine, fluorine, lead and chromium with respect to the core concentrations of these elements. The cores are composed mainly of copper, oxygen and carbon containing compounds. Lead concentration is nearly two times greater at the surface layers of particles than in the cores. SIMS analysis of urban aerosol particles collected in Legnica shows compositional dependence with size. Surface shell layer concentration of lead is three times greater for coarse 6-15 {mu}m particles than for tiny 300 nm-1 {mu}m particles. Such non-uniform particle

Preparation of copper and silicon/copper powders by a gas ...

Indian Academy of Sciences (India)

Administrator

aCentre for Materials Research, Department of Imaging and Applied Physics, ... Copper powder; Si/Cu composite particle; gas evaporation–condensation method; characteriza- tion. .... from the liquid metal surface, the mixed vapour of copper.

Posttranslational regulation of copper transporters

NARCIS (Netherlands)

van den Berghe, P.V.E.

2009-01-01

The transition metal copper is an essential cofactor for many redox-active enzymes, but excessive copper can generate toxic reactive oxygen species. Copper homeostasis is maintained by highly conserved proteins, to balance copper uptake, distribution and export on the systemic and cellular level.

Rare earth phosphors and phosphor screens

International Nuclear Information System (INIS)

Buchanan, R.A.; Maple, T.G.; Sklensky, A.F.

1981-01-01

Advances in the use of stabilized rare earth phosphors and of conversion screens using these materials are examined. In particular the new phosphors discussed in this invention consist of oxybromides of yttrium, lanthanum and gadolinium with a luminescent activator ion stabilized by an oxychloride or oxyfluoride surface layer and the conversion screens include trivalent cerium as the activator ion. (U.K.)

RECYCLING OF SCRAP AND WASTE OF COPPER AND COPPER ALLOYS IN BELARUS

Directory of Open Access Journals (Sweden)

S. L. Rovin

2017-01-01

Full Text Available The construction of a new casting and mechanical shop of unitary enterprise «Tsvetmet» in December 2015 has allowed to solve the complex problem of processing and utilization of scrap and wastes of copper and copper alloys in the Republic of Belarus. The technological processes of fire refinement of copper and manufacturing of copper rod from scrap and production of brass rod by hot pressing (extrusion of the continuously casted round billet have been mastered for the first time in the Republic of Belarus.

Real-time oxide evolution of copper protected by graphene and boron nitride barriers

DEFF Research Database (Denmark)

Galbiati, Miriam; Stoot, Adam Carsten; Mackenzie, David

2017-01-01

and material science. Owing to their different electronic properties (graphene is a semimetal, whereas hBN is a wide-bandgap insulator), their protection behaviour is distinctly different. Here we investigate the performance of graphene and hBN as barrier coatings applied on copper substrates through a real......-time study in two different oxidative conditions. Our findings show that the evolution of the copper oxidation is remarkably different for the two coating materials.......Applying protective or barrier layers to isolate a target item from the environment is a common approach to prevent or delay its degradation. The impermeability of two-dimensional materials such as graphene and hexagonal boron nitride (hBN) has generated a great deal of interest in corrosion...

Real-time oxide evolution of copper protected by graphene and boron nitride barriers.

Science.gov (United States)

Galbiati, M; Stoot, A C; Mackenzie, D M A; Bøggild, P; Camilli, L

2017-01-09

Applying protective or barrier layers to isolate a target item from the environment is a common approach to prevent or delay its degradation. The impermeability of two-dimensional materials such as graphene and hexagonal boron nitride (hBN) has generated a great deal of interest in corrosion and material science. Owing to their different electronic properties (graphene is a semimetal, whereas hBN is a wide-bandgap insulator), their protection behaviour is distinctly different. Here we investigate the performance of graphene and hBN as barrier coatings applied on copper substrates through a real-time study in two different oxidative conditions. Our findings show that the evolution of the copper oxidation is remarkably different for the two coating materials.

Demystifying Controlling Copper Corrosion

Science.gov (United States)

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...

Copper Bioleaching in Chile

OpenAIRE

Juan Carlos Gentina; Fernando Acevedo

2016-01-01

Chile has a great tradition of producing and exporting copper. Over the last several decades, it has become the first producer on an international level. Its copper reserves are also the most important on the planet. However, after years of mineral exploitation, the ease of extracting copper oxides and ore copper content has diminished. To keep the production level high, the introduction of new technologies has become necessary. One that has been successful is bioleaching. Chile had the first...

A study on structure and tribological properties of the electroerosion coating Mo-Ni-Cu, formed by the mixed method on copper

Science.gov (United States)

Romanov, D. A.; Goncharova, E. N.; Gromov, V. E.; Ivanov, Yu F.

2016-09-01

Multi-layered coating from immiscible components based on the system Mo-Ni-Cu was formed by the combined method of electro-explosive sputtering and subsequent irradiation by high-intensity pulse electron beam of submillisecond duration of influence on the surface of electrical copper contact (M00 grade of copper). The structure and phase composition studies of the applied coating as well as its mechanical and tribological properties are carried out.

Review of supercontainer copper shell-bentonite interactions and possible effects on buffer performance for the KBS-3H design

International Nuclear Information System (INIS)

King, F.; Wersin, P.

2014-03-01

A review is presented of the possible impact of the corrosion of a copper supercontainer shell on the performance of the bentonite buffer. The review is presented in two parts; first an assessment of the likely corrosion behaviour of the copper shell, including an assessment of the amount and speciation of copper corrosion products, and, second an assessment of the possible interactions of these copper corrosion products with the bentonite and the consequences for the buffer performance. The corrosion behaviour of oxygen-free copper in compacted bentonite is reviewed, including the effects of a possible lower-density region at the buffer-rock interface initially. Corrosion occurs under both aerobic conditions, due to the initial O 2 trapped in the bentonite and O 2 in the air or water-filled gap at the buffer/rock interface, and anaerobic conditions, due to sulphide present in the groundwater and that possibly produced by microbial activity in the bentonite. The reaction mechanism, the nature of the dissolved and precipitated corrosion products, and the evolution of the corrosion behaviour with time are discussed with reference to groundwater conditions at both Olkiluoto and Forsmark. Various interactions between the copper corrosion products (Cu(II) and Cu(I) species) and bentonite are considered, including diffusion and sorption and the incorporation of Cu into the bentonite. The available literature information on these processes is first reviewed and then this knowledge is used to predict the likely behaviour in a KBS-3H-style repository. Based on the information currently available, it is concluded that the corrosion of a copper supercontainer shell will only affect the bentonite within a distance of a few cm of the original location of the shell. Eventually, the copper shell will corrode to form an insoluble precipitate layer of Cu 2 S approximately 2-3 times the volume of the original shell. Bentonite within a few cm of this layer of precipitate may also

Experiences with electrochemical analysis of copper at the PPB-level in saline cooling water and in the water/steam cycle

Energy Technology Data Exchange (ETDEWEB)

Thomsen, K [I/S Nordjyllandsvaerket, Vodskov (Denmark)

1996-12-01

Determination of trace amounts of copper in saline cooling water and in process water by differential pulse anodic stripping voltammetry combined with an UV-photolysis pretreatment is described. Copper concentrations well below 1 {mu}g/L may be analysed with a precision in the order of 10% and a high degree of accuracy. The basic principles of the method are described together with three applications covering analysis of cooling and process water samples. The analysis method has been applied to document the adherence of environmental limits for the copper uptake of cooling water passing brass condensers, to monitor the formation of protective layers of iron oxides on the cooling water side of brass condensers, and to study the transport of copper in water/steam cycles with heat exchangers and condensers of brass materials. (au)

The copper-transporting ATPase pump and its potential role in copper-tolerance

Science.gov (United States)

Katie Ohno; C.A. Clausen; Frederick Green; G. Stanosz

2016-01-01

Copper-tolerant brown-rot decay fungi exploit intricate mechanisms to neutralize the efficacy of copper-containing preservative formulations. The production and accumulation oxalate is the most widely recognized theory regarding the mechanism of copper-tolerance in these fungi. The role of oxalate, however, may be only one part of a series of necessary components...

Copper complexing ligands and organic matter characterization in the northern Adriatic Sea

Science.gov (United States)

Plavšić, Marta; Gašparović, Blaženka; Strmečki, Slađana; Vojvodić, Vjeročka; Tepić, Nataša

2009-11-01

The study on dissolved organic ligands capable to complex copper ions (L T), surface-active substances (SAS) and dissolved organic carbon (DOC) in the Northern Adriatic Sea station (ST 101) under the influence of Po River was conducted in period from 2006-2008. The acidity of surface-active organic material (Ac r) was followed as well. The results are compared to temperature and salinity distributions. On that way, the contribution of the different pools of ligands capable to complex Cu ions could be determined as well as the influence of aging and transformation of the organic matter. The L T values in the investigated period were in the range of 40-300 nmol l -1. The range of DOC values for surface and bottom samples were 0.84-1.87 mg l -1 and 0.80-1.30 mg l -1, respectively. Total SAS concentrations in the bottom layer were 0.045-0.098 mg l -1 in equiv. of Triton-X-100 while those in the surface layer were 0.050-0.143 mg l -1 in equiv. of Triton-X-100. The majority of organic ligands responsible for Cu binding in surface water originate from new phytoplankton production promoted by river borne nutrients. Older, transformed organic matter, possessing higher relative acidity, is the main contributor to the pool of organic ligands that bind copper in the bottom samples. It was estimated that ˜9% of DOC in surface samples and ˜12% of DOC in the bottom samples are present as ligands capable to complex copper ions.

Calculation of angular distribution of 662 keV gamma rays by Monte Carlo method in copper medium

International Nuclear Information System (INIS)

Kahraman, A.; Ozmutlu, E.N.; Gurler, O.; Yalcin, S.; Kaynak, G.; Gundogdu, O.

2009-01-01

This paper presents results on the angular distribution of Compton scattering of 662 keV gamma photons in both forward and backward hemispheres in copper medium. The number of scattered events graph has been determined for scattered gamma photons in both the forward and backward hemispheres and theoretical saturation thicknesses have been obtained using these results. Furthermore, response function of a 51x51 mm NaI(Tl) detector at 60 deg. angle with incoming photons scattered from a 10 mm thick copper layer has been determined using Monte Carlo method.

Calculation of angular distribution of 662 keV gamma rays by Monte Carlo method in copper medium

Energy Technology Data Exchange (ETDEWEB)

Kahraman, A.; Ozmutlu, E.N. [Physics Department, Faculty of Arts and Sciences, Uludag University, Gorukle Campus, 16059 Bursa (Turkey); Gurler, O. [Physics Department, Faculty of Arts and Sciences, Uludag University, Gorukle Campus, 16059 Bursa (Turkey)], E-mail: ogurler@uludag.edu.tr; Yalcin, S. [Kastamonu University, Education Faculty, 37200 Kastamonu (Turkey); Kaynak, G. [Physics Department, Faculty of Arts and Sciences, Uludag University, Gorukle Campus, 16059 Bursa (Turkey); Gundogdu, O. [NCCPM, Medical Physics, Royal Surrey County, Hospital, GU2 7XX (United Kingdom); University of Kocaeli, Umuttepe Campus, 41100 Kocaeli (Turkey)

2009-12-15

This paper presents results on the angular distribution of Compton scattering of 662 keV gamma photons in both forward and backward hemispheres in copper medium. The number of scattered events graph has been determined for scattered gamma photons in both the forward and backward hemispheres and theoretical saturation thicknesses have been obtained using these results. Furthermore, response function of a 51x51 mm NaI(Tl) detector at 60 deg. angle with incoming photons scattered from a 10 mm thick copper layer has been determined using Monte Carlo method.

Dielectric material in lead-based perovskite and fabrication process for multilayer ceramic capacitor with copper internal electrode

International Nuclear Information System (INIS)

Kato, J.; Yokotani, Y.; Kagata, H.; Nakatani, S.; Kugimiya, K.

1990-01-01

This paper reports on the development of a multilayer ceramic capacitor with copper internal electrodes. Dielectric materials of the capacitor is lead- based perovskite (Pb a Ca b ) (Mg 1/3 Nb 2/3 ) x Ti y (Ni 1/2 W 1/2 ) z O 2 + a + b where a + b gt 1 and x + y + z = 1. The materials can be fired below 1000 degrees C and have high resistivity even when fired in the atmosphere below the equilibrium oxygen partial pressure of copper and CuO. The fabrication process of the capacitor has following features. The electrode paste is composed of copper oxide to prevent breaking of the laminated body in a burn out process. Then the copper oxide is first metalized and fired in a controlled atmosphere. The obtained capacitor of 20 dielectric layers of 17 micron meter meets to Z5U specification and has low loss tangent of 0.6% and stability under d.c. bias voltage and high a.c. field

Conductivity of laser printed copper structures limited by nano-crystal grain size and amorphous metal droplet shell

International Nuclear Information System (INIS)

Winter, Shoshana; Zenou, Michael; Kotler, Zvi

2016-01-01

We present a study of the morphology and electrical properties of copper structures which are printed by laser induced forward transfer from bulk copper. The percentage of voids and the oxidation levels are too low to account for the high resistivities (∼4 to 14 times the resistivity of bulk monocrystalline copper) of these structures. Transmission electron microscope (TEM) images of slices cut from the printed areas using a focused ion beam (FIB) show nano-sized crystal structures with grain sizes that are smaller than the electron free path length. Scattering from such grain boundaries causes a significant increase in the resistivity and can explain the measured resistivities of the structures. The TEM images also show a nano-amorphous layer (∼5 nm) at the droplet boundaries which also contributes to the overall resistivity. Such morphological characteristics are best explained by the ultrafast cooling rate of the molten copper droplets during printing. (paper)

Copper Hugoniot measurements to 2.8 TPa on Z.

Energy Technology Data Exchange (ETDEWEB)

Furnish, Michael D.; Haill, Thomas A

2018-04-01

We conducted three Hugoniot and release experiments on copper on the Z machine at Hugoniot stress levels of 0.34 and 2.6 TPa, using two-layer copper/aluminum impactors travelling at 8 and 27 km/s and Z-quartz windows. Velocity histories were recorded for 4 samples of different thicknesses and 5 locations on the flyer plate (3 and 4 for the first two experiments). On-sample measurements provided Hugoniot points (via transit time) and partial release states (via Z-quartz wavespeed). Fabrication of the impactor required thick plating and several diamond-machining steps. The lower-pressure test was planned as a 2.5 TPa test, but a failure on the Z machine degraded its performance; however, these results corroborated earlier Cu data in the same stress region. The second test suffered from significant flyer plate bowing, but the third did not. The Hugoniot data are compared with the APtshuler/Nellis nuclear-driven data, other data from Z and elsewhere, and representative Sesame models.

Raman spectroscopic studies of the interaction of oxalic acid and sodium oxalate used as corrosion inhibitors with copper

Science.gov (United States)

Jeziorowski, H.; Moser, B.

1985-09-01

The Raman spectra of the liquid-solid interface recorded in situ show the formation of a salt complex of the inhibitor molecules and the copper ions. This suggests that this chemisorbed surface species produces the protective layer.

Use of copper radioisotopes in investigating disorders of copper metabolism

International Nuclear Information System (INIS)

Camakaris, J.; Voskoboinik, I.; Brooks, H.; Greenough, M.; Smith, S.; Mercer, J.

1998-01-01

Full text: Copper is an essential trace element for life as a number of vital enzymes require it. Copper deficiency can lead to neurological disorders, osteoporosis and weakening of arteries. However Cu is also highly toxic and homeostatic mechanisms have evolved to maintain Cu at levels which satisfy requirements but do not cause toxicity. Toxicity is mediated by the oxidative capacity of Cu and its ability to generate toxic free radicals. There are several acquired and inherited diseases due to either Cu toxicity or Cu deficiency. The study of these diseases facilitates identification of genes and proteins involved in copper homeostasis, and this in turn will provide rational therapeutic approaches. Our studies have focused on Menkes disease in humans which is an inherited and usually lethal copper deficiency. Using copper radioisotopes 64 Cu (t 1/2 = 12.8 hr) and 67 Cu (t 1/2 = 61 hr) we have studied the protein which is mutated in Menkes disease. This is a transmembrane copper pump which is responsible for absorption of copper into the body and also functions to pump out excess Cu from cells when Cu is elevated. It is therefore a vital component of normal Cu homeostasis. We have provided the first biochemical evidence that the Menkes protein functions as a P-type ATPase Cu pump (Voskoboinik et al., FEBS Letters, in press) and these data will be discussed. The assay involved pumping of radiocopper into purified membrane vesicles. Furthermore we have transfected normal and mutant Menkes genes into cells and are carrying out structure-function studies. We are also studying the role of amyloid precursor protein (APP) as a Cu transport protein in order to determine how Cu regulates this protein and its cleavage products. These studies will provide vital information on the relationship between Cu and APP and processes which lead to Alzheimers disease

Recovery of Copper from Copper Slag by Hydrometallurgy Method, from Iraqi Factories Waste

Directory of Open Access Journals (Sweden)

Bahaa Sami Mahdi

2018-05-01

Full Text Available   In this research, the recovery of copper from copper slag is investigated using hydrometallurgy method. Slag samples were taken from Al-Shaheed State Company. The results of the chemical analysis showed that the slag contained 11.4% of copper. The recovery process included two stages; the first stage is leaching using diluted sulfuric acid. The most important variables that effect on the leaching process was studied, such as acid concentration, hydrogen peroxide adding, particle size, liquid to solid, stirring speed and leaching time by changing the condition and the stabilizing of other factors at room temperature.               The second stage is precipitation of copper from leaching solution by zinc powder with different weights and times, at room temperature and 1.5 PH value. The results of the first stage manifested that about 99.7% of the copper have been dissolved at the following operational conditions: 50% acid concentration, 5 ml hydrogen peroxide adding, particle size (-75+53 micron, 1:10 liquid to solid, 500 rpm stirring speed and 25 min of leaching time. The highest percentage of copper precipitation in the second stage was 99.8% when added 3gm zinc powder at 20 min. The XRD result revealed that the predominant phase was pure copper. The results of EDS exhibited that a few percentage of oxygen appeared with copper powder. The final of copper recovery ratio was 99.3% with 99.2% purity.

Bacterial Killing by Dry Metallic Copper Surfaces▿

OpenAIRE

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

2010-01-01

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 fir...

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

Science.gov (United States)

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

Current trends in copper theft prevention

Energy Technology Data Exchange (ETDEWEB)

Mastrofrancesco, A. [Electrical Safety Authority, ON (Canada)

2009-07-01

Copper is used in electrical wiring, water and gas piping, currency, and in household items. An increase in the price and demand for copper has made copper theft a profitable venture for some thieves. Copper consumed in North America is typically supplied by recycling. Scrap dealers may pay near-market prices for pure copper wires. However, copper theft poses a serious threat to the safety of utility workers and the public. Power outages caused by copper theft are now affecting grid reliability. This paper examined technologies and techniques used to prevent copper theft as part of a security strategy for utilities. Attempts to steal copper can leave utility substations unsecured and accessible to children. The theft of neutral grounds will cause the local distribution company (LDC) to malfunction and may cause power surges in homes as well as appliance fires. Utilities are now looking at using a hybrid steel and copper alternative to prevent copper theft. Asset identification techniques are also being used to identify the original owners of the copper and more easily prosecute thieves. Automated monitoring techniques are also being used to increase substation security. Utilities are also partnering with law enforcement agencies and pressuring governments to require scrap dealers to record who they buy from. It was concluded that strategies to prevent copper theft should be considered as part of an overall security strategy for utilities. tabs., figs.

Copper Recovery from Yulong Complex Copper Oxide Ore by Flotation and Magnetic Separation

Science.gov (United States)

Han, Junwei; Xiao, Jun; Qin, Wenqing; Chen, Daixiong; Liu, Wei

2017-09-01

A combined process of flotation and high-gradient magnetic separation was proposed to utilize Yulong complex copper oxide ore. The effects of particle size, activators, Na2S dosage, LA (a mixture of ammonium sulfate and ethylenediamine) dosage, activating time, collectors, COC (a combination collector of modified hydroxyl oxime acid and xanthate) dosage, and magnetic intensity on the copper recovery were investigated. The results showed that 74.08% Cu was recovered by flotation, while the average grade of the copper concentrates was 21.68%. Another 17.34% Cu was further recovered from the flotation tailing by magnetic separation at 0.8 T. The cumulative recovery of copper reached 91.42%. The modifier LA played a positive role in facilitating the sulfidation of copper oxide with Na2S, and the combined collector COC was better than other collectors for the copper flotation. This technology has been successfully applied to industrial production, and the results are consistent with the laboratory data.

Preparation of graphite dispersed copper composite on copper plate with CO2 laser

Science.gov (United States)

Yokoyama, S.; Ishikawa, Y.; Muizz, M. N. A.; Hisyamudin, M. N. N.; Nishiyama, K.; Sasano, J.; Izaki, M.

2018-01-01

It was tried in this work to prepare the graphite dispersed copper composite locally on a copper plate with a CO2 laser. The objectives of this study were to clear whether copper graphite composite was prepared on a copper plate and how the composite was prepared. The carbon content at the laser spot decreased with the laser irradiation time. This mainly resulted from the elimination by the laser trapping. The carbon content at the outside of the laser spot increased with time. Both the laser ablation and the laser trapping did not act on the graphite particles at the outside of the laser spot. Because the copper at the outside of the laser spot melted by the heat conduction from the laser spot, the particles were fixed by the wetting. However, the graphite particles were half-floated on the copper plate. The Vickers hardness decreased with an increase with laser irradiation time because of annealing.

Modeling for copper transport within the boundary layer in an electrodialysis cell

International Nuclear Information System (INIS)

Ibanez, J. P.; Aracena, A.; Ipinza, J.; Cifuentes, L.

2004-01-01

A semi empirical model was developed to characterize the transport of cupric ions within the Nernst layer generated between electrolyte bulk and the membrane surface in an electrodialysis cell. The model was derived from fundamental equations and was reduced to a linear expression incorporating the cupric ion transport number in the Nernst layer (t+BL) and in the membrane (t+m). The model critical condition is t+BL <0.5 t+m. The model correctly fits the experimental data when t+BL is o.02. the model was validated with experimental results previously published by the authors and it accounts for a linear concentration gradient within the Nernst layer. (Author) 28 refs

Antimicrobial Properties of Copper Nanoparticles and Amino Acid Chelated Copper Nanoparticles Produced by Using a Soya Extract

Science.gov (United States)

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

The Hyrkkoelae native copper mineralization as a natural analogue for copper canisters

International Nuclear Information System (INIS)

Marcos, N.

1996-10-01

The Hyrkkoelae U-Cu mineralization is located in southwestern Finland, near the Palmottu analogue site. The age of the mineralization is estimated to be between 1.8 and 1.7 Ga. Petrological and mineralogical studies have demonstrated that this mineralization has many geological features that parallel those of the sites being considered for nuclear waste disposal in Finland. A particular feature is the existence of native copper and copper sulfides in open fractures in the near-surface zone. This allows us to study the native copper corrosion process in analogous conditions as expected to dominate in the nuclear fuel waste repository. The occurrence of uranyl compounds at these fractures permits also considerations about the sorption properties of the engineered barrier material (metallic copper) and its corrosion products. From the study of mineral assemblages or paragenesis, it appears that the formation of copper sulfide (djurleite, Cu 1.934 ) after native copper (Cu 0 ) under anoxic (reducing) conditions is enhanced by the availability of dissolved HS - in the groundwater circulating in open fractures in the near-surface zone. The minimum concentration of HS - in the groundwater is estimated to be of the order of 10 -5 M (∼ 10 -4 g/l) and the minimum pH value not lower than about 7.8 as indicated by the presence of calcite crystals in the same fracture. The present study is the first one that has been performed on findings of native copper in reducing, neutral to slightly alkaline groundwaters. Thus, the data obtained is of most relevance in improving models of anoxic corrosion of copper canisters. (orig.)

Thermal shock resistances of a bonding material of C/C composite and copper

International Nuclear Information System (INIS)

Kurumada, Akira; Oku, Tatsuo; Kawamata, Kiyohiro; Motojima, Osamu; Noda, Nobuaki; McEnaney, B.

1997-01-01

The purpose of this study is to contribute to the development and the safety design of plasma facing components for fusion reactor devices. We evaluated the thermal shock resistance and the thermal shock fracture toughness of a bonding material which was jointed a carbon-fiber-reinforced carbon composite (C/C composite) to oxygen-free copper. We also examined the microstructures of the bonding layers using a scanning electron microscope before and after thermal shock tests. The bonding material did not fracture during thermal shock tests. However, thermal cracks and delamination cracks were observed in the bonding layers. (author)

Electrically continuous graphene from single crystal copper verified by terahertz conductance spectroscopy and micro four-point probe

DEFF Research Database (Denmark)

Buron, Jonas Christian Due; Pizzocchero, Filippo; Jessen, Bjarke Sørensen

2014-01-01

The electrical performance of graphene synthesized by chemical vapor deposition and transferred to insulating surfaces may be compromised by extended defects, including for instance grain boundaries, cracks, wrinkles, and tears. In this study, we experimentally investigate and compare the nano......- and microscale electrical continuity of single layer graphene grown on centimeter-sized single crystal copper with that of previously studied graphene films, grown on commercially available copper foil, after transfer to SiO2 surfaces. The electrical continuity of the graphene films is analyzed using two...... for measurement of the complex conductance response in the frequency range 1-15 terahertz, covering the entire intraband conductance spectrum, and reveals that the conductance response for the graphene grown on single crystalline copper intimately follows the Drude model for a barrier-free conductor. In contrast...

Electrically continuous graphene from single crystal copper verified by terahertz conductance spectroscopy and micro four-point probe

DEFF Research Database (Denmark)

Buron, Jonas Christian Due; Pizzocchero, Filippo; Jessen, Bjarke Sørensen

2014-01-01

noninvasive conductance characterization methods: ultrabroadband terahertz time-domain spectroscopy and micro four-point probe, which probe the electrical properties of the graphene film on different length scales, 100 nm and 10 μm, respectively. Ultrabroadband terahertz time-domain spectroscopy allows......- and microscale electrical continuity of single layer graphene grown on centimeter-sized single crystal copper with that of previously studied graphene films, grown on commercially available copper foil, after transfer to SiO2 surfaces. The electrical continuity of the graphene films is analyzed using two....... Micro four-point probe resistance values measured on graphene grown on single crystalline copper in two different voltage-current configurations show close agreement with the expected distributions for a continuous 2D conductor, in contrast with previous observations on graphene grown on commercial...

Spectrographic determination of impurities in copper and copper oxide

International Nuclear Information System (INIS)

Sabato, S.F.; Lordello, A.R.

1990-11-01

An emission spectrographic method for the determination of Al, Bi, Ca, Cd, Cr, Fe, Ge, Mg, Mn, Mo, Ni, Pb, Sb, Si, Sn and Zn in copper and copper oxide is described. Two mixtures (Graphite and ZnO: graphite and GeO sub(2)) were used as buffers. The standard deviation lies around 10%. (author)

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

Directory of Open Access Journals (Sweden)

Rebeca Ortega-Amaya

2016-07-01

Full Text Available 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.

SU-F-I-06: Evaluation of Imaging Dose for Modulation Layer Based Dual Energy Cone-Beam CT

Energy Technology Data Exchange (ETDEWEB)

Ju, Eunbin [Department of Medical Science, Ewha Womans University, Seoul (Korea, Republic of); Ahn, SoHyun; Cho, Samju; Keum, Ki Chang [Department of Radiation Oncology, School of Medicine, Yonsei Univeristy, Seoul (Korea, Republic of); Lee, Rena [Department of Radiation Oncology, School of Medicine, Ewha Womans University, Seoul (Korea, Republic of)

2016-06-15

Purpose: Dual energy cone beam CT system is finding a variety of promising applications in diagnostic CT, both in imaging of endogenous materials and exogenous materials across a range of body sites. Dual energy cone beam CT system to suggest in this study acquire image by rotating 360 degree with half of the X-ray window covered using copper modulation layer. In the region that covered by modulation layer absorb the low energy X-ray by modulation layer. Relative high energy X-ray passes through the layer and contributes to image reconstruction. Dose evaluation should be carried out in order to utilize such an imaging acquirement technology for clinical use. Methods: For evaluating imaging dose of modulation layer based dual energy cone beam CT system, Prototype cone beam CT that configured X-ray tube (D054SB, Toshiba, Japan) and detector (PaxScan 2520V, Varian Medical Systems, Palo Alto, CA) is used. A range of 0.5–2.0 mm thickness of modulation layer is implemented in Monte Carlo simulation (MCNPX, ver. 2.6.0, Los Alamos National Laboratory, USA) with half of X-ray window covered. In-house phantom using in this study that has 3 cylindrical phantoms configured water, Teflon air with PMMA covered for verifying the comparability the various material in human body and is implemented in Monte Carlo simulation. The actual dose with 2.0 mm copper covered half of X-ray window is measured using Gafchromic EBT3 film with 5.0 mm bolus for compared with simulative dose. Results: Dose in phantom reduced 33% by copper modulation layer of 2.0 mm. Scattering dose occurred in modulation layer by Compton scattering effect is 0.04% of overall dose. Conclusion: Modulation layer of that based dual energy cone beam CT has not influence on unnecessary scatter dose. This study was supported by the Radiation Safety Research Programs (1305033) through the Nuclear Safety and Security Commission.

Improvement of copper plating adhesion on silane modified PET film by ultrasonic-assisted electroless deposition

International Nuclear Information System (INIS)

Lu Yinxiang

2010-01-01

Copper thin film on silane modified poly(ethylene terephthalate) (PET) substrate was fabricated by ultrasonic-assisted electroless deposition. The composition and topography of copper plating PET films were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and atomic force microscopy (AFM), respectively. Peel adhesion strength, as high as 16.7 N/cm, was achieved for the planting copper layer to the modified PET substrate with ultrasonic-assisted deposition; however, a relative low value as 11.9 N/cm was obtained for the sample without ultrasonic vibration by the same measurement. The electrical conductivity of Cu film was changed from 7.9 x 10 4 to 2.1 x 10 5 S/cm by using ultrasonic technique. Ultrasonic operation has the significant merits of fast deposition and formation of good membranes for electroless deposition of Cu on PET film.

Functional understanding of the versatile protein copper metabolism MURR1 domain 1 (COMMD1) in copper homeostasis

NARCIS (Netherlands)

Fedoseienko, Alina; Bartuzi, Paulina; van de Sluis, Bart

2014-01-01

Copper is an important cofactor in numerous biological processes in all living organisms. However, excessive copper can be extremely toxic, so it is vital that the copper level within a cell is tightly regulated. The damaging effect of copper is seen in several hereditary forms of copper toxicity in

Vapour galvanizing (Sherardizing) of copper with zinc

Energy Technology Data Exchange (ETDEWEB)

Wortelen, Dietbert; Bracht, Hartmut [Westfaelische Wilhelms-Universitaet Muenster (Germany); Natrup, Frank; Graf, Wolfram [Bodycote Waermebehandlung GmbH, Sprockhoevel (Germany)

2010-07-01

Using a vapour galvanizing technique called Sherardizing we investigated the growth kinetics and coefficients of zinc copper phases. For this purpose polished (OFHC)-copper plates and zinc powder have been sealed in quartz ampoules under inert gas atmospheres and annealed at a temperature range between 300 and 410 C. In order to study the coating thickness and the phase composition, cross sections were prepared, which have been analyzed by means of optical microscopy and scanning electron microscopy. We were able to demonstrate that the coating thickness is a function of the parabolic time law and that the formed coatings are composed of two layers referring to the ordered {beta}-CuZn and {gamma}-Cu{sub 5}Zn{sub 8}-phases. To enhance the coating quality, small amounts of ZnCl{sub 2} were added to the zinc powder. It was observed that the coating thickness decreased with increasing ZnCl{sub 2}. Experiments with variable Ar-pressure demonstrated a reduced coating growth with increasing pressures. Further measurements with ZnCl{sub 2} were performed to check whether an electrochemical mechanism is involved in the coating process.

Crystal structures of copper(II) chloride, copper(II) bromide, and copper(II) nitrate complexes with pyridine-2-carbaldehyde thiosemicarbazone

Science.gov (United States)

Chumakov, Yu. M.; Tsapkov, V. I.; Jeanneau, E.; Bairac, N. N.; Bocelli, G.; Poirier, D.; Roy, J.; Gulea, A. P.

2008-09-01

The crystal structures of chloro-(2-formylpyridinethiosemicarbazono)copper dimethyl sulfoxide solvate ( I), bromo-(2-formylpyridinethiosemicarbazono)copper ( II), and (2-formylpyridinethiosemicarbazono)copper(II) nitrate dimethyl sulfoxide solvate ( III) are determined using X-ray diffraction. In the crystals, complexes I and II form centrosymmetric dimers in which the thiosemicarbazone sulfur atom serves as a bridge and occupies the fifth coordination site of the copper atom of the neighboring complex related to the initial complex through the center of symmetry. In both cases, the coordination polyhedron of the complexing ion is a distorted tetragonal bipyramid. Complex III in the crystal structure forms polymer chains in which the copper atom of one complex forms the coordination bond with the thicarbamide nitrogen atom of the neighboring complex. In this structure, the coordination polyhedron of the central atom is an elongated tetragonal bipyramid. It is established that complexes I III at a concentration of 10-5 mol/l selectively inhibit the growth of 60 to 90 percent of the cancer tumor cells of the human myeloid leukemia (HL-60).

Crystal structures of copper(II) chloride, copper(II) bromide, and copper(II) nitrate complexes with pyridine-2-carbaldehyde thiosemicarbazone

International Nuclear Information System (INIS)

Chumakov, Yu. M.; Tsapkov, V. I.; Jeanneau, E.; Bairac, N. N.; Bocelli, G.; Poirier, D.; Roy, J.; Gulea, A. P.

2008-01-01

The crystal structures of chloro-(2-formylpyridinethiosemicarbazono)copper dimethyl sulfoxide solvate (I), bromo-(2-formylpyridinethiosemicarbazono)copper (II), and (2-formylpyridinethiosemicarbazono)copper(II) nitrate dimethyl sulfoxide solvate (III) are determined using X-ray diffraction. In the crystals, complexes I and II form centrosymmetric dimers in which the thiosemicarbazone sulfur atom serves as a bridge and occupies the fifth coordination site of the copper atom of the neighboring complex related to the initial complex through the center of symmetry. In both cases, the coordination polyhedron of the complexing ion is a distorted tetragonal bipyramid. Complex III in the crystal structure forms polymer chains in which the copper atom of one complex forms the coordination bond with the thicarbamide nitrogen atom of the neighboring complex. In this structure, the coordination polyhedron of the central atom is an elongated tetragonal bipyramid. It is established that complexes I-III at a concentration of 10 -5 mol/l selectively inhibit the growth of 60 to 90 percent of the cancer tumor cells of the human myeloid leukemia (HL-60).

Crystal structures of copper(II) chloride, copper(II) bromide, and copper(II) nitrate complexes with pyridine-2-carbaldehyde thiosemicarbazone

Energy Technology Data Exchange (ETDEWEB)

Chumakov, Yu. M., E-mail: chumakov.xray@phys.asm.md [Academy of Sciences of Moldova, Institute of Applied Physics (Moldova, Republic of); Tsapkov, V. I. [State University of Moldova (Moldova, Republic of); Jeanneau, E. [Universite Claude Bernard, Laboratoire des Multimateriaux et Interfaces (France); Bairac, N. N. [State University of Moldova (Moldova, Republic of); Bocelli, G. [National Research Council (IMEM-CNR), Institute of Materials for Electronics and Magnetism (Italy); Poirier, D.; Roy, J. [Centre Hospitalier Universitaire de Quebec (CHUQ) (Canada); Gulea, A. P. [State University of Moldova (Moldova, Republic of)

2008-09-15

The crystal structures of chloro-(2-formylpyridinethiosemicarbazono)copper dimethyl sulfoxide solvate (I), bromo-(2-formylpyridinethiosemicarbazono)copper (II), and (2-formylpyridinethiosemicarbazono)copper(II) nitrate dimethyl sulfoxide solvate (III) are determined using X-ray diffraction. In the crystals, complexes I and II form centrosymmetric dimers in which the thiosemicarbazone sulfur atom serves as a bridge and occupies the fifth coordination site of the copper atom of the neighboring complex related to the initial complex through the center of symmetry. In both cases, the coordination polyhedron of the complexing ion is a distorted tetragonal bipyramid. Complex III in the crystal structure forms polymer chains in which the copper atom of one complex forms the coordination bond with the thicarbamide nitrogen atom of the neighboring complex. In this structure, the coordination polyhedron of the central atom is an elongated tetragonal bipyramid. It is established that complexes I-III at a concentration of 10{sup -5} mol/l selectively inhibit the growth of 60 to 90 percent of the cancer tumor cells of the human myeloid leukemia (HL-60).

Experimental investigation of copper matrix longitudinal resistance in a composite Nb-Ti wire

International Nuclear Information System (INIS)

Gubkin, I.N.; Kozlenkova, N.I.; Nikulin, A.D.; Polikarpova, M.V.; Filkin, V.Ya.

1994-01-01

The longitudinal resistance of multifilamentary superconducting wires is among the major parameters used in design and optimization of superconducting magnetic systems. To enhance the conductivity of the copper matrix, it is made of pipes and rods of enhanced quality copper produced by electron beam melting (resistance ratio between two temperatures, 295 K and 4.2 K, R 295 /R 4.2 > 200). Yet for readily obtainable conductors this parameter is much lower. The reduction of the copper-matrix electrical conductivity may be attributed to wire-production technology involving processes such as extrusion, drawing and intermediate thermal processing, as well as to the size effect. Copper-matrix longitudinal resistance was studied as a function of wire diameter on specimens of multifilamentary Nb-Ti wire with filaments coated by a Nb layer. Experimental results are compared with the Sondheimer calculations for a monofilament conductor as well as with the Gavalloni calculations for an ideal wire with hexagonally located filaments. It has been shown that the best fit with the experiment is provided by the Sondheimer approximation. Comparison of the results of this work with other authors' data obtained for the specimens with no niobium barrier, allows the authors to single out the influence of a pure size effect and diffusion of Ti on the resistivity

High quality graphene synthesized by atmospheric pressure CVD on copper foil

OpenAIRE

Trinsoutrot, Pierre; Rabot, Caroline; Vergnes, Hugues; Delamoreanu, Alexandru; Zenasni, Aziz; Caussat, Brigitte

2013-01-01

International audience; Graphene was synthesized at 1000 °C by Atmospheric Pressure Chemical Vapor Deposition on copper foil from methane diluted in argon and hydrogen. The influence of the main synthesis parameters was studied on 2 × 2 cm2 foils in order to obtain continuous monolayer graphenewithout crystalline defect. The uniformity, crystal quality and number of layers of graphenewere analyzed by Raman spectroscopy and Scanning Electronic Microscopy. First, an increase of the annealing pr...

Copper(I) Thiocyanate (CuSCN) Hole-Transport Layers Processed from Aqueous Precursor Solutions and Their Application in Thin-Film Transistors and Highly Efficient Organic and Organometal Halide Perovskite Solar Cells

KAUST Repository

Wijeyasinghe, Nilushi

2017-07-28

This study reports the development of copper(I) thiocyanate (CuSCN) hole-transport layers (HTLs) processed from aqueous ammonia as a novel alternative to conventional n-alkyl sulfide solvents. Wide bandgap (3.4–3.9 eV) and ultrathin (3–5 nm) layers of CuSCN are formed when the aqueous CuSCN–ammine complex solution is spin-cast in air and annealed at 100 °C. X-ray photoelectron spectroscopy confirms the high compositional purity of the formed CuSCN layers, while the high-resolution valence band spectra agree with first-principles calculations. Study of the hole-transport properties using field-effect transistor measurements reveals that the aqueous-processed CuSCN layers exhibit a fivefold higher hole mobility than films processed from diethyl sulfide solutions with the maximum values approaching 0.1 cm2 V−1 s−1. A further interesting characteristic is the low surface roughness of the resulting CuSCN layers, which in the case of solar cells helps to planarize the indium tin oxide anode. Organic bulk heterojunction and planar organometal halide perovskite solar cells based on aqueous-processed CuSCN HTLs yield power conversion efficiency of 10.7% and 17.5%, respectively. Importantly, aqueous-processed CuSCN-based cells consistently outperform devices based on poly(3,4-ethylenedioxythiophene) polystyrene sulfonate HTLs. This is the first report on CuSCN films and devices processed via an aqueous-based synthetic route that is compatible with high-throughput manufacturing and paves the way for further developments.

The impact of hydrogen and oxidizing impurities in chemical vapor deposition of graphene on copper

Science.gov (United States)

Choubak, Saman

Graphene, the single-atom layer of carbon, has attracted scientists and technologists due to its outstanding physical and opto/electronic properties. The use of graphene in practical applications requires a reliable and cost-effective method to produce large area graphene films with low defects and controlled thicknesses. Direct growth of graphene using chemical vapor deposition (CVD) on copper, in which carbonaceous gaseous species react with the metal substrate in the presence of hydrogen at high temperatures (850-1100° C), led to high coverage of high quality graphene, opening up a promising future for methods of this type and a large step towards commercial realization of graphene products. The present thesis deals with the synthesis of graphene via low pressure CVD (LP-CVD) on copper catalyst using methane as the carbon precursor. The focus is mainly on the determination of the role of hydrogen and oxidizing impurities during graphene formation with an ultimate purpose: to elucidate a viable and reproducible method for the production of high quality graphene films compatible with industrial manufacturing processes. The role of molecular hydrogen in graphene CVD is explored in the first part of the thesis. Few studies claimed that molecular hydrogen etches graphene films on copper by conducting annealing experiments. On the other hand, we speculated that this graphene etching reaction is due to the presence of trace amount of oxygen in the furnace atmosphere. Thus, we took another approach and designed systematic annealing experiments to investigate the role of hydrogen in the etching reaction of graphene on copper foils. No evidence of graphene etching on copper was observed when purified ultra high purity (UHP) hydrogen was used at 825 °C and 500 mTorr. Nevertheless, graphene films exposed to the unpurified UHP hydrogen were etched due to the presence of oxidizing impurities. Our results show that hydrogen is not responsible for graphene etching reaction

Copper atomic-scale transistors.

Science.gov (United States)

Xie, Fangqing; Kavalenka, Maryna N; Röger, Moritz; Albrecht, Daniel; Hölscher, Hendrik; Leuthold, Jürgen; Schimmel, Thomas

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 (CuSO 4 + H 2 SO 4 ) 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 1 G 0 ( G 0 = 2e 2 /h; with e being the electron charge, and h being Planck's constant) or 2 G 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.

Physical state of implanted W in copper

International Nuclear Information System (INIS)

Borders, J.A.; Cullis, A.G.; Poate, J.M.

1975-01-01

Transmission electron microscopy and 4 He ion channeling measurements were combined to investigate the physical state of implanted W in copper. For 60 0 K implantations of 2 x 10 15 W cm -2 , W is found to be 100 percent substitutional and is still 90 percent substitutional for a dose of 10 16 W cm -2 . Implantation of 10 17 W cm -2 produces a thin disordered surface layer of W and Cu with the W occupying no regular lattice site. On annealing to 600 0 C, W precipitates are formed with dimensions of a few hundred A and certain preferred orientations in the Cu lattice. (auth)

Carbon-carbon composite and copper-composite bond damages for high flux component controlled fusion