WorldWideScience

Sample records for tetraruthenated copper porphyrazine

  1. Electrocatalytic reduction of nitrite on tetraruthenated metalloporphyrins/Nafion glassy carbon modified electrode

    Energy Technology Data Exchange (ETDEWEB)

    Calfuman, Karla [Facultad de Ciencias, Departamento de Quimica, Universidad de Chile, Las Palmeras 3425, Casilla 653, Nunoa, Santiago (Chile); Aguirre, Maria Jesus [Facultad de Quimica y Biologia, Departamento de Quimica de los Materiales, Universidad de Santiago de Chile, Santiago (Chile); Canete-Rosales, Paulina; Bollo, Soledad [Facultad de Ciencias Quimicas y Farmaceuticas, Departamento de Quimica Farmacologica y Toxicologica, Universidad de Chile, Santiago (Chile); Llusar, Rosa [Departamento de Quimica Fisica y Analitica, Universidad de Jaume I, Castellon (Spain); Isaacs, Mauricio, E-mail: misaacs@uchile.cl [Facultad de Ciencias, Departamento de Quimica, Universidad de Chile, Las Palmeras 3425, Casilla 653, Nunoa, Santiago (Chile)

    2011-10-01

    Highlights: > Preparation and characterization of modified electrodes with M(II) Tetraruthenated porphyrins onto a Nafion film. > The electrodes were characterized by SEM, TEM, AFM and SECM techniques. > The modified electrodes are active in the electrochemical reduction of nitrite at -660 mV vs Ag/AgCl. > GC/Nf/CoTRP modified electrode is more electrochemically active than their Ni and Zn analogues. - Abstract: This paper describes the electrochemical reduction of nitrite ion in neutral aqueous solution mediated by tetraruthenated metalloporphyrins (Co(II), Ni(II) and Zn(II)) electrostatically assembled onto a Nafion film previously adsorbed on glassy carbon or ITO electrodes. Scanning electron microscope (SEM-EDX) and transmission electron microscopy (TEM) results have shown that on ITO electrodes the macrocycles forms multiple layers with a disordered stacking orientation over the Nafion film occupying hydrophobic and hydrophilic sites in the polyelectrolyte. Atomic force microscopy (AFM) results demonstrated that the Nafion film is 35 nm thick and tetraruthenated metalloporphyrins layers 190 nm thick presenting a thin but compacted morphology. Scanning electrochemical microscopy (SECM) images shows that the Co(II) tetraruthenated porphyrins/Nf/GC modified electrode is more electrochemically active than their Ni and Zn analogues. These modified electrodes are able to reduce nitrite at -660 mV showing enhanced reduction current and a decrease in the required overpotential compared to bare glassy carbon electrode. Controlled potential electrolysis experiments verify the production of ammonia, hydrazine and hydroxylamine at potentials where reduction of solvent is plausible demonstrating some selectivity toward the nitrite ion. Rotating disc electrode voltammetry shows that the factor that governs the kinetics of nitrite reduction is the charge propagation in the film.

  2. Potential aluminium(III)- and gallium(III)-selective optical sensors based on porphyrazines.

    Science.gov (United States)

    Goslinski, Tomasz; Tykarska, Ewa; Kryjewski, Michal; Osmalek, Tomasz; Sobiak, Stanislaw; Gdaniec, Maria; Dutkiewicz, Zbigniew; Mielcarek, Jadwiga

    2011-01-01

    Porphyrazines possessing non-coordinating alkyl (propyl) and aralkyl (4-tert-butylphenyl) groups in the periphery were studied as optical sensors for a set of mono-, di- and trivalent cations. Investigated porphyrazines in the UV-Vis monitored titrations revealed significant responses towards aluminium and gallium cations, unlike other metal ions studied. Additionally, porphyrazine possessing 4-tert-butylphenyl peripheral substituents showed sensor property towards ruthenium cation and was chosen for further investigation. The presence of isosbestic points in absorption spectra for its titration with aluminium, gallium and ruthenium cations, accompanied by a linear Benesi-Hildebrand plot, proved complex formation. The continuous variation method was used to determine binding stoichiometry in 1:1 porphyrazine-metal ratio. X-Ray studies and density functional theory calculations were employed to investigate octa(4-tert-butylphenyl)porphyrazine structure. The results helped to explain the observed selectivity towards certain ions. Interaction between ion and porphyrazine meso nitrogen in a Lewis acid-Lewis base manner is proposed.

  3. Antibacterial effect of cationic porphyrazines and anionic phthalocyanine and their interaction with plasmid DNA

    Science.gov (United States)

    Hassani, Leila; Hakimian, Fatemeh; Safaei, Elham; Fazeli, Zahra

    2013-11-01

    Resistance to antibiotics is a public health issue and identification of new antibacterial agents is one of the most important goals of pharmacological research. Among the novel developed antibacterial agents, porphyrin complexes and their derivatives are ideal candidates for use in medical applications. Phthalocyanines differ from porphyrins by having nitrogen atoms link the individual pyrrol units. The aza analogues of the phthalocyanines (azaPcs) such as tetramethylmetalloporphyrazines are heterocyclic Pc analogues. In this investigation, interaction of an anionic phthalocyanine (Cu(PcTs)) and two cationic tetrapyridinoporphyrazines including [Cu(2,3-tmtppa)]4+ and [Cu(3,4-tmtppa)]4+ complexes with plasmid DNA was studied using spectroscopic and gel electrophoresis methods. In addition, antibacterial effect of the complexes against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria was investigated using dilution test method. The results indicated that both porphyrazines have significant antibacterial properties, but Cu(PcTs) has weak antibacterial effect. Compairing the binding of the phthalocyanine and the porphyrazines to DNA demonstrated that the interaction of cationic porphyrazines is stronger than the anionic phthalocyanine remarkably. The extent of hypochromicity and red shift of absorption spectra indicated preferential intercalation of the two porphyrazine into the base pairs of DNA helix. Gel electrophoresis result implied Cu(2,3-tmtppa) and Cu(3,4-tmtppa) are able to perform cleavage of the plasmid DNA. Consequently, DNA binding and cleavage might be one of the antibacterial mechanisms of the complexes.

  4. A complementary organic inverter of porphyrazine thin films: low-voltage operation using ionic liquid gate dielectrics.

    Science.gov (United States)

    Fujimoto, Takuya; Miyoshi, Yasuhito; Matsushita, Michio M; Awaga, Kunio

    2011-05-28

    We studied a complementary organic inverter consisting of a p-type semiconductor, metal-free phthalocyanine (H(2)Pc), and an n-type semiconductor, tetrakis(thiadiazole)porphyrazine (H(2)TTDPz), operated through the ionic-liquid gate dielectrics of N,N-diethyl-N-methyl(2-methoxyethyl)ammonium bis(trifluoromethylsulfonyl)imide (DEME-TFSI). This organic inverter exhibits high performance with a very low operation voltage below 1.0 V and a dynamic response up to 20 Hz. © The Royal Society of Chemistry 2011

  5. Copper transport.

    Science.gov (United States)

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

    1998-05-01

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

  6. Copper hypersensitivity

    DEFF Research Database (Denmark)

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

    2014-01-01

    . As a metal, it possesses many of the same qualities as nickel, which is a known strong sensitizer. Cumulative data on subjects with presumed related symptoms and/or suspected exposure showed that a weighted average of 3.8% had a positive patch test reaction to copper. We conclude that copper is a very weak...... 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...

  7. Copper (II)

    African Journals Online (AJOL)

    CLEMENT O BEWAJI

    ABSTRACT: A Schiff base was prepared from the reaction of 2 - amino - 3 – methylbutanoic acid and 2, 4 - pentanedione. The reaction of the prepared Schiff base with ethanolic solution of copper (II) chloride formed diaquo bis( N – 2 – amino – 3 - methylbutyl - 2, 4 - pentanedionato) copper (II) complex. The Schiff base is ...

  8. Electropolymerized supramolecular tetraruthenated porphyrins applied as a voltammetric sensor

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Monize M. da; Ribeiro, Gabriel H.; Faria, Anizio M. de; Bogado, Andre L.; Dinelli, Luis R., E-mail: dinelli@pontal.ufu.br [Universidade Federal de Uberlandia (UFU), Ituiutaba, MG (Brazil). Faculdade de Ciencias Integradas do Pontal; Batista, Alzir A. [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil). Departamento de Quimica

    2013-11-15

    Porphyrin 5,10,15,20-Tetra(4-pyridyl)manganese(III), [Mn-TPyP(H{sub 2}O){sub 2}]PF{sub 6}, and electropolymerized supramolecular porphyrins (ESP), {l_brace}Mn-TPyP(H{sub 2}O){sub 2}[RuCl{sub 3}(dppb)]{sub 4}{r_brace}PF{sub 6} (dppb = 1,4-bis(diphenylphosphine)butane), were synthesized and characterized. A thin solid film of ESP was obtained on a glass carbon electrode surface by a cyclic voltammetry method. The peak current increased with the number of voltammetric cycles, which shows a typical behavior of the species being adsorbed on the surface of the electrode. Cyclic voltammetry was also employed for acetaminophen quantification using an ESP modified electrode. The modified electrode shows a linear relationship between the anodic peak current and the concentration of acetaminophen (in the rage 0.05 to 0.7 mmol L{sup -1}. The performance of the modified electrode was verified by the determination of acetaminophen in a commercial pharmaceutical product and the results were in good agreement with those obtained by a control HPLC method. (author)

  9. 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

  10. Copper in plants

    OpenAIRE

    Yruela, Inmaculada

    2005-01-01

    Copper is an essential metal for normal plant growth and development, although it is also potentially toxic. Copper participates in numerous physiological processes and is an essential cofactor for many metalloproteins, however, problems arise when excess copper is present in cells. Excess copper inhibits plant growth and impairs important cellular processes (i.e., photosynthetic electron transport). Since copper is both an essential cofactor and a toxic element, involving a complex network o...

  11. Aquatic Life Criteria - Copper

    Science.gov (United States)

    Documents pertain to Aquatic Life Ambient Water Quality criteria for Copper (2007 Freshwater, 2016 Estuarine/marine). These documents contain the safe levels of Copper in water that should protect to the majority of species.

  12. 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....

  13. 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...

  14. Copper and silver halates

    CERN Document Server

    Woolley, EM; Salomon, M

    2013-01-01

    Copper and Silver Halates is the third in a series of four volumes on inorganic metal halates. This volume presents critical evaluations and compilations for halate solubilities of the Group II metals. The solubility data included in this volume are those for the five compounds, copper chlorate and iodate, and silver chlorate, bromate and iodate.

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

    Science.gov (United States)

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

  16. 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.

  17. Canine Copper-Associated Hepatitis

    NARCIS (Netherlands)

    Dirksen, Karen|info:eu-repo/dai/nl/412424428; Fieten, Hille|info:eu-repo/dai/nl/314112596

    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

  18. COPPER CABLE RECYCLING TECHNOLOGY

    International Nuclear Information System (INIS)

    Chelsea Hubbard

    2001-01-01

    The United States Department of Energy (DOE) continually seeks safer and more cost-effective technologies for use in deactivation and decommissioning (D and D) of nuclear facilities. The Deactivation and Decommissioning Focus Area (DDFA) of the DOE's Office of Science and Technology (OST) sponsors large-scale demonstration and deployment projects (LSDDPs). At these LSDDPs, developers and vendors of improved or innovative technologies showcase products that are potentially beneficial to the DOE's projects and to others in the D and D community. Benefits sought include decreased health and safety risks to personnel and the environment, increased productivity, and decreased costs of operation. The Idaho National Engineering and Environmental Laboratory (INEEL) generated a list of statements defining specific needs and problems where improved technology could be incorporated into ongoing D and D tasks. One such need is to reduce the volume of waste copper wire and cable generated by D and D. Deactivation and decommissioning activities of nuclear facilities generates hundreds of tons of contaminated copper cable, which are sent to radioactive waste disposal sites. The Copper Cable Recycling Technology separates the clean copper from contaminated insulation and dust materials in these cables. The recovered copper can then be reclaimed and, more importantly, landfill disposal volumes can be reduced. The existing baseline technology for disposing radioactively contaminated cables is to package the cables in wooden storage boxes and dispose of the cables in radioactive waste disposal sites. The Copper Cable Recycling Technology is applicable to facility decommissioning projects at many Department of Energy (DOE) nuclear facilities and commercial nuclear power plants undergoing decommissioning activities. The INEEL Copper Cable Recycling Technology Demonstration investigated the effectiveness and efficiency to recycle 13.5 tons of copper cable. To determine the effectiveness

  19. Copper resistance determinants in bacteria.

    Science.gov (United States)

    Brown, N L; Rouch, D A; Lee, B T

    1992-01-01

    Copper is an essential trace element that is utilized in a number of oxygenases and electron transport proteins, but it is also a highly toxic heavy metal, against which all organisms must protect themselves. Known bacterial determinants of copper resistance are plasmid-encoded. The mechanisms which confer resistance must be integrated with the normal metabolism of copper. Different bacteria have adopted diverse strategies for copper resistance, and this review outlines what is known about bacterial copper resistance mechanisms and their genetic regulation.

  20. Micromachining with copper lasers

    Science.gov (United States)

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

    1997-04-01

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

  1. Sliding Friction of Copper

    National Research Council Canada - National Science Library

    Liu, Tung

    1963-01-01

    .... With less clean surfaces, the coefficient of friction obtained was about 0.4. Since the degree of cleanliness cannot be controlled quantitatively, the friction - load curve of sliding copper pairs in air exhibits a bifurcation characteristic...

  2. LEP copper accelerating cavities

    CERN Multimedia

    Laurent Guiraud

    1999-01-01

    These copper cavities were used to generate the radio frequency electric field that was used to accelerate electrons and positrons around the 27-km Large Electron-Positron (LEP) collider at CERN, which ran from 1989 to 2000. The copper cavities were gradually replaced from 1996 with new superconducting cavities allowing the collision energy to rise from 90 GeV to 200 GeV by mid-1999.

  3. 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...

  4. 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.

  5. 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 ...

  6. Brazing copper to dispersion-strengthened copper

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-08-01

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

  7. Coping with copper

    DEFF Research Database (Denmark)

    Nunes, Ines Marques; Jacquiod, Samuel Jehan Auguste; Brejnrod, Asker Daniel

    2016-01-01

    Copper has been intensively used in industry and agriculture since mid-18(th) century and is currently accumulating in soils. We investigated the diversity of potential active bacteria by 16S rRNA gene transcript amplicon sequencing in a temperate grassland soil subjected to century-long exposure...

  8. and copper(II)

    Indian Academy of Sciences (India)

    Unknown

    characterization of several imidazolate-bridged binuclear copper(II) complexes have been reported 1–17. ... of the desired complex formed were collected, washed with ethanol and dried in vacuo at room temperature. .... 16. Sigel H (ed.) 1981 Metal ions in biological system (New York: Marcel Dekker) vol 13, p. 259. 17.

  9. Presenilin promotes dietary copper uptake.

    Directory of Open Access Journals (Sweden)

    Adam Southon

    Full Text Available Dietary copper is essential for multicellular organisms. Copper is redox active and required as a cofactor for enzymes such as the antioxidant Superoxide Dismutase 1 (SOD1. Copper dyshomeostasis has been implicated in Alzheimer's disease. Mutations in the presenilin genes encoding PS1 and PS2 are major causes of early-onset familial Alzheimer's disease. PS1 and PS2 are required for efficient copper uptake in mammalian systems. Here we demonstrate a conserved role for presenilin in dietary copper uptake in the fly Drosophila melanogaster. Ubiquitous RNA interference-mediated knockdown of the single Drosophila presenilin (PSN gene is lethal. However, PSN knockdown in the midgut produces viable flies. These flies have reduced copper levels and are more tolerant to excess dietary copper. Expression of a copper-responsive EYFP construct was also lower in the midgut of these larvae, indicative of reduced dietary copper uptake. SOD activity was reduced by midgut PSN knockdown, and these flies were sensitive to the superoxide-inducing chemical paraquat. These data support presenilin being needed for dietary copper uptake in the gut and so impacting on SOD activity and tolerance to oxidative stress. These results are consistent with previous studies of mammalian presenilins, supporting a conserved role for these proteins in mediating copper uptake.

  10. Copper uptake across rainbow trout gills: mechanisms of apical entry

    DEFF Research Database (Denmark)

    Grosell, Martin Hautopp; Wood, C. M.

    2002-01-01

    Copper, Homeostasis, sodium uptake, copper/sodium interactions, gill, rainbow trout, Oncorhynchus mykiss......Copper, Homeostasis, sodium uptake, copper/sodium interactions, gill, rainbow trout, Oncorhynchus mykiss...

  11. Multilevel cycle of anthropogenic copper.

    Science.gov (United States)

    Graedel, T E; van Beers, D; Bertram, M; Fuse, K; Gordon, R B; Gritsinin, A; Kapur, A; Klee, R J; Lifset, R J; Memon, L; Rechberger, H; Spatari, S; Vexler, D

    2004-02-15

    A comprehensive contemporary cycle for stocks and flows of copper is characterized and presented, incorporating information on extraction, processing, fabrication and manufacturing, use, discard, recycling, final disposal, and dissipation. The analysis is performed on an annual basis, ca. 1994, at three discrete governmental unit levels--56 countries or country groups that together comprise essentially all global anthropogenic copper stocks and flows, nine world regions, and the planet as a whole. Cycles for all of these are presented and discussed, and a "best estimate" global copper cycle is constructed to resolve aggregation discrepancies. Among the most interesting results are (1) transformation rates and recycling rates in apparently similar national economies differ by factors of two or more (country level); (2) the discard flows that have the greatest potential for copper recycling are those with low magnitude flows but high copper concentrations--electronics, electrical equipment, and vehicles (regional level); (3) worldwide, about 53% of the copper that was discarded in various forms was recovered and reused or recycled (global level); (4) the highest rate of transfer of discarded copper to repositories is into landfills, but the annual amount of copper deposited in mine tailings is nearly as high (global level); and (5) nearly 30% of copper mining occurred merely to replace copper that was discarded. The results provide a framework for similar studies of other anthropogenic resource cycles as well as a basis for supplementary studies in resource stocks, industrial resource utilization, waste management, industrial economics, and environmental impacts.

  12. and copper(II)

    Indian Academy of Sciences (India)

    Unknown

    that the imidazolate-bridged complex is stable over the pH-range 7⋅15–10⋅0. .... copper(II) complex. The observed room temperature magnetic moments are around. 1⋅79 BM, in agreement with a one-spin (S = 1/2) system. 3.2 EPR studies .... (SK) thanks the Council of Scientific & Industrial Research, New Delhi for an.

  13. Copper Pyrimidine based MOFs

    Indian Academy of Sciences (India)

    Cl..Cu.. interactions but restricted ..Cu..N N..Cu interacations. Supramolecular isomers of Br and I are reported for the first time in this paper. [Cu2I(pdz)X2]. Figure S18. Self assembly of the simultaneous presence of tecton {Cu(sol)3X} and {Cu(pdz)(sol)2X} result in [Cu2I(pdz)X2]. 1. Table S3. Copper Pyrimidine based MOFs ...

  14. 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.)

  15. Jet-printed copper metallization

    Science.gov (United States)

    Hong, Cheong Min

    Macroelectronics is a technology for making electronic circuits over very large areas at low cost. Flat panel displays, sensor arrays, and thin film solar cells are examples of macroelectronics. Crucial to the success of this new technology is the development of inexpensive electronic processes, materials, and devices. Direct printing techniques, which eliminate processing steps and save device and process materials, are the key to high volume and high throughput manufacturing. Copper metallization has been receiving increasing attention in both microelectronics and macroelectronics. Copper has high conductivity, density, melting point, heat capacity, and thermal conductivity. However, copper is also hard to dry etch. For these reasons we have developed and demonstrated a directly printed copper source/drain metallization technique and applied it to the fabrication of hydrogenated amorphous silicon (a-Si:H) thin film transistors (TFTs). The maximum process temperature of 200°C is compatible with conventional active matrix liquid crystal display (AMLCD) technology. In this dissertation, we show the process of depositing copper films by jet printing. We discuss the preparation and the properties of the copper precursor material used in the jet printing. We survey the conversion process from copper precursor to copper under varying processing conditions. The resulting copper film is probed for its physical, electrical, and mechanical properties. To demonstrate the feasibility of the jet printing technique, we print copper source/drain contacts for a-Si:H TFTs. The photolithography-free TFT fabrication process uses the printed xerographic toner technique developed earlier in this laboratory. We show that functional TFTs can be made with printed copper source and drain contacts. The jet printing of copper contacts represents a further step toward an all-printed thin film transistor technology.

  16. 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.

  17. 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)

  18. Studies of copper transport in mammalian cells using copper radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Camakaris, J.; Voskoboinik, I.; Brooks, H.; Greenough, M. [University of Melbourne, Parkville, VIC (Australia). Department of Genetics; Smith, S. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia). Radiopharmaceuticals Division; Mercer, J. [Deakin University, Clayton, VIC (Australia). Centre of Cellular and Molecular Biology

    1998-12-31

    The trace element copper poses a major problem for all organisms. It is essential 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. Using the copper radioisotopes {sup 64}Cu (t1/2 = 12.8 hr) and {sup 67}Cu (t1/2 = 61 hr) we have developed a number of systems for studying copper transport in mammalian cells. These include investigation of copper uptake, copper efflux and ligand blot assays for Cu-binding proteins. Our studies have focused on Menkes disease which is an inherited and usually lethal copper deficiency disorder in humans. We have demonstrated that the Menkes protein is directly involved as a copper efflux pump in mammalian cells. Using cells overexpressing the Menkes protein we have provided the first biochemical evidence that this functions as a Cu translocating (across the membrane) P-type ATPase (Voskoboinik et al., FEBS Letters, in press). These studies were carried out using purified plasma membrane vesicles. We are now carrying out structure- function studies on this protein using targeted mutations and assaying using the radiocopper vesicle assay. Recently we have commenced studies on the role of amyloid precursor protein (APP) in copper transport and relationship of this to Alzheimers disease

  19. Copper (II) complexes with aroylhydrazones

    Indian Academy of Sciences (India)

    Copper(II) complexes with aroylhydrazones ... The coordination chemistry of copper(II) with tridentate aroylhydrazones is briefly discussed in this article. ... EPR spectroscopy and variable temperature magnetic susceptibility measurements have been used to reveal the nature of the coordination geometry and magnetic ...

  20. The Bauschinger Effect in Copper

    DEFF Research Database (Denmark)

    Pedersen, Ole Bøcker; Brown, L .M.; Stobbs, W. M.

    1981-01-01

    A study of the Bauschinger effect in pure copper shows that by comparison with dispersion hardened copper the effect is very small and independent of temperature. This suggests that the obstacles to flow are deformable. A simple composite model based on this principle accounts for the data semi...

  1. Copper: From neurotransmission to neuroproteostasis

    Directory of Open Access Journals (Sweden)

    Carlos M Opazo

    2014-07-01

    Full Text Available Copper is critical for the Central Nervous System (CNS development and function. In particular, different studies have shown the effect of copper at brain synapses, where it inhibits Long Term Potentation (LTP and receptor pharmacology. Paradoxically, according to recent studies copper is required for a normal LTP response. Copper is released at the synaptic cleft, where it blocks glutamate receptors, which explain its blocking effects on excitatory neurotransmission. Our results indicate that copper also enhances neurotransmission through the accumulation of PSD95 protein, which increase the levels of AMPA receptors located at the plasma membrane of the post-synaptic density. Thus, our findings represent a novel mechanism for the action of copper, which may have implications for the neurophysiology and neuropathology of the CNS. These data indicate that synaptic configuration is sensitive to transient changes in transition metal homeostasis. Our results suggest that copper increases GluA1 subunit levels of the AMPA receptor through the anchorage of AMPA receptors to the plasma membrane as a result of PSD-95 accumulation. Here, we will review the role of copper on neurotransmission of CNS neurons. In addition, we will discuss the potential mechanisms by which copper could modulate neuronal proteostasis (neuroproteostasis in the CNS with focus in the Ubiquitin Proteasome System, which is particularly relevant to neurological disorders such Alzheimer’s disease (AD where copper and protein dyshomeostasis may contribute to neurodegeneration. An understanding of these mechanisms may ultimately lead to the development of novel therapeutic approaches to control metal and synaptic alterations observed in AD patients.

  2. 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,

  3. Copper complexes as 'radiation recovery' agents

    International Nuclear Information System (INIS)

    Sorenson, J.R.J.

    1989-01-01

    Copper and its compounds have been used for their remedial effects since the beginning of recorded history. As early as 3000 BC the Egyptians used copper as an antiseptic for healing wounds and to sterilise drinking water; and later, ca 1550 BC, the Ebers Papyrus reports the use of copper acetate, copper sulphate and pulverised metallic copper for the treatment of eye infections. These historical uses of copper and its compounds are particularly interesting in the light of modern evidence concerning the use of certain copper complexes for the treatment of radiation sickness and more recently as an adjunct to radiotherapy for cancer patients. (author)

  4. NID Copper Sample Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kouzes, Richard T.; Zhu, Zihua

    2011-09-12

    The current focal point of the nuclear physics program at PNNL is the MAJORANA DEMONSTRATOR, and the follow-on Tonne-Scale experiment, a large array of ultra-low background high-purity germanium detectors, enriched in 76Ge, designed to search for zero-neutrino double-beta decay (0νββ). This experiment requires the use of germanium isotopically enriched in 76Ge. The MAJORANA DEMONSTRATOR is a DOE and NSF funded project with a major science impact. The DEMONSTRATOR will utilize 76Ge from Russia, but for the Tonne-Scale experiment it is hoped that an alternate technology, possibly one under development at Nonlinear Ion Dynamics (NID), will be a viable, US-based, lower-cost source of separated material. Samples of separated material from NID require analysis to determine the isotopic distribution and impurities. DOE is funding NID through an SBIR grant for development of their separation technology for application to the Tonne-Scale experiment. The Environmental Molecular Sciences facility (EMSL), a DOE user facility at PNNL, has the required mass spectroscopy instruments for making isotopic measurements that are essential to the quality assurance for the MAJORANA DEMONSTRATOR and for the development of the future separation technology required for the Tonne-Scale experiment. A sample of isotopically separated copper was provided by NID to PNNL in January 2011 for isotopic analysis as a test of the NID technology. The results of that analysis are reported here. A second sample of isotopically separated copper was provided by NID to PNNL in August 2011 for isotopic analysis as a test of the NID technology. The results of that analysis are also reported here.

  5. Gallium and copper radiopharmaceutical chemistry

    International Nuclear Information System (INIS)

    Green, M.A.

    1991-01-01

    Gallium and copper radionuclides have a long history of use in nuclear medicine. Table 1 presents the nuclear properties of several gallium and copper isotopes that either are used in the routine practice of clinical nuclear medicine or exhibit particular characteristics that might make them useful in diagnostic or therapeutic medicine. This paper will provide some historic perspective along with an overview of some current research directions in gallium and copper radiopharmaceutical chemistry. A more extensive review of gallium radiopharmaceutical chemistry has recently appeared and can be consulted for a more in-depth treatment of this topic

  6. Copper tailings in stucco mortars

    Directory of Open Access Journals (Sweden)

    Osvaldo Pavez

    Full Text Available Abstract This investigation addressed the evaluation of the use of copper tailings in the construction industry in order to reduce the impact on the environment. The evaluation was performed by a technical comparison between stucco mortars prepared with crushed conventional sand and with copper tailings sand. The best results were achieved with the stucco mortars containing tailings. The tailings presented a fine particles size distribution curve different from that suggested by the standard. The values of compressive strength, retentivity, and adherence in the stucco mortars prepared with copper tailings were much higher than those obtained with crushed sand. According to the results from this study, it can be concluded that the preparation of stucco mortars using copper tailings replacing conventional sand is a technically feasible alternative for the construction industry, presenting the benefit of mitigating the impact of disposal to the environment.

  7. Hereditary iron and copper deposition

    DEFF Research Database (Denmark)

    Aaseth, Jan; Flaten, Trond Peder; Andersen, Ole

    2007-01-01

    Hereditary deposition of iron (primary haemochromatosis) or copper (Wilson's disease) are autosomal recessive metabolic disease characterized by progressive liver pathology and subsequent involvement of various other organs. The prevalence of primary haemochromatosis is approximately 0.5%, about...

  8. Copper atomic-scale transistors

    Directory of Open Access Journals (Sweden)

    Fangqing Xie

    2017-03-01

    Full Text Available We investigated copper as a working material for metallic atomic-scale transistors and confirmed that copper atomic-scale transistors can be fabricated and operated electrochemically in a copper electrolyte (CuSO4 + H2SO4 in bi-distilled water under ambient conditions with three microelectrodes (source, drain and gate. The electrochemical switching-on potential of the atomic-scale transistor is below 350 mV, and the switching-off potential is between 0 and −170 mV. The switching-on current is above 1 μA, which is compatible with semiconductor transistor devices. Both sign and amplitude of the voltage applied across the source and drain electrodes (Ubias 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 1G0 (G0 = 2e2/h; with e being the electron charge, and h being Planck’s constant or 2G0 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.

  9. The copper deposits of Michigan

    Science.gov (United States)

    Butler, B.S.; Burbank, W.S.

    1929-01-01

    The copper district of Keweenaw Point, in the northern peninsula of Michigan, is the second largest producer of copper in the world.  The output of the district since 1845 has been more than 7,500,000,000 pounds and showed a rather steady and consistent increase from the beginning of production to the end of the World War in 1918, since which there has been a marked decrease.

  10. 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

  11. 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....

  12. 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

  13. NID Copper Sample Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kouzes, Richard T.; Zhu, Zihua

    2011-02-01

    The current focal point of the nuclear physics program at PNNL is the MAJORANA DEMONSTRATOR, and the follow-on Tonne-Scale experiment, a large array of ultra-low background high-purity germanium detectors, enriched in 76Ge, designed to search for zero-neutrino double-beta decay (0νββ). This experiment requires the use of germanium isotopically enriched in 76Ge. The DEMONSTRATOR will utilize 76Ge from Russia, but for the Tonne-Scale experiment it is hoped that an alternate technology under development at Nonlinear Ion Dynamics (NID) will be a viable, US-based, lower-cost source of separated material. Samples of separated material from NID require analysis to determine the isotopic distribution and impurities. The MAJORANA DEMONSTRATOR is a DOE and NSF funded project with a major science impact. DOE is funding NID through an SBIR grant for development of their separation technology for application to the Tonne-Scale experiment. The Environmental Molecular Sciences facility (EMSL), a DOE user facility at PNNL, has the required mass spectroscopy instruments for making these isotopic measurements that are essential to the quality assurance for the MAJORANA DEMONSTRATOR and for the development of the future separation technology required for the Tonne-Scale experiment. A sample of isotopically separated copper was provided by NID to PNNL for isotopic analysis as a test of the NID technology. The results of that analysis are reported here.

  14. 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.

  15. Copper metallurgy at the crossroads

    Directory of Open Access Journals (Sweden)

    Habashi F.

    2007-01-01

    Full Text Available Copper technology changed from the vertical to the horizontal furnace and from the roast reaction to converting towards the end of the last century. However, the horizontal furnace proved to be an inefficient and polluting reactor. As a result many attempts were made to replace it. In the past 50 years new successful melting processes were introduced on an industrial scale that were more energy efficient and less polluting. In addition, smelting and converting were conducted in a single reactor in which the concentrate was fed and the raw copper was produced. The standing problem in many countries, however, is marketing 3 tonnes of sulfuric acid per tonne of copper produced as well as emitting large amounts of excess SO2 in the atmosphere. Pressure hydrometallurgy offers the possibility of liberating the copper industry from SO2 problem. Heap leaching technology has become a gigantic operation. Combined with solvent extraction and electrowinning it contributes today to about 20% of copper production and is expected to grow. Pressure leaching offers the possibility of liberating the copper industry from SO2 problem. The technology is over hundred years old. It is applied for leaching a variety of ores and concentrates. Hydrothermal oxidation of sulfide concentrates has the enormous advantage of producing elemental sulfur, hence solving the SO2 and sulfuric acid problems found in smelters. Precipitation of metals such as nickel and cobalt under hydrothermal conditions has been used for over 50 years. It has the advantage of a compact plant but the disadvantage of producing ammonium sulfate as a co-product. In case of copper, however, precipitation takes place without the need of neutralizing the acid, which is a great advantage and could be an excellent substitute for electrowinning which is energy intensive and occupies extensive space. Recent advances in the engineering aspects of pressure equipment design open the door widely for increased

  16. 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

  17. Leaching of Copper Ore by Thiobacillus Ferrooxidans.

    Science.gov (United States)

    Lennox, John; Biaha, Thomas

    1991-01-01

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

  18. Electrochemical behaviour of alkaline copper complexes

    Indian Academy of Sciences (India)

    cyanide- plating bath for copper has been developed using alkaline trisodium citrate and triethanolamine solutions5. The present investigation presents cyclic voltammetric studies on the electrochemical behaviour of alkaline copper complexes, ...

  19. Testing Corrosion Inhibitors for the Conservation of Archaeological Copper and Copper Alloys

    Directory of Open Access Journals (Sweden)

    Robert B. Faltermeier

    1997-11-01

    Full Text Available This is a synopsis of the Ph.D. research undertaken at the Institute of Archaeology, University College London. The aim was to evaluate corrosion inhibitors for use in the conservation of copper and copper alloy archaeological artefacts. The objective of this work was to acquire an insight into the performance of copper corrosion inhibitors, when applied to archaeological copper.

  20. Copper tolerance of Trichoderma species

    Directory of Open Access Journals (Sweden)

    Jovičić-Petrović Jelena

    2014-01-01

    Full Text Available Some Trichoderma strains can persist in ecosystems with high concentrations of heavy metals. The aim of this research was to examine the variability of Trichoderma strains isolated from different ecosystems, based on their morphological properties and restriction analysis of ITS fragments. The fungal growth was tested on potato dextrose agar, amended with Cu(II concentrations ranging from 0.25 to 10 mmol/l, in order to identify copper-resistant strains. The results indicate that some isolated strains of Trichoderma sp. show tolerance to higher copper concentrations. Further research to examine the ability of copper bioaccumulation by tolerant Trichoderma strains is needed. [Projekat Ministarstva nauke Republike Srbije, br. TR 31080 i br. III 43010

  1. Mechanochemical reduction of copper sulfide

    DEFF Research Database (Denmark)

    Balaz, P.; Takacs, L.; Jiang, Jianzhong

    2002-01-01

    The mechanochemical reduction of copper sulfide with iron was induced in a Fritsch P-6 planetary mill, using WC vial filled with argon and WC balls. Samples milled for specific intervals were analyzed by XRD and Mossbauer spectroscopy. Most of the reaction takes place during the first 10 min...... of milling and only FeS and Cu are found after 60 min. The main chemical process is accompanied by phase transformations of the sulfide phases as a result of milling. Djurleite partially transformed to chalcocite and a tetragonal copper sulfide phase before reduction. The cubic modification of FeS was formed...... first, transforming to hexagonal during the later stages of the process. The formation of off-stoichiometric phases and the release of some elemental sulfur by copper sulfide are also probable....

  2. Laser sintering of copper nanoparticles

    International Nuclear Information System (INIS)

    Zenou, Michael; Saar, Amir; Ermak, Oleg; Kotler, Zvi

    2014-01-01

    Copper nanoparticle (NP) inks serve as an attractive potential replacement to silver NP inks in functional printing applications. However their tendency to rapidly oxidize has so far limited their wider use. In this work we have studied the conditions for laser sintering of Cu-NP inks in ambient conditions while avoiding oxidation. We have determined the regime for stable, low-resistivity copper (< ×3 bulk resistivity value) generation in terms of laser irradiance and exposure duration and have indicated the limits on fast processing. The role of pre-drying conditions on sintering outcome has also been studied. A method, based on spectral reflectivity measurements, was used for non-contact monitoring of the sintering process evolution. It also indicates preferred spectral regions for sintering. Finally, we illustrated how selective laser sintering can generate high-quality, fine line (<5 µm wide) and dense copper circuits. (paper)

  3. Refining processes in the copper casting technology

    OpenAIRE

    Rzadkosz, S.; Kranc, M.; Garbacz-Klempka, A.; Kozana, J.; Piękoś, M.

    2015-01-01

    The paper presents the analysis of technology of copper and alloyed copper destined for power engineering casts. The casts quality was assessed based on microstructure, chemical content analysis and strength properties tests. Characteristic deoxidising (Logas, Cup) and modifying (ODM2, Kupmod2) formulas were used for the copper where high electrical conductivity was required. Chosen examples of alloyed copper with varied Cr and Zr content were studied, and the optimal heat treatment parameter...

  4. Tunable synthesis of copper nanotubes

    International Nuclear Information System (INIS)

    Kaniukov, E; Yakimchuk, D; Kozlovsky, A; Shlimas, D; Zdorovets, M; Kadyrzhanov, K

    2016-01-01

    Simple method of tunable synthesis of copper nanotubes based on template synthesis was developed. A comprehensive study of the structural, morphological and electrical characteristics of the obtained nanostructures was carried out. Characterization of structural features was made by methods of scanning electron microscopy, energy dispersive spectroscopy and X-ray diffractometry analysis. Evaluation of wall thickness is made by methods of gas permeability. Electrical conductivity of nanotubes was define in the study of their current-voltage characteristics. The possibility to control of copper nanotubes physical properties by variation of the deposition parameters was shown. (paper)

  5. 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 ...

  6. Joining of alumina via copper/niobium/copper interlayers

    Energy Technology Data Exchange (ETDEWEB)

    Marks, Robert A.; Chapman, Daniel R.; Danielson, David T.; Glaeser, Andreas M.

    2000-03-15

    Alumina has been joined at 1150 degrees C and 1400 degrees C using multilayer copper/niobium/copper interlayers. Four-point bend strengths are sensitive to processing temperature, bonding pressure, and furnace environment (ambient oxygen partial pressure). Under optimum conditions, joints with reproducibly high room temperature strengths (approximately equal 240 plus/minus 20 MPa) can be produced; most failures occur within the ceramic. Joints made with sapphire show that during bonding an initially continuous copper film undergoes a morphological instability, resulting in the formation of isolated copper-rich droplets/particles at the sapphire/interlayer interface, and extensive regions of direct bonding between sapphire and niobium. For optimized alumina bonds, bend tests at 800 degrees C-1100 degrees C indicate significant strength is retained; even at the highest test temperature, ceramic failure is observed. Post-bonding anneals at 1000 degrees C in vacuum or in gettered argon were used to assess joint stability and to probe the effect of ambient oxygen partial pressure on joint characteristics. Annealing in vacuum for up to 200 h causes no significant decrease in room temperature bend strength or change in fracture path. With increasing anneal time in a lower oxygen partial pressure environment, the fracture strength decreases only slightly, but the fracture path shifts from the ceramic to the interface.

  7. Structure transitions between copper-sulphate and copper-chloride ...

    Indian Academy of Sciences (India)

    Administrator

    Abstract. Structure transitions between copper UPD adlayers on Au(111)–(1 × 1) in sulfuric acid and chloride containing electrolyte were investigated by in situ scanning tunnelling microscopy. We demon- strate that co-adsorbed sulphate ions in the (√3 × √3)R30° UPD adlayer are replaced by chloride ions and,.

  8. A copper vapor laser by using a copper-vapor-complex reaction at a low temperature

    OpenAIRE

    Kano, Toshiyuki; Taniguchi, Hiroshi; Saito, Hiroshi

    1987-01-01

    A copper vapor laser performance by using ametal-vapor-complex reaction (Cu+AlBr3) is reported. The laser operation is obtained at a low temperature without externalheating because of the AlBr3 vapors evaporating at a room temperature. The copper vapor laser using this metal-vapor-complex reaction has an advantage of deposition-free of a metallic copper to the laser tube wall, which is different from the copper halide and the organometallic copper lasers.

  9. on THICKNESS OF COPPER (|) OXIDE

    African Journals Online (AJOL)

    2006-12-20

    Dec 20, 2006 ... semiconductor devices. The oxide is. Observed to be an attractive starting material for the production of solar cells for low cost terrestrial conversion of solar energy to electricity. Copper (I) oxide is one Of the earliest known photovoltaic materials and the first in which the photovOltaic effect was successfully ...

  10. A Study of Protection of Copper Alloys

    International Nuclear Information System (INIS)

    Kim, E. A.; Kim, S. H.; Kim, C. R.

    1974-01-01

    Volatile treatment of high capacity boiler water with hydrazine and ammonia is studied. Ammonia comes from the decomposition of excess hydrazine injected to treat dissolved oxygen. Ammonia is also injected for the control of pH. To find an effect of such ammonia on the copper alloy, the relations between pH and iron, and ammonia and copper are studied. Since the dependence of corrosion of iron on pH differs from that of copper, a range of pH was selected experimentally to minimize the corrosion rates of both copper and iron. Corrosion rates of various copper alloys are also compared

  11. Chronic copper toxicity in a dairy herd

    OpenAIRE

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

    1990-01-01

    The addition of excessive copper to a commercially prepared dairy ration caused chronic copper toxicity in a dairy herd. A formulation error by a feed company resulted in copper levels of 800 to 1,000 mg/kg in the “as fed concentrate,” amounting to about 400-500 mg copper/kg of the whole ration. Five animals died with typical signs of acute copper toxicity, including intravascular hemolysis and methemoglobinemia. A further 39 cows died on the farm from a combination of debilitation and second...

  12. Controlling Copper Electrochemical Deposition (ECD)

    Science.gov (United States)

    West, Michael; McDonald, Robert; Anderson, Marc; Kingston, Skip; Mui, Rudy

    2003-09-01

    The implementation of copper processing in semiconductor manufacturing has resulted in major process development and manufacturing challenges. A fundamental understanding of the copper plating processes used in manufacturing has been limited by the lack of in-line methods for direct measurement and control of process chemistry. Plating bath chemistry adjustments and change-out frequencies are currently determined using a combination of indirect electrochemical monitoring techniques, off-line analyses of wafer metrology and analytical lab measurements. There have been a number of industry reports of major process startup delays, yield management problems and reliability issues as a result of these difficulties. A new in-process mass spectrometry (IPMS) approach enables automated, real-time measurement of both the inorganic components and organic additives in the copper electroplating chemistry as they change during production. The tool is not only capable of real time direct quantification of the copper, chloride, pH, and organic additives in the plating bath, but can also monitor additive breakdown byproducts as they occur during the production process. These breakdown products, as well as changes in the original bath constituent composition can be expected to have a major impact on process performance. We are now in the process of measuring longer term plating bath stability and chemistry changes in prototype applications in semiconductor fab manufacturing environments. The first results demonstrate improved process understanding and the potential for greatly improved process control. We will discuss the technical challenges that were successfully addressed in developing the IPMS capability for application to the copper plating process and the initial process data subsequently obtained.

  13. Serum copper and ceruloplasmin levels and urinary copper excretion in thermal injury.

    Science.gov (United States)

    Boosalis, M G; McCall, J T; Solem, L D; Ahrenholz, D H; McClain, C J

    1986-12-01

    Conflicting reports regarding copper status in thermal injury patients have been published. We determined serial serum-copper and serum-ceruloplasmin levels and 24-h urinary excretion of copper in 23 patients with second- and third-degree thermal burns. Throughout hospitalization, mean serum-copper concentration was significantly depressed; lowest levels were found in patients with greater than 40% total body surface area burns. Serum ceruloplasmin was also depressed, an unexpected finding because this protein is a positive acute-phase reactant poststress. Mean urinary excretion of copper was elevated, reaching 2.5 times the upper limit of normal 2 wk postburn. Depressed serum-copper levels paralleled the serum-ceruloplasmin levels rather than the increased urinary-copper losses. Further studies are required to determine the mechanism(s) of this altered copper metabolism and whether physiological or biochemical evidence of copper deficiency accompanies the observed hypocupremia.

  14. Variations of serum copper values in pregnancy

    Directory of Open Access Journals (Sweden)

    Vukelić Jelka

    2012-01-01

    Full Text Available Introduction. Copper is essential micronutrient and has an important role in the human body. The serum copper increases during pregnancy and is doubled at full term. Lower levels of serum copper in pregnancy are connected with some pathological conditions. Objective. The aim of this study was to estimate the levels of serum copper in normal and pathological pregnancies, comparing them with values of serum copper in non-pregnant women, to determine if serum copper is lower in some pathological pregnancies and if this is of some importance. Methods. A total of 2170 plasma samples for copper analyses were made in the following groups: healthy non-pregnant women; healthy pregnant women from the 5th-40th gestational week, during the first delivery stage and during the first three postpartum weeks, in pregnant women with habitual abortion, imminent abortion, abortion in progress, missed abortion (9th-24th weeks, missed labour and premature rupture of membranes (29th-40th weeks. Levels of serum copper were determined by colorimetric technique of bathocuproin with disulphate as a chromogen. Results. Serum copper values in non-pregnant women range from 11.6-25.8 μmol/L. In healthy pregnant women, there is a constant trend of the increase of serum copper. The mean serum copper values revealed three significant peaks at the 22nd, 27th and 35th gestational week. Serum copper values in the patients with some pathological pregnancies in relation to the serum copper values of the healthy pregnant women were significantly lower. Conclusion. Serum copper values can be used as an indicator of some pathological pregnancies.

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

    Directory of Open Access Journals (Sweden)

    Choveaux David L

    2012-11-01

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

  16. 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.

  17. 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...

  18. Ammonia leaching of copper smelter dust and precipitation as copper sulphide

    International Nuclear Information System (INIS)

    Morales, A.; Hevia, J. F.; Cifuentes, G.

    2009-01-01

    The effect of ammonia on the leaching of copper smelter dust and copper precipitation from these solutions as sulphide using sulfur and sulfur dioxide was studied. The precipitation was done in ammoniacal media because this solution produced more satisfactory results at room temperature that a sulphuric media. A solid was precipitated containing 60 % of copper of the dust smelter. The other waste generated contained around 80 % of the arsenic of the original copper smelter dust. Based on the preliminary results obtained in this work it will propose a procedure for the recovery of copper as sulphide from copper smelter dust with parallel confinement of arsenic. (Author) 14 refs.

  19. Canine Models for Copper Homeostasis Disorders

    Directory of Open Access Journals (Sweden)

    Xiaoyan Wu

    2016-02-01

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

  20. Thermal conductivity of glass copper-composite

    International Nuclear Information System (INIS)

    Kinoshita, Makoto; Terai, Ryohei; Haidai, Haruki

    1980-01-01

    Glass-metal composites are to be one of the answers for promoting thermal conduction in the glassy solids containing high-level radioactive wastes. In order to investigate the effect of metal addition on thermal conductivity of glasses, glass-copper composites were selected, and the conductivities of the composites were measured and discussed in regards to copper content and microstructure. Fully densified composites were successfully prepared by pressure sintering of the powder mixtures of glass and copper at temperatures above the yield points of the constituent glasses if the copper content was not so much. The conductivity was measured by means of a comparative method, in which the thermal gradient of the specimen was compared with that of quartz glass as standard under thermally steady state. Measurements were carried out at around 50 0 C. The thermal conductivity increased with increasing content of copper depending on the kind of copper powder used. The conductivities of the composites of the same copper content differed considerably each another. Fine copper powder was effective on increasing conductivity, and the conductivity became about threefold of that of glass by mixing the fine copper powder about 10 vol%. For the composites containing the fine copper powder less than 5 vol%, the conductivity obeyed so-called logarithmic rule, one of the mixture rules of conductivity, whereas for composites containing more than 5 vol%, the conductivity remarkably increased apart from the rule. This fact suggests that copper becomes continuous in the composite when the copper content increased beyond 5 vol%. For the composites containing coarse copper powder, the conductivity was increased not significantly, and obeyed an equation derived from the model in which conductive material dispersed in less conductive one. (author)

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

    Science.gov (United States)

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

    2011-01-01

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

  2. LEP Radio Frequency Copper Cavity

    CERN Multimedia

    The pulse of a particle accelerator. 128 of these radio frequency cavities were positioned around CERN's 27-kilometre LEP ring to accelerate electrons and positrons. The acceleration was produced by microwave electric oscillations at 352 MHz. The electrons and positrons were grouped into bunches, like beads on a string, and the copper sphere at the top stored the microwave energy between the passage of individual bunches. This made for valuable energy savings as it reduced the heat generated in the cavity.

  3. 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

  4. Electronics scrap processing at Brixlegg copper works

    Energy Technology Data Exchange (ETDEWEB)

    Kaltenboeck, F.J.; Sauer, E.; Woebking, H.; Woerz, H.

    1985-11-01

    The valuable metals - in particular precious metals, copper, zinc, and tin - that are included in electronics scraps are recovered in the secondary copper works of Brixlegg in the form of commercial intermediate products or in the form of pure metals. The refinery line is as follows: shaft furnace, converter, anode furnace, electrolytic copper refinery and slime plants for precious metal recovery from anode slimes. (orig.).

  5. Microstructure effects in CVD copper

    Science.gov (United States)

    Manger, Dirk Karl

    Computer chip manufacturers are beginning to implement copper as interconnect material in high-performance microprocessor metallization architectures. Replacing currently used aluminum metallization with its copper based counterpart will result in performance gain due to the low resistivity of copper (1.67muO·cm) which generates a reduction in (resistance x capacitance) signal delay. Futhermore, enhancements in stress and electromigration resistance by up to three orders of magnitude are expected from replacing aluminum with copper. Copper deposited by chemical vapor deposition has the proven ability to yield complete fill of aggressive via and trench structures at high deposition rates. At the same time, ultrathin Cu seed layers can be controlled grown by chemical vapor deposition (CVD) for use as activation layer in electrolytic plating (EP) applications. Additionally, integration studies using single and two-level damascene interconnect structures CVD Cu showed that excellent yield can be obtained. However, before CVD Cu can be incorporated into manufacturing process flows, several key reliability issues have to be addressed and resolved. At present, electroplating has the advantage of enhanced electromigration performance compared to CVD copper. It is therefore necessary to demonstrate the systematic ability to tailor the microstructure of CVD copper with the goal of enhanced electromigration and stress migration performance through the successful formation of (111) textured Cu with bamboo type microstructure. In the present work, the evolution of as-deposited Cu resistivity, grain size, texture, and surface roughness were systematically analyzed as a function of film thickness for an optimized CVD Cu process. In particular, investigations of the influence of substrate type and surface pretreatment on texture and grain size showed that: (a) Cu grows (111) textured on PVD TiN, if (002) Ti matrix is present, and on inorganic CVD TiN, regardless of the underlying

  6. Copper welding; Les liaisons du cuivre

    Energy Technology Data Exchange (ETDEWEB)

    Monneau, Ph. [SDMS, 38 - Saint-Romans (France)

    2000-07-01

    The following categories of manufactured copper: Cu-c ( > 99.95% copper and less than 0.0003% phosphor) and Cu-OF (oxygen free copper) are useful in vacuum or ultra-vacuum techniques. Homogeneous binding (or heterogeneous with other metals) are mainly performed by welding (TIG, MIG, FE) or by brazing at high or low temperatures. In this article these different methods are reviewed with pros and cons, and several applications are presented, particularly the designing of high frequency resonator cavities for GANIL accelerator, these cavities were made out of solid copper. (A.C.)

  7. 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...

  8. Performance characteristics, plasma lipids and copper residue in ...

    African Journals Online (AJOL)

    Copper proteinate) and inorganic (Copper sulphate) Cu source on growth performance, plasma lipids and copper residue in organs and tissues of cockerel chickens. 240 day-old commercial Black-Harco cockerel chicks were randomly distributed to ...

  9. Copper Electroforming at the Canfranc Underground Laboratory. Status Report

    International Nuclear Information System (INIS)

    Borjabad, S.; Amare, J.; Morales, J.; Ortiz de Solorzano, A.; Villar, J. A.

    2007-01-01

    A brief summary of the copper electroforming process is given. The process parameters tuning to attain a copper part with the required characteristics is explained. Several electroformed copper parts with complicated geometry are described. Some radiopurity measurements are provided

  10. 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/.

  11. 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/

  12. Energy and materials flows in the copper industry

    Energy Technology Data Exchange (ETDEWEB)

    Gaines, L.L.

    1980-12-01

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

  13. Copper-complexing ligands produced by an intact estuarine microbial community in response to copper stress.

    Science.gov (United States)

    Bingham, J.; Dryden, C.; Gordon, A.

    2002-12-01

    Copper is both an important nutrient and a pollutant in the marine environment. By studying the interactions between microorganisms and copper in the Elizabeth River (VA), home to a major Naval Base, we field tested the hypothesis that picoplankton and/or bacterioplankton produce strong, copper-complexing ligands in response to elevated copper concentrations. A simple light/ dark test was used to distinguish between heterotrophic and phototrophic ligand production. Samples were bottled and moored, submerged one meter, for a week. Direct counts using DAPI stain and epiflourescence were conducted to find concentrations of picoplankton and bacterioplankton. Using cathodic stripping voltammetry, we found the total copper concentrations, and then from a titration of the ligands by copper, the ligand concentrations and conditional stability constants were obtained. The Elizabeth River naturally had between 10-20 nM total dissolved copper concentrations. However when copper complexation was considered we found that the levels of bio-available Cu(II) ions were much lower. In fact in the natural samples the levels were not high enough to affect the relative reproductive rates of several microorganisms. Naturally there was a 50 nM "buffer zone" of ligand to total dissolved copper concentration. Furthermore, when stressed with excess copper, healthy picoplankton produced enough ligand to alleviate toxicity, and rebuild the buffer zone. However bacterioplankton only produced enough ligand so that they were no longer affected. Therefore, intact estuarine communities regulate copper bioavailability and toxicity with ligand production.

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Plasma Copper Status in Hypercholesterolemic Patients

    African Journals Online (AJOL)

    Dr Femi Olaleye

    ... Rosenstein, F., and Lei, K.Y.. (1994): Pool size and concentration of plasma cholesterol are increased and tissue copper levels are reduced during early stages of copper deficiency in rats. J. Nutr. 124, 628-635. Anon (2000): Cardiovascular disease ranks as the first cause of death in Spain. Rev Esp Salud Publica 74 (3),.

  16. Extra-Hepatic Storage of Copper

    DEFF Research Database (Denmark)

    Heydorn, Kaj; Damsgaard, Else; Horn, N.

    1975-01-01

    The distribution of copper among the organs of an aborted, male foetus, expected to develop Menkes' syndrome, was entirely different from the distribution in 4 normal foetuses. Copper concentrations determined by neutron activation analysis showed a considerably reduced content in the liver, but ...

  17. Material characterization of ancient Indian copper

    Indian Academy of Sciences (India)

    Keywords. Ancient Indian copper; material characterization; electrochemical behaviour; rust analysis; corrosion rate. Abstract. A chalcolithic (2350–1800 BC) copper chisel from Balathal has been characterized by X-ray diffraction, microstructural and electrochemical methods. The surface patina was composed of sulfates ...

  18. Pharmacological Properties of Nanometals (Silver, Copper, Iron)

    OpenAIRE

    Chekman, I.S.

    2015-01-01

    The article summarizes the results of studies on the pharmacological, toxicological and specific properties of nanometals (silver, iron, copper). It is established that nanoparticles of silver, copper, iron exhibit antimicrobial action. Acute toxicity of nanometals depends on their nature, administration route and animal sex. Effects on heart activity and hemodynamic status as well as erythrocyte osmotic fragility have dose-dependent nature.

  19. Chemistry of the copper silicon interface

    International Nuclear Information System (INIS)

    Ford, M.J.; Sashin, V.A.; Nixon, K.

    2002-01-01

    Full text: Copper and silicon readily interdiffuse, even at room temperature, to form an interface which can be several nanometers thick. Over the years considerable effort has gone into investigating the diffusion process and chemical nature of the interface formed. Photoemission measurements give evidence for the formation of a stable suicide with a definite stoichiometry, Cu 3 Si. This is evidenced by splitting of the Si LVV Auger line and slight shifts and change in shape of the copper valence band density of states as measured by ultra-violet photoemission. In this paper we present calculations of the electronic structure of copper suicide, bulk copper and silicon, and preliminary measurements of the interface by electron momentum spectroscopy. Densities of states for copper and copper suicide are dominated by the copper 3d bands, and difference between the two compounds are relatively small. By contrast, the full band structures are quite distinct. Hence, experimental measurements of the full band structure of the copper on silicon interface, for example by EMS, have the potential to reveal the chemistry of the interface in a detailed way

  20. Copper laser diagnostics and kinetics support

    International Nuclear Information System (INIS)

    1981-12-01

    In the effort MSNW participated with the LINL copper-Vapor Laser Program by providing a useful plasma diagnostic for interpretation of Copper-vapor laser kinetics. MSNW developed and delivered a pulsed interferometric diagnostic package to LLNL. Moreover MSNW provided personal services at the request and direction of LLL in the implementation of the diagnostic and interpretation of the data

  1. Differential bacteriophage mortality on exposure to copper.

    Science.gov (United States)

    Li, Jinyu; Dennehy, John J

    2011-10-01

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

  2. Mixed-ligand binuclear copper(II)

    Indian Academy of Sciences (India)

    A new mixed-ligand binuclear copper(II) complex [Cu(MS)(bpy)]2.(ClO4)2, built of 5-methylsalicylaldehyde and 2,2'-bipyridyl has been synthesized and characterized by using elemental analysis, IR and UV-Vis spectroscopy. Crystal structure of the complex shows that copper(II) ion lies in a square pyramidal coordination ...

  3. Copper transporters and chaperones: Their function on ...

    Indian Academy of Sciences (India)

    2016-08-02

    Aug 2, 2016 ... This micronutrient is necessary for the proper growth, development and maintenance of connective tissue, bone, brain and heart. Copper is found to ... Wilson's disease. (WD) is a monogenic, autosomal, recessive inherited disor- der where the copper ATPase, ATP7B, is a major causative gene (Tanzi et al.

  4. Copper Regulates Cyclic AMP-Dependent Lipolysis

    Science.gov (United States)

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

    2016-01-01

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

  5. High Copper Amalgam Alloys in Dentistry

    Directory of Open Access Journals (Sweden)

    Gaurav Solanki

    2012-07-01

    Full Text Available Amalgam Restoration is an example of the material giving its name to the process. Amalgam fillings are made up of mercury, powdered silver and tin. They are mixed and packed into cavities in teeth where it hardens slowly and replaces the missing tooth substance. The high copper have become material of choice as compared to low copper alloys nowadays because of their improved mechanical properties, corrosion resistance, better marginal integrity and improved performance in clinical trial. The high copper amalgam was used as a restorative material. The application of high copper amalgam was found to be much more useful than low copper amalgam. High copper had much more strength, corrosion resistance, durability and resistance to tarnish as compared to low copper amalgams. No marked expansion or condensation was noted in the amalgam restoration after its setting after 24 hrs. By using the high copper alloy, the chances of creep were also minimized in the restored tooth. No discomfort or any kind of odd sensation in the tooth was noted after few days of amalgam restoration in the tooth.

  6. Lead and Copper Control 101-slides

    Science.gov (United States)

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

  7. Synthesis and optical characterization of copper nanoparticles ...

    Indian Academy of Sciences (India)

    Hence, copper (Cu) colloidal NPs were prepared using laser ablation (Nd:YAG, ... Copper nanoparticles; optical property; LSPR, laser ablation. 1. Introduction. Among all nanomaterials, nanoparticles (NPs) are of great interest because of their optical, structural, ... useful for applications in a wide range of fields like can-.

  8. Modification of polycrystalline copper by proton irradiation

    International Nuclear Information System (INIS)

    Garcia S, F.; Cabral P, A.; Saniger B, J.M.; Banuelos, J.G.; Barragan V, A.

    1997-01-01

    Polished copper samples were irradiated with proton beams of 300 and 700 keV at room temperature and at -150 Centigrade. In this work the obtained results are reported when such copper irradiated samples are analysed with Sem, Tem, AFM. The Sem micrographs showed evident changes in surface of these copper samples, therefore an EDAX microanalysis was done for its characterization. additionally, the Tem micrographs showed heaps formation until 200 nm. Its electron diffraction spectra indicated that these heaps consist of a copper compound. Finally with AFM were observed changes in coloration of the irradiated sample surface, as well as changes in texture and rugosity of them. These results show in general that irradiation process with protons which is known as an innocuo process produces changes in the copper properties. (Author)

  9. Refining processes in the copper casting technology

    Directory of Open Access Journals (Sweden)

    S. Rzadkosz

    2015-01-01

    Full Text Available The paper presents the analysis of technology of copper and alloyed copper destined for power engineering casts. The casts quality was assessed based on microstructure, chemical content analysis and strength properties tests. Characteristic deoxidising (Logas, Cup and modifying (ODM2, Kupmod2 formulas were used for the copper where high electrical conductivity was required. Chosen examples of alloyed copper with varied Cr and Zr content were studied, and the optimal heat treatment parameters were tested for a chosen chromium copper content, based on the criterion of hardness and electrical conductivity tests. Searching for materials with high wear resistance, the influence of variable silicone content on the properties of CuNiSi alloy was researched.

  10. Activation of ADAM 12 protease by copper

    DEFF Research Database (Denmark)

    Loechel, F; Wewer, Ulla M.

    2001-01-01

    Conversion of latent proteases to the active form occurs by various mechanisms characteristic for different protease families. Here we report that the disintegrin metalloprotease ADAM 12-S is activated by Cu(II). Copper activation is distinct from the cysteine switch component of latency: elimina......Conversion of latent proteases to the active form occurs by various mechanisms characteristic for different protease families. Here we report that the disintegrin metalloprotease ADAM 12-S is activated by Cu(II). Copper activation is distinct from the cysteine switch component of latency......: elimination of the ADAM 12 cysteine switch by a point mutation in the propeptide had no effect on copper activation, whereas mutation of an unpaired cysteine residue in the catalytic domain resulted in a mutant form of ADAM 12-S that was insensitive to copper. This suggests a multi-step activation mechanism...... for ADAM 12 involving both furin cleavage and copper binding....

  11. Copper nitrate: a privileged reagent for organic synthesis.

    Science.gov (United States)

    Gao, Mingchun; Ye, Rongxuan; Shen, Weijia; Xu, Bin

    2018-04-18

    Copper has been explored as an ideal candidate for replacing noble metals in organic synthesis, especially for practical large scale preparation. Recent decades have witnessed the renaissance and improvement of copper-catalyzed and copper-mediated organic reactions. Copper nitrate is a common inorganic copper salt which has been proved to be a ubiquitous reactant in organic synthesis due to its commercial availability, stability, inexpensiveness and environmentally benign nature. Copper nitrate could be used as a nitration reagent, oxidant, catalyst or promoter, and Lewis acid as well. Remarkably, great attention has been devoted to the efficient transformation of copper nitrate into functionalized or complicated compounds through various reaction types including cyclization, C-H activation, difunctionalization, nitration, rearrangement and asymmetric synthesis with chiral ligands. Further modification of copper nitrate, such as solid-supported copper nitrate or copper nitrate complexes, extends its applications in organic synthesis. The present review highlights recent advances of copper nitrate in organic synthesis, along with the mechanisms.

  12. 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

  13. 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.

  14. Technical note 4. Corrosion of copper canister

    International Nuclear Information System (INIS)

    Szakalos, Peter; Seetharaman, Seshadri

    2012-06-01

    Objectives of the project: In this review assignment, SKB's treatment of copper corrosion processes or mechanisms in SR-Site shall be reviewed both for the anticipated oxic and anoxic repository environments. The reviewer(s) shall consider if corrosion and corrosion mechanisms of the copper canisters in different possible evolutionary repository environments have been properly described. The objectives of this initial review phase in the area of copper corrosion is to achieve a broad coverage of SR-Site and its supporting references and in particular identify the need for complementary information and clarifications to be delivered by SKB. Summary by the authors: It is expected that the inflow of ground water to the deposition holes and tunnels in the Forsmark repository will be very slow. Thus, it might take some few hundred years up to thousand years before the deposition holes are filled with ground water and it might take 6000 years or more before the bentonite buffer is fully water saturated and pressurized. The copper canisters will therefore meet to two completely different environments: 1. An initial period of several hundreds of years when copper is exposed to gaseous corrosion. 2. And then to aqueous corrosion. From a corrosion point of view the first 1000 years are the most critical for the copper canister since pure, or phosphorus alloyed copper, is not designed to cope with corrosion at elevated temperatures. The outer copper surface temperature is expected to reach 100 deg C within some decades after closure of the repository and then slowly cool down to around 50 deg C after 1000 years. The gaseous corrosion is treated in SKB's safety assessment as being only dependent on oxygen gas and thus easily estimated by an oxygen mass-balance calculation. This simple model has no scientific support since several corrosive trace gases, such as sulphurous and nitrous compounds, operates together with water molecules (moisture) and the corrosion product consists

  15. Grain boundary corrosion of copper canister material

    International Nuclear Information System (INIS)

    Fennell, P.A.H.; Graham, A.J.; Smart, N.R.; Sofield, C.J.

    2001-03-01

    The proposed design for a final repository for spent fuel and other long-lived residues in Sweden is based on the multi-barrier principle. The waste will be encapsulated in sealed cylindrical canisters, which will then be placed in granite bedrock and surrounded by compacted bentonite clay. The canister design is based on a thick cast inner container fitted inside a corrosion-resistant copper canister. During fabrication of the outer copper canisters there will be some unavoidable grain growth in the welded areas. As grains grow they will tend to concentrate impurities within the copper at the new grain boundaries. The work described in this report was undertaken to determine whether there is any possibility of enhanced corrosion at grain boundaries within the copper canister. The potential for grain boundary corrosion was investigated by exposing copper specimens, which had undergone different heat treatments and hence had different grain sizes, to aerated artificial bentonite-equilibrated groundwater with two concentrations of chloride, for increasing periods of time. The degree of grain boundary corrosion was determined by atomic force microscopy (AFM) and optical microscopy. AFM showed no increase in grain boundary 'ditching' for low chloride groundwater. In high chloride groundwater the surface was covered uniformly with a fine-grained oxide. No increases in oxide thickness were observed. No significant grain boundary attack was observed using optical microscopy either. The work suggests that in aerated artificial groundwaters containing chloride ions, grain boundary corrosion of copper is unlikely to adversely affect SKB's copper canisters

  16. Pilot plant for biohidrometallurgical production of copper

    Directory of Open Access Journals (Sweden)

    Conić Vesna T.

    2009-01-01

    Full Text Available In this work, technical and technological characteristics of pilot plant for biohydrometallurgical production of copper financed by Ministry of Science and Environment Protection of Serbia, in the frame of capital providing for scientific research for the period 2006-2008 is presented. Presented within this project is the contribution and capability of the Institute for Mining and Metallurgy Bor to carry out the Fp6 IP project: 'Biotechnology for Metal Bearing Materials in Europe (BioMinE'. In the pilot plant, processes such as: microbiological leaching, pressures oxidation, chemical purification of solutions, solvent extraction and electrowining of copper were carried out. Bioleaching can treat complex copper concentrates which are either unacceptable to smelting or attract high penalties. Some of the elements penalized in smelting (for example zinc are dissolved in the bioleach process and can be recovered for sale. This may often allow an increased recovery of a few percent in the production of the copper concentrate. Bioleaching can be used in either small or large cathodic copper production from copper concentrate. Bioleaching uses conventional upstream and downstream process technology and the unit operation itself has been proven in the gold industry. For these reasons, this work describes the pilot plant for biotechnological production of copper from RTB Bor resources.

  17. Thermal enrichment and speciation of copper in rice husk ashes.

    Science.gov (United States)

    Wei, Yu-Ling; Hu, Ming-Jan; Peng, Yen-Hsun

    2010-12-15

    Copper(II) was considerably enriched in the residual ash via thermal treatment of copper-sorbed rice husk at 700-1100°C for 2h, and the copper speciation was quantitatively determined with X-ray absorption spectroscopy. After the thermal process, the resulting ash only represents by weight 18.7-26.4% of the pre-heated samples. Copper content in the ashes is >7% which is far above the required minimum copper content in copper ores for the copper smelting sector, 0.5%. Crystalline SiO(2) is observed only in the ash generated at 1100°C, with more copper in this ash being available for leaching in acidic solution. It is suggested that this is due to the considerable dissimilarity in crystalline structure between copper compounds and crystalline SiO(2). No chemical reaction between copper and SiO(2) is observed in any ash. In fact, we suggest that the SiO(2) crystalline phase repels copper during the thermal process; this would make it easy to extract copper from the ashes. For copper speciation in the ashes, CuO merely represents 0-12% of the total copper, while Cu(2)O and Cu(0) represent 34-42% and 46-63%, respectively. The lower copper oxidation state would be beneficial for the copper smelting process due to less usage of coke. Copyright © 2010 Elsevier B.V. All rights reserved.

  18. Effects of Copper Exchange Levels on Complexation of Ammonia in ...

    African Journals Online (AJOL)

    NJD

    At low copper exchange levels (<5 copper atoms per unit cell), the major complex is [Cu(Ozeo)2(NH3)2]2+ and ... amount of ammonia. KEYWORDS. Cation exchange, catalysis, copper, complexation, copper ammines. 1. .... at a 4 kHz MAS spinning rate on a Bruker AC 300 NMR spectro- meter (Fitchburg, MA, USA) at 7.05 ...

  19. Effect of aging on copper nanoparticles synthesized by pulsed laser ...

    Indian Academy of Sciences (India)

    Administrator

    2009-06-23

    Jun 23, 2009 ... using 1064 nm wavelength of pulsed Nd : YAG laser. The present paper deals with synthesis of copper and copper oxide nanoparticles by pulsed laser ablation in water and effect of aging on these nanoparticles. 2. Experimental. To produce the copper nanoparticles, a piece of copper metal (99⋅99% ...

  20. The various faces of copper in laboratory animals

    NARCIS (Netherlands)

    Wolf, Ingeborg Désirée de

    2001-01-01

    All research described in this thesis focuses on the role of copper in various biochemical processes. It appears that copper has various faces in laboratory animals. On the one hand, copper is an essential trace element, which implicates that a certain requirement for copper exists. On the other

  1. Copper accumulation by stickleback nests containing spiggin.

    Science.gov (United States)

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

    2016-07-01

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

  2. Copper homeostasis in Mycobacterium tuberculosis.

    Science.gov (United States)

    Shi, Xiaoshan; Darwin, K Heran

    2015-06-01

    Copper (Cu) is a trace element essential for the growth and development of almost all organisms, including bacteria. However, Cu overload in most systems is toxic. Studies show Cu accumulates in macrophage phagosomes infected with bacteria, suggesting Cu provides an innate immune mechanism to combat invading pathogens. To counteract the host-supplied Cu, increasing evidence suggests that bacteria have evolved Cu resistance mechanisms to facilitate their pathogenesis. In particular, Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis, has evolved multiple pathways to respond to Cu. Here, we summarize what is currently known about Cu homeostasis in Mtb and discuss potential sources of Cu encountered by this and other pathogens in a mammalian host.

  3. Inducible plasmid-mediated copper resistance in Escherichia coli.

    Science.gov (United States)

    Rouch, D; Camakaris, J; Lee, B T; Luke, R K

    1985-04-01

    The copper resistance in Escherichia coli determined by plasmid pRJ1004 is inducible. The level of resistance is proportional to the inducing dose of copper. The level of copper resistance in induced and uninduced cells changes with the growth phase of the culture. Induced resistant cells accumulate less copper than uninduced cells, so that reduced accumulation may be the mechanism of resistance. We propose that the inducible plasmid-coded copper resistance interacts with the normal metabolism of the cell to protect against toxic levels of copper while allowing continued operation of copper-dependent functions.

  4. Copper delivery to chloroplast proteins and its regulation

    Directory of Open Access Journals (Sweden)

    Guadalupe eAguirre

    2016-01-01

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

  5. Copper doped borate dosimeters revisited

    Energy Technology Data Exchange (ETDEWEB)

    Alajerami, Y.S.M. [Department of Physics, Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia); Department of Medical Radiography, Al-Azhar University, Gaza Strip, Palestine (Country Unknown); Hashim, S., E-mail: suhairul@utm.my [Department of Physics, Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia); Oncology Treatment Centre, Sultan Ismail Hospital, 81100 Johor Bahru (Malaysia); Ghoshal, S.K. [Department of Physics, Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia); Bradley, D.A. [Centre for Nuclear and Radiation Physics, Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur (Malaysia); Mhareb, M. [Department of Physics, Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia); Saleh, M.A. [Department of Physics, Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia); National Atomic Energy Commission (NATEC), Sana' a (Yemen)

    2014-11-15

    We render a panoramic overview on copper (Cu) doped borate dosimeters. Preparing a dosimeter by mixing specific materials with precise weights and methods is a never-ending quest. The recommended composition is highly decisive for accurate estimation of the absorbed dose, prediction of the biological outcome, determination of the treatment dose for radiation therapy and facilitation of personal monitoring. Based on these principles, the proposed dosimeter must cover a series of dosimetric properties to realize the exact results and assessment. The doped borate dosimeters indeed demonstrate attractive thermoluminescence (TL) features. Several dedicated efforts are attempted to improve the luminescence properties by doping various transition metals or rare-earth elements. The Cu ion being one of the preferred activators shows excellent TL properties as revealed via detail comparison with other dosimeters. Two oxide states of Cu (Cu{sup +} and Cu{sup ++}) with reasonable atomic number allow easy interaction with boron network. Interestingly, the intrinsic luminescent centers of borate lattice are in cross linked with that of Cu{sup +} ions. Thus, the activation of borate dosimeter with Cu ions for the enhancement of the TL sensitivity is recognized. These dosimeters reveal similar glow curves as the standard TLD-100 (LiF:Mg,Ti) one irrespective of the use of modifiers and synthesis techniques. They display high sensitivity, low fading, dose response linearity over wide range and practical minimum detectable dose. Furthermore, the effective atomic number being the most beneficial aspect (equivalent to that of human tissue) of borate dosimeters do not show any change due to Cu ion activations. The past development, major challenges, excitement, applications, recent progress and the future promises of Cu doped borate TL dosimeters are highlighted. - Highlights: • The manuscript gives a panoramic overview on copper doped borate dosimeters. • Cu ions activated

  6. Copper doped borate dosimeters revisited

    International Nuclear Information System (INIS)

    Alajerami, Y.S.M.; Hashim, S.; Ghoshal, S.K.; Bradley, D.A.; Mhareb, M.; Saleh, M.A.

    2014-01-01

    We render a panoramic overview on copper (Cu) doped borate dosimeters. Preparing a dosimeter by mixing specific materials with precise weights and methods is a never-ending quest. The recommended composition is highly decisive for accurate estimation of the absorbed dose, prediction of the biological outcome, determination of the treatment dose for radiation therapy and facilitation of personal monitoring. Based on these principles, the proposed dosimeter must cover a series of dosimetric properties to realize the exact results and assessment. The doped borate dosimeters indeed demonstrate attractive thermoluminescence (TL) features. Several dedicated efforts are attempted to improve the luminescence properties by doping various transition metals or rare-earth elements. The Cu ion being one of the preferred activators shows excellent TL properties as revealed via detail comparison with other dosimeters. Two oxide states of Cu (Cu + and Cu ++ ) with reasonable atomic number allow easy interaction with boron network. Interestingly, the intrinsic luminescent centers of borate lattice are in cross linked with that of Cu + ions. Thus, the activation of borate dosimeter with Cu ions for the enhancement of the TL sensitivity is recognized. These dosimeters reveal similar glow curves as the standard TLD-100 (LiF:Mg,Ti) one irrespective of the use of modifiers and synthesis techniques. They display high sensitivity, low fading, dose response linearity over wide range and practical minimum detectable dose. Furthermore, the effective atomic number being the most beneficial aspect (equivalent to that of human tissue) of borate dosimeters do not show any change due to Cu ion activations. The past development, major challenges, excitement, applications, recent progress and the future promises of Cu doped borate TL dosimeters are highlighted. - Highlights: • The manuscript gives a panoramic overview on copper doped borate dosimeters. • Cu ions activated technique in borate

  7. Transport coefficients in copper vapor arc plasmas

    International Nuclear Information System (INIS)

    Rahal, A.M.; Rahhaoui, B.; Vacquie, S.

    1985-01-01

    The presence of copper vapors modifies the properties of arc discharges. The paper deals with a region not investigated earlier, where in the core of the positive column of very short or high current arcs there is a high copper concentration. At these values the relative losses take a greater part in the energy balance. Using the charged-charged collision integrals, the transport coefficients (axial temperature, thermal and electric conductivity, viscosity) of the plasma with higher copper vapor concentration are calculated as the function of the arc current intensity. (D.Gy.)

  8. Study of laser welding of copper sheets

    OpenAIRE

    A. Klimpel; A. Rzeźnikiewicz; Ł. Janik

    2007-01-01

    Purpose: Purpose of this research is to study laser autogenous welding process of short seam beads and filletwelds of lap joints of oxygen-free copper sheets 1.0 [mm] thick. On the bases of results of quality assessment itwas proved that high power diode laser (HPDL) welded lap joints of copper sheet provide mechanical propertieson the level of parent material.Design/methodology/approach: Short seam beads and fillet welds of lap joints of oxygen-free copper sheets 1,0[mm] thick were tested, t...

  9. 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...... waveguides and test sensitivity of surface plasmon resonances. Our results are likely to initiate wide use of graphene-protected plasmonics....

  10. Cementation of silver ions on metallic copper

    International Nuclear Information System (INIS)

    Jaskula, M.

    2009-01-01

    The silver cementation on metallic copper was investigated in the presence or absence of oxygen. The influence of sulphuric acid and copper sulphate concentration on the silver cement morphology was studied in details, and results were linked with the previously determined kinetics data of the process. The morpgology of silver depopsit was found to be independent of the prosence of oxygen in the system in as well as the sulphuric acide concentration. Contrary, the concentration of copper sulphate strongly influenced the morphology of silver deposite. Two-stage mechanism of cementation was proposed. (authors).

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

    Science.gov (United States)

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

    2011-01-01

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

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

    Science.gov (United States)

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

    2011-01-01

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

  13. Effects of organic matters coming from Chinese tea on soluble copper release from copper teapot

    International Nuclear Information System (INIS)

    Ni Lixiao; Li Shiyin

    2008-01-01

    The morphology and elemental composition of the corrosion products of copper teapot's inner-surface were characterized by the scanning electron microscopy and energy dispersive X-ray surface analysis (SEM/EDS), X-ray powder diffraction (XRD) and X-ray photon spectroscopy (XPS) analysis. It was revealed that Cu, Fe, Ca, P, Si and Al were the main elements of corrosion by-products, and the α-SiO 2 , Cu 2 O and CaCO 3 as the main mineral components on the inner-surface of copper teapot. The effects of organic matters coming from Chinese tea on soluble copper release from copper teapots in tap water were also investigated. The results showed that the doses of organic matter (as TOC), temperate and stagnation time have significant effects on the concentration of soluble copper released from copper teapots in tap water

  14. The Effective Electrolytic Recovery of Dilute Copper from Industrial Wastewater

    Directory of Open Access Journals (Sweden)

    Teng-Chien Chen

    2013-01-01

    Full Text Available Electroplating copper industry was discharged huge amount wastewater and cause serious environmental and health damage in Taiwan. This research applied electrical copper recovery system to recover copper metal. In this work, electrotreatment of a industrial copper wastewater ([Cu] = 30000 mg L−1 was studied with titanium net coated with a thin layer of RuO2/IrO2 (DSA reactor. The optimal result for simulated copper solution was 99.9% copper recovery efficiency in current density 0.585 A/dm2 and no iron ion. Due to high concentration of iron and chloride ions in real industrial wastewater, the copper recovery efficiency was down to 60%. Although, the copper recovery efficiency was not high as simulated copper solution, high environmental economic value was included in the technology. The possibility of pretreating the wastewater with iron is the necessary step, before the electrical recovery copper system.

  15. The evaluation of corrosion inhibitors for application to copper and copper alloy archaeological artefacts

    OpenAIRE

    Faltermeier, R.

    1995-01-01

    This thesis concerns corrosion inhibiting compounds which slow the deterioration of archaeological copper artefacts. Benzotriazole (BTA) and 2-Amino- 5-mercapto-1,3,4-thiadiazole (AMT) have been applied as corrosion inhibitors in archaeological conservation. A search was conducted for similar compounds that could be applied in the conservation of copper and copper alloys. According to a list of requirements specific to archaeological conservation, six new inhibitors were tes...

  16. Copper toxicity in sheep: the effects of repeated intravenous injections of copper sulphate

    Energy Technology Data Exchange (ETDEWEB)

    Howell, J.M.; Gopinath, C.

    1977-01-01

    Four Clun Forest, Suffolk cross sheep were given daily intravenous injections of copper sulphate. Three similar sheep acted as controls. The copper dosed sheep developed haemolysis and showed liver, kidney and brain damage similar to that seen in chronic copper poisoning. All animals survived for 30 days and two would have lived longer. Reticulocytes were produced after four days and continued to be produced, sometimes in high numbers throughout the course of the experiment. 21 references, 6 figures, 2 tables.

  17. Analysis of copper flows in China from 1975 to 2010.

    Science.gov (United States)

    Zhang, Ling; Yang, Jiameng; Cai, Zhijian; Yuan, Zengwei

    2014-04-15

    By applying substance flow analysis (SFA), the paper attempts to illustrate how copper utilization pattern has changed in the anthroposphere of China from 1975 to 2010. An analytical framework is firstly established and the detailed copper cycles of the specific years 1975, 1985, 1995, 2005 and 2010 are then characterized. Major conclusions include the following: (1) Chinese copper industry has made significant progress driven by large domestic copper demand since 1970s, especially after 1990s. Also the structure of copper industry has shifted from a basic industry to a processing industry. The share of secondary copper production in total refined copper has risen from 20% in 1975 to 38% in 2010; (2) the Chinese society has experienced a rapid copper accumulation since 1990s. The annual input flow to use stage jumped from only 334 Gg (that is 0.36 kg per capita copper consumption) in 1975 to 7,916 Gg (5.90 kg per capita) in 2010; (3) a large amount of copper has to be imported to meet the huge demand, mainly involving in copper concentrate, refined copper and copper scrap. And the NIR (Net Import Ratio) of the three was 53.0%, 38.7% and 63.0% in 2010, respectively; (4) domestically produced copper scrap increased from 74.5 Gg in 1975 to 711.2 Gg in 2010. Comparing it with import scrap and domestic new scrap we found that at current stage the in-use stock is still too small to generate high quantities of copper scrap for domestic secondary copper production. (5) Major copper losses occurred through copper Mining, Refining and WM&R, with the Mining exhibited the lowest copper utilization efficiency (CUE) among the three processes, and may have the great potential for increasing copper utilization rate in China. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

  18. 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...

  19. Transgenic Nicotiana tabacum plants expressing a fungal copper transporter gene show enhanced acquisition of copper.

    Science.gov (United States)

    Singh, Sudhir; Korripally, Premsagar; Vancheeswaran, Ramachandran; Eapen, Susan

    2011-10-01

    The diets of two-thirds of the world's population are deficient in one or more essential elements and one of the approaches to enhance the levels of mineral elements in food crops is by developing plants with ability to accumulate them in edible parts. Besides conventional methods, transgenic technology can be used for enhancing metal acquisition in plants. Copper is an essential element, which is often deficient in human diet. With the objective of developing plants with improved copper acquisition, a high-affinity copper transporter gene (tcu-1) was cloned from fungus Neurospora crassa and introduced into a model plant (Nicotiana tabacum). Integration of the transgene was confirmed by Southern blot hybridization. Transgenic tobacco plants (T(0) and T(1)) expressing tcu-1, when grown in hydroponic medium spiked with different concentrations of copper, showed higher acquisition of copper (up to 3.1 times) compared with control plants. Transgenic plants grown in soil spiked with copper could also take up more copper compared with wild-type plants. Supplementation of other divalent cations such as Cd(2+) and Zn(2+) did not alter uptake of Cu by transgenic plants. The present study has shown that expression of a heterologous copper transporter in tobacco could enhance acquisition of copper.

  20. 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.

  1. Effort on calibration of infrared spark ablation of copper with synthetic copper standards

    Energy Technology Data Exchange (ETDEWEB)

    Wienold, Julia, E-mail: julia.wienold@bam.de; Traub, Heike; Bresch, Harald; Seeger, Stefan; Recknagel, Sebastian; Kipphardt, Heinrich

    2011-06-15

    Two types of copper samples, compact certified copper reference materials and calibration samples prepared from liquid doped, pressed copper powders, were studied in terms of accuracy of obtained calibration functions originating from infrared spark ablation. Additionally, corresponding particle size distributions of the aerosols from infrared spark ablation were recorded. It is shown that the differences in quantification results, originating from the two sets of calibration functions, could not mainly be ascribed to different particle size distributions of the two copper sample types. Possible other causes, as different ablation rates, parts of melting and differences of the chemical constitutions of the two sample types were explored.

  2. Electrodialytic remediation of copper mine tailings

    DEFF Research Database (Denmark)

    Hansen, Henrik K.; Rojo, A.; Ottpsen, Lisbeth M.

    2005-01-01

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

  3. Thermally modified bentonite clay for copper removal

    International Nuclear Information System (INIS)

    Bertagnolli, C.; Kleinübing, S.J.; Silva, M.G.C.

    2011-01-01

    Bentonite clay coming from Pernambuco was thermally modified in order to increase its affinity and capacity in the copper removal in porous bed. The application of this procedure is justified by the low cost of clay, their abundance and affinity for various metal ions. Thermally treatment modifies the clay adsorption properties enables its use in porous bed system, with the increase in surface area and mechanical strength. The material was characterized by x-ray diffraction, thermogravimetric analysis and N 2 physisorption. Then tests were carried out for adsorption of copper in various experimental conditions and evaluated the mass transfer zone, useful and total adsorbed removal amounts and total copper removal percentage. The results showed that the clay treated at higher temperature showed higher copper removal. (author)

  4. Copper catalysed synthesis of indolylquinazolinone alkaloid ...

    Indian Academy of Sciences (India)

    We describe the total synthesis of indolylquinazolinone alkaloid bouchardatine and some of the quinazolinone derivatives. The aerobic oxidation induced by copper(I) bromide, followed by Vilsmeier-Haack formylation gives the natural product bouchardatine alkaloid in good yield.

  5. Purity test for copper-plating solutions

    Science.gov (United States)

    Mansfeld, F. B.

    1977-01-01

    Electrode configuration can be used to measure extent of impurities in acid-copper plating solution. It can be inserted into any plating tank and will show whether bath is clean or contaminated, within fifteen minutes.

  6. Ultralow-loss CMOS copper plasmonic waveguides

    DEFF Research Database (Denmark)

    Fedyanin, Dmitry Yu.; Yakubovsky, Dmitry I.; Kirtaev, Roman V.

    2016-01-01

    with microelectronics manufacturing technologies. This prevents plasmonic components from integration with both silicon photonics and silicon microelectronics. Here, we demonstrate ultralow-loss copper plasmonic waveguides fabricated in a simple complementary metal-oxide semiconductor (CMOS) compatible process, which...

  7. Electroless Copper Deposition: A Sustainable Approach

    Science.gov (United States)

    Kutnahorsky, Marika Renee

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

  8. Antimicrobial Properties of Copper Nanoparticles and Amino Acid Chelated Copper Nanoparticles Produced by Using a Soya Extract

    OpenAIRE

    DeAlba-Montero, I.; Guajardo-Pacheco, Jes?s; Morales-S?nchez, Elpidio; Araujo-Mart?nez, Rene; Loredo-Becerra, G. M.; Mart?nez-Casta??n, Gabriel-Alejandro; Ruiz, Facundo; Compe?n Jasso, M. E.

    2017-01-01

    This paper reports a comparison of the antibacterial properties of copper-amino acids chelates and copper nanoparticles against Escherichia coli, Staphylococcus aureus, and Enterococcus faecalis. These copper-amino acids chelates were synthesized by using a soybean aqueous extract and copper nanoparticles were produced using as a starting material the copper-amino acids chelates species. The antibacterial activity of the samples was evaluated by using the standard microdilution method (CLSI M...

  9. Treatment of Copper Converter Flue Dust for the Separation of Metallic/non-metallic Copper by Hydrometallurgical Processing

    OpenAIRE

    Martín, M. I.; López-Delgado, Aurora; López Gómez, Félix Antonio; Gómez Coedo, Aurora; Dorado López, María Teresa; Alguacil, Francisco José

    2003-01-01

    A hydrometallurgical procedure for the separation of copper soluble species from metallic copper of a copper converter flue dust was studied. The high content of metallic copper in the starting material made unique a procedure of such characteristics for the treatment of this secondary copper resource. The procedure consists of leaching and solvent extraction operations. Leaching was carried out under atmospheric conditions using sulphuric acid. Under various experimental conditions the metal...

  10. Electrodialytic Remediation of Copper Mine Tailings

    DEFF Research Database (Denmark)

    Hansen, H.K.; Rojo, A.; Ottosen, L.M.

    2012-01-01

    This work compares and evaluates sixteen electrodialytic laboratory remediation experiments on copper mine tailings. Different parameters were analysed, such as remediation time, addition of desorbing agents, and the use of pulsed electrical fields.......This work compares and evaluates sixteen electrodialytic laboratory remediation experiments on copper mine tailings. Different parameters were analysed, such as remediation time, addition of desorbing agents, and the use of pulsed electrical fields....

  11. Pharmacological Properties of Nanometals (Silver, Copper, Iron

    Directory of Open Access Journals (Sweden)

    Chekman, I.S.

    2015-01-01

    Full Text Available The article summarizes the results of studies on the pharmacological, toxicological and specific properties of nanometals (silver, iron, copper. It is established that nanoparticles of silver, copper, iron exhibit antimicrobial action. Acute toxicity of nanometals depends on their nature, administration route and animal sex. Effects on heart activity and hemodynamic status as well as erythrocyte osmotic fragility have dose-dependent nature.

  12. Bioremediation: Copper Nanoparticles from Electronic-waste

    OpenAIRE

    D. R. MAJUMDER

    2012-01-01

    A single-step eco-friendly approach has been employed to synthesize copper nanoparticles. The superfast advancement in the field of electronics has given rise to a new type of waste called electronic waste. Since the physical and chemical recycling procedures have proved to be hazardous, the present work aims at the bioremediation of e-waste in order to recycle valuable metals. Microorganisms such as Fusarium oxysporum and Pseudomonas sp. were able to leach copper (84-130 nm) from integrated ...

  13. Atomistic simulations of dislocation processes in copper

    DEFF Research Database (Denmark)

    Vegge, T.; Jacobsen, K.W.

    2002-01-01

    We discuss atomistic simulations of dislocation processes in copper based on effective medium theory interatomic potentials. Results on screw dislocation structures and processes are reviewed with particular focus on point defect mobilities and processes involving cross slip. For example, the sta......We discuss atomistic simulations of dislocation processes in copper based on effective medium theory interatomic potentials. Results on screw dislocation structures and processes are reviewed with particular focus on point defect mobilities and processes involving cross slip. For example...

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

    Science.gov (United States)

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

    2014-05-20

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

  15. Dietary management of labrador retrievers with subclinical hepatic copper accumulation.

    Science.gov (United States)

    Fieten, H; Biourge, V C; Watson, A L; Leegwater, P A J; van den Ingh, T S G A M; Rothuizen, J

    2015-01-01

    Genetic and environmental factors, including dietary copper intake, contribute to the pathogenesis of copper-associated hepatitis in Labrador retrievers. Clinical disease is preceded by a subclinical phase in which copper accumulates in the liver. To investigate the effect of a low-copper, high-zinc diet on hepatic copper concentration in Labrador retrievers with increased hepatic copper concentrations. Twenty-eight clinically healthy, client-owned Labrador retrievers with a mean hepatic copper concentration of 919 ± 477 mg/kg dry weight liver (dwl) that were related to dogs previously diagnosed with clinical copper-associated hepatitis. Clinical trial in which dogs were fed a diet containing 1.3 ± 0.3 mg copper/Mcal and 64.3 ± 5.9 mg zinc/Mcal. Hepatic copper concentrations were determined in liver biopsy samples approximately every 6 months. Logistic regression was performed to investigate effects of sex, age, initial hepatic copper concentration and pedigree on the ability to normalize hepatic copper concentrations. In responders (15/28 dogs), hepatic copper concentrations decreased from a mean of 710 ± 216 mg/kg dwl copper to 343 ± 70 mg/kg dwl hepatic copper after a median of 7.1 months (range, 5.5-21.4 months). Dogs from a severely affected pedigree were at increased risk for inability to have their hepatic copper concentrations normalized with dietary treatment. Feeding a low-copper, high-zinc diet resulted in a decrease in hepatic copper concentrations in a subset of clinically normal Labrador retrievers with previous hepatic copper accumulation. A positive response to diet may be influenced by genetic background. Determination of clinical benefit requires further study. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  16. Comparative genomic analyses of copper transporters and cuproproteomes reveal evolutionary dynamics of copper utilization and its link to oxygen.

    Directory of Open Access Journals (Sweden)

    Perry G Ridge

    2008-01-01

    Full Text Available Copper is an essential trace element in many organisms and is utilized in all domains of life. It is often used as a cofactor of redox proteins, but is also a toxic metal ion. Intracellular copper must be carefully handled to prevent the formation of reactive oxygen species which pose a threat to DNA, lipids, and proteins. In this work, we examined patterns of copper utilization in prokaryotes by analyzing the occurrence of copper transporters and copper-containing proteins. Many organisms, including those that lack copper-dependent proteins, had copper exporters, likely to protect against copper ions that inadvertently enter the cell. We found that copper use is widespread among prokaryotes, but also identified several phyla that lack cuproproteins. This is in contrast to the use of other trace elements, such as selenium, which shows more scattered and reduced usage, yet larger selenoproteomes. Copper transporters had different patterns of occurrence than cuproproteins, suggesting that the pathways of copper utilization and copper detoxification are independent of each other. We present evidence that organisms living in oxygen-rich environments utilize copper, whereas the majority of anaerobic organisms do not. In addition, among copper users, cuproproteomes of aerobic organisms were larger than those of anaerobic organisms. Prokaryotic cuproproteomes were small and dominated by a single protein, cytochrome c oxidase. The data are consistent with the idea that proteins evolved to utilize copper following the oxygenation of the Earth.

  17. Copper accumulation in senescent cells: Interplay between copper transporters and impaired autophagy

    Directory of Open Access Journals (Sweden)

    Shashank Masaldan

    2018-06-01

    Full Text Available Cellular senescence is characterized by irreversible growth arrest incurred through either replicative exhaustion or by pro-oncogenic cellular stressors (radioactivity, oxidative stress, oncogenic activation. The enrichment of senescent cells in tissues with age has been associated with tissue dyshomeostasis and age-related pathologies including cancers, neurodegenerative disorders (e.g. Alzheimer's, Parkinson's, etc. and metabolic disorders (e.g. diabetes. We identified copper accumulation as being a universal feature of senescent cells [mouse embryonic fibroblasts (MEF, human prostate epithelial cells and human diploid fibroblasts] in vitro. Elevated copper in senescent MEFs was accompanied by elevated levels of high-affinity copper uptake protein 1 (Ctr1, diminished levels of copper-transporting ATPase 1 (Atp7a (copper export and enhanced antioxidant defence reflected by elevated levels of glutathione (GSH, superoxide dismutase 1 (SOD1 and glutaredoxin 1 (Grx1. The levels of intracellular copper were further increased in senescent MEFs cultured in copper supplemented medium and in senescent Mottled Brindled (Mobr MEFs lacking functional Atp7a. Finally, we demonstrated that the restoration/preservation of autophagic-lysosomal degradation in senescent MEFs following rapamycin treatment correlated with attenuation of copper accumulation in these cells despite a further decrease in Atp7a levels. This study for the first time establishes a link between Atp7a and the autophagic-lysosomal pathway, and a requirement for both to effect efficient copper export. Such a connection between cellular autophagy and copper homeostasis is significant, as both have emerged as important facets of age-associated degenerative disease. Keywords: Senescence, Copper, Ageing, Homeostasis, Autophagy

  18. Synthesis of the copper chelator TGTA and evaluation of its ability to protect biomolecules from copper induced degradation during copper catalyzed azide-alkyne bioconjugation reactions.

    Science.gov (United States)

    Ekholm, F S; Pynnönen, H; Vilkman, A; Koponen, J; Helin, J; Satomaa, T

    2016-01-21

    One of the most successful bioconjugation strategies to date is the copper(I)-catalyzed cycloaddition reaction (CuAAC), however, the typically applied reaction conditions have been found to degrade sensitive biomolecules. Herein, we present a water soluble copper chelator which can be utilized to protect biomolecules from copper induced degradation.

  19. Phototunable Magnetism in Copper Octacyanomolybdate

    Directory of Open Access Journals (Sweden)

    Jun Ohara

    2014-01-01

    Full Text Available We introduce copper molybdenum cyanides of general formula Cu2[Mo(CN8]·nH2O, which can serve as optofunctional magnetic devices. Their ground states generally stay paramagnetic down to temperatures of the K order but exhibit a spontaneous magnetization upon photoirradiation usually below a few tens of K. To interest us still further, such a ferromagnetic stateinduced by blue-laser irradiation is demagnetized step by step through further application of red or near-infrared laser pulses. We solve this intriguing photomagnetism. The ground-state properties are fully revealed by means of a group-theoretical technique. Taking account of experimental observations, we simulate applying pump laser pulses to a likely ground state and successfully reproduce both the magnetization and demagnetization dynamics. We monitor the photorelaxation process through angle-resolved photoemission spectroscopy. Electrons are fully itinerant in any of the photoinduced steady states, forming a striking contrast to the initial equilibrium state of atomic aspect. The fully demagnetized final steady state looks completely different from the initial paramagnetism but bears good analogy to one of the possible ground states available with the Coulomb repulsion on Cu sites suppressed.

  20. The Copper Balance of Cities

    Science.gov (United States)

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

    2014-01-01

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

  1. Interesting properties of some iron(II), copper(I) and copper(II ...

    Indian Academy of Sciences (India)

    Administrator

    Tridendate ligands with nitrogen centers, generally well-known as the tripod ligands, have been of considerable interest to inorganic chemists dealing with the preparation of model compounds for hemocyanin, tyrosinase etc. We have found that such ligands when complexed with iron(II) and copper(II) and copper(I) ions ...

  2. Preparation of copper and silicon/copper powders by a gas ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 32; Issue 5. Preparation of copper and silicon/copper powders by a gas evaporation-condensation method. J Temuujin S P Bardakhanov A V Nomoev V I Zaikovskii A Minjigmaa G Dugersuren A Van Riessen. Composites Volume 32 Issue 5 October 2009 pp 543-547 ...

  3. copper(I) and copper(II) complexes with tridentate ligands

    Indian Academy of Sciences (India)

    Administrator

    Tridendate ligands with nitrogen centers, generally well-known as the tripod ligands, have been of considerable interest to inorganic chemists dealing with the preparation of model compounds for hemocyanin, tyrosinase etc. We have found that such ligands when complexed with iron(II) and copper(II) and copper(I) ions ...

  4. Effects of Small Additions of Copper and Copper + Nickel on the Oxidation Behavior of Iron

    Science.gov (United States)

    Webler, Bryan; Yin, Lan; Sridhar, Seetharaman

    2008-10-01

    This study was undertaken to investigate the effect of small amounts of copper and copper + nickel additions on the oxidation rate and oxide/metal interface microstructure of iron. Three iron-based alloys were compared: 0.3 wt pct copper, 0.3 wt pct copper-0.1 wt pct nickel, and 0.3 wt pct copper-0.05 wt pct nickel. Alloy samples were oxidized in air at 1150 °C for 60, 300, and 600 seconds. Pure iron oxidized for 300 seconds was used as a reference material. The parabolic oxidation rate for the iron-copper alloy did not differ from that of pure iron, but the parabolic rate for the nickel-containing alloys decreased by a factor of 2. The microstructure of the iron-copper alloy consisted of a thin, copper-rich layer at the oxide/metal interface. Both nickel-containing alloys had perturbed oxide/metal interfaces consisting of alternating solid/liquid regions. The application of ternary alloy interface stability theories show that the perturbed interfaces arise from unequal diffusivities in the solid γ-iron phase. It is suggested that this perturbed interface microstructure causes the observed decrease in oxidation rate, by limiting the iron supply to the oxide.

  5. 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... under subchapter B of this chapter. Flavors that are generally recognized as safe or that are authorized...

  6. Copper Recycling in the United States in 2004

    Science.gov (United States)

    Goonan, Thomas G.

    2009-01-01

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

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

    Science.gov (United States)

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

    2014-05-08

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

  8. Subclinical copper poisoning in asymptomatic people in residential area near copper smelting complex

    Directory of Open Access Journals (Sweden)

    Ehsanollah Sakhaee

    2012-12-01

    Full Text Available Objective: During an outbreak of industrial chronic copper poisoning at least 10 000 sheep died in Kerman, Iran in 2009. Therefore present study was carried out to evaluate the prevalence of subclinical copper toxicosis in asymptomatic people in residential area near copper smelting complex. Methods: A total of 1 20 serum samples were collected from randomly selected individuals during June to December, 2011. Results: The data obtained revealed that serum levels of AST, ALT and ALP were significantly increased in 7.50%, 4.16% and 5.84% of cases respectively. Results showed that serum levels of copper and ceruloplasmin were significantly increased in 4.16% and 5% of cases as well. Conclusions: Findings of the study revealed that health hazards increased with closeness to the copper mine and smelting complex.

  9. 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.

  10. 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.

  11. Copper Toxicity of Four Different Aquaculture Ponds

    Directory of Open Access Journals (Sweden)

    Moshood Mustapha

    2016-11-01

    were done I triplicates. Copper concentrations ranged from 0.01 to 0.10 mg/L, alkalinity ranged from 105 to 245mg/L. Weeks 1 and 12 recorded the highest and lowest Cu2+ concentrations, while lowest and highest alkalinity were obtained in weeks 1 and 12 respectively in all the ponds. Temperature and pH ranged from 29.1 to 35.9°C and 6.35 to 8.03. The trend of copper concentrations in the ponds was Natural > Earthen > Concrete > Collapsible, with concentration slightly above the normal in the ponds. This could have come from the pipes used in delivering water to the pond, copper alloy nets and mesh used in the ponds, anti-fouling agents, algaecides, water source and fish meal. Effect of elevated copper was seen in the morphology and behavior of Clarias gariepinus which include slimy mucus on the skin, aggressive and uncoordinated swimming with the opercula flared, slow growth, reduced odor perception of food and water bubbles on the ponds. Copper should be regularly bio monitored to determine toxicity in fish.

  12. Copper-beryllium alloys for technical applications

    International Nuclear Information System (INIS)

    Heller, W.

    1976-01-01

    Data of physical properties are compiled for the most commonly used copper-beryllium alloys (CuBe 2, CuBe 1.7, CuCoBe, and CuCoAgBe), with emphasis on their temperature dependence and their variation with particular annealing and hardening treatments. The purpose is to provide a reference source and to indicate the versatility of these materials with respect to other copper alloys and to pure copper. The special features of CuBe alloys include high mechanical strength with reasonably high electrical conductivity, as well as good wear and corrosion resistance. For example, CuBe 2 has a yield strength of up to 1200 N/mm 2 , about three times that of pure copper, whilst the electrical conductivity of CuCoBe can be as high as 28 MS/m, nearly half that of pure copper. Typical applications are springs and electrical contacts. The importance of a proper heat treatment is discussed in some detail, notably the metallurgy and effects of low-temperature annealing (precipitation-hardening). A chapter on manufacturing processes covers machining, brazing, welding, and cleaning. This is followed by some remarks on safety precautions against beryllium poisoning. CuBe alloys are commercially available in the form of wires, strips, rods, and bars. Typical dimensions, specifications, a brief cost estimate, and addresses of suppliers are listed. (Author)

  13. Copper in the sea: a bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, R.L.

    1977-04-01

    Life in the sea is vulnerable to the influx of trace metals resulting from man's activities. Although many pollutants introduced to the sea eventually degrade to less harmful forms, trace metals accumulate in sediments and have a continued potential for effect on biota. Copper has a toxic potential exceeding all other metals due to the quantity discharged and its toxicological effect. Fortunately, copper in the oceans is rendered less bioavailable or less toxic by its ready interaction with the complex chemical components of seawater. This bibliography was prepared to illustrate the status of current knowledge of the biogeochemistry of copper and to aid the development of research programs to define the effects of copper discharged to the marine environment. The references are categorized to aid the reader to locate literature concerning specific aspects of the biogeochemistry of copper. A brief comment describing the important findings in each category is given. Although this bibliography is not exhaustive, the listed references are likely representative of current knowledge.

  14. Tetra(3,4-pyrido)porphyrazines Caught in the Cationic Cage: Toward Nanomolar Active Photosensitizers

    Czech Academy of Sciences Publication Activity Database

    Macháček, M.; Demuth, J.; Čermák, P.; Vavrečková, M.; Hrubá, L.; Jedličková, A.; Kubát, Pavel; Šimůnek, T.; Nováková, V.; Zimčík, P.

    2016-01-01

    Roč. 59, č. 20 (2016), s. 9443-9456 ISSN 0022-2623 Institutional support: RVO:61388955 Keywords : TARGETED PHOTODYNAMIC THERAPY * SINGLET OXYGEN * PHOTOPHYSICAL PROPERTIES Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 6.259, year: 2016

  15. Copper Resistance of the Emerging Pathogen Acinetobacter baumannii.

    Science.gov (United States)

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

    2016-10-15

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

  16. 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.

  17. COPPER RESISTANT STRAIN CANDIDA TROPICALIS RomCu5 INTERACTION WITH SOLUBLE AND INSOLUBLE COPPER COMPOUNDS

    Directory of Open Access Journals (Sweden)

    Ie. P. Prekrasna

    2015-10-01

    Full Text Available The focus of the study was interaction of Candida tropicalis RomCu5 isolated from highland Ecuador ecosystem with soluble and insoluble copper compounds. Strain C. tropicalis RomCu5 was cultured in a liquid medium of Hiss in the presence of soluble (copper citrate and CuCl2 and insoluble (CuO and CuCO3 copper compounds. The biomass growth was determined by change in optical density of culture liquid, composition of the gas phase was measured on gas chromatograph, redox potential and pH of the culture fluid was defined potentiometrically. The concentration of soluble copper compounds was determined colorimetrically. Maximal permissible concentration of Cu2+ for C. tropicalis RomCu5 was 30 000 ppm of Cu2+ in form of copper citrate and 500 ppm of Cu2+ in form of CuCl2. C. tropicalis was metabolically active at super high concentrations of Cu2+, despite the inhibitory effect of Cu2+. C. tropicalis immobilized Cu2+ in the form of copper citrate and CuCl2 by it accumulation in the biomass. Due to medium acidification C. tropicalis dissolved CuO and CuCO3. High resistance of C. tropicalis to Cu2+ and ability to interact with soluble and insoluble copper compounds makes it biotechnologically perspective.

  18. Energetics of copper trafficking between the Atx1 metallochaperone and the intracellular copper transporter, Ccc2.

    Science.gov (United States)

    Huffman, D L; O'Halloran, T V

    2000-06-23

    The Atx1 metallochaperone protein is a cytoplasmic Cu(I) receptor that functions in intracellular copper trafficking pathways in plants, microbes, and humans. A key physiological partner of the Saccharomyces cerevisiae Atx1 is Ccc2, a cation transporting P-type ATPase located in secretory vesicles. Here, we show that Atx1 donates its metal ion cargo to the first N-terminal Atx1-like domain of Ccc2 in a direct and reversible manner. The thermodynamic gradient for metal transfer is shallow (K(exchange) = 1.4 +/- 0.2), establishing that vectorial delivery of copper by Atx1 is not based on a higher copper affinity of the target domain. Instead, Atx1 allows rapid metal transfer to its partner. This equilibrium is unaffected by a 50-fold excess of the Cu(I) competitor, glutathione, indicating that Atx1 also protects Cu(I) from nonspecific reactions. Mechanistically, we propose that a low activation barrier for transfer between partners results from complementary electrostatic forces that ultimately orient the metal-binding loops of Atx1 and Ccc2 for formation of copper-bridged intermediates. These thermodynamic and kinetic considerations suggest that copper trafficking proteins overcome the extraordinary copper chelation capacity of the eukaryotic cytoplasm by catalyzing the rate of copper transfer between physiological partners. In this sense, metallochaperones work like enzymes, carefully tailoring energetic barriers along specific reaction pathways but not others.

  19. Characterization of copper-resistant rhizosphere bacteria from Avena sativa and Plantago lanceolata for copper bioreduction and biosorption.

    Science.gov (United States)

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

    2012-04-01

    Copper is a toxic heavy metal widely used to microbial control especially in agriculture. Consequently, high concentrations of copper residues remain in soils selecting copper-resistant organisms. In vineyards, copper is routinely used for fungi control. This work was undertaken to study copper resistance by rhizosphere microorganisms from two plants (Avena sativa L. and Plantago lanceolata L.) common in vineyard soils. Eleven rhizosphere microorganisms were isolated, and four displayed high resistance to copper. The isolates were identified by 16S rRNA gene sequence analysis as Pseudomonas putida (A1), Stenotrophomonas maltophilia (A2) and Acinetobacter sp. (A6), isolated from Avena sativa rhizosphere, and Acinetobacter sp. (T5), isolated from Plantago lanceolata rhizosphere. The isolates displayed high copper resistance in the temperature range from 25°C to 35°C and pH in the range from 5.0 to 9.0. Pseudomonas putida A1 resisted as much as 1,000 mg L(-1) of copper. The isolates showed similar behavior on copper removal from liquid medium, with a bioremoval rate of 30% at 500 mg L(-1) after 24 h of growth. Speciation of copper revealed high copper biotransformation, reducing Cu(II) to Cu(I), capacity. Results indicate that our isolates are potential agents for copper bioremoval and bacterial stimulation of copper biosorption by Avena sativa and Plantago lanceolata.

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

    Science.gov (United States)

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

    2016-08-15

    The effects of confounding by temporal factors remains understudied in pollution ecology. For example, there is little understanding of how disturbance history affects the development of assemblages. To begin addressing this gap in knowledge, marine biofilms were subjected to temporally-variable regimes of copper exposure and depuration. It was expected that the physical and biological structure of the biofilms would vary in response to copper regime. Biofilms were examined by inductively coupled plasma optical emission spectrometry, chlorophyll-a fluorescence and field spectrometry and it was found that (1) concentrations of copper were higher in those biofilms exposed to copper, (2) concentrations of copper remain high in biofilms after the source of copper is removed, and (3) exposure to and depuration from copper might have comparable effects on the photosynthetic microbial assemblages in biofilms. The persistence of copper in biofilms after depuration reinforces the need for consideration of temporal factors in ecology. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. [Subcloning of copper resistance promoters from Escherichia coli].

    Science.gov (United States)

    Liu, Z; Brown, N L

    1997-12-01

    There were two promoters, PpcoA and PpcoE, in the copper resistant determinant from Escherichia coli. Either of them contains the copper box. In order to confirm the importance of copper box in the copper resistance promoters and to study their characteristics, several fragments of both promoters were subcloned using pUCD615 as reporter vector into its SmaI site. The results of restriction endonuclease digestion and the results of reporter gene lux-luciferase activities indicated that both of the Ppco short-lux fusions didn't show any luciferase activities, which indicated that these two fragments (Ppco short) couldn't act as promoters, and thus confirming the copper box was essential to copper resistance. If there were no copper box in the Ppco promoters, there would be no copper resistance in the E. coli.

  2. Metals in Metal Salts: A Copper Mirror Demonstration

    Science.gov (United States)

    Pike, Robert D.

    2010-01-01

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

  3. Surface properties of copper based cermet materials

    International Nuclear Information System (INIS)

    Voinea, M.; Vladuta, C.; Bogatu, C.; Duta, A.

    2008-01-01

    The paper presents the characterization of the surface properties of copper based cermets obtained by two different techniques: spray pyrolysis deposition (SPD) and electrodeposition. Copper acetate was used as precursor of Cu/CuO x cermet. The surface morphology was tailored by adding copolymers of maleic anhydride with controlled hydrophobia. The films morphology of Cu/CuO x was assessed using contact angle measurements and AFM analysis. The porous structures obtained via SPD lead to higher liquid adsorption rate than the electrodeposited films. A highly polar liquid - water is recommended as testing liquid in contact angle measurements, for estimating the porosity of copper based cermets, while glycerol can be used to distinguish among ionic and metal predominant structures. Thus, contact angle measurements can be used for a primary evaluation of the films morphology and, on the other hand, of the ratio between the cermet components

  4. Surface properties of copper based cermet materials

    Energy Technology Data Exchange (ETDEWEB)

    Voinea, M. [The Centre: Product Design for Sustainable Development, Transilvania University of Brasov, Eroilor 29, 500036 (Romania)], E-mail: m.voinea@unitbv.ro; Vladuta, C.; Bogatu, C.; Duta, A. [The Centre: Product Design for Sustainable Development, Transilvania University of Brasov, Eroilor 29, 500036 (Romania)

    2008-08-25

    The paper presents the characterization of the surface properties of copper based cermets obtained by two different techniques: spray pyrolysis deposition (SPD) and electrodeposition. Copper acetate was used as precursor of Cu/CuO{sub x} cermet. The surface morphology was tailored by adding copolymers of maleic anhydride with controlled hydrophobia. The films morphology of Cu/CuO{sub x} was assessed using contact angle measurements and AFM analysis. The porous structures obtained via SPD lead to higher liquid adsorption rate than the electrodeposited films. A highly polar liquid - water is recommended as testing liquid in contact angle measurements, for estimating the porosity of copper based cermets, while glycerol can be used to distinguish among ionic and metal predominant structures. Thus, contact angle measurements can be used for a primary evaluation of the films morphology and, on the other hand, of the ratio between the cermet components.

  5. Preparation of copper nanoparticles by radiation

    International Nuclear Information System (INIS)

    Liu Yajian; Guo Xiongbin; Li Zhaolong; Fu Junjie; Tan Yuanyuan; Zhou Xinyao; Xu Furong

    2013-01-01

    Copper nanoparticles were successfully synthesized by 60 Co-γ radiation with aqueous solution of cupric sulfate under inert nitrogen-purged conditions. Cu nanoparticles were characterized by using X-ray diffraction (XRD), transmission electron microscopy (TEM), laser particle size distribution analyzer (LSPSDA) and differential scanning calorimeter (DSC) techniques, respectively. The effects of solution system, pH, additive of surfactant and absorbed doses on the particle size and its distribution as well as stored stability of Cu naoparticles were investigated. High resolution TEM pictures showed the formation of homogeneous cubic-structured copper nanoparticles with different sizes depends on the synthetic conditions. This new kind of synthesis method shows the excellent stability, which may provide an efficient way to improve the fine tuning of the structure and size of copper nanoparticles. (authors)

  6. 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.

  7. REMOVAL OF COPPER ELECTROLYTE CONTAMINANTS BY ADSORPTION

    Directory of Open Access Journals (Sweden)

    B Gabai

    1997-09-01

    Full Text Available Abstract - Selective adsorbents have become frequently used in industrial processes. Recent studies have shown the possibility of using adsorption to separate copper refinery electrolyte contaminants, with better results than those obtained with conventional techniques. During copper electrorefinning, many impurities may be found as dissolved metals present in the anode slime which forms on the electrode surface, accumulated in the electrolyte or incorporated into the refined copper on the cathode by deposition. In this study, synthetic zeolites, chelating resins and activated carbons were tested as adsorbents to select the best adsorbent performance, as well as the best operating temperature for the process. The experimental method applied was the finite bath, which consists in bringing the adsorbent into contact with a finite volume of electrolyte while controlling the temperature. The concentration of metals in the liquid phase was continuously monitored by atomic absorption spectrophotometry (AAS

  8. Thermodynamic data for copper. Implications for the corrosion of copper under repository conditions

    International Nuclear Information System (INIS)

    Puigdomenech, I.; Taxen, C.

    2000-08-01

    The stability of copper canisters has a central role in the safety concept for the planned nuclear spent fuel repository in Sweden. The corrosion of copper canisters will be influenced by the chemical and physical environment in the near-field of the repository, and thermodynamic equilibrium calculations provide the basis for understanding this system. Thermodynamic data have been selected in this work for solids and aqueous species in the system: Cu - H 2 O - H + - H 2 - F - - Cl - - S 2- - SO 4 2- - NO 3 - - NO 2 - - NH 4 + PO 4 3- - CO 3 2+ . For some reactions and compounds, for which no experimental information on temperature effects was available, entropy and heat capacity values have been estimated. The compiled data were used to calculate thermodynamic equilibria for copper systems up to 100 deg C. The stability of copper in contact with granitic groundwaters has been illustrated using chemical equilibrium diagrams, with he following main conclusions: Dissolved sulphide and O 2 in groundwater are the most damaging components for copper corrosion. If available, HS - will react quantitatively with copper to form a variety of sulphides. However, sulphide concentrations in natural waters are usually low, because it forms sparingly soluble solids with transition metals, including Fe(II), which is wide-spread in reducing environments. Chloride can affect negatively copper corrosion. High concentrations (e.g., [Cl - ]TOT > 60 g/l) may be unfavourable for the general corrosion of copper in combination with in the following circumstances: Low pH ( + . The negative effects of Cl - are emphasised at higher temperatures. The chloride-enhancement of general corrosion may be beneficial for localised corrosion: pitting and stress corrosion cracking. The concept of redox potential, E H , has been found to be inadequate to describe copper corrosion in a nuclear repository. The available amounts of oxidants/reductants, and the stoichiometry of the corrosion reactions are

  9. Copper removal using electrosterically stabilized nanocrystalline cellulose.

    Science.gov (United States)

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

    2015-06-03

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

  10. Copper absorption and copper balance during consecutive periods for rats fed varying levels of dietary copper

    International Nuclear Information System (INIS)

    Stuart, M.A.; Johnson, P.E.

    1986-01-01

    Copper (Cu) balance and absorption were studied to determine the extent to which absorption is dependent on dietary Cu. Over 12 consecutive 5-d metabolic periods, Cu balance was determined for four groups of young growing rats (n = 8) fed modified AIN-76 diets having different levels of added Cu (2.5, 5.0, 10 or 20 micrograms/g). Among groups, mean body weights did not differ over time (P greater than 0.05). There were no significant differences among groups for liver, heart or plasma Cu. Rats in all groups were in positive Cu balance throughout the study. After consuming the experimental diets for 10 d, rats eating 10 or 20 micrograms Cu/g diet showed a more positive Cu balance than did rats in the other groups. This trend continued until d 60. For rats eating 20 micrograms Cu/g diet, balance varied significantly over time. Three test meals labeled with stable 65Cu were fed at d 10, 40 and 50, respectively. Apparent Cu absorption, as determined by fecal monitoring of 65Cu, did not change appreciably over time for rats eating 2.5 or 5.0 micrograms Cu/g diet. A test meal labeled with radioactive 67Cu was fed at d 40. For rats eating 2.5 micrograms Cu/g diet, apparent absorption was higher (31%) than that for all other groups (5.0, 23%; 10, 19%; 20, 16%; P less than 0.05). Absorption values determined by whole-body retention of 67Cu were similar to those determined by fecal monitoring of 65Cu

  11. Copper methanobactin: a molecule whose time has come

    OpenAIRE

    Balasubramanian, Ramakrishnan; Rosenzweig, Amy C.

    2008-01-01

    Copper plays a key role in the physiology of methanotrophs. One way that these bacteria meet their high copper requirement is by the biosynthesis and release of high affinity copper-binding compounds called methanobactins. Recent advances in methanobactin characterization include the first crystal structure, detailed spectroscopic analyses, and studies of metal ion specificity. Methanobactin may function in copper uptake, regulation of methane monooxygenase expression, protection against copp...

  12. The Yin and Yang of Copper During Infection

    Science.gov (United States)

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

    2017-01-01

    Copper is an essential micronutrient for both pathogens and the animal hosts they infect. However, copper can also be toxic in cells due to its redox properties and ability to disrupt active sites of metalloproteins, such as Fe-S enzymes. Through these toxic properties, copper is an effective antimicrobial agent and an emerging concept in innate immunity is that the animal host intentionally exploits copper toxicity in antimicrobial weaponry. In particular, macrophages can attack invading microbes with high copper and this metal is also elevated at sites of lung infection. In addition, copper levels in serum rise during infection with a wide array of pathogens. To defend against this toxic copper, the microbial intruder is equipped with a battery of copper detoxification defenses that promote survival in the host, including copper exporting ATPases and copper binding metallothioneins. However, it is important to remember that copper is also an essential nutrient for microbial pathogens and serves as important cofactor for enzymes such as cytochrome c oxidase for respiration, superoxide dismutase for anti-oxidant defense and multi-copper oxidases that act on metals and organic substrates. We therefore posit that the animal host can also thwart pathogen growth by limiting their copper nutrients, similar to the well-documented nutritional immunity effects for starving microbes of essential zinc, manganese and iron micronutrients. This review provides both sides of the copper story and evaluates how the host can exploit either copper-the-toxin or copper-the-nutrient in antimicrobial tactics at the host-pathogen battleground.  PMID:26790881

  13. Copper Toxicity in the San Francisco Bay-Delta

    OpenAIRE

    Buck, Kristen N.

    2012-01-01

    San Francisco Bay has high dissolved copper concentrations—relative to nearby coastal waters—that often approach federal water quality standards put in place to protect sensitive marine life. But, how toxic is this copper? Previous studies by other researchers have suggested that metal-binding compounds known as ligands can “grab up” more than 99.9 percent of the total available dissolved copper in seawater, rendering that copper biologically unavailable. Microorganisms that need tra...

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

    Science.gov (United States)

    Rutkowski, E.; Sampson, M. J.

    2015-01-01

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

  15. Comparative effects of dissolved copper and copper oxide nanoparticle exposure to the sea anemone, Exaiptasia pallida

    Energy Technology Data Exchange (ETDEWEB)

    Siddiqui, Samreen; Goddard, Russell H.; Bielmyer-Fraser, Gretchen K., E-mail: gkbielmyer@valdosta.edu

    2015-03-15

    Highlights: • Differences between CuO NP and CuCl{sub 2} exposure were characterized. • Copper accumulation in E. pallida was concentration-dependent. • E. pallida exposed to CuCl{sub 2} accumulated higher copper tissue burdens. • The oxidative stress response was greater in E. pallida exposed to CuO NP. • Both forms of copper inhibited CA activity in E. pallida. - Abstract: Increasing use of metal oxide nanoparticles (NP) by various industries has resulted in substantial output of these NP into aquatic systems. At elevated concentrations, NP may interact with and potentially affect aquatic organisms. Environmental implications of increased NP use are largely unknown, particularly in marine systems. This research investigated and compared the effects of copper oxide (CuO) NP and dissolved copper, as copper chloride (CuCl{sub 2}), on the sea anemone, Exaiptasia pallida. Sea anemones were collected over 21 days and tissue copper accumulation and activities of the enzymes: catalase, glutathione peroxidase, glutathione reductase, and carbonic anhydrase were quantified. The size and shape of CuO NP were observed using a ecanning electron microscope (SEM) and the presence of copper was confirmed by using Oxford energy dispersive spectroscopy systems (EDS/EDX). E. pallida accumulated copper in their tissues in a concentration- and time-dependent manner, with the animals exposed to CuCl{sub 2} accumulating higher tissue copper burdens than those exposed to CuO NP. As a consequence of increased copper exposure, as CuO NP or CuCl{sub 2}, anemones increased activities of all of the antioxidant enzymes measured to some degree, and decreased the activity of carbonic anhydrase. Anemones exposed to CuO NP generally had higher anti-oxidant enzyme activities than those exposed to the same concentrations of CuCl{sub 2}. This study is useful in discerning differences between CuO NP and dissolved copper exposure and the findings have implications for exposure of aquatic

  16. 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

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

    Directory of Open Access Journals (Sweden)

    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.

  18. Point defect relaxation volumes for copper

    International Nuclear Information System (INIS)

    Miller, K.M.

    1979-11-01

    The methods used for the determination of point defect relaxation volumes are discussed and it is shown that a previous interatomic potential derived for copper is inaccurate and results obtained using it are invalid. A new interatomic potential has been produced for copper and a computer simulation of point and planar defects carried out. A vacancy relaxation volume of -0.33 atomic volumes has been found with interstitial values in the range 1.7 to 2.0 atomic volumes. It is shown that these values in current theories of irradiation induced swelling lead to an anomalously high value for dislocation bias compared with that determined experimentally. (author)

  19. Copper Deficiency Myelopathy After Upper Gastrointestinal Surgery.

    Science.gov (United States)

    King, Dominic; Siau, Keith; Senthil, Latha; Kane, Katherine F; Cooper, Sheldon C

    2017-06-01

    A well-functioning alimentary canal is required for adequate nutrient absorption. Disruption to the upper gastrointestinal tract through surgery can lead to micronutrient malnourishment. Copper deficiency has been noted in up to 10% of those undergoing Roux-en-Y gastric bypass surgery, but sequalae are not frequently reported. The resultant deficiency states can have profound and long-term consequences if not realized early and managed appropriately. Here we present a case of copper deficiency myelopathy, a condition indistinguishable from subacute combined degeneration of the spinal cord, following upper gastrointestinal bypass surgery for gastric ulceration, further complicated by inadequate nutrition.

  20. Inhibitory effects of copper on marine dinoflagellates

    Energy Technology Data Exchange (ETDEWEB)

    Saifullah, S.M.

    1978-01-01

    The effect of copper on three species of marine dinoflagellates (Scrippsiella faeroense (Paulsen) Balech et Soares, Prorocentrum micans Ehrenberg, Gymnodinium splendens Lebour) was studied. It inhibited the growth of all species and was lethal to one species in batch cultures. The effect was more pronounced in semicontinuous culture than in batch cultures. Chlorophyll concentrations and rate of uptake of radioactive carbon by cells of S. faeroense were affected in a manner similar to cell numbers. Copper inhibited growth of cells, most probably either by arresting cell division or by penetrating inside the cell and affecting metabolism.

  1. Ductility of Ultra High Purity Copper

    OpenAIRE

    Fujiwara, S.; Abiko, K.

    1995-01-01

    The ductility of ultra-high purity copper at elevated temperatures was investigated : purity 99.9999% (6N) and 99.999999% (8N). Tensile tests were conducted at temperatures ranging from 293K to 1073K at strain rates of 4.2x10-5 s-1 in a high vacuum. The results are discussed in comparison with those for 99.9% (3N) copper. Ductility at intermediate temperatures was improved by an increase in purity. The temperature at which ductility dropped decreased with increases in purity. Even at the ultr...

  2. 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 moisture present, copper content of alloys, type of medium used, and type of bacteria. We examined antibiotic- and copper ion-resistant strains of Escherichia coli and Enterococcus faecium isolated from pig farms following the use of copper sulfate as feed supplement. The results showed rapid killing...... of both copper ion-resistant E. coli and E. faecium strains when samples in rich medium were spread in a thin, moist layer on copper alloys with 85% or greater copper content. E. coli strains were rapidly killed under dry conditions, while E. faecium strains were less affected. Electroplated copper...... surface corrosion rates were determined from electrochemical polarization tests using the Stern-Geary method and revealed decreased corrosion rates with benzotriazole and thermal oxide coating. Copper ion-resistant E. coli and E. faecium cells suspended in 0.8% NaCl showed prolonged survival rates...

  3. Use of flux analysis to study the compartmentation of copper in copper tolerant and non-tolerant Mimulus guttatus

    International Nuclear Information System (INIS)

    Shaw, P.; Collins, J.C.; Thurman, D.A.

    1987-01-01

    Compartmental flux analysis using 64 Cu and a stereological study have been used to estimate the amount and concentrations of copper in the cell wall, cytoplasm and vacuole of roots of non-tolerant and copper tolerant clones of Mimulus guttatus. The cell wall was not found to be a major site of copper accumulation in either clone compared with the cytoplasmic and vacuolar phases. The cytoplasmic concentrations of copper in the non-tolerant clone were significantly grater than those of the tolerant clone when grown in 2.0 and 10.0 μM external copper. At all external copper concentrations and for both clones vacuolar levels of copper were lower than the cytoplasmic ones. At 10.0 μM external copper the vacuolar concentrations of the non-tolerant clone were significantly higher than those of the tolerant clone

  4. Detoxification of copper fungicide using EDTA-modified cellulosic ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-02-04

    Feb 4, 2009 ... detoxification of a copper fungicide (KOCIDE 101) using maize cob, a cellulosic material, was studied. Based on copper as the active agent (after a ... Made from CuSO4 and lime. Used as a spray. Copper oxychloride ..... feasible when there is contact between the maize cob and the Cu(II) ions. Therefore ...

  5. Synthesis of copper telluride nanowires using template-based ...

    Indian Academy of Sciences (India)

    Copper telluride (CuTe) nanowires were synthesized electrochemically from aqueous acidic solution of copper (II) sulphate (CuSO4.5H2O) and tellurium oxide (TeO2) on a copper substrate by template-assisted electrodeposition method. The electrodeposition was conducted at 30 °C and the length of nanowires was ...

  6. Catalytic aspects of a copper (II) complex: biological oxidase to ...

    Indian Academy of Sciences (India)

    This copper complex displays excellent catalytic efficiency, kcat /KM (h⁻¹) = 6.17 × 10⁵ towards the oxidative coupling of 2-aminophenol (2-AP) to aminophenoxazin-3-one. Further, upon stoichiometric addition of copper(II) complex to 3,5-DTBC in presence of molecular oxygen in ethanol medium, the copper complex ...

  7. [Effect of copper deficiency on iron metabolism in rats].

    Science.gov (United States)

    Wang, Kebo; Wang, Chaoxu; Liu, Baosheng; Jiang, Shan

    2010-07-01

    To study the effect of copper deficiency on the nutritional status of iron, the expression of hepcidin mRNA and transferrin receptor mRNA in rats. Forty eight clean male SD rats were randomly divided into four groups according to body weight; and there were 12 rats in each group. The groups are normal iron and copper control group (group I), normal iron and copper deficiency group (group II), normal iron and copper slightly deficient group (group III), both iron and copper slightly deficient group (group IV). Serum, liver and spleen of rats were collected by the end of 8th week. Serum copper, serum iron, hemoglobin, serum transferrin receptor, serum ferritin, liver iron and liver copper, spleen iron and spleen copper were determined. The expression of liver transferring receptor mRNA and hepcidin mRNA were measured by reverse transcription polymerase chain reaction (RT-PCR) method. Compared with the controls, the contents of serum iron and serum ferritin decreased (P copper deficiency. The expression of transferrin receptor mRNA in liver increased but the expression of hepcidin mRNA in liver decreased significantly under copper deficiency (P copper deficiency through influencing the absorption, storage and transportation of iron. Under the condition of copper deficiency, the expression of hepcidin mRNA in liver was lowered and the expression of transferrin receptor mRNA was enhanced through the way of iron response element-iron regulatory protein (IRE-IRP) to regulate iron metabolism.

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

    Science.gov (United States)

    Boutis, Elizabeth; Jantzen, Jonathan Landis, Ed.

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

  9. The determination of copper in biological materials by flame spectrophotometry

    Science.gov (United States)

    Newman, G. E.; Ryan, M.

    1962-01-01

    A method for the determination of the copper content of biological materials by flame spectrophotometry is described. The effects of interference by ions such as sodium and phosphate were eliminated by isolating copper as the dithizonate in CCl4. Results obtained for the urinary excretion of copper by a patient with Wilson's disease before and after treatment with penicillamine are reported. PMID:14479334

  10. Copper-associated hepatitis in dogs; pathogenesis, diagnosis and treatment

    NARCIS (Netherlands)

    Dirksen, K.|info:eu-repo/dai/nl/412424428

    2016-01-01

    Copper is an essential trace element for living organisms, but can have deleterious consequences when present in excess. Because the liver has a central role in copper metabolism, this is the predominant organ affected. Copper-accumulating disorders are recognized as hereditary diseases in man and

  11. Luminescent Colloidal Semiconductor Nanocrystals Containing Copper: Synthesis, Photophysics, and Applications.

    Science.gov (United States)

    Knowles, Kathryn E; Hartstein, Kimberly H; Kilburn, Troy B; Marchioro, Arianna; Nelson, Heidi D; Whitham, Patrick J; Gamelin, Daniel R

    2016-09-28

    Copper-doped semiconductors are classic phosphor materials that have been used in a variety of applications for many decades. Colloidal copper-doped semiconductor nanocrystals have recently attracted a great deal of interest because they combine the solution processability and spectral tunability of colloidal nanocrystals with the unique photoluminescence properties of copper-doped semiconductor phosphors. Although ternary and quaternary semiconductors containing copper, such as CuInS2 and Cu2ZnSnS4, have been studied primarily in the context of their photovoltaic applications, when synthesized as colloidal nanocrystals, these materials have photoluminescence properties that are remarkably similar to those of copper-doped semiconductor nanocrystals. This review focuses on the luminescent properties of colloidal copper-doped, copper-based, and related copper-containing semiconductor nanocrystals. Fundamental investigations into the luminescence of copper-containing colloidal nanocrystals are reviewed in the context of the well-established luminescence mechanisms of bulk copper-doped semiconductors and copper(I) molecular coordination complexes. The use of colloidal copper-containing nanocrystals in applications that take advantage of their luminescent properties, such as bioimaging, solid-state lighting, and luminescent solar concentrators, is also discussed.

  12. Thermal and IR studies on copper doped polyvinyl alcohol

    Indian Academy of Sciences (India)

    TECS

    calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. Increase in glass transition temperature as a function of copper concentration shows a strong branching and steric effects in copper doped PVA com- plexes. Thermal degradation of films to an extent of 4–5% was found with an increase in copper content ...

  13. Structural and magnetic studies on copper succinate dihydrate ...

    Indian Academy of Sciences (India)

    M P BINITHA

    2017-08-21

    Aug 21, 2017 ... Abstract. Single crystals of copper succinate dihydrate were grown in silica gel by slow diffusion of copper chloride to sodium metasilicate gel impregnated with succinic acid. The grown crystal was subjected to single crystal X-ray diffraction studies. In its structure each copper atom is penta co-ordinated to ...

  14. Development of copper bromide laser master oscillator power ...

    Indian Academy of Sciences (India)

    2014-02-09

    Feb 9, 2014 ... Da; 42.60.Jf. 1. Introduction. The copper bromide laser (CBL) is a prominent laser belonging to the class of copper halide lasers [1,2], which are developed to overcome the problems of pure metal copper ... pseudo-Gaussian beam intensity profile that is better suited for many applications than the top-hat ...

  15. Potentiating effect of ecofriendly synthesis of copper oxide ...

    Indian Academy of Sciences (India)

    This study reports the in vitro antimicrobial and anticancer activities of biologically synthesized copper nanoparticles. The antimicrobial activity of green synthesized copper oxide nanoparticles was assessed by well diffusion method. The anticancer activity of brown algae-mediated copper oxide nanoparticles was ...

  16. Synergistic effects of additives to benzotriazole solutions applied as corrosion inhibitors to archaeological copper and copper alloy artefacts.

    OpenAIRE

    Golfomitsou, S.

    2006-01-01

    Benzotriazole (BTA) is a corrosion inhibitor extensively used for the stabilisation of active corrosion of archaeological copper and copper alloys. However, BTA often fails to effectively retard corrosion when applied on heavily corroded artefacts. Although there are numerous studies about its mode of action on clean copper, there is no comprehensive understanding about the way it is bonded to corroded copper. This thesis aimed to understand and compare BTA and its mode of action on clean and...

  17. Broadband Wireline Provider Service: Other Copper Wireline; BBRI_otherCopper12

    Data.gov (United States)

    University of Rhode Island Geospatial Extension Program — This dataset represents the availability of wireline broadband Internet access in Rhode Island via "Other Copper Wireline" technology. In Rhode Island, this category...

  18. Leaching of copper concentrates using NaCl and soluble copper contributed by the own concentrate

    International Nuclear Information System (INIS)

    Herrero, O.; Bernal, N.; Quiroz, R.; Fuentes, G.; Vinals, J.

    2005-01-01

    Leaching of copper concentrates using cupric chloro complexes, generated in situ by the reaction between Cu(II), aported by the soluble copper content of the concentrate, and sodium chloride in acid media was studied. The concentrate samples were obtained from mineral processing plants from Antofagasta, Chile. Chemical and mineralogical characterization from original concentrates was made. Typical variable such as a chloride concentration, soluble copper concentration, leaching time, solid percentage and temperature were studied. DRX and EDS analyzed some of the residues. the experimental results indicated that it is possible to obtain solutions having high copper content (15 to 35 g/L) and 2 to 5 g/L free acid in order to submit this solution directly to a solvent extraction stage. The leaching tests use common reactive and low cost such as sodium chloride and sulfuric acid. (Author) 16 refs

  19. Enrichment of copper and recycling of cyanide from copper-cyanide waste by solvent extraction

    Science.gov (United States)

    Gao, Teng-yue; Liu, Kui-ren; Han, Qing; Xu, Bin-shi

    2016-11-01

    The enrichment of copper from copper-cyanide wastewater by solvent extraction was investigated using a quaternary ammonium salt as an extractant. The influences of important parameters, e.g., organic-phase components, aqueous pH values, temperature, inorganic anion impurities, CN/Cu molar ratio, and stripping reagents, were examined systematically, and the optimal conditions were determined. The results indicated that copper was effectively concentrated from low-concentration solutions using Aliquat 336 and that the extraction efficiency increased linearly with increasing temperature. The aqueous pH value and concentrations of inorganic anion impurities only weakly affected the extraction process when varied in appropriate ranges. The CN/Cu molar ratio affected the extraction efficiency by changing the distribution of copper-cyanide complexes. The difference in gold leaching efficiency between using raffinate and fresh water was negligible.

  20. Bioreduction of Cu(II) by cell-free copper reductase from a copper resistant Pseudomonas sp. NA.

    Science.gov (United States)

    Andreazza, Robson; Okeke, Benedict C; Pieniz, Simone; Brandelli, Adriano; Lambais, Mácio R; Camargo, Flávio A O

    2011-11-01

    Environmental copper contamination is a serious human health problem. Copper reductase is produced by microorganisms to facilitate copper uptake by ATPases into the cells increasing copper biosorption. This study assessed the reduction of Cu(II) by cell-free extracts of a highly copper-resistant bacterium, Pseudomonas sp. strain NA, isolated from vineyard soil contaminated with copper. Both intact cells and cell-free extract of Pseudomonas sp. strain NA displayed substantial reduction of Cu(II). Intact cells reduced more then 80 mg L(-1) of Cu(II) from medium amended with 200 mg L(-1) of copper after 24 h of incubation. Cell-free extract of the isolate reduced more than 65% of the Cu(II) at initial copper concentration of 200 mg L(-1) after 24 h. Soluble protein production was high at 72 h of incubation at 100 mg L(-1) of copper, with more then 60 μg L(-1) of total soluble protein in cell-free extract recorded. Cu(II) reduction by isolate NA was increased when copper concentration increased for both intact cells and cell-free extract. Results indicate that Pseudomonas sp. strain NA produces copper reductase enzyme as the key mechanism of copper biotransformation.

  1. The Hyrkkoelae native copper mineralization as a natural analogue for copper canisters

    Energy Technology Data Exchange (ETDEWEB)

    Marcos, N. [Helsinki Univ. of Technology, Espoo (Finland). Lab. of Engineering Geology and Geophysics

    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{sub 1.934}) after native copper (Cu{sup 0}) under anoxic (reducing) conditions is enhanced by the availability of dissolved HS{sup -} in the groundwater circulating in open fractures in the near-surface zone. The minimum concentration of HS{sup -}in the groundwater is estimated to be of the order of 10{sup -5} M ({approx} 10{sup -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.).

  2. Leach-SX-EW copper revalorization from overburden of abandoned copper mine Cerovo, Eastern Serbia

    Directory of Open Access Journals (Sweden)

    Stevanović Z.

    2009-01-01

    Full Text Available Hydrometallurgical processes for copper revalorization from overburden of abandoned mine Cerovo in Eastern Serbia were studied. Paper contain results of percolation leaching tests, performed with acidic mine waters accumulated in the bottom of the former open pit, followed by solvent extraction (SX and electrowinning (EW processes on achieved copper pregnant leach solutions. Usage of accumulated waste waters was objected to minimizing the environmental hazard due to uncontrolled leaking of these waters in nearby creeks and rivers. Chemical composition of acidic mine waters used for leaching tests was: (g/dm3: Cu - 0.201; Fe - 0.095; Mn - 0.041; Zn - 0.026; Ni - 0.0004; pH value - 3.3. Copper content in overburden sample used for leaching tests was 0.21% from which 64% were oxide copper minerals. In scope of leaching tests were examined influence of leaching solution pH values and iron (III concentration on copper recovery. It was established that for 120 hours of leaching on pH=1.5 without oxidant agents, copper concentration in pregnant leach solutions enriched up to 1.08g/dm3 which was enough for copper extraction from solution with SX-EW treatment. As extraction reagent in SX circuit was used LIX-984N in a kerosene diluent. Cathode current density in electrowinning cell was 220Am-2 while electrolyte temperature was kept on 50±2oC. Produced cathode copper at the end of SX-EW process has purity of 99.95% Cu.

  3. A Study on the Copper Effect on gold leaching in copper-ethanediamine-thiosulphate solutions

    Science.gov (United States)

    Liu, Qiong; Xiang, Pengzhi; Huang, Yao

    2018-01-01

    A simple, fast and sensitive square-wave voltammetry (SWV), cyclic voltammetry(CV) and tafel method for the determination of various factors of gold in thiosulphate solution in this paper. We present our study on the effect of copper(II) on the leaching of gold in thiosulphate solutions. The current study aims to establish the interaction of copper in the leaching process by electrochemical method.

  4. Placenta Copper Transport Proteins in Preeclampsia

    Science.gov (United States)

    Placental insufficiency underlying preeclampsia (PE) is associated with impaired placental angiogenesis. As copper (Cu) is essential to angiogenesis, we investigated differences in the expression of placental Cu transporters Menkes (ATP7A), Wilsons (ATP7B) and the Cu chaperone (CCS) for superoxide d...

  5. Bacterial resistances to mercury and copper.

    Science.gov (United States)

    Brown, N L; Camakaris, J; Lee, B T; Williams, T; Morby, A P; Parkhill, J; Rouch, D A

    1991-06-01

    Heavy metals are toxic to living organisms. Some have no known beneficial biological function, while others have essential roles in physiological reactions. Mechanisms which deal with heavy metal stress must protect against the deleterious effects of heavy metals, yet avoid depleting the cell of a heavy metal which is also an essential nutrient. We describe the mechanisms of resistance in Escherichia coli to two different heavy metals, mercury and copper. Resistance of E. coli to mercury is reasonably well understood and is known to occur by transport of mercuric ions into the cytoplasmic compartment of the bacterial cell and subsequent reductive detoxification of mercuric ions. Recent mutational analysis has started to uncover the mechanistic detail of the mercuric ion transport processes, and has shown the essential nature of cysteine residues in transport of Hg(II). Resistance to copper is much less well understood, but is known to involve the increased export of copper from the bacterial cell and modification of the copper; the details of the process are still being elucidated. Expression of both metal resistance determinants is regulated by the corresponding cation. In each case the response enables the maintenance of cellular homeostasis for the metal. The conclusions drawn allow us to make testable predictions about the regulation of expression of resistance to other heavy metals.

  6. Copper-Tungsten Composites Sprayed by HVOF

    Czech Academy of Sciences Publication Activity Database

    Matějíček, Jiří; Zahálka, F.; Bensch, Jan; Chi, W.; Sedláček, J.

    2008-01-01

    Roč. 17, č. 2 (2008), s. 177-180 ISSN 1059-9630 Institutional research plan: CEZ:AV0Z20430508 Keywords : Thermally sprayed coatings * tungsten * copper * HVOF Subject RIV: JG - Metallurgy Impact factor: 1.200, year: 2008 http://www.springerlink.com/content/120439/

  7. Electron impact single ionization of copper

    Indian Academy of Sciences (India)

    Electron impact single ionization cross sections of copper have been calculated in the binary encounter approximation using accurate expression for as given by Vriens and Hartree–Fock momentum distribution for the target electron. The BEA calculation based on the usual procedure does not show satisfactory ...

  8. Synthesis and optical characterization of copper nanoparticles ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 40; Issue 1. Synthesis and optical characterization of copper nanoparticles prepared by laser ablation. SAMIRA MONIRI MAHMOOD GHORANNEVISS MOHAMMAD REZA HANTEHZADEH MOHSEN ASADI ASADABAD. Volume 40 Issue 1 February 2017 pp 37-43 ...

  9. Properties of Chemically Synthesized Nanostructured Copper (II ...

    African Journals Online (AJOL)

    Wet chemical method has been successfully used in preparation of Copper (II) Oxide Thin Film by spin coating on glass substrates, at an annealing temperature of 600°C for 1 hour in air. It has high absorbency within visible region wavelength 400 – 700 nm of the electromagnetic wave, making it a suitable absorber in the ...

  10. Copper Doped Wavequides in Glass Substrates

    Czech Academy of Sciences Publication Activity Database

    Špirková, J.; Nebolová, P.; Jirka, Ivan; Mach, Karel; Peřina, Vratislav; Macková, Anna; Kuncová, Gabriela

    2002-01-01

    Roč. 21, č. 1 (2002), s. 63-74 ISSN 0146-8030 R&D Projects: GA ČR GA102/99/1391; GA ČR GA102/99/0549 Institutional research plan: CEZ:AV0Z4040901 Keywords : wavequides * refractive index * copper Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 0.535, year: 2002

  11. Discontinuous precipitation in copper base alloys

    Indian Academy of Sciences (India)

    Discontinuous precipitation (DP) is associated with grain boundary migration in the wake of which alternate plates of the precipitate and the depleted matrix form. Some copper base alloys show ... 100 > ± 0.1, DP is observed. This criterion points to diffusional coherency strain theory to be the operative mechanism for DP.

  12. Fatigue mechanisms in ultrafine-grained copper

    Czech Academy of Sciences Publication Activity Database

    Lukáš, Petr; Kunz, Ludvík; Svoboda, Milan

    2009-01-01

    Roč. 47, č. 1 (2009), s. 1-9 ISSN 0023-432X R&D Projects: GA AV ČR(CZ) 1QS200410502 Institutional research plan: CEZ:AV0Z20410507 Keywords : ultrafine-grained copper * effect of purity * effect of temperature Subject RIV: JL - Materials Fatigue, Friction Mechanics Impact factor: 1.345, year: 2007

  13. Iron, ferritin and copper in seminal plasma.

    Science.gov (United States)

    Kwenang, A; Kroos, M J; Koster, J F; van Eijk, H G

    1987-07-01

    The levels of iron, copper and ferritin were measured in seminal plasma from young healthy students and infertile men with severe teratospermia. No significant differences were found between them. The iron might be available for lipid peroxidation unless it is bound in some way. The role of ferritin in O2- formation is discussed.

  14. Fluidized bed electrowinning of copper. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-01

    The objectives of the study were to: design and construct a 10,000- amp fluidized bed electrowinning cell for the recovery of copper from acidic sulfate solutions; demonstrate the technical feasibility of continuous particle recirculation from the electrowinning cell with the ultimate goal of continuous particle removal; and measure cell efficiency as a function of operating conditions.

  15. Material characterization of ancient Indian copper

    Indian Academy of Sciences (India)

    Unknown

    iron technology and possessed a different material cul- ture. The reoccupation of the site suggests its ..... where chloride ions are excluded, as in the present study, microstructural investigations on archaeological ... copper extraction and application remained almost simi- lar for a large period in Indian history based on the.

  16. CopperCore 2.2

    NARCIS (Netherlands)

    Martens, Harrie; Vogten, Hubert; Koper, Rob

    2005-01-01

    Changes in this release: repackaged the source code classes, split coppercore archive packages in smaller packages, added a coppercore.ear archive for easy deployment of CopperCore on the application server, updated the build scripts for accommodating these changes, fixed some bugs.

  17. CopperCore 2.2.3

    NARCIS (Netherlands)

    Vogten, Hubert; Martens, Harrie; Koper, Rob

    2005-01-01

    Changes in this version: great number of bug fixes with regard to notifcation handling, allowed empty items in order to be more compatible with Reload, added QTI content type for CopperCore Service Integration, improved error handling, improved Clicc and fixed a bug regarding the else operation in a

  18. An externally heated copper vapour laser

    International Nuclear Information System (INIS)

    Rochefort, P.A.; Sopchyshyn, F.C.; Selkirk, E.B.; Green, L.W.

    1993-08-01

    A pulsed Copper Vapour Laser (CVL), with a nominal 6 kHz repetition rate, was designed, build, and commissioned at Chalk River laboratories. The laser was required for Resonant Ionization Mass Spectroscopy (RIMS) experiments and for projects associated with Atomic Vapour laser Isotope Separation (AVLIS) studies. For the laser to operate, copper coupons position along the length of a ceramic tube must be heated sufficiently to create an appropriate vapour pressure. The AECL CVL uses an external heater element with a unique design to raise the temperature of the tube. The Cylindrical graphite heating element is shaped to compensate for the large radiation end losses of the laser tube. The use of an external heater saves the expensive high-current-voltage switching device from heating the laser tube, as in most commercial lasers. This feature is especially important given the intermittent usage typical of experimental research. As well, the heater enables better parametric control of the laser output when studying the lasing of copper (or other) vapour. This report outlines the lasing process in copper vapour, describes in detail all three major laser sub-systems: the laser body; the laser tube heater; the high voltage pulsed discharge; and, reports parametric measurements of the individual sub-systems and the laser system as a whole. Also included are normal operating procedures to heat up, run and shut down the laser

  19. EFFECT OF COPPER ON PASSIVITY AND CORROSION ...

    African Journals Online (AJOL)

    2014-06-30

    Jun 30, 2014 ... alloys. Corrosion parameters in H2SO4 1N solution have been established by carrying out electrochemical studies such as potentiodynamic (Tafel polarization and linear polarization,. LP) and electrochemical impedance spectroscopy (EIS). The coupled effect copper/microstructure is discussed. Alloying ...

  20. Art of Wrought Copper in Turkey

    Directory of Open Access Journals (Sweden)

    Nuran KAYABAŞI

    2014-07-01

    Full Text Available Among the handicraft, art of being a coppersmith has been occurred intensively in the past. The fast developing socio - economic structure diminished the value and the place of the copper vessels. Heavy and beautiful vessels made by beating left their places to thin, light aluminum, pl astic, glass and steel vessels made by machinery. The demand for copper is diminished. Therefore being a coppersmith has become less and less important every day. However, in the last few years, copper vessels becoming a touristic souvenir became a source of hope for the traditional coppersmith art to live on. Copperworking is applied in our country in some regions and there are people who live off it. Souvenirs, daily used vessels, and requirements of the rural areas are produced in centers such as İstanb ul, Ankara, Tokat, Çorum, Erzincan, Diyarbakır, Kahramanmaraş, Gaziantep, Bursa, Kastamonu, Çankırı, Giresun and Trabzon. The situation of being a coppersmith in Turkey is explained, examples are given from souvenir copper items produced in Ankara, and sug gestions are made to keep this craft alive.

  1. Spectrophotometric determination of copper with ascorbic acid

    International Nuclear Information System (INIS)

    Majeed, A.; Mustafa, M.M.; Asma, R.N.; Sareecha, N.

    1996-01-01

    Copper has been determined spectrophotometrically by using ascorbic acid as a chromagenic reagent. The complex formed in basic medium is measured for its absorbance at 340 n.m. Interference for 23 cations and 9 anions has also been checked. Effect of pH, time, temperature, ammonia, reagent concentration and interferents has been report. (author)

  2. Alternative Anode Reaction for Copper Electrowinning

    Energy Technology Data Exchange (ETDEWEB)

    2005-07-01

    This report describes a project funded by the Department of Energy, with additional funding from Bechtel National, to develop a copper electrowinning process with lower costs and lower emissions than the current process. This new process also includes more energy efficient production by using catalytic-surfaced anodes and a different electrochemical couple in the electrolyte, providing an alternative oxidation reaction that requires up to 50% less energy than is currently required to electrowin the same quantity of copper. This alternative anode reaction, which oxidizes ferric ions to ferrous, with subsequent reduction back to ferric using sulfur dioxide, was demonstrated to be technically and operationally feasible. However, pure sulfur dioxide was determined to be prohibitively expensive and use of a sulfur burner, producing 12% SO{sub 2}, was deemed a viable alternative. This alternate, sulfur-burning process requires a sulfur burner, waste heat boiler, quench tower, and reaction towers. The electrolyte containing absorbed SO{sub 2} passes through activated carbon to regenerate the ferrous ion. Because this reaction produces sulfuric acid, excess acid removal by ion exchange is necessary and produces a low concentration acid suitable for leaching oxide copper minerals. If sulfide minerals are to be leached or the acid unneeded on site, hydrogen was demonstrated to be a potential reductant. Preliminary economics indicate that the process would only be viable if significant credits could be realized for electrical power produced by the sulfur burner and for acid if used for leaching of oxidized copper minerals on site.

  3. Photocleavage of DNA by copper (II) complexes

    Indian Academy of Sciences (India)

    The mechanistic pathways are found to be dependent on the types of ligands present in the copper(II) complexes and the photo-excitation energy. While UV exposure generally proceeds via a type-II process forming singlet oxygen as the reactive species, red-light exposure leads to DNA cleavage following different ...

  4. Plasma Copper Status in Hypercholesterolemic Patients

    African Journals Online (AJOL)

    Dr Femi Olaleye

    reduced during early stages of copper deficiency in rats. J. Nutr. 124, 628-635. Anon (2000): Cardiovascular disease ranks as the first cause of death in Spain. Rev Esp Salud Publica 74 (3),. 215-53. Anon. (1967): Vital Statistics of the United States. Mortality, Washington: U.S. Dept. Health, Educ. Wefare, 1969, vol. 2, Part A ...

  5. Synthesis of Nanocrystalline Cellulose Stabilized Copper Nanoparticles

    Directory of Open Access Journals (Sweden)

    Aminu Musa

    2016-01-01

    Full Text Available A chemical reduction method was employed for the synthesis of copper nanoparticles stabilized by nanocrystalline cellulose (NCC using different concentrations of copper salt in aqueous solution under atmospheric air. CuSO4·5H2O salt and hydrazine were used as metal ion precursor and reducing agent, respectively. Ascorbic acid and aqueous NaOH were also used as an antioxidant and a pH moderator, respectively. The number of CuNPs increased with increasing concentration of the precursor salt. The formation of copper nanoparticles stabilized by NCC (CuNPs@NCC was investigated by UV-visible spectroscopy (UV-vis, where the surface absorption maximum was observed at 590 nm. X-ray diffraction (XRD analysis showed that the CuNPs@NCC are of a face-centered cubic structure. Moreover, the morphology of the CuNPs@NCC was investigated using transmission electron microscope (TEM and field emission scanning electron microscope (FESEM, which showed well-dispersed CuNPs with an average particle size less than 4 nm and the shape of CuNPs was found to be spherical. Energy dispersive X-ray spectroscope (EDS also confirmed the presence of CuNPs on the NCC. The results demonstrate that the stability of CuNPs decreases with an increasing concentration of the copper ions.

  6. Copper transporters and chaperones: Their function on ...

    Indian Academy of Sciences (India)

    2016-08-02

    Aug 2, 2016 ... to be as high as 1500 μg/g dry weight, causing severe morphological and functional changes which include ... Loss of ATP7B activity leads to accumulation of intracellular copper, which in turn leads to increase ... Initially it was reported that neither Cu starvation followed by Cu exposure nor an increase in ...

  7. Reactions of copper (II) in electrospray

    Czech Academy of Sciences Publication Activity Database

    Jaklová Dytrtová, Jana; Jakl, M.; Kašička, Václav

    2017-01-01

    Roč. 13, č. 1 (2017), s. 83 ISSN 1336-7242. [69. Zjazd chemikov. 11.09.2017-15.09.2017, Horný Smokovec] Institutional support: RVO:61388963 Keywords : copper (II) * electrospray * organic ligand Subject RIV: CB - Analytical Chemistry, Separation

  8. Dislocation Microstructures in Fatiqued Copper Polycrystals

    DEFF Research Database (Denmark)

    Winter, A.T.; Pedersen, Ole Bøcker; Rasmussen, K.V.

    1981-01-01

    Dislocation structures characteristic of persistent slip bands were observed in the interior of polycrystalline copper after fatigue. At low strain amplitudes, within the plateau on the cyclic stress-strain curve, only structures identical to those seen in single crystals were observed. This allows...

  9. Revealing the Maximum Strength in Nanotwinned Copper

    DEFF Research Database (Denmark)

    Lu, L.; Chen, X.; Huang, Xiaoxu

    2009-01-01

    boundary–related processes. We investigated the maximum strength of nanotwinned copper samples with different twin thicknesses. We found that the strength increases with decreasing twin thickness, reaching a maximum at 15 nanometers, followed by a softening at smaller values that is accompanied by enhanced...

  10. Copper(II) complexes with aroylhydrazones

    Indian Academy of Sciences (India)

    The coordination chemistry of copper(II) with tridentate aroylhydrazones is briefly discussed in this article. Two types of aroylhydrazones derived from aroylhydrazines and ortho-hydroxy aldehydes or 2-pyridine-carboxaldehyde have been used. The characterization of the complexes has been performed with the help of ...

  11. Microwave attenuation with composite of copper microwires

    International Nuclear Information System (INIS)

    Gorriti, A.G.; Marin, P.; Cortina, D.; Hernando, A.

    2010-01-01

    It is shown that copper microwires composite media attenuates microwave reflection of metallic surfaces. We show how the distance to the metallic surface, as well as the length and volume fraction of microwires, determine the frequency of maximum absorption and the return loss level. Furthermore, we were able to fit the experimental results with a theoretical model based on Maxwell-Garnett mixing formula.

  12. Microwave attenuation with composite of copper microwires

    Energy Technology Data Exchange (ETDEWEB)

    Gorriti, A.G.; Marin, P. [Instituto de Magnetismo Aplicado, (UCM-ADIF-CSIC) and Departamento de Fisica de Materiales (UCM). P.O. Box 155, Las Rozas, Madrid 28230 (Spain); Cortina, D. [Micromag S.L., Las Rozas, Madrid 28230 (Spain); Hernando, A., E-mail: antonio.hernando@adif.e [Instituto de Magnetismo Aplicado, (UCM-ADIF-CSIC) and Departamento de Fisica de Materiales (UCM). P.O. Box 155, Las Rozas, Madrid 28230 (Spain); Micromag S.L., Las Rozas, Madrid 28230 (Spain)

    2010-05-15

    It is shown that copper microwires composite media attenuates microwave reflection of metallic surfaces. We show how the distance to the metallic surface, as well as the length and volume fraction of microwires, determine the frequency of maximum absorption and the return loss level. Furthermore, we were able to fit the experimental results with a theoretical model based on Maxwell-Garnett mixing formula.

  13. CopperCore 3.2

    NARCIS (Netherlands)

    Martens, Harrie; Vogten, Hubert

    2008-01-01

    Available under the GNU GPL license. CopperCore version 3.2 release notes (2008-11-14) ================================================= 2008-05-09 FIXED: changed all references to PropertyLookUp to PropertyLookup in the SQL statements. Caused problems with MySQL in Linux 2008-03-19 CHNGD: added the

  14. Synthesis and optical characterization of copper nanoparticles ...

    Indian Academy of Sciences (India)

    cer treatment, photonics, information technology, materials science, etc. [4]. From a general point of view, Cu NPs are finding many usages in nanocircuits, nanoelectronics, nanodevices, plas- monic, optics, nanosensors, etc. [5,6]. In particular, copper NPs possess photo-sensitivity and electrical conductivity, which makes ...

  15. Prospects of Colloidal Copper Chalcogenide Nanocrystals

    NARCIS (Netherlands)

    van der Stam, W.; Berends, A.C.; de Mello-Donega, Celso

    2016-01-01

    Over the past few years, colloidal copper chalcogenide nanocrystals (NCs) have emerged as promising alternatives to conventional Cd and Pb chalcogenide NCs. Owing to their wide size, shape, and composition tunability, Cu chalcogenide NCs hold great promise for several applications, such as

  16. CopperCore 3.1

    NARCIS (Netherlands)

    Vogten, Hubert; Martens, Harrie

    2008-01-01

    CopperCore version 3.1 release notes (2006-20-09) ================================================= 2007-27-03 ADDED: added support for MySQL 2006-12-12 FIXED: referencing to a global personal property from within the unit of earning defining it caused a class cast execption. 2006-12-05 FIXED:

  17. Discontinuous precipitation in copper base alloys

    Indian Academy of Sciences (India)

    Discontinuous precipitation (DP) is associated with grain boundary migration in the wake of which alternate plates of the precipitate and the depleted matrix form. Some copper base alloys show DP while others do not. In this paper the misfit strain parameter, , has been calculated and predicted that if 100 > ± 0.1, DP is ...

  18. Material characterization of ancient Indian copper

    Indian Academy of Sciences (India)

    Unknown

    Department of Materials and Metallurgical Engineering, Indian Institute of Technology, Kanpur 208 016, India. MS received 15 April 2003; revised 7 July 2003. Abstract. A chalcolithic (2350–1800 BC) copper chisel from Balathal has been characterized by X-ray diffraction, microstructural and electrochemical methods.

  19. On the "stacking fault" in copper

    NARCIS (Netherlands)

    Fransens, J.R.; Pleiter, F

    2003-01-01

    The results of a perturbed gamma-gamma angular correlations experiment on In-111 implanted into a properly cut single crystal of copper show that the defect known in the literature as "stacking fault" is not a planar faulted loop but a stacking fault tetrahedron with a size of 10-50 Angstrom.

  20. Preparation and characterization of nanostructured copper bismuth ...

    Indian Academy of Sciences (India)

    Thin films of copper bismuth diselenide were prepared by chemical bath deposition technique onto glass substrate below 60°C. The deposition parameters such as time, temperature of deposition and pH of the solution, were optimized. The set of films having different elemental compositions was prepared by varying Cu/Bi ...

  1. Unleaded shooting: hunters like copper bullets

    African Journals Online (AJOL)

    2007-03-01

    Mar 1, 2007 ... Ammunition, Bismuth Cartridge Co. and Barnes Bullets to let hunters see if they worked. They did. Shot groups fired with the Barnes copper hollow point. Triple Shock X-Bullet were generally tighter than with conventional softpoint bullets. A test firing of the two types of bullets into plastic bins filled with wet.

  2. Characteristics and antimicrobial activity of copper-based materials

    Science.gov (United States)

    Li, Bowen

    In this study, copper vermiculite was synthesized, and the characteristics, antimicrobial effects, and chemical stability of copper vermiculite were investigated. Two types of copper vermiculite materials, micron-sized copper vermiculite (MCV) and exfoliated copper vermiculite (MECV), are selected for this research. Since most of the functional fillers used in industry products, such as plastics, paints, rubbers, papers, and textiles prefer micron-scaled particles, micron-sized copper vermiculite was prepared by jet-milling vermiculite. Meanwhile, since the exfoliated vermiculite has very unique properties, such as high porosity, specific surface area, high aspect ratio of laminates, and low density, and has been extensively utilized as a functional additives, exfoliated copper vermiculite also was synthesized and investigated. The antibacterial efficiency of copper vermiculite was qualitatively evaluated by the diffusion methods (both liquid diffusion and solid diffusion) against the most common pathogenic species: Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Klebsiella pneumoniae (K. pneumoniae). The result showed that the release velocity of copper from copper vermiculite is very slow. However, copper vermiculite clearly has excellent antibacterial efficiency to S. aureus, K. pneumoniae and E. coli. The strongest antibacterial ability of copper vermiculite is its action on S. aureus. The antibacterial efficiency of copper vermiculite was also quantitatively evaluated by determining the reduction rate (death rate) of E. coli versus various levels of copper vermiculite. 10 ppm of copper vermiculite in solution is sufficient to reduce the cell population of E. coli, while the untreated vermiculite had no antibacterial activity. The slow release of copper revealed that the antimicrobial effect of copper vermiculite was due to the strong interactions between copper ions and bacteria cells. Exfoliated copper vermiculite has even stronger

  3. Some aspects of copper metabolism in Brindled mice

    International Nuclear Information System (INIS)

    Prins, H.W.

    1981-01-01

    The semi-dominant X-linked mutation in Brindled mice causes a severe copper deficiency of which the hemizygous Brindled mice die between 14 and 21 days post partum. Previously, in analogy to Menkes' disease in man, the primary defect in mutated Brindled mice has been described as a block in the resorption of alimentary copper, i.e., the transport of copper from the intestinal lumen into the portal blood circulation. During this research it became clear that the impaired resorption of alimentary copper is only a part of a more general aberration of copper metabolism in epithelioid cells. Tracer techniques using 64 Cu are used for metabolism studies. (Auth.)

  4. Simultaneous Platinum and Copper Ion Attachment to a Human Copper Chaperone Protein

    Science.gov (United States)

    Hodak, Miroslav; Cvitkovic, John; Yu, Corey; Dmitriev, Oleg; Kaminski, George; Bernholc, Jerry

    2015-03-01

    Cisplatin is a potent anti-cancer drug based on a platinum ion. However, its effectiveness is decreased by cellular resistance, which involves cisplatin attaching to copper transport proteins. One of such proteins is Atox1, where cisplatin attaches to the copper binding site. Surprisingly, it was shown that both cisplatin and copper can attach to Atox1 at the same time. To study this double metal ion attachment, we use the KS/FD DFT method, which combines Kohn-Sham DFT with frozen-density DFT to achieve efficient quantum-mechanical description of explicit solvent. Calculations have so far investigated copper ion attachment to CXXC motifs present in Atox1. The addition of the platinum ion and the competition between the two metals is currently being studied. These calculations start from a molecular mechanics (MM) structural model, in which glutathione groups provide additional ligands to the Pt ion. Our goals are to identify possible Cu-Pt structures and to determine whether copper/platinum attachment is competitive, independent, or cooperative. Results will be compared to the 1H, N1 5 -HSQC NMR experiments, in which binding of copper and cisplatin to Atox1 produces distinct secondary chemical shift signatures, allowing for kinetic studies of simultaneous metal binding.

  5. Fabrication of Elemental Copper by Intense Pulsed Light Processing of a Copper Nitrate Hydroxide Ink.

    Science.gov (United States)

    Draper, Gabriel L; Dharmadasa, Ruvini; Staats, Meghan E; Lavery, Brandon W; Druffel, Thad

    2015-08-05

    Printed electronics and renewable energy technologies have shown a growing demand for scalable copper and copper precursor inks. An alternative copper precursor ink of copper nitrate hydroxide, Cu2(OH)3NO3, was aqueously synthesized under ambient conditions with copper nitrate and potassium hydroxide reagents. Films were deposited by screen-printing and subsequently processed with intense pulsed light. The Cu2(OH)3NO3 quickly transformed in less than 100 s using 40 (2 ms, 12.8 J cm(-2)) pulses into CuO. At higher energy densities, the sintering improved the bulk film quality. The direct formation of Cu from the Cu2(OH)3NO3 requires a reducing agent; therefore, fructose and glucose were added to the inks. Rather than oxidizing, the thermal decomposition of the sugars led to a reducing environment and direct conversion of the films into elemental copper. The chemical and physical transformations were studied with XRD, SEM, FTIR and UV-vis.

  6. Formation of copper gasars at subatmospheric pressures

    Science.gov (United States)

    Rau, Helen J.

    Gasars are directionally porous materials formed by the solidification of a gas-saturated melt. The pores are formed due to the change in gas solubility upon solidification of the melt. The porosity and pore size formed are affected by the direction and rate of solidification, soluble and inert gas partial pressures, and melt temperature. Gasars can be formed in many systems, including aluminum-hydrogen, copper-hydrogen, iron-nitrogen, magnesium-hydrogen, and nickel-hydrogen systems. Studies on gasar formation are largely qualitative, containing few if any sample replicates, and often lack quantification of key processing variables (such as solidification rate). This work was undertaken in an attempt to better understand the basic formation of gasars using the copper-hydrogen system at subatmospheric gas pressures (less than 91.2 kPa/0.9 atm). Samples were made using electrolytic copper which was saturated with hydrogen gas and tilt poured onto a water-cooled copper chill (in order to directionally solidify). For each set of processing conditions, three samples were cast. Solidification rate, porosity, pore size, and inter-pore spacing were measured for the samples. The solidification rate ranged from 1.0 to 4.1 mm/s depending on the sample diameter. Porosity was found to decrease with increasing solidification rate and experimental results and predicted porosities were in better agreement for samples with higher total applied pressure. Pore size was found to increase with decreasing solidification velocity, and the total applied pressure had the greatest effect on the pore size (with decreased pressure resulting in larger pores). Pore size distribution was found to be bimodal. Inter-pore spacing was found to increase with decreasing solidification rate and total applied pressure. Results were analyzed and compared with existing models (some of which were modified for use with the copper-hydrogen system) and comments on the effectiveness of the models are provided.

  7. [Effects of copper deficiency on iron metabolism in rats].

    Science.gov (United States)

    Xiao, Fei; Wang, Chaoxu; Yang, Li

    2013-07-01

    To study the effects of copper deficiency on iron metabolism, the expression of IRP mRNA and Fn mRNA and transferrin receptor mRNA in rats. Forty clean male SD rats were randomly divided into four groups according to body weight and there were 10 rats in each group. The groups are normal iron and copper control group (group I), copper deficiency group (group II), normal iron and copper slightly deficient group (group III), both iron and copper slightly deficient group (group IV). After 8 weeks, all the rats were killed by sodium pentobarbital anesthesia and all samples were collected and detected for gene expression. Compared with the controls, the contents of serum iron and serum ferritin in completely copper deficiency group decreased (P copper deficiency (P copper deficiency group was significantly increased (P copper deficiency group was significantly decreased (P copper deficiency through influencing the absorption, the results indicate that copper deficiency influences iron homeostasis in cells through affecting the expression of IRP2 and the activity of IRP-RNA combination which change the expressions of ferritin and transferrin mRNA.

  8. Zinc stress induces copper depletion in Acinetobacter baumannii.

    Science.gov (United States)

    Hassan, Karl A; Pederick, Victoria G; Elbourne, Liam D H; Paulsen, Ian T; Paton, James C; McDevitt, Christopher A; Eijkelkamp, Bart A

    2017-03-11

    The first row transition metal ions zinc and copper are essential to the survival of many organisms, although in excess these ions are associated with significant toxicity. Here, we examined the impact of zinc and copper stress on Acinetobacter baumannii, a common opportunistic pathogen. We show that extracellular zinc stress induces a copper-specific depletion phenotype in A. baumannii ATCC 17978. Supplementation with copper not only fails to rescue this phenotype, but further exacerbates the copper depletion. Extensive analysis of the A. baumannii ATCC 17978 genome identified 13 putative zinc/copper resistance efflux pumps. Transcriptional analyses show that four of these transporters are responsive to zinc stress, five to copper stress and seven to the combination of zinc and copper stress, thereby revealing a likely foundation for the zinc-induced copper starvation in A. baumannii. In addition, we show that zinc and copper play crucial roles in management of oxidative stress and the membrane composition of A. baumannii. Further, we reveal that zinc and copper play distinct roles in macrophage-mediated killing of this pathogen. Collectively, this study supports the targeting of metal ion homeostatic mechanisms as an effective antimicrobial strategy against multi-drug resistant bacterial pathogens.

  9. Cement mixtures containing copper tailings as an additive: durability properties

    Directory of Open Access Journals (Sweden)

    Obinna Onuaguluchi

    2012-12-01

    Full Text Available The effects of copper tailings as an additive, on some durability properties of cement mixtures were investigated. In each mixture, copper tailings addition levels by mass were 0%, 5% and 10%. Compared to the control samples, copper tailings blended pastes showed superior performance against autoclave expansion while insignificant decreases in sulfate resistance of mortars were observed. Copper tailings increased the water absorption and total permeable voids of concretes slightly. However, the compressive and flexural strengths of blended concretes were higher than those of the control samples. Similarly, improved resistance to acid attack and chloride penetration as the copper tailings content of concretes increased were also observed. Results further showed that the ASTM C 1202 rapid chloride permeability test may not be a valid indicator of chloride migration in mixtures containing conductive copper tailings. These results suggest that copper tailings can potentially enhance the durability properties of cement based materials.

  10. Case of sensory ataxic ganglionopathy-myelopathy in copper deficiency.

    Science.gov (United States)

    Zara, Gabriella; Grassivaro, Francesca; Brocadello, Filippo; Manara, Renzo; Pesenti, Francesco Francini

    2009-02-15

    Spinal cord involvement associated with severe copper deficiency has been reported in the last 8 years. Copper deficiency may produce an ataxic myelopathy. Clinical and neuroimaging findings are similar to the subacute combined degeneration seen in patients with vitamin B12 deficiency. Macrocytic, normocytic and microcytic anemia, leukopenia and, in severe cases, pancytopenia are well known hematologic manifestations. The most patients with copper deficiency myelopathy had unrecognized carency. Some authors suggested that early recognition and copper supplementation may prevent neurologic deterioration but clinical findings do not improve. We present a patient with copper deficiency, dorsal root ganglions and cervical dorsal columns involvement. Clinical status and neuroimaging improved after copper replacement therapy. Sensory neurons of dorsal root ganglia may be the most sensitive nervous pathway. In this case the early copper treatment allowed to improve neurologic lesions and to prevent further involvements.

  11. Electrodialytic remediation of copper mine tailings: Comparing different operational conditions

    DEFF Research Database (Denmark)

    Rojo, Adrian; Hansen, Henrik K.; Ottosen, Lisbeth M.

    2006-01-01

    This work compares and evaluates sixteen electrodialytic laboratory remediation experiments on copper mine tailings. Different parameters were analyzed, such as remediation time, voltage drop, addition of desorbing agents, and the use of pulsed electrical fields. The results show that electric...... of copper citrate complexes. Using pulsed electric fields the remediation process with sulphuric acid addition was also improved by a decrease in the polarization cell. Main results: considering remediation with watery tailing as the base line, for three weeks experiments no copper removal was observed......, adding sulphuric acid total copper removal reached 39%. Adding citric acid, total copper removal was improved in terms of remediation time: after 5h experiment copper removal was 16% instead of 9% obtained after 72h with sulphuric acid addition. Using pulsed electric fields total copper removal was also...

  12. Copper imbalances in ruminants and humans: unexpected common ground.

    Science.gov (United States)

    Suttle, Neville F

    2012-09-01

    Ruminants are more vulnerable to copper deficiency than humans because rumen sulfide generation lowers copper availability from forage, increasing the risk of conditions such as swayback in lambs. Molybdenum-rich pastures promote thiomolybdate (TM) synthesis and formation of unabsorbable Cu-TM complexes, turning risk to clinical reality (hypocuprosis). Selection pressures created ruminant species with tolerance of deficiency but vulnerability to copper toxicity in alien environments, such as specific pathogen-free units. By contrast, cases of copper imbalance in humans seemed confined to rare genetic aberrations of copper metabolism. Recent descriptions of human swayback and the exploratory use of TM for the treatment of Wilson's disease, tumor growth, inflammatory diseases, and Alzheimer's disease have created unexpected common ground. The incidence of pre-hemolytic copper poisoning in specific pathogen-free lambs was reduced by an infection with Mycobacterium avium that left them more responsive to treatment with TM but vulnerable to long-term copper depletion. Copper requirements in ruminants and humans may need an extra allowance for the "copper cost" of immunity to infection. Residual cuproenzyme inhibition in TM-treated lambs and anomalies in plasma copper composition that appeared to depend on liver copper status raise this question "can chelating capacity be harnessed without inducing copper-deficiency in ruminants or humans?" A model of equilibria between exogenous (TM) and endogenous chelators (e.g., albumin, metallothionein) is used to predict risk of exposure and hypocuprosis; although risk of natural exposure in humans is remote, vulnerability to TM-induced copper deficiency may be high. Biomarkers of TM impact are needed, and copper chaperones for inhibited cuproenzymes are prime candidates.

  13. Copper Imbalances in Ruminants and Humans: Unexpected Common Ground1

    Science.gov (United States)

    Suttle, Neville F.

    2012-01-01

    Ruminants are more vulnerable to copper deficiency than humans because rumen sulfide generation lowers copper availability from forage, increasing the risk of conditions such as swayback in lambs. Molybdenum-rich pastures promote thiomolybdate (TM) synthesis and formation of unabsorbable Cu-TM complexes, turning risk to clinical reality (hypocuprosis). Selection pressures created ruminant species with tolerance of deficiency but vulnerability to copper toxicity in alien environments, such as specific pathogen–free units. By contrast, cases of copper imbalance in humans seemed confined to rare genetic aberrations of copper metabolism. Recent descriptions of human swayback and the exploratory use of TM for the treatment of Wilson’s disease, tumor growth, inflammatory diseases, and Alzheimer’s disease have created unexpected common ground. The incidence of pre–hemolytic copper poisoning in specific pathogen–free lambs was reduced by an infection with Mycobacterium avium that left them more responsive to treatment with TM but vulnerable to long-term copper depletion. Copper requirements in ruminants and humans may need an extra allowance for the “copper cost” of immunity to infection. Residual cuproenzyme inhibition in TM-treated lambs and anomalies in plasma copper composition that appeared to depend on liver copper status raise this question “can chelating capacity be harnessed without inducing copper-deficiency in ruminants or humans?” A model of equilibria between exogenous (TM) and endogenous chelators (e.g., albumin, metallothionein) is used to predict risk of exposure and hypocuprosis; although risk of natural exposure in humans is remote, vulnerability to TM-induced copper deficiency may be high. Biomarkers of TM impact are needed, and copper chaperones for inhibited cuproenzymes are prime candidates. PMID:22983845

  14. Tolerance of Oocystis nephrocytioides to copper: intracellular distribution and extracellular complexation of copper

    International Nuclear Information System (INIS)

    Soldo, Diana; Hari, Renata; Sigg, Laura; Behra, Renata

    2005-01-01

    Several mechanisms have been proposed to explain how algae can tolerate heavy metals. In order to better understand the mechanisms determining metal tolerance, we examined the interaction of copper with two strains of the copper-tolerant green algae Oocystis nephrocytioides, isolated from algal communities differing only in copper exposure. The strains were cultured in chemically-defined media containing 0.04 μM Cu total (pCu 12.4) or 2 μM Cu total (pCu 10.6). Growth, photosynthesis rate, content of chlorophyll a and b, copper accumulation, its cellular distribution and ultrastructural localization, as well as the influence of algal growth on extracellular copper complexation were determined. Both strains had comparable growth and photosynthesis rates. The cellular content of both chlorophyll a and b was reduced, by roughly the same extent, at pCu 10.6 compared to pCu 12.4. Copper titration of the media indicated the production of copper-complexing ligands by O. nephrocytioides cultured at pCu 12.4 that increased with increased algal density during cell growth. No additional ligands were detected at pCu 10.6. Copper-complexing ligands had a conditional stability constant of K = 10 13 at pH 7.3. The intracellular concentration of copper in O. nephrocytioides was 80 μM at pCu 12.4 and increased to 7.5 mM at pCu 10.6. The proportion of intracellular Cu accumulated increased from 8% of total Cu content at pCu 12.4 to 60% at pCu 10.6. By electron spectroscopic imaging, intracellular Cu was detected in the thylakoids and the pyrenoid of O. nephrocytioides cells. The results indicate that the tolerance of O. nephrocytioides to Cu is constitutive and does not need to be induced by previous exposure to Cu. We propose that accumulation and sequestration of Cu in thylakoids and, to a lesser extent, adsorption of copper to the algal cell surface represent the most important tolerance mechanism, for O. nephrocytioides

  15. Antimicrobial Properties of Copper Nanoparticles and Amino Acid Chelated Copper Nanoparticles Produced by Using a Soya Extract.

    Science.gov (United States)

    DeAlba-Montero, I; Guajardo-Pacheco, Jesús; Morales-Sánchez, Elpidio; Araujo-Martínez, Rene; Loredo-Becerra, G M; Martínez-Castañón, Gabriel-Alejandro; Ruiz, Facundo; Compeán Jasso, M E

    2017-01-01

    This paper reports a comparison of the antibacterial properties of copper-amino acids chelates and copper nanoparticles against Escherichia coli , Staphylococcus aureus , and Enterococcus faecalis . These copper-amino acids chelates were synthesized by using a soybean aqueous extract and copper nanoparticles were produced using as a starting material the copper-amino acids chelates species. The antibacterial activity of the samples was evaluated by using the standard microdilution method (CLSI M100-S25 January 2015). In the antibacterial activity assays copper ions and copper-EDTA chelates were included as references, so that copper-amino acids chelates can be particularly suitable for acting as an antibacterial agent, so they are excellent candidates for specific applications. Additionally, to confirm the antimicrobial mechanism on bacterial cells, MTT assay (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) was carried out. A significant enhanced antimicrobial activity and a specific strain were found for copper chelates over E. faecalis . Its results would eventually lead to better utilization of copper-amino acids chelate for specific application where copper nanoparticles can be not used.

  16. Gastrointestinal and in vitro release of copper, cadmium, indium, mercury and zinc from conventional and copper-rich amalgams

    International Nuclear Information System (INIS)

    Brune, D.; Gjerdet, N.; Paulsen, G.

    1983-01-01

    Particles of a conventional lathe-cut, a spherical non-gamma 2 and a copper amalgam have been gastrointestinally administered to rats for the purpose of evaluation of the dissolution resistance. The animals were sacrificed after 20 hrs. The contents of copper, cadmium, indium, mercury and zinc in kidney, liver, lung or blood were measured using nuclear tracer techniques. From a copper amalgam an extreme release of copper was demonstrated. This study simulates the clinical conditions of elemental release from swallowed amalgam particles after amalgam insertion or after removal of old amalgam fillings. Specimens of the same types of amalgams were also exposed to artificial saliva for a period of 10 days. The amounts of copper and mercury released were measured with flame and flameless atomic absorption spectrophotometry respectively. The levels of copper and mercury released from the copper amalgam were approximately 50 times those of the two other amalgam types studied. (author)

  17. [Newly leaching method of copper from waste print circuit board using hydrochloric acid/n-butylamine/copper sulfate].

    Science.gov (United States)

    Wang, Hong-Yan; Cui, Zhao-Jie; Yao, Ya-Wei

    2010-12-01

    A newly leaching method of copper from waste print circuit board was established by using hydrochloric acid-n-butylamine-copper sulfate mixed solution. The conditions of leaching were optimized by changing the hydrochloric acid, n-butylamine, copper sulfate,temperature and other conditions using copper as target mimics. The results indicated that copper could be leached completely after 8 h at 50 degrees C, hydrochloric acid concentration of 1.75 mol/L, n-butylamine concentration of 0.25 mol/L, and copper sulfate mass of 0.96 g. Under the conditions, copper leaching rates in waste print circuit board samples was up to 95.31% after 9 h. It has many advantages such as better effects, low cost, mild reaction conditions, leaching solution recycling.

  18. Construction of a high efficiency copper adsorption bacterial system via peptide display and its application on copper dye polluted wastewater.

    Science.gov (United States)

    Maruthamuthu, Murali Kannan; Nadarajan, Saravanan Prabhu; Ganesh, Irisappan; Ravikumar, Sambandam; Yun, Hyungdon; Yoo, Ik-Keun; Hong, Soon Ho

    2015-11-01

    For the construction of an efficient copper waste treatment system, a cell surface display strategy was employed. The copper adsorption ability of recombinant bacterial strains displaying three different copper binding peptides were evaluated in LB Luria-Bertani medium (LB), artificial wastewater, and copper phthalocyanine containing textile dye industry wastewater samples. Structural characteristics of the three peptides were also analyzed by similarity-based structure modeling. The best binding peptide was chosen for the construction of a dimeric peptide display and the adsorption ability of the monomeric and dimeric peptide displayed strains were compared. The dimeric peptide displayed strain showed superior copper adsorption in all three tested conditions (LB, artificial wastewater, and textile dye industry wastewater). When the strains were exposed to copper phthalocyanine dye polluted wastewater, the dimeric peptide display [543.27 µmol/g DCW dry cell weight (DCW)] showed higher adsorption of copper when compared with the monomeric strains (243.53 µmol/g DCW).

  19. 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

  20. Search of a plant hiperacumuladora of copper

    International Nuclear Information System (INIS)

    Hernandez Colorado, R.R.

    2003-01-01

    The objective of this investigation was to find inside the flora of Costa Rica, a plant copper hiperacumuladora. Once identified the species, you would proceed to cultivate it in vitro, stops later to make experiments of copper absorption in vitro. If the selected species was capable of hiperacumular the metal, the influence of the agents quelantes sour etilendiaminotetraacetico would be investigated (EDTA) and citric acid, in the absorption of the metal. To carry out the investigation, vegetable species were collected inside the banana property Probana located in Limon and inside a coffee plantation in Carrizal de Alajuela. The dried vegetable samples were analyzed the copper content and in the same way, with collected floor samples of the surrounding area to the plants. As satisfactory results were not obtained, the species Tagetes foetidissima and Coccosypselum hirsutum were selected. The first one was selected with base in their metabolism, which allowed to synthesize sulfurated compounds. The second were selected with base in the available information in the literature about the aluminum hiperacumulation on the part of species belonging to the family Rubiaceae, to which it belongs. The species T. foetidissima and C. hirsutum, were cultivated in vitro stops later to make experiments of copper absorption. The results obtained starting from the experiments of copper absorption for T. foetidissima were of 3626 - 7402 mg kg -1 it has more than enough it bases dry, for an environment of concentration of the metal in the means of cultivation of 20-30 mg L -1 for a lapse of fifteen days. For this species an environment of accumulation of 4251 was obtained - 6481 mg kg -1 it has more than enough it bases dry, to 20 mg L -1 of the metal, when adding him EDTA to an experimentation group and citric acid to another. In the case of C. hirsutum, hiperacumulo gets paid in concentrations of 7648 - 8786 mg kg -1 it has more than enough it bases dry, for an environment of

  1. Functional recovery of biofilm bacterial communities after copper exposure

    International Nuclear Information System (INIS)

    Boivin, Marie-Elene Y.; Massieux, Boris; Breure, Anton M.; Greve, Gerdit D.; Rutgers, Michiel; Admiraal, Wim

    2006-01-01

    Potential of bacterial communities in biofilms to recover after copper exposure was investigated. Biofilms grown outdoor in shallow water on glass dishes were exposed in the laboratory to 0.6, 2.1, 6.8 μmol/l copper amended surface water and a reference and subsequently to un-amended surface water. Transitions of bacterial communities were characterised with denaturing gradient gel electrophoresis (DGGE) and community-level physiological profiles (CLPP). Exposure to 6.8 μmol/l copper provoked distinct changes in DGGE profiles of bacterial consortia, which did not reverse upon copper depuration. Exposure to 2.1 and 6.8 μmol/l copper was found to induce marked changes in CLPP of bacterial communities that proved to be reversible during copper depuration. Furthermore, copper exposure induced the development of copper-tolerance, which was partially lost during depuration. It is concluded that bacterial communities exposed to copper contaminated water for a period of 26 days are capable to restore their metabolic attributes after introduction of unpolluted water in aquaria for 28 days. - Genetically different bacterial communities can have similar functions and tolerance to copper

  2. Immobilization of copper flotation waste using red mud and clinoptilolite.

    Science.gov (United States)

    Coruh, Semra

    2008-10-01

    The flash smelting process has been used in the copper industry for a number of years and has replaced most of the reverberatory applications, known as conventional copper smelting processes. Copper smelters produce large amounts of copper slag or copper flotation waste and the dumping of these quantities of copper slag causes economic, environmental and space problems. The aim of this study was to perform a laboratory investigation to assess the feasibility of immobilizing the heavy metals contained in copper flotation waste. For this purpose, samples of copper flotation waste were immobilized with relatively small proportions of red mud and large proportions of clinoptilolite. The results of laboratory leaching demonstrate that addition of red mud and clinoptilolite to the copper flotation waste drastically reduced the heavy metal content in the effluent and the red mud performed better than clinoptilolite. This study also compared the leaching behaviour of metals in copper flotation waste by short-time extraction tests such as the toxicity characteristic leaching procedure (TCLP), deionized water (DI) and field leach test (FLT). The results of leach tests showed that the results of the FLT and DI methods were close and generally lower than those of the TCLP methods.

  3. Copper Tolerance and Biosorption of Saccharomyces cerevisiae during Alcoholic Fermentation

    Science.gov (United States)

    Liu, Ling-ling; Jia, Bo; Zhao, Fang; Huang, Wei-dong; Zhan, Ji-cheng

    2015-01-01

    At high levels, copper in grape mash can inhibit yeast activity and cause stuck fermentations. Wine yeast has limited tolerance of copper and can reduce copper levels in wine during fermentation. This study aimed to understand copper tolerance of wine yeast and establish the mechanism by which yeast decreases copper in the must during fermentation. Three strains of Saccharomyces cerevisiae (lab selected strain BH8 and industrial strains AWRI R2 and Freddo) and a simple model fermentation system containing 0 to 1.50 mM Cu2+ were used. ICP-AES determined Cu ion concentration in the must decreasing differently by strains and initial copper levels during fermentation. Fermentation performance was heavily inhibited under copper stress, paralleled a decrease in viable cell numbers. Strain BH8 showed higher copper-tolerance than strain AWRI R2 and higher adsorption than Freddo. Yeast cell surface depression and intracellular structure deformation after copper treatment were observed by scanning electron microscopy and transmission electron microscopy; electronic differential system detected higher surface Cu and no intracellular Cu on 1.50 mM copper treated yeast cells. It is most probably that surface adsorption dominated the biosorption process of Cu2+ for strain BH8, with saturation being accomplished in 24 h. This study demonstrated that Saccharomyces cerevisiae strain BH8 has good tolerance and adsorption of Cu, and reduces Cu2+ concentrations during fermentation in simple model system mainly through surface adsorption. The results indicate that the strain selected from China’s stress-tolerant wine grape is copper tolerant and can reduce copper in must when fermenting in a copper rich simple model system, and provided information for studies on mechanisms of heavy metal stress. PMID:26030864

  4. Effectiveness acidic pre-cleaning for copper-gold ore

    Directory of Open Access Journals (Sweden)

    Antonio Clareti Pereira

    Full Text Available Abstract The presence of copper-bearing minerals is known to bring on many challenges during the cyanidation of gold ore, like high consumption of cyanide and low extraction of metal, which are undesirable impacts on the auriferous recovery in the subsequent process step. The high copper solubility in cyanide prevents the direct use of classical hydrometallurgical processes for the extraction of gold by cyanidation. Additionally, the application of a conventional flotation process to extract copper is further complicated when it is oxidized. As a result, an acid pre-leaching process was applied in order to clean the ore of these copper minerals that are cyanide consumers. The objective was to evaluate the amount of soluble copper in cyanide before and after acidic cleaning. From a gold ore containing copper, the study selected four samples containing 0.22%, 0.55%, 1.00% and 1.36% of copper. For direct cyanidation of the ore without pre-treatment, copper extraction by cyanide complexing ranged from 8 to 83%. In contrast, the pre-treatment carried out with sulfuric acid extracted 24% to 99% of initial copper and subsequent cyanidation extracted 0.13 to 1.54% of initial copper. The study also showed that the copper contained in the secondary minerals is more easily extracted by cyanide (83%, being followed by the copper oxy-hydroxide minerals (60%, while the copper contained in the manganese oxide is less complexed by cyanide (8% a 12%. It was possible to observe that minerals with low acid solubility also have low solubility in cyanide. Cyanide consumption decreased by about 2.5 times and gold recovery increased to above 94% after acidic pre-cleaning.

  5. Role of copper in the process of spermatogenesis

    Directory of Open Access Journals (Sweden)

    Mateusz Ogórek

    2017-08-01

    Full Text Available Copper (Cu is an essential trace element required for the normal development of living organisms. Due to its redox potential, copper is a cofactor in many enzymes responsible for important processes in cells. Copper deficiency has a significant influence on the reduction or the total eradication of copper-dependent enzymes in the body, thereby inhibiting cell life processes. On the other hand, copper is a very reactive element and in its free state, it can trigger the production of large amounts of free radicals, which will consequently lead to the damage of proteins and DNA. Because of those reasons, living organisms have developed precise mechanisms regulating the concentration of copper in cells. Copper also plays a very important role in male fertility. It is an essential element for the production of male gametes. The significant role of copper is also described in the processes of cell division – mitotic and meiotic. Copper-dependent enzymes such as ceruloplasmin, superoxide dismutase SOD1 and SOD3, group of metallothionein and cytochrome c oxidase are present at all stages of gametogenesis as well as in the somatic cells of the testis and in the somatic cells of epididymis. Substantial amounts of copper can also be found in liquids associated with sperm in the epididymis and prostate. Copper also affects the integral androgen distribution in terms of fertility on the line hypothalamic-pituitary-testis. Both copper increase and deficiency leads to a significant reduction in male fertility, which spans the entire spectrum of abnormalities at the sperm level, male gonad, production of hormones and distribution of micronutrients such as zinc and iron. Nowadays, the effects of copper on gametes production have become more important and are connected with the increasing levels of pollution with heavy metals in environment.

  6. Copper Tolerance and Biosorption of Saccharomyces cerevisiae during Alcoholic Fermentation.

    Science.gov (United States)

    Sun, Xiang-Yu; Zhao, Yu; Liu, Ling-Ling; Jia, Bo; Zhao, Fang; Huang, Wei-Dong; Zhan, Ji-Cheng

    2015-01-01

    At high levels, copper in grape mash can inhibit yeast activity and cause stuck fermentations. Wine yeast has limited tolerance of copper and can reduce copper levels in wine during fermentation. This study aimed to understand copper tolerance of wine yeast and establish the mechanism by which yeast decreases copper in the must during fermentation. Three strains of Saccharomyces cerevisiae (lab selected strain BH8 and industrial strains AWRI R2 and Freddo) and a simple model fermentation system containing 0 to 1.50 mM Cu2+ were used. ICP-AES determined Cu ion concentration in the must decreasing differently by strains and initial copper levels during fermentation. Fermentation performance was heavily inhibited under copper stress, paralleled a decrease in viable cell numbers. Strain BH8 showed higher copper-tolerance than strain AWRI R2 and higher adsorption than Freddo. Yeast cell surface depression and intracellular structure deformation after copper treatment were observed by scanning electron microscopy and transmission electron microscopy; electronic differential system detected higher surface Cu and no intracellular Cu on 1.50 mM copper treated yeast cells. It is most probably that surface adsorption dominated the biosorption process of Cu2+ for strain BH8, with saturation being accomplished in 24 h. This study demonstrated that Saccharomyces cerevisiae strain BH8 has good tolerance and adsorption of Cu, and reduces Cu2+ concentrations during fermentation in simple model system mainly through surface adsorption. The results indicate that the strain selected from China's stress-tolerant wine grape is copper tolerant and can reduce copper in must when fermenting in a copper rich simple model system, and provided information for studies on mechanisms of heavy metal stress.

  7. Thermodynamic data for copper. Implications for the corrosion of copper under repository conditions

    Energy Technology Data Exchange (ETDEWEB)

    Puigdomenech, I. [Royal Inst. of Tech., Stockholm (Sweden); Taxen, C. [Swedish Corrosion Inst., Stockholm (Sweden)

    2000-08-01

    The stability of copper canisters has a central role in the safety concept for the planned nuclear spent fuel repository in Sweden. The corrosion of copper canisters will be influenced by the chemical and physical environment in the near-field of the repository, and thermodynamic equilibrium calculations provide the basis for understanding this system. Thermodynamic data have been selected in this work for solids and aqueous species in the system: Cu - H{sub 2}O - H{sup +} - H{sub 2} - F{sup -} - Cl{sup -} - S{sup 2-} - SO{sub 4}{sup 2-} - NO{sub 3}{sup -} - NO{sub 2}{sup -} - NH{sub 4}{sup +} PO{sub 4}{sup 3-} - CO{sub 3}{sup 2+} . For some reactions and compounds, for which no experimental information on temperature effects was available, entropy and heat capacity values have been estimated. The compiled data were used to calculate thermodynamic equilibria for copper systems up to 100 deg C. The stability of copper in contact with granitic groundwaters has been illustrated using chemical equilibrium diagrams, with he following main conclusions: Dissolved sulphide and O{sub 2} in groundwater are the most damaging components for copper corrosion. If available, HS{sup -} will react quantitatively with copper to form a variety of sulphides. However, sulphide concentrations in natural waters are usually low, because it forms sparingly soluble solids with transition metals, including Fe(II), which is wide-spread in reducing environments. Chloride can affect negatively copper corrosion. High concentrations (e.g., [Cl{sup -}]TOT > 60 g/l) may be unfavourable for the general corrosion of copper in combination with in the following circumstances: Low pH (< 4 at 25 deg C, or < 5 at 100 deg C). The presence of other oxidants than H{sup +}. The negative effects of Cl{sup -} are emphasised at higher temperatures. The chloride-enhancement of general corrosion may be beneficial for localised corrosion: pitting and stress corrosion cracking. The concept of redox potential, E

  8. Electrokinetic remediation of copper mine tailings

    DEFF Research Database (Denmark)

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

    2007-01-01

    in similar experiments but without the bipolar electrodes. The new electrokinetic remediation design was tested on copper mine tailings with different applied electric fields, remediation times and pre-treatment. The results showed that the copper removal was increased from 8% (applying 20V for 8 days......Important process parameters to optimize in electrokinetic soil remediation are those influencing remediation time and power consumption since these directly affect the cost of a remediation action. This work shows how the electrokinetic remediation (EKR) process could be improved by implementing...... bipolar electrodes in the porous material. The bipolar electrodes in EKR meant two improvements: (1) a shorter migration pathway for the contaminant, and (2) an increased electrical conductivity in the remediation system. All together the remediation proceeded faster with lower electrical resistance than...

  9. Copper Nanoparticles: Synthesis and Biological Activity

    Science.gov (United States)

    Satyvaldiev, A. S.; Zhasnakunov, Z. K.; Omurzak, E.; Doolotkeldieva, T. D.; Bobusheva, S. T.; Orozmatova, G. T.; Kelgenbaeva, Z.

    2018-01-01

    By means of XRD and FESEM analysis, it is established that copper nanoparticles with sizes less than 10 nm are formed during the chemical reduction, which form aggregates mainly with spherical shape. Presence of gelatin during the chemical reduction of copper induced formation of smaller size distribution nanoparticles than that of nanoparticles synthesized without gelatin and it can be related to formation of protective layer. Synthesized Cu nano-powders have sufficiently high activity against the Erwinia amylovora bacterium, and the bacterial growth inhibition depends on the Cu nanoparticles concentration. At a concentration of 5 mg / ml of Cu nanoparticles, the exciter growth inhibition zone reaches a maximum value within 72 hours and the lysis zone is 20 mm, and at a concentration of 1 mg / ml this value is 16 mm, which also indicates the significant antibacterial activity of this sample.

  10. Mechanism of Selenium Loss in Copper Slag

    Science.gov (United States)

    Desai, Bhavin; Tathavadkar, Vilas; Basu, Somnath

    2018-03-01

    During smelting of copper sulfide concentrate, selenium is distributed between silica-saturated iron-silicate slag and copper-iron sulfide matte. The recovery coefficients of selenium between slag and matte were determined as a function of the initial concentration of selenium at 1523 K (1250 °C) under an inert atmosphere in a vertical tubular furnace. The initial concentration of selenium was varied by the addition of metallic selenium as well as selenium dioxide to the mixture of slag and matte. Analysis of the results indicated high affinity of selenium for matte. The apparent loss of selenium with the slag was attributed to the presence of selenium-enriched matte particles entrapped in the slag, rather than dissolved SeO2. The mechanisms proposed by previous investigators were discussed and also compared with the results of the present investigation.

  11. Polystyrene films as barrier layers for corrosion protection of copper and copper alloys.

    Science.gov (United States)

    Románszki, Loránd; Datsenko, Iaryna; May, Zoltán; Telegdi, Judit; Nyikos, Lajos; Sand, Wolfgang

    2014-06-01

    Dip-coated polystyrene layers of sub-micrometre thickness (85-500nm) have been applied on copper and copper alloys (aluminium brass, copper-nickel 70/30), as well as on stainless steel 304, and produced an effective barrier against corrosion and adhesion of corrosion-relevant microorganisms. According to the dynamic wettability measurements, the coatings exhibited high advancing (103°), receding (79°) and equilibrium (87°) contact angles, low contact angle hysteresis (6°) and surface free energy (31mJ/m(2)). The corrosion rate of copper-nickel 70/30 alloy samples in 3.5% NaCl was as low as 3.2μm/a (44% of that of the uncoated samples), and in artificial seawater was only 0.9μm/a (29% of that of the uncoated samples). Cell adhesion was studied by fluorescence microscopy, using monoculture of Desulfovibrio alaskensis. The coatings not only decreased the corrosion rate but also markedly reduced the number of bacterial cells adhered to the coated surfaces. The PS coating on copper gave the best result, 2×10(3)cells/cm(2) (1% of that of the uncoated control). © 2013 Elsevier B.V. All rights reserved.

  12. A brief review of cavity swelling and hardening in irradiated copper and copper alloys

    International Nuclear Information System (INIS)

    Zinkle, S.J.

    1990-01-01

    The literature on radiation-induced swelling and hardening in copper and its alloy is reviewed. Void formation does not occur during irradiation of copper unless suitable impurity atoms such as oxygen or helium are present. Void formation occurs for neutron irradiation temperatures of 180 to 550 degree C, with peak swelling occurring at ∼320 degree C for irradiation at a damage rate of 2 x 10 -7 dpa/s. The post-transient swelling rate has been measured to be ∼0.5%/dpa at temperatures near 400 degree C. Dispersion-strengthened copper has been found to be very resistant to void swelling due to the high sink density associated with the dispersion-stabilized dislocation structure. Irradiation of copper at temperatures below 400 degree C generally causes an increase in strength due to the formation of defect clusters which inhibit dislocation motion. The radiation hardening can be adequately described by Seeger's dispersed barrier model, with a barrier strength for small defect clusters of α ∼ 0.2. The radiation hardening apparently saturates for fluences greater than ∼10 24 n/m 2 during irradiation at room temperature due to a saturation of the defect cluster density. Grain boundaries can modify the hardening behavior by blocking the transmission of dislocation slip bands, leading to a radiation- modified Hall-Petch relation between yield strength and grain size. Radiation-enhanced recrystallization can lead to softening of cold-worked copper alloys at temperatures above 300 degree C

  13. Copper tellurium oxides - A playground for magnetism

    Science.gov (United States)

    Norman, M. R.

    2018-04-01

    A variety of copper tellurium oxide minerals are known, and many of them exhibit either unusual forms of magnetism, or potentially novel spin liquid behavior. Here, I review a number of the more interesting materials with a focus on their crystalline symmetry and, if known, the nature of their magnetism. Many of these exist (so far) in mineral form only, and most have yet to have their magnetic properties studied. This means a largely unexplored space of materials awaits our exploration.

  14. Electrochemical behaviour of alkaline copper complexes

    Indian Academy of Sciences (India)

    3.2 Triethanolamine solutions. The electrochemical spectrum obtained in 10–2 M CuSO4 solutions containing 5 × 10–1 M. NaOH + 4 × 10–2 M TEA (figure 2) during the forward sweep shows a cathodic peak (I). Figure 2. Typical cyclic voltammogram in 0⋅01 M copper sulphate + 0⋅04 M. TEA + 1⋅0 M sodium hydroxide.

  15. Computer simulation of displacement cascades in copper

    International Nuclear Information System (INIS)

    Heinisch, H.L.

    1983-06-01

    More than 500 displacement cascades in copper have been generated with the computer simulation code MARLOWE over an energy range pertinent to both fission and fusion neutron spectra. Three-dimensional graphical depictions of selected cascades, as well as quantitative analysis of cascade shapes and sizes and defect densities, illustrate cascade behavior as a function of energy. With increasing energy, the transition from production of single compact damage regions to widely spaced multiple damage regions is clearly demonstrated

  16. Copper desorption from Gelidium algal biomass.

    Science.gov (United States)

    Vilar, Vítor J P; Botelho, Cidália M S; Boaventura, Rui A R

    2007-04-01

    Desorption of divalent copper from marine algae Gelidium sesquipedale, an algal waste (from agar extraction industry) and a composite material (the algal waste immobilized in polyacrylonitrile) was studied in a batch system. Copper ions were first adsorbed until saturation and then desorbed by HNO(3) and Na(2)EDTA solutions. Elution efficiency using HNO(3) increases as pH decreases. At pH=1, for a solid to liquid ratio S/L=4gl(-1), elution efficiency was 97%, 95% and 88%, the stoichiometric coefficient for the ionic exchange, 0.70+/-0.02, 0.73+/-0.05 and 0.76+/-0.06 and the selectivity coefficient, 0.93+/-0.07, 1.0+/-0.3 and 1.1+/-0.3, respectively, for algae Gelidium, algal waste and composite material. Complexation of copper ions by EDTA occurs in a molar proportion of 1:1 and the elution efficiency increases with EDTA concentration. For concentrations of 1.4, 0.88 and 0.57 mmoll(-1), the elution efficiency for S/L=4gl(-1), was 91%, 86% and 78%, respectively, for algae Gelidium, algal waste and composite material. The S/L ratio, in the range 1-20gl(-1), has little influence on copper recovery by using 0.1M HNO(3). Desorption kinetics was very fast for all biosorbents. Kinetic data using HNO(3) as eluant were well described by the mass transfer model, considering the average metal concentration in the solid phase and the equilibrium relationship given by the mass action law. The homogeneous diffusion coefficient varied between 1.0 x 10(-7)cm(2)s(-1) for algae Gelidium and 3.0 x 10(-7)cm(2)s(-1) for the composite material.

  17. Copper slag concrete admixed with polypropylene fibres

    OpenAIRE

    Chakrawarthi, Vijayaprabha; Darmar, Brindha; Elangovan, Ashokkumar

    2016-01-01

    A sustainable concrete design has become an imperative requirement for the present-day concrete industry. A part of an extensive research project aimed at studying possibilities for using copper slag (CS) and polypropylene (PP) fibres in concrete is presented and analysed. Measurements were conducted to investigate the workability, density, compressive strength, tensile strength, and micro-structural properties of concrete, as well as the ultimate load carrying capacity of reinforced-concrete...

  18. Corrosion behaviour of high copper dental amalgams.

    Science.gov (United States)

    Yap, A U J; Ng, B L; Blackwood, D J

    2004-06-01

    This study evaluated the corrosion behaviour of two high copper dental amalgam alloys [Dispersalloy (Dentsply-Caulk) and Tytin (Kerr)] in different electrolytes. Amalgam specimens were prepared, coupled to a copper wire, cemented into glass tubes and polished to a 600-grit finish. A corrosion cell was prepared using a carbon counter-electrode, a standard calomel electrode as the reference and amalgam as the working electrode. The alloys were tested in the following mediums at 37 degrees C: (i) artificial saliva based on Fusayama's solution (FS), (ii) artificial saliva with citric acid adjusted to pH 4.0 (FC) and (iii) 1% sodium chloride solution (SC). Corrosion potentials (E(corr)) and corrosion rates (I(corr)) were determined using potentiostatic and impedance spectroscopy methods. Data was subjected to anova/Scheffe's post hoc test at 0.05 significance level. For both alloys, the corrosion potential in FS was significantly greater than in SC. Corrosion potential of Tytin in FS and SC was also significantly greater than in FC. The corrosion rate of Dispersalloy in FC was significantly greater than in FS and SC. For Tytin, corrosion rate in SC was significantly greater than in FS and FC. Although no significant difference in corrosion potential/rate was observed between the alloys when tested in FS, significant differences were observed when electrochemical testing was carried out in FC and SC. The corrosion behaviour of high copper amalgam alloys are both material and environment dependent. Certain food substances may increase the corrosion of high copper amalgams.

  19. Copper Tellurium Oxides - A Playground for Magnetism.

    Energy Technology Data Exchange (ETDEWEB)

    Norman, M. R.

    2018-04-15

    A variety of copper tellurium oxide minerals are known, and many of them exhibit either unusual forms of magnetism, or potentially novel spin liquid behavior. Here, I review a number of the more interesting materials with a focus on their crystalline symmetry and, if known, the nature of their magnetism. Many of these exist (so far) in mineral form only, and most have yet to have their magnetic properties studied. This means a largely unexplored space of materials awaits our exploration.

  20. The effects of copper proximity on oxalate production in Fibroporia radiculosa

    Science.gov (United States)

    Katie M. Jenkins; Carol A. Clausen; Frederick Green III

    2014-01-01

    Copper remains a key component used in wood preservatives available today. However, the observed tolerance of several critical wood rotting organisms continues to be problematic. Tolerance to copper has been linked to the production and accumulation of oxalate, which precipitates copper into insoluble copper-oxalate crystals, thus inactivating copper ions. The purpose...

  1. Gold, nickel and copper mining and processing.

    Science.gov (United States)

    Lightfoot, Nancy E; Pacey, Michael A; Darling, Shelley

    2010-01-01

    Ore mining occurs in all Canadian provinces and territories except Prince Edward Island. Ores include bauxite, copper, gold, iron, lead and zinc. Workers in metal mining and processing are exposed, not only to the metal of interest, but also to various other substances prevalent in the industry, such as diesel emissions, oil mists, blasting agents, silica, radon, and arsenic. This chapter examines cancer risk related to the mining of gold, nickel and copper. The human carcinogenicity of nickel depends upon the species of nickel, its concentration and the route of exposure. Exposure to nickel or nickel compounds via routes other than inhalation has not been shown to increase cancer risk in humans. As such, cancer sites of concern include the lung, and the nasal sinus. Evidence comes from studies of nickel refinery and leaching, calcining, and sintering workers in the early half of the 20th century. There appears to be little or no detectable risk in most sectors of the nickel industry at current exposure levels. The general population risk from the extremely small concentrations detectable in ambient air are negligible. Nevertheless, animal carcinogenesis studies, studies of nickel carcinogenesis mechanisms, and epidemiological studies with quantitative exposure assessment of various nickel species would enhance our understanding of human health risks associated with nickel. Definitive conclusions linking cancer to exposures in gold and copper mining and processing are not possible at this time. The available results appear to demand additional study of a variety of potential occupational and non-occupational risk factors.

  2. ANTIMICROBIAL ACTIVITY OF COPPER(II COMPLEXES

    Directory of Open Access Journals (Sweden)

    Andrea Čongrádyová

    2014-02-01

    Full Text Available Two novel copper(II 5-chlorosalicylate complexes with either 1,10-phenantroline or its methyl derivative 2,9-dimethyl-1,10-phenanthroline (neocuproine have been prepared and studied. A potential antimicrobial or antifungal activity of both complexes has been tested on prokaryotic Escherichia coli and eukaryotic Saccharomyces cerevisiae model organisms. Crystal structure of [Cu(phen(5-Clsal(5-ClsalH2]2 a dimeric structure, whereas the second complex of formula [Cu(H2O(5-Clsal(Neo] has been shown to be monomeric. Our results confirmed the toxic effect of prepared copper complexes as well as bioactive ligands on the yeast and bacteria growth. The effect of copper complexes was stronger compared to the solutions of free ligands. Our preliminary results showed that the complex [Cu(H2O(5-Clsal(Neo] exhibited higher antimicrobial activity compared to the complex [Cu(phen(5-Clsal(5-ClsalH2]2.

  3. 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.

  4. Transfer of Copper from an Amyloid to a Natural Copper-Carrier Peptide with a Specific Mediating Ligand.

    Science.gov (United States)

    Nguyen, Michel; Bijani, Christian; Martins, Nathalie; Meunier, Bernard; Robert, Anne

    2015-11-16

    The oxidative stress that arises from the catalytic reduction of dioxygen by Cu(II/I)-loaded amyloids is the major pathway for neuron death that occurs in Alzheimer's disease. In this work, we show that bis-8(aminoquinoline) ligands, copper(II) specific chelators, are able to catalytically extract Cu(II) from Cu-Aβ1-16 and then completely release Cu(I) in the presence of glutathione to provide a Cu(I)-glutathione complex, a biological intermediate that is able to deliver copper to apo forms of copper-protein complexes. These data demonstrate that bis-8(aminoquinolines) can perform the transfer of copper ions from the pathological Cu-amyloid complexes to regular copper-protein complexes. These copper-specific ligands assist GSH to recycle Cu(I) in an AD brain and consequently slow down oxidative damage that is due to copper dysregulation in Alzheimer's disease. Under the same conditions, we have shown that the copper complex of PBT2, a mono(8-hydroxyquinoline) previously used as a drug candidate, does not efficiently release copper in the presence of GSH. In addition, we report that GSH itself was unable to fully abstract copper ions from Cu-β-amyloid complexes. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

    Directory of Open Access Journals (Sweden)

    George J. Brewer

    2015-12-01

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

  6. Developing radiopure copper alloys for high strength low background applications

    Science.gov (United States)

    Suriano, A. M.; Howard, S. M.; Christofferson, C. D.; Arnquist, I. J.; Hoppe, E. W.

    2018-01-01

    High purity copper continues to play an important role for ultra-low-background detectors. Measurements of rare nuclear decays, e.g. neutrinoless double-beta decay, and searches for dark matter can require construction materials that have high thermal and electrical conductivity with bulk radiopurity less than one micro-Becquerel per kilogram. However, experiments currently using components constructed of radiopure electroformed copper struggle with design of structural and mechanical parts due to the physical properties of pure copper. A higher strength material which possesses many of the favorable attributes of copper yet remains radiopure is desired. A number of copper alloying candidates which may provide improved mechanical performance and adequate radiopurity were considered. Development of an electrodeposited copper-chrome alloy from additive-free electrolyte systems is discussed. The resulting material is shown to possess high strength and meets the aforementioned radiopurity goals.

  7. Remediation of copper in vineyards--a mini review.

    Science.gov (United States)

    Mackie, K A; Müller, T; Kandeler, E

    2012-08-01

    Viticulturists use copper fungicide to combat Downy Mildew. Copper, a non-degradable heavy metal, can accumulate in soil or leach into water sources. Its accumulation in topsoil has impacted micro and macro organisms, spurring scientists to research in situ copper removal methods. Recent publications suggest that microorganism assisted phytoextraction, using plants and bacteria to actively extract copper, is most promising. As vineyards represent moderately polluted sites this technique has great potential. Active plant extraction and chelate assisted remediation extract too little copper or risk leaching, respectively. However, despite interesting pot experiment results using microorganism assisted phytoextraction, it remains a challenge to find plants that primarily accumulate copper in their shoots, a necessity in vineyards where whole plant removal would be time consuming and financially cumbersome. Vineyard remediation requires a holistic approach including sustainable soil management, proper plant selection, increasing biodiversity and microorganisms. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Moderate Dilution of Copper Slag by Natural Gas

    Science.gov (United States)

    Zhang, Bao-jing; Zhang, Ting-an; Niu, Li-ping; Liu, Nan-song; Dou, Zhi-he; Li, Zhi-qiang

    2018-01-01

    To enable use of copper slag and extract the maximum value from the contained copper, an innovative method of reducing moderately diluted slag to smelt copper-containing antibacterial stainless steel is proposed. This work focused on moderate dilution of copper slag using natural gas. The thermodynamics of copper slag dilution and ternary phase diagrams of the slag system were calculated. The effects of blowing time, temperature, matte settling time, and calcium oxide addition were investigated. The optimum reaction conditions were identified to be blowing time of 20 min, reaction temperature of 1250°C, settling time of 60 min, CaO addition of 4% of mass of slag, natural gas flow rate of 80 mL/min, and outlet pressure of 0.1 MPa. Under these conditions, the Fe3O4 and copper contents of the residue were 7.36% and 0.50%, respectively.

  9. Intense pulsed light sintering of copper nanoink for printed electronics

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hak-Sung; Dhage, Sanjay R.; Shim, Dong-Eun [University of California, Mechanical and Aerospace Engineering Department, Los Angeles, CA (United States); Hahn, H.T. [University of California, Mechanical and Aerospace Engineering Department, Los Angeles, CA (United States); University of California, Material Science and Engineering Department, California NanoSystems Institute, Los Angeles, CA (United States)

    2009-12-15

    An intense pulsed light (IPL) from a xenon flash lamp was used to sinter copper nanoink printed on low-temperature polymer substrates at room temperature in ambient condition. The IPL can sinter the copper nanoink without damaging the polymer substrates in extremely short time (2 ms). The microstructure of the sintered copper film was investigated using X-ray powder diffraction (XRD), optical microscopy, scanning electron microscopy (SEM), X-ray micro tomography, and atomic force microscopy (AFM). The sintered copper film has a grainy structure with neck-like junctions. The resulting resistivity was 5{mu}{omega} cm of electrical resistivity which is only 3 times as high as that of bulk copper. The IPL sintering technique allows copper nanoparticles to be used in inkjet printing on low-temperature substrates such as polymers in ambient conditions. (orig.)

  10. Atmospheric corrosion of copper under wet/dry cyclic conditions

    Energy Technology Data Exchange (ETDEWEB)

    EL-Mahdy, Gamal A. [Department of Metallurgical System Engineering, Yonsei University, 134-Shinchon-dong, Seodaemun-Ku, Seoul, 120-749 (Korea, Republic of)

    2005-06-01

    The polarization resistance of copper subjected to NaCl and an ammonium sulfate solution under wet/dry cycling conditions was monitored using an EIS impedance technique. The copper samples were exposed to 1 h of immersion using different solutions of pH, temperature and surface orientation and 7 h of drying. The copper plates corroded more substantially on the skyward side than those for a ground ward side. The degree of protection copper oxide provides decrease in an acidic medium (pH 4) more than in a neutral medium (pH 7). The corrosion rate of copper increases rapidly during the initial stages of exposure then decreases slowly and eventually attains the steady state during the last stages of exposure. The corrosion products were analyzed using X-ray diffraction. The corrosion mechanism for copper studied under wet/dry cyclic conditions was found to proceed under the dissolution-precipitation mechanism.

  11. Effect of oral contraceptive progestins on serum copper concentration

    DEFF Research Database (Denmark)

    Berg, Gabriele; Kohlmeier, L; Brenner, H

    1998-01-01

    OBJECTIVES: Recent epidemiologic studies have shown an increased mortality from cardiovascular diseases in people with higher serum copper levels. Even though higher serum copper concentration in women using oral contraceptives is well known, there is still uncertainty about the influence of newer......-1988. SUBJECTS: Nonpregnant and nonlactating women aged 18-44 y (n = 610). RESULTS: Overall, the use of oral contraceptives was positively associated with serum copper concentration in by bi- and multivariable linear regression models with log-transformed values of serum copper concentration as dependend...... variable and oral contraceptive preparations and potential confounding variables as independent variables. Serum copper concentration in women using oral contraceptives varied more strongly by different progestin compounds than by estrogen contents. The highest increase of serum copper was seen in women...

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

    Science.gov (United States)

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

    2012-02-16

    Transition metals such as iron, zinc, copper, and manganese are essential for the growth and development of organisms ranging from bacteria to mammals. Numerous studies have focused on the impact of iron availability during bacterial and fungal infections, and increasing evidence suggests that copper is also involved in microbial pathogenesis. Not only is copper an essential cofactor for specific microbial enzymes, but several recent studies also strongly suggest that copper is used to restrict pathogen growth in vivo. Here, we review evidence that animals use copper as an antimicrobial weapon and that, in turn, microbes have developed mechanisms to counteract the toxic effects of copper. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Towards an all-copper redox flow battery based on a copper-containing ionic liquid.

    Science.gov (United States)

    Schaltin, Stijn; Li, Yun; Brooks, Neil R; Sniekers, Jeroen; Vankelecom, Ivo F J; Binnemans, Koen; Fransaer, Jan

    2016-01-07

    The first redox flow battery (RFB), based on the all-copper liquid metal salt [Cu(MeCN)4][Tf2N], is presented. Liquid metal salts (LMS) are a new type of ionic liquid that functions both as solvent and electrolyte. Non-aqueous electrolytes have advantages over water-based solutions, such as a larger electrochemical window and large thermal stability. The proof-of-concept is given that LMSs can be used as the electrolyte in RFBs. The main advantage of [Cu(MeCN)4][Tf2N] is the high copper concentration, and thus high charge and energy densities of 300 kC l(-1) and 75 W h l(-1) respectively, since the copper(i) ions form an integral part of the electrolyte. A Coulombic efficiency up to 85% could be reached.

  14. Fatigue performance of copper and copper alloys before and after irradiation with fission neutrons

    International Nuclear Information System (INIS)

    Singh, B.N.; Toft, P.; Stubbins, J.F.

    1997-05-01

    The fatigue performance of pure copper of the oxygen free, high conductivity (OFHC) grade and two copper alloys (CuCrZr and CuAl-25) was investigated. Mechanical testing and microstructural analysis were carried out to establish the fatigue life of these materials in the unirradiated and irradiated states. The present report provides the first information on the ability of these copper alloys to perform under cyclic loading conditions when they have undergone significant irradiation exposure. Fatigue specimens of OFHC-Cu, CuCrZr and CuAl-25 were irradiated with fission neutrons in the DR-3 reactor at Risoe with a flux of ∼2.5 x 10 17 n/m 2 s (E > 1 MeV) to fluence levels of 1.5 - 2.5 x 10 24 n/m 2 s (E > 1 MeV) at ∼47 and 100 deg. C. Specimens irradiated at 47 deg. C were fatigue tested at 22 deg. C, whereas those irradiated at 100 deg. C were tested at the irradiation temperature. The major conclusion of the present work is that although irradiation causes significant hardening of copper and copper alloys, it does not appear to be a problem for the fatigue life of these materials. In fact, the present experimental results clearly demonstrate that the fatigue performance of the irradiated CuAl-25 alloy is considerably better in the irradiated than that in the unirradiated state tested both at 22 and 100 deg. C. This improvement, however, is not so significant in the case of the irradiated OFHC-copper and CuCrZr alloy tested at 22 deg. C. These conclusions are supported by the microstructural observations and cyclic hardening experiments. (au) 4 tabs., 26 ills., 10 refs

  15. Demands made on high-purity copper for special purposes

    International Nuclear Information System (INIS)

    Roettges, D.

    1977-01-01

    The properties (electrical resistivity, residual impurities) of high-purity copper produced on a technical scale are reported as well as its practical applications. The paper discusses a high-oxygen copper (SV) with low residual resistivity at low temperatures and an oxygen-free (hydrogen-stable) copper (BE electronic) with low gas content. The SV quality has been specially developed for use as stabilizer in superconductors while the BE quality is used in high and ultrahigh vacuum. (GSC) [de

  16. The Environmental Impact of the Future Anthropogenic Copper Cycle

    OpenAIRE

    Løhre, Anne-Jori S

    2014-01-01

    This master`s thesis has discussed two problems of modern society; shortage of copper resources and an increase of electricity use and global warming potential (GWP) from copper production in the future. Unlike most studies regarding environmental impacts from copper production, this study is; comprehensive considering that it includes a dynamic life cycle and is forward-looking regarding a number of factors which have high relevance for the result. The methodology of life cycle analysis (LCA...

  17. Copper ions and coordination complexes as novel carbapenem adjuvants

    OpenAIRE

    Djoko, Karrera Y.; Achard, Maud E. S.; Phan, Minh-Duy; Lo, Alvin W.; Miraula, Manfredi; Prombhul, Sasiprapa; Hancock, Steven J.; Peters, Kate M.; Sidjabat, Hanna; Harris, Patrick N.; Mitić, Nataša; Walsh, Timothy R.; Anderson, Gregory J.; Shafer, William M.; Paterson, David L.

    2017-01-01

    Carbapenem-resistant Enterobacteriaceae are an urgent threat to global human health. These organisms produce β-lactamases with carbapenemase activity, such as the metallo-β-lactamase NDM-1, which is notable due to its association with mobile genetic elements and the lack of a clinically useful inhibitor. Here we examined the ability of copper to inhibit the activity of NDM-1 and explored the potential of a copper coordination complex as a mechanism to efficiently deliver copper as an adjuvant...

  18. Synthesis, Characterization and DNA Cleavage of Copper(II ...

    African Journals Online (AJOL)

    for. Copper(II)-DTT complex because of deprotonation of the –SH group of DTT molecule after forming a covalent bond with Copper (II) ion through the Sulphur atom. The non-involvement of the –OH group of DTT in copper ion co- ordination is evident from the fact that the –OH stretching frequencies of DTT and its complex.

  19. The industrial separation of copper and arsenic as sulfides

    Science.gov (United States)

    Gabb, P. J.; Davies, A. L.

    1999-09-01

    At the Kennecott Utah copper smelter in Magna, Utah, bleed streams from the refinery tankhouse and precious-metals plant are combined with smelter weak acid and electrostatic precipitator dust to produce leach solutions containing copper and impurities. Copper and arsenic are precipitated from the solutions as sulfides in a two-stage continuous process that enables excess arsenic to be removed from the circuit and routed to hazardous waste disposal as a highly concentrated material.

  20. Long-term stake evaluations of waterborne copper systems

    Science.gov (United States)

    Stan Lebow; Cherilyn Hatfield; Douglas Crawford; Bessie Woodward

    2003-01-01

    Limitations on the use of chromated copper arsenate (CCA) have heightened interest in use of arsenic-free copper-based alternatives. For decades, the USDA Forest Products Laboratory has been evaluating several of these systems in stake plots. Southern Pine 38- by 89- by 457-mm (1.5- by 3.5- by 18-inch) stakes were treated with varying concentrations of acid copper...

  1. Modification of surface properties of copper-refractory metal alloys

    Science.gov (United States)

    Verhoeven, J.D.; Gibson, E.D.

    1993-10-12

    The surface properties of copper-refractory metal (CU-RF) alloy bodies are modified by heat treatments which cause the refractory metal to form a coating on the exterior surfaces of the alloy body. The alloys have a copper matrix with particles or dendrites of the refractory metal dispersed therein, which may be niobium, vanadium, tantalum, chromium, molybdenum, or tungsten. The surface properties of the bodies are changed from those of copper to that of the refractory metal.

  2. Stress corrosion cracking of copper canisters

    Energy Technology Data Exchange (ETDEWEB)

    King, Fraser (Integrity Corrosion Consulting Limited (Canada)); Newman, Roger (Univ. of Toronto (Canada))

    2010-12-15

    A critical review is presented of the possibility of stress corrosion cracking (SCC) of copper canisters in a deep geological repository in the Fennoscandian Shield. Each of the four main mechanisms proposed for the SCC of pure copper are reviewed and the required conditions for cracking compared with the expected environmental and mechanical loading conditions within the repository. Other possible mechanisms are also considered, as are recent studies specifically directed towards the SCC of copper canisters. The aim of the review is to determine if and when during the evolution of the repository environment copper canisters might be susceptible to SCC. Mechanisms that require a degree of oxidation or dissolution are only possible whilst oxidant is present in the repository and then only if other environmental and mechanical loading conditions are satisfied. These constraints are found to limit the period during which the canisters could be susceptible to cracking via film rupture (slip dissolution) or tarnish rupture mechanisms to the first few years after deposition of the canisters, at which time there will be insufficient SCC agent (ammonia, acetate, or nitrite) to support cracking. During the anaerobic phase, the supply of sulphide ions to the free surface will be transport limited by diffusion through the highly compacted bentonite. Therefore, no HS. will enter the crack and cracking by either of these mechanisms during the long term anaerobic phase is not feasible. Cracking via the film-induced cleavage mechanism requires a surface film of specific properties, most often associated with a nano porous structure. Slow rates of dissolution characteristic of processes in the repository will tend to coarsen any nano porous layer. Under some circumstances, a cuprous oxide film could support film-induced cleavage, but there is no evidence that this mechanism would operate in the presence of sulphide during the long-term anaerobic period because copper sulphide

  3. Stress corrosion cracking of copper canisters

    International Nuclear Information System (INIS)

    King, Fraser; Newman, Roger

    2010-12-01

    A critical review is presented of the possibility of stress corrosion cracking (SCC) of copper canisters in a deep geological repository in the Fennoscandian Shield. Each of the four main mechanisms proposed for the SCC of pure copper are reviewed and the required conditions for cracking compared with the expected environmental and mechanical loading conditions within the repository. Other possible mechanisms are also considered, as are recent studies specifically directed towards the SCC of copper canisters. The aim of the review is to determine if and when during the evolution of the repository environment copper canisters might be susceptible to SCC. Mechanisms that require a degree of oxidation or dissolution are only possible whilst oxidant is present in the repository and then only if other environmental and mechanical loading conditions are satisfied. These constraints are found to limit the period during which the canisters could be susceptible to cracking via film rupture (slip dissolution) or tarnish rupture mechanisms to the first few years after deposition of the canisters, at which time there will be insufficient SCC agent (ammonia, acetate, or nitrite) to support cracking. During the anaerobic phase, the supply of sulphide ions to the free surface will be transport limited by diffusion through the highly compacted bentonite. Therefore, no HS. will enter the crack and cracking by either of these mechanisms during the long term anaerobic phase is not feasible. Cracking via the film-induced cleavage mechanism requires a surface film of specific properties, most often associated with a nano porous structure. Slow rates of dissolution characteristic of processes in the repository will tend to coarsen any nano porous layer. Under some circumstances, a cuprous oxide film could support film-induced cleavage, but there is no evidence that this mechanism would operate in the presence of sulphide during the long-term anaerobic period because copper sulphide

  4. Photoelectrochemistry of copper(I) acetylide films electrodeposited onto copper electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Zotti, G.; Cattarin, S.; Mengoli, G.; Fleischmann, M.; Peter, L.M.

    1986-01-01

    Films of copper acetylide (Cu/sub 2/C/sub 2/) were grown electrochemically on copper and characterized by transmittance and reflectance techniques. The photoelectrochemical properties of the filmed electrodes in alkaline solution indicate that Cu/sub 2/C/sub 2/ behaves as a p-type semiconducting material (1.5 eV band gap). The photocurrents depend on film thickness and aging and high resistivity or recombination losses limit the quantum yield to some 4% for thicknesses of practical importance (250 nm).

  5. Oxygen consumption under copper and zinc stress in Perna viridis

    OpenAIRE

    Prabhudeva, K.N.; Menon, N.R.

    1986-01-01

    The rate of oxygen consumption by Perna viridis pre-exposed to copper and zinc was studied. Those test individuals pre-exposed to various zinc concentrations showed variability in oxygen consumption irrespective of concentrations and pre-exposure period. While those animals pre-exposed to various copper concentrations registered decrease in oxygen consumption at concentrations above 0.06 p.p.m. copper, pre-exposure to concentrations below 0.02 p.p.m. copper did not result in any clear cut cha...

  6. Vermiculite decorated with copper nanoparticles: Novel antibacterial hybrid material

    Science.gov (United States)

    Drelich, Jaroslaw; Li, Bowen; Bowen, Patrick; Hwang, Jiann-Yang; Mills, Owen; Hoffman, Daniel

    2011-09-01

    Vermiculite decorated with copper nanoparticles is a new antibacterial material that was prepared in this study through ion-exchange process and hydrogen reduction. The replacement of magnesium ions in interlayer structure was carried out using concentrated copper sulfate solutions at elevated temperature. Copper ions were reduced to elemental copper at 400-600 °C using hydrogen as the reducing agent. During the reduction process copper diffused primarily to vermiculite surface regions and formed copper nanoparticles with a broad range of sizes, from ˜1 to 400 nm. Strong adhesion of copper nanoparticles to the vermiculite carrier makes this hybrid very stable and durable. The new vermiculite-metallic copper hybrid material shows strong antibacterial activity against Staphylococcus aureus at 37 °C. Vermiculite is an inexpensive mineral that is very stable under a wide range of industrial and environmental conditions, and extensively used as filler in fireproof materials, plastics, paints and lightweight concrete, so the addition of copper as an antibacterial agent opens new avenues for the application of vermiculite in consumer products and other areas.

  7. Enhanced copper removal from activated sludge using bioferric/selectors

    Energy Technology Data Exchange (ETDEWEB)

    McCormick, M.W.; Cannon, F.S. [Pennsylvania State Univ., University Park, PA (United States). Dept. of Civil and Environmental Engineering

    1999-05-01

    Effluent copper concentrations from a pilot-scale conventional activated-sludge system (control) were compared with those from a conventional pilot treatment process that also integrated bioferric/selector units. The bioferric/selector units employed iron coagulation within the activated-sludge basin and also provided storage of activated sludge in a nonaerated selector for a period of 18--24 h. During pseudo-steady-state operation over a 30-day period, the systems employing the bioferric/selector treatment consistently yielded lower effluent copper concentrations than did the controls. Although influent copper concentration ranged from 126 to 723 ppb (228 ppb average), the two bioferric/selector units achieved an average effluent copper concentration of 22 ppb, whereas the two conventional controls achieved an average of 40 ppb. The difference in copper concentrations between the bioferric/selector units and the controls was statistically significant to the 99.5% confidence level when comparing effluent copper concentrations as a function of mixed-liquor volatile suspended solids (MLVSS). For both conditions, lower effluent copper corresponded to higher MLVSS, and for equal levels of MLVSS, the bioferric/selector units statistically achieved lower effluent copper concentrations than did the controls. Likewise, Freundlich isotherm plots indicated that the MLVSS (or MLSS) that had undergone the bioferric/selector treatment achieved statistically greater capture of copper than did their control counterparts.

  8. Microstructural characterization of copper corrosion in aqueous and soil environments

    International Nuclear Information System (INIS)

    Srivastava, A.; Balasubramaniam, R.

    2005-01-01

    Scanning electron microscopy has been used to investigate the surface films on pure copper after exposure to different aqueous and soil environments, containing chloride, sulfide and ammonium salts. The morphology of the films formed on copper surface in aqueous and soil environments was different for the same amount of pollutants. The surface films formed in soil environments were not homogenous in contrast to the films formed in aqueous environments. The damaging effect of chloride ions and the benign role of sulfide ions were revealed in both the environments. Local compositional analysis confirmed that the surface films formed on copper consisted predominantly of copper and oxygen

  9. Corrosion of copper alloys in sulphide containing district heting systems

    DEFF Research Database (Denmark)

    Thorarinsdottir, R.I.; Maahn, Ernst Emanuel

    1999-01-01

    Copper and some copper alloys are prone to corrosion in sulphide containing geothermal water analogous to corrosion observed in district heating systems containing sulphide due to sulphate reducing bacteria. In order to study the corrosion of copper alloys under practical conditions a test...... was carried out at four sites in the Reykjavik District Heating System. The geothermal water chemistry is different at each site. The corrosion rate and the amount and chemical composition of deposits on weight loss coupons of six different copper alloys are described after exposure of 12 and 18 months......, respectively. Some major differences in scaling composition and the degree of corrosion attack are observed between alloys and water types....

  10. The effect of copper pre-cleaning on graphene synthesis.

    Science.gov (United States)

    Kim, Soo Min; Hsu, Allen; Lee, Yi-Hsien; Dresselhaus, Mildred; Palacios, Tomás; Kim, Ki Kang; Kong, Jing

    2013-09-13

    Copper foil is the most common substrate to synthesize monolayer graphene by chemical vapor deposition (CVD). The surface morphology and conditions of the copper foil can be very different depending on the various suppliers or different batches. These surface properties of copper strongly affect the growth behavior of graphene, thus rendering the growth conditions irreproducible when different batches of Cu foil are used. Furthermore, the quality of the graphene is severely affected as well. In this work, we report a facile method of copper pre-cleaning to improve the graphene quality and the reproducibility of the growth process. We found that the commercial Ni etchant (based on nitric acid) or nitric acid is the most effective cleaning agent among various acidic or basic solutions. The graphene grown on thus-treated copper surfaces is very clean and mostly monolayer when observed under scanning electron microscopy (SEM) and optical imaging, as compared to the graphene grown on untreated copper foil. Different batches (but with the same catalog number) of copper foil from Alfa Aesar Company were examined to explore the effect of copper pre-cleaning; consistent growth results were obtained when pre-cleaning was used. This method overcomes a commonly encountered problem in graphene growth and could become one of the standard protocols for preparing the copper foil substrate for growing graphene or other 2D materials.

  11. Copper and zinc concentrations in serum of healthy Greek adults

    International Nuclear Information System (INIS)

    Kouremenou-Dona, Eleni; Dona, Artemis; Papoutsis, John; Spiliopoulou, Chara

    2006-01-01

    Serum copper and zinc concentrations of 506 (414 males and 92 females) apparently healthy Greek blood donors aged 18-60 years old were determined by flame atomic absorption spectrometry. The mean copper and zinc concentrations were 115.46 ± 23.56 μg/dl and 77.11 ± 17.67 μg/dl, respectively. The mean value for copper and zinc in females was higher than in males, although the difference for zinc was smaller than the one observed for copper. When the subjects were divided into various age groups there appeared to be some increase in copper concentration as a function of age, whereas zinc concentration did not change. There were no significant variations in serum copper and zinc concentrations due to place of residence, occupation and socioeconomic status. This study is the first one evaluating the serum status of copper and zinc in healthy Greeks and it has shown that they are at the highest concentration range for copper and the lowest for zinc compared to literature data on copper and zinc levels for various countries

  12. Remediation of copper in vineyards – A mini review

    International Nuclear Information System (INIS)

    Mackie, K.A.; Müller, T.; Kandeler, E.

    2012-01-01

    Viticulturists use copper fungicide to combat Downy Mildew. Copper, a non-degradable heavy metal, can accumulate in soil or leach into water sources. Its accumulation in topsoil has impacted micro and macro organisms, spurring scientists to research in situ copper removal methods. Recent publications suggest that microorganism assisted phytoextraction, using plants and bacteria to actively extract copper, is most promising. As vineyards represent moderately polluted sites this technique has great potential. Active plant extraction and chelate assisted remediation extract too little copper or risk leaching, respectively. However, despite interesting pot experiment results using microorganism assisted phytoextraction, it remains a challenge to find plants that primarily accumulate copper in their shoots, a necessity in vineyards where whole plant removal would be time consuming and financially cumbersome. Vineyard remediation requires a holistic approach including sustainable soil management, proper plant selection, increasing biodiversity and microorganisms. - Highlights: ► We describe copper distribution and availability in vineyards. ► We explain the environmental impact of copper on organisms, plants and processes. ► We detail possible remediation methods within vineyards. ► Microbially assisted phytoremediation is the most promising remediation method. ► A solution requires an interdisciplinary approach between plants, soil and vines. - This review is significant because it highlights prospective remediation methods usable in copper contaminated vineyards.

  13. Ultrahigh reactivity and grave nanotoxicity of copper nanoparticles

    International Nuclear Information System (INIS)

    Huan Meng; Zhen Chen; Chengcheng Zhang; Yun Wang; Yuliang Zhao

    2007-01-01

    Recently, it was reported that the toxicity of copper particles increases with the decrease of the particle size on a mass basis. To understand this phenomenon, inductively coupled plasma mass spectrometry (ICP-MS) techniques and in vitro chemical studies were carried out to explore how they produce toxicity in vivo. The results suggest that when the sizes of particles become small and down to a nanoscale, copper becomes extremely reactive in a simulative intracorporeal environment. The nanosized copper particles consume the hydrogen ions in stomach more quickly than micron ones. These processes further convert the copper nanoparticles into cupric ions whose toxicity is very high in vivo. (author)

  14. Microplastic Deformation of Submicrocrystalline Copper at Room and Elevated Temperatures

    Science.gov (United States)

    Dudarev, E. F.; Pochivalova, G. P.; Tabachenko, A. N.; Maletkina, T. Yu.; Skosyrskii, A. B.; Osipov, D. A.

    2017-02-01

    of investigations of submicrocrystalline copper subjected to cold rolling after abc pressing by methods of backscatter electron diffraction and x-ray diffraction analysis are presented. It is demonstrated that after such combined intensive plastic deformation, the submicrocrystalline structure with average grain-subgrain structure elements having sizes of 0.63 μm is formed with relative fraction of high-angle grain boundaries of 70% with texture typical for rolled copper. Results of investigation of microplastic deformation of copper with such structure at temperatures in the interval 295-473 K and with submicrocrystalline structure formed by cold rolling of coarse-grained copper are presented.

  15. Studies on CO2-laser Hybrid-Welding of Copper

    DEFF Research Database (Denmark)

    Nielsen, Jakob Skov; Olsen, Flemming Ove; Bagger, Claus

    2005-01-01

    CO2-laser welding of copper is known to be difficult due to the high heat conductivity of the material and the high reflectivity of copper at the wavelength of the CO2-laser light. THis paper presents a study of laser welding of copper, applying laser hybrid welding. Welding was performed...... as a hybrid CO2-laser and GTAW welding process in 2 mm pure copper sheets. The purpose was to identify maximum welding speeds for the three independent welding processes, i.e. GTAW alone, laser alone and combined processes. After welding, representative welds were quality assesed according to inernational...

  16. Use of copper powder extinguishers on lithium fires

    Science.gov (United States)

    Leonard, Joseph T.; Burns, R.; Beither, J.; Ouelette, R.; Darwin, R.

    1994-07-01

    The suitability of using copper powder extinguishers for controlling lithium fires resulting from a damaged Mark 50 Torpedo boiler assembly was evaluated. The results indicated that under ideal conditions, i.e., unobstructed access to the fire, copper powder will extinguish burning lithium when applied at the recommended rate of 4.5 kg (10 lb) of copper per 0.45 kg (1 lb) of lithium. However, the presence of obstructions or of high spots on the surface of the burning lithium increases the quantity of copper powder required for extinguishment.

  17. The effect of copper pre-cleaning on graphene synthesis

    Science.gov (United States)

    Kim, Soo Min; Hsu, Allen; Lee, Yi-Hsien; Dresselhaus, Mildred; Palacios, Tomás; Kim, Ki Kang; Kong, Jing

    2013-09-01

    Copper foil is the most common substrate to synthesize monolayer graphene by chemical vapor deposition (CVD). The surface morphology and conditions of the copper foil can be very different depending on the various suppliers or different batches. These surface properties of copper strongly affect the growth behavior of graphene, thus rendering the growth conditions irreproducible when different batches of Cu foil are used. Furthermore, the quality of the graphene is severely affected as well. In this work, we report a facile method of copper pre-cleaning to improve the graphene quality and the reproducibility of the growth process. We found that the commercial Ni etchant (based on nitric acid) or nitric acid is the most effective cleaning agent among various acidic or basic solutions. The graphene grown on thus-treated copper surfaces is very clean and mostly monolayer when observed under scanning electron microscopy (SEM) and optical imaging, as compared to the graphene grown on untreated copper foil. Different batches (but with the same catalog number) of copper foil from Alfa Aesar Company were examined to explore the effect of copper pre-cleaning; consistent growth results were obtained when pre-cleaning was used. This method overcomes a commonly encountered problem in graphene growth and could become one of the standard protocols for preparing the copper foil substrate for growing graphene or other 2D materials.

  18. Hot Firing of a Full Scale Copper Tubular Combustion Chamber

    National Research Council Canada - National Science Library

    Cooley, C

    2002-01-01

    .... The AEC copper tubular design combines high material thermal conductivity and large effective surface area in a structurally compliant coolant channel configuration to achieve significant heat pick...

  19. Preparation of single-crystal copper ferrite nanorods and nanodisks

    International Nuclear Information System (INIS)

    Du Jimin; Liu Zhimin; Wu Weize; Li Zhonghao; Han Buxing; Huang Ying

    2005-01-01

    This article, for the first time, reports the preparation of single-crystal copper ferrite nanorods and nanodisks. Using amorphous copper ferrite nanoparticles synthesized by reverse micelle as reaction precursor, single-crystal copper ferrite nanorods were synthesized via hydrothermal method in the presence of surfactant polyethylene glycol (PEG), however, copper ferrite nanodisks were prepared through the same procedures except the surfactant PEG. The resulting nanomaterials have been characterized by powder X-ray diffraction (XRD), selected electron area diffraction (SEAD), and transmission electron microscopy (TEM). The bulk composition of the samples was determined by means of X-ray photoelectron spectroscopy (XPS)

  20. A Case of Isolated Elevated Copper Levels during Pregnancy

    Directory of Open Access Journals (Sweden)

    LaToya R. Walker

    2011-01-01

    Full Text Available Introduction. Outside of Wilson's Disease, abnormal copper metabolism is a rare condition. In pregnancy, excess copper levels can be associated with intrauterine growth restriction, preeclampsia and neurological disease. Case Report. A 32 year old Gravida 4 para 2012 with an obstetrical history complicated by elevated copper levels presented for routine prenatal care. Her children had elevated copper levels at birth, with her firstborn child being diagnosed with autism and suffering three myocardial infarctions and being treated for elevated copper levels. During her prior pregnancies, she declined treatment for her elevated copper levels. During this pregnancy, she had declined chelation therapy and instead choose zinc therapy. She delivered a healthy infant with normal copper levels. Conclusion. Alterations in copper metabolism are rare, the consequences in pregnancy can be devastating. While isolated elevations of copper in pregnancy is exceedingly rare, it is treated the same as Wilson's disease. The goal is to prevent fetal growth restricting and neurological sequelae in the newborn and preeclampsia in the mother. Counseling, along with treatment options and timely delivery can greatly improve neonatal and maternal outcome.

  1. Final report on characterization of physical and mechanical properties of copper and copper alloys before and after irradiation

    DEFF Research Database (Denmark)

    Singh, B.N.; Tähtinen, S.

    2002-01-01

    The present report summarizes and highlights the main results of the work carried out during the last 5-6 years on effects of neutron irradiation on physical and mechanical properties of copper and copper alloys. The work was an European contribution toITER Research and Development programme...... the suitability of a copper alloy for its use in the first wall and divertor components of ITER. It is pointed out that the present work has managed onlyto identify some of the critical problems and limitations of the copper alloys for their employment in the hostile environment of 14 MeV neutrons. A considerable...

  2. Study on copper kinetics in processing sulphide ore mixed with copper and zinc with sulfuric acid leaching under pressure

    Science.gov (United States)

    Wen-bo, LUO; Ji-kun, WANG; Yin, GAN

    2018-01-01

    Sulphide ore mixed with copper and zinc is processed with pressure acid leaching. Research is conducted on the copper kinetic. The stirring rate is set at 600 rpm which could eliminate the influence of external diffusions. Research is conducted on the factors affecting the copper leaching kinetic are temperature, pressure, concentration of sulfuric acid, particle size. The result shows that the apparent activity energy is 50.7 KJ/mol. We could determine that the copper leaching process is shrinking core model of chemical reaction control and work out the leaching equation.

  3. 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.

  4. 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 (environmental impact. CMP is a costly process due to its huge consumption of pure water and slurry. Additionally, Cu-CMP processing generates a waste stream containing certain amounts of copper and abrasive slurry particles. In this study, the separation technique electrocoagulation was investigated to remove both copper and abrasive slurry particles simultaneously. For effluent containing ˜40 ppm 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.

  5. 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

  6. 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.

  7. Hollow silica-copper-carbon anodes using copper metal-organic frameworks as skeletons.

    Science.gov (United States)

    Sun, Zixu; Xin, Fengxia; Cao, Can; Zhao, Chongchong; Shen, Cai; Han, Wei-Qiang

    2015-12-28

    Hollow silica-copper-carbon (H-SCC) nanocomposites are first synthesized using copper metal-organic frameworks as skeletons to form Cu-MOF@SiO(2) and then subjected to heat treatment. In the composites, the hollow structure and the void space from the collapse of the MOF skeleton can accommodate the huge volume change, buffer the mechanical stress caused by lithium ion insertion/extraction and maintain the structural integrity of the electrode and a long cycling stability. The ultrafine copper with a uniform size of around 5 nm and carbon with homogeneous distribution from the decomposition of the MOF skeleton can not only enhance the electrical conductivity of the composite and preserve the structural and interfacial stabilization, but also suppress the aggregation of silica nanoparticles and cushion the volume change. In consequence, the resulting material as an anode for lithium-ion batteries (LIBs) delivers a reversible capacity of 495 mA h g(-1) after 400 cycles at a current density of 500 mA g(-1). The synthetic method presented in this paper provides a facile and low-cost strategy for the large-scale production of hollow silica/copper/carbon nanocomposites as an anode in LIBs.

  8. 2-Organoselenomethyl-1H-benzimidazole Complexes of Copper(II) and Copper(I)

    Czech Academy of Sciences Publication Activity Database

    Leboschka, M.; Sieger, M.; Sarkar, B.; Heck, J.; Niemeyer, M.; Bubrin, D.; Lissner, F.; Schleid, T.; Záliš, Stanislav; Su, Ch. Y.; Kaim, W.

    2009-01-01

    Roč. 635, 13-14 (2009), s. 2177-2184 ISSN 0044-2313 R&D Projects: GA MŠk OC 139; GA AV ČR KAN100400702 Institutional research plan: CEZ:AV0Z40400503 Keywords : coordination models * copper * imidazole ligands * selenoether ligands Subject RIV: CG - Electrochemistry Impact factor: 1.226, year: 2009

  9. Aspects of energy reduction by autogenous copper production in the copper smelting plant Bor

    International Nuclear Information System (INIS)

    Najdenov, Ivan; Raić, Karlo T.; Kokeza, Gordana

    2012-01-01

    This work presents a comparative analysis of the energy consumption during copper production by the “standard” procedure (roasting in a fluo–solid reactor and smelting in a reverberatory furnace) in the Smelting Plant in Bor with modern autogenous procedures. All forms of expended energy were reduced to primary energy or to the same energy form, i.e., to the energy equivalent of the process (EEP), the raw material and the process materials. In addition, the energy equivalent of the process and waste products (water vapour, thermal energy and similar) were balanced. To complete the consumption of all energy generating products in copper production, they were reduced to conditional fuel (coal equivalent = 29.3 MJ/kg). Additionally, this study suggests replacement of the existing technology by an appropriate autogenous procedure and considers the prospects for further development of mining and metallurgy in Bor. Estimates of development perspectives for copper production should be comprehensive, based on complete and relevant data, as well as on real considerations of future development in world production. -- Highlights: ► “Standard” autogenous copper production in the Smelting Plant, Bor, Serbia. ► Comparation of energy consumption in “standard” with other autogenous procedures. ► All forms of energy are reduced to energy equivalent and conditional fuel. ► Replacement of existing technology with the appropriate autogenous procedure. ► Perspectives of further development of mining and metallurgy in Bor.

  10. Ring structures and copper mineralization in Kerman porphyry copper belt, SE Iran

    Directory of Open Access Journals (Sweden)

    Gholamreza Mirzababaei

    2012-10-01

    Full Text Available The role of some ring structures in the distribution of porphyry copper deposits in south Kerman porphyry copper belt is discussed. In the study area, ring structures are circular or elliptical shaped features which are partly recognized on satellite images. In this study, Landsat multispectral images were used to identify ring structures in the area. The rudimentary identification stages of the circles were mainly based on their circular characteristics on the images. These structures match with the regional tectonic features and can be seen mainly in two types; namely, large-magnitude and small scale circles. The associated mineralization in the study area is mainly porphyry Cu and vein type base metal sulfide deposits. There is a sensible relationship between the large circles and mineralization. These circles have encompassed almost entire Cu deposits and prospects in south part of Kerman porphyry copper belt. The small circles seem to be external traces of (porphyritic intrusive bodies that appear on surface as small circles. Formation of the large circular structures do not appear to be related to the external processes and there is no clear indication of how they came into existence but, their arrangement around the edges of a positive residual anomaly area shows the probable role of this anomaly in their formation. This matter is also recognized on the generalized crustal thickness map of the region in which an updoming of the upper mantle is observed. This study can improve our collective knowledge for copper exploration in this region.

  11. Preparation of copper and silicon/copper powders by a gas ...

    Indian Academy of Sciences (India)

    Administrator

    carrier gas and precipitated as spherical Cu metal and Si/Cu composite powders. The mean diameter of the resulting powder was 100–200 nm. Keywords. Copper powder; Si/Cu composite particle; gas evaporation–condensation method; characteriza- tion. 1. ... important role in electronics, catalysts, resins, and ther-.

  12. A copper complex (2,2¢-bipyridine)(salicyclideneglycinato) copper(II ...

    Indian Academy of Sciences (India)

    Administrator

    coordinated to 3 histidine residues in the equatorial position and two water molecules giving a CuN3O2 coordination sphere. In this paper, we report a copper(II) complex having a CuN3O2 coordination geometry which is found to be catalytically active in oxidising ascorbic acid in air. In aqueous–methanol, ascorbic acid ...

  13. Serum levels of copper, zinc and copper-to-zinc ratio in subjects with ...

    African Journals Online (AJOL)

    Abnormal levels of essential elements often occur in patients with hypertension due to genetic, environmental causes and drug use in the management of the disease. This study seeks to evaluate serum levels of copper, zinc and calculated Cu/Zn ratio in subjects with hypertension who were on different types of drugs.

  14. Seeding of silicon by copper ion implantation for selective electroless copper plating

    Energy Technology Data Exchange (ETDEWEB)

    Bhansali, S.; Sood, D.K.; Zmood, R.B. [Microelectronic and Materials Technology Centre, Royal Melbourne Institute of Technolgy, Melbourne, VIC (Australia)

    1993-12-31

    We report on the successful use of copper(self) ion implantation into silicon to seed the electroless plating of copper on silicon (100) surfaces. Copper ions have been implanted to doses of 5E14-6.4E16 ions/cm{sup 2} using a MEEVA ion implanter at extraction voltage of 40kV. Dose was varied in fine steps to determine the threshold dose of 2E15 Cu ions/cm{sup 2} for `seed` formation of copper films on silicon using a commercial electroless plating solution. Plated films were studied with Rutherford backscattering spectrometry, scanning electron microscopy, EDX and profilometry . The adhesion of films was measured by `scotch tape test`. The adhesion was found to improve with increasing dose. However thicker films exhibited rather poor adhesion and high internal stress. SEM results show that the films grow first as isolated islands which become larger and eventually impinge into a continuous film as the plating time is increased. (authors). 5 refs., 1 tab., 3 figs.

  15. Creep in ODS copper reinforced with alumina short fibres - DRS copper

    Czech Academy of Sciences Publication Activity Database

    Kuchařová, Květa; Zhu, S. J.; Čadek, Josef

    2003-01-01

    Roč. 355, 1-2 (2003), s. 267-276 ISSN 0921-5093 R&D Projects: GA AV ČR IBS2041001 Institutional research plan: CEZ:AV0Z2041904 Keywords : Creep * ODS copper * Load transfer Subject RIV: JI - Composite Materials Impact factor: 1.365, year: 2003

  16. The Copper(I) / Copper(II) Transition in Complexes with 8-alkylthioquinoline Based Multidentate Ligands

    Czech Academy of Sciences Publication Activity Database

    Su, Ch. Y.; Liao, S.; Wanner, M.; Fiedler, Jan; Zhang, Ch.; Kang, B. S.; Kaim, W.

    - (2003), s. 189-202 ISSN 1472-7773 R&D Projects: GA MŠk OC D15.10 Institutional research plan: CEZ:AV0Z4040901 Keywords : X-ray structure * 5-coordinate copper(II) complexes * electron-transfer kinetics Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.023, year: 2002

  17. Bioleaching of copper from old flotation tailings samples (Copper Mine Bor, Serbia

    Directory of Open Access Journals (Sweden)

    Stanković Srđan

    2015-01-01

    Full Text Available Bioleaching of samples taken from depths of 10, 15, and 20 meters from old flotation tailings of the Copper Mine Bor was conducted in shaken flasks using extremely acidic water of Lake Robuleas lixiviant. Yield of copper after five weeks of the bioleaching experiment was 68.34±1.21% for 15 m sample, 72.57±0.57% for 20 m sample and 97.78±5.50% for 10 m sample. The obtained results were compared to the results of acid leaching of the same samples and it was concluded that bioleaching was generally more efficient for the treatment of samples taken from depths of 10 m and 20 m. The content of pyrite in the 20 m sample, which contained the highest amount of this mineral, was reduced after bioleaching. Benefits of this approach are: recovery of substantial amounts of copper, reducing the environmental impact of flotation tailings and the application of abundant and free water from the Robule acidic lake as lixiviant. Results of the experiment showed that bioleaching can be more efficient than acid leaching for copper extraction from flotation tailings with higher sulfide contents. [Projekat Ministarstva nauke Republike Srbije, br. 176016 i br. 173048

  18. 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.

  19. Computer simulation of replacement sequences in copper

    International Nuclear Information System (INIS)

    Schiffgens, J.O.; Schwartz, D.W.; Ariyasu, R.G.; Cascadden, S.E.

    1978-01-01

    Results of computer simulations of , , and replacement sequences in copper are presented, including displacement thresholds, focusing energies, energy losses per replacement, and replacement sequence lengths. These parameters are tabulated for six interatomic potentials and shown to vary in a systematic way with potential stiffness and range. Comparisons of results from calculations made with ADDES, a quasi-dynamical code, and COMENT, a dynamical code, show excellent agreement, demonstrating that the former can be calibrated and used satisfactorily in the analysis of low energy displacement cascades. Upper limits on , , and replacement sequences were found to be approximately 10, approximately 30, and approximately 14 replacements, respectively. (author)

  20. 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)

  1. Guided design of copper oxysulfide superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Yee, Chuck-Hou; Birol, Turan; Kotliar, Gabriel

    2015-07-01

    We describe a framework for designing novel materials, combining modern first-principles electronic-structure tools, materials databases, and evolutionary algorithms capable of exploring large configurational spaces. Guided by the chemical principles introduced by Antipov et al., for the design and synthesis of the Hg-based high-temperature superconductors, we apply our framework to screen 333 proposed compositions to design a new layered copper oxysulfide, Hg(CaS)2CuO2. We evaluate the prospects of superconductivity in this oxysulfide using theories based on charge-transfer energies, orbital distillation and uniaxial strain.

  2. Copper vapor laser development for SILVA

    Science.gov (United States)

    Bettinger, Antoine; Neu, M.; Maury, J.; Chatelet, Jacques A.

    1993-05-01

    The recent developments of the components for high power Copper Vapor Laser (CVL) have been oriented towards four main goals: high quality laser beam, mainly for the CVL oscillators, increase of the extracted energy out of the amplifying stage, fully integrated and monolithic design for oscillator and amplifier, and extended lifetime and high reliability. A first step of this work, which is done under contract with CILAS (Compagnie Industrielle des Lasers) led to an injection seeded oscillator and a 100 Watt amplifier; the present step concerns development of a 400 Watts class amplifier.

  3. Anodization of Copper in Chloride Media

    Science.gov (United States)

    1994-01-31

    in various media. In chloride-containing solution, seawater for example, the cuprous species CuCI and CuCl2" are major products of copper anodization...assumption was used in these determinations, which rendered only the foot of the voltammetric wave useful for calculating 132, and the formation of CuCI was...time-independent, and refers to steady-state currents at given potentials. In the present case of the formation of CuCI and CuCl2 , we are interested in

  4. Corrosion of copper and copper alloys in a basaltic repository environment

    International Nuclear Information System (INIS)

    Brehm, W.F.

    1990-01-01

    Corrosion testing done on copper and copper alloys in support of the basalt repository program is discussed. Tests were performed under anoxic conditions at 50C, 100C, 150C and 200C in the presence of a saturated basalt-bentonite packing. Tests were also performed in an air/steam mixture at temperatures between 150C and 200C. Some tests, particularly those in air/steam mixtures, were done in the presence of radiation fields of 10 2 , 10 3 or 10 4 rad/h. Exposure periods were up to 28 months. A synthetic groundwater, Grande Ronde ≠4, was used. The materials studied were ASTM B402μm·a for copper and 17 μm·a for cupronickel, but the average rates were muμm·a was obtained. The rates at longer times were less than a third of this value. Corrosion increased monotonically with time and temperature. Chalcocite (Cu 2 S) was the corrosion product at 200C. There was no detectable radiation effect, and no pitting was observed. In air/steam corrosion was uniform with no pitting. Linear corrosion was observed for pure copper. The maximum corrosion penetration after 25 months was 0.13 mm at 300C; cupronickel corroded more slowly, with a maximum penetration of 0.045mm after 25 months. Cuprite (Cu 2 O) and tenorite (CuO) were identified on cupronickel, but only Cu 2 O on copper. A pronounced radiation effect was seen at 250C, but not at 150C; the surface film morphology was different under irradiation. In the short term the presence of packing increased the corrosion rate. 5 refs

  5. Selection of fecal enterococci exhibiting tcrB-mediated copper resistance in pigs fed diets supplemented with copper.

    Science.gov (United States)

    Amachawadi, R G; Shelton, N W; Shi, X; Vinasco, J; Dritz, S S; Tokach, M D; Nelssen, J L; Scott, H M; Nagaraja, T G

    2011-08-15

    Copper, as copper sulfate, is increasingly used as an alternative to in-feed antibiotics for growth promotion in weaned piglets. Acquired copper resistance, conferred by a plasmid-borne, transferable copper resistance (tcrB) gene, has been reported in Enterococcus faecium and E. faecalis. A longitudinal field study was undertaken to determine the relationship between copper supplementation and the prevalence of tcrB-positive enterococci in piglets. The study was done with weaned piglets, housed in 10 pens with 6 piglets per pen, fed diets supplemented with a normal (16.5 ppm; control) or an elevated (125 ppm) level of copper. Fecal samples were randomly collected from three piglets per pen on days 0, 14, 28, and 42 and plated on M-Enterococcus agar, and three enterococcal isolates were obtained from each sample. The overall prevalence of tcrB-positive enterococci was 21.1% (38/180) in piglets fed elevated copper and 2.8% (5/180) in the control. Among the 43 tcrB-positive isolates, 35 were E. faecium and 8 were E. faecalis. The mean MICs of copper for tcrB-negative and tcrB-positive enterococci were 6.2 and 22.2 mM, respectively. The restriction digestion of the genomic DNA of E. faecium or E. faecalis with S1 nuclease yielded a band of ∼194-kbp size to which both tcrB and the erm(B) gene probes hybridized. A conjugation assay demonstrated cotransfer of tcrB and erm(B) genes between E. faecium and E. faecalis strains. The higher prevalence of tcrB-positive enterococci in piglets fed elevated copper compared to that in piglets fed normal copper suggests that supplementation of copper in swine diets selected for resistance.

  6. Biovailability of copper and zinc in pig and cattle slurries

    NARCIS (Netherlands)

    Jakubus, M.; Dach, J.; Starmans, D.A.J.

    2013-01-01

    Slurry is an important source of macronutrients, micro-nutrients and organic matter. Despite the considerable fertilizer value of slurry, it may be abundant in amounts of copper and zinc originating from dietary. The study presents quantitative changes in copper and zinc in individual slurries (pig

  7. Material testing of copper by extrusion-cutting

    DEFF Research Database (Denmark)

    Segalina, F.; De Chiffre, Leonardo

    2017-01-01

    was developed and implemented on a CNC lathe. An investigation was carried out extrusion-cutting copper discs using high-speed-steel cutting tools at 100 m/min cutting speed. Flow stress values for copper under machining-relevant conditions were obtained from measurement of the extrusion-cutting force...

  8. Screening for childhood anaemia using copper sulphate densitometry

    African Journals Online (AJOL)

    Screening for childhood anaemia using copper sulphate densitometry. M Funk, T Hambrock, G C van Niekerk, D F Wittenberg. Abstract. Objective. To evaluate copper sulphate densitometry to screen for childhood anaemia in a primary care setting, with a view to identifying children requiring definitive diagnostic testing and ...

  9. Synthesis and structure of copper(II) complexes: Potential cyanide ...

    Indian Academy of Sciences (India)

    ing the oxidase models. The necessity to make progress in developing copper oxidase models requires synthesis of appropriate copper complexes to rationalize the func- tions of such oxidases unequivocally.46–52 Therefore, to study the coordination chemistry of Cu(II) incorpo- rating the new azo ligands,53 HLa and HLb, ...

  10. Organically associated copper in Mandovi and Zuari estuaries

    Digital Repository Service at National Institute of Oceanography (India)

    George, M.D.; Sawkar, K.

    Studies were conducted to determine the extent to which copper is associated with organic matter in the estuarine and riverine waters of Mandovi and Zuari. It was observed that in the Mandovi the organically associated copper varies between 0 and 46...

  11. Photocleavage of DNA by copper(II) complexes

    Indian Academy of Sciences (India)

    The chemistry of ternary and binary copper(II) complexes showing efficient visible lightinduced DNA cleavage activity is summarized in this article. The role of the metal in photo-induced DNA cleavage reactions is explored by designing complex molecules having a variety of ligands. Ternary copper(II) complexes with amino ...

  12. Synthesis, Characterization and DNA Cleavage of Copper(II ...

    African Journals Online (AJOL)

    Purpose: To study deoxyribonucleic acid (DNA) shearing capability of copper(II) complex of dithiothreitol (DTT) and to fevaluate its potential application in cancer therapy. Methods: A parrot green complex was synthesized by grinding copper acetate monohydrate and DTT in 1:2 molar ratio in a mortar until no fumes of acetic ...

  13. Photocleavage of DNA by copper(II) complexes

    Indian Academy of Sciences (India)

    Abstract. The chemistry of ternary and binary copper(II) complexes showing efficient visible light- induced DNA cleavage activity is summarized in this article. The role of the metal in photo-induced. DNA cleavage reactions is explored by designing complex molecules having a variety of ligands. Ternary copper(II) complexes ...

  14. Mixed-ligand binuclear copper (II) complex of 5 ...

    Indian Academy of Sciences (India)

    A new mixed-ligand binuclear copper(II) complex [Cu(MS)(bpy)]2.(ClO4)2, built of 5-methylsalicylaldehyde and 2,2'-bipyridyl has been synthesized and characterized by using elemental analysis, IR and UV-Vis spectroscopy. Crystal structure of the complex shows that copper(II) ion lies in a square pyramidal coordination ...

  15. Preparation and Characterization of Directionally Freeze-cast Copper Foams

    Directory of Open Access Journals (Sweden)

    Aurelia I. Cuba Ramos

    2012-08-01

    Full Text Available Because of their excellent thermal and electric conductivities, copper foams are ideally suited for applications such as heat exchangers, catalyst supports and EMI-shields. Here, we demonstrate the preparation of copper with ~80% aligned, elongated, interconnected pores via directional freeze casting, a well established processing technique for porous ceramics. First, an aqueous slurry of 40−80 nm cupric oxide powders was directionally solidified, resulting in a preform consisting of elongated, aligned dendrites of pure ice separated by interdendritic ice walls with high oxide powder content. Oxide rather than metallic nanometric particles are used, as the latter would oxidize rapidly and uncontrollably when suspended in the aqueous solution used during directional casting. The preforms were then freeze-dried to sublimate the ice and sintered in a hydrogen-bearing atmosphere to reduce the copper oxide to metallic copper particles and densify these copper particles. Microstructural analysis of the copper foams shows that three types of porosities are present: (i aligned, elongated pores replicating the ice dendrites created during the freeze-casting process; (ii micro-porosity in the partially sintered copper walls separating the elongated pores; and (iii cracks in these copper walls, probably created because of shrinkage associated with the reduction of the oxide powders.

  16. Etching of Copper Coated Mylar Tubes With CF-4 Gas

    International Nuclear Information System (INIS)

    Ecklund, Karl M.; Hartman, Keith W.; Hebert, Michael J.; Wojcicki, Stanley G.

    1996-01-01

    Using 5 mm diameter copper coated mylar straw tubes at a potential of 2.30 KV relative to a concentric 20 (mu)m diameter gold-plated tungsten anode, it has been observed that with very low flow rates of CF4-based gases the conductive copper cathode material may be removed entirely from the mylar surface

  17. Functional recovery of biofilm bacterial communities after copper exposure.

    NARCIS (Netherlands)

    Boivin, Marie-Elène Y; Massieux, Boris; Breure, Anton M; Greve, Gerdit D; Rutgers, Michiel; Admiraal, Wim

    2006-01-01

    Potential of bacterial communities in biofilms to recover after copper exposure was investigated. Biofilms grown outdoor in shallow water on glass dishes were exposed in the laboratory to 0.6, 2.1, 6.8 micromol/l copper amended surface water and a reference and subsequently to un-amended surface

  18. Detoxification of copper fungicide using EDTA-modified cellulosic ...

    African Journals Online (AJOL)

    Pesticides are poisons and can be particularly dangerous when misused or carelessly disposed. The detoxification of a copper fungicide (KOCIDE 101) using maize cob, a cellulosic material, was studied. Based on copper as the active agent (after a sorption period of 1 h), the concentration of the fungicide reduced from an ...

  19. The use of biodegradable polymers for the stabilization of copper ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 40; Issue 5. The use of biodegradable polymers for the stabilization of copper nanoparticles synthesized by chemical reduction method. ALI OLAD MAHNAZ ... However, agglomerated copper nanoparticles were obtained bythis chemical reduction method. Hence, the ...

  20. Tolerance of Serpula lacrymans to copper-based wood preservatives

    Science.gov (United States)

    Anne Christine Steenkjaer Hastrup; Frederick Green; Carol A. Clausen; Bo Jensen

    2005-01-01

    Serpula lacrymans, the dry rot fungus, is considered the most economically important wood decay fungus in certain temperate regions of the world, namely northern Europe, Japan, and Australia. Previously, copper-based wood preservatives were commonly used for pressure treatment of wood for building construction, but some decay fungi are known to be copper tolerant. In...

  1. Assessment of the Secondary Copper Reserves of Nations.

    Science.gov (United States)

    Maung, Kyaw Nyunt; Hashimoto, Seiji; Mizukami, Mizuki; Morozumi, Masataka; Lwin, Cherry Myo

    2017-04-04

    The sustainable use of metals demands consideration not only of primary metals in the natural environment but also of secondary metals in society as alternative resources. This study applied our proposed classification framework of secondary resources to copper (1) to investigate the applicability of the framework and (2) to assess the secondary copper reserves and resources of selected countries. To estimate secondary copper reserves, we introduced the variable "secondary reserve ratio": the fraction of in-use copper stocks that is technically and economically recoverable. Our estimates showed that the United States and China have secondary copper reserves of 44 and 33 Mt, respectively, and showed that global secondary copper reserves are about 30% of global primary reserves. The application of the classification framework showed that considerable amounts of secondary copper resources are in landfills, which are potential targets of future extraction of secondary copper through landfill mining. Overall, the classification framework provides a better understanding of the current size of available secondary resources and waste deposits. It also highlights the need for integrated management of primary and secondary resources.

  2. Thermal and IR studies on copper doped polyvinyl alcohol

    Indian Academy of Sciences (India)

    TECS

    polymer films were prepared by casting process. Thermal transitions and thermal degradation of samples with respect to copper concentration were studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. Increase in glass transition temperature as a function of copper ...

  3. Temporal aspects of copper homeostasis and its crosstalk with hormones

    Directory of Open Access Journals (Sweden)

    Lola ePeñarrubia

    2015-04-01

    Full Text Available To cope with the dual nature of copper as being essential and toxic for cells, plants temporarily adapt the expression of copper homeostasis components to assure its delivery to cuproproteins while avoiding the interference of potential oxidative damage derived from both copper uptake and photosynthetic reactions during light hours. The circadian clock participates in the temporal organization of coordination of plant nutrition adapting metabolic responses to the daily oscillations. This timely control improves plant fitness and reproduction and holds biotechnological potential to drive increased crop yields. Hormonal pathways, including those of abscisic acid, gibberellins, ethylene, auxins, and jasmonates are also under direct clock and light control, both in mono and dicotyledons. In this review, we focus on copper transport in Arabidopsis thaliana and Oryza sativa and the presumable role of hormones in metal homeostasis matching nutrient availability to growth requirements and preventing metal toxicity. The presence of putative hormone-dependent regulatory elements in the promoters of copper transporters genes suggests hormonal regulation to match special copper requirements during plant development. Spatial and temporal processes that can be affected by hormones include the regulation of copper uptake into roots, intracellular trafficking and compartmentalisation, and long-distance transport to developing vegetative and reproductive tissues. In turn, hormone biosynthesis and signalling are also influenced by copper availability, which suggests reciprocal regulation subjected to temporal control by the central oscillator of the circadian clock. This transcriptional regulatory network, coordinates environmental and hormonal signalling with developmental pathways to allow enhanced micronutrient acquisition efficiency.

  4. The effect of copper on some laboratory indices of Clarias ...

    African Journals Online (AJOL)

    fish to copper in water, at concentrations above 1.0mg CuSO4/g elicits adverse haematological responses and causes homeostatic imbalance. To prevent pollution, it is expedient that there be regulation of the amount of copper sulphate used in cocoa farms, as occurs in south western Nigeria. Key words: Clarias gariepinus ...

  5. Experimental investigation of industrial copper deformed by wire ...

    African Journals Online (AJOL)

    drawing on microstructure and physical properties of industrial copper wires. Copper wires were provided by E.N.I.CA.Biskra (Algeria). We investigated some wires with different strain levels (as received, 1.20, 2.10, and ε = 3.35).

  6. Efficient alkyne homocoupling catalysed by copper immobilized on functionalized silica

    NARCIS (Netherlands)

    van Gelderen, L.; Rothenberg, G.; Calderone, V.R.; Wilson, K.; Shiju, N.R.

    2013-01-01

    Copper immobilized on a functionalized silica support is a good catalyst for the homocoupling of terminal alkynes. The so-called Glaser-Hay coupling reaction can be run in air with catalytic amounts of base. The copper catalyst is active for multiple substituted alkynes, in both polar and non-polar

  7. Efficacy of copper borax preservative against wood decay

    Science.gov (United States)

    William Abbott; Bessie Woodward; Michael West

    2001-01-01

    In this study, a wood preservative containing active ingredients of 43.5% borax and 3.1% copper hydroxide was evaluated in soil-block tests in accordance with AWPA E10. Results suggested thatthe copper hydroxide was not contributing to fungal toxicity at preservative threshold levels. Thresholds determined for this preservative were very close to those previously...

  8. Copper nanoparticles as an alternative feed additives in poultry diet

    DEFF Research Database (Denmark)

    Scott, A.; Vadalasetty, K. P.; Chwalibog, A.

    2018-01-01

    Copper is a vital trace element involved in various physiological and biochemical processes. However, animals can only absorb a small fraction of copper and the most is excreted, contaminating soil and aquatic environment. Hence the use of this mineral as a growth promoter is today one of the cru...

  9. Effect of dietary organic and inorganic copper supplement on ...

    African Journals Online (AJOL)

    The effect of dietary copper source and dosage on growth, apparent nutrient digestibility, trace mineral retention, ileal morphology and blood parameters of cockerel chicks were investigated using two hundred and forty (240) day-old chicks arranged in a 2 × 3 factorial arrangements involving 2 Cu sources (copper sulphate ...

  10. solution growth and characterization of copper oxide thin films ...

    African Journals Online (AJOL)

    Thin films of copper oxide (CuO) were grown on glass slides by using the solution growth technique. Copper cloride (CuCl ) and potassium telluride (K T O ) were used. Buffer 2 2e 3 solution was used as complexing agent. The solid state properties and optical properties were obtained from characterization done using PYE ...

  11. Effect of aging on copper nanoparticles synthesized by pulsed laser ...

    Indian Academy of Sciences (India)

    Administrator

    2009-06-23

    Jun 23, 2009 ... Effect of aging on copper nanoparticles in water. 1365. Figure 1. (a) UV-Visible absorption spectrum of as synthesized colloidal solution of nanoparticles by laser ablation of copper in water, (b) UV-Visible absorption spectra of colloidal nanoparticles recorded with aging of 6 alternate days and (c) Tauc plot ...

  12. Phase Planning for Overall Copper-Fiber Switch-over

    DEFF Research Database (Denmark)

    Gutierrez Lopez, Jose Manuel; Jensen, Michael; Andreasen, Morten Henius

    2013-01-01

    This paper introduces a phase planning concept to the imminent copper-fiber switch-over action. Traditional copper loops are to be replaced by modern fiber lines in order to keep up with the current evolution of data communications. This work proposes two novel approaches of how to schedule...

  13. Synthesis, stereochemistry and antimicrobial activity of copper(II ...

    African Journals Online (AJOL)

    On the basis of the analytical data, magnetic moments and spectral data, a square-planar geometry has been proposed for the nickel(II) and copper(II) complexes with these ligands. Some representative complexes of copper(II) and nickel(II) were found to have remarkable antifungal and antibacterial activity. KEY WORDS: ...

  14. Effects of Copper Exchange Levels on Complexation of Ammonia in ...

    African Journals Online (AJOL)

    Above five copper atoms per unit cell, the major complex becomes [Cu(NH3)4]2+ and it is least interacting with the zeolite framework walls. The [Cu(NH3)4]2+ complex which was formed at higher copper levels per unit cell was most favoured by the presence of maximal amount of ammonia. Keywords: Cation Exchange ...

  15. 7 CFR 1755.403 - Copper cable telecommunications plant measurements.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false Copper cable telecommunications plant measurements... UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE TELECOMMUNICATIONS POLICIES ON SPECIFICATIONS, ACCEPTABLE MATERIALS, AND STANDARD CONTRACT FORMS § 1755.403 Copper cable telecommunications plant measurements. (a...

  16. Sensitivity and specificity of copper sulphate test in determining ...

    African Journals Online (AJOL)

    Background: The accuracy of the copper sulphate method for the rapid screening of prospective blood donors has been questioned because this rapid screening method may lead to false deferral of truly eligible prospective blood donors. Objective: This study was aimed at determining the sensitivity and specificity of copper ...

  17. Nano copper ferrite: A reusable catalyst for the synthesis of , ...

    Indian Academy of Sciences (India)

    Copper ferrite nano material as reusable heterogeneous initiator in the synthesis of , -unsaturated ketones and allylation to acid chlorides are presented. The reaction of allylichalides with various acid chlorides is achieved in the presence of copper ferrite nano powders at room temperature in tetrahydrofuran (THF).

  18. Retained copper sleeve of cu-T IUCD

    African Journals Online (AJOL)

    Dr Adaji

    Case Report. A 47-year old para 7+1 five alive presented at the. Reproductive Health center for removal of a copper-T intrauterine contraceptive device following a clinical diagnosis of pelvic inflammatory disease. The device was inserted the previous year. After easy removal , it was observed that the copper sleeve on one ...

  19. The safety of copper sulfate to channel catfish eggs

    Science.gov (United States)

    Copper sulfate (CuSO4) is an economical treatment to control fungus (Saprolegnia spp.) on channel catfish eggs and is widely used by the industry. The purpose of this study was to determine the safety of copper sulfate to channel catfish eggs when treated at the therapeutic rate (10 mg/L), and also...

  20. Salicylaldimine Copper(II) complex catalyst: Pioneer for ring ...

    Indian Academy of Sciences (India)

    copper(II) solution with one molar equivalent of salicylaldimine Schiff-base ligand in methanol under nitrogen atmosphere. .... Here we report the synthe- sis and use of tetra-coordinated salicylaldimine copper complex in L-lactide polymerization. This complex is stable in air and easy to prepare. In addition, the steric.

  1. Development of copper bromide laser master oscillator power ...

    Indian Academy of Sciences (India)

    2014-02-09

    Feb 9, 2014 ... Development of master oscillator power amplifier (MOPA) system of copper bromide laser (CBL) operating at 110 W average power is reported. The spectral distribution of power at green (510.6 nm) and yellow (578.2 nm) components in the output of a copper bromide laser is studied as a function of ...

  2. ( Momordica balsamina Linn.) Leaf Extract on Copper Corrosion in

    African Journals Online (AJOL)

    Inhibition of copper corrosion in acidic medium by ethanolic extract of Momordica balsamina leaves was investigated. Findings reveal that the rate of copper corrosion increases with increasing temperature of the medium but decreases as the concentration of the Momordica balsamina extract added to the medium ...

  3. Iodometric determination of copper and iron in one solution

    NARCIS (Netherlands)

    Agterdenbos, J.; Tellingen, E.J. v.

    CopperII and ironIII may be titrated iodometrically in a single solution. Copper is titrated first, iron being masked with fluoride. After the end-point is reached, aluminium chloride is added to de-mask the iron, which is titrated after some minutes. Good results are obtained.

  4. Synthesis, Characterization and Antimicrobial Activity of Copper(II ...

    African Journals Online (AJOL)

    This study presents the synthesis, characterization and antimicrobial activity of copper(II) complexes of some ortho-substituted aniline Schiff bases (L1–L8). The Schiff bases and their respective copper(II) complexes were characterized by a combination of elemental analysis, infrared and UV/Visible studies. The structures of ...

  5. New canine models of copper toxicosis: diagnosis, treatment, and genetics

    NARCIS (Netherlands)

    Fieten, H.; Penning, L.C.; Leegwater, P.A.J.; Rothuizen, J.

    The One Health principle recognizes that human health, animal health, and environmental health are inextricably linked. An excellent example is the study of naturally occurring copper toxicosis in dogs to help understand human disorders of copper metabolism. Besides the Bedlington terrier, where

  6. Copper-associated chronic hepatitis in the Labrador retriever

    NARCIS (Netherlands)

    Hoffmann, G.

    2008-01-01

    This thesis describes copper-associated chronic hepatitis as a new disease in the Labrador. A study of 143 dogs that were prospectively assessed for clinical parameters, laboratory results, and liver copper concentrations, as well as histologic signs of inflammation revealed that more than two

  7. Uptake and distribution of copper in the freshwater crab ...

    African Journals Online (AJOL)

    ... between the two localities. P. perlatus may therefore still be utilized in biomonitoring studies, not necessarily to reflect prevailing environmental concentrations, since copper can also be regulated, but to assess exposure to and bioavailibility of copper. Key words: heavy metal accumulation, digestive gland, biomonitoring.

  8. Copper is an endogenous modulator of neural circuit spontaneous activity.

    Science.gov (United States)

    Dodani, Sheel C; Firl, Alana; Chan, Jefferson; Nam, Christine I; Aron, Allegra T; Onak, Carl S; Ramos-Torres, Karla M; Paek, Jaeho; Webster, Corey M; Feller, Marla B; Chang, Christopher J

    2014-11-18

    For reasons that remain insufficiently understood, the brain requires among the highest levels of metals in the body for normal function. The traditional paradigm for this organ and others is that fluxes of alkali and alkaline earth metals are required for signaling, but transition metals are maintained in static, tightly bound reservoirs for metabolism and protection against oxidative stress. Here we show that copper is an endogenous modulator of spontaneous activity, a property of functional neural circuitry. Using Copper Fluor-3 (CF3), a new fluorescent Cu(+) sensor for one- and two-photon imaging, we show that neurons and neural tissue maintain basal stores of loosely bound copper that can be attenuated by chelation, which define a labile copper pool. Targeted disruption of these labile copper stores by acute chelation or genetic knockdown of the CTR1 (copper transporter 1) copper channel alters the spatiotemporal properties of spontaneous activity in developing hippocampal and retinal circuits. The data identify an essential role for copper neuronal function and suggest broader contributions of this transition metal to cell signaling.

  9. Preparation of ultrafine grained copper nanoparticles via immersion deposit method

    Science.gov (United States)

    Abbasi-Kesbi, Fatemeh; Rashidi, Ali Mohammad; Astinchap, Bandar

    2018-03-01

    Today, the exploration about synthesis of nanoparticles is much of interest to materials scientists. In this work, copper nanoparticles have been successfully synthesized by immersion deposit method in the absence of any stabilizing and reducing agents. Copper (II) sulfate pentahydrate as precursor salt and distilled water and Ethylene glycol as solvents were used. The copper nanoparticles were deposited on plates of low carbon steel. The effects of copper sulfate concentrations and solvent type were investigated. X-ray diffraction, scanning electron microscopy and UV-Visible spectroscopy were taken to investigate the crystallite size, crystal structure, and morphology and size distribution and the growth process of the nanoparticles of obtained Cu particles. The results indicated that the immersion deposit method is a particularly suitable method for synthesis of semispherical copper nanoparticles with the crystallites size in the range of 22 to 37 nm. By increasing the molar concentration of copper sulfate in distilled water solvent from 0.04 to 0.2 M, the average particles size is increased from 57 to 81 nm. The better size distribution of Cu nanoparticles was achieved using a lower concentration of copper sulfate. By increasing the molar concentration of copper sulfate in water solvent from 0.04 to 0.2, the location of the SPR peak has shifted from 600 to 630 nm. The finer Cu nanoparticles were formed using ethylene glycol instead water as a solvent. Also, the agglomeration and overlapping of nanoparticles in ethylene glycol were less than that of water solvent.

  10. Electrical and magnetic properties of new copper arylcarboxylates

    Science.gov (United States)

    Cueto, Senida; Rys, Paul; Rys, Franz S.; Sanjinez, Rosendo; Peter Straumann, Hans

    1992-02-01

    The magnetic and electrical properties of new copper arylcarboxylates are presented. Special emphasis on copper(II) terephthalate trihydrate (CuTT) is given, and the magnetic and electrical properties are correlated with the crystal structure, recently determined by us. We have obtained new conductor materials by partial reduction of CuTT. The properties of these new compounds are discussed.

  11. Removal of copper and cobalt from aqueous solutions using natural ...

    African Journals Online (AJOL)

    Synthetic non-mixed sulphate solutions of copper and cobalt recorded maximum cation uptakes of 79% and 63% with 0.02 M HCl-activated clinoptilolite respectively. From the Cu/Co mixed solutions, both cobalt and copper recorded a 79% uptake with 0.02 M HCl-activation. The 0.04 M HCl activation gave percentage ...

  12. Characterization of copper resistant ciliates: Potential candidates for ...

    African Journals Online (AJOL)

    The ciliate protists tolerate elevated concentrations of metals, which are accumulated, bound to metallothioneins (MTs) peculiar to these organisms. Copper is one of such contaminant found in the wastewater of local industries. The concentrations of copper which caused 50% reduction (LC50) in the cell population of ...

  13. Surface plasmon effect in nanocrystalline copper/DLC composite ...

    Indian Academy of Sciences (India)

    Composite films of nanocrystalline copper embedded in DLC matrix prepared by electrodeposition technique were studied for their optical properties. Particle size and metal volume fractions were tailored by varying the amount of copper containing salt in the electrolyte. Blue-shift of the surface plasmon resonance peak in ...

  14. Biochemical characterization of the human copper transporter Ctr1.

    Science.gov (United States)

    Lee, Jaekwon; Peña, Maria Marjorette O; Nose, Yasuhiro; Thiele, Dennis J

    2002-02-08

    The trace metal copper is an essential cofactor for a number of biological processes including mitochondrial oxidative phosphorylation, free radical detoxification, neurotransmitter synthesis and maturation, and iron metabolism. Consequently, copper transport at the cell surface and the delivery of copper to intracellular proteins are critical events in normal physiology. Little is known about the molecules and biochemical mechanisms responsible for copper uptake at the plasma membrane in mammals. Here, we demonstrate that human Ctr1 (hCtr1) is a component of the copper transport machinery at the plasma membrane. hCtr1 transports copper with high affinity in a time-dependent and saturable manner and is metal-specific. hCtr1-mediated (64)Cu transport is an energy-independent process and is stimulated by extracellular acidic pH and high K(+) concentrations. hCtr1 exists as a homomultimer at the plasma membrane in mammalian cells. This is the first report on the biochemical characterization of the human copper transporter hCtr1, which is important for understanding mechanisms for mammalian copper transport at the plasma membrane.

  15. THE INFLUENCE OF DIETARY SULPHUR ON COPPER ANT ...

    African Journals Online (AJOL)

    Sulphur, copper, molybdenum, sheep). (Sleutelwoorde: Sw,awel .... Treatments, average Cu and Mo intakelsheeplday during the experiment and average S intakeslsheeplday during the different stoges of the trial. Copper. Molybdenum. Sulphur ..... mav escape ruminal degradation and not participate jn the interactions with ...

  16. Biochemical characterization of P-type copper ATPases

    Science.gov (United States)

    Inesi, Giuseppe; Pilankatta, Rajendra; Tadini-Buoninsegni, Francesco

    2014-01-01

    Copper ATPases, in analogy with other members of the P-ATPase superfamily, contain a catalytic headpiece including an aspartate residue reacting with ATP to form a phosphoenzyme intermediate, and transmembrane helices containing cation-binding sites [TMBS (transmembrane metal-binding sites)] for catalytic activation and cation translocation. Following phosphoenzyme formation by utilization of ATP, bound copper undergoes displacement from the TMBS to the lumenal membrane surface, with no H+ exchange. Although PII-type ATPases sustain active transport of alkali/alkali-earth ions (i.e. Na+, Ca2+) against electrochemical gradients across defined membranes, PIB-type ATPases transfer transition metal ions (i.e. Cu+) from delivery to acceptor proteins and, prominently in mammalian cells, undergo trafficking from/to various membrane compartments. A specific component of copper ATPases is the NMBD (N-terminal metal-binding domain), containing up to six copper-binding sites in mammalian (ATP7A and ATP7B) enzymes. Copper occupancy of NMBD sites and interaction with the ATPase headpiece are required for catalytic activation. Furthermore, in the presence of copper, the NMBD allows interaction with protein kinase D, yielding phosphorylation of serine residues, ATP7B trafficking and protection from proteasome degradation. A specific feature of ATP7A is glycosylation and stabilization on plasma membranes. Cisplatin, a platinum-containing anti-cancer drug, binds to copper sites of ATP7A and ATP7B, and undergoes vectorial displacement in analogy with copper. PMID:25242165

  17. Green synthesis of copper oxide nanoparticles using Abutilon ...

    African Journals Online (AJOL)

    Purpose: To synthesize copper oxide (CuO) nanoparticles using a ecofriendly technique and evaluate their antimicrobial, antioxidant and photo-catalytic dye degradation potentials. Methods: A superficial method (solution combustion method) was employed for the synthesis of copper oxide nanoparticles from an aqueous ...

  18. Development of copper bromide laser master oscillator power

    Indian Academy of Sciences (India)

    2014-02-09

    Feb 9, 2014 ... Development of master oscillator power amplifier (MOPA) system of copper bromide laser (CBL) operating at 110 W average power is reported. The spectral distribution of power at green (510.6 nm) and yellow (578.2 nm) components in the output of a copper bromide laser is studied as a function of ...

  19. Development of copper bromide laser master oscillator power ...

    Indian Academy of Sciences (India)

    2014-02-09

    Feb 9, 2014 ... Abstract. Development of master oscillator power amplifier (MOPA) system of copper bromide laser (CBL) operating at 110 W average power is reported. The spectral distribution of power at green (510.6 nm) and yellow (578.2 nm) components in the output of a copper bromide laser is studied as a function ...

  20. Preconcentration and extraction of copper(II) on activated carbon ...

    African Journals Online (AJOL)

    Activated carbon modified method was used for the preconcentration and determination of copper content in real samples such as tap water, wastewater and a synthetic water sample by flame atomic absorption spectrometry. The copper(II) was adsorbed quantitatively on activated carbon due to its complexation with ...

  1. Thermodynamic investigation of the MOCVD of copper films from bis ...

    Indian Academy of Sciences (India)

    Equilibrium concentrations of various condensed and gaseous phases have been thermodynamically calculated, using the free energy minimization criterion, for the metalorganic chemical vapour deposition (MOCVD) of copper films using bis(2,2,6,6-tetramethyl-3,5-heptadionato)copper(II) as the precursor material.

  2. Polyurethane nanofibers containing copper nanoparticles as future materials

    DEFF Research Database (Denmark)

    Sheikh, Faheem A.; Kanjwal, Muzafar Ahmed; Saran, Saurabh

    2011-01-01

    In the present study, we aimed to represent a novel approach to fabricate polyurethane nanofibers containing copper nanoparticles (NPs) by simple electrospinning process. A simple method, not depending on additional foreign chemicals, has been employed to utilize prepared copper NPs in polyurethane...

  3. Effect of Chronic Dietary Copper Exposure on Haematology and ...

    African Journals Online (AJOL)

    Michael Horsfall

    Effect of Chronic Dietary Copper Exposure..... AJANI, E K; AKPOILIH, B U parameters by rainbow trout (Oncorhynchus mykiss) during chronic dietary exposure to copper. Aquat. Toxicol. 47: 23 – 41. Heath, A.G. (1995). Water pollution and fish physiology. CRC Press, Boca Ration, Florida,. USA. Pp. 56-78. Jain, N.S (1986).

  4. Potentiating effect of ecofriendly synthesis of copper oxide ...

    Indian Academy of Sciences (India)

    which suggests that copper nanoparticles synthesized from. Tritium aestivum exhibited similar inhibition activity with the maximum zone of 18 mm for Aspergillus niger. Like- wise, minimum inhibition activity by Aspergillus flavus was. 9 mm zone [23]. The cytotoxicity of the copper nanoparticles was evalu- ated against MCF-7 ...

  5. Influence of diethyldithiocarbamate on cadmium and copper toxicity ...

    African Journals Online (AJOL)

    drinie

    Daphnia magna. Environ. Technol. Lett. 5 109-120. ROBERT W (1984) The toxicity and bioaccumulation of cadmium and copper as affected by humic acid. Aquat. Toxicol. 5 267-274. WHITTON B and SHEHATA F (1982) Influence of cobalt, nickel, copper and cadmium on blue green alga Anacystis nidulans. Environ. Pollut.

  6. Effect of surface etching and electrodeposition of copper on nitinol

    Science.gov (United States)

    Ramos-Moore, E.; Rosenkranz, A.; Matamala, L. F.; Videla, A.; Durán, A.; Ramos-Grez, J.

    2017-10-01

    Nitinol-based materials are very promising for medical and dental applications since those materials can combine shape memory, corrosion resistance, biocompatibility and antibacterial properties. In particular, surface modifications and coating deposition can be used to tailor and to unify those properties. We report preliminary results on the study of the effect of surface etching and electrodeposition of Copper on Nitinol using optical, chemical and thermal techniques. The results show that surface etching enhances the surface roughness of Nitinol, induces the formation of Copper-based compounds at the Nitinol-Copper interface, reduces the austenitic-martensitic transformations enthalpies and reduces the Copper coating roughness. Further studies are needed in order to highlight the influence of the electrodeposited Copper on the memory shape properties of NiTi.

  7. The copper-silver occurrences of Rahmani, Western Sahara, Algeria

    Science.gov (United States)

    Fuchs, Y.; Arbey, F.; Bouima, T.

    1996-05-01

    The copper-silver occurrences of Rahmani (Western Sahara, Algeria) are located in paleochannel facies of Cambrian sandstones deposited on Pan-African volcanics and intrusives. Sulfur isotope analyses were performed on pyrite and copper sulfides in order to trace the origin of the copper-silver mineralization. S isotopic data preclude that bacterial reduction of Cambrian sulfate could have induced the formation of the sulfides. Non-bacterial reduction of sulfate during burial diagenesis is the most valuable explanation for disseminated pyrite. Isotopic ratios on copper sulfides indicate that they result from the reaction of actual or subactual sulfate-bearing surface water with the disseminated pyrite. The origin of copper and silver remains unclear. They are thought to be brought by the downward migrating surface water but their origin could be either the leaching of the Cambrian sandstones or of the weathered volcanics.

  8. Studies in pitting corrosion on archaeological bronzes. Copper

    International Nuclear Information System (INIS)

    Bresle, Aa.; Saers, J.; Arrhenius, B.

    1983-01-01

    Copper has been proposed as a canister material for use in the long-term storage of radioactive waste from nuclear power reactors. The storage period has been set to at least 100 000 years, during which time the copper cylinders must remain intact so that the contained waste has no possibility of leaking out. In this work, the pitting factor in archaelogical copper objects have been determined. The absolute values of the pitting factor obtained are generally very low. In the case of the most thoroughly studied material the pitting factor is only slightly more than three units. Nor does the native copper, with a presumed burial period of about 8000 years, exhibit particularly high values. In summary, it can therefore be concluded that the present study does not provide support for the assumption of extremely high pitting factors in copper-base material that has been buried for periods of several millenia. (G.B.)

  9. Influence of copper on Euplotes sp. and associated bacterial population

    Directory of Open Access Journals (Sweden)

    Guilherme Oliveira Andrade da Silva

    2014-05-01

    Full Text Available The influence of copper on the ciliate Euplotes sp. and associated bacteria isolated from sediment samples of Guanabara Bay were investigated in bioassays. This region is highly affected by heavy metals such as copper, from solid waste constantly dumped in the bay and other sources such as industrial effluents, antifouling paints, atmospheric deposition and urban drainage, and even today there are few data on the metal toxicity to the ecosystem of the Bay of Guanabara. Bioassays were conducted to estimate the LC50-24 h of copper, in order to determine the concentration of metal bearing 50% of the population mortality. The results indicated that the concentrations of 0.05 and 0.009 mg L-1 presented no toxicity to Euplotes sp. The associated bacteria are tolerant to copper concentrations used in bioassays, and suggest that they could be used as a potential agent in the bioremediation of areas affected by copper.

  10. Additive and Photochemical Manufacturing of Copper

    Science.gov (United States)

    Yung, Winco K. C.; Sun, Bo; Meng, Zhengong; Huang, Junfeng; Jin, Yingdi; Choy, Hang Shan; Cai, Zhixiang; Li, Guijun; Ho, Cheuk Lam; Yang, Jinlong; Wong, Wai Yeung

    2016-12-01

    In recent years, 3D printing technologies have been extensively developed, enabling rapid prototyping from a conceptual design to an actual product. However, additive manufacturing of metals in the existing technologies is still cost-intensive and time-consuming. Herein a novel platform for low-cost additive manufacturing is introduced by simultaneously combining the laser-induced forward transfer (LIFT) method with photochemical reaction. Using acrylonitrile butadiene styrene (ABS) polymer as the sacrificial layer, sufficient ejection momentum can be generated in the LIFT method. A low-cost continuous wave (CW) laser diode at 405 nm was utilized and proved to be able to transfer the photochemically synthesized copper onto the target substrate. The wavelength-dependent photochemical behaviour in the LIFT method was verified and characterized by both theoretical and experimental studies compared to 1064 nm fiber laser. The conductivity of the synthesized copper patterns could be enhanced using post electroless plating while retaining the designed pattern shapes. Prototypes of electronic circuits were accordingly built and demonstrated for powering up LEDs. Apart from pristine PDMS materials with low surface energies, the proposed method can simultaneously perform laser-induced forward transfer and photochemical synthesis of metals, starting from their metal oxide forms, onto various target substrates such as polyimide, glass and thermoplastics.

  11. Bioremediation of copper stressed Trigonella foenum graecum

    Directory of Open Access Journals (Sweden)

    Awatif A. Mohsen

    2013-11-01

    Full Text Available Copper is one of the heavy metals, although it is an essential microelement through interference with numerous physiological processes, when it absorbed in excess amounts, it can be toxic and induce a number of deleterious effects. A pot experiment was conducted in order to assess the possible effects of Nostoc muscorum (2 g/ kg soil fresh pellets on the growth and some metabolic activities of Trigonella foenum gracum at 30 and 60 days of growth growing under copper stress. This experimental plant was grown in clay-sandy soil (2:1 W/W amended either with different concentrations of CuSO4 (0.4, 0.6, 0.8 and 1.0 g/kg soil or Nostoc mixed with Cu (0.6, 0.8 and 1.0 g/kg soil. Application of Nostoc in a mixture with Cu significantly increased fresh and dry weight of root and shoot, photosynthetic pigments and ctivity at 30 and 60 days of growth when compared with their counterparts of Cu treatment. In addition, the content of K+, Ca2+, P3+ and iron were increased with the exception of a decrease in Cu level at 60 days of growth. On the other hand, the content of starch was significantly decreased at 30 and 60 days of growth. Moreover, the activity of both peroxidase (POD and superoxide dismutase (SOD were reduced by applying Nostoc to the soil having different concentrations of Cu.

  12. The corrosion of copper in compacted clay

    Energy Technology Data Exchange (ETDEWEB)

    King, F.; Ryan, S.R.; Litke, C.D

    1997-12-01

    The uniform corrosion behaviour of copper has been investigated in the presence of compacted clay under simulated disposal vault conditions. The compacted clay is used to simulate the buffer material that would surround copper nuclear fuel waste containers in a Canadian disposal vault. The effect of the speciation of dissolved Cu has been investigated using three synthetic groundwaters of different salinity and various dissolved [O{sub 2}]. The formation of cuprous species is favoured by low [O{sub 2}] and high [C1{sup -}], with Cu(II) species formed at high [O{sub 2}] and low [C1{sup -}]. Because the Na-bentonite clay is a cation-exchange material, positively charged Cu(II) species are found to adsorb more strongly than negatively charged CuC1{sup -} complexes. The impact of the Cu speciation on four experimental parameters is reported: the corrosion rate, the interfacial [Cu] in the clay, the [Cu] profile through the clay layer, and the Cu(l):Cu(ll) ratio in the precipitated corrosion products. In agreement with previous studies, the overall rate-controlling process is believed to be the diffusion of dissolved Cu away from the corroding surface. Adsorption acts as a driving force for corrosion by immobilizing dissolved Cu. Under the conditions used in these experiments, the diffusion of dissolved O{sub 2} to the Cu surface was not rate controlling. (author)

  13. Niobium Titanium and Copper wire samples

    CERN Multimedia

    2009-01-01

    Two wire samples, both for carrying 13'000Amperes. I sample is copper. The other is the Niobium Titanium wiring used in the LHC magnets. The high magnetic fields needed for guiding particles around the Large Hadron Collider (LHC) ring are created by passing 12’500 amps of current through coils of superconducting wiring. At very low temperatures, superconductors have no electrical resistance and therefore no power loss. The LHC is the largest superconducting installation ever built. The magnetic field must also be extremely uniform. This means the current flowing in the coils has to be very precisely controlled. Indeed, nowhere before has such precision been achieved at such high currents. Magnet coils are made of copper-clad niobium–titanium cables — each wire in the cable consists of 9’000 niobium–titanium filaments ten times finer than a hair. The cables carry up to 12’500 amps and must withstand enormous electromagnetic forces. At full field, the force on one metre of magnet is comparable ...

  14. Brazing Inconel 625 Using the Copper Foil

    Science.gov (United States)

    Chen, Wen-Shiang; Wang, Cheng-Yen; Shiue, Ren-Kae

    2013-12-01

    Brazing Inconel 625 (IN-625) using the copper foil has been investigated in this research. The brazed joint is composed of nanosized CrNi3 precipitates and Cr/Mo/Nb/Ni quaternary compound in the Cu/Ni-rich matrix. The copper filler 50 μm in thickness is enough for the joint filling. However, the application of Cu foil 100 μm in thickness has little effect on the shear strength of the brazed joint. The specimen brazed at 1433 K (1160 °C) for 1800 seconds demonstrates the best shear strength of 470 MPa, and its fractograph is dominated by ductile dimple fracture with sliding marks. Decreasing the brazing temperature slightly decreases the shear strength of the brazed joint due to the presence of a few isolated solidification shrinkage voids smaller than 15 μm. Increasing the brazing temperature, especially for the specimen brazed at 1473 K (1200 °C), significantly deteriorates the shear strength of the joint below 260 MPa because of coalescence of isothermal solidification shrinkage voids in the joint. The Cu foil demonstrates potential in brazing IN-625 for industrial application.

  15. Mechanisms of copper ion mediated Huntington's disease progression.

    Directory of Open Access Journals (Sweden)

    Jonathan H Fox

    2007-03-01

    Full Text Available Huntington's disease (HD is caused by a dominant polyglutamine expansion within the N-terminus of huntingtin protein and results in oxidative stress, energetic insufficiency and striatal degeneration. Copper and iron are increased in the striata of HD patients, but the role of these metals in HD pathogenesis is unknown. We found, using inductively-coupled-plasma mass spectroscopy, that elevations of copper and iron found in human HD brain are reiterated in the brains of affected HD transgenic mice. Increased brain copper correlated with decreased levels of the copper export protein, amyloid precursor protein. We hypothesized that increased amounts of copper bound to low affinity sites could contribute to pro-oxidant activities and neurodegeneration. We focused on two proteins: huntingtin, because of its centrality to HD, and lactate dehydrogenase (LDH, because of its documented sensitivity to copper, necessity for normoxic brain energy metabolism and evidence for altered lactate metabolism in HD brain. The first 171 amino acids of wild-type huntingtin, and its glutamine expanded mutant form, interacted with copper, but not iron. N171 reduced Cu(2+in vitro in a 1:1 copper:protein stoichiometry indicating that this fragment is very redox active. Further, copper promoted and metal chelation inhibited aggregation of cell-free huntingtin. We found decreased LDH activity, but not protein, and increased lactate levels in HD transgenic mouse brain. The LDH inhibitor oxamate resulted in neurodegeneration when delivered intra-striatially to healthy mice, indicating that LDH inhibition is relevant to neurodegeneration in HD. Our findings support a role of pro-oxidant copper-protein interactions in HD progression and offer a novel target for pharmacotherapeutics.

  16. Role of copper in regression of cardiac hypertrophy.

    Science.gov (United States)

    Zheng, Lily; Han, Pengfei; Liu, Jiaming; Li, Rui; Yin, Wen; Wang, Tao; Zhang, Wenjing; Kang, Y James

    2015-04-01

    Pressure overload causes an accumulation of homocysteine in the heart, which is accompanied by copper depletion through the formation of copper-homocysteine complexes and the excretion of the complexes. Copper supplementation recovers cytochrome c oxidase (CCO) activity and promotes myocardial angiogenesis, along with the regression of cardiac hypertrophy and the recovery of cardiac contractile function. Increased copper availability is responsible for the recovery of CCO activity. Copper promoted expression of angiogenesis factors including vascular endothelial growth factor (VEGF) in endothelial cells is responsible for angiogenesis. VEGF receptor-2 (VEGFR-2) is critical for hypertrophic growth of cardiomyocytes and VEGFR-1 is essential for the regression of cardiomyocyte hypertrophy. Copper, through promoting VEGF production and suppressing VEGFR-2, switches the VEGF signaling pathway from VEGFR-2-dependent to VEGFR-1-dependent, leading to the regression of cardiomyocyte hypertrophy. Copper is also required for hypoxia-inducible factor-1 (HIF-1) transcriptional activity, acting on the interaction between HIF-1 and the hypoxia responsible element and the formation of HIF-1 transcriptional complex by inhibiting the factor inhibiting HIF-1. Therefore, therapeutic targets for copper supplementation-induced regression of cardiac hypertrophy include: (1) the recovery of copper availability for CCO and other critical cellular events; (2) the activation of HIF-1 transcriptional complex leading to the promotion of angiogenesis in the endothelial cells by VEGF and other factors; (3) the activation of VEGFR-1-dependent regression signaling pathway in the cardiomyocytes; and (4) the inhibition of VEGFR-2 through post-translational regulation in the hypertrophic cardiomyocytes. Future studies should focus on target-specific delivery of copper for the development of clinical application. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. The future of copper in China--A perspective based on analysis of copper flows and stocks.

    Science.gov (United States)

    Zhang, Ling; Cai, Zhijian; Yang, Jiameng; Yuan, Zengwei; Chen, Yan

    2015-12-01

    This study attempts to speculate on the future of copper metabolism in China based on dynamic substance flow analysis. Based on tremendous growth of copper consumption over the past 63 years, China will depict a substantially increasing trend of copper in-use stocks for the next 30 years. The highest peak will be possibly achieved in 2050, with the maximum ranging between 163 Mt and 171 Mt. After that, total stocks are expected to slowly decline 147-154 Mt by the year 2080. Owing to the increasing demand of in-use stocks, China will continue to have a profound impact on global copper consumption with its high import dependence until around 2020, and the peak demand for imported copper are expected to approach 5.5 Mt/year. Thereafter, old scrap generated by domestic society will occupy an increasingly important role in copper supply. In around 2060, approximately 80% of copper resources could come from domestic recycling of old scrap, implying a major shift from primary production to secondary production. With regard to the effect of lifetime distribution uncertainties in different end-use sectors of copper stocks on the predict results, uncertainty evaluation was performed and found the model was relatively robust to these changes. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Effects of a copper tolerant grass (Agrostis capillaris) on the ecosystem of a copper-contaminated arable soil

    NARCIS (Netherlands)

    Boon, G.T.; Bouwman, L.A.; Bloem, J.; Römkens, P.F.A.M.

    1998-01-01

    To test how a dysfunctioning ecosystem of a severely metal-polluted soil responds to renewed plant growth, a pot experiment was conducted with soil from an experimental arable field with pH and copper gradients imposed 13 years ago. In this experimentfour pH/copper combinations from this field were

  19. Concentration of copper in muscles, liver, hair and feaces of growing rabbits fed diet supplemented with copper sulphate

    Czech Academy of Sciences Publication Activity Database

    Marounek, Milan; Skřivanová, V.; Volek, Z.; Březina, P.

    2002-01-01

    Roč. 10, č. 4 (2002), s. 167-170 ISSN 1257-5011 R&D Projects: GA AV ČR KSK5020115 Grant - others:GA NATO(XX) MO2-99-04 Keywords : copper retention * mineral metabolism * copper supplementation Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition

  20. Environmental concentrations of copper, chromium, and arsenic released from a chromated-copper-arsenate-(CCA-C-) treated wetland boardwalk

    Science.gov (United States)

    Stan T. Lebow; Daniel Foster

    2005-01-01

    A study was conducted to evaluate environmental accumulation and mobility of total copper, chromium, and arsenic adjacent to a chromated-copper-arsenate-(CCA-C-) treated wetland boardwalk. The study was considered a severe test because it included a large volume of treated wood in a site with high annual rainfall. Soil and sediment samples were collected before...

  1. A copper-induced quinone degradation pathway provides protection against combined copper/quinone stress in Lactococcus lactis IL1403.

    Science.gov (United States)

    Mancini, Stefano; Abicht, Helge K; Gonskikh, Yulia; Solioz, Marc

    2015-02-01

    Quinones are ubiquitous in the environment. They occur naturally but are also in widespread use in human and industrial activities. Quinones alone are relatively benign to bacteria, but in combination with copper, they become toxic by a mechanism that leads to intracellular thiol depletion. Here, it was shown that the yahCD-yaiAB operon of Lactococcus lactis IL1403 provides resistance to combined copper/quinone stress. The operon is under the control of CopR, which also regulates expression of the copRZA copper resistance operon as well as other L. lactis genes. Expression of the yahCD-yaiAB operon is induced by copper but not by quinones. Two of the proteins encoded by the operon appear to play key roles in alleviating quinone/copper stress: YaiB is a flavoprotein that converts p-benzoquinones to less toxic hydroquinones, using reduced nicotinamide adenine dinucleotide phosphate (NADPH) as reductant; YaiA is a hydroquinone dioxygenase that converts hydroquinone putatively to 4-hydroxymuconic semialdehyde in an oxygen-consuming reaction. Hydroquinone and methylhydroquinone are both substrates of YaiA. Deletion of yaiB causes increased sensitivity of L. lactis to quinones and complete growth arrest under combined quinone and copper stress. Copper induction of the yahCD-yaiAB operon offers protection to copper/quinone toxicity and could provide a growth advantage to L. lactis in some environments. © 2014 John Wiley & Sons Ltd.

  2. Determination of HCl and VOC Emission from Thermal Degradation of PVC in the Absence and Presence of Copper, Copper(II) Oxide and Copper(II) Chloride

    OpenAIRE

    Jafari, Ahamad J.; Donaldson, John D.

    2009-01-01

    Polyvinyl chloride (PVC) has played a key role in the development of the plastic industry over the past 40 years. Thermal degradation of PVC leads to formation of many toxic pollutants such as HCl, aromatic and volatile organic carbon vapors. Thermal degradation of PVC and PVC in the present of copper, cupric oxide and copper(II) chloride were investigated in this study using a laboratory scale electrical furnace. HCl and Cl- ion were analyzed by a Dionex ion chromatograph and VOCs compounds ...

  3. Evaluation of copper, aluminum bronze, and copper-nickel container material for the Yucca mountain project

    International Nuclear Information System (INIS)

    Kass, J.

    1990-01-01

    Copper, 70 percent aluminum bronze, and 70/30 copper-nickel were evaluated as potential waste-packaging materials as part of the Yucca Mountain Project. The proposed waste repository site is under a desert mountain in southern Nevada. The expected temperatures at the container surface are higher than at other sites, about 250C at the beginning of the containment period; they could fall below the boiling point of water during this period, but will be exposed to very little water, probably less than 5 l/a. Initial gamma flux will be 10 4 rad/h, and no significant hydrostatic or lithostatic pressure is expected. Packages will contain PWR or BWR fuel, or processed-glass waste. Three copper alloys are being considered for containers: oxygen-free copper (CDA 102); 7 percent aluminum bronze (CDA 613); and 70/30 copper-nickel (CDA 715). Phase separation due to prolonged thermal exposure could be a problem for the two alloys, causing embrittlement. The reduction of internal oxides present in pure copper by hydrogen could cause mechanical degradation. Corrosion and oxidation rates measured for the three materials in well water with and without gamma irradiation at flux rates about ten times higher than those expected were all quite small. The corrosion/oxidation rates for CDA715 show a marked increase under irradiation, but are still acceptable. In the presence of ammonia and other nitrogen-bearing species stress corrosion cracking (SCC) is a concern. Welded U-bend specimens of all three materials have been tested for up to 10000 h in highly irradiated environments, showing no SCC. There was some alloy segregation in the Al bronze specimens. The investigators believe that corrosion and mechanical properties will not present problems for these materials at this site. Further work is needed in the areas of weld inspection, welding techniques, embrittlement of weld metal, the effects of dropping the containers during emplacement, and stress corrosion cracking. Other materials

  4. Role of plastic deformation in wear of copper and copper - 10-percent-aluminum alloy in cryogenic fuels

    Science.gov (United States)

    Bill, R. C.; Wisander, D. W.

    1973-01-01

    High-purity copper specimens and a copper-aluminum (10%) alloy specimen were subjected to sliding against Type 440 C in cryogenic fuel environments. It was found that virtually all wear occurred by the plastic deformation of a recrystallized layer extending to about 10 micrometers below the wear scar surface of the copper or copper alloy. The wear debris was in the form of a layered structure adhering to the exit region of the wear scar. Measurements on the high purity copper specimens indicated that the wear rate was proportional to the applied load and to the sliding velocity squared. A physical model of the wear process is proposed to account for these observations.

  5. Comparative proteomic analysis of the molecular responses of mouse macrophages to titanium dioxide and copper oxide nanoparticles unravels some toxic mechanisms for copper oxide nanoparticles in macrophages.

    Directory of Open Access Journals (Sweden)

    Sarah Triboulet

    Full Text Available Titanium dioxide and copper oxide nanoparticles are more and more widely used because of their catalytic properties, of their light absorbing properties (titanium dioxide or of their biocidal properties (copper oxide, increasing the risk of adverse health effects. In this frame, the responses of mouse macrophages were studied. Both proteomic and targeted analyses were performed to investigate several parameters, such as phagocytic capacity, cytokine release, copper release, and response at sub toxic doses. Besides titanium dioxide and copper oxide nanoparticles, copper ions were used as controls. We also showed that the overall copper release in the cell does not explain per se the toxicity observed with copper oxide nanoparticles. In addition, both copper ion and copper oxide nanoparticles, but not titanium oxide, induced DNA strands breaks in macrophages. As to functional responses, the phagocytic capacity was not hampered by any of the treatments at non-toxic doses, while copper ion decreased the lipopolysaccharide-induced cytokine and nitric oxide productions. The proteomic analyses highlighted very few changes induced by titanium dioxide nanoparticles, but an induction of heme oxygenase, an increase of glutathione synthesis and a decrease of tetrahydrobiopterin in response to copper oxide nanoparticles. Subsequent targeted analyses demonstrated that the increase in glutathione biosynthesis and the induction of heme oxygenase (e.g. by lovastatin/monacolin K are critical for macrophages to survive a copper challenge, and that the intermediates of the catecholamine pathway induce a strong cross toxicity with copper oxide nanoparticles and copper ions.

  6. Comparative proteomic analysis of the molecular responses of mouse macrophages to titanium dioxide and copper oxide nanoparticles unravels some toxic mechanisms for copper oxide nanoparticles in macrophages.

    Science.gov (United States)

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

    2015-01-01

    Titanium dioxide and copper oxide nanoparticles are more and more widely used because of their catalytic properties, of their light absorbing properties (titanium dioxide) or of their biocidal properties (copper oxide), increasing the risk of adverse health effects. In this frame, the responses of mouse macrophages were studied. Both proteomic and targeted analyses were performed to investigate several parameters, such as phagocytic capacity, cytokine release, copper release, and response at sub toxic doses. Besides titanium dioxide and copper oxide nanoparticles, copper ions were used as controls. We also showed that the overall copper release in the cell does not explain per se the toxicity observed with copper oxide nanoparticles. In addition, both copper ion and copper oxide nanoparticles, but not titanium oxide, induced DNA strands breaks in macrophages. As to functional responses, the phagocytic capacity was not hampered by any of the treatments at non-toxic doses, while copper ion decreased the lipopolysaccharide-induced cytokine and nitric oxide productions. The proteomic analyses highlighted very few changes induced by titanium dioxide nanoparticles, but an induction of heme oxygenase, an increase of glutathione synthesis and a decrease of tetrahydrobiopterin in response to copper oxide nanoparticles. Subsequent targeted analyses demonstrated that the increase in glutathione biosynthesis and the induction of heme oxygenase (e.g. by lovastatin/monacolin K) are critical for macrophages to survive a copper challenge, and that the intermediates of the catecholamine pathway induce a strong cross toxicity with copper oxide nanoparticles and copper ions.

  7. Erythrocyte copper chaperone for superoxide dismutase is increased following marginal copper deficiency in adult and postweanling mice.

    Science.gov (United States)

    Lassi, Katie C; Prohaska, Joseph R

    2012-02-01

    A sensitive and reliable biomarker has yet to be identified for marginal copper deficiency in humans. The need for such a biomarker is critical, because increased cases of human copper deficiency evolve following bariatric surgery and other secondary factors besides diet. Four experiments were devised to induce marginal copper deficiency through copper-deficient (CuD) diets (5 wk for mice and 4 wk for rats). In Expt. 1 and 2, male postweanling mice were raised in either solid-bottom plastic cages (Expt. 1) or stainless steel hanging cages (Expt. 2) and compared. Postweanling rats (Expt. 3) and adult mice (Expt. 4) were also studied using stainless steel cages. Copper-adequate controls were fed a semipurified diet containing 9 mg Cu/kg. CuD rats exhibited the most severe changes in biomarkers due to copper limitation, including major reductions in plasma ceruloplasmin (Cp) and erythrocyte superoxide dismutase (Sod1) and augmentation in copper chaperone for Sod1 (CCS). The CuD mice in Expt. 2 were more deficient than the CuD mice in Expt. 1, likely due to coprophagia differences. In fact, the CuD mice in Expt. 1 had unaltered Sod1 or Cp levels. Importantly though, these marginally deficient mice and CuD adult mice that had no changes in Cp activity or liver copper level had robust augmentation of CCS. Erythrocyte CCS was the only consistent biomarker to change in copper deficiency for all dietary groups, suggesting that CCS may be an excellent biomarker for human confirmation of marginal copper deficiency.

  8. Effects of a copper-tolerant grass (Agrostis capillaris) on the ecosystem of a copper-contaminated arable soil

    Energy Technology Data Exchange (ETDEWEB)

    Boon, G.T. [State Univ. Groningen (Netherlands); Bouwman, L.A.; Bloem, J.; Roemkens, P.F.A.M. [Research Inst. for Agrobiology and Soil Fertility, Haren (Netherlands)

    1998-10-01

    To test how a dysfunctioning ecosystem of a severely metal-polluted soil responds to renewed plant growth, a pot experiment was conducted with soil from an experimental arable field with pH and copper gradients imposed 13 years ago. In this experiment, four pH/copper combinations from this field were either planted with a pH- and copper-resistant grass cultivar or remained fallow. During a 10-week period, the dynamics of the microbial activity and of the abundances of bacteria, protozoa. and nematodes were measured, as were the dynamics of several chemical soil parameters. After 13 years of copper, which had resulted in severely reduced crop growth, no effects were observed on bacterial numbers, respiration, or protozoan numbers, but bacterial growth was strongly reduced in the low pH plots, and even more so in low pH plots enriched with copper. Of the organisms, only nematodes were negatively affected under conditions of high copper load at low pH. In these plots, numbers belonging to all feeding categories were strongly reduced. Planting of a copper-tolerant grass variety, Agrostis capillaris L. var. Parys Mountain, resulted within 10 weeks in faster bacterial growth and more protozoa and bacterivorous nematodes in comparison with fallow controls; these effects were markedly strongest in the acidic, copper-enriched soils. During incubation, fungivorous nematodes increased in all treatments, in fallow and in planted pots and in the pots with high-copper, low-pH soil. The results of this experiment suggest that introduction of plant growth is one of the major causes of increased biological activity in acidic contaminated soils. Planting such soils with metal-tolerant plant species can reestablish the necessary food base to support soil organism growth, and this can lead to numerous positive effects, reversing the loss of soil functions due to the high copper levels under acidic conditions.

  9. In ovo administration of copper nanoparticles and copper sulfate positively influences chicken performance

    DEFF Research Database (Denmark)

    Mroczek-Sosnowska, Natalia; Łukasiewicz, Monika; Wnuk, Agnieszka

    2016-01-01

    BACKGROUND: Copper (Cu) is a key trace mineral involved in a variety of physiological processes, and is commonly used in poultry production. However, regardless of the inclusion level the majority of Cu is excreted with poultry faeces. We hypothesise that in ovo administration will allow for better...... utilisation of Cu during embryo development than when supplied post-natally with feed to growing chickens. Thus, the objective of this study was to evaluate effects of in ovo administration of NanoCu and copper sulfate (CuSO4 ) on broiler chicken performance. RESULTS: The study showed the positive influences...... of Cu nanoparticles and CuSO4 on broiler chickens performance. Body weight, at the end of the rearing period (day 42) was significantly higher in NanoCu (2206 g) and CuSO4 (2402 g) groups compared to the control group (2000 g). Both treatment groups had significantly lower feed conversion rate...

  10. Avoidance of copper and zinc by rainbow trout Oncorhynchus mykiss pre-exposed to copper.

    Science.gov (United States)

    Svecevičius, Gintaras

    2012-01-01

    Laboratory tests were conducted on 1-year-old rainbow trout Oncorhynchus mykiss in a counter-current flow, steep-gradient chamber to evaluate their ability to detect and avoid copper and zinc at concentrations of 0.1 mg Cu/L and 1 mg Zn/L, respectively, after 10-day pre-exposure to five copper sublethal concentrations ranging from 0.1 to 0.5 mg Cu/L and after 10-day re-acclimation period in clean water. Avoidance response intensity in affected fish significantly decreased with increase in pre-exposure Cu concentration. The strength of avoidance response to Cu and Zn test solutions in pre-exposed fish after re-acclimation gradually increased in a concentration-dependent order.

  11. Serum copper and ceruloplasmin levels and urinary copper excretion in thermal injury

    Energy Technology Data Exchange (ETDEWEB)

    Boosalis, M.G.; Solem, L.D.; Ahrenholz, D.H.; McCall, J.T.; McClain, C.J.

    1986-03-01

    Conflicting or incomplete reports exist regarding the copper (Cu) status of thermal injury patients. Therefore, the authors evaluated, longitudinally, serum levels of copper and ceruloplasmin (CP) and the 24-hr urinary excretion of Cu in 23 patients with 12-90% total body surface area (TBSA) 2nd and 3rd degree burns. Mean serum Cu level was below normal throughout hospitalization being lowest in patients with > 40% TBSA burn. Serum CP showed a similar pattern. To the authors knowledge, this is the only report of a decrease in serum Cu and CP levels post trauma. Mean urinary Cu excretion was elevated; the greater the TBSA burn, the greater the loss. The depression in serum Cu coincides with the depression in CP levels and is not a result of urinary losses. Clearly Cu status is altered in thermal injury. This injury may mimic a human Cu deficiency state requiring further investigation.

  12. Adsorption of aqueous copper on peanut hulls

    Science.gov (United States)

    Davis, Kanika Octavia

    A method was established for measuring the adsorption of Cu(II) from aqueous solution to unmodified and modified peanut hulls at constant temperature and pH. Modification of the hulls was performed by oxidation with alkaline hydrogen peroxide. During the modification process, the hydrogen peroxide solubilizes the lignin component, making the surface more porous which increases the availability of binding sites, while simultaneously oxidizing the cellulose. The oxidation of alcohol groups creates more binding sites by creating functional groups such as COO-, which increases chelation to metal ions. Fourier transform infrared spectroscopy confirms delignification of the peanut hulls by the disappearance of carboxyl peaks of the modified hulls, which were originally produced from the lignin content. Although, oxidation is not fully confirmed, it is not ruled out because the expected carboxylate peak (1680 cm-1) maybe overshadowed by a broad peak due to OH bending of water adsorbed to the hulls. Hulls adsorbed copper from solutions in the concentration range of 50-1000 ppm of CuCl2. Concentrations of pre- and post-adsorption solutions were determined using inductively coupled plasma optical emission spectroscopy. The adsorption isotherms were fit to known two and three-parameter models, evaluated and the binding mechanism was inferred. Maximum surface coverage was 3.5 +/- 0.6 mg Cu2+ /g hull for unmodified hulls and 11 +/- 1 mg Cu2+/g hull for modified hulls. The adsorption for the hulls is best described by the Langmuir model, suggesting monolayer, homogeneous adsorption. With a free energy of adsorption of 10.5 +/- 0.9 kJ/mol for unmodified hulls and 14.5 +/-0.4 kJ/mol for modified hulls, the process is categorized as chemisorption for both types of hulls. The adsorption for both hulls is also described by the Redlich-Peterson model, giving beta nearer to 1 than 0, which further suggests homogeneous adsorption described by the Langmuir model. After rinsing the hulls

  13. An Investigation of Low Biofouling Copper-charged Membranes

    Science.gov (United States)

    Asapu, Sunitha

    Water is essential for the survival of life on Earth, but pollutants in water can cause dangerous diseases and fatalities. The need for purified water has been increasing with increasing world population; however, natural sources of water such as rivers, lakes and streams, are progressively falling shorter and shorter of meeting water needs. The provision of clean, drinkable water to people is a key factor for the development of novel and alternative water purification technologies, such as membrane separations. Nanofiltration (NF) is a membrane separations technology that purifies water from lower quality sources, such as brackish water, seawater and wastewater. During the filtration of such sources, materials that are rejected by the membrane may accumulate on the surface of the membrane to foul it. Such materials include organic and inorganic matter, colloids, salts and microorganisms. The former four can often be controlled via pretreatment; however, the accumulation of microorganisms is more problematic to membranes. Biofouling is the accumulation and growth of microorganisms on the surface of membranes and on feed spacers. After attachment, microorganisms excrete extracellular polymeric substances (EPS), which form a matrix around the organism's outer surface as biofilm. These biofilms are detrimental and result in irreversible membrane fouling. Copper and silver ions inactivate the bacterial cells and prevent the DNA replication in microbial cells. Previous studies using copper-charged feed spacers have shown the ability of copper to control biofouling without a significant amount of copper leaching from copper-charged polypropylene (PP) feed spacers during crossflow filtration. Also, filtration using unmodified speed facers experienced almost 70% flux decline, while filtration using copper-charged feed spacers displayed only 25% flux decline. These intriguing results led to the hypothesis that the polymer chemistry could be extrapolated to produce membranes

  14. Micronized copper wood preservatives: An efficiency and potential health risk assessment for copper-based nanoparticles

    OpenAIRE

    Chiara Civardi Francis W.M.R. Schwarze Peter Wick

    2015-01-01

    Copper (Cu) is an essential biocide for wood protection but fails to protect wood against Cu tolerant wood destroying fungi. Recently Cu particles (size range: 1 nme25 mm) were introduced to the wood preservation market. The new generation of preservatives with Cu based nanoparticles (Cu based NPs) is reputedly more efficient against wood destroying fungi than conventional formulations. Therefore it has the potential to become one of the largest end uses for wood products worldwide. However d...

  15. Study of international published experiences in joining copper and copper-alloys

    International Nuclear Information System (INIS)

    Dahlgren, Aa.

    1997-04-01

    This study has revealed a number of joining processes to be used when manufacturing copper-canisters for the final storage of high level nuclear waste. However, the decision on which material and which joining process to be used has to be based on the design criterions. The welding procedure has to be qualified, i.e. it shall be demonstrated whether the procedure is capable of fulfilling specified requirements. 32 refs

  16. Electrochemical and morphological characterisation of polyphenazine films on copper

    Energy Technology Data Exchange (ETDEWEB)

    Gouveia-Caridade, Carla; Romeiro, Andreia; Brett, Christopher M.A., E-mail: cbrett@ci.uc.pt

    2013-11-15

    The morphology of films of the phenazine polymers poly(neutral red) (PNR), poly(brilliant cresyl blue) (PBCB), poly(Nile blue A) (PNB) and poly(safranine T) (PST), formed by potential cycling electropolymerisation on copper electrodes, in order to reduce the corrosion rate of copper, has been examined by scanning electron microscopy (SEM). The copper surface was initially partially passivated in sodium oxalate, hydrogen carbonate or salicylate solution, in order to inhibit copper dissolution at potentials where phenazine monomer oxidation occurs, and to induce better polymer film adhesion. SEM images were also taken of partially passivated copper in order to throw light on the different morphology and anti-corrosive behaviour of the polyphenazine films. Analysis of the morphology of the polymer-coated copper with best anti-corrosive behaviour after 72 h immersion in 0.1 M KCl, Cu/hydrogen carbonate/PNB, showed that the surface is completely covered by closely packed crystals. By contrast, images of PST films on copper partially passivated in oxalate solution, that had the least protective behaviour, showed large amounts of insoluble corrosion products after only 4 h immersion in 0.1 M KCl.

  17. Behaviors and mechanisms of copper adsorption on hydrolyzed polyacrylonitrile fibers.

    Science.gov (United States)

    Deng, Shubo; Bai, Renbi; Chen, J P

    2003-04-15

    Polyacrylonitrile fiber (PANF) was hydrolyzed in a solution of sodium hydroxide and the hydrolyzed polyacrylonitrile fiber (HPANF) was used as an adsorbent to remove copper ions from aqueous solution. Scanning electron microscopy (SEM) showed that the hydrolysis process made the surface of HPANF rougher than that of PANF. Fourier transform infrared (FTIR) spectroscopy revealed that the HPANF contained conjugated imine (-Cz=Nz-) sequences. Batch adsorption results indicated that the HPANF was very effective in adsorbing copper, and the adsorption equilibrium could be reached within 10-20 min. Atomic force microscopy (AFM) showed that some aggregates formed on the surface of the HPANF after copper ion adsorption and the average surface roughness (R(a)) value of the HPANF changed from 0.363 to 3.763 nm due to copper adsorption. FTIR analysis indicated that copper adsorption caused a decrease of the light adsorption intensity of the imine (-Cz=Nz-) groups at 1573 and 1406 cm(-1) wavenumbers, and X-ray photoelectron spectroscopy (XPS) showed that the binding energy (BE) of some of the nitrogen atoms in the HPANF increased to a greater value due to copper adsorption. The FTIR and XPS results suggest that the adsorption of copper ions to the HPANF is attributed to the imine groups on the surface of the HPANF.

  18. Effects of auxin and copper on growth of saffron

    Directory of Open Access Journals (Sweden)

    Mozafar Sharifi

    2014-03-01

    Full Text Available Saffron is known as one of the most common spices and medicinal plant in the world. Little information is available on the effects of copper and growth regulators on morphological characteristics of saffron. The aim of this study was to evaluate the influence of different concentrations of copper and auxin on morphological properties of root and leaf of saffron. This study was arranged as a factorial experiment in greenhouse condition and in hydroponic system. Copper was used in copper sulfate (CuSO4 form (0, 0.02, 0.1 and 0.2 mg/L and auxin in naphthalene acetic acid (NAA form (0, 1 and 2 g/L. Results showed that interaction of Naphthalene acetic acid 1 g/L and copper sulfate 0.1 mg/L increased root number, as well as root and leaf dry weight. Furthermore, naphthalene acetic acid 1 and 2 g/L in most treatments reduced the number of buds. Copper concentration of corm was increased in 0.2 mg/L copper sulfate.

  19. Guidelines for copper in sediments with varying properties.

    Science.gov (United States)

    Simpson, Stuart L; Batley, Graeme E; Hamilton, Ian L; Spadaro, David A

    2011-11-01

    A major weakness of sediment quality guidelines (SQGs) is their poor ability to predict how toxicity thresholds change for different sediment types. Using species sensitivity distributions (SSDs) of copper effects data, new guidelines were derived for copper in non-sulfidic marine sediments in which organic carbon (OC) and particle size strongly influence copper bioavailability. The derived SQGs varied in a predictable manner with changes in sediment particle size and organic carbon (OC), and were shown to offer a significant improvement on the existing 'single value' SQG. Adequate protection for all benthic organisms is expected to be achieved for a OC-normalised copper concentration of 3.5 mg Cu g(-1) OC in the high degree of conservatism owing to the use of copper-spiked sediments and laboratory-based bioassays that were expected to result in greater metal exposure of organisms to bioavailable copper than would be expected for field-contaminated sediments with similar total copper concentrations. SQGs that vary with sediment properties were prepared in an easily referenced tabular format. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  20. Synthesis of copper nanocolloids using a continuous flow based microreactor

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Lei, E-mail: xulei_kmust@aliyun.com [State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093 (China); Mechanical Engineering, University of Washington, Seattle 98195 (United States); Peng, Jinhui [State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093 (China); Srinivasakannan, C. [Chemical Engineering Program, The petroleum Institute, Abu Dhabi, P.O. Box 253 (United Arab Emirates); Chen, Guo [State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093 (China); Shen, Amy Q., E-mail: amy.shen@oist.jp [Mechanical Engineering, University of Washington, Seattle 98195 (United States); Micro/Bio/Nanofluidics Unit, Okinawa Institute of Technology Graduate University, Okinawa (Japan)

    2015-11-15

    Highlights: • The copper nanocolloidal were synthesized in a T-shaped microreactor at room temperature. • The morphology of copper nanocolloidal are spherical, and with good size distribution. • The mean particle diameter increased with decreases the NaBH{sub 4} molar concentration. • With increasing particle size, the more obvious localized surface plasmon resonance absorption. - Abstract: The copper (Cu) nanocolloids were prepared by sodium borohydride (NaBH{sub 4}) reduction of metal salt solutions in a T-shaped microreactor at room temperature. The influence of NaBH{sub 4} molar concentrations on copper particle's diameter, morphology, size distribution, and elemental compositions has been investigated by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The ultraviolet–visible spectroscopy (UV–vis) was used to verify the chemical compounds of nanocolloids and estimate the average size of copper nanocolloids. The synthesized copper nanocolloids were uniform in size and non-oxidized. A decrease in the mean diameter of copper nanocolloids was observed with increasing NaBH{sub 4} molar concentrations. The maximum mean diameter (4.25 nm) occurred at the CuSO{sub 4}/NaBH{sub 4} molar concentration ratio of 1:2.

  1. Photochemical Copper Coating on 3D Printed Thermoplastics

    Science.gov (United States)

    Yung, Winco K. C.; Sun, Bo; Huang, Junfeng; Jin, Yingdi; Meng, Zhengong; Choy, Hang Shan; Cai, Zhixiang; Li, Guijun; Ho, Cheuk Lam; Yang, Jinlong; Wong, Wai Yeung

    2016-08-01

    3D printing using thermoplastics has become very popular in recent years, however, it is challenging to provide a metal coating on 3D objects without using specialized and expensive tools. Herein, a novel acrylic paint containing malachite for coating on 3D printed objects is introduced, which can be transformed to copper via one-step laser treatment. The malachite containing pigment can be used as a commercial acrylic paint, which can be brushed onto 3D printed objects. The material properties and photochemical transformation processes have been comprehensively studied. The underlying physics of the photochemical synthesis of copper was characterized using density functional theory calculations. After laser treatment, the surface coating of the 3D printed objects was transformed to copper, which was experimentally characterized by XRD. 3D printed prototypes, including model of the Statue of Liberty covered with a copper surface coating and a robotic hand with copper interconnections, are demonstrated using this painting method. This composite material can provide a novel solution for coating metals on 3D printed objects. The photochemical reduction analysis indicates that the copper rust in malachite form can be remotely and photo-chemically reduced to pure copper with sufficient photon energy.

  2. Thermal conductivity of the pine-biocarbon-preform/copper composite

    Science.gov (United States)

    Parfen'eva, L. S.; Orlova, T. S.; Smirnov, B. I.; Smirnov, I. A.; Misiorek, H.; Jezowski, A.; Faber, K. T.

    2010-07-01

    The thermal conductivity of composites of a new type prepared by infiltration under vacuum of melted copper into empty sap channels (aligned with the sample length) of high-porosity biocarbon preforms of white pine tree wood has been studied in the temperature range 5-300 K. The biocarbon preforms have been prepared by pyrolysis of tree wood in an argon flow at two carbonization temperatures of 1000 and 2400°C. From the experimental values of the composite thermal conductivities, the fraction due to the thermal conductivity of the embedded copper is isolated and found to be substantially lower than that of the original copper used in preparation of the composites. The decrease in the thermal conductivity of copper in the composite is assigned to defects in its structure, namely, breaks in the copper filling the sap channels, as well as the radial ones, also filled by copper. A possibility of decreasing the thermal conductivity of copper in a composite due to its doping by the impurities present in the carbon preform is discussed.

  3. Laboratory evaluation of borate:amine:copper derivatives In wood for fungal decay protection

    Science.gov (United States)

    George Chen

    2011-01-01

    This study aimed to evaluate borate:amine:copper derivatives in wood for fungal decay protection as well as the permanence of copper and boron in wood. Each of four derivatives of borate:amine:copper prevented fungal decay in wood. Disodium tetraborate decahydrate (borax):amine:copper derivatives with 0.61-0.63% retention after water leaching prevented decay by...

  4. In vitro bioaccessibility of copper azole following simulated dermal transfer from pressure-treated wood

    Science.gov (United States)

    Micronized copper azole (MCA) and micronized copper quaternary are the latest wood preservatives to replace the liquid lkaline copper and chromated copper arsenate preservatives due to concerns over the toxicity or lack of effectiveness of the earlier formulations. Today, the use...

  5. Performance of copper-based wood preservatives in soil bed exposures

    Science.gov (United States)

    Stan T. Lebow; Thomas Nilsson; Jeffrey J. Morrell

    Copper-based biocides are widely used to protect wood from biological attack in a variety of environments. Chromated copper arsenate (CCA) is the dominant copper-based preservative for wood protection (J. T. MICKLEWRIGHT, 1989). First developed in India in the 1930s, CCA contains a very effective combination of materials. Copper provides protection against most...

  6. Assessment of the bioaccessibility of micronized copper wood in synthetic stomach fluid

    Science.gov (United States)

    The widespread use of copper in treated lumber may result in a potential for human exposure. Due to a lack of information concerning the release of copper from treated wood particles following oral ingestion, the in vitro bioaccessibility of copper from copper-treated wood dust i...

  7. The effect of an induced copper deficiency on the total plasma ...

    African Journals Online (AJOL)

    The effect of a copper deficiency on certain aspects of reproduction in ewes was investigated. An effective copper deficiency was induced by using the copper antagonists cadmium, calcium and sulphate. An average decline in the plasma copper concentration from 160 fLg/dlto 56 fLg/dlwas achieved. Further indications of ...

  8. Release of copper-amended particles from micronized copper-pressure-treated wood during mechanical abrasion.

    Science.gov (United States)

    Civardi, Chiara; Schlagenhauf, Lukas; Kaiser, Jean-Pierre; Hirsch, Cordula; Mucchino, Claudio; Wichser, Adrian; Wick, Peter; Schwarze, Francis W M R

    2016-11-28

    We investigated the particles released due to abrasion of wood surfaces pressure-treated with micronized copper azole (MCA) wood preservative and we gathered preliminary data on its in vitro cytotoxicity for lung cells. The data were compared with particles released after abrasion of untreated, water (0% MCA)-pressure-treated, chromated copper (CC)-pressure-treated wood, and varnished wood. Size, morphology, and composition of the released particles were analyzed. Our results indicate that the abrasion of MCA-pressure-treated wood does not cause an additional release of nanoparticles from the unreacted copper (Cu) carbonate nanoparticles from of the MCA formulation. However, a small amount of released Cu was detected in the nanosized fraction of wood dust, which could penetrate the deep lungs. The acute cytotoxicity studies were performed on a human lung epithelial cell line and human macrophages derived from a monocytic cell line. These cell types are likely to encounter the released wood particles after inhalation. Our findings indicate that under the experimental conditions chosen, MCA does not pose a specific additional nano-risk, i.e. there is no additional release of nanoparticles and no specific nano-toxicity for lung epithelial cells and macrophages.

  9. Effect of copper nanoparticles and copper sulphate on metabolic rate and development of broiler embryos

    DEFF Research Database (Denmark)

    Scott, Abdullah Talal Abudllah; Vadalasetty, Krishna Prasad; Sawosz, E.

    2016-01-01

    Copper (Cu) is regularly used as a growth promoter in poultry production. However, it has been demonstrated that the content of Cu inside eggs might not be sufficient to support the embryonic development. It is possible to supply the embryo with extra nutrients by in-ovo administration. Recently,...... not affected in the injected groups. In addition, blood parameters did not show any changes among the groups. This result demonstrates that in-ovo injection of Cu-NP affects the metabolic rate of embryos, which might explain their improved performance after hatching......., it has been shown that in-ovo administration of copper nanoparticles (Cu-NP) and copper sulphate (CuSO4) remarkably improved the body weights of growing chickens. Thus, the objective of the present experiment was to elucidate the potential effects of Cu-NP and CuSO4 on the metabolic rate (oxygen...... with Cu-NP (50 and 100 mg/kg). Gaseous exchange was measured in an open-air-circuit respiration unit, and EE was estimated from day 10 to day 19 of embryogenesis. Body weight at 24 h after hatching and the relative organ weights were used as a measure of hatching development. In-ovo injection of 50 mg...

  10. Antibacterial Effect of Copper on Microorganisms Isolated from Bovine Mastitis

    Science.gov (United States)

    Reyes-Jara, Angelica; Cordero, Ninoska; Aguirre, Juan; Troncoso, Miriam; Figueroa, Guillermo

    2016-01-01

    The antimicrobial properties of copper have been recognized for several years; applying these properties to the prevention of diseases such as bovine mastitis is a new area of research. The aim of the present study was to evaluate in vitro the antimicrobial activity of copper on bacteria isolated from subclinical and clinical mastitis milk samples from two regions in Chile. A total of 327 microorganisms were recovered between March and September 2013, with different prevalence by sample origin (25 and 75% from the central and southern regions of Chile, respectively). In the central region, Escherichia coli and coagulase negative Staphylococci (CNS) were the most frequently detected in clinical mastitis cases (33%), while in the southern region S. uberis, S. aureus, and CNS were detected with frequencies of 22, 21, and 18%, respectively. Antibiotic susceptibility studies revealed that 34% of isolates were resistant to one or more antibiotics and the resistance profile was different between bacterial species and origins of isolation of the bacteria. The minimum inhibitory concentration of copper (MIC-Cu) was evaluated in all the isolates; results revealed that a concentration as low as 250 ppm copper was able to inhibit the great majority of microorganisms analyzed (65% of isolates). The remaining isolates showed a MIC-Cu between 375 and 700 ppm copper, and no growth was observed at 1000 ppm. A linear relationship was found between the logarithm of viable bacteria number and time of contact with copper. With the application of the same concentration of copper (250 ppm), CNS showed the highest tolerance to copper, followed by S. uberis and S. aureus; the least resistant was E. coli. Based on these in vitro results, copper preparations could represent a good alternative to dipping solutions, aimed at preventing the presence and multiplication of potentially pathogenic microorganisms involved in bovine mastitis disease. PMID:27199953

  11. Improved dust handling at Inco's Copper Cliff smelter

    International Nuclear Information System (INIS)

    Dutton, A.; Warner, A.E.M.; Humphris, M.J.

    1989-01-01

    The Cooper Cliff Smelter Complex comprises three major production departments - a Nickel Smelter for the processing of nickel concentrated to a low iron, nickel - copper sulphide (Bessemer) matte; a Matte Processing plant for the separation of matte sulphides and the production of market nickel oxides and refinery feeds and a Copper Smelter to process copper concentrates to blister copper. Annual production is currently -114,000 tonnes of copper as blister and -110,000 tonnes of nickel. The nickel concentrate (11-13% Ni, 2-3% Cu) is roasted in multi-hearth roasters, smelted in oxy-fuel fired reverberatory furnaces to a 30-35% CuNiCo matte and converted to Bessemer matte (75% CuNiCo) in Peirce-Smith converters. The Bessemer matte is slow cooled and crushed for subsequent separation by mineral dressing techniques in the Matte Processing plant into nickel (sulphide and metallic) concentrates and a copper (chalcocite) concentrate. Nickel sulphides are further processed in fluid bed reactors to oxide market product or refinery feedstock. The copper concentrate (29-30% Cu, 0.9% No.) is dried in fluid bed driers, smelted to a 40-50% copper matte in an Inco oxygen flash furnace and converted to blister copper in Peirce-Smith converters. The chalcocite concentrate from the matte separation stage is flash converted to a semi-blister (3-4% S, 4-5% Ni) and then finished to lighter conventionally. A schematic process flowsheet of the Smelter Complex is shown in this paper

  12. Authorized limits for Fernald copper ingots

    International Nuclear Information System (INIS)

    Frink, N.; Kamboj, S.; Hensley, J.; Chen, S.Y.

    1997-09-01

    This development document contains data and analysis to support the approval of authorized limits for the unrestricted release of 59 t of copper ingots containing residual radioactive material from the U.S. Department of Energy (DOE) Fernald Environmental Management Project (FEMP). The analysis presented in this document comply with the requirements of DOE Order 5400.5, open-quotes Radiation Protection of the Public and the Environment,close quotes as well as the requirements of the proposed promulgation of this order as 10 CFR Part 834. The document was developed following the step-by-step process described in the Draft Handbook for Controlling Release for Reuse or Recycle Property Containing Residual Radioactive Material

  13. Authorized limits for Fernald copper ingots

    Energy Technology Data Exchange (ETDEWEB)

    Frink, N.; Kamboj, S.; Hensley, J.; Chen, S. Y.

    1997-09-01

    This development document contains data and analysis to support the approval of authorized limits for the unrestricted release of 59 t of copper ingots containing residual radioactive material from the U.S. Department of Energy (DOE) Fernald Environmental Management Project (FEMP). The analysis presented in this document comply with the requirements of DOE Order 5400.5, {open_quotes}Radiation Protection of the Public and the Environment,{close_quotes} as well as the requirements of the proposed promulgation of this order as 10 CFR Part 834. The document was developed following the step-by-step process described in the Draft Handbook for Controlling Release for Reuse or Recycle Property Containing Residual Radioactive Material.

  14. Copper alloys disintegration using pulsating water jet

    Czech Academy of Sciences Publication Activity Database

    Lehocká, D.; Klich, Jiří; Foldyna, Josef; Hloch, Sergej; Królczyk, J. B.; Cárach, J.; Krolczyk, G.

    2016-01-01

    Roč. 82, March 2016 (2016), s. 375-383 ISSN 0263-2241 R&D Projects: GA MŠk(CZ) LO1406; GA MŠk ED2.1.00/03.0082 Institutional support: RVO:68145535 Keywords : pulsating water jet * generation of pulses * disintegration * surface morphology * copper alloys Subject RIV: JQ - Machines ; Tools Impact factor: 2.359, year: 2016 http://ac.els-cdn.com/S0263224116000154/1-s2.0-S0263224116000154-main.pdf?_tid=8f8d1de6-99e9-11e6-afbc-00000aacb362&acdnat=1477314089_59912e52847e91e2030d6a1afd09e7b2

  15. Tunneling spectra of graphene on copper unraveled

    DEFF Research Database (Denmark)

    Zhang, Xin; Stradi, Daniele; Liu, Lei

    2016-01-01

    mechanisms, etc. The interpretation of the spectra can be complicated, however. Specifically for graphene grown on copper, there have been conflicting reports of tunneling spectra. A clear understanding of the mechanisms behind the variability is desired. In this work, we have revealed that the root cause...... of the variability in tunneling spectra is the variation in graphene-substrate coupling under various experimental conditions, providing a salutary perspective on the important role of 2D material-substrate interactions. The conclusions are drawn from measured data and theoretical calculations for monolayer, AB......-stacked bilayer, and twisted bilayer graphene coexisting on the same substrates in areas with and without intercalated oxygen, demonstrating a high degree of consistency. The Van Hove singularities of the twisted graphene unambiguously indicate the Dirac energy between them, lending strong evidence to our...

  16. Understanding the superconductivity in copper oxides

    CERN Document Server

    2019-01-01

    The aim of this book is to clarify the situation by adopting a very different approach from the above electronic/magnetic models, where explicitly local dynamical distortions are considered. These are distinctly different from conventional phonons which are a property of the infinite translational invariant symmetric lattice. The local dynamical distortions are shown to account for bulk properties and provide consistent and quantitative agreement with experimental data together with explicit predictions. Selected published experimental and theoretical papers are presented which support the above arguments, but have been ignored on purpose by the originators of the RVB/t-J bubble. To summarize the scope of this book, comprising nine chapters, it is shown, that the phenomenon of HTS in copper oxides is much better understood than publically claimed by RVB/t-J followers. Using the words of B. Laughlin, the presence of the antiferromagnetism in HTS masks the underlying physics where vibronic bipolarons with spin...

  17. Copper infiltrated high speed steels based composites

    International Nuclear Information System (INIS)

    Madej, M.; Lezanski, J.

    2003-01-01

    High hardness, mechanical strength, heat resistance and wear resistance of M3/2 high speed steel (HSS) make it an attractive material. Since technological and economical considerations are equally important, infiltration of high-speed steel skeleton with liquid cooper has proved to be a suitable technique whereby fully dense material is produced at low cost. Attempts have been made to describe the influence of the production process parameters and alloying additives, such as tungsten carbide on the microstructure and mechanical properties of copper infiltrated HSS based composites. The compositions of powder mixtures are 100% M3/2, M3/2+10% Wc, M3/2=30% WC. The powders were uniaxially cold compacted in a cylindrical die at 800 MPa. The green compacts were sintered in vacuum at 1150 o C for 60 minutes. Thereby obtained porous skeletons were subsequently infiltrated with cooper, by gravity method, in vacuum furnace at 1150 o C for 15 minutes. (author)

  18. Landscape Planning of Funiushan Copper Mine Wasteland

    Directory of Open Access Journals (Sweden)

    GUO Pan

    2015-04-01

    Full Text Available Traditional governance of mine waste land is given priority to recovery engineering, and pays the limited attention to the vegetation selection and landscape design. Taking the Nanjing Funiu copper mine as an example, the engineering geological conditions, the hydrological and geological conditions, soil type, climatic conditions, plant resources, mining sites and the surrounding economic and population development were well understood through field investigation and review of literature, and the 127 soil samples were collected and analyzed for soil heavy metal pollution of the region. The landscape planning ideas and concrete plans were proposed in this paper in order to play an exemplary role in ecological management and landscape planning of mine waste land.

  19. 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.

  20. Copper-rich invar by mechanical alloying

    Science.gov (United States)

    O'Donnell, K.; Qi, Qinian; Ilyushin, A. S.; Coey, J. M. D.

    1993-05-01

    An fcc alloy of composition Fe 64Cu 26Cr 7Ni 3 with a0 = 0.362 nm and an average crystalline size of 5 nm was produced by high-energy ball milling iron and copper powder in a stainless-steel container. The average number of electrons per atom is 8.7. The Curie temperature of the alloy is 410 K and the room-temperature magnetization is 48 JT -1 kg -1. The Mössbauer spectrum at 15 K shows a broad distribution of hyperfine field with an average of 15.6 T, which indicates coexistence of high and low moment states for iron. The alloy decomposes exothermically at 775 K to yield a mixture of bcc and fcc phases, but 50% of the iron remains in the fcc form with a low moment.

  1. Fracture toughness for copper oxide superconductors

    Science.gov (United States)

    Goretta, Kenneth C.; Kullberg, Marc L.

    1993-01-01

    An oxide-based strengthening and toughening agent, such as tetragonal Zro.sub.2 particles, has been added to copper oxide superconductors, such as superconducting YBa.sub.2 Cu.sub.3 O.sub.x (123) to improve its fracture toughness (K.sub.IC). A sol-gel coating which is non-reactive with the superconductor, such as Y.sub.2 BaCuO.sub.5 (211) on the ZrO.sub.2 particles minimized the deleterious reactions between the superconductor and the toughening agent dispersed therethrough. Addition of 20 mole percent ZrO.sub.2 coated with 211 yielded a 123 composite with a K.sub.IC of 4.5 MPa(m).sup.0.5.

  2. The copper cabel is not dead

    Energy Technology Data Exchange (ETDEWEB)

    Knutsen, Jan Grove

    2010-07-01

    It has for a long time been used old and proprietary communication solutions from vessel to subsea solutions, and between subsea installations. This has changed the last few years since standard industrial products are good enough to be in subsea installations. The biggest change is that Ethernet is used in most applications, and all Ethernet communication is based on open standards(IEEE). Since this now is standard equipment it means cost reduction and easy available support and products. This paper will describe how today's products make it possible to use old copper cables with today's technology. With this new technology it is possible to build advanced networks where you can benefit from redundancy functions and monitoring of your network. (Author)

  3. Symmetry in copper and silver cryptates

    International Nuclear Information System (INIS)

    The cryptand ligands imBT (1,4,7,10,13,16,21, 24-0ctaa2a-bicyclo [8.8.8]hexacosa- 4,6,13,15,21,23-hexaene) and amBT (1,4,7,10,13,16,21,24-Octaaza- bicyclo[8.8.8]hexacosane) form interesting disilver(I) and trisilver(l) cryptates, as well as a dicopper(I) and a well studied average valence dicopper(1.5) cryptate. Detailed structural and spectroscopic studies of the silver cryptates show that complex equilibria exist in solution, and the trisilver form appears to be thermodynamically favoured, the additional stabilisation apparently being due to argentophilic interactions. An optically pure form of the dicopper(I) imBT cryptate was successfully obtained, and is undergoing X-ray diffraction studies aimed at determining whether a copper-copper interaction exists, by direct examination of the electron density. Synthetic studies aimed at introducing substitution to the imBT and amBT ligands were complicated by competing reactions. A strategy to modify cryptand cavity size by incorporating asymmetric tetraamine caps succeeded, yielding dicopper(I) and disilver(I) cryptates with properties intermediate between cryptates incorporating the related symmetric caps. Manganese(II) cryptates of imBT and amBT were investigated as potential MRI contrast agents, the iminocryptate showing surprisingly high relaxivity, despite the fact that no water molecules were located in the crystal structure. The observation of high mass peaks in the FAB mass spectra of imBT and amBT cryptates suggests the presence of 6+4 Schiffbase condensation products, as well as the more abundant 3+2 products. It has not proved possible to isolate these molecules as yet, however initial studies aimed at a rational synthesis of the 6+4 condensation products were made, as these ligands could be of great interest for modelling the recently reported Cu z site. (author)

  4. Pulsed-DC selfsputtering of copper

    International Nuclear Information System (INIS)

    Wiatrowski, A; Posadowski, W M; Radzimski, Z J

    2008-01-01

    At standard magnetron sputtering conditions (argon pressure ∼0.5 Pa) inert gas particles are often entrapped in the formed films. Inert gas contamination can be eliminated by using the self-sustained magnetron sputtering process because it is done in the absence of the inert gas atmosphere. The self-sustained sputtering (SSS) gives also a unique condition during the transport of sputtered particles to the substrate. It is especially useful for filling high aspect ratio submicron scale structures for microelectronics. So far it has been shown that the self-sputtering process can be sustained in the DC operation mode (DC-SSS) only. The main disadvantage of DC-SSS process is instability related to possible arc formation. Usage of pulsed sputtering, similarly to reactive pulsed magnetron sputtering, could eliminate this problem. In this paper results of pulsed-DC self-sustained magnetron sputtering (pulsed DC-SSS) of copper are presented for the first time. The planar magnetron equipped with a 50 mm in diameter and 6 mm thick copper target was powered by DC-power supply modulated by power switch. The maximum target power was about 11 kW (∼550W/cm 2 ). The magnetron operation was investigated as a function of pulsing frequency (20-100 kHz) and duty factor (50-90%). The discharge extinction pressure was determined for these conditions. The plasma emission spectra (400-410nm range) and deposition rates were observed for both DC and pulsed DC sustained self-sputtering processes. The presented results illustrate that stable pulsed DC-SSS process can be obtained at pulsing frequency in the range of 60-100 kHz and duty factor of 70-90%

  5. Zinc and copper content of foods used in vegetarian diets.

    Science.gov (United States)

    Freeland-Graves, J H; Ebangit, M L; Bodzy, P W

    1980-12-01

    The zinc and copper content of seventy-four foods was determined by atomic absorption spectrophotometry. Each of these foods was reported to have been consumed by practicing vegetarians. Legumes, seeds, nuts, whole grains, hard cheeses, and some nutritional supplements were found to be excellent sources of both zinc and copper. Vegetables, fruits, and their products were generally poor sources of trace minerals, with the exception of seed and bean sprouts. Milk and milk products, including rennetless cheeses, contain small quantities of these minerals. Although many of the foods consumed by vegetarians do contain adequate amounts of zinc and copper, their bioavailability may be limited.

  6. Patterned electrochemical deposition of copper using an electron beam

    Directory of Open Access Journals (Sweden)

    Mark den Heijer

    2014-02-01

    Full Text Available We describe a technique for patterning clusters of metal using electrochemical deposition. By operating an electrochemical cell in the transmission electron microscope, we deposit Cu on Au under potentiostatic conditions. For acidified copper sulphate electrolytes, nucleation occurs uniformly over the electrode. However, when chloride ions are added there is a range of applied potentials over which nucleation occurs only in areas irradiated by the electron beam. By scanning the beam we control nucleation to form patterns of deposited copper. We discuss the mechanism for this effect in terms of electron beam-induced reactions with copper chloride, and consider possible applications.

  7. Sodium diethyldithiocarbamate as accelerator of the rate of copper cementation

    Directory of Open Access Journals (Sweden)

    Abeer A. El-Saharty

    2015-12-01

    Full Text Available The effects of Cu2+ ion concentration and temperature on the cementation rate of copper from copper sulphate on zinc and the effect of additives of the organic compound “sodium diethyldithiocarbamate” (NaDDC were studied. It was noticed that the cementation increases significantly by increasing the concentrations of NaDDC. The rate of cementation increased by 58.58−100.31%. Our data showed that sodium diethyldithiocarbamate reacts with the Cu2+ solution giving a complex of copper diethyldithiocarbamate, which enhances the rate of cementation.

  8. Chemical stability of copper-canisters in deep repository

    International Nuclear Information System (INIS)

    Ahonen, L.

    1995-12-01

    The spent fuel from Finnish nuclear reactors is planned to be encapsulated in thick-walled copper-iron canisters and placed deep into the bedrock. The copper wall of the canister provides a long-time shield against corrosion, preventing the high-level nuclear fuel from contact with ground water. In the report, stability of metallic copper and its possible corrosion reactions in the conditions of deep bedrock are evaluated by means of thermo-dynamic calculations. (90 refs., 28 figs., 11 tabs.)

  9. [Biomineralization of copper in Candida fukuyamaensis RCL-3].

    Science.gov (United States)

    Irazusta, Verónica; Michel, Lucas; de Figueroa, Lucía I C

    2016-01-01

    Candida fukuyamaensis RCL-3 yeast has the ability to decrease copper concentration in a culture medium. High copper concentrations change the cell color from white/cream to brown. The effect of color change ceases with the addition of KCN or when cells are grown in a culture medium without sulfate ions. These results could be associated with CuS bioaccumulation in the cell surface. This report revealed that mineralization would be a mechanism used by this yeast for copper bioremediation. Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  10. Residues of copper and sulphur on fruits from organic orchards

    OpenAIRE

    Kelderer, Markus; Matteazzi, Aldo; Casera, Claudio

    2004-01-01

    Copper und sulphur compounds are listed in annex 2b of the EC regulation 2091/92 and are used in organic orchards to control scab, mildew and sooty blotch also during summer time. In Italy, copper compounds have a waiting period from 20 days between last treatment and harvest, for sulphur compounds it differs and can reach until 30 days for lime sulphur. The trials carried out showed that using the recommended low dosages for copper and lime sulphur it should not be a problem t...

  11. 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

  12. Recrystallization of deformed copper - kinetics and microstructural evolution

    DEFF Research Database (Denmark)

    Lin, Fengxiang

    The objective of this study is to investigate the recrystallization kinetics and microstructural evolution in copper deformed to high strains, including copper deformed by cold-rolling and copper deformed by dynamic plastic deformation (DPD). Various characterization techniques were used, including...... electron backscatter diffraction (EBSD), Vickers hardness test, 3D X-ray diffraction (3DXRD) and differential scanning calorimetry (DSC). For the cold-rolled samples, a series of initial parameters was investigated for their effects on the recrystallization kinetics and textures, including initial grain...

  13. Inhibition of copper dissolution in water solutions of triazoles

    Science.gov (United States)

    Kuznetsov, Yu. I.; Agafonkina, M. O.; Andreeva, N. P.

    2014-04-01

    The influence of the chemical structure of certain triazoles on the inhibition of copper dissolution in water solutions at pH 7.40 is studied by electrochemical and ellispometric means. It is established that adsorption of the studied triazoles on copper at potential E = 0.0 V relative to a normal hydrogen electrode is polymolecular, the first layer is described by the Frumkin equation with values of the free adsorption of energy values (-Δ G {a/0}) = 50.5-70.1 kJ/mol. In addition, possible orientations of triazole molecules with respect to a surface of oxidized copper are revealed.

  14. The effects of impurities on the properties of OFP copper specified for the copper iron canister

    International Nuclear Information System (INIS)

    Bowyer, W.H.

    1999-09-01

    A brief literature study has addressed the effects of impurities on OF copper to which 50 ppm of phosphorus has been added. This copper is the candidate material for the corrosion resistant coating to be applied to the container under development by SKB for the disposal of high level nuclear waste. The levels of impurities expected in this grade of copper and the final use have controlled the focus of the work. It is concluded that the impurities of greatest importance in the context of the proposed application are sulphur, phosphorus, bismuth and lead. The addition of 50 ppm of phosphorus should ensure very low oxygen content in the copper such that, As, Ni, Mn, Cr, Fe, Sn, Zn, Si, Al, Sb and Cd present as impurities all remain in solution in the copper at all temperatures of interest. In this state they will exert no material effect on the fitness for purpose of the material. Sulphur is expected to be present in amounts exceeding the solubility limit such that it will occur as grain boundary films or particles. Such segregation can cause embrittlement and it will be more serious as grain size increases. There is no evidence to support the assertion that the phosphorus addition modifies the segregation behaviour of sulphur. There is evidence that sulphur will combine with V, Zr, or Ti, even when they are present at extremely low levels, but there is no indication of the likely effects of these combinations on the segregation behaviour or embrittling effects. There is clear evidence that when creep failure occurs by intergranular cracking, sulphur causes the creep strain to fracture to be reduced to less than 1%. The amount of sulphur required for this is very low (i.e. less than the amount permitted in the specification) and dependant on grain size. The transition from transgranular to intergranular failure in creep is influenced by temperature, stress, grain size, and composition. The addition of phosphorus increases the temperature at which the transition occurs

  15. The effects of impurities on the properties of OFP copper specified for the copper iron canister

    Energy Technology Data Exchange (ETDEWEB)

    Bowyer, W.H. [Meadow End Farm, Farnham (United Kingdom)

    1999-09-01

    A brief literature study has addressed the effects of impurities on OF copper to which 50 ppm of phosphorus has been added. This copper is the candidate material for the corrosion resistant coating to be applied to the container under development by SKB for the disposal of high level nuclear waste. The levels of impurities expected in this grade of copper and the final use have controlled the focus of the work. It is concluded that the impurities of greatest importance in the context of the proposed application are sulphur, phosphorus, bismuth and lead. The addition of 50 ppm of phosphorus should ensure very low oxygen content in the copper such that, As, Ni, Mn, Cr, Fe, Sn, Zn, Si, Al, Sb and Cd present as impurities all remain in solution in the copper at all temperatures of interest. In this state they will exert no material effect on the fitness for purpose of the material. Sulphur is expected to be present in amounts exceeding the solubility limit such that it will occur as grain boundary films or particles. Such segregation can cause embrittlement and it will be more serious as grain size increases. There is no evidence to support the assertion that the phosphorus addition modifies the segregation behaviour of sulphur. There is evidence that sulphur will combine with V, Zr, or Ti, even when they are present at extremely low levels, but there is no indication of the likely effects of these combinations on the segregation behaviour or embrittling effects. There is clear evidence that when creep failure occurs by intergranular cracking, sulphur causes the creep strain to fracture to be reduced to less than 1%. The amount of sulphur required for this is very low (i.e. less than the amount permitted in the specification) and dependant on grain size. The transition from transgranular to intergranular failure in creep is influenced by temperature, stress, grain size, and composition. The addition of phosphorus increases the temperature at which the transition occurs

  16. Als1 and Als3 regulate the intracellular uptake of copper ions when Candida albicans biofilms are exposed to metallic copper surfaces.

    Science.gov (United States)

    Zheng, Sha; Chang, Wenqiang; Li, Chen; Lou, Hongxiang

    2016-05-01

    Copper surfaces possess efficient antimicrobial effect. Here, we reported that copper surfaces could inactivate Candida albicans biofilms within 40 min. The intracellular reactive oxygen species in C. albicans biofilms were immediately stimulated during the contact of copper surfaces, which might be an important factor for killing the mature biofilms. Copper release assay demonstrated that the copper ions automatically released from the surface of 1 mm thick copper coupons with over 99.9% purity are not the key determinant for the copper-mediated killing action. The susceptibility test to copper surfaces by using C. albicans mutant strains, which were involved in efflux pumps, adhesins, biofilms formation or osmotic stress response showed that als1/als1 and als3/als3 displayed higher resistance to the copper surface contact than other mutants did. The intracellular concentration of copper ions was lower in als1/als1 and als3/als3 than that in wild-type strain. Transcriptional analysis revealed that the expression of copper transporter-related gene, CRP1, was significantly increased in als1/als1, als3/als3, suggesting a potential role of ALS1 and ALS3 in absorbing ions by regulating the expression of CRP1 This study provides a potential application in treating pathogenic fungi by using copper surfaces and uncovers the roles of ALS1 and ALS3 in absorbing copper ions for C. albicans. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Mycobacterium tuberculosis and Copper: A Newly Appreciated Defense against an Old Foe?*

    Science.gov (United States)

    Darwin, K. Heran

    2015-01-01

    Several independent studies have recently converged upon the conclusion that the human bacterial pathogen Mycobacterium tuberculosis encounters copper during infections. At least three independently regulated pathways respond to excess copper and are required for the full virulence of M. tuberculosis in animals. In this review, I will discuss the functions of the best-characterized copper-responsive proteins in M. tuberculosis, the potential sources of copper during an infection, and remaining questions about the interface between copper and tuberculosis. PMID:26055711

  18. The effect of antimony presence in anodic copper on kinetics and mechanism of anodic dissolution and cathodic deposition of copper

    Directory of Open Access Journals (Sweden)

    Stanković Z.D.

    2008-01-01

    Full Text Available The influence of the presence of Sb atoms, as foreign metal atoms in anode copper, on kinetics, and, on the mechanism of anodic dissolution and cathodic deposition of copper in acidic sulfate solution has been investigated. The galvanostatic single-pulse method has been used. Results indicate that presence of Sb atoms in anode copper increase the exchange current density as determined from the Tafel analysis of the electrode reaction. It is attributed to the increase of the crystal lattice parameter determined from XRD analysis of the electrode material.

  19. Copper and selenium supplementation in the diet of Brangus steers on the nutritional characteristics of meat

    Directory of Open Access Journals (Sweden)

    Arlindo Saran Netto

    2013-01-01

    Full Text Available Twenty-eight Brangus cattle were used to determine the effect of copper and selenium supplementation on the carcass characteristics, fatty acid composition of the longissimus dorsi muscle and on the copper and selenium concentrations in the liver. The treatments were: no supplementation of copper or selenium; 2 mg Se/kg DM as sodium selenite; 40 mg Cu/kg DM as copper sulfate; and 2 mg Se/kg DM as sodium selenite and 40 mg Cu/kg DM as copper sulfate. The fat thickness, rib eye area and fatty acid composition of the longissimus dorsi muscle were not affected by treatments. There was no effect on carcass yield and cooling loss with the supplementation of copper, selenium or selenium × copper in the levels studied. For the ether extract concentration in the longissimus dorsi muscle, no differences were found according to the treatments with selenium, copper or selenium × copper. The treatments with selenium and selenium × copper showed higher selenium concentrations in the liver than the control and copper treatments. For the copper concentration in the liver, the copper and selenium × copper treatments showed higher values than the control and selenium treatments. Despite the little effect on the meat composition, the results of this experiment demonstrate no interaction between selenium and copper in the levels studied.

  20. Saddling up copper - new twists on a metallo-wheel.

    Science.gov (United States)

    Zarrabi, Niloofar; Hayward, John J; Clegg, William; Pilkington, Melanie

    2014-02-14

    A unique octanuclear copper(II) cluster with a saddle-shaped structural topology has been prepared from a large, flexible polydentate ligand comprising a 4,4'-bipyridine linker bearing four pendant pyrazolate heterocycles.