Layered vanadyl (IV) nitroprusside: Magnetic interaction through a network of hydrogen bonds

Energy Technology Data Exchange (ETDEWEB)

Gil, D.M. [Instituto de Química Física, Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, San Lorenzo 456, T4000CAN San Miguel de Tucumán (Argentina); Osiry, H. [Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Unidad Legaria, Instituto Politécnico Nacional, México (Mexico); Pomiro, F.; Varetti, E.L. [CEQUINOR (CONICET-UNLP), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 and 115, 1900, La Plata (Argentina); Carbonio, R.E. [INFIQC – CONICET, Departamento de Físico Química, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre esq, Medina Allende, Ciudad Universitaria, X5000HUA Córdoba (Argentina); Alejandro, R.R. [Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Unidad Legaria, Instituto Politécnico Nacional, México (Mexico); Ben Altabef, A. [INQUINOA-UNT-CONICET, Instituto de Química Física, Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, San Lorenzo 456, T4000CAN San Miguel de Tucumán (Argentina); and others

2016-07-15

The hydrogen bond and π-π stacking are two non-covalent interactions able to support cooperative magnetic ordering between paramagnetic centers. This contribution reports the crystal structure and related magnetic properties for VO[Fe(CN){sub 5}NO]·2H{sub 2}O, which has a layered structure. This solid crystallizes with an orthorhombic unit cell, in the Pna2{sub 1} space group, with cell parameters a=14.1804(2), b=10.4935(1), c=7.1722(8) Å and four molecules per unit cell (Z=4). Its crystal structure was solved and refined from powder X-ray diffraction data. Neighboring layers remain linked through a network of hydrogen bonds involving a water molecule coordinated to the axial position for the V atom and the unbridged axial NO and CN ligands. An uncoordinated water molecule is found forming a triple bridge between these last two ligands and the coordinated water molecule. The magnetic measurements, recorded down to 2 K, shows a ferromagnetic interaction between V atoms located at neighboring layers, with a Curie-Weiss constant of 3.14 K. Such ferromagnetic behavior was interpreted as resulting from a superexchange interaction through the network of strong OH····O{sub H2O}, OH····N{sub CN}, and OH····O{sub NO} hydrogen bonds that connects neighboring layers. The interaction within the layer must be of antiferromagnetic nature and it was detected close to 2 K. - Graphical abstract: Coordination environment for the metals in vanadyl (II) nitroprusside dihydrate. Display Omitted - Highlights: • Crystal structure of vanadyl nitroprusside dehydrate. • Network of hydrogen bonds. • Magnetic interactions through a network of hydrogen bonds. • Layered transition metal nitroprussides.

Evaluation of biocidal efficacy of copper alloy coatings in comparison with solid metal surfaces: generation of organic copper phosphate nanoflowers.

Science.gov (United States)

Gutierrez, H; Portman, T; Pershin, V; Ringuette, M

2013-03-01

To analyse the biocidal efficacy of thermal sprayed copper surfaces. Copper alloy sheet metals containing >60% copper have been shown to exhibit potent biocidal activity. Surface biocidal activity was assessed by epifluorescence microscopy. After 2-h exposure at 20 °C in phosphate-buffered saline (PBS), contact killing of Gram-negative Escherichia coli and Gram-positive Staphylococcus epidermidis by brass sheet metal and phosphor bronze was 3-4-times higher than that by stainless steel. SEM observations revealed that the surface membranes of both bacterial strains were slightly more irregular when exposed to brass sheet metal than stainless steel. However, when exposed to phosphor bronze coating, E. coli were 3-4 times larger with irregular membrane morphology. In addition, the majority of the cells were associated with spherical carbon-copper-phosphate crystalline nanostructures characteristic of nanoflowers. The membranes of many of the S. epidermidis exhibited blebbing, and a small subset was also associated with nanoflowers. Our data indicate that increasing the surface roughness of copper alloys had a pronounced impact on the membrane integrity of Gram-positive and, to a lesser degree, Gram-negative bacteria. In the presence of PBS, carbon-copper-phosphate-containing nanoflowers were formed, likely nucleated by components derived from killed bacteria. The intimate association of the bacteria with the nanoflowers and phosphor bronze coating likely contributed to their nonreversible adhesion. Thermal spraying of copper alloys provides a strategy for the rapid coating of three-dimensional organic and inorganic surfaces with biocidal copper alloys. Our study demonstrates that the macroscale surface roughness generated by the thermal spray process enhances the biocidal activity of copper alloys compared with the nanoscale surface roughness of copper sheet metals. Moreover, the coating surface topography provides conditions for the rapid formation of organic copper

Analysis of copper losses throughout weak acid effluent flows generated during off-gas treatment in the New Copper Smelter RTB Bor

Directory of Open Access Journals (Sweden)

Dragana Ivšić-Bajčeta

2013-09-01

Full Text Available The previous inadequate treatment of off-gas in RTB Bor in Serbia has resulted in serious pollution of the environment and the possibly high losses of copper through the effluent flows. The project of New Copper Smelter RTB Bor, besides the new flash smelting furnace (FSF and the reconstruction of Pierce-Smith converter (PSC, includes more effective effluent treatment. Paper presents an analysis of the new FSF and PSC off-gas treatment, determination of copper losses throughout generated wastewaters and discussion of its possible valorization. Assumptions about the solubility of metals phases present in the FSF and PSC off-gas, obtained by the treatment process simulation, were compared with the leaching results of flue dusts. Determined wastewaters characteristics indicate that the PSC flow is significantly richer in copper, mostly present in insoluble metallic/sulfide form, while the FSF flow has low concentration of copper in the form of completely soluble oxide/sulfate. The possible scenario for the copper valorization, considering arsenic and lead as limiting factors, is the separation of the FSF and PSC flows, return of the metallic/sulfide solid phase to the smelting process and recovery from the sulfate/oxide liquid phase.

Mercury (I) nitroprusside: A 2D structure supported on homometallic interactions

Energy Technology Data Exchange (ETDEWEB)

Osiry, H.; Cano, A. [Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Unidad Legaria, Instituto Politécnico Nacional, México (Mexico); Reguera, L. [Facultad de Química, Universidad de La Habana (Cuba); Lemus-Santana, A.A. [Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Unidad Legaria, Instituto Politécnico Nacional, México (Mexico); Reguera, E., E-mail: edilso.reguera@gmail.com [Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Unidad Legaria, Instituto Politécnico Nacional, México (Mexico)

2015-01-15

The pentacyanonitrosylferrate complex anion, [Fe(CN){sub 5}NO]{sup 2−}, forms an insoluble solid with Hg(I) ion, of formula unit Hg{sub 2}[Fe(CN){sub 5}NO]·2H{sub 2}O, whose crystal structure and related properties are unknown. This contribution reports the preparation of that compound by the precipitation method and its structural study from X-ray powder patterns complemented with spectroscopic information from IR, Raman, and UV–vis techniques. The crystal structure was solved ab initio and then refined using the Rietveld method. The solid crystallizes with a triclinic unit cell, in the P−1 space group, with cell parameters a=10.1202(12), b=10.1000(13), c=7.4704(11) Å; α=110.664(10), β=110.114(10), γ=104.724(8) °. Within the unit cell, two formula units are accommodated (Z=2). It adopts a layered structure related with the coordination of the equatorial CN groups at their N end to the Hg atoms while the axial CN ligand remains unlinked. Within the layers neighboring Hg{sub 2}[Fe(CN){sub 5}NO] building units remain linked through four relatively strong Hg–Hg interactions, with an interatomic distance of 2.549(3) Å. The charge donation from the equatorial CN groups through their 5σ orbitals results into an increase for the electron density on the Hg atoms, which strengths the Hg–Hg bond. In the Raman spectrum, that metal–metal bond is detected as a stretching vibration band at 167 cm{sup −1}. The available free volume between neighboring layers accommodates two water molecules, which are stabilized within the framework through hydrogen bonds with the N end of the unlinked axial CN group. The removal of these weakly bonded water molecules results in structural disorder for the material 3D framework. - Graphical abstract: Assembling of Hg{sub 2}[Fe(CN){sub 5}NO] units through Hg–Hg interactions. - Highlights: • Homometallic Hg–Hg interactions in metal nitroprusside. • 2D structure supported on metal–metal interactions. • Crystal

Voltammetric Study of the Copper Pentacyanonitrosylferrate Adsorbed on the Silica Modified with a Poly(propyleneimine Hexadecylamine Dendrimer for Determination of Nitrite

Directory of Open Access Journals (Sweden)

D. R. do Carmo

2012-01-01

Full Text Available Poly(propyleneimine hexadecylamine dendrimer (DAB-Am-16 was anchored on the surface of 3-chloropropylsilyl silica gel and subsequently interacted with copper nitroprusside. The composite was characterized by infrared (FTIR, energy dispersive X-ray (EDX, and cyclic voltammetry. The above techniques confirmed the successful anchoring of the dendrimer on the silica gel modified surface and its interaction with copper nitroprusside. The cyclic voltammogram of CuNPSD was found to exhibit two redox couples with (Eθ′1 = 0.30 V and (Eθ′2 = 0.78 V versus Ag/AgCl (KCl=1.0 mol L−1; =20 mV s−1 attributed to the redox processes Cu(I/Cu(II and Fe(II(CN5NO/Fe(III(CN5NO, respectively. The CuNPSD-modified graphite paste electrode was found to show a linear response of 5.0×10−4 to 9.0×10−3 mol L−1 for nitrite determination with a detection limit (DL of 3.8×10−4 mol L−1 and an amperometric sensitivity of 25.0 mA/mol L−1. The CuNPSD-modified graphite paste electrode was found to show a good electrochemical stability and an excellent response to the electrocatalytic oxidation of sodium nitrite.

Plant polyphenols mobilize nuclear copper in human peripheral lymphocytes leading to oxidatively generated DNA breakage: implications for an anticancer mechanism.

Science.gov (United States)

Shamim, Uzma; Hanif, Sarmad; Ullah, M F; Azmi, Asfar S; Bhat, Showket H; Hadi, S M

2008-08-01

It was earlier proposed that an important anti-cancer mechanism of plant polyphenols may involve mobilization of endogenous copper ions, possibly chromatin-bound copper and the consequent pro-oxidant action. This paper shows that plant polyphenols are able to mobilize nuclear copper in human lymphocytes, leading to degradation of cellular DNA. A cellular system of lymphocytes isolated from human peripheral blood and comet assay was used for this purpose. Incubation of lymphocytes with neocuproine (a cell membrane permeable copper chelator) inhibited DNA degradation in intact lymphocytes. Bathocuproine, which is unable to permeate through the cell membrane, did not cause such inhibition. This study has further shown that polyphenols are able to degrade DNA in cell nuclei and that such DNA degradation is inhibited by neocuproine as well as bathocuproine (both of which are able to permeate the nuclear pore complex), suggesting that nuclear copper is mobilized in this reaction. Pre-incubation of lymphocyte nuclei with polyphenols indicates that it is capable of traversing the nuclear membrane. This study has also shown that polyphenols generate oxidative stress in lymphocyte nuclei which is inhibited by scavengers of reactive oxygen species (ROS) and neocuproine. These results indicate that the generation of ROS occurs through mobilization of nuclear copper resulting in oxidatively generated DNA breakage.

Operating experience gained during the copper oxide plugging incident in Koeberg unit 1 generator stator

International Nuclear Information System (INIS)

Mellor, S.P.; Matthee, F.W.

2002-01-01

In June 1999 Koeberg's unit 1 started to experience adverse operating conditions which were later ascribed to blockages in the hollow conductors of the generator stator. These blockages were attributed to copper oxide plugs which developed progressively during the following year and culminated in reduced power operation. Many attempts were made to address the plugging by implementing various off-line and on-line cleaning processes. Subsequent to a successful on-line cleaning operation, the unit was returned to full power and the chemistry regime for the stator cooling water system was changed to allow for operation at an elevated pH. This paper discusses Koeberg's experience with copper oxide blockages, describes the initial indications of the problem and the impact on the operating parameters. The remainder of the paper focuses on the actions taken to address the deteriorating situation and the different cleaning methods implemented to remove the copper oxide deposits. The paper concludes with the current status of the unit 1 generator stator and the lessons learned during the resolution of this problem. (authors)

Operating experience gained during the copper oxide plugging incident in Koeberg unit 1 generator stator

Energy Technology Data Exchange (ETDEWEB)

Mellor, S.P.; Matthee, F.W. [ESKOM, Koeberg Nuclear Power Station (South Africa)

2002-07-01

In June 1999 Koeberg's unit 1 started to experience adverse operating conditions which were later ascribed to blockages in the hollow conductors of the generator stator. These blockages were attributed to copper oxide plugs which developed progressively during the following year and culminated in reduced power operation. Many attempts were made to address the plugging by implementing various off-line and on-line cleaning processes. Subsequent to a successful on-line cleaning operation, the unit was returned to full power and the chemistry regime for the stator cooling water system was changed to allow for operation at an elevated pH. This paper discusses Koeberg's experience with copper oxide blockages, describes the initial indications of the problem and the impact on the operating parameters. The remainder of the paper focuses on the actions taken to address the deteriorating situation and the different cleaning methods implemented to remove the copper oxide deposits. The paper concludes with the current status of the unit 1 generator stator and the lessons learned during the resolution of this problem. (authors)

Trifluoperazine-Induced Suicidal Erythrocyte Death and S-Nitrosylation Inhibition, Reversed by the Nitric Oxide Donor Sodium Nitroprusside

Directory of Open Access Journals (Sweden)

Mehrdad Ghashghaeinia

2017-08-01

Full Text Available Background and Purpose: The high potency antipsychotic drug trifluoperazine (10-[3-(4-methyl-1-piperazinyl-propyl]-2-(trifluoromethyl-(10H-phenothiazine dihydrochloride; TFP may either counteract or promote suicidal cell death or apoptosis. Similar to apoptosis, erythrocytes may enter eryptosis, characterized by phosphatidylserine exposure at the cell surface and cell shrinkage. Eryptosis can be stimulated by an increase in cytoplasmic Ca2+ concentration ([Ca2+]i and inhibited by nitric oxide (NO. We explored whether TFP treatment of erythrocytes induces phosphatidylserine exposure, cell shrinkage, and calcium influx, whether it impairs S-nitrosylation and whether these effects are inhibited by NO. Methods: Phosphatidylserine exposure at the cell surface was estimated from annexin-V-binding, cell volume from forward scatter, [Ca2+]i from Fluo3-fluorescence, and protein nitrosylation from fluorescence switch of the Bodipy-TMR/Sypro Ruby signal. Results: Exposure of human erythrocytes to TFP significantly enhanced the percentage of annexin-V-binding cells, raised [Ca2+]i, and decreased S-nitrosylation. The effect of TFP on annexin-V-binding was not affected by removal of extracellular Ca2+ alone, but was significantly inhibited by pre-treatment with sodium nitroprusside (SNP, an effect significantly augmented by additional removal of extracellular Ca2+. A 3 hours treatment with 0.1 µM Ca2+ ionophore ionomycin triggered annexin-V-binding and cell shrinkage, effects fully reversed by removal of extracellular Ca2+. Conclusions: TFP induces eryptosis and decreases protein S-nitrosylation, effects blunted by nitroprusside. The effect of nitroprusside is attenuated in the presence of extracellular Ca2+.

Nickel, copper and cobalt coalescence in copper cliff converter slag

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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.

Placental vessels from type-1 diabetics and the effect of sodium nitroprusside

DEFF Research Database (Denmark)

Kristensen, Daniel; Brøgger, Torbjørn; Bødtkjer, Donna Briggs

NO-donor sodium nitroprusside (SNP). Results: Our preliminary data show that SVAs obtained from pregnancies complicated by T1DM have an impaired dilatory response to a single dose of SNP. The difference in the dilatory response to SNP shows a borderline significance (p = 0.057) after 60 seconds...... response to NO compared to uncomplicated pregnancies. Methods: The study setting is an experimental case-control study. Fresh delivered placentas from vaginal birth or caesarean section were obtained from cases (T1DM pregnancies) and controls (uncomplicated pregnancies) and the SVA dissected free under...

Inhibition by sodium nitroprusside of the expression of inducible nitric oxide synthase in rat neutrophils.

OpenAIRE

Mariotto, S; Cuzzolin, L; Adami, A; Del Soldato, P; Suzuki, H; Benoni, G

1995-01-01

A well-known nitric oxide (NO)-releasing compound, sodium nitroprusside (SNP), decreases in a dose-dependent manner NO synthase (NOS) activity induced in rat neutrophils by treatment with lipopolysaccharide (LPS). This inhibitory action of SNP seems not to be due to its direct effect on the enzyme activity. The strong nitrosonium ion (NO+) character of SNP could be responsible for its inhibition of NOS induction in neutrophils.

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.

Antioxidant properties of aqueous extracts of unripe Musa paradisiaca on sodium nitroprusside induced lipid peroxidation in rat pancreas in vitro.

Science.gov (United States)

Shodehinde, Sidiqat Adamson; Oboh, Ganiyu

2013-06-01

To evaluate and compare antioxidant activities of the aqueous extracts of unripe plantain (Musa paradisiaca), assess their inhibitory action on sodium nitroprusside induced lipid peroxidation in rat pancreas in vitro and to characterize the main phenolic constituents of the plantain products using gas chromatography analysis. Aqueous extracts of plantain products (raw, elastic pastry, roasted and boiled) flour of 0.1 g/mL (each) were used to determine their total phenol, total flavonoid, 1,1 diphenyl-2 picrylhydrazyl (DPPH) and hydroxyl (OH) radical scavenging ability. The inhibitory effect of the extracts on sodium nitroprusside induced lipid peroxidation was also determined. The results revealed that all the aqueous extracts showed antioxidant activity. The boiled flour had highest DPPH and OH radical scavenging ability while raw flour had the highest Fe(2+) chelating ability, sodium nitroprusside inhibitory effect and vitamin C content. The antioxidant results showed that elastic pastry had the highest total phenol and total flavonoid content. Characterization of the unripe plantain products for polyphenol contents using gas chromatography showed varied quantity of apigenin, myricetin, luteolin, capsaicin, isorhaemnetin, caffeic acid, kampferol, quercetin, p-hydroxybenzoic acid, shogaol, glycitein and gingerol per product on the spectra. Considering the antioxidant activities and ability to inhibit lipid peroxidation of unripe plantain, this could justify their traditional use in the management/prevention of diseases related to stress.

Antioxidant properties of aqueous extracts of unripe Musa paradisiaca on sodium nitroprusside induced lipid peroxidation in rat pancreas in vitro

Science.gov (United States)

Shodehinde, Sidiqat Adamson; Oboh, Ganiyu

2013-01-01

Objective To evaluate and compare antioxidant activities of the aqueous extracts of unripe plantain (Musa paradisiaca), assess their inhibitory action on sodium nitroprusside induced lipid peroxidation in rat pancreas in vitro and to characterize the main phenolic constituents of the plantain products using gas chromatography analysis. Methods Aqueous extracts of plantain products (raw, elastic pastry, roasted and boiled) flour of 0.1 g/mL (each) were used to determine their total phenol, total flavonoid, 1,1 diphenyl-2 picrylhydrazyl (DPPH) and hydroxyl (OH) radical scavenging ability. The inhibitory effect of the extracts on sodium nitroprusside induced lipid peroxidation was also determined. Results The results revealed that all the aqueous extracts showed antioxidant activity. The boiled flour had highest DPPH and OH radical scavenging ability while raw flour had the highest Fe2+ chelating ability, sodium nitroprusside inhibitory effect and vitamin C content. The antioxidant results showed that elastic pastry had the highest total phenol and total flavonoid content. Characterization of the unripe plantain products for polyphenol contents using gas chromatography showed varied quantity of apigenin, myricetin, luteolin, capsaicin, isorhaemnetin, caffeic acid, kampferol, quercetin, p-hydroxybenzoic acid, shogaol, glycitein and gingerol per product on the spectra. Conclusions Considering the antioxidant activities and ability to inhibit lipid peroxidation of unripe plantain, this could justify their traditional use in the management/prevention of diseases related to stress. PMID:23730557

Inhibition by sodium nitroprusside of the expression of inducible nitric oxide synthase in rat neutrophils.

Science.gov (United States)

Mariotto, S; Cuzzolin, L; Adami, A; Del Soldato, P; Suzuki, H; Benoni, G

1995-01-01

A well-known nitric oxide (NO)-releasing compound, sodium nitroprusside (SNP), decreases in a dose-dependent manner NO synthase (NOS) activity induced in rat neutrophils by treatment with lipopolysaccharide (LPS). This inhibitory action of SNP seems not to be due to its direct effect on the enzyme activity. The strong nitrosonium ion (NO+) character of SNP could be responsible for its inhibition of NOS induction in neutrophils. PMID:7542530

The effect of sodium nitroprusside on cerebral hemodynamics and headache in healthy subjects

DEFF Research Database (Denmark)

Guo, Song; Ashina, Messoud; Olesen, Jes

2013-01-01

InvestigationSodium nitroprusside (SNP) is a powerful vasodilatory agent that, similarly to glyceryl trinitrate (GTN), releases nitric oxide (NO) but in contrast does not pass the blood-brain barrier. Nevertheless, it has already been used in animal models without any knowledge of its headache......-inducing potential. We hypothesized that SNP would induce headache and vasodilation of cephalic and radial but not cerebral arteries.MethodsFive healthy volunteers received intravenous infusions of SNP in a non-randomized dose-titration (1-5 µg/kg/min) study. We recorded headache intensity (verbal rating scale from...

Considering linear generator copper losses on model predictive control for a point absorber wave energy converter

International Nuclear Information System (INIS)

Montoya Andrade, Dan-El; Villa Jaén, Antonio de la; García Santana, Agustín

2014-01-01

Highlights: • We considered the linear generator copper losses in the proposed MPC strategy. • We maximized the power transferred to the generator side power converter. • The proposed MPC increases the useful average power injected into the grid. • The stress level of the PTO system can be reduced by the proposed MPC. - Abstract: The amount of energy that a wave energy converter can extract depends strongly on the control strategy applied to the power take-off system. It is well known that, ideally, the reactive control allows for maximum energy extraction from waves. However, the reactive control is intrinsically noncausal in practice and requires some kind of causal approach to be applied. Moreover, this strategy does not consider physical constraints and this could be a problem because the system could achieve unacceptable dynamic values. These, and other control techniques have focused on the wave energy extraction problem in order to maximize the energy absorbed by the power take-off device without considering the possible losses in intermediate devices. In this sense, a reactive control that considers the linear generator copper losses has been recently proposed to increase the useful power injected into the grid. Among the control techniques that have emerged recently, the model predictive control represents a promising strategy. This approach performs an optimization process on a time prediction horizon incorporating dynamic constraints associated with the physical features of the power take-off system. This paper proposes a model predictive control technique that considers the copper losses in the control optimization process of point absorbers with direct drive linear generators. This proposal makes the most of reactive control as it considers the copper losses, and it makes the most of the model predictive control, as it considers the system constraints. This means that the useful power transferred from the linear generator to the power

Copper Leaching from Copper-ethanolamine Treated Wood: Comparison of Field Test Studies and Laboratory Standard Procedures

OpenAIRE

Nejc Thaler; Miha Humar

2014-01-01

Copper-based compounds are some of the most important biocides for the protection of wood in heavy duty applications. In the past, copper was combined with chromium compounds to reduce copper leaching, but a recent generation of copper-based preservatives uses ethanolamine as a fixative. To elucidate the leaching of copper biocides from wood, Norway spruce (Picea abies) wood was treated with a commercial copper-ethanolamine solution with two different copper concentrations (cCu = 0.125% and 0...

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...

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

Science.gov (United States)

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

2016-01-01

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

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

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

Science.gov (United States)

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

2018-02-01

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

Fast discharging homopolar drum-type generator with gas bearing and flexible copper-fiber brushes

International Nuclear Information System (INIS)

Kibardin, A.S.; Komin, A.V.; Sojkin, V.F.; Frolkin, V.I.

1984-01-01

The description and results of testing schock-excited homopolar generator (SEHG) with a drum-type rotor, a gas bearing and flexible copper-fiber brushes are presented. SEHG has a magnetic core with two excitation coils with the designed field of 1.8-2 T in the gap. The drum-type titanium rotor has 80 kg, is 0.5 m in diameter, 0.25 m length and 0.05 m thick. SEHG power is 3.6 MJ, overall dimensions are 0.8x1 m. Single- and double-row bearings, representing an aluminium shell of 15 mm thick, established inside an external backward current lead and isolated from it, are used to control serviceability of a radial gas-static bearing, which is a support for an SEHG rotor. The bearing surface was covered with the colloidal graphite and had one or two rows by 24 openings for swelling. Brush units represent a bronze brush ring, containing 44 copper-fiber brushes. Tests results confirm serviceability of copper-fiber brushes with quite large dimensions and permit to count on producing the 2.4 MA electric discharge and 12 ms pulse rise time

Copper atomic-scale transistors.

Science.gov (United States)

Xie, Fangqing; Kavalenka, Maryna N; Röger, Moritz; Albrecht, Daniel; Hölscher, Hendrik; Leuthold, Jürgen; Schimmel, Thomas

2017-01-01

We investigated copper as a working material for metallic atomic-scale transistors and confirmed that copper atomic-scale transistors can be fabricated and operated electrochemically in a copper electrolyte (CuSO 4 + H 2 SO 4 ) in bi-distilled water under ambient conditions with three microelectrodes (source, drain and gate). The electrochemical switching-on potential of the atomic-scale transistor is below 350 mV, and the switching-off potential is between 0 and -170 mV. The switching-on current is above 1 μA, which is compatible with semiconductor transistor devices. Both sign and amplitude of the voltage applied across the source and drain electrodes ( U bias ) influence the switching rate of the transistor and the copper deposition on the electrodes, and correspondingly shift the electrochemical operation potential. The copper atomic-scale transistors can be switched using a function generator without a computer-controlled feedback switching mechanism. The copper atomic-scale transistors, with only one or two atoms at the narrowest constriction, were realized to switch between 0 and 1 G 0 ( G 0 = 2e 2 /h; with e being the electron charge, and h being Planck's constant) or 2 G 0 by the function generator. The switching rate can reach up to 10 Hz. The copper atomic-scale transistor demonstrates volatile/non-volatile dual functionalities. Such an optimal merging of the logic with memory may open a perspective for processor-in-memory and logic-in-memory architectures, using copper as an alternative working material besides silver for fully metallic atomic-scale transistors.

Effect of nitrofurans and NO generators on biofilm formation by Pseudomonas aeruginosa PAO1 and Burkholderia cenocepacia 370.

Science.gov (United States)

Zaitseva, Julia; Granik, Vladimir; Belik, Alexandr; Koksharova, Olga; Khmel, Inessa

2009-06-01

Antibacterial drugs in the nitrofuran series, such as nitrofurazone, furazidin, nitrofurantoin and nifuroxazide, as well as the nitric oxide generators sodium nitroprusside and isosorbide mononitrate in concentrations that do not suppress bacterial growth, were shown to increase the capacity of pathogenic bacteria Pseudomonas aeruginosa PAO1 and Burkholderia cenocepacia 370 to form biofilms. At 25-100microg/ml, nitrofurans 2-2.5-fold enhanced biofilm formation of P. aeruginosa PAO1, and NO donors 3-6-fold. For B. cenocepacia 370, the enhancement was 2-5-fold (nitrofurans) and 4.5-fold (sodium nitroprusside), respectively.

Chemical generation of volatile species of copper – Optimization, efficiency and investigation of volatile species nature

Czech Academy of Sciences Publication Activity Database

Šoukal, Jakub; Benada, Oldřich; Matoušek, Tomáš; Dědina, Jiří; Musil, Stanislav

2017-01-01

Roč. 977, JUL (2017), s. 10-19 ISSN 0003-2670 Institutional support: RVO:68081715 ; RVO:61388971 Keywords : generation of volatile species * copper * analytical atomic spectrometry Subject RIV: CB - Analytical Chemistry, Separation; EE - Microbiology, Virology (MBU-M) OBOR OECD: Analytical chemistry; Microbiology (MBU-M) Impact factor: 4.950, year: 2016

Impact of Neutral Point Current Control on Copper Loss Distribution of Five Phase PM Generators Used in Wind Power Plants

Directory of Open Access Journals (Sweden)

ARASHLOO, R. S.

2014-05-01

Full Text Available Efficiency improvement under faulty conditions is one of the main objectives of fault tolerant PM drives. This goal can be achieved by increasing the output power while reducing the losses. Stator copper loss not only directly affects the total efficiency, but also plays an important role in thermal stress generations of iron core. In this paper, the effect of having control on neutral point current is studied on the efficiency of five-phase permanent magnet machines. Open circuit fault is considered for both one and two phases, and the distribution of copper loss along the windings are evaluated in each case. It is shown that only by having access to neutral point, it is possible to generate less stator thermal stress and more mechanical power in five-phase permanent magnet generators. Wind power generation and their applications are kept in mind, and the results are verified via simulations and experimental tests on an outer-rotor type of five-phase PM machine.

Thermal conductivity of tungsten–copper composites

International Nuclear Information System (INIS)

Lee, Sang Hyun; Kwon, Su Yong; Ham, Hye Jeong

2012-01-01

Highlights: ► We present the temperature dependence of the thermophysical properties for tungsten–copper composite from room temperature to 400 °C. The powders of tungsten–copper were produced by the spray conversion method and the W–Cu alloys were fabricated by the metal injection molding. Thermal conductivity and thermal expansion of tungsten–copper composite was controllable by volume fraction copper. - Abstract: As the speed and degree of integration of semiconductor devices increases, more heat is generated, and the performance and lifetime of semiconductor devices depend on the dissipation of the generated heat. Tungsten–copper alloys have high electrical and thermal conductivities, low contact resistances, and low coefficients of thermal expansion, thus allowing them to be used as a shielding material for microwave packages, and heat sinks for high power integrated circuits (ICs). In this study, the thermal conductivity and thermal expansion of several types of tungsten–copper (W–Cu) composites are investigated, using compositions of 5–30 wt.% copper balanced with tungsten. The tungsten–copper powders were produced using the spray conversion method, and the W–Cu alloys were fabricated via the metal injection molding. The tungsten–copper composite particles were nanosized, and the thermal conductivity of the W–Cu alloys gradually decreases with temperature increases. The thermal conductivity of the W–30 wt.% Cu composite was 238 W/(m K) at room temperature.

Copper vapour laser with an efficient semiconductor pump generator having comparable pump pulse and output pulse durations

Energy Technology Data Exchange (ETDEWEB)

Yurkin, A A [P N Lebedev Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

2016-03-31

We report the results of experimental studies of a copper vapour laser with a semiconductor pump generator capable of forming virtually optimal pump pulses with a current rise steepness of about 40 A ns{sup -1} in a KULON LT-1.5CU active element. To maintain the operating temperature of the active element's channel, an additional heating pulsed oscillator is used. High efficiency of the pump generator is demonstrated. (lasers)

Effect of Copper and Iron Ions on the Sulphidizing Flotation of Copper Oxide in Copper Smelting Slag

Directory of Open Access Journals (Sweden)

Qing-qing Pan

2018-01-01

Full Text Available The treatment of smelting slag has attracted much attention nowadays. This study investigates the influence of Na2S, CuSO4, and FeCl3 on sulphidizing flotation of copper oxide. The results show that a proper Cu2+ concentration can increase the sulphidizing effect of copper oxide, while Fe3+ inhibits the sulphidizing effect. Further analysis shows that Cu2+ ions can reduce the surface potential, increase the S2− adsorption, then generate more polysulfide, and therefore promote the sulphidizing flotation. However, Fe3+ ions would increase the surface potential, reduce the S2− adsorption, generate more sulfur element, and therefore inhibit the sulphidizing flotation.

Preparation and characterization of a new hybrid material formed by reaction of cobalt (II) nitroprusside and octa(aminopropyl)silsesquioxane

International Nuclear Information System (INIS)

Magossi, Mariana de Souza; Carmo, Devaney Ribeiro do

2016-01-01

Full text: The term silsesquioxane etymologically refers to the nanostructured compounds that has structures that feature the empirical formula (RSiO 1,5 ) n , where R is a hydrogen atom or an organic group. Each silicon atom is connected on an average of 1.5 oxygen atoms and a group R (hydrocarbon, or an organic group) [1]. In this work, a new hybrid material (ACCoN) based on octa(aminopropyl)silsesquioxane (AC) and cobalt (II) nitroprusside have been prepared following a new synthesis route. Within this context, the objective of this work was to prepare and characterize this new material for electro analytical purposes. The ACCoN was characterized by several techniques such as: spectroscopy in the region of infrared (FTIR), Energy-Dispersive X-ray spectroscopy (EDS), Scanning Electron microscopy (SEM) and X-Ray Diffraction (XRD). The FTIR spectra showed absorption bands in 1106 cm -1 refer to the stretching vibration ν s (Si-O-Si) characteristics of the structure of silsesquioxane. An important vibration can be observed which is related to the stretching vibrations of the type νN-O which occurs near 1945 cm -1 , characteristic of the sodium nitroprusside, where in the ACCoN the νN-O is shifted for more high frequency (about 117 cm -1 ) relative to sodium nitroprusside. Additionally a drastic reduction of stretching vibrations intensity νC≡N was observed in the ACCoN. This fact is an indicative of the formation of the intervalence complex, where the CN- and metal centers are bound. Through SEM and EDS spectroscopies was observed clusters of cubic particles with an average size of 325 nm. The ACCoN presents the elements Si, O, N, Co and Fe in its structure. Therefore through the aforementioned spectroscopic analysis, we conclude that the preparation of ACCoN was successfully conducted. [1] Cordes, D. B.; Lickiss, P. D.; Rataboul, F. Chemical Reviews, vol. 110, p. 2081-2173 (2010). (author)

Preparation and characterization of a new hybrid material formed by reaction of cobalt (II) nitroprusside and octa(aminopropyl)silsesquioxane

Energy Technology Data Exchange (ETDEWEB)

Magossi, Mariana de Souza; Carmo, Devaney Ribeiro do, E-mail: marymagossi@gmail.com [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Ilha Solteira, SP (Brazil). Faculdade de Engenharia

2016-07-01

Full text: The term silsesquioxane etymologically refers to the nanostructured compounds that has structures that feature the empirical formula (RSiO{sub 1,5}){sub n}, where R is a hydrogen atom or an organic group. Each silicon atom is connected on an average of 1.5 oxygen atoms and a group R (hydrocarbon, or an organic group) [1]. In this work, a new hybrid material (ACCoN) based on octa(aminopropyl)silsesquioxane (AC) and cobalt (II) nitroprusside have been prepared following a new synthesis route. Within this context, the objective of this work was to prepare and characterize this new material for electro analytical purposes. The ACCoN was characterized by several techniques such as: spectroscopy in the region of infrared (FTIR), Energy-Dispersive X-ray spectroscopy (EDS), Scanning Electron microscopy (SEM) and X-Ray Diffraction (XRD). The FTIR spectra showed absorption bands in 1106 cm{sup -1} refer to the stretching vibration ν{sub s}(Si-O-Si) characteristics of the structure of silsesquioxane. An important vibration can be observed which is related to the stretching vibrations of the type νN-O which occurs near 1945 cm{sup -1}, characteristic of the sodium nitroprusside, where in the ACCoN the νN-O is shifted for more high frequency (about 117 cm{sup -1}) relative to sodium nitroprusside. Additionally a drastic reduction of stretching vibrations intensity νC≡N was observed in the ACCoN. This fact is an indicative of the formation of the intervalence complex, where the CN- and metal centers are bound. Through SEM and EDS spectroscopies was observed clusters of cubic particles with an average size of 325 nm. The ACCoN presents the elements Si, O, N, Co and Fe in its structure. Therefore through the aforementioned spectroscopic analysis, we conclude that the preparation of ACCoN was successfully conducted. [1] Cordes, D. B.; Lickiss, P. D.; Rataboul, F. Chemical Reviews, vol. 110, p. 2081-2173 (2010). (author)

Effect of Copper and Iron Ions on the Sulphidizing Flotation of Copper Oxide in Copper Smelting Slag

OpenAIRE

Qing-qing Pan; Hui-qing Peng

2018-01-01

The treatment of smelting slag has attracted much attention nowadays. This study investigates the influence of Na2S, CuSO4, and FeCl3 on sulphidizing flotation of copper oxide. The results show that a proper Cu2+ concentration can increase the sulphidizing effect of copper oxide, while Fe3+ inhibits the sulphidizing effect. Further analysis shows that Cu2+ ions can reduce the surface potential, increase the S2− adsorption, then generate more polysulfide, and therefore promote the sulphidizing...

[Therapy of low-output syndrome in patients following cardiopulmonary bypass with sodium nitroprusside and dopamine].

Science.gov (United States)

van Ackern, K; Franke, N; Peter, K

1978-01-01

In 12 patients with low output after open-heart surgery the therapeutic effect of vasodilatation with sodium nitroprusside (SNP) and dopamine was studied. All patients underwent aortocoronary bypass operations. After cardiopulmonary bypass, the cardiac index (CI) was 2.2 liters/min.m2. The pulmonary wedge pressure (PCWP) was about 20 mm Hg. Application of SNP lowered mean arterial pressure to 82 and PCWP to 13 mm Hg. Then PCWP was elevated to the control level by tranfusion of blood. This therapy increased CI by about 30% without positive inotropic intervention. Additional application of 5 micrograms dopamine/kg.min improved the CI to 3.8 liters/min.m2.

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.

Elaboration of Copper-Oxygen Mediated C–H Activation Chemistry in Consideration of Future Fuel and Feedstock Generation

Science.gov (United States)

Lee, Jung Yoon; Karlin, Kenneth D

2015-01-01

To contribute solutions for current energy concerns, improvements in the efficiency of C-H bond cleavage chemistry, e.g., selective oxidation of methane to methanol, could minimize losses in natural gas usage or produce feedstocks for fuels. Oxidative C-H activation is also a component of polysaccharide degradation, affording alternative biofuels from abundant biomass. Thus, an understanding of active-site chemistry in copper monooxygenases, those activating strong C-H bonds is briefly reviewed. Then, recent advances in the synthesis-generation and study of various copper-oxygen intermediates are highlighted. Of special interest are cupric-superoxide, Cu-hydroperoxo and Cu-oxy complexes. Such investigations can contribute to an enhanced future application of C-H oxidation or oxygenation processes using air, as concerning societal energy goals. PMID:25756327

Comparison and analysis of the efficiency of heat exchange of copper rod and copper wires current lead

International Nuclear Information System (INIS)

Fang, J.; Yu, T.; Li, Z.M.; Wei, B.; Qiu, M.; Zhang, H.J.

2013-01-01

Highlights: •An optimized design of HTS binary current leads is proposed. •Temperature distributions of two different current leads are calculated. •Experiments are done to certify the calculated temperature distributions. •The experiments proved that the copper wires increase security margins. -- Abstract: Current leads are the key components that connect the low-temperature and high temperature parts of the cryogenic system. Owing to the wide range of temperatures, current leads are the main sources of heat leakage. Since the HTS tapes have no resistance and the generated Joule heat is almost zero, HTS binary current leads can reduce heat leakage compared to the conventional leads. However, heat will still be generated and conducted to the cryogenic system through the copper parts of the HTS current leads. In order to reduce heat leakage by the copper parts of the HTS current leads, this paper presents an optimized design of the copper parts of HTS binary current leads. Inside the leads, the copper wires were applied as an alternative to the copper rod without changing the overall dimensions. Firstly, the differential function of heat transfer was derived. By solving the function, the optimum number of the copper wires and the temperature distribution of two different current leads were gotten. Then the experiment of the temperature distribution was done, and the experimental results were basically the same with the calculative results. The simulation and related experiments proved that the copper wire can increase security margins and reduce maximum temperatures under the same shunt current

Comparison and analysis of the efficiency of heat exchange of copper rod and copper wires current lead

Energy Technology Data Exchange (ETDEWEB)

Fang, J., E-mail: fangseer@sina.com [School of Electrical Engineering, Beijing Jiaotong University, Beijing (China); Yu, T. [School of Electrical Engineering, Beijing Jiaotong University, Beijing (China); Li, Z.M.; Wei, B.; Qiu, M.; Zhang, H.J. [China Electric Power Research Institute, Haidian District, Beijing (China)

2013-11-15

Highlights: •An optimized design of HTS binary current leads is proposed. •Temperature distributions of two different current leads are calculated. •Experiments are done to certify the calculated temperature distributions. •The experiments proved that the copper wires increase security margins. -- Abstract: Current leads are the key components that connect the low-temperature and high temperature parts of the cryogenic system. Owing to the wide range of temperatures, current leads are the main sources of heat leakage. Since the HTS tapes have no resistance and the generated Joule heat is almost zero, HTS binary current leads can reduce heat leakage compared to the conventional leads. However, heat will still be generated and conducted to the cryogenic system through the copper parts of the HTS current leads. In order to reduce heat leakage by the copper parts of the HTS current leads, this paper presents an optimized design of the copper parts of HTS binary current leads. Inside the leads, the copper wires were applied as an alternative to the copper rod without changing the overall dimensions. Firstly, the differential function of heat transfer was derived. By solving the function, the optimum number of the copper wires and the temperature distribution of two different current leads were gotten. Then the experiment of the temperature distribution was done, and the experimental results were basically the same with the calculative results. The simulation and related experiments proved that the copper wire can increase security margins and reduce maximum temperatures under the same shunt current.

Reactivity test between beryllium and copper

International Nuclear Information System (INIS)

Kawamura, H.; Kato, M.

1995-01-01

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

Synthesis and characterization of a new composite based on copper (II) and octa (aminopropil)silsesquioxane

International Nuclear Information System (INIS)

Magossi, M.S. de; Carmo, D.R. do

2014-01-01

In this work, a new compound based silsesquioxane and nitroprusside of copper was prepared starting from octa (aminopropyl)silsesquioxane following a new route of synthesis. The composite prepared as described ACCuN was preliminarily characterized by spectroscopic techniques, such as Infrared Spectroscopy in the Region of the Fourier transform (FTIR), Energy Dispersive X-ray (EDX), Scanning Electron Microscopy (SEM) and cyclic voltammetry (VC). The FTIR spectra showed absorption bands at 1106 cm"-"1 due to stretching Si-O-Si_(_ν_S_i_-_O_-_S_i_) characteristic of the structure of octa(aminopropylsilsesquioxane and absorption bands at 2063 cm"-"1 ascribed to the stretching NO_(_ν_N_-_O) and 2192 cm"-"1 attributed to the stretching C≡N_(_ν_≡N_). SEM and EDX observed cluster of cubic particles with an average size of approximately 241 nm, containing Si, O, N, Cu and Fe. Cyclic voltammogram of the material (ACCuN) showed a redox couple with average potential Eθ '= 0.73 V. (author)

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)

Pathogenic adaptations to host-derived antibacterial copper

Science.gov (United States)

Chaturvedi, Kaveri S.; Henderson, Jeffrey P.

2014-01-01

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

Copper Promoted Synthesis of Diaryl Ethers

OpenAIRE

Ghosh, Rajshekhar; Samuelson, Ashoka G

2004-01-01

An efficient protocol using copper based reagents for the coupling of aryl halides with phenols to generate diaryl ethers is described. Acopper( I) complex, [ Cu( CH3CN) (4)] ClO4, or the readily available copper( II) source, CuCO3 . Cu( OH) (2) . H2O ( in combination with potassium phosphate), can be used. Aryl halides and phenols with different steric and electronic demands have been used to assess the efficiency of the procedure. The latter source of copper gives better yields under all co...

Copper increases the ability of 6-hydroxydopamine to generate oxidative stress and the ability of ascorbate and glutathione to potentiate this effect: potential implications in Parkinson's disease.

Science.gov (United States)

Cruces-Sande, Antón; Méndez-Álvarez, Estefanía; Soto-Otero, Ramón

2017-06-01

Copper is an essential metal for the function of many proteins related to important cellular reactions and also involved in the synaptic transmission. Although there are several mechanisms involved in copper homeostasis, a dysregulation in this process can result in serious neurological consequences, including degeneration of dopaminergic neurons. 6-Hydroxydopamine is a dopaminergic neurotoxin mainly used in experimental models of Parkinson's disease, whose neurotoxicity has been related to its ability to generate free radicals. In this study, we examined the effects induced by copper on 6-OHDA autoxidation. Our data show that both Cu + and Cu 2+ caused an increase in • OH production by 6-OHDA autoxidation, which was accompanied by an increase in the rate of both p-quinone formation and H 2 O 2 accumulation. The presence of ascorbate greatly enhanced this process by establishing a redox cycle which regenerates 6-OHDA from its p-quinone. However, the presence of glutathione did not change significantly the copper-induced effects. We observed that copper is able to potentiate the ability of 6-OHDA to cause both lipid peroxidation and protein oxidation, with the latter including a reduction in free-thiol content and an increase in carbonyl content. Ascorbate also increases the lipid peroxidation induced by the action of copper and 6-OHDA. Glutathione protects against the copper-induced lipid peroxidation, but does not reduce its potential to oxidize free thiols. These results clearly demonstrate the potential of copper to increase the capacity of 6-OHDA to generate oxidative stress and the ability of ascorbate to enhance this potential, which may contribute to the destruction of dopaminergic neurons. © 2017 International Society for Neurochemistry.

Role of copper oxides in contact killing of bacteria.

Science.gov (United States)

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

2013-12-31

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

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

Aspergillus fumigatus Copper Export Machinery and Reactive Oxygen Intermediate Defense Counter Host Copper-Mediated Oxidative Antimicrobial Offense

Directory of Open Access Journals (Sweden)

Philipp Wiemann

2017-05-01

Full Text Available The Fenton-chemistry-generating properties of copper ions are considered a potent phagolysosome defense against pathogenic microbes, yet our understanding of underlying host/microbe dynamics remains unclear. We address this issue in invasive aspergillosis and demonstrate that host and fungal responses inextricably connect copper and reactive oxygen intermediate (ROI mechanisms. Loss of the copper-binding transcription factor AceA yields an Aspergillus fumigatus strain displaying increased sensitivity to copper and ROI in vitro, increased intracellular copper concentrations, decreased survival in challenge with murine alveolar macrophages (AMΦs, and reduced virulence in a non-neutropenic murine model. ΔaceA survival is remediated by dampening of host ROI (chemically or genetically or enhancement of copper-exporting activity (CrpA in A. fumigatus. Our study exposes a complex host/microbe multifactorial interplay that highlights the importance of host immune status and reveals key targetable A. fumigatus counter-defenses.

Copper Cable Recycling Technology. Innovative Technology Summary Report

International Nuclear Information System (INIS)

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

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.

Aerosolized PGE1, PGI2 and nitroprusside protect against vascular leakage in lung ischaemia-reperfusion.

Science.gov (United States)

Schütte, H; Löckinger, A; Seeger, W; Grimminger, F

2001-07-01

High permeability oedema is an important feature in lung injury secondary to ischaemia-reperfusion. This study investigated the influence of aerosolized prostaglandin E1 (PGE1), prostaglandin I2 (PCI2) and the nitric oxide (NO)-donor, sodium nitroprusside (SNP) on microvascular barrier function in pulmonary ischaemia-reperfusion. Buffer-perfused rabbit lungs were exposed to 180 or 210 min of warm ischaemia while maintaining anoxic ventilation and a positive intravascular pressure. Reperfusion provoked a transient, mostly precapillary elevation of vascular resistance, followed by a severe increase of the capillary filtration coefficient (Kfc) versus nonischaemic controls (3.17+/-0.34 versus 0.85+/-0.05 cm3 x s(-1) cmH2O(-1) x g(-1) x 10(-4) after 30 min of reperfusion), and progressive oedema formation. Short-term aerosolization of SNP, PGE1 or PGI2 at the beginning of ischaemia largely suppressed the Kfc increase (1.36+/-0.22, 1.32+/-0.23 and 1.32+/-0.22 cm3 x s(-1) x cmH2O(-1) x g(-1) x 10(-4), respectively) and oedema formation. In contrast, application prior to reperfusion was much less effective, with some reduction of Kfc increase by PGI2 and SNP and no effect of PGE, (1.79+/-0.31, 2.2+/-0.53 and 3.2+/-0.05 cm3 x s(-1) x cmH2O(-1) x g(-1) x 10(-4), respectively). Haemodynamics, including microvascular pressure, were only marginally affected by the chosen doses of aerosolized vasodilators. It is concluded that short-term aerosolization of prostaglandin E1, prostaglandin I2 and sodium nitroprusside at the onset of ischaemia is highly effective in maintaining endothelial barrier properties in pulmonary ischaemia-reperfusion. This effect is apparently attributable to nonvasodilatory mechanisms exerted by these agents. Alveolar deposition of prostaglandins and/or nitric oxide donors by the aerosol technique may offer pulmonary protection in ischaemia-reperfusion injury.

Estimating global copper demand until 2100 with regression and stock dynamics

NARCIS (Netherlands)

Schipper, Branco W.; Lin, Hsiu Chuan; Meloni, Marco A.; Wansleeben, Kjell; Heijungs, Reinout; van der Voet, Ester

2018-01-01

Future global copper demand is expected to keep rising due to copper's indispensable role in modern technologies. Unfortunately, increasing copper extraction and decreasing ore grades intensify energy use and generate higher environmental impact. A potential solution would be reaching a circular

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

Selenide isotope generator for the Galileo Mission: copper/water axially-grooved heat pipe topical report

International Nuclear Information System (INIS)

Strazza, N.P.

1979-01-01

This report presents a summary of the major accomplishments for the development, fabrication, and testing of axially-grooved copper/water heat pipes for Selenide Isotopic Generator (SIG) applications. The early development consisted of chemical, physical, and analytical studies to define an axially-grooved tube geometry that could be successfully fabricated and provide the desired long term (up to seven years) performance is presented. Heat pipe fabrication procedures, measured performance and accelerated life testing of heat pipes S/Ns AL-5 and LT-57 conducted at B and K Engineering are discussed. S/N AL-5 was the first axially-grooved copper/water heat pipe that was fabricated with the new internal coating process for cupric oxide (CuO) and the cleaning and water preparation methods developed by Battelle Columbus Laboratories. Heat pipe S/N LT-57 was fabricated along with sixty other axially-grooved heat pipes allocated for life testing at Teledyne Energy Systems. As of June 25, 1979, heat pipes S/Ns AL-5 and LT-57 have been accelerated life tested for 13,310 and 6,292 respectively, at a nominal operating temperature of 225 0 C without any signs of thermal performance degradation

Sodium nitroprusside induces autophagic cell death in glutathione-depleted osteoblasts.

Science.gov (United States)

Son, Min Jeong; Lee, Seong-Beom; Byun, Yu Jeong; Lee, Hwa Ok; Kim, Ho-Shik; Kwon, Oh-Joo; Jeong, Seong-Whan

2010-01-01

Previous studies reported that high levels of nitric oxide (NO) induce apoptotic cell death in osteoblasts. We examined molecular mechanisms of cytotoxic injury induced by sodium nitroprusside (SNP), a NO donor, in both glutathione (GSH)-depleted and control U2-OS osteoblasts. Cell viability was reduced by much lower effective concentrations of SNP in GSH-depleted cells compared to normal cells. The data suggest that the level of intracellular GSH is critical in SNP-induced cell death processes of osteoblasts. The level of oxidative stress due to SNP treatments doubled in GSH-depleted cells when measured with fluorochrome H2DCFDA. Pretreatment with the NO scavenger PTIO preserved the viability of cells treated with SNP. Viability of cells treated with SNP was recovered by pretreatment with Wortmannin, an autophagy inhibitor, but not by pretreatment with zVAD-fmk, a pan-specific caspase inhibitor. Large increases of LC3-II were shown by immunoblot analysis of the SNP-treated cells, and the increase was blocked by pretreatment with PTIO or Wortmannin; this implies that under GSH-depleted conditions SNP induces different molecular signaling that lead to autophagic cell death. The ultrastructural morphology of SNP-treated cells in transmission electron microscopy showed numerous autophagic vacuoles. These data suggest NO produces oxidative stress and cellular damage that culminate in autophagic cell death of GSH-depleted osteoblasts. Copyright 2010 Wiley Periodicals, Inc.

Copper, lead and zinc production

International Nuclear Information System (INIS)

Ayers, J.; Ternan, S.

2001-01-01

This chapter provides information on the by-products and residues generated during the production of copper, lead and zinc. The purpose of this chapter is to describe by-products and residues which are generated, how these may be avoided or minimised, and available options for the utilization and management of residues. (author)

Copper benchmark experiment at the Frascati Neutron Generator for nuclear data validation

Energy Technology Data Exchange (ETDEWEB)

Angelone, M., E-mail: maurizio.angelone@enea.it; Flammini, D.; Loreti, S.; Moro, F.; Pillon, M.; Villari, R.

2016-11-01

Highlights: • A benchmark experiment was performed using pure copper with 14 MeV neutrons. • The experiment was performed at the Frascati Neutron Generator (FNG). • Activation foils, thermoluminescent dosimeters and scintillators were used to measure reactions rates (RR), nuclear heating and neutron spectra. • The paper presents the RR measurements and the post analysis using MCNP5 and JEFF-3.1.1, JEFF-3.2 and FENDL-3.1 libraries. • C/Es are presented showing the need for deep revision of Cu cross sections. - Abstract: A neutronics benchmark experiment on a pure Copper block (dimensions 60 × 70 × 60 cm{sup 3}), aimed at testing and validating the recent nuclear data libraries for fusion applications, was performed at the 14-MeV Frascati Neutron Generator (FNG) as part of a F4E specific grant (F4E-FPA-395-01) assigned to the European Consortium on Nuclear Data and Experimental Techniques. The relevant neutronics quantities (e.g., reaction rates, neutron flux spectra, doses, etc.) were measured using different experimental techniques and the results were compared to the calculated quantities using fusion relevant nuclear data libraries. This paper focuses on the analyses carried-out by ENEA through the activation foils techniques. {sup 197}Au(n,γ){sup 198}Au, {sup 186}W(n,γ){sup 187}W, {sup 115}In(n,n′){sup 115}In, {sup 58}Ni(n,p){sup 58}Co, {sup 27}Al(n,α){sup 24}Na, {sup 93}Nb(n,2n){sup 92}Nb{sup m} activation reactions were used. The foils were placed at eight different positions along the Cu block and irradiated with 14 MeV neutrons. Activation measurements were performed by means of High Purity Germanium (HPGe) detector. Detailed simulation of the experiment was carried-out using MCNP5 Monte Carlo code and the European JEFF-3.1.1 and 3.2 nuclear cross-sections data files for neutron transport and IRDFF-v1.05 library for the reaction rates in activation foils. The calculated reaction rates (C) were compared to the experimental quantities (E) and

Ammonia leaching of copper smelter dust and precipitation as copper sulphide; Lixiviacion amoniacal de polvos de fundicion de cobre y precipitacion como sulfuro de cobre

Energy Technology Data Exchange (ETDEWEB)

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

2009-07-01

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.

In situ generation of nitrilium from nitrile ylide and the subsequent Mumm rearrangement: copper-catalyzed synthesis of unsymmetrical diacylglycine esters.

Science.gov (United States)

Chen, Jijun; Shao, Ying; Ma, Liang; Ma, Meihua; Wan, Xiaobing

2016-12-07

A novel in situ generation of nitrilium from a nitrile ylide and the subsequent Mumm rearrangement of carboxylic acid, nitrile, and diazo compounds gave various unsymmetrical diacylglycine esters in moderate to high yields. This copper-catalyzed cascade reaction enables one-pot generation of two C-N bonds, one C[double bond, length as m-dash]O bond, and one C-H bond, with nitrogen as the only byproduct. The reaction has a broad functional-group tolerance, is rapid, easily scales up to the 100 mmol scale, and is insensitive to air and moisture.

Co-culture with human synovium-derived mesenchymal stem cells inhibits inflammatory activity and increases cell proliferation of sodium nitroprusside-stimulated chondrocytes

International Nuclear Information System (INIS)

Ryu, Jae-Sung; Jung, Yeon-Hwa; Cho, Mi-Young; Yeo, Jee Eun; Choi, Yun-Jin; Kim, Yong Il; Koh, Yong-Gon

2014-01-01

Highlights: • Co-culture of hSDMSCs with SNP-stimulated chondrocytes improves anti-inflammation. • Co-culture system produces IGF-1. • Co-culture system suppresses inflammatory genes expression. • Co-culture system improves cell proliferation. • Exogenous IGF-1 inhibits inflammatory activity in SNP-stimulated chondrocytes. - Abstract: Rheumatoid arthritis (RA) and osteoarthritis (OA) are primarily chronic inflammatory diseases. Mesenchymal stem cells (MSCs) have the ability to differentiate into cells of the mesodermal lineage, and to regulate immunomodulatory activity. Specifically, MSCs have been shown to secrete insulin-like growth factor 1 (IGF-1). The purpose of the present study was to examine the inhibitory effects on inflammatory activity from a co-culture of human synovium-derived mesenchymal stem cells (hSDMSCs) and sodium nitroprusside (SNP)-stimulated chondrocytes. First, chondrocytes were treated with SNP to generate an in vitro model of RA or OA. Next, the co-culture of hSDMSCs with SNP-stimulated chondrocytes reduced inflammatory cytokine secretion, inhibited expression of inflammation activity-related genes, generated IGF-1 secretion, and increased the chondrocyte proliferation rate. To evaluate the effect of IGF-1 on inhibition of inflammation, chondrocytes pre-treated with IGF-1 were treated with SNP, and then the production of inflammatory cytokines was analyzed. Treatment with IGF-1 was shown to significantly reduce inflammatory cytokine secretion in SNP-stimulated chondrocytes. Our results suggest that hSDMSCs offer a new strategy to promote cell-based cartilage regeneration in RA or OA

Co-culture with human synovium-derived mesenchymal stem cells inhibits inflammatory activity and increases cell proliferation of sodium nitroprusside-stimulated chondrocytes

Energy Technology Data Exchange (ETDEWEB)

Ryu, Jae-Sung; Jung, Yeon-Hwa; Cho, Mi-Young; Yeo, Jee Eun; Choi, Yun-Jin; Kim, Yong Il; Koh, Yong-Gon, E-mail: yonseranglab@daum.net

2014-05-16

Highlights: • Co-culture of hSDMSCs with SNP-stimulated chondrocytes improves anti-inflammation. • Co-culture system produces IGF-1. • Co-culture system suppresses inflammatory genes expression. • Co-culture system improves cell proliferation. • Exogenous IGF-1 inhibits inflammatory activity in SNP-stimulated chondrocytes. - Abstract: Rheumatoid arthritis (RA) and osteoarthritis (OA) are primarily chronic inflammatory diseases. Mesenchymal stem cells (MSCs) have the ability to differentiate into cells of the mesodermal lineage, and to regulate immunomodulatory activity. Specifically, MSCs have been shown to secrete insulin-like growth factor 1 (IGF-1). The purpose of the present study was to examine the inhibitory effects on inflammatory activity from a co-culture of human synovium-derived mesenchymal stem cells (hSDMSCs) and sodium nitroprusside (SNP)-stimulated chondrocytes. First, chondrocytes were treated with SNP to generate an in vitro model of RA or OA. Next, the co-culture of hSDMSCs with SNP-stimulated chondrocytes reduced inflammatory cytokine secretion, inhibited expression of inflammation activity-related genes, generated IGF-1 secretion, and increased the chondrocyte proliferation rate. To evaluate the effect of IGF-1 on inhibition of inflammation, chondrocytes pre-treated with IGF-1 were treated with SNP, and then the production of inflammatory cytokines was analyzed. Treatment with IGF-1 was shown to significantly reduce inflammatory cytokine secretion in SNP-stimulated chondrocytes. Our results suggest that hSDMSCs offer a new strategy to promote cell-based cartilage regeneration in RA or OA.

Copper and Copper Proteins in Parkinson's Disease

Science.gov (United States)

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

2014-01-01

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

Copper regulation and homeostasis of Daphnia magna and Pseudokirchneriella subcapitata: influence of acclimation

International Nuclear Information System (INIS)

Bossuyt, Bart T.A.; Janssen, Colin R.

2005-01-01

This study aimed to evaluate (1) the capacity of the green alga Pseudokirchneriella subcapitata and the waterflea Daphnia magna to regulate copper when exposed to environmentally realistic copper concentrations and (2) the influence of multi-generation acclimation to these copper concentrations on copper bioaccumulation and homeostasis. Based on bioconcentration factors, active copper regulation was observed in algae up to 5 μg Cu L -1 and in daphnids up to 35 μg Cu L -1 . Constant body copper concentrations (13 ± 4 μg Cu g DW -1 ) were observed in algae exposed to 1 through 5 μg Cu L -1 and in daphnids exposed to 1 through 12 μg Cu L -1 . At higher exposure concentrations, there was an increase in internal body copper concentration, while no increase was observed in bioconcentration factors, suggesting the presence of a storage mechanism. At copper concentrations of 100 μg Cu L -1 (P. subcapitata) and 150 μg Cu L -1 (D. magna), the significant increases observed in body copper concentrations and in bioconcentration factors may be related to a failure of this regulation mechanism. For both organisms, internal body copper concentrations lower than 13 μg Cu g DW -1 may result in copper deficiency. For P. subcapitata acclimated to 0.5 and 100 μg Cu L -1 , body copper concentrations ranged (mean ± standard deviation) between 5 ± 2 μg Cu g DW -1 and 1300 ± 197 μg Cu g DW -1 , respectively. For D. magna, this value ranged between 9 ± 2 μg Cu g DW -1 and 175 ± 17 μg Cu g DW -1 for daphnids acclimated to 0.5 and 150 μg Cu L -1 . Multi-generation acclimation to copper concentrations ≥12 μg Cu L -1 resulted in a decrease (up to 40%) in body copper concentrations for both organisms compared to the body copper concentration of the first generation. It can be concluded that there is an indication that P. subcapitata and D. magna can regulate their whole body copper concentration to maintain copper homeostasis within their optimal copper range and

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

MHD Generating system

Science.gov (United States)

Petrick, Michael; Pierson, Edward S.; Schreiner, Felix

1980-01-01

According to the present invention, coal combustion gas is the primary working fluid and copper or a copper alloy is the electrodynamic fluid in the MHD generator, thereby eliminating the heat exchangers between the combustor and the liquid-metal MHD working fluids, allowing the use of a conventional coalfired steam bottoming plant, and making the plant simpler, more efficient and cheaper. In operation, the gas and liquid are combined in a mixer and the resulting two-phase mixture enters the MHD generator. The MHD generator acts as a turbine and electric generator in one unit wherein the gas expands, drives the liquid across the magnetic field and thus generates electrical power. The gas and liquid are separated, and the available energy in the gas is recovered before the gas is exhausted to the atmosphere. Where the combustion gas contains sulfur, oxygen is bubbled through a side loop to remove sulfur therefrom as a concentrated stream of sulfur dioxide. The combustor is operated substoichiometrically to control the oxide level in the copper.

A peroxynitrite complex of copper: formation from a copper-nitrosyl complex, transformation to nitrite and exogenous phenol oxidative coupling or nitration.

Science.gov (United States)

Park, Ga Young; Deepalatha, Subramanian; Puiu, Simona C; Lee, Dong-Heon; Mondal, Biplab; Narducci Sarjeant, Amy A; del Rio, Diego; Pau, Monita Y M; Solomon, Edward I; Karlin, Kenneth D

2009-11-01

Reaction of nitrogen monoxide with a copper(I) complex possessing a tridentate alkylamine ligand gives a Cu(I)-(*NO) adduct, which when exposed to dioxygen generates a peroxynitrite (O=NOO(-))-Cu(II) species. This undergoes thermal transformation to produce a copper(II) nitrito (NO(2) (-)) complex and 0.5 mol equiv O(2). In the presence of a substituted phenol, the peroxynitrite complex effects oxidative coupling, whereas addition of chloride ion to dissociate the peroxynitrite moiety instead leads to phenol ortho nitration. Discussions include the structures (including electronic description) of the copper-nitrosyl and copper-peroxynitrite complexes and the formation of the latter, based on density functional theory calculations and accompanying spectroscopic data.

MICRO-MATERIAL HANDLING EMPLOYING E-BEAM GENERATED TOPOGRAPHIES OF COPPER AND ALUMINIUM

Directory of Open Access Journals (Sweden)

S. Matope

2012-01-01

Full Text Available

ENGLISH ABSTRACT: This paper focuses on the employment of copper and aluminium in a micro-material handling system actuated by Van der Waals forces. Electron beam (e-beam evaporator deposited both materials on a silicon substrate at a rate of 0.6-1.2 Angstroms/second, vacuum pressure between 2x10-6 and 3x10-6mbar, and at a current less than 10mA. A Veeco NanoMan V Atomic Force Microscope with Nanoscope version 7.3 software was used to analyse the root mean square (rms surface roughnesses of the generated topographies. Rumpf-Rabinovich’s rms formula was used to determine the Van der Waals forces exerted by the surfaces. It was synthesised that an e-beam deposition of 7 minutes’ duration on both materials produced an optimum micro-material handling solution, with copper suitable for the pick-up position and aluminium for the placement position.

AFRIKAANSE OPSOMMING: Die fokus van die artikel is op die gebruik van koper en aluminium in ‘n mikromateriaalhanteringstelsel, aangedryf deur Van der Waalskragte. ‘n Elektronstraal-verdamper plaas albei materiale op ‘n silikonbasis teen ‘n tempo van 0.6-1.2 Angstrom/sekonde, vakuumdruk tussen 2x10-6 en 3x10-6mbar, en teen ‘n stroom van minder as 10mA. ‘n Veeco NanoMan V Atomic Force mikroskoop, met Nanoscope 7.3 program-matuur is gebruik om die wortel-gemiddelde-kwadraat (wgk oppervlak ruheid van die gegenereerde topografieë te analiseer. Rumpf-Rabinovich se wgk-formule is gebruik om die Van der Waalskrage wat deur die oppervlaktes uitgeoefen word te bepaal. Dit is vasgestel dat ‘n elektronstraalafsetting van 7 minute op albei materiale die optimale materiaalhanteringoplossing bied, met koper geskik vir die optelposisie en aluminium vir die plasingsposisie.

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.

Implementing GIS regression trees for generating the spatial distribution of copper in Mediterranean environments

DEFF Research Database (Denmark)

Bou Kheir, Rania; Greve, Mogens Humlekrog; Deroin, Jean-Paul

2013-01-01

Soil contamination by heavy metals has become a widespread dangerous problem in many parts of the world, including the Mediterranean environments. This is closely related to the increase irrigation by waste waters, to the uncontrolled application of sewage sludge, industrial effluents, pesticides...... and fertilizers, to the rapid urbanization, to the atmospheric deposition of dust and aerosols, to the vehicular emissions and to many other negative human activities. In this context, this paper predicts the spatial distribution and concentration level of copper (Cu) in the 195km2 of Nahr el-Jawz watershed......H, hydraulical conductivity, organic matter, stoniness ratio, soil depth, slope gradient, slope aspect, slope curvature, land cover/use, distance to drainage line, proximity to roads, nearness to cities, and surroundings to waste areas) were generated from satellite imageries, Digital Elevation Models (DEMs...

Copper removal and microbial community analysis in single-chamber microbial fuel cell.

Science.gov (United States)

Wu, Yining; Zhao, Xin; Jin, Min; Li, Yan; Li, Shuai; Kong, Fanying; Nan, Jun; Wang, Aijie

2018-04-01

In this study, copper removal and electricity generation were investigated in a single-chamber microbial fuel cell (MFC). Result showed that copper was efficiently removed in the membrane-less MFC with removal efficiency of 98.3% at the tolerable Cu 2+ concentration of 12.5 mg L -1 , the corresponding open circuit voltage and maximum power density were 0.78 V and 10.2 W m -3 , respectively. The mechanism analysis demonstrated that microbial electrochemical reduction contributed to the copper removal with the products of Cu and Cu 2 O deposited at biocathode. Moreover, the microbial community analysis indicated that microbial communities changed with different copper concentrations. The dominant phyla were Proteobacteria and Bacteroidetes which could play key roles in electricity generation, while Actinobacteria and Acidobacteria were also observed which were responsible for Cu-resistant and copper removal. It will be of important guiding significance for the recovery of copper from low concentration wastewater through single-chamber MFC with simultaneous energy recovery. Copyright © 2018 Elsevier Ltd. All rights reserved.

Brazing copper to dispersion-strengthened copper

Science.gov (United States)

Ryding, David G.; Allen, Douglas; Lee, Richard H.

1996-11-01

The advanced photon source 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 than has ben possible to date. The beam is produced by using third- generation insertion devices in a 7-GeV electron/positron storage ring that is 1,104 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$_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, a dispersion-strengthened copper, is the desired design 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.

Copper and Copper Proteins in Parkinson’s Disease

Directory of Open Access Journals (Sweden)

Sergio Montes

2014-01-01

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

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

OpenAIRE

Redondo, Clara; Breslin, Carmel B.

2007-01-01

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

Adsorption of 1- and 2-butylimidazoles at the copper/air and steel/air interfaces studied by sum frequency generation vibrational spectroscopy.

Science.gov (United States)

Casford, Michael T L; Davies, Paul B

2012-07-24

The structure of thin films of 1- and 2-butylimidazoles adsorbed on copper and steel surfaces under air was examined using sum frequency generation (SFG) vibrational spectroscopy in the ppp and ssp polarizations. Additionally, the SFG spectra of both isomers were recorded at 55 °C at the liquid imidazole/air interface for reference. Complementary bulk infrared, reflection-absorption infrared spectroscopy (RAIRS), and Raman spectra of both imidazoles were recorded for assignment purposes. The SFG spectra in the C-H stretching region at the liquid/air interface are dominated by resonances from the methyl end group of the butyl side chain of the imidazoles, indicating that they are aligned parallel or closely parallel to the surface normal. These are also the most prominent features in the SFG spectra on copper and steel. In addition, both the ppp and ssp spectra on copper show resonances from the C-H stretching modes of the imidazole ring for both isomers. The ring C-H resonances are completely absent from the spectra on steel and at the liquid/air interface. The relative intensities of the SFG spectra can be interpreted as showing that, on copper, under air, both butylimidazoles are adsorbed with their butyl side chains perpendicular to the interface and with the ring significantly inclined away from the surface plane and toward the surface normal. The SFG spectra of both imidazoles on steel indicate an orientation where the imidazole rings are parallel or nearly parallel to the surface. The weak C-H resonances from the ring at the liquid/air interface suggest that the tilt angle of the ring from the surface normal at this interface is significantly greater than it is on copper.

Copper carrier protein in copper toxic sheep liver

Energy Technology Data Exchange (ETDEWEB)

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

1973-01-01

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

Copper stabilization in beneficial use of waterworks sludge and copper-laden electroplating sludge for ceramic materials.

Science.gov (United States)

Tang, Yuanyuan; Chan, Siu-Wai; Shih, Kaimin

2014-06-01

A promising strategy for effectively incorporating metal-containing waste materials into a variety of ceramic products was devised in this study. Elemental analysis confirmed that copper was the predominant metal component in the collected electroplating sludge, and aluminum was the predominant constituent of waterworks sludge collected in Hong Kong. The use of waterworks sludge as an aluminum-rich precursor material to facilitate copper stabilization under thermal conditions provides a promising waste-to-resource strategy. When sintering the mixture of copper sludge and the 900 °C calcined waterworks sludge, the CuAl2O4 spinel phase was first detected at 650 °C and became the predominant product phase at temperatures higher than 850 °C. Quantification of the XRD pattern using the Rietveld refinement method revealed that the weight of the CuAl2O4 spinel phase reached over 50% at 850 °C. The strong signals of the CuAl2O4 phase continued until the temperature reached 1150 °C, and further sintering initiated the generation of the other copper-hosting phases (CuAlO2, Cu2O, and CuO). The copper stabilization effect was evaluated by the copper leachability of the CuAl2O4 and CuO via the prolonged leaching experiments at a pH value of 4.9. The leaching results showed that the CuAl2O4 phase was superior to the CuAlO2 and CuO phases for immobilizing hazardous copper over longer leaching periods. The findings clearly indicate that spinel formation is the most crucial metal stabilization mechanism when sintering multiphase copper sludge with aluminum-rich waterworks sludge, and suggest a promising and reliable technique for reusing both types of sludge waste for ceramic materials. Copyright © 2013 Elsevier Ltd. All rights reserved.

Micronized copper wood preservatives: An efficiency and potential health risk assessment for copper-based nanoparticles

International Nuclear Information System (INIS)

Civardi, Chiara; Schwarze, Francis W.M.R.; Wick, Peter

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 nm–25 μm) 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, during decomposition of treated wood Cu-based NPs and/or their derivate may accumulate in the mycelium of Cu-tolerant fungi and end up in their spores that are dispersed into the environment. Inhaled Cu-loaded spores can cause harm and could become a potential risk for human health. We collected evidence and discuss the implications of the release of Cu-based NPs by wood-destroying fungi and highlight the exposure pathways and subsequent magnitude of health impact. - Highlights: • We compared copper particulate wood preservatives with conventional ones. • We assessed the fungicidal activity of particulate copper wood preservatives. • We reviewed the Cu-tolerance mechanisms of some wood-destroying fungi. • Fungi colonizing wood treated with particulate copper may release Cu-loaded spores. - We assess the fungicidal activity of particulate copper wood preservatives and their possible release in the air by Cu-tolerant wood-destroying fungi

Photophysical studies of the interactions of poly(amidoamine) generation zero (PAMAM G0) with copper and zinc ions

Energy Technology Data Exchange (ETDEWEB)

López-Cabaña, Z.E. [Laboratory of Asymmetric Synthesis, Chemistry Institute of Natural Resources, University of Talca (Chile); Valdés, O. [Nanobiotechnology Division at University of Talca, Fraunhofer Chile Research Foundation – Center for Systems Biotechnology, FCR-CSB, P.O. Box 747 Talca (Chile); Vergara, C.E. [Laboratory of Asymmetric Synthesis, Chemistry Institute of Natural Resources, University of Talca (Chile); Camarada, M.B. [Universidad Andrés Bello, Facultad de Biología, Center for Bioinformatics and Integrative Biology (CBIB), República 239, Santiago (Chile); Fundación Fraunhofer Chile Research, M. Sánchez Fontecilla 310 piso 14, Las Condes (Chile); Nachtigall, F.M. [Nanobiotechnology Division at University of Talca, Fraunhofer Chile Research Foundation – Center for Systems Biotechnology, FCR-CSB, P.O. Box 747 Talca (Chile); González-Nilo, F.D. [Universidad Andrés Bello, Facultad de Biología, Center for Bioinformatics and Integrative Biology (CBIB), República 239, Santiago (Chile); Fundación Fraunhofer Chile Research, M. Sánchez Fontecilla 310 piso 14, Las Condes (Chile); Santos, Leonardo S., E-mail: lssantos@utalca.cl [Laboratory of Asymmetric Synthesis, Chemistry Institute of Natural Resources, University of Talca (Chile); Nanobiotechnology Division at University of Talca, Fraunhofer Chile Research Foundation – Center for Systems Biotechnology, FCR-CSB, P.O. Box 747 Talca (Chile)

2015-08-15

This study reports the photophysical behavior of poly(amidoamine) generation zero (PAMAM G0) in the presence of Cu(II) and Zn(II) ions in aqueous solutions using absorption and fluorescence spectroscopy. Theoretical and experimental results confirmed the presence of a strong covalent metal–ligand interaction between PAMAM G0 and copper ion that favored the formation of a ligand–metal charge transfer band coordination complex. In the case of Zn(II), no complex formation with PAMAM G0 was registered. Structure analysis identified the presence of aggregate like PAMAM G0–Zn moieties that generated an enhancement in the fluorescence emission of PAMAM G0. - Highlights: • Photophysical behavior of PAMAM G0 dendrimer with Cu and Zn ions was studied. • Strong covalent metal–ligand interaction was confirmed between PAMAM G0–Cu(II). • No complex formation with PAMAM G0 was registered in the case of Zn(II). • Dendrimer aggregate generated an enhancement in fluorescence emission.

Photophysical studies of the interactions of poly(amidoamine) generation zero (PAMAM G0) with copper and zinc ions

International Nuclear Information System (INIS)

López-Cabaña, Z.E.; Valdés, O.; Vergara, C.E.; Camarada, M.B.; Nachtigall, F.M.; González-Nilo, F.D.; Santos, Leonardo S.

2015-01-01

This study reports the photophysical behavior of poly(amidoamine) generation zero (PAMAM G0) in the presence of Cu(II) and Zn(II) ions in aqueous solutions using absorption and fluorescence spectroscopy. Theoretical and experimental results confirmed the presence of a strong covalent metal–ligand interaction between PAMAM G0 and copper ion that favored the formation of a ligand–metal charge transfer band coordination complex. In the case of Zn(II), no complex formation with PAMAM G0 was registered. Structure analysis identified the presence of aggregate like PAMAM G0–Zn moieties that generated an enhancement in the fluorescence emission of PAMAM G0. - Highlights: • Photophysical behavior of PAMAM G0 dendrimer with Cu and Zn ions was studied. • Strong covalent metal–ligand interaction was confirmed between PAMAM G0–Cu(II). • No complex formation with PAMAM G0 was registered in the case of Zn(II). • Dendrimer aggregate generated an enhancement in fluorescence emission

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.

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

Science.gov (United States)

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

2017-08-01

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

Copper and copper-nickel-alloys - An overview

Energy Technology Data Exchange (ETDEWEB)

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

2004-07-01

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

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

Science.gov (United States)

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

2014-11-04

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

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

Science.gov (United States)

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

2018-02-01

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

Spectroscopic studies of copper enzymes

International Nuclear Information System (INIS)

Dooley, D.M.; Moog, R.; Zumft, W.; Koenig, S.H.; Scott, R.A.; Cote, C.E.; McGuirl, M.

1986-01-01

Several spectroscopic methods, including absorption, circular dichroism (CD), magnetic CD (MCD), X-ray absorption, resonance Raman, EPR, NMR, and quasi-elastic light-scattering spectroscopy, have been used to probe the structures of copper-containing amine oxidases, nitrite reductase, and nitrous oxide reductase. The basic goals are to determine the copper site structure, electronic properties, and to generate structure-reactivity correlations. Collectively, the results on the amine oxidases permit a detailed model for the Cu(II) sites in these enzymes to be constructed that, in turn, rationalizes the ligand-binding chemistry. Resonance Raman spectra of the phenylhydrazine and 2,4-dinitrophenyl-hydrazine derivatives of bovine plasma amine oxidase and models for its organic cofactor, e.g. pyridoxal, methoxatin, are most consistent with methoxatin being the intrinsic cofactor. The structure of the Cu(I) forms of the amine oxidases have been investigated by X-ray absorption spectroscopy (XAS); the copper coordination geometry is significantly different in the oxidized and reduced forms. Some anomalous properties of the amine oxidases in solution are explicable in terms of their reversible aggregation, which the authors have characterized via light scattering. Nitrite and nitrous oxide reductases display several novel spectral properties. The data suggest that new types of copper sites are present

Biokinetics of copper in black-banded rainbowfish (Melanotaenia nigrans) tolerant to elevated copper concentrations, using the radioisotope 64Cu

International Nuclear Information System (INIS)

Gale, S.; Jeffree, R.; Smith, S.; Lim, R.

2000-01-01

Full text: For over 40 years black-banded rainbowfish (Melanotaenia nigrans) living in the East Branch of the Finniss River, Northern Territory have been exposed to elevated copper concentrations due to mine waste from the Rum Jungle uranium/copper mine. In the 1970s prior to remediation of the mine, fish kills were observed along the length of the East Branch. While copper concentrations remain comparatively high (up to 2000 μg/L) in the East Branch since remediation of the mine site, M. nigrans have been observed in the area. It was, therefore, hypothesised that due to selective pressure of lethal exposure, the population of black-banded rainbowfish in the East Branch have developed a tolerance to elevated copper concentrations. This project aimed to demonstrate copper tolerance and evaluate possible mechanism(s). In May 2000, fish were collected from the East Branch (exposed fish) and from a catchment previously unexposed to elevated metal concentrations (reference fish). The 96-hour EC 50 , fish imbalance (i.e. the concentration of copper that affects 50% of fish over 96 hours) for the exposed fish was over 8 times higher than the reference fish. Using the radioisotope, 64 Cu, the biokinetics of newly accumulated copper was traced in exposed and reference fish at low and elevated copper concentrations. The uptake rate, and therefore body burden, were significantly (p=0.000) lower in exposed fish, at both low and elevated copper concentrations compared to reference fish. Possible mechanisms of reducing copper uptake will be discussed. Tolerance was not lost when fish were maintained in relatively low copper concentrations in the laboratory. Also, the two populations of fish were genetically dissimilar based on allozyme analysis, which suggests that the mechanism is genetically mediated. The outcome of this project will be important in assisting accurate risk assessment and the development of environmental management strategies for the conservation of biota. The

Copper-Sulfate Pentahydrate as a Product of the Waste Sulfuric Acid Solution Treatment

OpenAIRE

Marković, Radmila; Stevanović, Jasmina; Avramović, Ljiljana; Nedeljković, Dragutin; Jugović, Branimir; Stajić Trošić, Jasna; Gvozdenović, Milica M.

2012-01-01

The aim of this study is synthesis of copper-sulfate pentahydrate from the waste sulfuric acid solution-mother liquor generated during the regeneration process of copper bleed solution. Copper is removed from the mother liquor solution in the process of the electrolytic treatment using the insoluble lead anodes alloyed with 6 mass pct of antimony on the industrial-scale equipment. As the result of the decopperization process, copper is removed in the form of the cathode sludge and is precipit...

Recycling of copper used in fusion power plants

International Nuclear Information System (INIS)

Forty, C.B.A.; Butterworth, G.J.; Turner, A.D.; Junkison, A.J.

1997-04-01

One of the major safety and environmental advantages of fusion power is a limited waste management burden on future generations. In this connection, the ability to recycle end-of-service materials from fusion power plant is beneficial both in terms of the conservation of natural resources and the minimisation of the volumes of activated wastes. After 100 years, the residual activity of near-plasma copper components exceeds that permitted for free release or contact handling. The presence of silver as a common impurity in copper may exacerbate this problem, through generation of 108m Ag. Removal of the silver impurity in a separate refining step prior to use of the copper in a fusion plant obviates the problems associated with formation of 108m Ag. Two alternative desilveration processes have been demonstrated; one involving the segregation of silver as AgBr and the other the absorption of Ag + by ion exchange. The present study demonstrates that conventional electrorefining techniques can be adapted to recover used copper in a single refining stage, with sufficient decontamination to permit its reuse in fusion power plants or, with a second stage, unrestricted release. Shielding requirements for the processing of scrap copper in conventional hot cells indicate a decay storage period of 50-100 years. To maximise the cost of savings of reclamation over direct geological disposal, the activation products may be separated out and disposed of in a metallic form. A substantial reduction in the overall volume of active waste should thus be achievable, especially if supercompaction can be applied to the product. (Author)

Recycling of copper used in fusion power plants

International Nuclear Information System (INIS)

Butterworth, G.J.; Forty, C.B.A.

1998-01-01

One of the major safety and environmental advantages of fusion power is a limited waste management burden on future generations. In this connection, the ability to recycle end-of-service materials from fusion power plants is beneficial both in terms of the conservation of natural resources and the minimisation of the volume of activated wastes. After 100 years, the residual activity of near-plasma copper components exceeds that permitted for free release or contact handling. The presence of silver as a common impurity in copper may exacerbate this problem, through generation of 108m Ag. Removal of the silver impurity in a separate refining step prior to use of the copper in a fusion plant obviates the problems associated with formation of 108m Ag. Two alternative desilverisation processes have been demonstrated; one involving the segregation of silver as AgBr and the other the absorption of Ag + by ion exchange. The present study demonstrates that conventional electrorefining techniques can be adapted to recover used copper in a single refining stage, with sufficient decontamination to permit its reuse in fusion power plants or, with a second stage, unrestricted release. Shielding requirements for the processing of scrap copper in conventional hot cells indicate a decay storage period of 50-100 years. To maximise the cost savings of reclamation over direct geological disposal, the activation products may be separated out and disposed of in a metallic form. A substantial reduction in the overall volume of active waste should thus be achievable, especially if supercompaction can be applied to the product. (orig.)

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.)

Use of Fatty Acid Methyl Ester Profiles to Compare Copper-Tolerant and Copper-Sensitive Strains of Pantoea ananatis.

Science.gov (United States)

Nischwitz, C; Gitaitis, R; Sanders, H; Langston, D; Mullinix, B; Torrance, R; Boyhan, G; Zolobowska, L

2007-10-01

ABSTRACT A survey was conducted to evaluate differences in fatty acid methyl ester (FAME) profiles among strains of Pantoea ananatis, causal agent of center rot of onion (Allium cepa), isolated from 15 different onion cultivars in three different sites in Georgia. Differences in FAME composition were determined by plotting principal components (PCs) in two-dimensional plots. Euclidean distance squared (ED(2)) values indicated a high degree of similarity among strains. Plotting of PCs calculated from P. ananatis strains capable of growing on media amended with copper sulfate pentahydrate (200 mug/ml) indicated that copper-tolerant strains grouped into tight clusters separate from clusters formed by wild-type strains. However, unlike copper-sensitive strains, the copper-tolerant strains tended to cluster by location. A total of 80, 60, and 73% of the strains from Tift1, Tift2, and Tattnall, respectively, exhibited either confluent growth or partial growth on copper-amended medium. However, all strains were sensitive to a mixture of copper sulfate pentahydrate (200 mug/ml) and maneb (40 mug/ml). When copper-tolerant clones were analyzed and compared with their wild-type parents, in all cases the plotting of PCs developed from copper-tolerant clones formed tight clusters separate from clusters formed by the parents. Eigenvalues generated from these tests indicated that two components provided a good summary of the data, accounting for 98, 98, and 96% of the standardized variance for strains Pna 1-15B, Pna 1-12B, and Pna 2-5A, respectively. Furthermore, feature 4 (cis-9-hexadecenoic acid/2-hydroxy-13-methyltetradecanoic acid) and feature 7 (cis-9/trans-12/cis-7-octadecenoic acid) were the highest or second highest absolute values for PC1 in all three strains of the parents versus copper-tolerant clones, and hexadecanoic acid was the highest absolute value for PC2 in all three strains. Along with those fatty acids, dodecanoic acid and feature 3 (3-hydroxytetradecanoic

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

Science.gov (United States)

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

2011-11-15

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

Super-hydrophilic copper sulfide films as light absorbers for efficient solar steam generation under one sun illumination

Science.gov (United States)

Guo, Zhenzhen; Ming, Xin; Wang, Gang; Hou, Baofei; Liu, Xinghang; Mei, Tao; Li, Jinhua; Wang, Jianying; Wang, Xianbao

2018-02-01

Solar steam technology is one of the simplest, most direct and effective ways to harness solar energy through water evaporation. Here, we report the development using super-hydrophilic copper sulfide (CuS) films with double-layer structures as light absorbers for solar steam generation. In the double-layer structure system, a porous mixed cellulose ester (MCE) membrane is used as a supporting layer, which enables water to get into the CuS light absorbers through a capillary action to provide continuous water during solar steam generation. The super-hydrophilic property of the double-layer system (CuS/MCE) leads to a thinner water film close to the air-water interface where the surface temperature is sufficiently high, leading to more efficient evaporation (˜80 ± 2.5%) under one sun illumination. Furthermore, the evaporation efficiencies still keep a steady value after 15 cycles of testing. The super-hydrophilic CuS film is promising for practical application in water purification and evaporation as a light absorption material.

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.

Positive inotropic and vasodilator actions of milrinone in patients with severe congestive heart failure. Dose-response relationships and comparison to nitroprusside.

Science.gov (United States)

Jaski, B E; Fifer, M A; Wright, R F; Braunwald, E; Colucci, W S

1985-01-01

Milrinone is a potent positive inotropic and vascular smooth muscle-relaxing agent in vitro, and therefore, it is not known to what extent each of these actions contributes to the drug's hemodynamic effects in patients with heart failure. In 11 patients with New York Heart Association class III or IV congestive heart failure, incremental intravenous doses of milrinone were administered to determine the dose-response relationships for heart rate, systemic vascular resistance, and inotropic state, the latter measured by peak positive left ventricular derivative of pressure with respect to time (dP/dt). To clarify further the role of a positive inotropic action, the relative effects of milrinone and nitroprusside on left ventricular stroke work and dP/dt were compared in each patient at doses matched to cause equivalent reductions in mean arterial pressure or systemic vascular resistance, indices of left ventricular afterload. Milrinone caused heart rate, stroke volume, and dP/dt to increase, and systemic vascular resistance to decrease in a concentration-related manner. At the two lowest milrinone doses resulting in serum concentrations of 63 +/- 4 and 156 +/- 5 ng/ml, respectively, milrinone caused significant increases in stroke volume and dP/dt, but no changes in systemic vascular resistance or heart rate. At the maximum milrinone dose administered (mean serum concentration, 427 +/- 11 ng/ml), heart rate increased from 92 +/- 4 to 99 +/- 4 bpm (P less than 0.01), mean aortic pressure fell from 82 +/- 3 to 71 +/- 3 mmHg (P less than 0.01), right atrial pressure fell from 15 +/- 2 to 7 +/- 1 mmHg (P less than 0.005), left ventricular end-diastolic pressure fell from 26 +/- 3 to 18 +/- 3 (P less than 0.005), stroke volume index increased from 20 +/- 2 to 30 +/- 2 ml/m2 (P less than 0.005), stroke work index increased from 14 +/- 2 to 21 +/- 2 g X m/m2 (P less than 0.01), and dP/dt increased from 858 +/- 54 to 1,130 +/- 108 mmHg/s (P less than 0.005). When compared

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.

Active screen cage pulsed dc discharge for implanting copper in polytetrafluoroethylene (PTFE)

Science.gov (United States)

Zaka-ul-Islam, Mujahid; Naeem, Muhammad; Shafiq, Muhammad; Sitara; Jabbar Al-Rajab, Abdul; Zakaullah, Muhammad

2017-07-01

Polymers such as polytetrafluoroethylene (PTFE) are widely used in artificial organs where long-term anti-bacterial properties are required to avoid bacterial proliferation. Copper or silver ion implantation on the polymer surface is known as a viable method to generate long-term anti-bacterial properties. Here, we have tested pulsed DC plasma with copper cathodic cage for the PTFE surface treatment. The surface analysis of the treated specimens suggests that the surface, structural properties, crystallinity and chemical structure of the PTFE have been changed, after the plasma treatment. The copper release tests show that copper ions are released from the polymer at a slow rate and quantity of the released copper increases with the plasma treatment time.

Population growth rate and genetic variability of small and large populations of Red flour beetle (Tribolium castaneum) following multigenerational exposure to copper.

Science.gov (United States)

Laskowski, Ryszard; Radwan, Jacek; Kuduk, Katarzyna; Mendrok, Magdalena; Kramarz, Paulina

2015-07-01

We reared large (1000 individuals) and small (20 individuals) populations of Tribolium castaneum on diet contaminated with copper in order to determine if the size of a population affects its ability to adapt to adverse environmental conditions. After 10 generations, we used microsatellite markers to estimate and subsequently compare the genetic variability of the copper-treated populations with that of the control populations, which were reared on uncontaminated medium. Additionally, we conducted a full cross-factorial experiment which evaluated the effects of 10 generations of "pre-exposure" to copper on a population's fitness in control and copper-contaminated environments. In order to distinguish results potentially arising from genetic adaptation from those due to non-genetic effects associated to parental exposure to copper, we subjected also F11 generation, originating from parents not exposed to copper, to the same cross-factorial experiment. The effects of long-term exposure to copper depended on population size: the growth rates of small populations that were pre-exposed to copper were inhibited compared to those of small populations reared in uncontaminated environments. Large Cu-exposed populations had a higher growth rate in the F10 generation compared to the control groups, while the growth rate of the F11 generation was unaffected by copper exposure history. The only factor that had a significant effect on genetic variability was population size, but this was to be expected given the large difference in the number of individuals between large and small populations. Neither copper contamination nor its interaction with population size affected the number of microsatellite alleles retained in the F10 generation.

Geometric control of nuclearity in copper(I)/dioxygen chemistry.

Science.gov (United States)

Abe, Tsukasa; Morimoto, Yuma; Tano, Tetsuro; Mieda, Kaoru; Sugimoto, Hideki; Fujieda, Nobutaka; Ogura, Takashi; Itoh, Shinobu

2014-08-18

Copper(I) complexes supported by a series of N3-tridentate ligands bearing a rigid cyclic diamine framework such as 1,5-diazacyclooctane (L8, eight-membered ring), 1,4-diazacycloheptane (L7, seven-membered ring), or 1,4-diazacyclohexane (L6, six-membered ring) with a common 2-(2-pyridyl)ethyl side arm were synthesized and their reactivity toward O2 were compared. The copper(I) complex of L8 preferentially provided a mononuclear copper(II) end-on superoxide complex S as reported previously [Itoh, S., et al. J. Am. Chem. Soc. 2009, 131, 2788-2789], whereas a copper(I) complex of L7 gave a bis(μ-oxido)dicopper(III) complex O at a low temperature (-85 °C) in acetone. On the other hand, no such active-oxygen complex was detected in the oxygenation reaction of the copper(I) complex of L6 under the same conditions. In addition, O2-reactivity of the copper(I) complex supported by an acyclic version of the tridentate ligand (LA, PyCH2CH2N(CH3)CH2CH2CH2N(CH3)2; Py = 2-pyridyl) was examined to obtain a mixture of a (μ-η(2):η(2)-peroxido)dicopper(II) complex (S)P and a bis(μ-oxido)dicopper(III) complex O. Careful inspection of the crystal structures of copper(I) and copper(II) complexes and the redox potentials of copper(I) complexes has revealed important geometric effects of the supporting ligands on controlling nuclearity of the generated copper active-oxygen complexes.

Indirect determination of thiocyanate with ammonium sulfate and ethanol by extraction-flotation of copper.

Science.gov (United States)

Li, Q; Wei, W; Liu, Q

2000-10-01

A new method for the indirect determination of thiocyanate with ammonium sulfate and ethanol by extraction-flotation of copper in the presence of ascorbic acid is described. A small amount of Cu(II) is reduced to Cu(I) by ascorbic acid, then Cu(I) is precipitated with SCN-. In the course of phase separation of ethanol from water, the precipitated CuSCN stays in the interface of ethanol and water. A good linear relationship is observed between the flotation yield of Cu(II) and the amount of SCN-. Using 1.0 ml of 1 x 10(-3) M ascorbic acid solution, 50 micrograms of Cu(II), 3.5 g of (NH4)2SO4 and 3.0 ml of ethanol with a total volume of 10 ml, the concentration of thiocyanate could then be determined by determining the flotation yield of Cu(II). The detection limit for thiocyanate is 5 x 10(-5) M. Every parameter was optimized and the reaction mechanism was studied. The method is simple and rapid and it was successfully applied to the determination of thiocyanate in urine and saliva of smokers and non-smokers and in venous blood of patients infused with sodium nitroprusside.

Copper-polymer nanocomposites: An excellent and cost-effective biocide for use on antibacterial surfaces.

Science.gov (United States)

Tamayo, Laura; Azócar, Manuel; Kogan, Marcelo; Riveros, Ana; Páez, Maritza

2016-12-01

The development of polymer nanocomposites with antimicrobial properties has been a key factor for controlling or inhibiting the growth of microorganisms and preventing foodborne diseases and nosocomial infections. Commercially available antibacterial products based on silver-polymer are the most widely used despite the fact that copper is considerably less expensive. The incorporation of copper nanoparticles as antibacterial agents in polymeric matrices to generate copper-polymer nanocomposites have presented excellent results in inhibiting the growth of a broad spectrum of microorganisms. The potential applications in food packaging, medical devices, textiles and pharmaceuticals and water treatment have generated an increasing number of investigations on preparing copper based nanocomposites and alternative polymeric matrices, as potential hosts of nano-modifiers. This review presents a comprehensive compilation of previous published work on the subject, mainly related to the antimicrobial activity of copper polymer nanocomposites. Within all the phenomenology associated to antibacterial effects we highlight the possible mechanisms of action. We discuss the differences in the susceptibility of Gram negative and positive bacteria to the antibacterial activity of nanocomposites, and influencing factors. As well, the main applications of copper polymer-metal nanocomposites are described, considering their physical and chemical characteristics. Finally, some commercially available copper-polymer nanocomposites are described. Copyright © 2016 Elsevier B.V. All rights reserved.

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 ...

Effect of Minor Titanium Addition on Copper/Diamond Composites Prepared by Hot Forging

Science.gov (United States)

Yang, Fei; Sun, Wei; Singh, Ajit; Bolzoni, Leandro

2018-03-01

Copper/diamond composites have great potential to lead the next generation of advanced heat sink materials for use in high-power electronic devices and high-density integrated circuits because of their potential excellent properties of high thermal conductivity and close thermal expansion to the chip materials (e.g., Si, InP, GaAs). However, the poor wettability between copper and diamond presents a challenge for synthesizing copper/diamond composites with effective metallurgical bonding and satisfied thermal performance. In this article, copper/diamond composites were successfully prepared by hot forging of elemental copper and artificial diamond powders with small amounts (0 vol.%, 3 vol.% and 5 vol.%) of titanium additives. Microstructure observation and mechanical tests showed that adding minor titanium additions in the copper/diamond composite resulted in fewer cracks in the composites' microstructure and significantly improved the bonding between the copper and diamond. The strongest bonding strength was achieved for the copper/diamond composite with 3 vol.% titanium addition, and the possible reasons were discussed.

Reduction of radioactive backgrounds in electroformed copper for ultra-sensitive radiation detectors

Energy Technology Data Exchange (ETDEWEB)

Hoppe, E.W., E-mail: eric.hoppe@pnnl.gov [Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Aalseth, C.E.; Farmer, O.T.; Hossbach, T.W.; Liezers, M.; Miley, H.S.; Overman, N.R. [Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Reeves, J.H. [Reeves and Son LLC, 10 Albert Ave., Richland, WA 99352 (United States)

2014-11-11

Ultra-pure construction materials are required for the next generation of neutrino physics, dark matter and environmental science applications. These materials are also important for use in high-purity germanium spectrometers used in screening materials for radiopurity. The next-generation science applications require materials with radiopurity levels at or below 1 μBq/kg {sup 232}Th and {sup 238}U. Yet radiometric analysis lacks sensitivity below ∼10 μBq/kg for the U and Th decay chains. This limits both the selection of clean materials and the validation of purification processes. Copper is an important high-purity material for low-background experiments due to the ease with which it can be purified by electrochemical methods. Electroplating for purification into near-final shapes, known as electroforming, is one such method. Continued refinement of the copper electroforming process is underway, for the first time guided by an ICP-MS based assay method that can measure {sup 232}Th and {sup 238}U near the desired purity levels. An assay of electroformed copper at a μBq/kg level has been achieved and is described. The implications of electroformed copper at or better than this purity on next-generation low-background experiments are discussed.

Mechanisms underlying sodium nitroprusside-induced tolerance in the mouse aorta: Role of ROS and cyclooxygenase-derived prostanoids.

Science.gov (United States)

Diniz, Mariana C; Olivon, Vania C; Tavares, Lívia D; Simplicio, Janaina A; Gonzaga, Natália A; de Souza, Daniele G; Bendhack, Lusiane M; Tirapelli, Carlos R; Bonaventura, Daniella

2017-05-01

To determine the role of reactive oxygen species (ROS) on sodium nitroprusside (SNP)-induced tolerance. Additionally, we evaluated the role of ROS on NF-κB activation and pro-inflammatory cytokines production during SNP-induced tolerance. To induce in vitro tolerance, endothelium-intact or -denuded aortic rings isolated from male Balb-c mice were incubated for 15, 30, 45 or 60min with SNP (10nmol/L). Tolerance to SNP was observed after incubation of endothelium-denuded, but not endothelium-intact aortas for 60min with this inorganic nitrate. Pre-incubation of denuded rings with tiron (superoxide anion (O 2 - ) scavenger), and the NADPH oxidase inhibitors apocynin and atorvastatin reversed SNP-induced tolerance. l-NAME (non-selective NOS inhibitor) and l-arginine (NOS substrate) also prevented SNP-induced tolerance. Similarly, ibuprofen (non-selective cyclooxygenase (COX) inhibitor), nimesulide (selective COX-2 inhibitor), AH6809 (prostaglandin PGF 2 α receptor antagonist) or SQ29584 [PGH 2 /thromboxane TXA 2 receptor antagonist] reversed SNP-induced tolerance. Increased ROS generation was detected in tolerant arteries and both tiron and atorvastatin reversed this response. Tiron prevented tolerance-induced increase on O 2 - and hydrogen peroxide (H 2 O 2 ) levels. The increase onp65/NF-κB expression and TNF-α production in tolerant arteries was prevented by tiron. The major new finding of our study is that SNP-induced tolerance is mediated by NADPH-oxidase derived ROS and vasoconstrictor prostanoids derived from COX-2, which are capable of reducing the vasorelaxation induced by SNP. Additionally, we found that ROS mediate the activation of NF-κB and the production of TNF-α in tolerant arteries. These findings identify putative molecular mechanisms whereby SNP induces tolerance in the vasculature. Copyright © 2017 Elsevier Inc. All rights reserved.

Effect of isoproterenol, phenylephrine, and sodium nitroprusside on fundus pulsations in healthy volunteers.

Science.gov (United States)

Schmetterer, L; Wolzt, M; Salomon, A; Rheinberger, A; Unfried, C; Zanaschka, G; Fercher, A F

1996-03-01

Recently a laser interferometric method for topical measurement of fundus pulsations has been developed. Fundus pulsations in the macular region are caused by the inflow and outflow of blood into the choroid. The purpose of this work was to study the influence of a peripheral vasoconstricting (the alpha 1 adrenoceptor agonist phenylephrine), a predominantly positive inotropic (the non-specific beta adrenoceptor agonist isoproterenol), and a non-specific vasodilating (sodium nitroprusside) model drug on ocular fundus pulsations to determine reproducibility and sensitivity of the method. In a double masked randomised crossover study the drugs were administered in stepwise increasing doses to 10 male and nine female healthy volunteers. Systemic haemodynamic variables and fundus pulsations were measured at all infusion steps. Fundus pulsation increased during infusion of isoproterenol with statistical significance versus baseline at the lowest dose of 0.1 microgram/min. Neither peripheral vasoconstriction nor peripheral vasodilatation affected the ocular fundus pulsations. Measurements of fundus pulsations is a highly reproducible method in healthy subjects with low ametropy. Changes of local pulsatile ocular blood flow were detectable with our method following the infusion of isoproterenol. As systemic pharmacological vasodilatation or vasoconstriction did not change fundus pulsations, further experimental work has to be done to evaluate the sensitivity of the laser interferometric fundus pulsation measurement in various eye diseases.

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.

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

International Nuclear Information System (INIS)

Nevaeva, L.M.

1983-01-01

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

In vitro studies of copper release from powder particles in synthetic biological media

International Nuclear Information System (INIS)

Midander, Klara; Wallinder, Inger Odnevall; Leygraf, Christofer

2007-01-01

The aim of this paper is to provide quantitative data on copper release from powder particles of different copper materials, including artificial copper patina, Cu 2 O and metallic Cu, when exposed to different synthetic biological media to simulate an inhalation scenario and/or skin contact. Generated data may contribute in risk assessment of potential health effects following exposure to and handling of various copper materials. All tests were performed in vitro to determine total copper concentrations, release rates of total copper, and to elucidate its time-dependence. The copper release process was interpreted in terms of specific surface area, surface morphology-, and composition. All powder materials show a time-dependent release process with total copper release rates less than 3 μg/cm 2 per hour at steady state conditions, for all media investigated. The importance of using relevant test media when simulating different interstitial lung conditions and difficulties encountered when comparing powder particles of essentially different properties are thoroughly discussed. - Copper release rates from particles are essential to assess potential health aspects

Transgenic Mice Expressing Yeast CUP1 Exhibit Increased Copper Utilization from Feeds

Science.gov (United States)

Chen, Zhenliang; Liao, Rongrong; Zhang, Xiangzhe; Wang, Qishan; Pan, Yuchun

2014-01-01

Copper is required for structural and catalytic properties of a variety of enzymes participating in many vital biological processes for growth and development. Feeds provide most of the copper as an essential micronutrient consumed by animals, but inorganic copper could not be utilized effectively. In the present study, we aimed to develop transgenic mouse models to test if copper utilization will be increased by providing the animals with an exogenous gene for generation of copper chelatin in saliva. Considering that the S. cerevisiae CUP1 gene encodes a Cys-rich protein that can bind copper as specifically as copper chelatin in yeast, we therefore constructed a transgene plasmid containing the CUP1 gene regulated for specific expression in the salivary glands by a promoter of gene coding pig parotid secretory protein. Transgenic CUP1 was highly expressed in the parotid and submandibular salivary glands and secreted in saliva as a 9-kDa copper-chelating protein. Expression of salivary copper-chelating proteins reduced fecal copper contents by 21.61% and increased body-weight by 12.97%, suggesting that chelating proteins improve the utilization and absorbed efficacy of copper. No negative effects on the health of the transgenic mice were found by blood biochemistry and histology analysis. These results demonstrate that the introduction of the salivary CUP1 transgene into animals offers a possible approach to increase the utilization efficiency of copper and decrease the fecal copper contents. PMID:25265503

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

Directory of Open Access Journals (Sweden)

Zhengqi Guo

2016-04-01

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

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

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Potassium sodium copper chloropyhllin (chlorophyllin-copper complex). 73.1125 Section 73.1125 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT....1125 Potassium sodium copper chloropyhllin (chlorophyllin-copper complex). (a) Identity. (1) The color...

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

Science.gov (United States)

2010-04-01

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

Chemistry management of generator stator water system

International Nuclear Information System (INIS)

Sankar, N.; Santhanam, V.S.; Ayyar, S.R.; Umapathi, P.; Jeena, P.; Hari Krishna, K.; Rajendran, D.

2015-01-01

Chemistry management of water cooled turbine generators with hollow copper conductors is very essential to avoid possible re-deposition of released copper oxides on stator windings, which otherwise may cause flow restrictions by partial plugging of copper hollow conductors and impair cooling. The phenomenon which is of more concern is not strictly of corrosion failure, but the consequences caused by the re-deposition of copper oxides that were formed by reaction of copper with oxygen. There were also some Operating experiences (OE) related to Copper oxide fouling in the system resulting shut down/off-line of plants. In Madras Atomic Power Station (MAPS), the turbine generator stator windings are of Copper material and cooled by demineralized water passing through the hollow conductors. The heated water from the stator is cooled by process water. A part of the stator water is continuously passed through a mixed bed polisher to remove any soluble ionic contaminants to maintain the purity of system water and also maintain copper content as low as possible to avoid possible re-deposition of released copper oxides on stator windings. The chemistry regime employed is neutral water with dissolved oxygen content between 1000-2000 ppb. Chemistry management of Stator water system was reviewed to know its effectiveness. Detailed chemical analyses of the spent resins from the polishing unit were carried out in various campaigns which indicated only part exhaustion of the polishing unit resins and reasonably low levels of copper entrapment in the resins, thus highlighting the effectiveness of the in-practice chemistry regime. (author)

Laser ablated copper plasmas in liquid and gas ambient

Science.gov (United States)

Kumar, Bhupesh; Thareja, Raj K.

2013-05-01

The dynamics of copper ablated plasma plumes generated using laser ablation of copper targets in both liquid (de-ionized water) and gas (air) ambients is reported. Using time and space resolved visible emission spectroscopy (450-650 nm), the plasma plumes parameters are investigated. The electron density (ne) determined using Stark broadening of the Cu I (3d104d1 2D3/2-3d104p1 2P3/2 at 521.8 nm) line is estimated and compared for both plasma plumes. The electron temperature (Te) was estimated using the relative line emission intensities of the neutral copper transitions. Field emission scanning electron microscopy and energy dispersive x-ray spectral analysis of the ablated copper surface indicated abundance of spherical nanoparticles in liquid while those in air are amalgamates of irregular shapes. The nanoparticles suspended in the confining liquid form aggregates and exhibit a surface plasmon resonance at ˜590 nm.

Development of pits and cones on ion bombarded copper

International Nuclear Information System (INIS)

Tanovic, L.A.; Carter, G.; Nobes, M.J.; Whitton, I.L.; Williams, J.S.

1980-01-01

The formation of pits and cones on Ar ion bombarded copper has been studied. Carefully polished surfaces of large grained 99.999% pure copper crystals have been bombarded at normal incidence with 40 keV argon ions. The cone formation has been investigated for annealed and non-annealed crystals at room temperature and at 30 K and in the case of monocrystal and polycrystal samples. Although in the most other studies the presence of impurities is as a necessary condition for generation of cones and pits the obtained experimental results show that under certain conditions these features are formed on clean surfaces. It is shown that the dominant parameter in the production of cones on copper is the crystal orientation [ru

Disposal and improvement of contaminated by waste extraction of copper mining in chile

Science.gov (United States)

Naranjo Lamilla, Pedro; Blanco Fernández, David; Díaz González, Marcos; Robles Castillo, Marcelo; Decinti Weiss, Alejandra; Tapia Alvarez, Carolina; Pardo Fabregat, Francisco; Vidal, Manuel Miguel Jordan; Bech, Jaume; Roca, Nuria

2016-04-01

This project originated from the need of a mining company, which mines and processes copper ore. High purity copper is produced with an annual production of 1,113,928 tons of concentrate to a law of 32%. This mining company has generated several illegal landfills and has been forced by the government to make a management center Industrial Solid Waste (ISW). The forecast volume of waste generated is 20,000 tons / year. Chemical analysis established that the studied soil has a high copper content, caused by nature or from the spread of contaminants from mining activities. Moreover, in some sectors, soil contamination by mercury, hydrocarbons and oils and fats were detected, likely associated with the accumulation of waste. The waters are also impacted by mining industrial tasks, specifically copper ores, molybdenum, manganese, sulfates and have an acidic pH. The ISW management center dispels the pollution of soil and water and concentrating all activities in a technically suitable place. In this center the necessary guidelines for the treatment and disposal of soil contamination caused by uncontrolled landfills are given, also generating a leachate collection system and a network of fluid monitoring physicochemical water quality and soil environment. Keywords: Industrial solid waste, soil contamination, Mining waste

Antwerp Copper Plates

DEFF Research Database (Denmark)

Wadum, Jørgen

1999-01-01

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

Response of copepods to elevated pCO2 and environmental copper as co-stressors--a multigenerational study.

Directory of Open Access Journals (Sweden)

Susan C Fitzer

Full Text Available We examined the impacts of ocean acidification and copper as co-stressors on the reproduction and population level responses of the benthic copepod Tisbe battagliai across two generations. Naupliar production, growth, and cuticle elemental composition were determined for four pH values: 8.06 (control; 7.95; 7.82; 7.67, with copper addition to concentrations equivalent to those in benthic pore waters. An additive synergistic effect was observed; the decline in naupliar production was greater with added copper at decreasing pH than for decreasing pH alone. Naupliar production modelled for the two generations revealed a negative synergistic impact between ocean acidification and environmentally relevant copper concentrations. Conversely, copper addition enhanced copepod growth, with larger copepods produced at each pH compared to the impact of pH alone. Copepod digests revealed significantly reduced cuticle concentrations of sulphur, phosphorus and calcium under decreasing pH; further, copper uptake increased to toxic levels that lead to reduced naupliar production. These data suggest that ocean acidification will enhance copper bioavailability, resulting in larger, but less fecund individuals that may have an overall detrimental outcome for copepod populations.

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

DEFF Research Database (Denmark)

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

2005-01-01

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

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

International Nuclear Information System (INIS)

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

2015-01-01

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

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

OpenAIRE

Langley, Adrian; Dameron, Charles T.

2013-01-01

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

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.

Effect of sodium nitroprusside-induced hypotension on the blood flow in subcutaneous and intramuscular BT4An tumors and normal tissues in rats

International Nuclear Information System (INIS)

Krossnes, Baard Kronen; Mella, Olav; Tyssebotn, Ingvald

1996-01-01

Purpose: To examine the effect of infusion of the vasodilator sodium nitroprusside (SNP) on the blood flow in normal tissues and BT 4 An tumors growing subcutaneously or intramusculary in BD IX rats. Methods and Materials: Sodium nitroprusside was given as a continuous intravenous infusion to keep the mean arterial pressure stable at 60 mmHg. The cardiac output, organ blood flow, and perfusion of the BT 4 An tumors were measured by injection of radiolabelled microspheres at control conditions and after 20 min SNP infusion in each animal. Two series of experiments were performed with two anesthetics with different mechanisms of action, Inactin and the midazolam-fentanyl-fluanisone combination (MFF), to secure reliable conclusions. Results: Cardiac output, heart rate, and blood flow to the skeletal muscles, heart, and liver increased during SNP infusion in either anesthetic group. In the kidneys and particularly in the skin, decreased blood flow by SNP was observed. When located subcutaneously on the foot, the blood flow in the tumor fell to 23.4% and 21.4% of the control values in the MFF- and Inactin-anesthetized animals, respectively. This was accompanied by a similar fall in the blood flow in the foot (tumor bed) itself. In the intramuscular tumor the blood flow fell to 24.8% of the control value in the MFF group, whereas the corresponding figure was 36.2% in the Inactin group. In the surrounding muscle (tumor bed) the blood flow increased significantly, most pronounced in the MFF experiment, where it was tripled. Conclusion: The fall in the tumor perfusion by SNP may be exploited therapeutically to increase the tumor temperature during hyperthermia. Predominant heating of the tumor compared to the tumor bed can be expected if the tumor is growing in or near skeletal muscles

Fs–ns double-pulse Laser Induced Breakdown Spectroscopy of copper-based-alloys: Generation and elemental analysis of nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Guarnaccio, A.; Parisi, G.P.; Mollica, D. [CNR-ISM, U.O.S. Tito Scalo, Zona Industriale, 85050 Tito Scalo, PZ (Italy); De Bonis, A. [CNR-ISM, U.O.S. Tito Scalo, Zona Industriale, 85050 Tito Scalo, PZ (Italy); Dipartimento di Scienze, Università degli Studi della Basilicata, Via dell' Ateneo Lucano 10, 85100 Potenza (Italy); Teghil, R. [Dipartimento di Scienze, Università degli Studi della Basilicata, Via dell' Ateneo Lucano 10, 85100 Potenza (Italy); Santagata, A. [CNR-ISM, U.O.S. Tito Scalo, Zona Industriale, 85050 Tito Scalo, PZ (Italy)

2014-11-01

Evolution of nanoparticles ejected during ultra-short (250 fs) laser ablation of certified copper alloys and relative calibration plots of a fs–ns double-pulse Laser Induced Breakdown Spectroscopy orthogonal configuration is presented. All work was performed in air at atmospheric pressure using certified copper-based-alloy samples irradiated by a fs laser beam and followed by a delayed perpendicular ns laser pulse. In order to evaluate possible compositional changes of the fs induced nanoparticles, it was necessary to consider, for all samples used, comparable features of the detected species. With this purpose the induced nanoparticles black-body-like emission evolution and their relative temperature decay have been studied. These data were exploited for defining the distance between the target surface and the successive ns laser beam to be used. The consequent calibration plots of minor constituents (i.e. Sn, Pb and Zn) of the certified copper-based-alloy samples have been reported by taking into account self-absorption effects. The resulting linear regression coefficients suggest that the method used, for monitoring and ruling the fs laser induced nanoparticles, could provide a valuable approach for establishing the occurrence of potential compositional changes of the detected species. All experimental data reveal that the fs laser induced nanoparticles can be used for providing a coherent composition of the starting target. In the meantime, the fs–ns double-pulse Laser Induced Breakdown Spectroscopy orthogonal configuration here used can be considered as an efficient technique for compositional determination of the nanoparticles ejected during ultra-short laser ablation processes. - Highlights: • Laser induced NP continuum black-body-like emission was used for T determination. • Invariable composition of generated NPs was assumed in the range of 20 μs. • Fs-ns DP-LIBS was employed for the compositional characterization of NPs. • NPs obtained by fs

Production of brown and black pigments by using flotation waste from copper slag.

Science.gov (United States)

Ozel, Emel; Turan, Servet; Coruh, Semra; Ergun, Osman Nuri

2006-04-01

One of the major problems in copper-producing countries is the treatment of the large amount of copper slag or copper flotation waste generated from copper slag which contains significant amounts of heavy metals such as Cu, Zn, Pb and Co. Dumping or disposal of such large quantities of flotation waste from copper slag causes environmental and space problems. In this study, the treatment of flotation waste from copper slag by a thermal method and its use as an iron source in the production of inorganic brown and black pigments that are used in the ceramic industry were investigated. The pigments were produced by calcining different amounts of flotation waste and chromite, Cr2O3, ZnO and CoO mixtures. The pigments obtained were added to transparent ceramic glazes and porcelainized tile bodies. Their colours were defined by L*a*b* measurements with a spectrophotometer. The results showed that flotation waste from copper slag could be used as an iron source to produce brown and black pigments in both ceramic body and glazes.

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

NARCIS (Netherlands)

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

2011-01-01

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

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

Science.gov (United States)

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

2015-01-01

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

Canine Copper-Associated Hepatitis

NARCIS (Netherlands)

Dirksen, Karen; Fieten, Hille

2017-01-01

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

Gallium and copper radiopharmaceutical chemistry

International Nuclear Information System (INIS)

Green, M.A.; John, E.K.; Barnhart, A.J.

1990-01-01

Several isotopes of gallium and copper exhibit nuclear properties that make them attractive for applications in nuclear medicine, most notably Ga-67, Ga-68, Cu-67 and Cu-62. Of these, gamma-emitting Ga-67 has historically found the greatest clinical use, based on the observation that tracer gallium(III) citrate rapidly produces Ga-67 transferrin upon intravenous injection and then slowly affords selective Ga-67 localization in sites of abscess and certain tumors. Copper-67 has received attention as a potential label for tissue-selective monoclonal antibodies, since its associated γ-photons can be used for external imaging and its β - -emissions could be used for radiation therapy. Positron-emitting gallium-68 and copper-62, being available from parent/daughter generator systems, have attracted interest as potential labels for radiopharmaceuticals used in positron emission tomography (PET) because they could reduce the dependence of this imaging technology on hospital-based cyclotrons. The 10 min. half-life of Cu-62 is particularly well-suited to the time frame of PET studies of tissue perfusion, an application for which Cu(II)-bis(thiosemicarbazone) derivatives appear promising. The 68 min. half-life of Ga-68 makes it appropriate for PET studies over longer imaging time spans

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

Science.gov (United States)

Kesler, Stephen E.; Wilkinson, Bruce H.

2008-03-01

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

Effects of sodium nitroprusside on mouse erythrocyte catalase activity and malondialdehyde status.

Science.gov (United States)

Sani, Mamane; Sebai, Hichem; Refinetti, Roberto; Mondal, Mohan; Ghanem-Boughanmi, Néziha; Boughattas, Naceur A; Ben-Attia, Mossadok

2016-01-01

There is controversy about the anti- or pro-oxidative effects of the nitric oxide (NO)-donor sodium nitroprusside (SNP). Hence, the activity of the antioxidant enzyme catalase (CAT) and the status of malondialdehyde (MDA) were investigated after a 2.5 mg/kg dose of SNP had been i.p. administered to different and comparable groups of mice (n = 48). The drug was administered at two different circadian times (1 and 13 h after light onset [HALO]). There were, irrespectively of sampling time, no significant differences in the means of CAT activity and MDA status between control and SNP-treated groups, no matter the treatment time. However, CAT activity was significantly (Student's t-test, p < 0.001) increased 1 h following SNP administration at 1 HALO, whereas the significant (p < 0.001) increase in the enzyme activity was found only 3 h after injection at 13 HALO. The drug dosing either at 1 or 13 HALO resulted in no significant differences of MDA status between control and treated groups regardless to the sampling time. Two-way analysis of variance (ANOVA) detected a significant (F0.05(7,88)= 5.3; p < 0.0006) interaction between sampling time and treatment in mice injected at 1 HALO, suggesting the influence of treatment on sampling-time-related changes in CAT activity. However, ANOVA validated no interaction between the two factors in mice treated at 13 HALO, illustrating that the sampling-time differences in enzyme activity were greater. Furthermore, two-way ANOVA revealed no interaction in the variation of MDA status in animals treated either at 1 or 13 HALO. This study indicates that SNP significantly affected the anti-oxidant system.

Laser ablated copper plasmas in liquid and gas ambient

Energy Technology Data Exchange (ETDEWEB)

Kumar, Bhupesh; Thareja, Raj K. [Department of Physics, Indian Institute of Technology Kanpur, Kanpur 208 016 (India)

2013-05-15

The dynamics of copper ablated plasma plumes generated using laser ablation of copper targets in both liquid (de-ionized water) and gas (air) ambients is reported. Using time and space resolved visible emission spectroscopy (450-650 nm), the plasma plumes parameters are investigated. The electron density (n{sub e}) determined using Stark broadening of the Cu I (3d{sup 10}4d{sup 1} {sup 2}D{sub 3/2}-3d{sup 10}4p{sup 1} {sup 2}P{sub 3/2} at 521.8 nm) line is estimated and compared for both plasma plumes. The electron temperature (T{sub e}) was estimated using the relative line emission intensities of the neutral copper transitions. Field emission scanning electron microscopy and energy dispersive x-ray spectral analysis of the ablated copper surface indicated abundance of spherical nanoparticles in liquid while those in air are amalgamates of irregular shapes. The nanoparticles suspended in the confining liquid form aggregates and exhibit a surface plasmon resonance at ∼590 nm.

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

Science.gov (United States)

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

2017-08-01

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

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....

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

NARCIS (Netherlands)

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

1991-01-01

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

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

NARCIS (Netherlands)

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

1991-01-01

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

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

International Nuclear Information System (INIS)

McCormick, Stephen F.

2016-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2016-03-25

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

Anticancer activity of Ficus religiosa engineered copper oxide nanoparticles

International Nuclear Information System (INIS)

Sankar, Renu; Maheswari, Ramasamy; Karthik, Selvaraju; Shivashangari, Kanchi Subramanian; Ravikumar, Vilwanathan

2014-01-01

The design, synthesis, characterization and application of biologically synthesized nanomaterials have become a vital branch of nanotechnology. There is a budding need to develop a method for environmentally benign metal nanoparticle synthesis, that do not use toxic chemicals in the synthesis protocols to avoid adverse effects in medical applications. Here, it is a report on an eco-friendly process for rapid synthesis of copper oxide nanoparticles using Ficus religiosa leaf extract as reducing and protecting agent. The synthesized copper oxide nanoparticles were confirmed by UV–vis spectrophotometer, absorbance peaks at 285 nm. The copper oxide nanoparticles were analyzed with field emission-scanning electron microscope (FE-SEM), Fourier transform infrared (FT-IR) spectroscopy, dynamic light scattering (DLS) and X-ray diffraction (XRD) spectrum. The FE-SEM and DLS analyses exposed that copper oxide nanoparticles are spherical in shape with an average particle size of 577 nm. FT-IR spectral analysis elucidates the occurrence of biomolecules required for the reduction of copper oxide ions. Zeta potential studies showed that the surface charge of the formed nanoparticles was highly negative. The XRD pattern revealed that synthesized nanoparticles are crystalline in nature. Further, biological activities of the synthesized nanoparticles were confirmed based on its stable anti-cancer effects. The apoptotic effect of copper oxide nanoparticles is mediated by the generation of reactive oxygen species (ROS) involving the disruption of mitochondrial membrane potential (Δψm) in A549 cells. The observed characteristics and results obtained in our in vitro assays suggest that the copper nanoparticles might be a potential anticancer agent. - Highlights: • Biogenic synthesis of copper oxide nanoparticles by leaf extract of Ficus religiosa • Characterized via UV–vis, FT-IR, DLS, FE-SEM with EDAX and XRD • Protein may act as an encapsulating, reducing and stabilizing

Anticancer activity of Ficus religiosa engineered copper oxide nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Sankar, Renu; Maheswari, Ramasamy; Karthik, Selvaraju [Department of Biochemistry, School of Life Sciences, Bharathidasan University, Tiruchirappalli 620 024, Tamilnadu (India); Shivashangari, Kanchi Subramanian, E-mail: shivashangari@gmail.com [Regional Forensic Science Laboratory, Tiruchirapalli, Tamilnadu (India); Ravikumar, Vilwanathan, E-mail: ravikumarbdu@gmail.com [Department of Biochemistry, School of Life Sciences, Bharathidasan University, Tiruchirappalli 620 024, Tamilnadu (India)

2014-11-01

The design, synthesis, characterization and application of biologically synthesized nanomaterials have become a vital branch of nanotechnology. There is a budding need to develop a method for environmentally benign metal nanoparticle synthesis, that do not use toxic chemicals in the synthesis protocols to avoid adverse effects in medical applications. Here, it is a report on an eco-friendly process for rapid synthesis of copper oxide nanoparticles using Ficus religiosa leaf extract as reducing and protecting agent. The synthesized copper oxide nanoparticles were confirmed by UV–vis spectrophotometer, absorbance peaks at 285 nm. The copper oxide nanoparticles were analyzed with field emission-scanning electron microscope (FE-SEM), Fourier transform infrared (FT-IR) spectroscopy, dynamic light scattering (DLS) and X-ray diffraction (XRD) spectrum. The FE-SEM and DLS analyses exposed that copper oxide nanoparticles are spherical in shape with an average particle size of 577 nm. FT-IR spectral analysis elucidates the occurrence of biomolecules required for the reduction of copper oxide ions. Zeta potential studies showed that the surface charge of the formed nanoparticles was highly negative. The XRD pattern revealed that synthesized nanoparticles are crystalline in nature. Further, biological activities of the synthesized nanoparticles were confirmed based on its stable anti-cancer effects. The apoptotic effect of copper oxide nanoparticles is mediated by the generation of reactive oxygen species (ROS) involving the disruption of mitochondrial membrane potential (Δψm) in A549 cells. The observed characteristics and results obtained in our in vitro assays suggest that the copper nanoparticles might be a potential anticancer agent. - Highlights: • Biogenic synthesis of copper oxide nanoparticles by leaf extract of Ficus religiosa • Characterized via UV–vis, FT-IR, DLS, FE-SEM with EDAX and XRD • Protein may act as an encapsulating, reducing and stabilizing

Copper wire bonding

CERN Document Server

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

2014-01-01

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

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

Institute of Scientific and Technical Information of China (English)

2012-01-01

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

Spill-Overs of a Resource Boom: Evidence from Zambian Copper Mines

OpenAIRE

Alexander Lippert

2014-01-01

Do local populations benefit from resource booms? How strong are market linkages between the mining sector and the regional economy? This paper exploits exogenous variation in mine-level production volumes generated by the recent copper boom in Zambia to shed light on these questions. Using a novel dataset, I find robust evidence that an increase in local copper production improves living standards in the surroundings of the mines even for households not directy employed in the mining sector:...

Low-cost optical fabrication of flexible copper electrode via laser-induced reductive sintering and adhesive transfer

Science.gov (United States)

Back, Seunghyun; Kang, Bongchul

2018-02-01

Fabricating copper electrodes on heat-sensitive polymer films in air is highly challenging owing to the need of expensive copper nanoparticles, rapid oxidation of precursor during sintering, and limitation of sintering temperature to prevent the thermal damage of the polymer film. A laser-induced hybrid process of reductive sintering and adhesive transfer is demonstrated to cost-effectively fabricate copper electrode on a polyethylene film with a thermal resistance below 100 °C. A laser-induced reductive sintering process directly fabricates a high-conductive copper electrode onto a glass donor from copper oxide nanoparticle solution via photo-thermochemical reduction and agglomeration of copper oxide nanoparticles. The sintered copper patterns were transferred in parallel to a heat-sensitive polyethylene film through self-selective surface adhesion of the film, which was generated by the selective laser absorption of the copper pattern. The method reported here could become one of the most important manufacturing technologies for fabricating low-cost wearable and disposable electronics.

Control of Compact-Toroid Characteristics by External Copper Shell

Science.gov (United States)

Matsumoto, T.; Sekiguchi, J.; Asai, T.; Gota, H.; Roche, T.; Allfrey, I.; Cordero, M.; Garate, E.; Kinley, J.; Valentine, T.; Waggoner, W.; the TAE Team

2015-11-01

A collaborative research project by Tri Alpha Energy and Nihon University has been conducted for several years, which led to the development of a new compact toroid (CT) injector for efficient FRC particle refueling in the C-2U experiment. The CT is formed by a magnetized coaxial plasma gun (MCPG), consisting of coaxial cylindrical electrodes. In CT formation via MCPG, the magnetic helicity content of the generated CT is one of the critical parameters. A bias coil is inserted into the inner electrode to generate a poloidal flux. The resultant bias magnetic field is spread out of MCPG with time due to its low-frequency bias current. To obtain a more effectively distributed bias magnetic field as well as to improve the voltage breakdown between electrodes, the MCPG incorporates a novel ~ 1 mm thick copper shell mounted outside of the outer electrode. This allows for reliable and controlled operation and more robust CT generation. A detailed discussion of the copper shell and experimental test results will be presented.

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

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

Science.gov (United States)

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

2018-01-01

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

Condensation on Superhydrophobic Copper Oxide Nanostructures

OpenAIRE

Enright, Ryan; Miljkovic, Nenad; Dou, Nicholas; Nam, Youngsuk; Wang, Evelyn N.

2013-01-01

Condensation is an important process in both emerging and traditional power generation and water desalination technologies. Superhydrophobic nanostructures promise enhanced condensation heat transfer by reducing the characteristic size of departing droplets via a surface-tension-driven mechanism [1]. In this work, we investigated a scalable synthesis technique to produce oxide nanostructures on copper surfaces capable of sustaining superhydrophobic condensation and characterized the growth an...

Neuroprotective effects of curcumin and highly bioavailable curcumin on oxidative stress induced by sodium nitroprusside in rat striatal cell culture.

Science.gov (United States)

Nazari, Qand Agha; Kume, Toshiaki; Izuo, Naotaka; Takada-Takatori, Yuki; Imaizumi, Atsushi; Hashimoto, Tadashi; Izumi, Yasuhiko; Akaike, Akinori

2013-01-01

Curcumin, a polyphenolic compound extracted from Curcuma longa, has several pharmacological activities such as anticancer, anti-inflammatory, and antioxidant effects. The purpose of this study was to investigate the protective effects of curcumin and THERACURMIN, a highly bioavailable curcumin, against sodium nitroprusside (SNP)-induced oxidative damage in primary striatal cell culture. THERACURMIN as well as curcumin significantly prevented SNP-induced cytotoxicity. To elucidate the cytoprotective effects of curcumin and THERACURMIN, we measured the intracellular glutathione level in striatal cells. Curcumin and THERACURMIN significantly elevated the glutathione level, which was decreased by treatment with SNP. Moreover, curcumin showed potent 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging ability. Finally, a ferrozine assay showed that curcumin (10-100 µg/mL) has potent Fe(2+)-chelating ability. These results suggest that curcumin and THERACURMIN exert potent protective effects against SNP-induced cytotoxicity by free radical-scavenging and iron-chelating activities.

Copper-Sulfate Pentahydrate as a Product of the Waste Sulfuric Acid Solution Treatment

Science.gov (United States)

Marković, Radmila; Stevanović, Jasmina; Avramović, Ljiljana; Nedeljković, Dragutin; Jugović, Branimir; Stajić-Trošić, Jasna; Gvozdenović, Milica

2012-12-01

The aim of this study is synthesis of copper-sulfate pentahydrate from the waste sulfuric acid solution-mother liquor generated during the regeneration process of copper bleed solution. Copper is removed from the mother liquor solution in the process of the electrolytic treatment using the insoluble lead anodes alloyed with 6 mass pct of antimony on the industrial-scale equipment. As the result of the decopperization process, copper is removed in the form of the cathode sludge and is precipitated at the bottom of the electrolytic cell. By this procedure, the content of copper could be reduced to the 20 mass pct of the initial value. Chemical characterization of the sludge has shown that it contains about 90 mass pct of copper. During the decopperization process, the very strong poison, arsine, can be formed, and the process is in that case terminated. The copper leaching degree of 82 mass pct is obtained using H2SO4 aqueous solution with the oxygen addition during the cathode sludge chemical treatment at 80 °C ± 5 °C. Obtained copper salt satisfies the requirements of the Serbian Standard for Pesticide, SRPS H.P1. 058. Therefore, the treatment of waste sulfuric acid solutions is of great economic and environmental interest.

Emf measurements on nanocrystalline copper-doped ceria

International Nuclear Information System (INIS)

Knauth, P.; Villain, S.

1998-01-01

Mixed oxide samples of nanostructured Cu x Ce 1-x O 2-y of various composition were generated by (i) chemical precipitation and ball milling and (ii) inert gas condensation. X-ray diffraction measurements suggested that copper oxide was dissolved in nanostructured cerium oxide up to concentrations of x = 0.15. Solid electrolyte cells of the type A, Cu 2 O/CuBr/Cu x Ce 1-x O 2-y (A = Cu or CuO) showed reversible cell voltages. The ratio of the formal chemical activities of CuO and Cu 2 O dissolved in nanostructured cerium oxide were calculated from the cell voltages. The results are discussed in terms of an apparent macroscopic solubility, due to interfacial segregation of copper oxide on nanostructured cerium oxide

Susceptibility cancellation of a microcoil wound with a paramagnetic-liquid-filled copper capillary

Science.gov (United States)

Takeda, Kazuyuki; Takasaki, Tomoya; Takegoshi, K.

2015-09-01

Even though microcoils improve the sensitivity of NMR measurement of tiny samples, magnetic-field inhomogeneity due to the bulk susceptibility effect of the coil material can cause serious resonance-line broadening. Here, we propose to fabricate the microcoil using a thin, hollow copper capillary instead of a wire and fill paramagnetic liquid inside the capillary, so as to cancel the diamagnetic contribution of the copper. Susceptibility cancellation is demonstrated using aqueous solution of NiSO4. In addition, the paramagnetic liquid serves as coolant when it is circulated through the copper capillary, effectively transferring the heat generated by radiofrequency pulses.

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

Science.gov (United States)

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

2006-11-02

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

Bioleaching of a low-grade nickel-copper sulfide by mixture of four thermophiles.

Science.gov (United States)

Li, Shuzhen; Zhong, Hui; Hu, Yuehua; Zhao, Jiancun; He, Zhiguo; Gu, Guohua

2014-02-01

This study investigated thermophilic bioleaching of a low grade nickel-copper sulfide using mixture of four acidophilic thermophiles. Effects of 0.2g/L l-cysteine on the bioleaching process were further evaluated. It aimed at offering new alternatives for enhancing metal recoveries from nickel-copper sulfide. Results showed a recovery of 80.4% nickel and 68.2% copper in 16-day bioleaching without l-cysteine; while 83.7% nickel and 81.4% copper were recovered in the presence of l-cysteine. Moreover, nickel recovery was always higher than copper recovery. l-Cysteine was found contributing to lower pH value, faster microbial growth, higher Oxidation-Reduction Potential (ORP), higher zeta potential and absorbing on the sulfide surfaces through amino, carboxyl and sulfhydryl groups. X-ray Diffraction (XRD) patterns of leached residues showed generation of S, jarosite and ammoniojarosite. Denaturing Gradient Gel Electrophoresis (DGGE) results revealed that l-cysteine could have variant impacts on different microorganisms and changed the microbial community composition dramatically during nickel-copper sulfide bioleaching. Copyright © 2013 Elsevier Ltd. All rights reserved.

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.

Influence of feedstock on the copper removal capacity of waste-derived biochars.

Science.gov (United States)

Arán, Diego; Antelo, Juan; Fiol, Sarah; Macías, Felipe

2016-07-01

Biochar samples were generated by low temperature pyrolysis of different types of waste. The physicochemical characteristics of the different types of biochar affected the copper retention capacity, by determining the main mechanism involved. The capacity of the biochar to retain copper present in solution depended on the size of the inorganic fraction and varied in the following order: rice biochar>chicken manure biochar>olive mill waste biochar>acacia biochar>eucalyptus biochar>corn cob biochar. The distribution of copper between the forms bound to solid biochar, dissolved organic matter and free organic matter in solution also depended on the starting material. However, the effect of pH on the adsorption capacity was independent of the nature of the starting material, and the copper retention of all types of biochar increased with pH. Copyright © 2016 Elsevier Ltd. All rights reserved.

Host and Pathogen Copper-Transporting P-Type ATPases Function Antagonistically during Salmonella Infection.

Science.gov (United States)

Ladomersky, Erik; Khan, Aslam; Shanbhag, Vinit; Cavet, Jennifer S; Chan, Jefferson; Weisman, Gary A; Petris, Michael J

2017-09-01

Copper is an essential yet potentially toxic trace element that is required by all aerobic organisms. A key regulator of copper homeostasis in mammalian cells is the copper-transporting P-type ATPase ATP7A, which mediates copper transport from the cytoplasm into the secretory pathway, as well as copper export across the plasma membrane. Previous studies have shown that ATP7A-dependent copper transport is required for killing phagocytosed Escherichia coli in a cultured macrophage cell line. In this investigation, we expanded on these studies by generating Atp7a LysMcre mice, in which the Atp7a gene was specifically deleted in cells of the myeloid lineage, including macrophages. Primary macrophages isolated from Atp7a LysMcre mice exhibit decreased copper transport into phagosomal compartments and a reduced ability to kill Salmonella enterica serovar Typhimurium compared to that of macrophages isolated from wild-type mice. The Atp7a LysMcre mice were also more susceptible to systemic infection by S Typhimurium than wild-type mice. Deletion of the S Typhimurium copper exporters, CopA and GolT, was found to decrease infection in wild-type mice but not in the Atp7a LysMcre mice. These studies suggest that ATP7A-dependent copper transport into the phagosome mediates host defense against S Typhimurium, which is counteracted by copper export from the bacteria via CopA and GolT. These findings reveal unique and opposing functions for copper transporters of the host and pathogen during infection. Copyright © 2017 American Society for Microbiology.

Copper hypersensitivity

DEFF Research Database (Denmark)

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

2014-01-01

hypersensitivity, a database search of PubMed was performed with the following terms: copper, dermatitis, allergic contact dermatitis, contact hypersensitivity, contact sensitization, contact allergy, patch test, dental, IUD, epidemiology, clinical, and experimental. Human exposure to copper is relatively common...

Superhydrophobic Copper Surfaces with Anticorrosion Properties Fabricated by Solventless CVD Methods.

Science.gov (United States)

Vilaró, Ignasi; Yagüe, Jose L; Borrós, Salvador

2017-01-11

Due to continuous miniaturization and increasing number of electrical components in electronics, copper interconnections have become critical for the design of 3D integrated circuits. However, corrosion attack on the copper metal can affect the electronic performance of the material. Superhydrophobic coatings are a commonly used strategy to prevent this undesired effect. In this work, a solventless two-steps process was developed to fabricate superhydrophobic copper surfaces using chemical vapor deposition (CVD) methods. The superhydrophobic state was achieved through the design of a hierarchical structure, combining micro-/nanoscale domains. In the first step, O 2 - and Ar-plasma etchings were performed on the copper substrate to generate microroughness. Afterward, a conformal copolymer, 1H,1H,2H,2H-perfluorodecyl acrylate-ethylene glycol diacrylate [p(PFDA-co-EGDA)], was deposited on top of the metal via initiated CVD (iCVD) to lower the surface energy of the surface. The copolymer topography exhibited a very characteristic and unique nanoworm-like structure. The combination of the nanofeatures of the polymer with the microroughness of the copper led to achievement of the superhydrophobic state. AFM, SEM, and XPS were used to characterize the evolution in topography and chemical composition during the CVD processes. The modified copper showed water contact angles as high as 163° and hysteresis as low as 1°. The coating withstood exposure to aggressive media for extended periods of time. Tafel analysis was used to compare the corrosion rates between bare and modified copper. Results indicated that iCVD-coated copper corrodes 3 orders of magnitude slower than untreated copper. The surface modification process yielded repeatable and robust superhydrophobic coatings with remarkable anticorrosion properties.

Effect of proquinazid and copper hydroxide on homeostasis of anions in winter wheat plants in generative phase of development

Directory of Open Access Journals (Sweden)

M. E. Riazanova

2015-03-01

Full Text Available The study deals with the effect of proquinazid and copper oxide application on structural characteristics and resistance of wheat to powdery mildew, as well as remobilisation and redistribution of anions pools at generative stage of development. The trial series was conducted in the experimental agricultural production of the Institute of Plant Physiology and Genetics, National Academy of Sciences of Ukraine. Field experiments were carried out with Smuglyanka variety of winter wheat. The trial series included the application of fungicides such as Talius (proquinazid, 200 g/L 0,25 L/ha and Kocide 2000 (copper hydroxide, 350 g/kg 150 and 300 g/ha, and combination of both fungicides. Sprays were applied at tillering stage in autumn in the first trial series and at tillering-booting stage in spring in the second one. Assessment of affected plants by powdery mildew was carried out visually in points. Anion concentration was determined with the use of ion chromatography. Application of fungicides at tillering stage increases the amount of productive stems in wheat plants. The highest effect was recorded for application of copper hydroxide at dose of 300 g/ha in autumn. Analysis of plants affected by powdery mildew shows that application of proquinazid and its composition with copper hydroxide provides sustained protection against Blumeria graminis (DC Speer. Application of fungicides at tillering stage contributes to increase of the pool of free nitrogen, phosphorus and sulfur anions in leaf tissues compared to control. These changes in anion composition may be caused by fungicide effect on activity of N, P, S transporters, as well as internal regulatory mechanisms of elements’ uptake by plants. Comparing the results of the autumn and spring application of fungicides should note the increase in concentration of free phosphates in wheat leaves in the 2nd trial with proquinazid and its composition with copper hydroxide. Accumulation of nitrogen in the

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

Science.gov (United States)

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

2018-01-24

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

Fabricating Copper Nanotubes by Electrodeposition

Science.gov (United States)

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

2009-01-01

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

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

International Nuclear Information System (INIS)

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

2017-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2017-02-28

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

Surface characteristics, copper release, and toxicity of nano- and micrometer-sized copper and copper(II) oxide particles: a cross-disciplinary study.

OpenAIRE

Midander, Klara; Cronholm, Pontus; Karlsson, Hanna L.; Elihn, Karine; Moller, Lennart; Leygraf, Christofer; Wallinder, Inger Odnevall

2009-01-01

An interdisciplinary and multianalytical research effort is undertaken to assess the toxic aspects of thoroughly characterized nano- and micrometer-sized particles of oxidized metallic copper and copper(II) oxide in contact with cultivated lung cells, as well as copper release in relevant media. All particles, except micrometer-sized Cu, release more copper in serum-containing cell medium (supplemented Dulbecco's minimal essential medium) compared to identical exposures in phosphate-buffered ...

Copper-promoted cementation of antimony in hydrochloric acid system: A green protocol

Energy Technology Data Exchange (ETDEWEB)

Wu, Lian-Kui; Li, Ying-Ying; Cao, Hua-Zhen; Zheng, Guo-Qu, E-mail: zhenggq@zjut.edu.cn

2015-12-15

Highlights: • Antimony can be efficiently removed by cementation with copper powder. • Cemented antimony is in the form of Cu{sub 2}Sb. • Consumed copper powder is transformed to CuCl. • The cementation is a chemically controlled step. • No toxic stibine generates during the cementation process. - Abstract: A new method of recovering antimony in hydrochloric acid system by cementation with copper powder was proposed and carried out at laboratory scale. Thermodynamic analysis and cyclic voltammetry test were conducted to study the cementation process. This is a novel antimony removal technology and quite meets the requirements of green chemistry. The main cement product Cu{sub 2}Sb is a promising anodic material for lithium and sodium ion battery. And nearly all consumed copper powder are transformed into CuCl which is an important industrial material. The effect of reaction temperature, stoichiometric ratio of Cu to Sb(III), stirring rate and concentration of HCl on the cementation efficiency of antimony were investigated in detail. Optimized cementation condition is obtained at 60 °C for 120 min and stirring rate of 600 rpm with Cu/Sb(III) stoichiometric ratio of 6 in 3 mol L{sup −1} HCl. At this time, nearly all antimony can be removed by copper powder and the cementation efficiency is over 99%. The structure and morphologies of the cement products were characterized by X-ray diffraction and scanning electron microscopy, respectively. Results show that the reaction temperature has little influence on the morphology of the cement products which consist of particles with various sizes. The activation energy of the cementation antimony on copper is 37.75 kJ mol{sup −1}, indicating a chemically controlled step. Inductively coupled plasma mass spectrometry results show that no stibine generates during the cementation process.

Nafion/lead nitroprusside nanoparticles modified carbon ceramic electrode as a novel amperometric sensor for L-cysteine.

Science.gov (United States)

Razmi, H; Heidari, H

2009-05-01

This work describes the electrochemical and electrocatalytic properties of carbon ceramic electrode (CCE) modified with lead nitroprusside (PbNP) nanoparticles as a new electrocatalyst material. The structure of deposited film on the CCE was characterized by energy dispersive X-ray (EDX), Fourier transform infrared (FTIR), and scanning electron microscopy (SEM). The cyclic voltammogram (CV) of the PbNP modified CCE showed two well-defined redox couples due to [Fe(CN)5NO](3-)/[Fe(CN)5NO](2-) and Pb(IV)/Pb(II) redox reactions. The modified electrode showed electrocatalytic activity toward the oxidation of L-cysteine and was used as an amperometric sensor. Also, to reduce the fouling effect of L-cysteine and its oxidation products on the modified electrode, a thin film of Nafion was coated on the electrode surface. The sensor response was linearly changed with L-cysteine concentration in the range of 1 x 10(-6) to 6.72 x 10(-5)mol L(-1) with a detection limit (signal/noise ratio [S/N]=3) of 0.46 microM. The sensor sensitivity was 0.17 microA (microM)(-1), and some important advantages such as simple preparation, fast response, good stability, interference-free signals, antifouling properties, and reproducibility of the sensor for amperometric determination of L-cysteine were achieved.

Copper thin film for RFID UHF antenna on flexible substrate

International Nuclear Information System (INIS)

Tran, Nhan Ai; Tran, Huy Nam; Dang, Mau Chien; Fribourg-Blanc, Eric

2010-01-01

A process flow using photolithography and sputtering was studied for copper antenna fabrication on thin poly(ethylene terephthalate) (PET) substrate. The lift-off route was chosen for its flexibility at laboratory scale. It was clarified that the cleaning of PET is an important step that necessitates mild oxygen plasma etching. Then copper is sputter deposited after photolithographic definition of the antenna. Care is necessary since PET, as a very flexible substrate, is temperature sensitive. The temperature increase generated by the impact of deposited copper should be maintained below the glass transition temperature of the polymer to avoid detrimental deformation. dc power of 40 to 50 W was found to be the maximum possible sputtering power for commercial PET. It was found that the resistivity of the thin film is below two times the bulk resistivity of copper for a deposition pressure below 4×10 −3  mbar and thickness above 450 nm. These results enable the reliable fabrication of copper RFID UHF antennae on a PET substrate for further testing of new tag designs. The present paper summarizes the effort to test new designs of antennae for RadioFrequency IDentification (RFID) Ultra High Frequency (UHF) tags, for use in various applications (e.g. object tracking and environment monitoring) in Vietnam

Copper metabolism: a multicompartmental model of copper kinetics in the rat

International Nuclear Information System (INIS)

Dunn, M.A.

1985-01-01

A qualitative multicompartmental model was developed that describes the whole-body kinetics of copper metabolism in the adult rat. The model was developed from radiocopper percent dose vs. time data measured over a three day period in plasma, liver, skin, skeletal muscle, bile and feces after the intravenous injection of 10 μg copper labeled with 64 Cu. Plasma radiocopper was separated into ceruloplasmin (Cp) and nonceruloplasmin (NCp) fractions. Liver cytosolic radiocopper was fractionated into void volume superoxide dismutase (SOD) containing and metallothionein fractions by gel filtration. Liver particulate fractions were isolated by differential centrifugation. The SAAM and CONSAM modeling programs were used to develop the model. The sizes of compartments, fractional rate constants and mass transfer rates between compartments were evaluated. The intracellular metabolism of copper was similar in hepatic and extrahepatic tissues being comprised of a faster turning over compartment (FTC) exchanging copper with NCp and a slower turning over compartment (STC) with input from Cp. Output from the STC was into the FTC. In the liver the STC was postulated to represent SOD copper which unlike the extrahepatic tissues received much of its input from the FTC. A small amount of biliary copper (9%) was postulated to return to plasma NCp by enterohepatic recycling. The model developed was contrasted and compared with two previous models of copper metabolism

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.

ROS dependent copper toxicity in Hydra-biochemical and molecular study.

Science.gov (United States)

Zeeshan, Mohammed; Murugadas, Anbazhagan; Ghaskadbi, Surendra; Rajendran, Ramasamy Babu; Akbarsha, Mohammad Abdulkader

2016-01-01

Copper, an essential microelement, is known to be toxic to aquatic life at concentrations higher than that could be tolerated. Copper-induced oxidative stress has been documented in vitro, yet the in vivo effects of metal-induced oxidative stress have not been extensively studied in the lower invertebrates. The objective of the present study has been to find the effect of ROS-mediated toxicity of environmentally relevant concentrations of copper at organismal and cellular levels in Hydra magnipapillata. Exposure to copper at sublethal concentrations (0.06 and 0.1mg/L) for 24 or 48h resulted in generation of significant levels of intracellular reactive oxygen species (ROS). We infer that the free radicals here originate predominantly at the lysosomes but partly at the mitochondria also as visualized by H2-DHCFDA staining. Quantitative real-time PCR of RNA extracted from copper-exposed polyps revealed dose-dependent up-regulation of all antioxidant response genes (CAT, SOD, GPx, GST, GR, G6PD). Concurrent increase of Hsp70 and FoxO genes suggests the ability of polyps to respond to stress, which at 48h was not the same as at 24h. Interestingly, the transcript levels of all genes were down-regulated at 48h as compared to 24h incubation period. Comet assay indicated copper as a powerful genotoxicant, and the DNA damage was dose- as well as duration-dependent. Western blotting of proteins (Bax, Bcl-2 and caspase-3) confirmed ROS-mediated mitochondrial cell death in copper-exposed animals. These changes correlated well with changes in morphology, regeneration and aspects of reproduction. Taken together, the results indicate increased production of intracellular ROS in Hydra on copper exposure. Copyright © 2016 Elsevier Inc. All rights reserved.

Investigation of the susceptibility to solidification cracking in copper alloys

Energy Technology Data Exchange (ETDEWEB)

Warren, Richard [Avesta Sheffield R and D, Avesta (Sweden)

2000-04-01

A test procedure has been developed at LuTH for investigating the susceptibility to cracking at high temperatures in weldments. It has been proposed to adapt this testing procedure to investigate the cracking susceptibility at high temperatures during strip casting of certain copper alloys. Six different materials were selected for investigation - OFHC copper, tellurium containing copper, 4% tin bronze, 6% tin bronze, 30% zinc brass and 35% zinc brass. The aim of the investigation was to characterize the cracking susceptibility of the candidate materials so as to be able to rank and compare them in a quantitative manner. A further aim of the work was to study the suitability of using the data on the cracking indices generated in the present work in thermomechanical models of the casting process to optimize the casting parameters for each of the materials.

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.

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.

Microstructure and interfacial evaluation of Co-based alloy coating on copper by pulsed Nd:YAG multilayer laser cladding

International Nuclear Information System (INIS)

Yan Hua; Wang Aihua; Xu Kaidong; Wang Wenyan; Huang Zaowen

2010-01-01

Laser cladding defect-free coatings on copper is rather difficult. The purpose of this study is to fabricate high quality Co-based alloy coating on copper substrate by laser cladding. Powder preplacement with a thickness of 0.7 mm improves the absorptivity of copper substrate to laser effectively and generates defect-free coating. Microstructures, phase constitutions and wear properties are investigated by means of scanning electronic microscopy (SEM) with X-ray energy dispersive microanalysis (EDX), transmission electron microscopy (TEM) and X-ray diffraction (XRD), as well as dry sliding wear test. Experimental results show that α-Co solution, Cr 23 C 6 , Ni 17 W 3 and Cr 4 Ni 15 W are the main phases in the Co-based coating. The Ni-based solid solutions (α-Co, Ni) and (Ni, Cu) are formed at interface, which generate metallurgical bonding by diffusion between Co-based coating and copper substrate. The average microhardness of the coating is 478HV 0.1 . Wear resistance of copper is significantly improved by laser cladding Co-based alloy multilayer coating.

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

Indian Academy of Sciences (India)

Administrator

aCentre for Materials Research, Department of Imaging and Applied Physics, ... Copper powder; Si/Cu composite particle; gas evaporation–condensation method; characteriza- tion. .... from the liquid metal surface, the mixed vapour of copper.

Cerebral blood flow and metabolism during controlled hypotension with sodium-nitroprusside and general anaesthesia for total hip replacement a.m. Charnley

International Nuclear Information System (INIS)

Buenemann, L.; Jensen, K.; Thomsen, L.; Riisager, S.

1987-01-01

Cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRo 2 ) were studied during hypotension induced with sodium nitroprusside (SNP) in 10 patients undergoing total hip replacement a.m. Charnley. Cerebral blood flow was measured using an injection of xenon-133 into an arm vein. The decay curve was detected by five scintillation counters placed over each hemisphere and analysed with the Novo 10a cerebrograph. Blood samples were drawn from the radial artery and the jugular venous bulb to calculate the CMRo 2 . In the gropu as a whole, there were significant decreases in mean arterial pressure and in cerebrovascular resistance. There were no significant changes, in either CBF or CMRo 2 in the gropu as a whole, but there were substantial individual differences. In conclusion, the use of SNP-induced hypotension for extracranial surgery should be used only in patients monitored closely. (author)

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.

Mobilization of Intracellular Copper by Gossypol and Apogossypolone Leads to Reactive Oxygen Species-Mediated Cell Death: Putative Anticancer Mechanism

Directory of Open Access Journals (Sweden)

Haseeb Zubair

2016-06-01

Full Text Available There is compelling evidence that serum, tissue and intracellular levels of copper are elevated in all types of cancer. Copper has been suggested as an important co-factor for angiogenesis. It is also a major metal ion present inside the nucleus, bound to DNA bases, particularly guanine. We have earlier proposed that the interaction of phenolic-antioxidants with intracellular copper leads to the generation of reactive oxygen species (ROS that ultimately serve as DNA cleaving agents. To further validate our hypothesis we show here that the antioxidant gossypol and its semi-synthetic derivative apogossypolone induce copper-mediated apoptosis in breast MDA-MB-231, prostate PC3 and pancreatic BxPC-3 cancer cells, through the generation of ROS. MCF10A breast epithelial cells refractory to the cytotoxic property of these compounds become sensitized to treatment against gossypol, as well as apogossypolone, when pre-incubated with copper. Our present results confirm our earlier findings and strengthen our hypothesis that plant-derived antioxidants mobilize intracellular copper instigating ROS-mediated cellular DNA breakage. As cancer cells exist under significant oxidative stress, this increase in ROS-stress to cytotoxic levels could be a successful anticancer approach.

Demystifying Controlling Copper Corrosion

Science.gov (United States)

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

Copper Bioleaching in Chile

OpenAIRE

Juan Carlos Gentina; Fernando Acevedo

2016-01-01

Chile has a great tradition of producing and exporting copper. Over the last several decades, it has become the first producer on an international level. Its copper reserves are also the most important on the planet. However, after years of mineral exploitation, the ease of extracting copper oxides and ore copper content has diminished. To keep the production level high, the introduction of new technologies has become necessary. One that has been successful is bioleaching. Chile had the first...

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...

Synthesis and characterization of a new composite based on copper (II) and octa (aminopropil)silsesquioxane; Sintese e caracterizacao de novos compositos a base de cobre (II) e octa(aminopropil)silsesquioxano

Energy Technology Data Exchange (ETDEWEB)

Magossi, M.S. de; Carmo, D.R. do, E-mail: marymagossi@gmail.com [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Ilha Solteira, SP (Brazil). Faculdade de Engenharia

2014-07-01

In this work, a new compound based silsesquioxane and nitroprusside of copper was prepared starting from octa (aminopropyl)silsesquioxane following a new route of synthesis. The composite prepared as described ACCuN was preliminarily characterized by spectroscopic techniques, such as Infrared Spectroscopy in the Region of the Fourier transform (FTIR), Energy Dispersive X-ray (EDX), Scanning Electron Microscopy (SEM) and cyclic voltammetry (VC). The FTIR spectra showed absorption bands at 1106 cm{sup -1} due to stretching Si-O-Si{sub (νSi-O-Si)} characteristic of the structure of octa(aminopropylsilsesquioxane and absorption bands at 2063 cm{sup -1} ascribed to the stretching NO{sub (νN-O}) and 2192 cm{sup -1} attributed to the stretching C≡N{sub (ν≡}N{sub )}. SEM and EDX observed cluster of cubic particles with an average size of approximately 241 nm, containing Si, O, N, Cu and Fe. Cyclic voltammogram of the material (ACCuN) showed a redox couple with average potential Eθ '= 0.73 V. (author)

Recovery of Copper from Copper Slag by Hydrometallurgy Method, from Iraqi Factories Waste

Directory of Open Access Journals (Sweden)

Bahaa Sami Mahdi

2018-05-01

Full Text Available   In this research, the recovery of copper from copper slag is investigated using hydrometallurgy method. Slag samples were taken from Al-Shaheed State Company. The results of the chemical analysis showed that the slag contained 11.4% of copper. The recovery process included two stages; the first stage is leaching using diluted sulfuric acid. The most important variables that effect on the leaching process was studied, such as acid concentration, hydrogen peroxide adding, particle size, liquid to solid, stirring speed and leaching time by changing the condition and the stabilizing of other factors at room temperature.               The second stage is precipitation of copper from leaching solution by zinc powder with different weights and times, at room temperature and 1.5 PH value. The results of the first stage manifested that about 99.7% of the copper have been dissolved at the following operational conditions: 50% acid concentration, 5 ml hydrogen peroxide adding, particle size (-75+53 micron, 1:10 liquid to solid, 500 rpm stirring speed and 25 min of leaching time. The highest percentage of copper precipitation in the second stage was 99.8% when added 3gm zinc powder at 20 min. The XRD result revealed that the predominant phase was pure copper. The results of EDS exhibited that a few percentage of oxygen appeared with copper powder. The final of copper recovery ratio was 99.3% with 99.2% purity.

Bacterial Killing by Dry Metallic Copper Surfaces▿

OpenAIRE

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

2010-01-01

Metallic copper surfaces rapidly and efficiently kill bacteria. Cells exposed to copper surfaces accumulated large amounts of copper ions, and this copper uptake was faster from dry copper than from moist copper. Cells suffered extensive membrane damage within minutes of exposure to dry copper. Further, cells removed from copper showed loss of cell integrity. Acute contact with metallic copper surfaces did not result in increased mutation rates or DNA lesions. These findings are important fir...

A novel copper complex induces ROS generation in doxorubicin resistant Ehrlich ascitis carcinoma cells and increases activity of antioxidant enzymes in vital organs in vivo

International Nuclear Information System (INIS)

Mookerjee, Ananda; Roy, Syamal; Choudhuri, Soumitra K; Basu, Jayati Mookerjee; Majumder, Surajit; Chatterjee, Shilpak; Panda, Gouri S; Dutta, Pranabananda; Pal, Smarajit; Mukherjee, Pratima; Efferth, Thomas

2006-01-01

In search of a suitable GSH-depleting agent, a novel copper complex viz., copper N-(2-hydroxyacetophenone) glycinate (CuNG) has been synthesized, which was initially found to be a potential resistance modifying agent and later found to be an immunomodulator in mice model in different doses. The objective of the present work was to decipher the effect of CuNG on reactive oxygen species (ROS) generation and antioxidant enzymes in normal and doxorubicin-resistant Ehrlich ascites carcinoma (EAC/Dox)-bearing Swiss albino mice. The effect of CuNG has been studied on ROS generation, multidrug resistance-associated protein1 (MRP1) expression and on activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). CuNG increased ROS generation and reduced MRP1 expression in EAC/Dox cells while only temporarily depleted glutathione (GSH) within 2 h in heart, kidney, liver and lung of EAC/Dox bearing mice, which were restored within 24 h. The level of liver Cu was observed to be inversely proportional to the level of GSH. Moreover, CuNG modulated SOD, CAT and GPx in different organs and thereby reduced oxidative stress. Thus nontoxic dose of CuNG may be utilized to reduce MRP1 expression and thus sensitize EAC/Dox cells to standard chemotherapy. Moreover, CuNG modulated SOD, CAT and and GPx activities to reduce oxidative stress in some vital organs of EAC/Dox bearing mice. CuNG treatment also helped to recover liver and renal function in EAC/Dox bearing mice. Based on our studies, we conclude that CuNG may be a promising candidate to sensitize drug resistant cancers in the clinic

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

Science.gov (United States)

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

2012-04-01

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

Current trends in copper theft prevention

Energy Technology Data Exchange (ETDEWEB)

Mastrofrancesco, A. [Electrical Safety Authority, ON (Canada)

2009-07-01

Copper is used in electrical wiring, water and gas piping, currency, and in household items. An increase in the price and demand for copper has made copper theft a profitable venture for some thieves. Copper consumed in North America is typically supplied by recycling. Scrap dealers may pay near-market prices for pure copper wires. However, copper theft poses a serious threat to the safety of utility workers and the public. Power outages caused by copper theft are now affecting grid reliability. This paper examined technologies and techniques used to prevent copper theft as part of a security strategy for utilities. Attempts to steal copper can leave utility substations unsecured and accessible to children. The theft of neutral grounds will cause the local distribution company (LDC) to malfunction and may cause power surges in homes as well as appliance fires. Utilities are now looking at using a hybrid steel and copper alternative to prevent copper theft. Asset identification techniques are also being used to identify the original owners of the copper and more easily prosecute thieves. Automated monitoring techniques are also being used to increase substation security. Utilities are also partnering with law enforcement agencies and pressuring governments to require scrap dealers to record who they buy from. It was concluded that strategies to prevent copper theft should be considered as part of an overall security strategy for utilities. tabs., figs.

Copper Recovery from Yulong Complex Copper Oxide Ore by Flotation and Magnetic Separation

Science.gov (United States)

Han, Junwei; Xiao, Jun; Qin, Wenqing; Chen, Daixiong; Liu, Wei

2017-09-01

A combined process of flotation and high-gradient magnetic separation was proposed to utilize Yulong complex copper oxide ore. The effects of particle size, activators, Na2S dosage, LA (a mixture of ammonium sulfate and ethylenediamine) dosage, activating time, collectors, COC (a combination collector of modified hydroxyl oxime acid and xanthate) dosage, and magnetic intensity on the copper recovery were investigated. The results showed that 74.08% Cu was recovered by flotation, while the average grade of the copper concentrates was 21.68%. Another 17.34% Cu was further recovered from the flotation tailing by magnetic separation at 0.8 T. The cumulative recovery of copper reached 91.42%. The modifier LA played a positive role in facilitating the sulfidation of copper oxide with Na2S, and the combined collector COC was better than other collectors for the copper flotation. This technology has been successfully applied to industrial production, and the results are consistent with the laboratory data.

Preparation of graphite dispersed copper composite on copper plate with CO2 laser

Science.gov (United States)

Yokoyama, S.; Ishikawa, Y.; Muizz, M. N. A.; Hisyamudin, M. N. N.; Nishiyama, K.; Sasano, J.; Izaki, M.

2018-01-01

It was tried in this work to prepare the graphite dispersed copper composite locally on a copper plate with a CO2 laser. The objectives of this study were to clear whether copper graphite composite was prepared on a copper plate and how the composite was prepared. The carbon content at the laser spot decreased with the laser irradiation time. This mainly resulted from the elimination by the laser trapping. The carbon content at the outside of the laser spot increased with time. Both the laser ablation and the laser trapping did not act on the graphite particles at the outside of the laser spot. Because the copper at the outside of the laser spot melted by the heat conduction from the laser spot, the particles were fixed by the wetting. However, the graphite particles were half-floated on the copper plate. The Vickers hardness decreased with an increase with laser irradiation time because of annealing.

Assessment of the anti-biofouling potentials of a copper iodide-doped nylon mesh.

Science.gov (United States)

Sato, Tetsuya; Fujimori, Yoshie; Nakayama, Tsuruo; Gotoh, Yasuo; Sunaga, Yoshihiko; Nemoto, Michiko; Matsunaga, Tadashi; Tanaka, Tsuyoshi

2012-08-01

We propose a copper iodide (CuI)-doped nylon mesh prepared using polyiodide ions as a precursor toward anti-biofouling polymer textile. The CuI-doped nylon mesh was subjected to the prevention of biofouling in marine environments. The attachment of the marine organisms was markedly inhibited on the CuI-doped nylon mesh surface until 249 days. Scanning electron microscopy-energy dispersive X-ray analysis indicated that copper compounds were maintained in the nylon mesh after the field experiment, although copper content in the nylon mesh was reduced. Therefore, the copper ions slowly dissolved from nylon mesh will contribute to the long-term prevention of biofouling. Furthermore, electron spin resonance analysis revealed the generation of reactive oxygen species (ROS) from CuI-doped nylon mesh after the field experiment. One of the possibilities for toxic action of copper ions will be the direct effect of Cu+ -induced ROS on biofilm forming on nylon mesh surface. The proposed polymer textile can be applied to fishing and aquafarming nets, mooring rope for ship, or silt fence to restrict polluted water in marine environments.

Copper-carbon and aluminum-carbon composites fabricated by powder metallurgy processes

International Nuclear Information System (INIS)

Silvain, Jean-François; Veillère, Amélie; Lu, Yongfeng

2014-01-01

The increase in both power and packing densities in power electronic devices has led to an increase in the market demand for effective heat-dissipating materials, with high thermal conductivity and thermal- expansion coefficient compatible with chip materials still ensuring the reliability of the power modules. In this context, metal matrix composites: carbon fibers and diamond-reinforced copper and aluminum matrix composites among them are considered very promising as a next generation of thermal-management materials in power electronic packages. These composites exhibit enhanced thermal properties compared to pure copper combined with lower density. This article presents the fabrication techniques of copper/carbon fibers and copper/diamond and aluminum/carbon fibers composite films by powder metallurgy and hot pressing. The thermal analyses clearly indicate that interfacial treatments are required in these composites to achieve high thermomechanical properties. Interfaces (through novel chemical and processing methods), when selected carefully and processed properly will form the right chemical/mechanical link between metal and carbon, enhancing all the desired thermal properties while minimizing the deleterious effect.

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

Science.gov (United States)

DeAlba-Montero, I.; Morales-Sánchez, Elpidio; Araujo-Martínez, Rene

2017-01-01

This paper reports a comparison of the antibacterial properties of copper-amino acids chelates and copper nanoparticles against Escherichia coli, Staphylococcus aureus, and Enterococcus faecalis. These copper-amino acids chelates were synthesized by using a soybean aqueous extract and copper nanoparticles were produced using as a starting material the copper-amino acids chelates species. The antibacterial activity of the samples was evaluated by using the standard microdilution method (CLSI M100-S25 January 2015). In the antibacterial activity assays copper ions and copper-EDTA chelates were included as references, so that copper-amino acids chelates can be particularly suitable for acting as an antibacterial agent, so they are excellent candidates for specific applications. Additionally, to confirm the antimicrobial mechanism on bacterial cells, MTT assay (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) was carried out. A significant enhanced antimicrobial activity and a specific strain were found for copper chelates over E. faecalis. Its results would eventually lead to better utilization of copper-amino acids chelate for specific application where copper nanoparticles can be not used. PMID:28286459

An econometric model of the U.S. secondary copper industry: Recycling versus disposal

Science.gov (United States)

Slade, M.E.

1980-01-01

In this paper, a theoretical model of secondary recovery is developed that integrates microeconomic theories of production and cost with a dynamic model of scrap generation and accumulation. The model equations are estimated for the U.S. secondary copper industry and used to assess the impacts that various policies and future events have on copper recycling rates. The alternatives considered are: subsidies for secondary production, differing energy costs, and varying ore quality in primary production. ?? 1990.

Leaching of copper concentrates using NaCl and soluble copper contributed by the own concentrate; Lixiviacion de concentrados de cobre utilizando NaCl y el cobre soluble aportado por el propio concentrado

Energy Technology Data Exchange (ETDEWEB)

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

2005-07-01

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.

Chromatic annuli formation and sample oxidation on copper thin films by femtosecond laser

Energy Technology Data Exchange (ETDEWEB)

He, Shutong [Ultrafast Laser Laboratory, Key Laboratory of Opto-Electronic Information Technical Science of Ministry of Education, College of Precision Instruments and Opto-Electronics Engineering, Tianjin University, Tianjin 300072 (China); Dipartimento di Fisica, Università di Napoli Federico II, Complesso Universitario di Monte S. Angelo, Via Cintia, I-80126 Napoli (Italy); Amoruso, Salvatore [Dipartimento di Fisica, Università di Napoli Federico II, Complesso Universitario di Monte S. Angelo, Via Cintia, I-80126 Napoli (Italy); Pang, Dongqing; Wang, Chingyue; Hu, Minglie, E-mail: huminglie@tju.edu.cn [Ultrafast Laser Laboratory, Key Laboratory of Opto-Electronic Information Technical Science of Ministry of Education, College of Precision Instruments and Opto-Electronics Engineering, Tianjin University, Tianjin 300072 (China)

2016-04-28

We report an experimental investigation on the irradiation of copper thin films with high repetition rate femtosecond laser pulses (1040 nm, 50 MHz), in ambient air and liquid water. We observe a novel, striking phenomenon of chromatic copper oxides (CuO and Cu{sub 2}O) annuli generation. The characteristic features of the chromatic copper oxide annuli are studied by exploiting micro-Raman spectroscopy, optical and scanning electron microscopies. In the case of irradiation in water, the seldom investigated effects of the immersion time, t{sub w}, after irradiation with a fixed number of pulses are analyzed, and an intriguing dependence of the color of the chromatic annuli on t{sub w} is observed. This remarkable behavior is explained by proposing an interpretation scenario addressing the various processes involved in the process. Our experimental findings show that Cu{sub 2}O nanoparticles (size of ≈20 nm) and Cu{sub 2}O nanocubes (nanocube edges of ≈30, ≈60 nm) can be effectively generated by exploiting high repetition rate laser-assisted oxidation.

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

International Nuclear Information System (INIS)

Marcos, N.

1996-10-01

The Hyrkkoelae U-Cu mineralization is located in southwestern Finland, near the Palmottu analogue site. The age of the mineralization is estimated to be between 1.8 and 1.7 Ga. Petrological and mineralogical studies have demonstrated that this mineralization has many geological features that parallel those of the sites being considered for nuclear waste disposal in Finland. A particular feature is the existence of native copper and copper sulfides in open fractures in the near-surface zone. This allows us to study the native copper corrosion process in analogous conditions as expected to dominate in the nuclear fuel waste repository. The occurrence of uranyl compounds at these fractures permits also considerations about the sorption properties of the engineered barrier material (metallic copper) and its corrosion products. From the study of mineral assemblages or paragenesis, it appears that the formation of copper sulfide (djurleite, Cu 1.934 ) after native copper (Cu 0 ) under anoxic (reducing) conditions is enhanced by the availability of dissolved HS - in the groundwater circulating in open fractures in the near-surface zone. The minimum concentration of HS - in the groundwater is estimated to be of the order of 10 -5 M (∼ 10 -4 g/l) and the minimum pH value not lower than about 7.8 as indicated by the presence of calcite crystals in the same fracture. The present study is the first one that has been performed on findings of native copper in reducing, neutral to slightly alkaline groundwaters. Thus, the data obtained is of most relevance in improving models of anoxic corrosion of copper canisters. (orig.)

Copper removal from acid mine drainage-polluted water using glutaraldehyde-polyethyleneimine modified diatomaceous earth particles

Directory of Open Access Journals (Sweden)

Mikael Larsson

2018-02-01

Full Text Available Mine waters and tailings generated from mining and mineral processing activities often have detrimental impact on the local environment. One example is acid mine drainage, in which sulphides in the mining waste react with water and oxygen to produce an acidic environment that subsequently dissolves host rock minerals from the waste containing toxic metals and trace elements. Copper is one such metal of significance, as it is mined at large volumes in sulphide containing ores. It has strong biocidal activity that greatly affects ecosystems. We have previously reported that glutaraldehyde (GA-crosslinked polyethyleneimine (PEI has strong affinity and selectivity for copper and that diatomaceous earth (DE particles can be modified with the material to form a copper-extraction resin. In this study, the copper uptake of GA-PEI-DE particles was investigated from synthetic and real acid mine drainage samples under different pHs and their copper removal performance was compared with that of selected commercial resins. The results revealed that copper could effectively and preferentially bind to the material at pH 4, and that the copper could be completely eluted by lowering of the pH. In addition, effective copper uptake and elution was demonstrated using real legacy acid mine drainage water from Mount Lyell in Tasmania.

Unbundling in Current Broadband and Next-Generation Ultra-Broadband Access Networks

Science.gov (United States)

Gaudino, Roberto; Giuliano, Romeo; Mazzenga, Franco; Valcarenghi, Luca; Vatalaro, Francesco

2014-05-01

This article overviews the methods that are currently under investigation for implementing multi-operator open-access/shared-access techniques in next-generation access ultra-broadband architectures, starting from the traditional "unbundling-of-the-local-loop" techniques implemented in legacy twisted-pair digital subscriber line access networks. A straightforward replication of these copper-based unbundling-of-the-local-loop techniques is usually not feasible on next-generation access networks, including fiber-to-the-home point-to-multipoint passive optical networks. To investigate this issue, the article first gives a concise description of traditional copper-based unbundling-of-the-local-loop solutions, then focalizes on both next-generation access hybrid fiber-copper digital subscriber line fiber-to-the-cabinet scenarios and on fiber to the home by accounting for the mix of regulatory and technological reasons driving the next-generation access migration path, focusing mostly on the European situation.

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)

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

DEFF Research Database (Denmark)

Elguindi, J; Moffitt, S; Hasman, Henrik

2010-01-01

of both copper ion-resistant E. coli and E. faecium strains when samples in rich medium were spread in a thin, moist layer on copper alloys with 85% or greater copper content. E. coli strains were rapidly killed under dry conditions, while E. faecium strains were less affected. Electroplated copper...... on electroplated copper surfaces with benzotriazole coating and thermal oxide coating compared to surfaces without anti-corrosion treatment. Control of surface corrosion affected the level of copper ion influx into bacterial cells, which contributed directly to bacterial killing....

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.

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

Crystal structures of copper(II) chloride, copper(II) bromide, and copper(II) nitrate complexes with pyridine-2-carbaldehyde thiosemicarbazone

Science.gov (United States)

Chumakov, Yu. M.; Tsapkov, V. I.; Jeanneau, E.; Bairac, N. N.; Bocelli, G.; Poirier, D.; Roy, J.; Gulea, A. P.

2008-09-01

The crystal structures of chloro-(2-formylpyridinethiosemicarbazono)copper dimethyl sulfoxide solvate ( I), bromo-(2-formylpyridinethiosemicarbazono)copper ( II), and (2-formylpyridinethiosemicarbazono)copper(II) nitrate dimethyl sulfoxide solvate ( III) are determined using X-ray diffraction. In the crystals, complexes I and II form centrosymmetric dimers in which the thiosemicarbazone sulfur atom serves as a bridge and occupies the fifth coordination site of the copper atom of the neighboring complex related to the initial complex through the center of symmetry. In both cases, the coordination polyhedron of the complexing ion is a distorted tetragonal bipyramid. Complex III in the crystal structure forms polymer chains in which the copper atom of one complex forms the coordination bond with the thicarbamide nitrogen atom of the neighboring complex. In this structure, the coordination polyhedron of the central atom is an elongated tetragonal bipyramid. It is established that complexes I III at a concentration of 10-5 mol/l selectively inhibit the growth of 60 to 90 percent of the cancer tumor cells of the human myeloid leukemia (HL-60).

Crystal structures of copper(II) chloride, copper(II) bromide, and copper(II) nitrate complexes with pyridine-2-carbaldehyde thiosemicarbazone

International Nuclear Information System (INIS)

Chumakov, Yu. M.; Tsapkov, V. I.; Jeanneau, E.; Bairac, N. N.; Bocelli, G.; Poirier, D.; Roy, J.; Gulea, A. P.

2008-01-01

The crystal structures of chloro-(2-formylpyridinethiosemicarbazono)copper dimethyl sulfoxide solvate (I), bromo-(2-formylpyridinethiosemicarbazono)copper (II), and (2-formylpyridinethiosemicarbazono)copper(II) nitrate dimethyl sulfoxide solvate (III) are determined using X-ray diffraction. In the crystals, complexes I and II form centrosymmetric dimers in which the thiosemicarbazone sulfur atom serves as a bridge and occupies the fifth coordination site of the copper atom of the neighboring complex related to the initial complex through the center of symmetry. In both cases, the coordination polyhedron of the complexing ion is a distorted tetragonal bipyramid. Complex III in the crystal structure forms polymer chains in which the copper atom of one complex forms the coordination bond with the thicarbamide nitrogen atom of the neighboring complex. In this structure, the coordination polyhedron of the central atom is an elongated tetragonal bipyramid. It is established that complexes I-III at a concentration of 10 -5 mol/l selectively inhibit the growth of 60 to 90 percent of the cancer tumor cells of the human myeloid leukemia (HL-60).

Crystal structures of copper(II) chloride, copper(II) bromide, and copper(II) nitrate complexes with pyridine-2-carbaldehyde thiosemicarbazone

Energy Technology Data Exchange (ETDEWEB)

Chumakov, Yu. M., E-mail: chumakov.xray@phys.asm.md [Academy of Sciences of Moldova, Institute of Applied Physics (Moldova, Republic of); Tsapkov, V. I. [State University of Moldova (Moldova, Republic of); Jeanneau, E. [Universite Claude Bernard, Laboratoire des Multimateriaux et Interfaces (France); Bairac, N. N. [State University of Moldova (Moldova, Republic of); Bocelli, G. [National Research Council (IMEM-CNR), Institute of Materials for Electronics and Magnetism (Italy); Poirier, D.; Roy, J. [Centre Hospitalier Universitaire de Quebec (CHUQ) (Canada); Gulea, A. P. [State University of Moldova (Moldova, Republic of)

2008-09-15

The crystal structures of chloro-(2-formylpyridinethiosemicarbazono)copper dimethyl sulfoxide solvate (I), bromo-(2-formylpyridinethiosemicarbazono)copper (II), and (2-formylpyridinethiosemicarbazono)copper(II) nitrate dimethyl sulfoxide solvate (III) are determined using X-ray diffraction. In the crystals, complexes I and II form centrosymmetric dimers in which the thiosemicarbazone sulfur atom serves as a bridge and occupies the fifth coordination site of the copper atom of the neighboring complex related to the initial complex through the center of symmetry. In both cases, the coordination polyhedron of the complexing ion is a distorted tetragonal bipyramid. Complex III in the crystal structure forms polymer chains in which the copper atom of one complex forms the coordination bond with the thicarbamide nitrogen atom of the neighboring complex. In this structure, the coordination polyhedron of the central atom is an elongated tetragonal bipyramid. It is established that complexes I-III at a concentration of 10{sup -5} mol/l selectively inhibit the growth of 60 to 90 percent of the cancer tumor cells of the human myeloid leukemia (HL-60).

Material for electrodes of low temperature plasma generators

Science.gov (United States)

Caplan, Malcolm; Vinogradov, Sergel Evge'evich; Ribin, Valeri Vasil'evich; Shekalov, Valentin Ivanovich; Rutberg, Philip Grigor'evich; Safronov, Alexi Anatol'evich

2008-12-09

Material for electrodes of low temperature plasma generators. The material contains a porous metal matrix impregnated with a material emitting electrons. The material uses a mixture of copper and iron powders as a porous metal matrix and a Group IIIB metal component such as Y.sub.2O.sub.3 is used as a material emitting electrons at, for example, the proportion of the components, mass %: iron: 3-30; Y.sub.2O.sub.3:0.05-1; copper: the remainder. Copper provides a high level of heat conduction and electric conductance, iron decreases intensity of copper evaporation in the process of plasma creation providing increased strength and lifetime, Y.sub.2O.sub.3 provides decreasing of electronic work function and stability of arc burning. The material can be used for producing the electrodes of low temperature AC plasma generators used for destruction of liquid organic wastes, medical wastes, and municipal wastes as well as for decontamination of low level radioactive waste, the destruction of chemical weapons, warfare toxic agents, etc.

Effects of sodium nitroprusside (SNP) pretreatment on UV-B stress tolerance in lettuce (Lactuca sativa L.) seedlings.

Science.gov (United States)

Esringu, Aslıhan; Aksakal, Ozkan; Tabay, Dilruba; Kara, Ayse Aydan

2016-01-01

Ultraviolet-B (UV-B) radiation is one of the most important abiotic stress factors that could influence plant growth, development, and productivity. Nitric oxide (NO) is an important plant growth regulator involved in a wide variety of physiological processes. In the present study, the possibility of enhancing UV-B stress tolerance of lettuce seedlings by the exogenous application of sodium nitroprusside (SNP) was investigated. UV-B radiation increased the activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), peroxidase (POD) and total phenolic concentrations, antioxidant capacity, and expression of phenylalanine ammonia lyase (PAL) gene in seedlings, but the combination of SNP pretreatment and UV-B enhanced antioxidant enzyme activities, total phenolic concentrations, antioxidant capacity, and PAL gene expression even more. Moreover, UV-B radiation significantly inhibited chlorophylls, carotenoid, gibberellic acid (GA), and indole-3-acetic acid (IAA) contents and increased the contents of abscisic acid (ABA), salicylic acid (SA), malondialdehyde (MDA), hydrogen peroxide (H2O2), and superoxide radical (O2•(-)) in lettuce seedlings. When SNP pretreatment was combined with the UV-B radiation, we observed alleviated chlorophylls, carotenoid, GA, and IAA inhibition and decreased content of ABA, SA, MDA, H2O2, and O2•(-) in comparison to non-pretreated stressed seedlings.

Involvement of Sodium Nitroprusside (SNP in the Mechanism That Delays Stem Bending of Different Gerbera Cultivars

Directory of Open Access Journals (Sweden)

Aung H. Naing

2017-11-01

Full Text Available Longevity of cut flowers of many gerbera cultivars (Gerbera jamesonii is typically short because of stem bending; hence, stem bending that occurs during the early vase life period is a major problem in gerbera. Here, we investigated the effects of sodium nitroprusside (SNP on the delay of stem bending in the gerbera cultivars, Alliance, Rosalin, and Bintang, by examining relative fresh weight, bacterial density in the vase solution, transcriptional analysis of a lignin biosynthesis gene, antioxidant activity, and xylem blockage. All three gerbera cultivars responded to SNP by delaying stem bending, compared to the controls; however, the responses were dose- and cultivar-dependent. Among the treatments, SNP at 20 mg L-1 was the best to delay stem bending in Alliance, while dosages of 10 and 5 mg L-1 were the best for Rosalin and Bintang, respectively. However, stem bending in Alliance and Rosalin was faster than in Bintang, indicating a discrepancy influenced by genotype. According to our analysis of the role of SNP in the delay of stem bending, the results revealed that SNP treatment inhibited bacterial growth and xylem blockage, enhanced expression levels of a lignin biosynthesis gene, and maintained antioxidant activities. Therefore, it is suggested that the cause of stem bending is associated with the above-mentioned parameters and SNP is involved in the mechanism that delays stem bending in the different gerbera cultivars.

Thermophysical properties of copper compounds in copper-chlorine thermochemical water splitting cycles

International Nuclear Information System (INIS)

Zamfirescu, C.; Dincer, I.; Naterer, G.F.

2009-01-01

This paper examines the relevant thermophysical properties of compounds of chlorine and copper that are found in thermochemical water splitting cycles. There are four variants of such Cu-Cl cycles that use heat and electricity to split the water molecule and produce H 2 and O 2 . Since the energy input is mainly in the form of thermal energy, the Cu-Cl water splitting cycle is much more efficient than water electrolysis, if the electricity generation efficiency for electrolysis is taken into account. A number of copper compounds (Cu 2 OCl 2 , CuO, CuCl 2 , CuCl) and other chemicals (Cu, HCl) are recycled within the plant, while the overall effect is splitting of the water molecule. The system includes a number of chemical reactors, heat exchangers, spray dryer and electrochemical cell. This paper identifies the available experimental data for properties of copper compounds relevant to the Cu-Cl cycle analysis and design. It also develops new regression formulas to correlate the properties, which include: specific heat, enthalpy, entropy, Gibbs free energy, density, formation enthalpy and free energy. No past literature data is available for the viscosity and thermal conductivity of molten CuCl, so estimates are provided. The properties are evaluated at 1 bar and a range of temperatures from ambient to 675-1000K, which are consistent with the operating conditions of the cycle. Updated calculations of chemical exergies are provided as follows: 21.08, 6.268, 82.474, and 75.0 kJ/mol for Cu 2 OCl 2 , CuO, CuCl 2 and CuCl, respectively. For molten CuCl, the estimated viscosity varies from 2.6 to 1.7mPa.s. (author)

Oxalic acid overproduction by copper-tolerant brown-rot basidiomycetes on southern yellow pine treated with copper-based preservatives

Science.gov (United States)

Carol A. Clausen; Frederick Green

2003-01-01

Accumulation of oxalic acid (OA) by brown-rot fungi and precipitation of copper oxalate crystals in wood decayed by copper-tolerant decay fungi has implicated OA in the mechanism of copper tolerance. Understanding the role of OA in copper tolerance is important due to an increasing reliance on copper-based wood preservatives. In this study, four copper-tolerant brown-...

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)

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.

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

Science.gov (United States)

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

2005-09-01

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

Hepatic copper content, urinary copper excretion, and serum ceruloplasmin in liver disease. [Activation analysis

Energy Technology Data Exchange (ETDEWEB)

Ritland, S; Skrede, S [Rikshospitalet, Oslo (Norway); Steinnes, E [Institutt for Atomenergi, Kjeller (Norway)

1977-01-01

Liver copper content, urinary copper output and plasma ceruloplasmin have been evaluated in a variety of liver disorders. An activation analysis procedure for the determination of liver copper content is described. Dried biopsy samples were irradiated for two days at a thermal neutron flux of 1.5x10/sup 13/ ncm/sup -2/sec/sup -1/. After one day's delay the samples were dissolved in an acid mixture with copper carrier, and separated on an anion exchange column. The /sup 64/Cu activity in the separated fractions was recorded by gamma spectrometry using a Ge(Li) solid detector. The urinary copper excretion and the serum ceruloplasmin were determined by conventional laboratory methods.

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

NARCIS (Netherlands)

Berghe, van den P.V.E; Folmer, D.E.; Malingré, H.E.M.; Beurden, van E.; Klomp, A.E.M.; Sluis, van de B.; Merkx, M.; Berger, R.J.; Klomp, L.W.J.

2007-01-01

High-affinity cellular copper uptake is mediated by the CTR (copper transporter) 1 family of proteins. The highly homologous hCTR (human CTR) 2 protein has been identified, but its function in copper uptake is currently unknown. To characterize the role of hCTR2 in copper homoeostasis,

Cu,Zn-superoxide dismutase is lower and copper chaperone CCS is higher in erythrocytes of copper-deficient rats and mice.

Science.gov (United States)

West, Elizabeth C; Prohaska, Joseph R

2004-09-01

Discovery of a sensitive blood biochemical marker of copper status would be valuable for assessing marginal copper intakes. Rodent models were used to investigate whether erythrocyte concentrations of copper,zinc-superoxide dismutase (SOD), and the copper metallochaperone for SOD (CCS) were sensitive to dietary copper changes. Several models of copper deficiency were studied in postweanling male Holtzman rats, male Swiss Webster mice offspring, and both rat and mouse dams. Treatment resulted in variable but significantly altered copper status as evaluated by the presence of anemia, and lower liver copper and higher liver iron concentrations in copper-deficient compared with copper-adequate animals. Associated with this copper deficiency were consistent reductions in immunoreactive SOD and robust enhancements in CCS. In most cases, the ratio of CCS:SOD was several-fold higher in red blood cell extracts from copper-deficient compared with copper-adequate rodents. Determination of red cell CCS:SOD may be useful for assessing copper status of humans.

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.

Optics vs copper: from the perspective of "Thunderbolt" interconnect technology

Science.gov (United States)

Cheng, Hengju; Krause, Christine; Ko, Jamyuen; Gao, Miaobin; Liu, Guobin; Wu, Huichin; Qi, Mike; Lam, Chun-Chit

2013-02-01

Interconnect technology has been progressed at a very fast pace for the past decade. The signaling rates have steadily increased from 100:Mb/s to 25Gb/s. In every generation of interconnect technology evolution, optics always seems to take over at first, however, at the end, the cost advantage of copper wins over. Because of this, optical interconnects are limited to longer distance links where the attenuation in copper cable is too large for the integrated circuits to compensate. Optical interconnect has long been viewed as the premier solution in compared with copper interconnect. With the release of Thunderbolt technology, we are entering a new era in consumer electronics that runs at 10Gb/s line rate (20Gb/s throughput per connector interface). Thunderbolt interconnect technology includes both active copper cables and active optical cables as the transmission media which have very different physical characteristics. In order for optics to succeed in consumer electronics, several technology hurdles need to be cleared. For example, the optical cable needs to handle the consumer abuses such as pinch and bend. Also, the optical engine used in the active optical cable needs to be physically very small so that we don't change the looks and feels of the cable/connector. Most importantly, the cost of optics needs to come down significantly to effectively compete with the copper solution. Two interconnect technologies are compared and discussed on the relative cost, power consumption, form factor, density, and future scalability.

A novel application of the CuI thin film for preparing thin copper nanowires

International Nuclear Information System (INIS)

Shi Shuo; Sun Jialin; Zhang Jianhong; Cao Yang

2005-01-01

We present a novel application of the CuI thin film for preparing thin copper nanowires under a direct current electric field (DCEF). The CuI thin film was used as a medium for transmitting cuprous ions during the growing process of copper nanowires. As electrodes are the source of cuprous ions, high-purity copper films were deposited on both ends of the CuI thin film. At 353 K, under whole solid condition, without any templates, and having applied a DCEF of 1.5x10 4 V/m, cuprous ions were generated at the anode and migrated towards the cathode through the CuI film. At the edge of the cathode, cuprous ions obtained electrons and congregated to form a disordered thin copper nanowires bundle. The SEM images showed that these copper nanowires were from 10 to 20 nm in diameter and several hundred nanometers in length. The effect of the electric field intensity and the growth temperature on the diameter of the nanowires was also studied

Investigation of the interaction of copper(II) oxide and electron beam irradiation crosslinkable polyethylene

International Nuclear Information System (INIS)

Bee, Soo-Tueen; Sin, Lee Tin; Ratnam, C.T.; Haraveen, K.J.S.; Tee, Tiam-Ting; Rahmat, A.R.

2015-01-01

In this study, the effects of electron beam irradiation on the properties of copper(II) oxide when added to low-density polyethylene (LDPE) blends were investigated. It was found that the addition of low loading level of copper(II) oxide (⩽2 phr) to LDPE results in significantly poorer gel content and hot set results. However, the incorporation of higher loading level of copper(II) oxide (⩾3 phr) could slightly increase the degree of crosslinking in all irradiated LDPE composites. This is due to the fact that higher amounts of copper(II) oxide could slightly induce the formation of free radicals in LDPE matrix. Besides, increasing irradiation doses was also found to gradually increase the gel content of LDPE composites by generating higher amounts of free radicals. As a consequence, these higher amounts of free radicals released in the LDPE matrix could significantly increase the degree of crosslinking. The addition of copper(II) oxide could reduce the tensile strength and fracture strain (elongation at break) of LDPE composites because of poorer interfacial adhesion effect between copper(II) oxide particles and LDPE matrix. Meanwhile, increasing irradiation doses on all copper(II) oxide added LDPE composites could marginally increase the tensile strength. In addition, increasing irradiation dose could enhance the thermal stability of LDPE composites by increasing the decomposition temperature. The oxidation induction time (OIT) analysis showed that, because of the crosslinking network in the copper(II) oxide added LDPE composites, oxidation reaction is much delayed.

Investigation of the interaction of copper(II) oxide and electron beam irradiation crosslinkable polyethylene

Energy Technology Data Exchange (ETDEWEB)

Bee, Soo-Tueen, E-mail: direct.beest@gmail.com [Department of Chemical Engineering, Lee Kong Chian Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Jalan Sungai Long, Bandar Sungai Long, Cheras, 43000 Kajang, Selangor (Malaysia); Sin, Lee Tin, E-mail: direct.tinsin@gmail.com [Department of Chemical Engineering, Lee Kong Chian Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Jalan Sungai Long, Bandar Sungai Long, Cheras, 43000 Kajang, Selangor (Malaysia); Ratnam, C.T. [Radiation Processing Technology Division, Malaysian Nuclear Agency, Bangi, 43000 Kajang, Selangor (Malaysia); Haraveen, K.J.S.; Tee, Tiam-Ting [Department of Chemical Engineering, Lee Kong Chian Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Jalan Sungai Long, Bandar Sungai Long, Cheras, 43000 Kajang, Selangor (Malaysia); Rahmat, A.R. [Department of Polymer Engineering, Faculty of Chemical Engineering, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor (Malaysia)

2015-10-01

In this study, the effects of electron beam irradiation on the properties of copper(II) oxide when added to low-density polyethylene (LDPE) blends were investigated. It was found that the addition of low loading level of copper(II) oxide (⩽2 phr) to LDPE results in significantly poorer gel content and hot set results. However, the incorporation of higher loading level of copper(II) oxide (⩾3 phr) could slightly increase the degree of crosslinking in all irradiated LDPE composites. This is due to the fact that higher amounts of copper(II) oxide could slightly induce the formation of free radicals in LDPE matrix. Besides, increasing irradiation doses was also found to gradually increase the gel content of LDPE composites by generating higher amounts of free radicals. As a consequence, these higher amounts of free radicals released in the LDPE matrix could significantly increase the degree of crosslinking. The addition of copper(II) oxide could reduce the tensile strength and fracture strain (elongation at break) of LDPE composites because of poorer interfacial adhesion effect between copper(II) oxide particles and LDPE matrix. Meanwhile, increasing irradiation doses on all copper(II) oxide added LDPE composites could marginally increase the tensile strength. In addition, increasing irradiation dose could enhance the thermal stability of LDPE composites by increasing the decomposition temperature. The oxidation induction time (OIT) analysis showed that, because of the crosslinking network in the copper(II) oxide added LDPE composites, oxidation reaction is much delayed.

Copper tolerance and virulence in bacteria

Science.gov (United States)

Ladomersky, Erik; Petris, Michael J.

2015-01-01

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

Transpassive Dissolution of Copper and Rapid Formation of Brilliant Colored Copper Oxide Films

Science.gov (United States)

Fredj, Narjes; Burleigh, T. David; New Mexico Tech Team

2014-03-01

This investigation describes an electrochemical technique for growing adhesive copper oxide films on copper with attractive colors ranging from gold-brown to pearl with intermediate colors from red violet to gold green. The technique consists of anodically dissolving copper at transpassive potentials in hot sodium hydroxide, and then depositing brilliant color films of Cu2O onto the surface of copper after the anodic potential has been turned off. The color of the copper oxide film depends on the temperature, the anodic potential, the time t1 of polarization, and the time t2, which is the time of immersion after potential has been turned off. The brilliant colored films were characterized using glancing angle x-ray diffraction, and the film was found to be primarily Cu2O. Cyclic voltammetry, chronopotentiometry, scanning electron microscopy, and x-ray photoelectron spectroscopy were also used to characterize these films.

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)

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

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

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.

Copper-zinc superoxide dismutase is activated through a sulfenic acid intermediate at a copper ion entry site.

Science.gov (United States)

Fetherolf, Morgan M; Boyd, Stefanie D; Taylor, Alexander B; Kim, Hee Jong; Wohlschlegel, James A; Blackburn, Ninian J; Hart, P John; Winge, Dennis R; Winkler, Duane D

2017-07-21

Metallochaperones are a diverse family of trafficking molecules that provide metal ions to protein targets for use as cofactors. The copper chaperone for superoxide dismutase (Ccs1) activates immature copper-zinc superoxide dismutase (Sod1) by delivering copper and facilitating the oxidation of the Sod1 intramolecular disulfide bond. Here, we present structural, spectroscopic, and cell-based data supporting a novel copper-induced mechanism for Sod1 activation. Ccs1 binding exposes an electropositive cavity and proposed "entry site" for copper ion delivery on immature Sod1. Copper-mediated sulfenylation leads to a sulfenic acid intermediate that eventually resolves to form the Sod1 disulfide bond with concomitant release of copper into the Sod1 active site. Sod1 is the predominant disulfide bond-requiring enzyme in the cytoplasm, and this copper-induced mechanism of disulfide bond formation obviates the need for a thiol/disulfide oxidoreductase in that compartment. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Features of copper etching in chlorine-argon plasma

International Nuclear Information System (INIS)

Efremov, A.M.; Svettsov, V.I.

1995-01-01

Chlorine mixtures with inert gases including argon exhibit promise as plasma feed gases for etching metals and semiconductors in the microelectronics industry. It was shown that even strong dilution of reactive gas with an inert gas (up to 80-90% of the latter) has virtually no effect in decreasing the rate of plasma etching of materials such as silicon and gallium arsenide, compared to etching in pure chlorine. The principal reactive species responsible for etching these substrates are chlorine atoms therefore, a possible explanation of the effect is an increase in the rate of bulk generation of chlorine atoms in the presence of argon. In this work the authors studied the influence of argon on the rate of copper etching in chlorine, because copper, unlike the above substrates, reacts effectively not only with the atoms but with the ground-state molecules of chlorine

Trialkylphosphine-stabilized copper(I) gallium(III) phenylchalcogenolate complexes: crystal structures and generation of ternary semiconductors by thermolysis.

Science.gov (United States)

Kluge, Oliver; Krautscheid, Harald

2012-06-18

A series of organometallic trialkylphosphine-stabilized copper gallium phenylchalcogenolate complexes [(R(3)P)(m)Cu(n)Me(2-x)Ga(EPh)(n+x+1)] (R = Me, Et, (i)Pr, (t)Bu; E = S, Se, Te; x = 0, 1) has been prepared and structurally characterized by X-ray diffraction. From their molecular structures three groups of compounds can be distinguished: ionic compounds, ring systems, and cage structures. All these complexes contain one gallium atom bound to one or two methyl groups, whereas the number of copper atoms, and therefore the nuclearity of the complexes, is variable and depends mainly on size and amount of phosphine ligand used in synthesis. The Ga-E bonds are relatively rigid, in contrast to flexible Cu-E bonds. The lengths of the latter are controlled by the coordination number and steric influences. The Ga-E bond lengths depend systematically on the number of methyl groups bound to the gallium atom, with somewhat shorter bonds in monomethyl compounds compared to dimethyl compounds. Quantum chemical computations reproduce this trend and show furthermore that the rotation of one phenyl group around the Ga-E bond is a low energy process with two distinct minima, corresponding to two different conformations found experimentally. Mixtures of different types of chalcogen atoms on molecular scale are possible, and then ligand exchange reactions in solution lead to mixed site occupation. In thermogravimetric studies the complexes were converted into the ternary semiconductors CuGaE(2). The thermolysis reaction is completed at temperatures between 250 and 400 °C, typically with lower temperatures for the heavier chalcogens. Because of significant release of Me(3)Ga during the thermolysis process, and especially in case of copper excess in the precursor complexes, binary copper chalcogenides are obtained as additional thermolysis products. Quaternary semiconductors can be obtained from mixed chalcogen precursors.

21 CFR 73.1647 - Copper powder.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Copper powder. 73.1647 Section 73.1647 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1647 Copper powder. (a) Identity. (1) The color additive copper powder is a very fine free-flowing metallic powder prepared from virgin electrolytic copper. It...

Induction of ceruloplasmin synthesis by interleukin-1 in copper deficient and copper sufficient rats

International Nuclear Information System (INIS)

Barber, E.F.; Cousins, R.J.

1986-01-01

Ceruloplasmin (Cp) is a copper-containing plasma protein important in the body's acute phase defense system. In copper sufficient rats given two injections of interleukin-1 (IL-1) at 0 and 8 h, ceruloplasmin activity began to significantly increase within 6 h, but did not peak until at least 24 h. The 24 h stimulated activity was 84 +/- 2 umole p-phenylene diamine (pPD) oxidized x min -1 x L -1 compared to a control of 43 +/- 5. These rats were injected with 100uCi 3 H-leucine (ip) 2 h before sacrifice to label newly synthesized proteins. When the 3 H immunoprecipitated by rabbit anti-rat Cp serum is expressed as a percent of the 3 H precipitated by trichloroacetic acid (TCA), the basal Cp synthesis rate was 3% of the total serum protein synthesis. The rate of Cp synthesis peaked 12 h after IL-1 injection at 7% of total serum protein synthesis and by 24 h was back to the basal rate. In copper deficient rats, IL-1 given with copper induced pPD oxidase activity, while IL-1 given alone did not stimulate activity. The basal Cp synthesis rate in these rats was 3%, the same as in the copper sufficient rats. In copper deficient rats, the Cp synthesis rate was induced by IL-1 with or without an injection of copper. Therefore, if dietary copper is in short supply, then although Cp synthesis is induced by this mediator of host defense mechanisms, Cp cannot carry out its functions

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

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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.

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

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

Ursodeoxycholic acid suppresses mitochondria-dependent programmed cell death induced by sodium nitroprusside in SH-SY5Y cells

International Nuclear Information System (INIS)

Chun, Hong Sung; Low, Walter C.

2012-01-01

Although ursodeoxycholic acid (UDCA) and its highly water-soluble formula (Yoo's solution; YS) have been shown to prevent neuronal damage, the effects of UDCA or YS against Parkinson's disease (PD)-related dopaminergic cell death has not been studied. This study investigated the protective effects of UDCA and YS on sodium nitroprusside (SNP)-induced cytotoxicity in human dopaminergic SH-SY5Y cells. Both UDCA (50–200 μM) and YS (100–200 μM) dose-dependently prevented SNP (1 mM)-induced cell death. Results showed that both UDCA and YS effectively attenuated the production of total reactive oxygen species (ROS), peroxynitrite (ONOO − ) and nitric oxide (NO), and markedly inhibited the mitochondrial membrane potential (MMP) loss and intracellular reduced glutathione (GSH) depletion. SNP-induced programmed cell death events, such as nuclear fragmentation, caspase-3/7 and -9 activation, Bcl-2/Bax ratio decrease, and cytochrome c release, were significantly attenuated by both UDCA and YS. Furthermore, selective inhibitor of phosphatidylinositiol-3-kinase (PI3K), LY294002, and Akt/PKB inhibitor, triciribine, reversed the preventive effects of UDCA on the SNP-induced cytotoxicity and Bax translocation. These results suggest that UDCA can protect SH-SY5Y cells under programmed cell death process by regulating PI3K-Akt/PKB pathways.

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

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

Accumulation and hyperaccumulation of copper in plants

Science.gov (United States)

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

2009-04-01

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

Removal of copper from aqueous solution by electrodeposition in cathode chamber of microbial fuel cell.

Science.gov (United States)

Tao, Hu-Chun; Liang, Min; Li, Wei; Zhang, Li-Juan; Ni, Jin-Ren; Wu, Wei-Min

2011-05-15

Based on energetic analysis, a novel approach for copper electrodeposition via cathodic reduction in microbial fuel cells (MFCs) was proposed for the removal of copper and recovery of copper solids as metal copper and/or Cu(2)O in a cathode with simultaneous electricity generation with organic matter. This was examined by using dual-chamber MFCs (chamber volume, 1L) with different concentrations of CuSO(4) solution (50.3 ± 5.8, 183.3 ± 0.4, 482.4 ± 9.6, 1007.9 ± 52.0 and 6412.5 ± 26.7 mg Cu(2+)/L) as catholyte at pH 4.7, and different resistors (0, 15, 390 and 1000 Ω) as external load. With glucose as a substrate and anaerobic sludge as an inoculum, the maximum power density generated was 339 mW/m(3) at an initial 6412.5 ± 26.7 mg Cu(2+)/L concentration. High Cu(2+) removal efficiency (>99%) and final Cu(2+) concentration below the USA EPA maximum contaminant level (MCL) for drinking water (1.3mg/L) was observed at an initial 196.2 ± 0.4 mg Cu(2+)/L concentration with an external resistor of 15 Ω, or without an external resistor. X-ray diffraction analysis confirmed that Cu(2+) was reduced to cuprous oxide (Cu(2)O) and metal copper (Cu) on the cathodes. Non-reduced brochantite precipitates were observed as major copper precipitates in the MFC with a high initial Cu(2+) concentration (0.1M) but not in the others. The sustainability of high Cu(2+) removal (>96%) by MFC was further examined by fed-batch mode for eight cycles. Copyright © 2011 Elsevier B.V. All rights reserved.

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.

A Study of the Optimal Model of the Flotation Kinetics of Copper Slag from Copper Mine BOR

Science.gov (United States)

Stanojlović, Rodoljub D.; Sokolović, Jovica M.

2014-10-01

In this study the effect of mixtures of copper slag and flotation tailings from copper mine Bor, Serbia on the flotation results of copper recovery and flotation kinetics parameters in a batch flotation cell has been investigated. By simultaneous adding old flotation tailings in the ball mill at the rate of 9%, it is possible to increase copper recovery for about 20%. These results are compared with obtained copper recovery of pure copper slag. The results of batch flotation test were fitted by MatLab software for modeling the first-order flotation kinetics in order to determine kinetics parameters and define an optimal model of the flotation kinetics. Six kinetic models are tested on the batch flotation copper recovery against flotation time. All models showed good correlation, however the modified Kelsall model provided the best fit.

Unraveling the Amycolatopsis tucumanensis copper-resistome.

Science.gov (United States)

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

2012-10-01

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

Redox cycling of endogenous copper by ferulic acid leads to cellular DNA breakage and consequent cell death: A putative cancer chemotherapy mechanism

Energy Technology Data Exchange (ETDEWEB)

Sarwar, Tarique [Department of Biochemistry, Faculty of Life Sciences, A.M. University, Aligarh, UP 202002 (India); Zafaryab, Md [Genome Biology Lab, Department of Biosciences, Jamia Millia Islamia, Central University, New Delhi 110025 (India); Husain, Mohammed Amir; Ishqi, Hassan Mubarak; Rehman, Sayeed Ur [Department of Biochemistry, Faculty of Life Sciences, A.M. University, Aligarh, UP 202002 (India); Moshahid Alam Rizvi, M. [Genome Biology Lab, Department of Biosciences, Jamia Millia Islamia, Central University, New Delhi 110025 (India); Tabish, Mohammad, E-mail: tabish.bcmlab@gmail.com [Department of Biochemistry, Faculty of Life Sciences, A.M. University, Aligarh, UP 202002 (India)

2015-12-01

Ferulic acid (FA) is a plant polyphenol showing diverse therapeutic effects against cancer, diabetes, cardiovascular and neurodegenerative diseases. FA is a known antioxidant at lower concentrations, however at higher concentrations or in the presence of metal ions such as copper, it may act as a pro-oxidant. It has been reported that copper levels are significantly raised in different malignancies. Cancer cells are under increased oxidative stress as compared to normal cells. Certain therapeutic substances like polyphenols can further increase this oxidative stress and kill cancer cells without affecting the proliferation of normal cells. Through various in vitro experiments we have shown that the pro-oxidant properties of FA are enhanced in the presence of copper. Comet assay demonstrated the ability of FA to cause oxidative DNA breakage in human peripheral lymphocytes which was ameliorated by specific copper-chelating agent such as neocuproine and scavengers of ROS. This suggested the mobilization of endogenous copper in ROS generation and consequent DNA damage. These results were further validated through cytotoxicity experiments involving different cell lines. Thus, we conclude that such a pro-oxidant mechanism involving endogenous copper better explains the anticancer activities of FA. This would be an alternate non-enzymatic, and copper-mediated pathway for the cytotoxic activities of FA where it can selectively target cancer cells with elevated levels of copper and ROS. - Highlights: • Pro-oxidant properties of ferulic acid are enhanced in presence of copper. • Ferulic acid causes oxidative DNA damage in lymphocytes as observed by comet assay. • DNA damage was ameliorated by copper chelating agent neocuproine and ROS scavengers. • Endogenous copper is involved in ROS generation causing DNA damage. • Ferulic acid exerts cancer cell specific cytotoxicity as observed by MTT assay.

Liver mitochondrial dysfunction and electron transport chain defect induced by high dietary copper in broilers.

Science.gov (United States)

Yang, Fan; Cao, Huabin; Su, Rongsheng; Guo, Jianying; Li, Chengmei; Pan, Jiaqiang; Tang, Zhaoxin

2017-09-01

Copper is an important trace mineral in the diet of poultry due to its biological activity. However, limited information is available concerning the effects of high copper on mitochondrial dysfunction. In this study, 72 broilers were used to investigate the effects of high dietary copper on liver mitochondrial dysfunction and electron transport chain defect. Birds were fed with different concentrations [11, 110, 220, and 330 mg of copper/kg dry matter (DM)] of copper from tribasic copper chloride (TBCC). The experiment lasted for 60 d. Liver tissues on d 60 were subjected to histopathological observation. Additionally, liver mitochondrial function was recorded on d 12, 36, and 60. Moreover, a site-specific defect in the electron transport chain in liver mitochondria was also identified by using various chemical inhibitors of mitochondrial respiration. The results showed different degrees of degeneration, mitochondrial swelling, and high-density electrons in hepatocytes. In addition, the respiratory control ratio (RCR) and oxidative phosphorylation rate (OPR) in liver mitochondria increased at first and then decreased in high-dose groups. Moreover, hydrogen peroxide (H2O2) generation velocity in treated groups was higher than that in control group, which were magnified by inhibiting electron transport at Complex IV. The results indicated that high dietary copper could decline liver mitochondrial function in broilers. The presence of a site-specific defect at Complex IV in liver mitochondria may be responsible for liver mitochondrial dysfunction caused by high dietary copper. © 2017 Poultry Science Association Inc.

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 ...

Copper Powder and Chemicals: edited proceedings of a seminar

Energy Technology Data Exchange (ETDEWEB)

1980-12-01

Various papers are presented covering the following topics: Status of Copper Chemical Industry in India, Copper Powder from Industrial Wastes, Manufacture of Copper Hydroxide and High Grade Cement Copper from Low Grade Copper Ore, Manufacture of Copper Sulphate as a By-Product, Hydrometallurgical Treatments of Copper Converter and Smelter Slage for Recovering Copper and other Non-Ferrous Metals, Recovery of Copper from Dilute Solutions, Use of Copper Compounds as Fungicides in India, Copper in Animal Husbandry, and Use of Copper Powder and Chemicals for Marine Applications. The keynote paper given at the Seminar was on Conservation of Copper for Better Use.

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

21 CFR 184.1261 - Copper sulfate.

Science.gov (United States)

2010-04-01

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

Selective leaching process for the recovery of copper and zinc oxide from copper-containing dust.

Science.gov (United States)

Wu, Jun-Yi; Chang, Fang-Chih; Wang, H Paul; Tsai, Ming-Jer; Ko, Chun-Han; Chen, Chih-Cheng

2015-01-01

The purpose of this study was to develop a resource recovery procedure for recovering copper and zinc from dust produced by copper smelting furnaces during the manufacturing of copper-alloy wires. The concentrations of copper in copper-containing dust do not meet the regulation standards defined by the Taiwan Environmental Protection Administration; therefore, such waste is classified as hazardous. In this study, the percentages of zinc and copper in the dust samples were approximately 38.4% and 2.6%, respectively. To reduce environmental damage and recover metal resources for industrial reuse, acid leaching was used to recover metals from these inorganic wastes. In the first stage, 2 N of sulphuric acid was used to leach the dust, with pH values controlled at 2.0-3.0, and a solid-to-liquid ratio of 1:10. The results indicated that zinc extraction efficiency was higher than 95%. A selective acid leaching process was then used to recover the copper content of the residue after filtration. In the second stage, an additional 1 N of sulphuric acid was added to the suspension in the selective leaching process, and the pH value was controlled at 1.5-2.0. The reagent sodium hydroxide (2 N) was used as leachate at a pH greater than 7. A zinc hydroxide compound formed during the process and was recovered after drying. The yields for zinc and copper were 86.9-93.5% and 97.0-98.9%, respectively.

Increased sensitivity of apolipoprotein E knockout mice to copper-induced oxidative injury to the liver.

Science.gov (United States)

Chen, Yuan; Li, Bin; Zhao, Ran-ran; Zhang, Hui-feng; Zhen, Chao; Guo, Li

2015-04-10

Apolipoprotein E (ApoE) genotypes are related to clinical presentations in patients with Wilson's disease, indicating that ApoE may play an important role in the disease. However, our understanding of the role of ApoE in Wilson's disease is limited. High copper concentration in Wilson's disease induces excessive generation of free oxygen radicals. Meanwhile, ApoE proteins possess antioxidant effects. We therefore determined whether copper-induced oxidative damage differ in the liver of wild-type and ApoE knockout (ApoE(-/-)) mice. Both wild-type and ApoE(-/-) mice were intragastrically administered with 0.2 mL of copper sulfate pentahydrate (200 mg/kg; a total dose of 4 mg/d) or the same volume of saline daily for 12 weeks, respectively. Copper and oxidative stress markers in the liver tissue and in the serum were assessed. Our results showed that, compared with the wild-type mice administered with copper, TBARS as a marker of lipid peroxidation, the expression of oxygenase-1 (HO-1), NAD(P)H dehydrogenase, and quinone 1 (NQO1) significantly increased in the ApoE(-/-) mice administered with copper, meanwhile superoxide dismutase (SOD) activity significantly decreased. Thus, it is concluded that ApoE may protect the liver from copper-induced oxidative damage in Wilson's disease. Copyright © 2015 Elsevier Inc. All rights reserved.

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.

Native copper in Permian Mudstones from South Devon: A natural analogue of copper canisters for high-level radioactive waste

International Nuclear Information System (INIS)

Milodowski, A.E.; Styles, M.T.; Werme, L.; Oversby, V.M.

2001-01-01

Native copper (>99.9% Cu) sheets associated with complex uraniferous and vanadiferous concretions in Upper Permian Mudstones from south Devon (United Kingdom) have been studied as a 'natural analogue' for copper canisters designed to be used in the isolation of spent fuel and high-level radioactive wastes (HLW) for deep geological disposal. Detailed analysis demonstrates that the copper formed before the mudstones were compacted. The copper displays complex corrosion and alteration. The earliest alteration was to copper oxides, followed sequentially by the formation of copper arsenides, nickel arsenide and copper sulphide, and finally nickel arsenide accompanied by nickel-copper arsenide, copper arsenide and uranium silicates. Petrographic observations demonstrate that these alteration products also formed prior to compaction. Consideration of the published history for the region indicates that maximum compaction of the rocks will have occurred by at least the Lower Jurassic (i.e. over 176 Ma ago). Since that time the copper sheets have remained isolated by the compacted mudstones and were unaffected by further corrosion until uplift and exposure to present-day surface weathering

Recirculation of Chilean copper smelting dust with high impurities contents to the smelting process

Energy Technology Data Exchange (ETDEWEB)

Sano, H.; Fujisawa, T. [Nagoya Univ., Nagoya (Japan). EcoTopia Science Inst.; Montenegro, V. [Nagoya Univ., Nagoya (Japan). Dept. of Materials Science and Engineering

2007-07-01

Dust generated during the copper smelting process is generally stabilized using hydrometallurgical methods as it contains high concentrations of arsenic. In this laboratory study, dust was recirculated during the smelting process in order to recover more copper and decrease dust emissions while recovering more copper. The behaviour of impurities and their influence on matte quality was also investigated. Industrial matte, flue dust, slag, and copper concentrates from a Chilean smelter were used as test materials. Dust recirculation tests were conducted in a simulated electric furnace. Off-gases were collected in a reaction tube, and the condensed volatile matter, slag, and matte phases were analyzed for their elemental content by inductively coupled plasma atomic emission spectrometry. The distribution of arsenic (As); antimony (Sb), bismuth (Bi), lead (Pb), and zinc (Zn) were investigated by varying the amounts of dust recirculating to the smelting stage with 21 per cent of the oxygen. Results showed that distributions of all analyzed elements increased with recirculation. It was concluded that copper can be recovered using the dust recirculation technique. However, impurities may limit the efficacy of the dust recirculation process. 6 refs., 3 tabs., 4 figs.

Predictors of arterial blood pressure control during deliberate hypotension with sodium nitroprusside in children.

Science.gov (United States)

Spielberg, David R; Barrett, Jeffrey S; Hammer, Gregory B; Drover, David R; Reece, Tammy; Cohane, Carol A; Schulman, Scott R

2014-10-01

Sodium nitroprusside (SNP) is used to decrease arterial blood pressure (BP) during certain surgical procedures. There are limited data regarding efficacy of BP control with SNP. There are no data on patient and clinician factors that affect BP control. We evaluated the dose-response relationship of SNP in infants and children undergoing major surgery and performed a quantitative assessment of BP control. One hundred fifty-three subjects at 7 sites received a blinded infusion followed by open-label SNP during operative procedures requiring controlled hypotension. SNP was administered by continuous infusion and titrated to maintain BP control (mean arterial BP [MAP] within ±10% of clinician-defined target). BP was recorded using an arterial catheter. Statistical process control methodology was used to quantify BP control. A multivariable model assessed the effects of patient and procedural factors. BP was controlled an average 45.4% (SD 23.9%; 95% CI, 41.5%-49.18%) of the time. Larger changes in infusion rate were associated with worse BP control (7.99% less control for 1 μg·kg·min increase in average titration size, P = 0.0009). A larger difference between a patient's baseline and target MAP predicted worse BP control (0.93% worse control per 1-mm Hg increase in MAP difference, P = 0.0013). Both effects persisted in multivariable models. SNP was effective in reducing BP. However, BP was within the target range less than half of the time. No clinician or patient factors were predictive of BP control, although 2 inverse relationships were identified. These relationships require additional study and may be best coupled with exposure-response modeling to propose improved dosing strategies when using SNP for controlled hypotension in the pediatric population.

Chronic copper poisoning in lambs

Energy Technology Data Exchange (ETDEWEB)

Ross, D B

1964-08-08

This communication presented evidence of the elevation of plasma GOT (glutamic oxaloacetic transaminase or aspartate transaminase) concentration during the development of copper toxicity in some experimental lambs, and also demonstrated that plasma GOT concentration can be used to assess the course of the disease during treatment. A group of Kerry Hill lambs were fed 1 1/2 lb per day of a proprietary concentrate containing 40 parts of copper per million on a dry-matter basis in addition to hay and water ad lib. Data was included for the plasma GOT concentrations of the lambs, bled weekly after weaning from pasture to this diet. There was some variation between the individual lambs, and in one there was no increase in plasma GOT by the 20th week when all the surviving lambs were slaughtered. The concentrations of copper found in the caudate lobe of the liver and in the kidney cortex post mortem were given. The overall findings showed that the liver gave a reliable indication of the copper status of an animal whereas the kidney cortex copper concentration was a better criterion for the diagnosis of copper poisoning and was in agreement with the results of Eden, Todd, and Grocey and Thompson. Observations demonstrated the benefits resulting from the early diagnosis of chronic copper poisoning in lambs, when treatment of affected animals may be commenced before the haemolytic crisis develops. Treatment included reducing the copper intake and dosing with ammonium molybdate and sodium sulfate, and the plasma GOT concentration may be used to assess the rate of recovery. 4 references, 3 tables.

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

Similar stress responses are elicited by copper and ultraviolet radiation in the aquatic plant Lemna gibba: Implication of reactive oxygen species as common signals

International Nuclear Information System (INIS)

Babu, T.S.; Akhtar, T.A.; Lampi, M.A.; Tripuranthakam, S.; Dixon, D.G.; Greenberg, B.M.

2003-01-01

Metals and ultraviolet (UV) radiation are two environmental stressors that can cause damage to plants. These two types of stressors often impact simultaneously on plants and both are known to promote reactive oxygen species (ROS) production. However, little information is available on the potential parallel stress responses elicited by metals and UV radiation. Using the aquatic plant Lemna gibba, we found that copper and simulated solar radiation (SSR, a light source containing photosynthetically active radiation (PAR) and UV radiation) induced similar responses in the plants. Both copper and SSR caused ROS formation. The ROS levels were higher when copper was combined with SSR than when applied with PAR. Higher concentrations of copper plus PAR caused toxicity as monitored by diminished growth and chlorophyll content. This toxicity was more pronounced when copper was combined with SSR. Because the generation of ROS was also higher when copper was combined with SSR, we attributed this enhanced toxicity to elevated levels of ROS. In comparison to PAR-grown plants, SSR treated plants exhibited elevated levels of superoxide dismutase (SOD) and glutathione reductase (GR). These enzyme levels were further elevated under both PAR and SSR when copper was added at concentrations that generated ROS. Interestingly, copper treatment in the absence of SSR (i.e. copper plus PAR) induced synthesis of the same flavonoids as those observed in SSR without copper. Finally, addition of either dimethyl thiourea or GSH (two common ROS scavengers) lowered in vivo ROS production, alleviated toxicity and diminished induction of GR as well as accumulation of UV absorbing compounds. Thus, the potential of ROS being a common signal for acclimation to stress by both copper and UV can be considered. (author)

Copper toxicity in housed lambs

Energy Technology Data Exchange (ETDEWEB)

Adamson, A H; Valks, D A; Appleton, M A; Shaw, W B

1969-09-27

Copper toxicity among 170 lambs artificially reared indoors at High Mowthorpe NAAS Experimental Husbandry Farm is reported. Although only three lambs were lost it is not unreasonable to suggest that the liver copper levels of the lambs which were slaughtered would have been high and losses could have been much heavier had there been any further copper supplementation. Even a copper level of 20 ppm in lamb concentrates given to lambs reared artificially indoors is dangerous, and intakes of much less than 38 mg per lamb per day can be fatal if given of a prolonged period. 5 references, 1 table.

Induction of oxidative DNA damage by mesalamine in the presence of copper: A potential mechanism for mesalamine anticancer activity

International Nuclear Information System (INIS)

Zimmerman, Ryan P.; Jia, Zhenquan; Zhu, Hong; Vandjelovic, Nathan; Misra, Hara P.; Wang, Jianmin; Li, Yunbo

2011-01-01

Mesalamine is the first line pharmacologic intervention for patients with ulcerative colitis, and recent epidemiologic studies have demonstrated a protective association between therapeutic use of the drug and colorectal carcinoma. However, the mechanism by which this protection is afforded has yet to be elucidated. Because copper is found at higher than normal concentrations in neoplastic cell nuclei and is known to interact with phenolic compounds to generate reactive oxygen species, we investigated whether the reaction of mesalamine/copper was able to induce oxidative DNA strand breaks in φX-174 RF I plasmid DNA, and the various components of the mechanism by which the reaction occurred. Plasmid DNA strand breaks were induced by pharmacologically relevant concentrations of mesalamine in the presence of a micromolar concentration of Cu(II), and damage was inhibited by bathocuproinedisulfonic acid (BCS) and catalase. Further, we showed that the reaction of copper with mesalamine consumed molecular oxygen, which was inhibited by BCS. Electron paramagnetic resonance spectral analysis of the reaction of copper/mesalamine indicated the presence of the hydroxyl radical, which was inhibited by both BCS and catalase. This study demonstrates for the first time that through a copper-redox cycling mechanism, the copper-mediated oxidation of mesalamine is a pro-oxidant interaction that generates hydroxyl radicals which may participate in oxidative DNA damage. These results demonstrate a potential mechanism of the anticancer effects of mesalamine in patients with ulcerative colitis.

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.

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.

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).

Copper radical oxidases and related extracellular oxidoreductases of wood-decay Agaricomycetes

Science.gov (United States)

Phil Kersten; Dan Cullen

2014-01-01

Extracellular peroxide generation, a key component of oxidative lignocellulose degradation, has been attributed to various enzymes including the copper radical oxidases. Encoded by a family of structurally related sequences, the genes are widely distributed among wood decay fungi including three recently completed polypore genomes. In all cases, core catalytic residues...

“Pulling the plug” on cellular copper: The role of mitochondria in copper export

OpenAIRE

Leary, Scot C.; Winge, Dennis R.; Cobine, Paul A.

2008-01-01

Mitochondria contain two enzymes, Cu, Zn superoxide dismutase (Sod1) and cytochrome c oxidase (CcO), that require copper as a cofactor for their biological activity. The copper used for their metallation originates from a conserved, bioactive pool contained within the mitochondrial matrix, the size of which changes in response to either genetic or pharmacological manipulation of cellular copper status. Its dynamic nature implies molecular mechanisms exist that functionally couple mitochondria...

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.

2016-01-01

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

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

Scanning electrochemical microscopy for the fabrication of copper nanowires: Atomic contacts with quantized conductance, and molecular adsorption effect

International Nuclear Information System (INIS)

Janin, Marion; Ghilane, Jalal; Lacroix, Jean-Christophe

2012-01-01

Highlights: ► Electrochemistry and SECM to generate copper nanowires with quantized conductance. ► Stable atomic contacts lasting for several hundreds of seconds have been obtained. ► The quantized conductances are independent of the tip and gap size. ► The method allows contacts to be generated in the presence of chosen molecules. ► Four-electrode configuration opens the route to redox gated atomic contact. - Abstract: Scanning electrochemical microscopy, SECM, is proposed as a tool for the fabrication of copper nanowires. In a first step, configuration based on two electrodes, a platinum UME (cathode) and a copper substrate (anode), operating in the SECM configuration was employed. For nanowires generated in water the conductance changes stepwise and varies by integer values of the conductance quantum G 0 . The formation of atomic contacts is supported by the ohmic behavior of the I–V curve. It depends neither on the UME tip radius nor on the initial gap size between tip and substrate. Atomic contacts generated in aqueous solutions of sodium dodecyl sulfate (SDS) below the critical micellar concentration (CMC) have conductances below 1G 0 attributed to molecular adsorption on the contact. In some cases, the nanowires have low conductance, 0.01G 0 . The corresponding I–V curve shows tunneling rather than ohmic behavior, suggesting that molecular junctions are formed with a few surfactant molecules trapped between the two electrodes. Finally, copper nanowires with quantized conductance have been generated using the SECM operating in a four-electrode setup. Thanks to the reference electrode, this configuration leads to better control of the potential of each working electrode; this setup will make it possible to evaluate the conductance variation and/or modulation upon electrochemical stimuli.

Sequestration of chelated copper by structural Fe(II): Reductive decomplexation and transformation of Cu{sup II}-EDTA

Energy Technology Data Exchange (ETDEWEB)

He, Hongping [State Key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science & Engineering, Tongji University, Shanghai 200092 (China); Wu, Deli, E-mail: wudeli@tongji.edu.cn [State Key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science & Engineering, Tongji University, Shanghai 200092 (China); Zhao, Linghui [State Key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science & Engineering, Tongji University, Shanghai 200092 (China); Luo, Cong [School of Civil and Environmental Engineering, Georgia Institute of Technology, GA 30332 (United States); Dai, Chaomeng; Zhang, Yalei [State Key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science & Engineering, Tongji University, Shanghai 200092 (China)

2016-05-15

Highlights: • Structural Fe(II) was found to reveal high sequestration potential in various chelated copper. • Chelated copper was reduced to Cu(0) and Cu{sub 2}O by =Fe(II), whcih was oxidized to Fe{sub 2}O{sub 3}·H{sub 2}O. • Both electron transfer and surface =Fe(II) were found to be crucial during chelated copper reduction. • The indispensible role of reductive decomplexation was identified in chelated copper sequestration. - Abstract: Chelated coppers, such as Cu{sup II}-EDTA, are characteristically refractory and difficult to break down because of their high stability and solubility. Cu{sup II}–EDTA sequestration by structural Fe(II) (=Fe(II)) was investigated intensively in this study. Up to 101.21 mgCu(II)/gFe(II) was obtained by =Fe(II) in chelated copper sequestration under near neutral pH condition (pH 7.70). The mechanism of Cu{sup II}-EDTA sequestration by =Fe(II) was concluded as follows: 3Cu{sup II}–EDTA + 7=Fe(II) + 9H{sub 2}O → Cu(0) ↓ + Cu{sub 2}O ↓ (the major product) + 2Fe{sub 2}O{sub 3}·H{sub 2}O ↓ + 3Fe{sup II}–EDTA +14H{sup +} Novel results strongly indicate that Cu{sup II} reductive transformation induced by surface =Fe(II) was mainly responsible for chelated copper sequestration. Cu(0) generation was initially facilitated, and subsequent reduction of Cu(II) into Cu(I) was closely combined with the gradual increase of ORP (Oxidation-Reduction Potential). Cu-containing products were inherently stable, but Cu{sub 2}O would be reoxidized to Cu(II) with extra-aeration, resulting in the release of copper, which was beneficial to Cu reclamation. Concentration diminution of Cu{sup II}–EDTA within the electric double layer and competitive adsorption were responsible for the negative effects of Ca{sup 2+}, Mg{sup 2+}. By generating vivianite, PO{sub 4}{sup 3−} was found to decrease surface =Fe(II) content. This study is among the first ones to identify the indispensible role of reductive decomplexation in chelated copper

Nanoscale Copper and Copper Compounds for Advanced Device Applications

Science.gov (United States)

Chen, Lih-Juann

2016-12-01

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

The Protective Effect of Curcumin versus Sodium Nitroprusside on Intestinal Ischemia/Reperfusion Injury

Directory of Open Access Journals (Sweden)

Dalia M Saleh

2014-04-01

Full Text Available Objective: Intestinal ischemia/reperfusion (I/R injury is a signi and #64257;cant complication in abdominal vascular surgery. Various treatment modalities have been applied, however, the role of nitric oxide (NO in this type of injury is still controversial. Aim of the work: To compare the protective effect of curcumin vs sodium nitroprusside (SNP, NO donor on intestine and remote organs following intestinal I/R injury. Methods: Rats were divided into 4 groups (sham-control, I/R, curcumin+I/R, SNP+I/R. I/R was induced by 30 min clamping the superior mesenteric artery (SMA then 60 min reperfusion. Rats were pretreated with either curcumin (80 mg/kg/day with food for one week or SNP (5 mg/kg, i.p prior to I/R. Intestinal levels of malondialdehyde (MDA, Nitrite/nitrate, superoxide dismutase (SOD and reduced glutathione (GSH were measured. The sections from jejunum, lungs and liver were stained with hematoxylin and eosin (H and E for histopathological examination. Immunohistochemical stains for eNOS expression in the jejunum and cleaved caspase-3 for apoptosis in the lungs and liver were done. Results: I/R resulted in both local and remote organs in and #64258;ammation associated with signi and #64257;cant increase in MDA and nitrate/nitrite and significant decrease in SOD and GSH levels. These histological and biochemical changes were improved by pretreatment with curcumin and to less extent by SNP. Immunohistochemical examination showed significant decrease in eNOS activity in the I/R group which was improved by curcumin pretreatment not by SNP. Liver apoptosis was improved by curcumin while lung apoptosis was improved by SNP. Conclusion: Curcumin ameliorates I/R-induced local and remote organs damage through its anti-inflammatory and antiapoptotic effect. SNP may be beneficial in I/R injury but not as significant as curcumin. [J Interdiscipl Histopathol 2014; 2(2.000: 74-87

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.

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)

1994-12-31

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.

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

International Nuclear Information System (INIS)

Bhansali, S.; Sood, D.K.; Zmood, R.B.

1993-01-01

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 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 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

Total aerobic destruction of azo contaminants with nanoscale zero-valent copper at neutral pH: promotion effect of in-situ generated carbon center radicals.

Science.gov (United States)

Dong, Guohui; Ai, Zhihui; Zhang, Lizhi

2014-12-01

In this study, nanoscale zero-valent copper (nZVC) was synthesized with a facile solvothermal method and used for the aerobic removal of azo contaminants at neutral pH for the first time. We found that both Cu(I) and OH generated during the nZVC induced molecular oxygen activation process accounted for the rapid total destruction of azo contaminants in the nZVC/Air system, where nZVC could activate molecular oxygen to produce H2O2, and also release Cu(I) to break the -NN- bond of azo contaminants via the sandmeyer reaction for the generation of carbon center radicals. The in-situ generated carbon center radicals would then react with OH produced by the Cu(I) catalyzed decomposition of H2O2, resulting in the generation of low molecular weight organic acids and their subsequent mineralization. The indispensible role of Cu(I) catalyzed sandmeyer reaction and the promotion effect of in-situ generated carbon center radicals on the rapid total destruction of azo contaminants in the nZVC/Air system were confirmed by gas chromatography-mass spectrometry analysis. This study can deepen our understanding on the degradation of organic pollutant with molecular oxygen activated by zero valent metal, and also provide a new method to remove azo contaminants at neutral pH. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

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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.

Colloidal and electrochemical aspects of copper-CMP

Science.gov (United States)

Sun, Yuxia

Copper based interconnects with low dielectric constant layers are currently used to increase interconnect densities and reduce interconnect time delays in integrated circuits. The technology used to develop copper interconnects involves Chemical Mechanical Planarization (CMP) of copper films deposited on low-k layers (silica or silica based films), which is carried out using slurries containing abrasive particles. One issue using such a structure is copper contamination over dielectric layers (SiO2 film), if not reduced, this contamination will cause current leakage. In this study, the conditions conducive to copper contamination onto SiO2 films during Cu-CMP process were studied, and a post-CMP cleaning technique was discussed based on experimental results. It was found that the adsorption of copper onto a silica surface is kinetically fast (electrocoagulation was investigated to remove both copper and abrasive slurry particles simultaneously. For effluent containing ˜40 ppm dissolved copper, it was found that ˜90% dissolved copper was removed from the waste streams through electroplating and in-situ chemical precipitation. The amount of copper removed through plating is impacted by membrane surface charge, type/amount of complexing agents, and solid content in the slurry suspension. The slurry particles can be removed ˜90% within 2 hours of EC through multiple mechanisms.

Theft in Price-Volatile Markets: On the Relationship between Copper Price and Copper Theft

OpenAIRE

Sidebottom, A.; Belur, J.; Bowers, K.; Tompson, L.; Johnson, S. D.

2011-01-01

Recently, against a backdrop of general reductions in acquisitive crime, increases have been observed in the frequency of metal theft offences. This is generally attributed to increases in metal prices in response to global demand exceeding supply. The main objective of this article was to examine the relationship between the price of copper and levels of copper theft, focusing specifically on copper cable theft from the British railway network. Results indicated a significant positive correl...

Adsorption of copper from the sulphate solution of low copper contents using the cationic resin Amberlite IR 120

International Nuclear Information System (INIS)

Jha, Manis Kumar; Nghiem Van Nguyen; Lee, Jae-chun; Jeong, Jinki; Yoo, Jae-Min

2009-01-01

In view of the increasing importance of the waste processing and recycling to meet the strict environmental regulations, the present investigation reports an adsorption process using the cationic exchanger Amberlite IR 120 for the recovery/removal of copper from the synthetic sulphate solution containing copper ≤0.7 mg/mL similar to the CMP waste effluent of electronic industry. Various process parameters, viz. contact time, solution pH, resin dose, and acid concentration of eluant were investigated for the adsorption of copper from the effluents. The 99.99% copper was found to be adsorbed from the sulphate solution containing copper 0.3-0.7 mg/mL of solution (feed pH 5) at A/R ratio 100 and eq. pH 2.5 in contact time 14 min. The mechanism for the adsorption of copper was found to follow Langmuir isotherm and second order rate. From the loaded organic, copper was eluted effectively by 1.8 M sulphuric acid at A/R ratio 25. The raffinate obtained after the recovery copper could be disposed safely without affecting the environment.

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.

Effects of vacuum processing erbium dideuteride/ditritide films deposited on chromium underlays on copper substrates

International Nuclear Information System (INIS)

Provo, J.L.

1978-01-01

Thin films of erbium dideuteride/ditritide were experimentally produced on chromium underlays deposited on copper substrates. The chromium underlay is required to prevent erbium occluder/copper substrate alloying which inhibits hydriding. Data taken has shown that vacuum processing affects the erbium/chromium/copper interaction. With an in situ process in which underlay/occluder films are vacuum deposited onto copper substrates and hydrided with no air exposure between these steps, data indicates a minimum of 1500A of chromium is required for optimum hydriding. If films are vacuum deposited as above and air-exposed before hydriding, a minimum of 3000A of chromium was shown to be required for equivalent hydriding. Data suggests that the activation step (600 0 C for 1 hour) required for hydriding the film of the second type is responsible for the difference observed. Such underlay thickness parameters are important, with regard to heat transfer considerations in thin hydride targets used for neutron generation

Reparatory adaptation to copper-induced injury and occurrence of a copper-binding protein in the polycheate, Eudistylia vancouveri

Energy Technology Data Exchange (ETDEWEB)

Young, J.S.; Roesijadi, G.

1983-01-01

Chemically injured branchial pinnae of copper-treated polychaetes, Eudistylia vancouveri, regenerated while still exposed to copper. The first observations of pinna regeneration coincided with the apparent induction of a low molecular weight (approx.5000 daltons) copper-binding protein. This protein may play a role in the detoxification of copper and subsequent tissue regeneration. 7 references, 5 figures.

LIGNOCELLULOSE NANOCOMPOSITE CONTAINING COPPER SULFIDE

OpenAIRE

Sanchi Nenkova; Peter Velev; Mirela Dragnevska; Diyana Nikolova; Kiril Dimitrov

2011-01-01

Copper sulfide-containing lignocellulose nanocomposites with improved electroconductivity were obtained. Two methods for preparing the copper sulfide lignocellulose nanocomposites were developed. An optimization of the parameters for obtaining of the nanocomposites with respect to obtaining improved electroconductivity, economy, and lower quantities and concentration of copper and sulfur ions in waste waters was conducted. The mechanisms and schemes of delaying and subsequent connection of co...

Use of the vasodilator sodium nitroprusside during local hyperthermia: effects on tumor temperature and tumor response in a rat tumor model

International Nuclear Information System (INIS)

Krossnes, Baard Kronen; Mella, Olav; Dahl, Olav

1996-01-01

Purpose: The effect of a decrease in the mean arterial blood pressure (MAP) induced by sodium nitroprusside (SNP) on the tumor temperature during hyperthermia (HT), and on the cytotoxic effect of HT, was studied in the BT 4 An tumor transplanted to the hind limb of BD IX rats. Experiments with two different anesthetics, pentobarbital and the midazolam/fentanyl/fluanisone combination (MFF), were performed to secure reliable conclusions. Methods and Materials: In the tumor response experiments local waterbath HT at 44.0 deg. C was given for 60 min. Sodium nitroprusside was administered as a continuous intravenous infusion to lower the MAP to 60 or 80 mmHg during HT. In two other experiments the temperature at the base of the tumor during HT was measured before and during SNP infusion. In animals without tumor the temperature was measured subcutaneously on the foot during HT with or without SNP-induced hypotension. Results: When SNP was given to lower the MAP to 60 mmHg during HT in MFF anesthetized animals, the median tumor growth time (TGT) was 70 days, compared to 14.5 days in the HT alone group. The corresponding figures were 127 and 12.1 days with pentobarbital anesthesia. In the HT + SNP group, more than 40% cure was observed in both experiments. No cures were seen in any of the other groups. Hyperthermia alone prolonged the TGT slightly, whereas SNP given alone had no effect, compared to controls. When the MAP was lowered to 80 mmHg by SNP infusion during HT (MFF anesthesia), the median TGT was 19.9 days, which was significantly longer than that in the HT alone group (10.9 days). In the MAP range from 60 to 120 mmHg, a nearly linear relationship between the MAP and the tumor temperature was found during HT in MFF anesthetized animals. With both anesthetics, the median temperature at the base of the tumor was about 0.8 deg. C higher during HT when the MAP was lowered to 60 mmHg by SNP. In animals without tumors, the temperature subcutaneously on the foot was 0

Synergetic effect of copper-plating wastewater as a catalyst for the destruction of acrylonitrile wastewater in supercritical water oxidation

Energy Technology Data Exchange (ETDEWEB)

Shin, Young Ho; Lee, Hong-shik; Lee, Young-Ho [School of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University, 599 Gwanangno, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Kim, Jaehoon; Kim, Jae-Duck [Supercritical Fluid Research Laboratory, Energy and Environment Research Division, Korea Institute of Science and Technology (KIST), 39-1 Hawolgok-dong, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); Lee, Youn-Woo, E-mail: ywlee@snu.ac.kr [School of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University, 599 Gwanangno, Gwanak-gu, Seoul 151-744 (Korea, Republic of)

2009-08-15

A new supercritical water oxidation process for the simultaneous treatment of mixed wastewater containing wastewater from acrylonitrile manufacturing processes and copper-plating processes was investigated using a continuous tubular reactor system. Experiments were carried out at temperatures ranging from 400 to 600 deg. C and a pressure of 25 MPa. The residence time was fixed at 2 s by changing the flow rates of feeds, depending on reaction temperature. The initial total organic carbon (TOC) concentration of the wastewaters and the O{sub 2} concentration at the reactor inlet were kept constant at 0.49 and 0.74 mol/L. It was confirmed that the copper-plating wastewater accelerated the TOC conversion of acrylonitrile wastewater from 17.6% to 67.3% at a temperature of 450 deg. C. Moreover, copper and copper oxide nanoparticles were generated in the process of supercritical water oxidation (SCWO) of mixed wastewater. 99.8% of copper in mixed wastewater was recovered as solid copper and copper oxides at a temperature of 600 deg. C, with their average sizes ranging from 150 to 160 nm. Our study showed that SCWO provides a synergetic effect for simultaneous treatment of acrylonitrile and copper-plating wastewater. During the reaction, the oxidation rate of acrylonitrile wastewater was enhanced due to the in situ formation of nano-catalysts of copper and/or copper oxides, while the exothermic decomposition of acrylonitrile wastewater supplied enough heat for the recovery of solid copper and copper oxides from copper-plating wastewater. The synergetic effect of wastewater treatment by the newly proposed SCWO process leads to full TOC conversion, color removal, detoxification, and odor elimination, as well as full recovery of copper.

Copper deficiency alters cell bioenergetics and induces mitochondrial fusion through up-regulation of MFN2 and OPA1 in erythropoietic cells

International Nuclear Information System (INIS)

Bustos, Rodrigo I.; Jensen, Erik L.; Ruiz, Lina M.; Rivera, Salvador; Ruiz, Sebastián; Simon, Felipe; Riedel, Claudia; Ferrick, David; Elorza, Alvaro A.

2013-01-01

Highlights: •In copper deficiency, cell proliferation is not affected. In turn, cell differentiation is impaired. •Enlarged mitochondria are due to up-regulation of MNF2 and OPA1. •Mitochondria turn off respiratory chain and ROS production. •Energy metabolism switch from mitochondria to glycolysis. -- Abstract: Copper is essential in cell physiology, participating in numerous enzyme reactions. In mitochondria, copper is a cofactor for respiratory complex IV, the cytochrome c oxidase. Low copper content is associated with anemia and the appearance of enlarged mitochondria in erythropoietic cells. These findings suggest a connection between copper metabolism and bioenergetics, mitochondrial dynamics and erythropoiesis, which has not been explored so far. Here, we describe that bathocuproine disulfonate-induced copper deficiency does not alter erythropoietic cell proliferation nor induce apoptosis. However it does impair erythroid differentiation, which is associated with a metabolic switch between the two main energy-generating pathways. That is, from mitochondrial function to glycolysis. Switching off mitochondria implies a reduction in oxygen consumption and ROS generation along with an increase in mitochondrial membrane potential. Mitochondrial fusion proteins MFN2 and OPA1 were up-regulated along with the ability of mitochondria to fuse. Morphometric analysis of mitochondria did not show changes in total mitochondrial biomass but rather bigger mitochondria because of increased fusion. Similar results were also obtained with human CD34+, which were induced to differentiate into red blood cells. In all, we have shown that adequate copper levels are important for maintaining proper mitochondrial function and for erythroid differentiation where the energy metabolic switch plus the up-regulation of fusion proteins define an adaptive response to copper deprivation to keep cells alive

Copper deficiency alters cell bioenergetics and induces mitochondrial fusion through up-regulation of MFN2 and OPA1 in erythropoietic cells

Energy Technology Data Exchange (ETDEWEB)

Bustos, Rodrigo I.; Jensen, Erik L.; Ruiz, Lina M.; Rivera, Salvador; Ruiz, Sebastián [Center for Biomedical Research, Faculty of Biological Sciences and Faculty of Medicine, Universidad Andres Bello, Santiago (Chile); Simon, Felipe; Riedel, Claudia [Center for Biomedical Research, Faculty of Biological Sciences and Faculty of Medicine, Universidad Andres Bello, Santiago (Chile); Millennium Institute of Immunology and Immunotherapy, Santiago (Chile); Ferrick, David [Seahorse Bioscience, Billerica, MA (United States); Elorza, Alvaro A., E-mail: aelorza@unab.cl [Center for Biomedical Research, Faculty of Biological Sciences and Faculty of Medicine, Universidad Andres Bello, Santiago (Chile); Millennium Institute of Immunology and Immunotherapy, Santiago (Chile)

2013-08-02

Highlights: •In copper deficiency, cell proliferation is not affected. In turn, cell differentiation is impaired. •Enlarged mitochondria are due to up-regulation of MNF2 and OPA1. •Mitochondria turn off respiratory chain and ROS production. •Energy metabolism switch from mitochondria to glycolysis. -- Abstract: Copper is essential in cell physiology, participating in numerous enzyme reactions. In mitochondria, copper is a cofactor for respiratory complex IV, the cytochrome c oxidase. Low copper content is associated with anemia and the appearance of enlarged mitochondria in erythropoietic cells. These findings suggest a connection between copper metabolism and bioenergetics, mitochondrial dynamics and erythropoiesis, which has not been explored so far. Here, we describe that bathocuproine disulfonate-induced copper deficiency does not alter erythropoietic cell proliferation nor induce apoptosis. However it does impair erythroid differentiation, which is associated with a metabolic switch between the two main energy-generating pathways. That is, from mitochondrial function to glycolysis. Switching off mitochondria implies a reduction in oxygen consumption and ROS generation along with an increase in mitochondrial membrane potential. Mitochondrial fusion proteins MFN2 and OPA1 were up-regulated along with the ability of mitochondria to fuse. Morphometric analysis of mitochondria did not show changes in total mitochondrial biomass but rather bigger mitochondria because of increased fusion. Similar results were also obtained with human CD34+, which were induced to differentiate into red blood cells. In all, we have shown that adequate copper levels are important for maintaining proper mitochondrial function and for erythroid differentiation where the energy metabolic switch plus the up-regulation of fusion proteins define an adaptive response to copper deprivation to keep cells alive.

The trade-off of availability and growth inhibition through copper for the production of copper-dependent enzymes by Pichia pastoris.

Science.gov (United States)

Balakumaran, Palanisamy Athiyaman; Förster, Jan; Zimmermann, Martin; Charumathi, Jayachandran; Schmitz, Andreas; Czarnotta, Eik; Lehnen, Mathias; Sudarsan, Suresh; Ebert, Birgitta E; Blank, Lars Mathias; Meenakshisundaram, Sankaranarayanan

2016-02-20

Copper is an essential chemical element for life as it is a part of prosthetic groups of enzymes including super oxide dismutase and cytochrome c oxidase; however, it is also toxic at high concentrations. Here, we present the trade-off of copper availability and growth inhibition of a common host used for copper-dependent protein production, Pichia pastoris. At copper concentrations ranging from 0.1 mM (6.35 mg/L) to 2 mM (127 mg/L), growth rates of 0.25 h(-1) to 0.16 h(-1) were observed with copper uptake of as high as 20 mgcopper/gCDW. The intracellular copper content was estimated by subtracting the copper adsorbed on the cell wall from the total copper concentration in the biomass. Higher copper concentrations led to stronger cell growth retardation and, at 10 mM (635 mg/L) and above, to growth inhibition. To test the determined copper concentration range for optimal recombinant protein production, a laccase gene from Aspergillus clavatus [EMBL: EAW07265.1] was cloned under the control of the constitutive glyceraldehyde-3-phosphate (GAP) dehydrogenase promoter for expression in P. pastoris. Notably, in the presence of copper, laccase expression improved the specific growth rate of P. pastoris. Although copper concentrations of 0.1 mM and 0.2 mM augmented laccase expression 4 times up to 3 U/mL compared to the control (0.75 U/mL), while higher copper concentrations resulted in reduced laccase production. An intracellular copper content between 1 and 2 mgcopper/gCDW was sufficient for increased laccase activity. The physiology of the yeast could be excluded as a reason for the stop of laccase production at moderate copper concentrations as no flux redistribution could be observed by (13)C-metabolic flux analysis. Copper and its pivotal role to sustain cellular functions is noteworthy. However, knowledge on its cellular accumulation, availability and distribution for recombinant protein production is limited. This study attempts to address one such challenge

Test data on electrical contacts at high surface velocities and high current densities for homopolar generators

International Nuclear Information System (INIS)

Brennan, M.; Tolk, K.M.; Weldon, W.F.; Rylander, H.G.; Woodson, H.H.

1977-01-01

Test data is presented for one grade of copper graphite brush material, Morganite CMlS, over a wide range of surface velocities, atmospheres, and current densities that are expected for fast discharge (<100 ms) homopolar generators. The brushes were run on a copper coated 7075-T6 aluminum disk at surface speeds up to 277 m/sec. One electroplated copper and three flame sprayed copper coatings were used during the tests. Significant differences in contact voltage drops and surface mechanical properties of the copper coatings were observed

Glutamate-Mediated Primary Somatosensory Cortex Excitability Correlated with Circulating Copper and Ceruloplasmin

Directory of Open Access Journals (Sweden)

Franca Tecchio

2011-01-01

Full Text Available Objective. To verify whether markers of metal homeostasis are related to a magnetoencephalographic index representative of glutamate-mediated excitability of the primary somatosensory cortex. The index is identified as the source strength of the earliest component (M20 of the somatosensory magnetic fields (SEFs evoked by right median nerve stimulation at wrist. Method. Thirty healthy right-handed subjects (51±22 years were enrolled in the study. A source reconstruction algorithm was applied to assess the amount of synchronously activated neurons subtending the M20 and the following SEF component (M30, which is generated by two independent contributions of gabaergic and glutamatergic transmission. Serum copper, ceruloplasmin, iron, transferrin, transferrin saturation, and zinc levels were measured. Results. Total copper and ceruloplasmin negatively correlated with the M20 source strength. Conclusion. This pilot study suggests that higher level of body copper reserve, as marked by ceruloplasmin variations, parallels lower cortical glutamatergic responsiveness.

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.

Multilevel Dual Damascene copper interconnections

Science.gov (United States)

Lakshminarayanan, S.

Copper has been acknowledged as the interconnect material for future generations of ICs to overcome the bottlenecks on speed and reliability present with the current Al based wiring. A new set of challenges brought to the forefront when copper replaces aluminum, have to be met and resolved to make it a viable option. Unit step processes related to copper technology have been under development for the last few years. In this work, the application of copper as the interconnect material in multilevel structures with SiO2 as the interlevel dielectric has been explored, with emphasis on integration issues and complete process realization. Interconnect definition was achieved by the Dual Damascene approach using chemical mechanical polishing of oxide and copper. The choice of materials used as adhesion promoter/diffusion barrier included Ti, Ta and CVD TiN. Two different polish chemistries (NH4OH or HNO3 based) were used to form the interconnects. The diffusion barrier was removed during polishing (in the case of TiN) or by a post CMP etch (as with Ti or Ta). Copper surface passivation was performed using boron implantation and PECVD nitride encapsulation. The interlevel dielectric way composed of a multilayer stack of PECVD SiO2 and SixNy. A baseline process sequence which ensured the mechanical and thermal compatibility of the different unit steps was first created. A comprehensive test vehicle was designed and test structures were fabricated using the process flow developed. Suitable modifications were subsequently introduced in the sequence as and when processing problems were encountered. Electrical characterization was performed on the fabricated devices, interconnects, contacts and vias. The structures were subjected to thermal stressing to assess their stability and performance. The measurement of interconnect sheet resistances revealed lower copper loss due to dishing on samples polished using HNO3 based slurry. Interconnect resistances remained stable upto 400o

Activation determination of copper in food

International Nuclear Information System (INIS)

Jiranek, V.; Bludovsky, R.

1982-01-01

Neutron activation analysis was used for determining copper content in food. Analyzed were dried milk, flour, coffee, tea, husked rice, and liver. Bowen's kale powder with a guaranteed copper content of 3.6 to 6.5 ppm was used as a reference biological material. The instruments, chemicals and solutions used are reported. The method is described of copper separation with α-benzoinoxime and pyridine as is the procedure for the destructive activation analysis of samples. The copper concentrations in the foods under analysis were found to range within usual limits. The copper concentration determined in the reference material agreed with the measured value. The analysis confirms that the method yields reliable results. (J.B.)

Chronic copper poisoning. III. Effects of copper acetate injected into the bloodstream of sheep

Energy Technology Data Exchange (ETDEWEB)

Todd, J R; Thompson, R H

1964-01-01

A study was made of the clinical and biochemical effects of injections of copper (as acetate) into the bloodstream of sheep of 100 to 130 lb. liveweight. Copper in a dose of 160 mg. caused death in 3 sheep in a few hours, and 80 mg. caused death in 3 out of 4 sheep, 2 after 2 days and 1 after 11 days. Symptoms, biochemical lesions and post-mortem appearances did not resemble those of chronic copper poisoning, but rather those of gastro-enteritis. Blood glutathione concentrations were not markedly reduced, but haemoconcentration was a prominent feature. Post-mortem examination showed gross congestion of blood vessels and marked inflammatory reactions in the abomasum and small intestine. Single injections of smaller amounts (25 to 40 mg. copper) were tolerated without effect, but repeated injections, twice daily for 2 to 3 days, caused haemolytic episodes in 3 sheep similar to the crisis of chronic copper poisoning in that a marked reduction in blood glutathione concentration and accumulation of methaemoglobin occurred. No other clinical effects were produced, however, and all three animals recovered uneventfully.

LIGNOCELLULOSE NANOCOMPOSITE CONTAINING COPPER SULFIDE

Directory of Open Access Journals (Sweden)

Sanchi Nenkova

2011-04-01

Full Text Available Copper sulfide-containing lignocellulose nanocomposites with improved electroconductivity were obtained. Two methods for preparing the copper sulfide lignocellulose nanocomposites were developed. An optimization of the parameters for obtaining of the nanocomposites with respect to obtaining improved electroconductivity, economy, and lower quantities and concentration of copper and sulfur ions in waste waters was conducted. The mechanisms and schemes of delaying and subsequent connection of copper sulfides in the lignocellulosic matrix were investigated. The modification with a system of 2 components: cupric sulfate pentahydrate (CuSO4. 5H2O and sodium thiosulfate pentahydrate (Na2S2O3.5H2O for wood fibers is preferred. Optimal parameters were established for the process: 40 % of the reduction system; hydromodule M=1:6; and ratio of cupric sulfate pentahydrate:sodium thiosulfate pentahydrate = 1:2. The coordinative connection of copper ions with oxygen atoms of cellulose OH groups and aromatic nucleus in lignin macromolecule was observed.

Mesophilic leaching of copper sulphide sludge

Directory of Open Access Journals (Sweden)

VLADIMIR B. CVETKOVSKI

2009-02-01

Full Text Available Copper was precipitated using a sodium sulphide solution as the precipitation agent from an acid solution containing 17 g/l copper and 350 g/l sulphuric acid. The particle size of nearly 1 µm in the sulphide sludge sample was detected by optical microscopy. Based on chemical and X-ray diffraction analyses, covellite was detected as the major sulphide mineral. The batch bioleach amenability test was performed at 32 °C on the Tk31 mine mesophilic mixed culture using a residence time of 28 days. The dissolution of copper sulphide by direct catalytic leaching of the sulphides with bacteria attached to the particles was found to be worthy, although a small quantity of ferrous ions had to be added to raise the activity of the bacteria and the redox potential of the culture medium. Throughout the 22-day period of the bioleach test, copper recovery based on residue analysis indicated a copper extraction of 95 %, with copper concentration in the bioleach solution of 15 g/l. The slope of the straight line tangential to the exponential part of the extraction curve gave a copper solubilisation rate of 1.1 g/l per day. This suggests that a copper extraction of 95 % for the period of bioleach test of 13.6 days may be attained in a three-stage bioreactor system.

Finishing of precision generated metal optical components

International Nuclear Information System (INIS)

Baker, P.C.; Sonderman, J.B.

1975-08-01

Diamond turning and precision generation of aspheric metal surfaces has promoted a change in lapping techniques due to the extremely close figure tolerances and surface finishes that have been achieved. Special tooling, diamond abrasive, silicon oil and special techniques used to polish the unusual aspheric figures are described. The studies include small flat diamond turned samples of copper, electroplated copper, electroplated silver, electroplated nickel and silver as well as large aspheres such as an f/0.75, 35 cm dia copper ellipse. Results from cleaning studies on flat samples using ultrasonics and vapor degreasers are also summarized. Interferograms of wavefront distortion and analysis of focal volume are included as well as 10.6 μm reflectivity and a summary of laser damage experiments. (TFD)

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)

VARIABILITY OF COORDINATION COMPLEXES OF COPPER ACCUMULATED WITHIN FUNGAL COLONY IN THE PRESENCE OF COPPER-CONTAINING MINERALS

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M. O. Fomina

2014-04-01

Full Text Available The aim of work was to elucidate the mechanisms of bioaccumulation of copper leached from minerals by fungus Aspergillus niger with great bioremedial potential due to its ability to produce chelating metabolites and transform toxic metals and minerals. The special attention was paid to the chemical speciation of copper bioaccumulated within fungal colony in the process of fungal transformation of copper-containing minerals. Chemical speciation of copper within different parts of the fungal colony was studied using solid-state chemistry methods such as synchrotron-based X-ray absorption spectroscopy providing information about the oxidation state of the target element, and its coordination environment. The analysis of the obtained X-ray absorption spectroscopy spectra was carried out using Fourier transforms of Extended X-ray Absorption Fine Structure regions, which correspond to the oscillating part of the spectrum to the right of the absorption edge. Results of this study showed that fungus A. niger was involved in the process of solubilization of copper-containing minerals resulted in leaching of mobile copper and its further immobilization by fungal biomass with variable coordination of accumulated copper within fungal colony which depended on the age and physiological/reproductive state of fungal mycelium. X-ray absorption spectroscopy data demonstrated that copper accumulated within outer zone of fungal colony with immature vegetative mycelium was coordinated with sulphur–containing ligands, in contrast to copper coordination with phosphate ligands within mature mycelium with profuse conidia in the central zone of the colony. The findings of this study not only broaden our understanding of the biogeochemical role of fungi but can also be used in the development of various fungal-based biometallurgy technologies such as bioremediation, bioaccumulation and bioleaching and in the assessment of their reliability. The main conclusion is that

21 CFR 74.3045 - [Phthalocyaninato(2-)] copper.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false [Phthalocyaninato(2-)] copper. 74.3045 Section 74...-)] copper. (a) Identity. The color additive is [phthalocyaninato(2-)] copper (CAS Reg. No. 147-14-8) having... [phthalocyaninato(2-)] copper shall conform to the following specifications and shall be free from impurities other...

Oxidation-assisted graphene heteroepitaxy on copper foil.

Science.gov (United States)

Reckinger, Nicolas; Tang, Xiaohui; Joucken, Frédéric; Lajaunie, Luc; Arenal, Raul; Dubois, Emmanuel; Hackens, Benoît; Henrard, Luc; Colomer, Jean-François

2016-11-10

We propose an innovative, easy-to-implement approach to synthesize aligned large-area single-crystalline graphene flakes by chemical vapor deposition on copper foil. This method doubly takes advantage of residual oxygen present in the gas phase. First, by slightly oxidizing the copper surface, we induce grain boundary pinning in copper and, in consequence, the freezing of the thermal recrystallization process. Subsequent reduction of copper under hydrogen suddenly unlocks the delayed reconstruction, favoring the growth of centimeter-sized copper (111) grains through the mechanism of abnormal grain growth. Second, the oxidation of the copper surface also drastically reduces the nucleation density of graphene. This oxidation/reduction sequence leads to the synthesis of aligned millimeter-sized monolayer graphene domains in epitaxial registry with copper (111). The as-grown graphene flakes are demonstrated to be both single-crystalline and of high quality.

Electroforming copper targets for RTNS-II

International Nuclear Information System (INIS)

Kelley, W.K.; Dini, J.W.; Logan, C.M.

1981-01-01

Copper targets used in RTNS II, which is the world's most intense 14-MeV neutron source, contain water cooling channels for temperature control. There are two methods for fabricating these targets: (1) diffusion bonding a copper panel containing photoetched channels to another copper panel, and (2) an electroforming technique which involves filling the photoetched channels with wax, plating thick copper to seal over the channels and then removing the wax. Development of this latter process and results obtained with it are described

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.

Carbohydrate metabolism in erythrocytes of copper deficient rats.

Science.gov (United States)

Brooks, S P J; Cockell, K A; Dawson, B A; Ratnayake, W M N; Lampi, B J; Belonje, B; Black, D B; Plouffe, L J

2003-11-01

Dietary copper deficiency is known to adversely affect the circulatory system of fructose-fed rats. Part of the problem may lie in the effect of copper deficiency on intermediary metabolism. To test this, weanling male Long-Evans rats were fed for 4 or 8 weeks on sucrose-based diets containing low or adequate copper content. Copper deficient rats had significantly lower plasma and tissue copper as well as lower plasma copper, zinc-superoxide dismutase activity. Copper deficient rats also had a significantly higher heart:body weight ratio when compared to pair-fed controls. Direct measurement of glycolysis and pentose phosphate pathway flux in erythrocytes using (13)C NMR showed no differences in carbon flux from glucose or fructose to pyruvate but a significantly higher flux through the lactate dehydrogenase locus in copper deficient rats (approximately 1.3 times, average of glucose and glucose + fructose measurements). Copper-deficient animals had significantly higher erythrocyte concentrations of glucose, fructose, glyceraldehyde 3-phosphate and NAD(+). Liver metabolite levels were also affected by copper deficiency being elevated in glycogen and fructose 1-phosphate content. The results show small changes in carbohydrate metabolism of copper deficient rats.

Dissolution of copper and iron from malachite ore and precipitation of copper sulfate pentahydrate by chemical process

Directory of Open Access Journals (Sweden)

H. Kokes

2014-03-01

Full Text Available The present work describes an investigation of a chemical process for the recovery of copper and iron from malachite ore. For the dissolution of copper and iron, H2SO4 was employed as well as H2O2 as an oxidizing agent. The effects of reaction temperature and time, acid concentration, liquid-to-solid ratio and agitation rate on the copper and iron percentage were investigated. Following the steps of dissolving the copper and iron sulfate and filtering, iron (III hydroxide was precipitated by adjusting the pH level of the solution. Subsequently, copper sulfate pentahydrate was obtained by using various precipitants (i.e. ethanol, methanol and sulfuric acid.

Homogeneous weldings of copper

International Nuclear Information System (INIS)

Campurri, C.; Lopez, M.; Fernandez, R.; Osorio, V.

1995-01-01

This research explored the metallurgical and mechanical properties of arc welding of copper related with influence of Argon, Helium and mixtures of them. Copper plates of 6 mm thickness were welded with different mixtures of the mentioned gases. The radiography of welded specimens with 100% He and 100% Ar does not show show any porosity. On the other hand, the copper plates welded different gas mixtures presented uniform porosity in the welded zone. The metallographies show recrystallized grain in the heat affected zone, while the welding zone showed a dendritic structure. The results of the tensile strength vary between a maximum of 227 MPa for 100% He and a minimum of 174 MOa for the mixture of 60% He and 40% Ar. For the elongation after fracture the best values, about 36%, were obtained for pure gases. As a main conclusion, we can say that arc welding of copper is possible without loosing the mechanical and metallurgical properties of base metal. 6 refs

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.

Recovery of metal values from copper slag and reuse of residual secondary slag.

Science.gov (United States)

Sarfo, Prince; Das, Avimanyu; Wyss, Gary; Young, Courtney

2017-12-01

Resource and environmental factors have become major forces in mining and metallurgy sectors driving research for sustainability purposes. The concept of zero-waste processing has been gaining ground readily. The scant availability of high quality raw materials has forced the researchers to shift their focus to recycling while the exceedingly stringent environmental regulations have forced researchers to explore new frontiers of minimizing/eliminating waste generation. The present work is aimed at addressing both aspects by employing recycling to generate wealth from copper slag and producing utilizable materials at the same time thus restoring the ecosystem. Copper slag was characterized and processed. The pyro-metallurgical processing prospects to generate utilizable materials were arrived at through rigorous thermodynamic analysis. Carbothermal reduction at elevated temperature (near 1440°C) helped recover a majority of the metal values (e.g., Fe, Cu and Mo) into the iron-rich alloy product which can be a feed material for steel making. On the other hand, the non-metallic residue, the secondary slag, can be used in the glass and ceramic industries. Reduction time and temperature and carbon content were shown to be the most important process variables for the reaction which were optimized to identify the most favored operating regime that maximizes the metal recovery and simultaneously maximizes the hardness of the secondary slag and minimizes its density, the two major criteria for the secondary slag product to be utilizable. The flux addition level was shown to have relatively less impact on the process performance if these are maintained at an adequate level. The work established that the copper slag, a waste material, can be successfully processed to generate reusable products through pyrometallurgical processing. Copyright © 2017 Elsevier Ltd. All rights reserved.

Corrosion induced clogging and plugging in water-cooled generator cooling circuit

International Nuclear Information System (INIS)

Park, B.G.; Hwang, I.S.; Rhee, I.H.; Kim, K.T.; Chung, H.S.

2002-01-01

Water-cooled electrical generators have been experienced corrosion-related problems that are restriction of flow through water strainers caused by collection of excessive amounts of copper corrosion products (''clogging''), and restriction of flow through the copper strands in the stator bars caused by growth or deposition of corrosion products on the walls of the hollow strands (''plugging''). These phenomena result in unscheduled shutdowns that would be a major concern because of the associated loss in generating capacity. Water-cooled generators are operated in one of two modes. They are cooled either with aerated water (dissolved oxygen >2 ppm) or with deaerated water (dissolved oxygen <50 ppb). Both modes maintain corrosion rates at satisfactorily low levels as long as the correct oxygen concentrations are maintained. However, it is generally believed that very much higher copper corrosion rates result at the intermediate oxygen concentrations of 100-1000 ppb. Clogging and plugging are thought to be associated with these intermediate concentrations, and many operators have suggested that the period of change from high-to-low or from low-to-high oxygen concentration is particularly damaging. In order to understand the detailed mechanism(s) of the copper oxide formation, release and deposition and to identify susceptible conditions in the domain of operating variables, a large-scale experiments are conducted using six hollow strands of full length connected with physico-chemically scaled generator cooling water circuit. To ensure a close simulation of thermal-hydraulic conditions in a generator stator, strands of the loop will be ohmically heated using AC power supply. Experiments is conducted to cover oxygen excursions in both high dissolved oxygen and low dissolved oxygen conditions that correspond to two representative operating condition at fields. A thermal upset condition is also simulated to examine the impact of thermal stress. During experiments

Hydrogen-induced strain localisation in oxygen-free copper in the initial stage of plastic deformation

Science.gov (United States)

Yagodzinskyy, Yuriy; Malitckii, Evgenii; Tuomisto, Filip; Hänninen, Hannu

2018-03-01

Single crystals of oxygen-free copper oriented to easy glide of dislocations were tensile tested in order to study the hydrogen effects on the strain localisation in the form of slip bands appearing on the polished specimen surface under tensile straining. It was found that hydrogen increases the plastic flow stress in Stage I of deformation. The dislocation slip localisation in the form of slip bands was observed and analysed using an online optical monitoring system and atomic force microscopy. The fine structure of the slip bands observed with AFM shows that they consist of a number of dislocation slip offsets which spacing in the presence of hydrogen is markedly reduced as compared to that in the hydrogen-free specimens. The tensile tests and AFM observations were accompanied with positron annihilation lifetime measurements showing that straining of pure copper in the presence of hydrogen results in free volume generation in the form of vacancy complexes. Hydrogen-enhanced free-volume generation is discussed in terms of hydrogen interactions with edge dislocation dipoles forming in double cross-slip of screw dislocations in the initial stage of plastic deformation of pure copper.

Experimental investigation of powerful pulse current generators based on capacitive storage and explosive magnetic generators

Science.gov (United States)

Shurupov, A. V.; Zavalova, V. E.; Kozlov, A. V.; Shurupov, M. A.; Povareshkin, M. N.; Kozlov, A. A.; Shurupova, N. P.

2018-01-01

Experimental models of microsecond duration powerful generators of current pulses on the basis of explosive magnetic generators and voltage impulse generator have been developed for the electromagnetic pulse effects on energy facilities to verify their stability. Exacerbation of voltage pulse carried out through the use of electro explosive current interrupter made of copper wires with diameters of 80 and 120 μm. Experimental results of these models investigation are represented. Voltage fronts about 100 ns and the electric field strength of 800 kV/m are registered.

Hydrothermal growth of cross-linked hyperbranched copper dendrites using copper oxalate complex

Science.gov (United States)

Truong, Quang Duc; Kakihana, Masato

2012-06-01

A facile and surfactant-free approach has been developed for the synthesis of cross-linked hyperbranched copper dendrites using copper oxalate complex as a precursor and oxalic acid as a reducing and structure-directing agent. The synthesized particles are composed of highly branched nanostructures with unusual cross-linked hierarchical networks. The formation of copper dendrites can be explained in view of both diffusion control and aggregation-based growth model accompanied by the chelation-assisted assembly. Oxalic acid was found to play dual roles as reducing and structure-directing agent based on the investigation results. The understanding on the crystal growth and the roles of oxalic acid provides clear insight into the formation mechanism of hyperbranched metal dendrites.

Rapid Separation of Copper Phase and Iron-Rich Phase From Copper Slag at Low Temperature in a Super-Gravity Field

Science.gov (United States)

Lan, Xi; Gao, Jintao; Huang, Zili; Guo, Zhancheng

2018-06-01

A novel approach for quickly separating a metal copper phase and iron-rich phase from copper slag at low temperature is proposed based on a super-gravity method. The morphology and mineral evolution of the copper slag with increasing temperature were studied using in situ high-temperature confocal laser scanning microscopy and ex situ scanning electron microscopy and X-ray diffraction methods. Fe3O4 particles dispersed among the copper slag were transformed into FeO by adding an appropriate amount of carbon as a reducing agent, forming the slag melt with SiO2 at low temperature and assisting separation of the copper phase from the slag. Consequently, in a super-gravity field, the metallic copper and copper matte were concentrated as the copper phase along the super-gravity direction, whereas the iron-rich slag migrated in the opposite direction and was quickly separated from the copper phase. Increasing the gravity coefficient (G) significantly enhanced the separation efficiency. After super-gravity separation at G = 1000 and 1473 K (1200 °C) for 3 minutes, the mass fraction of Cu in the separated copper phase reached 86.11 wt pct, while that in the separated iron-rich phase was reduced to 0.105 wt pct. The recovery ratio of Cu in the copper phase was as high as up to 97.47 pct.

Transcriptome response to copper heavy metal stress in hard-shelled mussel (Mytilus coruscus

Directory of Open Access Journals (Sweden)

Meiying Xu

2016-03-01

Full Text Available The hard-shelled mussel (Mytilus coruscus has considerably one of the most economically important marine shellfish worldwide and considered as a good invertebrate model for ecotoxicity study for a long time. In the present study, we used Illumina sequencing technology (HiSeq2000 to sequence, assemble and annotate the transcriptome of the hard-shelled mussel which challenged with copper pollution. A total of 21,723,913 paired-end clean reads (NCBI SRA database SRX1411195 were generated from HiSeq2000 sequencer and 96,403 contigs (with N50 = 1118 bp were obtained after de novo assembling with Trinity software. Digital gene expression analysis reveals 1156 unigenes are upregulated and 1681 unigenes are downregulated when challenged with copper. By KEGG pathway enrichment analysis, we found that unigenes in four KEGG pathways (aminoacyl-tRNA biosynthesis, apoptosis, DNA replication and mismatch repair show significant differential expressed between control and copper treated groups. We hope that the gill transcriptome in copper treated hard-shelled mussel can give useful information to understand how mussel handles with heavy metal stress at molecular level. Keywords: Hard-shelled mussel, Heavy metal, Transcriptome, Ecotoxicity

FDX: a fast discharge homopolar generator

International Nuclear Information System (INIS)

Weldon, W.F.; Rylander, H.G.; Woodson, H.H.

1977-01-01

A study was undertaken to determine the fundamental limitations to the discharge times of homopolar generators. As a result of the study, a Fast Discharge Experiment (FDX) was proposed. FDX is a small (365 kJ), counterrotating disk type homopolar generator designed to explore the limits to homopolar generator discharge times. The FDX rotors are forged aluminum alloy with flame sprayed copper slip rings. Solid copper graphite brushes are used with a 95% packing factor on the slip rings. The high magnetic field required for fast discharge (3.6 T average) is provided by discharging the CEM 5.0 MJ homopolar generator into a four-turn, graphite-reinforced, room temperature copper coil. Since the field is pulsed and FDX rotors cannot be self motored, they are brought up to speed with two 37 kW air turbines. The two aluminum rotors are 30 cm in diameter and of a rimmed, modified constant stress configuration. They are designed for a maximum operating speed of 28,000 r/min at which point they each store 182.5 kJ and develop 104 V. The aluminum discharge coax is approximately 38 cm in diameter and is designed to carry the 1.88 MA anticipated from a half speed (14,000 r/min) short circuit discharge which would stop the rotors in 1.0 ms. It is predicted that the machine will ring on its own internal impedance for approximately five cycles in this mode. The discharge coax is shorted by four very fast making switches. Additional impedance can be introduced into the discharge circuit by extending the switch coaxes to allow full speed 1.4 MA discharges in approximately 3.5 ms

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

Specification of steam generator, condenser and regenerative heat exchanger materials for nuclear applications

International Nuclear Information System (INIS)

Jovasevic, J.V.; Stefanovic, V.M.; Spasic, Z.LJ.

1977-01-01

The basic standards specifications of materials for nuclear applications are selected. Seamless Ni-Cr-Fe alloy Tubes (Inconel-600) for steam generators, condensers and other heat exchangers can be employed instead of austenitic stainless steal or copper alloys tubes; supplementary requirements for these materials are given. Specifications of Ni-Cr-Fe alloy plate, sheet and strip for steam generator lower sub-assembly, U-bend seamless copper-alloy tubes for heat exchanger and condensers are also presented. At the end, steam generator channel head material is proposed in the specification for carbon-steel castings suitable for welding

Atmospheric pollution with copper around the copper mine and flotation, 'Buchim', Republic of Macedonia, using biomonitoring moss and lichen technique

International Nuclear Information System (INIS)

Balabanova, Biljana; Bacheva, Katerina; Shajn, Robert; Stafilov, Trajche

2009-01-01

This paper has studied the atmospheric pollution with copper due to copper mining and flotation 'Buchim' near Radovish, Republic of Macedonia. The copper ore and ore tailings continually are exposed to open air, which occur winds carry out the fine particles in to atmosphere. Moss (Hyloconium splendens and Pleurozium schrebery) and lichen (Hypogymnia physodes and Parmelia sulcata) samples were used for biomonitoring the possible atmospheric pollution with copper in the mine vicinity. Moss and lichen samples were digested by using of microwave digestion system and copper was analyzed by atomic emission spectrometry with inductively coupled plasma (ICPAES). The obtained values for the content of copper in moss and lichen samples were statistically processed using the nonparametric and parametric analysis. Maps of areal deposition of copper show an increase content of copper in the vicinity of mine, but long distance distribution of this element is not established yet.

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).

Dissolution of copper and iron from malachite ore and precipitation of copper sulfate pentahydrate by chemical process

OpenAIRE

H. Kokes; M.H. Morcali; E. Acma

2014-01-01

The present work describes an investigation of a chemical process for the recovery of copper and iron from malachite ore. For the dissolution of copper and iron, H2SO4 was employed as well as H2O2 as an oxidizing agent. The effects of reaction temperature and time, acid concentration, liquid-to-solid ratio and agitation rate on the copper and iron percentage were investigated. Following the steps of dissolving the copper and iron sulfate and filtering, iron (III) hydroxide was precipitated by...

Rate and Regulation of Copper Transport by Human Copper Transporter 1 (hCTR1)*

Science.gov (United States)

Maryon, Edward B.; Molloy, Shannon A.; Ivy, Kristin; Yu, Huijun; Kaplan, Jack H.

2013-01-01

Human copper transporter 1 (hCTR1) is a homotrimer of a 190-amino acid monomer having three transmembrane domains believed to form a pore for copper permeation through the plasma membrane. The hCTR1-mediated copper transport mechanism is not well understood, nor has any measurement been made of the rate at which copper ions are transported by hCTR1. In this study, we estimated the rate of copper transport by the hCTR1 trimer in cultured cells using 64Cu uptake assays and quantification of plasma membrane hCTR1. For endogenous hCTR1, we estimated a turnover number of about 10 ions/trimer/s. When overexpressed in HEK293 cells, a second transmembrane domain mutant of hCTR1 (H139R) had a 3-fold higher Km value and a 4-fold higher turnover number than WT. Truncations of the intracellular C-terminal tail and an AAA substitution of the putative metal-binding HCH C-terminal tripeptide (thought to be required for transport) also exhibited elevated transport rates and Km values when compared with WT hCTR1. Unlike WT hCTR1, H139R and the C-terminal mutants did not undergo regulatory endocytosis in elevated copper. hCTR1 mutants combining methionine substitutions that block transport (M150L,M154L) on the extracellular side of the pore and the high transport H139R or AAA intracellular side mutations exhibited the blocked transport of M150L,M154L, confirming that Cu+ first interacts with the methionines during permeation. Our results show that hCTR1 elements on the intracellular side of the hCTR1 pore, including the carboxyl tail, are not essential for permeation, but serve to regulate the rate of copper entry. PMID:23658018

21 CFR 73.2647 - Copper powder.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Copper powder. 73.2647 Section 73.2647 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2647 Copper powder. (a) Identity and specifications. The color additive copper powder shall conform in identity and specifications to the requirements of § 73...

The Menkes and Wilson disease genes counteract in copper toxicosis in Labrador retrievers: a new canine model for copper-metabolism disorders

Directory of Open Access Journals (Sweden)

Hille Fieten

2016-01-01

Full Text Available The deleterious effects of a disrupted copper metabolism are illustrated by hereditary diseases caused by mutations in the genes coding for the copper transporters ATP7A and ATP7B. Menkes disease, involving ATP7A, is a fatal neurodegenerative disorder of copper deficiency. Mutations in ATP7B lead to Wilson disease, which is characterized by a predominantly hepatic copper accumulation. The low incidence and the phenotypic variability of human copper toxicosis hamper identification of causal genes or modifier genes involved in the disease pathogenesis. The Labrador retriever was recently characterized as a new canine model for copper toxicosis. Purebred dogs have reduced genetic variability, which facilitates identification of genes involved in complex heritable traits that might influence phenotype in both humans and dogs. We performed a genome-wide association study in 235 Labrador retrievers and identified two chromosome regions containing ATP7A and ATP7B that were associated with variation in hepatic copper levels. DNA sequence analysis identified missense mutations in each gene. The amino acid substitution ATP7B:p.Arg1453Gln was associated with copper accumulation, whereas the amino acid substitution ATP7A:p.Thr327Ile partly protected against copper accumulation. Confocal microscopy indicated that aberrant copper metabolism upon expression of the ATP7B variant occurred because of mis-localization of the protein in the endoplasmic reticulum. Dermal fibroblasts derived from ATP7A:p.Thr327Ile dogs showed copper accumulation and delayed excretion. We identified the Labrador retriever as the first natural, non-rodent model for ATP7B-associated copper toxicosis. Attenuation of copper accumulation by the ATP7A mutation sheds an interesting light on the interplay of copper transporters in body copper homeostasis and warrants a thorough investigation of ATP7A as a modifier gene in copper-metabolism disorders. The identification of two new functional

Thermophysical properties and microstructure of graphite flake/copper composites processed by electroless copper coating

International Nuclear Information System (INIS)

Liu, Qian; He, Xin-Bo; Ren, Shu-Bin; Zhang, Chen; Ting-Ting, Liu; Qu, Xuan-Hui

2014-01-01

Highlights: • GF–copper composites were fabricated using a sparking plasma sintering, which involves coating GF with copper, using electroless plating technique. • The oriented graphite flake distributed homogeneously in matrix. • With the increase of flake graphite from 44 to 71 vol.%, the basal plane thermal conductivity of composites increases from 445 to 565 W m −1 K −1 and the thermal expansion of composites decreases from 8.1 to 5.0. • The obtained composites are suitable for electronic packaging materials. -- Abstract: This study focuses on the fabrication of thermal management material for power electronics applications using graphite flake reinforced copper composites. The manufacturing route involved electroless plating of copper on the graphite flake and further spark plasma sintering of composite powders. The relative density of the composites with 44–71 vol.% flakes achieved up to 98%. Measured thermal conductivities and coefficients of thermal expansion of composites ranged from 455–565 W m −1 K −1 and 8 to 5 ppm K −1 , respectively. Obtained graphite flake–copper composites exhibit excellent thermophysical properties to meet the heat dispersion and matching requirements of power electronic devices to the packaging materials

Studies on the copper-poisoned soils. Part 2. Actual condition of the copper-poison in the soils and the rice plants

Energy Technology Data Exchange (ETDEWEB)

Koshiba, N.; Sano, Y.

1968-01-01

Copper contents of soils and rice plants in paddylands were correlated with growth. The results were as follows: available copper content in paddies was 181.8 ppm where the rice plants grew poorly, and was more than 4 times the value of the soil where rice plants grew favorably. The difference growth was obviously caused by available copper. The copper content of the rice plants showing poor growth was the same as those which grew well. Plants were poisoned by available copper of more than 100 ppm. The available copper contents were increased by drying processes of the paddyland soils distributed in the copper-poisoned area. 8 references, 6 tables.

CopM is a novel copper-binding protein involved in copper resistance in Synechocystis sp. PCC 6803

Science.gov (United States)

Giner-Lamia, Joaquín; López-Maury, Luis; Florencio, Francisco J

2015-01-01

Copper resistance system in the cyanobacterium Synechocystis sp. PCC 6803 comprises two operons, copMRS and copBAC, which are expressed in response to copper in the media. copBAC codes for a heavy-metal efflux–resistance nodulation and division (HME-RND) system, while copMRS codes for a protein of unknown function, CopM, and a two-component system CopRS, which controls the expression of these two operons. Here, we report that CopM is a periplasmic protein able to bind Cu(I) with high affinity (KD ∼3 × 10−16). Mutants lacking copM showed a sensitive copper phenotype similar to mutants affected in copB, but lower than mutants of the two-component system CopRS, suggesting that CopBAC and CopM constitute two independent resistance mechanisms. Moreover, constitutive expression of copM is able to partially suppress the copper sensitivity of the copR mutant strain, pointing out that CopM per se is able to confer copper resistance. Furthermore, constitutive expression of copM was able to reduce total cellular copper content of the copR mutant to the levels determined in the wild-type (WT) strain. Finally, CopM was localized not only in the periplasm but also in the extracellular space, suggesting that CopM can also prevent copper accumulation probably by direct copper binding outside the cell. PMID:25545960

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

Copper hexacyanoferrate formation on the modified silica surface with DAB-Am-16 dendrimer

International Nuclear Information System (INIS)

Carmo, Devaney R. do; Gabriel Junior, Suelino; Bicalho, Urquisa O.; Paim, Leonardo L.

2009-01-01

The dendrimer hexadecamine poly(propylene)imine (DAB-Am-16) of third generation (G-3) was anchored on the silica gel surface. The modified silica interact easily with Cu 2+ and then with hexacyanoferrate to form copper hexacyanoferrate. The modified silica was characterized by following techniques: nuclear magnetic resonance (NMR), infrared (FTIR), energy dispersive X-ray (EDX) and cyclic voltammetry. As application of the composite obtained, the modified silica containing copper hexacyanoferrate (CuHCFSD) was tested for a voltammetric determination of nitrite using a graphite paste modified electrode. The modified graphite paste electrode can be applied also to the determination of others biological substances with success. (author)

Copper sulphate poisoning in horses

Energy Technology Data Exchange (ETDEWEB)

Bauer, M

1975-01-01

In the archives of the Clinic for Internal Diseases of Domestic Animals at the Veterinary Faculty of Zagreb University some thirty cases of horse disease diagnosed as copper sulphate poisoning were noted. The data correspond in many respects to the clinical findings of copper sulphate poisoning in other domestic animals. A series of experimental horse poisonings were undertaken in order to determine the toxicity of copper sulphate. The research results are as follows: Horses are sensitive to copper sulphate. Even a single application of 0.125 g/kg body weight in 1% concentration by means of incubation into the stomach causes stomach and gut disturbances and other poisoning symptoms. Poisoning occurs in two types: acute and chronic. The former appears after one to three applications of copper sulphate solution and is characterized by gastroenteritis, haemolysis, jaundice and haemoglobinuria with signs of consecutive damage of kidney, liver and other organs. The disease, from the first application to death lasts for two weeks. Chronic poisoning is caused by ingestion of dry copper sulphate in food (1% solution dried on hay or clover) for two or more months. There are chronic disturbances of stomach and gut and loss of weight, and consecutive (three to four) haemolytic crises similar to those of acute poisoning. From the beginning of poisoning to death six or more months can elapse.

The effect of primary copper slag cooling rate on the copper valorization in the flotation process

Directory of Open Access Journals (Sweden)

Aleksandar Mihajlović

2015-06-01

Full Text Available Technological procedure of slow cooling slag from primary copper production is applied in the purpose of copper recovery in the level of 98.5% to blister. This technological procedure is divided into two phases, first slow cooling of slag on the air for 24 hours, and then accelerated cooling with water for 48 hours. Within the research following methods were used: calculation of nonstationary slag cooling, verification of the calculation using computer simulation of slag cooling in the software package COMSOL Multiphysics and experimental verification of simulation results. After testing of the experimentally gained samples of slowly cooled slag it was found that this technological procedure gives the best results in promoting growth or coagulation of dispersed particles of copper sulfide and copper in the slag, thereby increasing the utilization of the flotation process with a decrease of copper losses through very fine particles.

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

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Weiqi Leng

2017-06-01

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

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

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Rudnik E.

2016-06-01

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

Electrochemical remediation of copper contaminated clay soils

Energy Technology Data Exchange (ETDEWEB)

Korolev, V.A.; Babakina, O.A.; Mitojan, R.A. [Moscow State Univ. (Russian Federation)

2001-07-01

The study objective focused on electrochemical remediation copper polluted soils in the presence of adjuvant substances and conditions that are more effective for the treatment. Some of these substances were studied in different researches. Moreover, authors obtained a result of extraction copper rate higher than 90%. In this connection the following problems were set: - Influence organic and inorganic substances on copper mobility in soil under the DC current. - Moisture effect on copper migration in clay. - Electrochemical remediation soils different mineralogical composition. - A washing conditions contribution to electrochemical remediation of soil from copper. - Accuracy rating experimental dates. (orig.)

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

Effectiveness acidic pre-cleaning for copper-gold ore

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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.

Copper tolerance in Becium homblei

Energy Technology Data Exchange (ETDEWEB)

Reilly, C; Stone, J

1971-04-09

Analyses show that Becium homblei has apparently no mechanism for limiting copper uptake. As growth proceeds, the concentration of metal increases in leaves and stems. Much of the copper is bound to structural material of the cells. There is a significant difference between the amount of extractable material in root and leaf tissues. These differences, in conjunction with the extrinsic factor of regular bush fires, were important factors in the evolution of this copper-resistant species of Becium. 9 references.

Grape berry bacterial inhibition by different copper fungicides

Directory of Open Access Journals (Sweden)

Martins Guilherme

2016-01-01

Full Text Available Copper fungicides are widely used in viticulture. Due to its large spectrum of action, copper provides an efficient control over a great number of vine pathogens. Previous studies showed that, high levels of cupric residues can impact grape-berry microbiota, in terms of the size and population structure, reducing the diversity and the abundance. Due to the importance of grape-berry bacterial in crop health, and the potential impact of copper fungicides over the microbiota, we determined Minimum Inhibitory Concentration (MIC of different copper formulations for bacterial species isolated from grape berries. We study the Minimum Inhibitory Concentration (MIC of different copper formulations (copper sulphate (CuSO4 pure, Bordeaux mixture (CuSO4 + Ca(OH2, copper oxide (Cu2O, copper hydroxide (Cu(OH2 over 92 bacterial strains isolated from grape berries in different stages of the ripening process. The results of MIC measurements revealed that the different copper formulations have a variable inhibitory effect and among the different isolates, some species are the most resistant to all copper formulations than others. This study confirm that usage of cupric phytosanitary products should be reasonable independently of the farming system; they also provide evidence of the importance of the choice of which copper formulations are to be used regarding their impact on the grape berry bacterial microbiota.

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.

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

Science.gov (United States)

Chen, Guangcun; Lin, Huirong; Chen, Xincai

2016-12-28

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

Seasonal and spatial patterns of metals at a restored copper mine site. I. Stream copper and zinc

International Nuclear Information System (INIS)

Bambic, Dustin G.; Alpers, Charles N.; Green, Peter G.; Fanelli, Eileen; Silk, Wendy K.

2006-01-01

Seasonal and spatial variations in metal concentrations and pH were found in a stream at a restored copper mine site located near a massive sulfide deposit in the Foothill copper-zinc belt of the Sierra Nevada, California. At the mouth of the stream, copper concentrations increased and pH decreased with increased streamflow after the onset of winter rain and, unexpectedly, reached extreme values 1 or 2 months after peaks in the seasonal hydrographs. In contrast, aqueous zinc and sulfate concentrations were highest during low-flow periods. Spatial variation was assessed in 400 m of reach encompassing an acidic, metal-laden seep. At this seep, pH remained low (2-3) throughout the year, and copper concentrations were highest. In contrast, the zinc concentrations increased with downstream distance. These spatial patterns were caused by immobilization of copper by hydrous ferric oxides in benthic sediments, coupled with increasing downstream supply of zinc from groundwater seepage. - Seasonal hydrology and benthic sediments control copper and zinc concentrations in a stream through a restored mine site

Oxidation-assisted graphene heteroepitaxy on copper foil

OpenAIRE

Reckinger, Nicolas; Tang, Xiaohui; Joucken, Frédéric; Lajaunie, Luc; Arenal, Raul; Dubois, Emmanuel; Hackens, Benoît; Henrard, Luc; Colomer, Jean-François

2016-01-01

We propose an innovative, easy-to-implement approach to synthesize large-area singlecrystalline graphene sheets by chemical vapor deposition on copper foil. This method doubly takes advantage of residual oxygen present in the gas phase. First, by slightly oxidizing the copper surface, we induce grain boundary pinning in copper and, in consequence, the freezing of the thermal recrystallization process. Subsequent reduction of copper under hydrogen suddenly unlocks the delayed reconstruction, f...

Printed circuit board recycling: Physical processing and copper extraction by selective leaching.

Science.gov (United States)

Silvas, Flávia P C; Correa, Mónica M Jiménez; Caldas, Marcos P K; de Moraes, Viviane T; Espinosa, Denise C R; Tenório, Jorge A S

2015-12-01

Global generation of waste electrical and electronic equipment (WEEE) is about 40 million tons per year. Constant increase in WEEE generation added to international legislations has improved the development of processes for materials recovery and sustainability of electrical and electronic industry. This paper describes a new hydrometallurgical route (leaching process) to recycle printed circuit boards (PCBs) from printers to recover copper. Methodology included PCBs characterization and a combined route of physical and hydrometallurgical processing. Magnetic separation, acid digestion and chemical analysis by ICP-OES were performed. On leaching process were used two stages: the first one in a sulfuric media and the second in an oxidant media. The results showed that the PCBs composition was 74.6 wt.% of non-magnetic material and 25.4 wt.% of magnetic one. The metallic fraction corresponded to 44.0 wt.%, the polymeric to 28.5 wt.% and the ceramic to 27.5 wt.%. The main metal was copper and its initial content was 32.5 wt.%. On sulfuric leaching 90 wt.% of Al, 40 wt.% of Zn and 8.6 wt.% of Sn were extracted, whereas on oxidant leaching tests the extraction percentage of Cu was 100 wt.%, of Zn 60 wt.% and of Al 10 wt.%. At the end of the hydrometallurgical processing was obtained 100% of copper extraction and the recovery factor was 98.46%, which corresponds to a 32 kg of Cu in 100 kg of PCB. Copyright © 2015 Elsevier Ltd. All rights reserved.

Uranium accompanying recovery from copper ores

International Nuclear Information System (INIS)

Golynko, Z.Sh.; Laskorin, B.N.

1981-01-01

In the search for new raw material sources for nuclear power engineering a review of the technique of uranium accompaning recovery from copper ores reprocessing products in some countries is presented. In the USA a sorption method of uranium extraction by means of strongly basic ion exchange resins from solutions upon copper case- hardening with subsequent extraction from eluates by solutions of tertiary amines is realized. Elution is realized with sulphuric acid. In South Africa an extraction reprocessing of gravitational concentrate extracted from copper sulphide flotation tailings is organized. In India the uranium extraction from copper ores flotation enrichment tailings is organized on a commerical scale. Presented are data on the scale of uranium recovery, various conditions of its recovery as well as block diagrams of the processes. It is shown that copper ores become an additional source of uranium recovery [ru

Role of oxygen-containing functional groups in forest fire-generated and pyrolytic chars for immobilization of copper and nickel.

Science.gov (United States)

Esfandbod, Maryam; Merritt, Christopher R; Rashti, Mehran Rezaei; Singh, Balwant; Boyd, Sue E; Srivastava, Prashant; Brown, Christopher L; Butler, Orpheus M; Kookana, Rai S; Chen, Chengrong

2017-01-01

Char as a carbon-rich material, can be produced under pyrolytic conditions, wildfires or prescribed burn offs for fire management. The objective of this study was to elucidate mechanistic interactions of copper (Cu 2+ ) and nickel (Ni 2+ ) with different chars produced by pyrolysis (green waste, GW; blue-Mallee, BM) and forest fires (fresh-burnt by prescribed fire, FC; aged char produced by wild fire, AC). The pyrolytic chars were more effective sorbents of Cu 2+ (∼11 times) and Ni 2+ (∼5 times) compared with the forest fire chars. Both cross-polarization (CPMAS-NMR) and Bloch decay (BDMAS-NMR) 13 C NMR spectroscopies showed that forest fire chars have higher woody components (aromatic functional groups) and lower polar groups (e.g. O-alkyl C) compared with the pyrolytic chars. The polarity index was greater in the pyrolytic chars (0.99-1.34) than in the fire-generated chars (0.98-1.15), while aromaticity was lower in the former than in the latter. Fourier transform infrared (FTIR) and Raman spectroscopies indicated the binding of carbonate and phosphate with both Cu 2+ and Ni 2+ in all chars, but with a greater extent in pyrolytic than forest fire-generated chars. These findings have demonstrated the key role of char's oxygen-containing functional groups in determining their sorption capacity for the Cu 2+ and Ni 2+ in contaminated lands. Copyright © 2016 Elsevier Ltd. All rights reserved.

Influence of copper volume fraction on tensile strain/stress tolerances of critical current in a copper-plated DyBCO-coated conductor

International Nuclear Information System (INIS)

Ochiai, Shojiro; Okuda, Hiroshi; Arai, Takahiro; Sugano, Michinaka; Osamura, Kozo; Prusseit, Werner

2013-01-01

The influence of the volume fraction (V f ) of copper, plated at room temperature over a DyBa 2 Cu 3 O 7-δ -coated conductor, on the tensile strain tolerance and stress tolerance of critical current at 77 K was studied over a wide range of copper V f values. The copper plating exerts a tensile stress during cooling because copper has a higher coefficient of thermal expansion than the substrate conductor. Before application of tensile strain, the copper plated at room temperature yielded at 77 K when the copper V f was lower than a critical value, and was in an elastic state at 77 K when the copper V f was higher than the critical value. The strain tolerance of critical current increased with increasing copper V f due to an increase in thermally induced compressive strain in the substrate tape. The stress tolerance of critical current decreased with increasing copper V f because copper is softer than the substrate tape. These results, together with the trade-off between strain tolerance and stress tolerance (i.e., stress tolerance decreases with increasing strain tolerance), were analyzed by modeling. The results show that the restriction imposed by the trade-off, which limits the ability to simultaneously obtain a high strain tolerance and a high stress tolerance, can be relaxed by strengthening the copper. (author)

Tin-silver and tin-copper alloys for capillarity joining-soft soldering-of copper piping

International Nuclear Information System (INIS)

Duran, J.; Amo, J. M.; Duran, C. M.

2001-01-01

It is studied the influence of the type of alloy used as filling material on the defects of the soldering joints in copper piping installations, which induce the fluid leak of the systems. The different eutectic temperatures and solidus-liquidus ranges of these alloys, require the setting of the soldering heat input in each case to obtain the suitable capillarity features and alloying temperatures to achieve for the correct formation of the bonding. Most defects in the joints are demonstrated to be generated by bad dossification of thermal inputs, which led depending on the filler alloy used to variations in its fluidity that may produce penetration failures in the bonds or insufficient consistency for the filling of the joints. (Author) 7 refs

In long-term bedridden elderly patients with dietary copper deficiency, biochemical markers of bone resorption are increased with copper supplementation during 12 weeks.

Science.gov (United States)

Kawada, Etsuo; Moridaira, Kazuaki; Itoh, Katsuhiko; Hoshino, Ayami; Tamura, Jun'ichi; Morita, Toyoho

2006-01-01

Although the effect of copper on bone has been tested in animals and healthy subjects, no studies concerning the effect of copper supplementation on bone metabolism in patients with copper deficiency have been reported because of the rarity of these patients. This study was conducted to investigate the effect of copper supplementation on bone metabolism in copper-deficient patients. This study included 10 patients (83.7 +/- 8.3 years) with dietary copper deficiency under long-term bed rest for more than 12 months. They had their diets supplemented with copper sulfate (3 mg/day) over 12 weeks in addition to their diet of only one kind of enteral food with a low concentration of copper. Serum copper and ceruloplasmin, urinary deoxypyridinoline (DPD) and collagen-type 1 N-telopeptide (NTX) (biomarkers of bone resorption), serum osteocalcin (OC) and bone-specific alkaline phosphatase (Bone ALP) (biomarkers of bone formation) were analyzed at baseline, 4 and 12 weeks after copper supplementation. DPD and NTX excretion were significantly increased 4 weeks after copper supplementation (p = 0.009 and p = 0.013, respectively). Serum bone ALP and OC were not significantly changed 12 weeks after copper supplementation (p = 0.051 and p = 0.594). In patients with nutritional copper deficiency, bone resorption markers are increased with copper supplementation. Copyright (c) 2006 S. Karger AG, Basel.

Synthesis of Commercial Products from Copper Wire-Drawing Waste

Science.gov (United States)

Ayala, J.; Fernández, B.

2014-06-01

Copper powder and copper sulfate pentahydrate were obtained from copper wire-drawing scale. The hydrometallurgical recycling process proposed in this article yields a high-purity copper powder and analytical grade copper sulfate pentahydrate. In the first stage of this process, the copper is dissolved in sulfuric acid media via dismutation of the scale. In the second stage, copper sulfate pentahydrate is precipitated using ethanol. Effects such as pH, reaction times, stirring speed, initial copper concentration, and ethanol/solution volume ratio were studied during the precipitation from solution reaction. The proposed method is technically straightforward and provides efficient recovery of Cu from wire-drawing scale.

Hypoxia targeting copper complexes

International Nuclear Information System (INIS)

Dearling, J.L.

1998-11-01

The importance and incidence of tumour hypoxia, its measurement and current treatments available, including pharmacological and radiopharmacological methods of targeting hypoxia, are discussed. A variety of in vitro and in vivo methods for imposing hypoxia have been developed and are reviewed. Copper, its chemistry, biochemistry and radiochemistry, the potential for use of copper radionuclides and its use to date in this field is considered with particular reference to the thiosemicarbazones. Their biological activity, metal chelation, in vitro and in vivo studies of their radiocopper complexes and the potential for their use as hypoxia targeting radiopharmaceuticals is described. The reduction of the copper(II) complex to copper(l), its pivotal importance in their biological behaviour, and the potential for manipulation of this to effect hypoxia selectivity are described. An in vitro method for assessing the hypoxia selectivity of radiopharmaceuticals is reported. The rapid deoxygenation and high viability of a mammalian cell culture in this system is discussed and factors which may affect the cellular uptake of a radiopharmaceutical are described. The design, synthesis and complexation with copper and radiocopper of a range of bis(thiosemicarbazones) is reported. Synthesis of these compounds is simple giving high yields of pure products. The characteristics of the radiocopper complexes ( 64 Cu) including lipophilicity and redox activity are reported (reduction potentials in the range -0.314 - -0.590 V). High cellular uptakes of the radiocopper complexes of the ligands, in hypoxic and normoxic EMT6 and CHO320 cells, were observed. Extremes of selectivity are shown ranging from the hypoxia selective 64 Cu(II)ATSM to normoxic cell selective 64 Cu(II)GTS. The selectivities observed are compared with the physico chemical characteristics of the complexes. A good correlation exists between selectivity of the complex and its Cu(II)/Cu(I) reduction potential, with hypoxia

Optical Subsystems for Next Generation Access Networks

DEFF Research Database (Denmark)

Lazaro, J.A; Polo, V.; Schrenk, B.

2011-01-01

Recent optical technologies are providing higher flexibility to next generation access networks: on the one hand, providing progressive FTTx and specifically FTTH deployment, progressively shortening the copper access network; on the other hand, also opening fixed-mobile convergence solutions...... in next generation PON architectures. It is provided an overview of the optical subsystems developed for the implementation of the proposed NG-Access Networks....

Vacuolar H+ -ATPase c protects glial cell death induced by sodium nitroprusside under glutathione-depleted condition.

Science.gov (United States)

Byun, Yu Jeong; Lee, Seong-Beom; Lee, Hwa Ok; Son, Min Jeong; Kim, Ho-Shik; Kwon, Oh-Joo; Jeong, Seong-Whan

2011-08-01

We examined the role of the c subunit (ATP6L) of vacuolar H(+) -ATPase and its molecular mechanisms in glial cell death induced by sodium nitroprusside (SNP). ATP6L siRNA-transfected cells treated with SNP showed a significant increase in cytotoxicity under glutathione (GSH)-depleted conditions after pretreatment with buthionine sulfoximine, but reduction of ATP6L did not affect the regulation of lysosomal pH in analyses with lysosomal pH-dependent fluorescence probes. Photodegraded SNP and ferrous sulfate induced cytotoxicity with the same pattern as that of SNP, but SNAP and potassium cyanide did not show activity. Pretreatment of the transfected cells with deferoxamine (DFO) reduced ROS production and significantly inhibited the cytotoxicity, which indicates that primarily iron rather than nitric oxide or cyanide from SNP contributes to cell death. Involvement of apoptotic processes in the cells was not shown. Pretreatment with JNK or p38 chemical inhibitor significantly inhibited the cytotoxicity, and we also confirmed that the MAPKs were activated in the cells by immunoblot analysis. Significant increase of LC3-II conversion was observed in the cells, and the conversions were inhibited by cotransfection of the MAPK siRNAs and pretreatment with DFO. Introduction of Atg5 siRNA inhibited the cytotoxicity and inhibited the activation of MAPKs and the conversion of LC3. We finally confirmed autophagic cell death and involvement of MAPKs by observation of autophagic vacuoles via electron microscopy. These data suggest that ATP6L has a protective role against SNP-induced autophagic cell death via inhibition of JNK and p38 in GSH-depleted glial cells. Copyright © 2011 Wiley-Liss, Inc.

Method for providing uranium with a protective copper coating

Science.gov (United States)

Waldrop, Forrest B.; Jones, Edward

1981-01-01

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

Effects of sodium nitroprusside in the prevention of schizophrenia-like symptoms induced by ketamine – A translational double-blind study

Directory of Open Access Journals (Sweden)

Tatiana M. N. Rezende

Full Text Available Abstract Background: Recent evidence has shown improvements in schizophrenia symptoms after the infusion of sodium nitroprusside (SNP, a nitric oxide (NO donor. In the rat model of schizophrenia using ketamine injection, pretreatment with SNP seems to prevent behavioral changes associated with positive symptoms for up to one week. Objective: We investigated whether SNP would have preventative effects on psychogenic symptoms induced by ketamine in healthy subjects. Methods: Healthy subjects (N = 38 were assigned to distinct groups that received SNP in different doses (0.15, 0.25, and 0.5 mcg/kg/min. First, participants received an infusion of SNP or placebo over 75 minutes. After 10 minutes, they were injected for 1 minute with a bolus of 0.26 mg/kg of ketamine and a maintenance dose was started 5 minutes later, with 0.25 mg/kg/h of ketamine for 50 minutes. Results: Ketamine-induced psychopathological alterations induced were reduced by SNP, as assessed with the Brief Psychological Rating Scale. Scores in the objective subscale of the Clinician-Administered Dissociative States Scale were also lower in SNP sessions compared to placebo. SNP had protective effects against deterioration in facial emotion and identity recognition tasks induced by ketamine. Discussion: Our findings support the view that SNP has preventative properties against psychotic manifestations.

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...

Thermophysical properties and microstructure of graphite flake/copper composites processed by electroless copper coating

Energy Technology Data Exchange (ETDEWEB)

Liu, Qian; He, Xin-Bo; Ren, Shu-Bin; Zhang, Chen; Ting-Ting, Liu; Qu, Xuan-Hui, E-mail: quxh@ustb.edu.cn

2014-02-25

Highlights: • GF–copper composites were fabricated using a sparking plasma sintering, which involves coating GF with copper, using electroless plating technique. • The oriented graphite flake distributed homogeneously in matrix. • With the increase of flake graphite from 44 to 71 vol.%, the basal plane thermal conductivity of composites increases from 445 to 565 W m{sup −1} K{sup −1} and the thermal expansion of composites decreases from 8.1 to 5.0. • The obtained composites are suitable for electronic packaging materials. -- Abstract: This study focuses on the fabrication of thermal management material for power electronics applications using graphite flake reinforced copper composites. The manufacturing route involved electroless plating of copper on the graphite flake and further spark plasma sintering of composite powders. The relative density of the composites with 44–71 vol.% flakes achieved up to 98%. Measured thermal conductivities and coefficients of thermal expansion of composites ranged from 455–565 W m{sup −1} K{sup −1} and 8 to 5 ppm K{sup −1}, respectively. Obtained graphite flake–copper composites exhibit excellent thermophysical properties to meet the heat dispersion and matching requirements of power electronic devices to the packaging materials.

Copper : recession and recovery

International Nuclear Information System (INIS)

Warwick-Ching, T.

2002-01-01

In 2002, the world output for copper will fall for the first time in nearly a decade because of financial pressure and voluntary constraints. Cutbacks at copper mines amount to 760,000 tonnes per year. These cutbacks have occurred mostly in the United States which holds the largest share of high cost mines. This paper discussed recent developments in both copper supply and demand. The United States is unique as both a large consumer and producer of copper. At 1.35 million tonnes, US mine output in 2001 was at its lowest since 1987. The cutbacks in mining in general were described in this paper with particular reference to the huge loss of mining and metallurgical activity in the United States during a prolonged period of low prices in the mid 1980s. The author noted that this period was followed by an exceptional decade when much of the industry rebounded. Only 8 mines closed outright in the United States and a handful in Canada since the recession of the 1980s, but that is partly because mines got bigger and there are fewer small mines in North America. There are only 4 electrolytic refineries and 3 smelters still active in the entire United States, of which 2 are operating at a fraction of capacity. It was noted that only the buoyancy of China prevented a much bigger decline in copper demand on a global scale

Behavior of copper corrosion products in water loops of heat-exchange units

International Nuclear Information System (INIS)

Zarembo, V.I.; Kritskii, V.G.; Slobodov, A.A.; Puchkov, L.V.

1989-01-01

This communication is dedicated to an examination of copper corrosion products (CP) in the conditions of real aqueous-chemical regime (ACR) parameters. The deposition of these CP in steam-generating zones (up to 85% of their total amount) stimulate local types of corrosion. The solubility in Cu CP (Cu 2 O, CuO, Cu(OH) 2 )-water (H 2 O)-gas (H 2 , O 2 )-conditioning additives (HCl, KOH) systems was determined by computer modeling according to the minimum Gibbs energy criterion on the basis of selected and matched thermodynamic constants for various chemical forms of copper under standard conditions. As a result of the authors' calculations they obtained the solubilities in water of CuO, Cu 2 O and Cu(OH) 2 when changing the dosage of active gases from 0 to 10 -2 mole/kg of water, of acid or equal to that of saturated vapor of pure water. Thus, they were able to monitor the behavior of copper CP in conditions modeling those of real ACR in operating heat exchange units, including in conditions deviating from the standard

Ligand-Doped Copper Oxo-hydroxide Nanoparticles are Effective Antimicrobials

Science.gov (United States)

Bastos, Carlos A. P.; Faria, Nuno; Ivask, Angela; Bondarenko, Olesja M.; Kahru, Anne; Powell, Jonathan

2018-04-01

Bacterial resistance to antimicrobial therapies is an increasing clinical problem. This is as true for topical applications as it is for systemic therapy. Topically, copper ions may be effective and cheap antimicrobials that act through multiple pathways thereby limiting opportunities to bacteria for resistance. However, the chemistry of copper does not lend itself to facile formulations that will readily release copper ions at biologically compatible pHs. Here, we have developed nanoparticulate copper hydroxide adipate tartrate (CHAT) as a cheap, safe, and readily synthesised material that should enable antimicrobial copper ion release in an infected wound environment. First, we synthesised CHAT and showed that this had disperse aquated particle sizes of 2-5 nm and a mean zeta potential of - 40 mV. Next, when diluted into bacterial medium, CHAT demonstrated similar efficacy to copper chloride against Escherichia coli and Staphylococcus aureus, with dose-dependent activity occurring mostly around 12.5-50 mg/L of copper. Indeed, at these levels, CHAT very rapidly dissolved and, as confirmed by a bacterial copper biosensor, showed identical intracellular loading to copper ions derived from copper chloride. However, when formulated at 250 mg/L in a topically applied matrix, namely hydroxyethyl cellulose, the benefit of CHAT over copper chloride was apparent. The former yielded rapid sustained release of copper within the bactericidal range, but the copper chloride, which formed insoluble precipitates at such concentration and pH, achieved a maximum release of 10 ± 7 mg/L copper by 24 h. We provide a practical formulation for topical copper-based antimicrobial therapy. Further studies, especially in vivo, are merited.

Role of aminophylline in refractory heart failure: a comparison to the vasodilator sodium nitroprusside, the old and the new.

Science.gov (United States)

DiBianco, R; Rosenfeld, S P; Katz, R J; Simpson, A G; Fletcher, R D; Singh, S

1980-08-01

Aminophylline [(theophylline ethylene diamine (TED)] reportedly improved cardiac hemodynamics by lowering vascular resistances and increasing contractility. TED as used clinically has not been compared to the vasodilator sodium nitroprusside (NP). To assess the relative hemodynamic effects of these two commonly used agents, the following comparison was made. Ten patients with congestive cardiomyopathy in chronic refractory heart failure [New York Heart Association (NYHA) class IV] were studied. All patients demonstrated cardiomegaly by chest x ray and echocardiography (LVd = 6.3 +/- 0.7 cm) and markedly abnormal hemodynamics during baseline observations (see Table I). Hemodynamic measurements at baseline were compared after TED infusion (mean blood level = 16 +/- 12 micrograms/m/TED) and during intravenous NP. No significant changes in heart rate occurred during either therapeutic intervention; a fall in mean arterial pressure of 10 mmHg (p TED. Theophylline ethylene diamine demonstrated no detectable cardiac hemodynamic effects 60--90 min post infusion despite proven blood levels, whereas NP exhibited distinctly beneficial effects in this patient group. Previous studies demonstrating improved hemodynamics occurring with TED have been limited to the time of infusion or within the following 40 min, a time when TED blood levels are maximum and therefore closest to toxicity. The results of this study suggest that TED demonstrates no beneficial hemodynamic effects in refractory heart failure as early as 1 h after infusion despite blood levels in the therapeutic range.

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.

What is the Potential for More Copper Fabrication in Zambia?

OpenAIRE

World Bank

2011-01-01

The copper fabrication industry lies between: (1) the industry that produces copper (as a commodity metal from mined ores as well as from recycling), and (2) the users of copper in finished products such as electronic goods. Copper fabrication involves the manufacture of products such as copper wire, wire rod, low-voltage cable, and other copper based semi-manufactures. Copper is clearly a...

Copper intoxication in sheep

Energy Technology Data Exchange (ETDEWEB)

Gazaryan, V.S.; Sogoyan, I.S.; Agabalov, G.A.; Mesropyan, V.V.

1966-01-01

Of 950 sheep fed hay from a vineyard sprayed regularly with copper sulfate, 143 developed clinical copper poisoning and 103 died. The Cu content of the hay was 10.23 mg%, of the liver of dead sheep 17-52 mg%, and of the blood serum of affected sheep 0.86 mg%. The symptoms and the histological findings in kidneys and liver are described.

Testing the Underlying Chemical Principles of the Biotic Ligand Model (BLM) to Marine Copper Systems: Measuring Copper Speciation Using Fluorescence Quenching.

Science.gov (United States)

Tait, Tara N; McGeer, James C; Smith, D Scott

2018-01-01

Speciation of copper in marine systems strongly influences the ability of copper to cause toxicity. Natural organic matter (NOM) contains many binding sites which provides a protective effect on copper toxicity. The purpose of this study was to characterize copper binding with NOM using fluorescence quenching techniques. Fluorescence quenching of NOM with copper was performed on nine sea water samples. The resulting stability constants and binding capacities were consistent with literature values of marine NOM, showing strong binding with [Formula: see text] values from 7.64 to 10.2 and binding capacities ranging from 15 to 3110 nmol mg [Formula: see text] Free copper concentrations estimated at total dissolved copper concentrations corresponding to previously published rotifer effect concentrations, in the same nine samples, were statistically the same as the range of free copper calculated for the effect concentration in NOM-free artificial seawater. These data confirms the applicability of fluorescence spectroscopy techniques for NOM and copper speciation characterization in sea water and demonstrates that such measured speciation is consistent with the chemical principles underlying the biotic ligand model approach for bioavailability-based metals risk assessment.

Copper ion treatment for zebra mussel mitigation in house service water systems

Energy Technology Data Exchange (ETDEWEB)

Babinec, J. [We Energies, Milwaukee, WI (United States)

2003-09-01

The Oak Creek Power Plant is a four unit, coal-fired plant totaling 1 140 MW. The plant has a once-through circulating water system with a common forebay, from which it draws both main condenser circulating and house service water. System design prohibits thermal treatment strategies and obtaining environmental permitting for mollusicidal treatments is difficult at best. Initial treatment strategies revolved around chlorination, using sodium hypochlorite, which proved to be marginally successful, or chlorine dioxide, which raised safety concerns. This paper discusses plant design, treatment history, environmental permitting issues, design and installation of a copper ion generator, problems encountered and solutions, operating and maintenance requirements, and results to date of copper ion technology at the Energies' Oak Creek Power Plant. (orig.)

Beryllium-copper reactivity in an ITER joining environment

International Nuclear Information System (INIS)

Odegard, B.C.; Cadden, C.H.; Yang, N.Y.C.

1998-01-01

Beryllium-copper reactivity was studied using test parameters being considered for use in the ITER reactor. In this application, beryllium-copper tiles are produced using a low-temperature copper-copper diffusion bonding technique. Beryllium is joined to copper by first plating the beryllium with copper followed by diffusion bonding the electrodeposited (ED) copper to a wrought copper alloy (CuNiBe) at 450 C, 1-3 h using a hot isostatic press (HIP). In this bonded assembly, beryllium is the armor material and the CuNiBe alloy is the heat sink material. Interface temperatures in service are not expected to exceed 350 C. For this study, an ED copper-beryllium interface was subjected to diffusion bonding temperatures and times to study the reaction products. Beryllium-copper assemblies were subjected to 350, 450 and 550 C for times up to 200 h. Both BeCu and Be 2 Cu intermetallic phases were detected using scanning electron microscopy and quantitative microprobe analysis. Growth rates were determined experimentally for each phase and activation energies for formation were calculated. The activation energies were 66 mol and 62 kJ mol -1 for the BeCu and Be 2 Cu, respectively. Tensile bars were produced from assemblies consisting of coated beryllium (both sides) sandwiched between two blocks of Hycon-3. Tensile tests were conducted to evaluate the influence of these intermetallics on the bond strength. Failure occurred at the beryllium-copper interface at fracture strengths greater than 300 MPa for the room-temperature tests. (orig.)

49 CFR 192.125 - Design of copper pipe.

Science.gov (United States)

2010-10-01

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

Real-time oxide evolution of copper protected by graphene and boron nitride barriers

DEFF Research Database (Denmark)

Galbiati, Miriam; Stoot, Adam Carsten; Mackenzie, David

2017-01-01

and material science. Owing to their different electronic properties (graphene is a semimetal, whereas hBN is a wide-bandgap insulator), their protection behaviour is distinctly different. Here we investigate the performance of graphene and hBN as barrier coatings applied on copper substrates through a real......-time study in two different oxidative conditions. Our findings show that the evolution of the copper oxidation is remarkably different for the two coating materials.......Applying protective or barrier layers to isolate a target item from the environment is a common approach to prevent or delay its degradation. The impermeability of two-dimensional materials such as graphene and hexagonal boron nitride (hBN) has generated a great deal of interest in corrosion...

Real-time oxide evolution of copper protected by graphene and boron nitride barriers.

Science.gov (United States)

Galbiati, M; Stoot, A C; Mackenzie, D M A; Bøggild, P; Camilli, L

2017-01-09

Applying protective or barrier layers to isolate a target item from the environment is a common approach to prevent or delay its degradation. The impermeability of two-dimensional materials such as graphene and hexagonal boron nitride (hBN) has generated a great deal of interest in corrosion and material science. Owing to their different electronic properties (graphene is a semimetal, whereas hBN is a wide-bandgap insulator), their protection behaviour is distinctly different. Here we investigate the performance of graphene and hBN as barrier coatings applied on copper substrates through a real-time study in two different oxidative conditions. Our findings show that the evolution of the copper oxidation is remarkably different for the two coating materials.

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...

Relationship among aqueous copper half-lives and responses of Pimephales promelas to a series of copper sulfate pentahydrate concentrations.

Science.gov (United States)

Calomeni, Alyssa J; Kinley, Ciera M; Geer, Tyler D; Iwinski, Kyla J; Hendrikse, Maas; Rodgers, John H

2018-04-01

Copper algaecide exposures in situ are often of shorter duration than exposures for static toxicity experiments because aqueous concentrations in situ dissipate as a function of site-specific fate processes. Consequently, responses of organisms to static copper exposures may overestimate effects following in situ exposures. To understand the role of exposure duration for altering responses, Pimephales promelas survival was compared following static (96 h) and pulse (1.5, 4, 8, and 15 h half-lives) exposures of CuSO 4 •5H 2 O. Copper concentrations sorbed by fry indicated a consequence of different exposures. Responses of P. promelas to static exposures resulted in 96 h LC 50 s of 166 µgCu/L (95% confidence interval [CI], 142-189 µgCu/L) as soluble copper and 162 µgCu/L (CI, 140-183 µgCu/L) as acid soluble copper. Relative to static 96 h LC 50 s, exposures with half-lives of 1.5, 4 and 8 h resulted in LC 50 s 10, 3 and 2 times greater, respectively, for responses measured 96 h after exposure initiation. Copper concentrations extracted from fry exposed for 1.5, 4 and 8 h half-lives were less than the static experiment. However, copper sorbed by fry in the 15 h half-life experiment was not different than the static experiment. The relationship between 96 h LC 50 and 1/half-life was expressed using the equations y = 116 + 1360 × (R 2  = 0.97) for soluble copper and y = 147 + 1620 × (R 2  = 0.98) for acid soluble copper. Incorporation of exposure duration for predictions of P. promelas responses to copper pulse exposures increases prediction accuracy by an order of magnitude.

Serum zinc, copper, retinol-binding protein, prealbumin, and ceruloplasmin concentrations in infants receiving intravenous zinc and copper supplementation.

Science.gov (United States)

Lockitch, G; Godolphin, W; Pendray, M R; Riddell, D; Quigley, G

1983-02-01

One hundred twenty-seven newborn infants requiring parenteral nutrition were randomly assigned to receive differing amounts of zinc (40 to 400 micrograms/kg/day) and copper (20 or 40 micrograms/kg/day) supplementation within five birth weight groups (600 to 2,500 gm). The serum zinc concentration remained relatively constant in the group receiving the most zinc supplementation after two weeks of therapy, but declined sharply in the groups receiving less supplementation. No effect of increased copper intake was noted on ceruloplasmin values, but a difference in serum copper concentrations was noted at two weeks. No correlation was noted between serum zinc and copper values or among those for serum zinc, retinol-binding protein, and prealbumin. Reference ranges were defined for serum zinc, copper, retinol-binding protein, prealbumin, and ceruloplasmin in the preterm infant.

[Biohydrometallurgical technology of a complex copper concentrate process].

Science.gov (United States)

Murav'ev, M I; Fomchenko, N V; Kondrat'eva, T F

2011-01-01

Leaching of sulfide-oxidized copper concentrate of the Udokan deposit ore with a copper content of 37.4% was studied. In the course of treatment in a sulfuric acid solution with pH 1.2, a copper leaching rate was 6.9 g/kg h for 22 h, which allowed extraction of 40.6% of copper. As a result of subsequent chemical leaching at 80 degrees C during 7 h with a solution of sulphate ferric iron obtained after bio-oxidation by an association of microorganisms, the rate of copper recovery was 52.7 g/kg h. The total copper recovery was 94.5% (over 29 h). Regeneration of the Fe3+ ions was carried out by an association of moderately thermophilic microorganisms, including bacteria of genus Sulfobacillus and archaea of genus Ferroplasma acidiphilum, at 1.0 g/l h at 40 degrees C in the presence of 3% solids obtained by chemical leaching of copper concentrate. A technological scheme of a complex copper concentrate process with the use of bacterial-chemical leaching is proposed.

Evidence for organic complexed copper in sea water

Energy Technology Data Exchange (ETDEWEB)

Slowey, J F; Jeffrey, L M; Hood, D W

1967-04-22

A few attempts have been made to characterize the chemical components contributing to the copper content of seawater. About 0.3 mu/liter of particulate copper in 2 stations in the English Channel and 15 mu/liter of ultrafilterable (10 mu) but non-dialyzable copper in a sample from Texas Bay has been reported. Also the evidence has been shown for copper in the organic form in waters of the Florida Current. The occasional presence of non- dialyzable copper for many samples from the Gulf of Mexico suggests that strongly complexed copper-organic compounds are present in seawater. This communication presents evidence for such complexes that are extractable into a nonpolar solvent in the absence of any added chelating agent. Preliminary results have shown that the copper- organic complex isolated by chloroform extraction occurs in the eighth fraction of the Hirsch and Ahrens lipid separation method using silica gel chromatography. This would indicate that copper complex is associated with the phospholipid, amino lipid, or porphyrin fraction of the lipids.

Micro-Welding of Copper Plate by Frequency Doubled Diode Pumped Pulsed Nd:YAG Laser

Science.gov (United States)

Nakashiba, Shin-Ichi; Okamoto, Yasuhiro; Sakagawa, Tomokazu; Takai, Sunao; Okada, Akira

A pulsed laser of 532 nm wavelength with ms range pulse duration was newly developed by second harmonic generation of diode pumped pulsed Nd:YAG laser. High electro-optical conversion efficiency more than 13% could be achieved, and 1.5 kW peak power green laser pulse was put in optical fiber of 100 μm in diameter. In micro- welding of 1.0 mm thickness copper plate, a keyhole welding was successfully performed by 1.0 kW peak power at spot diameter less than 200 μm. The frequency doubled pulsed laser improved the processing efficiency of copper welding, and narrow and deep weld bead was stably obtained.

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.

Engineering kinetic barriers in copper metallization

International Nuclear Information System (INIS)

Huang Hanchen; Wei, H.L.; Woo, C.H.; Zhang, X.X.

2002-01-01

In metallization processes of integrated circuits, it is desirable to deposit the metal lines (aluminum or copper) fast and at low temperatures. However, the lines (films) usually consist of undesirable columns and voids, because of the absence of sufficient diffusion--a direct result of large kinetic barriers. Following the proposal and realization of the three-dimensional Ehrlich-Schwoebel (3D ES) barrier, we present here a method to engineer this kinetic barrier so as to improve quality of deposited copper films. We deposit copper films by magnetron sputtering, characterize the film structure and texture by using the scanning electron microscope and the x-ray diffraction, respectively. Taking indium as surfactant during copper deposition, we have achieved much better density and bottom coverage of copper filled trenches. The characterizations show that the improvement is the result of the 3D ES barrier reduction caused by indium addition. Engineering the 3D ES barrier therefore leads to improved film quality

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.

High-voltage many-pulses generator with inductive energy store and fuse

International Nuclear Information System (INIS)

Kovalev, V.P.; Diyankov, V.S.; Kormilitsin, A.I.; Lavrent'ev, B.N.

1996-01-01

The high-voltage generator with inductive energy store and fuses as opening switch that generate series of powerful pulses is considered. This generator differs from the ordinary generator with inductive store by the cross-section of the series copper wires. The parameters of the wires are chosen based on empirical relations. The generation principle was tested on the two high-voltage generators with characteristic impedance 2.2 ohm, 4 ohm and with output voltages of 140 kV and 420 kV, respectively. Copper wires 0.1 to 0.23 mm in diameter were used. Series of 2 to 5 pulses of 100 to 300 ns duration, 400 to 1000 kV amplitude and 1 - 10 GW power were obtained. Pulses can be both the same and different. Two successive bremsstrahlung radiation pulses were obtain on the EMIR-M and IGUR-3 devices. Series power megavolt pulses can be generated with a power exceeding 10 11 W, pulse duration of 10 -3 to 10 -6 s, and time interval between them 10 -7 to 10 -5 s. (author). 4 figs., 2 refs

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

World Copper Market Outlook: 2003-2014

OpenAIRE

Florela Stoian

2015-01-01

This paper presents synthetically the copper market outlook (demand, supply, and prices) during 2003-2014, highlighting the impact of economic crisis of 2008-2009 on the world copper market. During the crisis, the decline in demand caused increases in excess supply of metal, as the supply has followed an upward trend, contributing to the imbalances of the copper market and putting pressure on stock prices at LME London Metal Exchange.

49 CFR 192.377 - Service lines: Copper.

Science.gov (United States)

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false Service lines: Copper. 192.377 Section 192.377 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... § 192.377 Service lines: Copper. Each copper service line installed within a building must be protected...

Divalent Copper as a Major Triggering Agent in Alzheimer's Disease.

Science.gov (United States)

Brewer, George J

2015-01-01

Alzheimer's disease (AD) is at epidemic proportions in developed countries, with a steady increase in the early 1900 s, and then exploding over the last 50 years. This epidemiology points to something causative in the environment of developed countries. This paper will review the considerable evidence that that something could be inorganic copper ingestion. The epidemic parallels closely the spread of copper plumbing, with copper leached from the plumbing into drinking water being a main causal feature, aided by the increasingly common use of supplement pills containing copper. Inorganic copper is divalent copper, or copper-2, while we now know that organic copper, or copper in foods, is primarily monovalent copper, or copper-1. The intestinal transport system, Ctr1, absorbs copper-1 and the copper moves to the liver, where it is put into safe channels. Copper-2 is not absorbed by Ctr1, and some of it bypasses the liver and goes directly into the blood, where it appears to be exquisitely toxic to brain cognition. Thus, while aggregation of amyloid-β has been postulated to be the cause of AD under current dogma, the great increase in prevalence over the last century appears to be due to ingestion of copper-2, which may be causing the aggregation, and/or increasing the oxidant toxicity of the aggregates. An alternative hypothesis proposes that oxidant stress is the primary injuring agent, and under this hypothesis, copper-2 accumulation in the brain may be a causal factor of the oxidant injury. Thus, irrespective of which hypothesis is correct, AD can be classified, at least in part, as a copper-2 toxicity disease. It is relatively easy to avoid copper-2 ingestion, as discussed in this review. If most people begin avoiding copper-2 ingestion, perhaps the epidemic of this serious disease can be aborted.

Water requirements of the copper industry

Science.gov (United States)

Mussey, Orville Durey

1961-01-01

The copper industry in 1955 used about 330 million gallons of water per day in the mining and manufacturing of primary copper. This amount is about 0.3 percent of the total estimated withdrawals of industrial water in the United States in 1955. These facts were determined by a survey, in 1956, of the amount and chemical quality of the water used by the copper industry. A large part of this water was used in Arizona, Nevada, New Mexico, and Utah, where about five-sixths of the domestic copper is mined. Much of the remaining water use was near New York City where most of the electrolytic refineries are located, and the rest of the water was used in widely scattered places. A little more than 100,000 gallons of water per ton of copper was used in the production of copper from domestic ores. Of this amount about 70,000 gallons per ton was used in mining and concentrating the ore, and about 30,000 gallons per ton was used to reduce the concentrate to refined copper. In areas where water was scarce or expensive, the unit water use was a little more than half the average. About 60 mgd (million gallons per day) or 18 percent of the water was used consumptively, and nearly all of the consumptive use occurred in the water-short areas of the West. Of the water used in mining and manufacturing primary copper 75 percent was surface water and 25 percent was ground water, 89 percent of this water was self-supplied by the copper companies and 11 percent came from public supplies. Much of the water used in producing primary copper was of comparatively poor quality; about 46 percent was saline containing 1,000 ppm (parts per million) or more of dissolved solids and 54 percent was fresh. Water that is used for concentration of copper ores by flotation or even any water that comes in contact with the ore at any time before it reaches the flotation plant must be free of petroleum products because they interfere with the flotation process. The water used in mining and ore concentration

Recovery of copper and water from copper-electroplating wastewater by the combination process of electrolysis and electrodialysis.

Science.gov (United States)

Peng, Changsheng; Liu, Yanyan; Bi, Jingjing; Xu, Huizhen; Ahmed, Abou-Shady

2011-05-30

In this paper, a laboratory-scale process which combined electrolysis (EL) and electrodialysis (ED) was developed to treat copper-containing wastewater. The feasibility of such process for copper recovery as well as water reuse was determined. Effects of three operating parameters, voltage, initial Cu(2+) concentration and water flux on the recovery of copper and water were investigated and optimized. The results showed that about 82% of copper could be recovered from high concentration wastewater (HCW, >400mg/L) by EL, at the optimal conditions of voltage 2.5 V/cm and water flux 4 L/h; while 50% of diluted water could be recycled from low concentration wastewater (LCW, water flux 4 L/h. However, because of the limitation of energy consumption (EC), LCW for EL and HCW for ED could not be treated effectively, and the effluent water of EL and concentrated water of ED should be further treated before discharged. Therefore, the combination process of EL and ED was developed to realize the recovery of copper and water simultaneously from both HCW and LCW. The results of the EL-ED process showed that almost 99.5% of copper and 100% of water could be recovered, with the energy consumption of EL ≈ 3 kW h/kg and ED ≈ 2 kW h/m(3). According to SEM and EDX analysis, the purity of recovered copper was as high as 97.9%. Copyright © 2011 Elsevier B.V. All rights reserved.

Direct patterning of highly-conductive graphene@copper composites using copper naphthenate as a resist for graphene device applications.

Science.gov (United States)

Bi, Kaixi; Xiang, Quan; Chen, Yiqin; Shi, Huimin; Li, Zhiqin; Lin, Jun; Zhang, Yongzhe; Wan, Qiang; Zhang, Guanhua; Qin, Shiqiao; Zhang, Xueao; Duan, Huigao

2017-11-09

We report an electron-beam lithography process to directly fabricate graphene@copper composite patterns without involving metal deposition, lift-off and etching processes using copper naphthenate as a high-resolution negative-tone resist. As a commonly used industrial painting product, copper naphthenate is extremely cheap with a long shelf time but demonstrates an unexpected patterning resolution better than 10 nm. With appropriate annealing under a hydrogen atmosphere, the produced graphene@copper composite patterns show high conductivity of ∼400 S cm -1 . X-ray diffraction, conformal Raman spectroscopy and X-ray photoelectron spectroscopy were used to analyze the chemical composition of the final patterns. With the properties of high resolution and high conductivity, the patterned graphene@copper composites could be used as conductive pads and interconnects for graphene electronic devices with ohmic contacts. Compared to common fabrication processes involving metal evaporation and lift-off steps, this pattern-transfer-free fabrication process using copper naphthenate resist is direct and simple but allows comparable device performance in practical device applications.

A natural analogue for copper waste canisters: The copper-uranium mineralised concretions in the Permian mudrocks of south Devon, United Kingdom

International Nuclear Information System (INIS)

Milodowski, A.E.; Styles, M.T.; Hards, V.L.

2000-08-01

This report presents the results of a small-scale pilot study of the mineralogy and alteration characteristics of unusual sheet-like native copper occurring together with uraniferous and vanadiferous concretions in mudstones and siltstones of the Permian Littleham Mudstone Formation, at Littleham Cove, south Devon, England. The host mudstones and siltstones are smectitic and have been compacted through deep Mesozoic burial. The occurrence of native copper within these rocks represents a natural analogue for the long-term behaviour of copper canisters, sealed in a compacted clay (bentonite) backfill, that will be used for the deep geological disposal of high-level radioactive waste by the SKB. The study was undertaken by the British Geological Survey (BGS) on behalf of SKB between November 1999 and June 2000. The study was based primarily on archived reference material collected by the BGS during regional geological and mineralogical surveys of the area in the 1970's and 1980's. However, a brief visit was made to Littleham Cove in January 2000 to try to examine the native copper in situ and to collect additional material. Unfortunately, recent landslips and mudflows obscured much of the outcrop, and only one new sample of native copper could be collected. The native copper occurs as thin plates, up to 160 mm in diameter, which occur parallel to bedding in the Permian Littleham Mudstone Formation at Littleham Cove (near Budleigh Salterton) in south Devon. Each plate is made up of composite stacks of individual thin copper sheets each 1-2 mm thick. The copper is very pure (>99.4% Cu) but is accompanied by minor amounts of native silver (also pure - >99%) which occurs as small inclusions within the native copper. Detailed mineralogical and petrological studies of the native copper sheets, using optical petrography, backscattered scanning electron microscopy, X-ray diffraction analysis and electron probe microanalytical techniques, reveal a complex history of

A natural analogue for copper waste canisters: The copper-uranium mineralised concretions in the Permian mudrocks of south Devon, United Kingdom

Energy Technology Data Exchange (ETDEWEB)

Milodowski, A.E.; Styles, M.T.; Hards, V.L. [Natural Environment Research Council (United Kingdom). British Geological Survey

2000-08-01

This report presents the results of a small-scale pilot study of the mineralogy and alteration characteristics of unusual sheet-like native copper occurring together with uraniferous and vanadiferous concretions in mudstones and siltstones of the Permian Littleham Mudstone Formation, at Littleham Cove, south Devon, England. The host mudstones and siltstones are smectitic and have been compacted through deep Mesozoic burial. The occurrence of native copper within these rocks represents a natural analogue for the long-term behaviour of copper canisters, sealed in a compacted clay (bentonite) backfill, that will be used for the deep geological disposal of high-level radioactive waste by the SKB. The study was undertaken by the British Geological Survey (BGS) on behalf of SKB between November 1999 and June 2000. The study was based primarily on archived reference material collected by the BGS during regional geological and mineralogical surveys of the area in the 1970's and 1980's. However, a brief visit was made to Littleham Cove in January 2000 to try to examine the native copper in situ and to collect additional material. Unfortunately, recent landslips and mudflows obscured much of the outcrop, and only one new sample of native copper could be collected. The native copper occurs as thin plates, up to 160 mm in diameter, which occur parallel to bedding in the Permian Littleham Mudstone Formation at Littleham Cove (near Budleigh Salterton) in south Devon. Each plate is made up of composite stacks of individual thin copper sheets each 1-2 mm thick. The copper is very pure (>99.4% Cu) but is accompanied by minor amounts of native silver (also pure - >99%) which occurs as small inclusions within the native copper. Detailed mineralogical and petrological studies of the native copper sheets, using optical petrography, backscattered scanning electron microscopy, X-ray diffraction analysis and electron probe microanalytical techniques, reveal a complex history of

Characterization of copper oxides, iron oxides, and zinc copper ferrite desulfurization sorbents by X-ray photoelectron spectroscopy and scanning electron microscopy

Science.gov (United States)

Siriwardane, Ranjani V.; Poston, James A.

1993-05-01

Characterization of copper oxides, iron oxides, and zinc copper ferrite desulfurization sorbents was performed by X-ray photoelectron spectroscopy and scanning electron microscopy/energy-dispersive spectroscopy at temperatures of 298 to 823 K. Analysis of copper oxides indicated that the satellite structure of the Cu22p region was absent in the Cu(I) state but was present in the Cu(II) state. Reduction of CuO at room temperature was observed when the ion gauge was placed close to the sample. The satellite structure was absent in all the copper oxides at 823 K in vacuum. Differentiation of the oxidation state of copper utilizing both Cu(L 3M 4,5M 4,5) X-ray-induced Auger lines and Cu2p satellite structure, indicated that the copper in zinc copper ferrite was in the + 1 oxidation state at 823 K. This + 1 state of copper was not significantly changed after exposure to H 2, CO, and H 2O. There was an increase in Cu/Zn ratio and a decrease in Fe/Zn ratio on the surface of zinc copper ferrite at 823 K compared to that at room temperature. These conditions of copper offered the best sulfidation equilibrium for the zinc copper ferrite desulfurization sorbent. Analysis of iron oxides indicated that there was some reduction of both Fe 2O 3 and FeO at 823K. The iron in zinc copper ferrite was similar to that of Fe 2O 3 at room temperature but there was some reduction of this Fe(III) state to Fe(II) at 823 K. This reduction was more enhanced in the presence of H 2 and CO. Reduction to Fe(II) may not be desirable for the lifetime of the sorbent.

Utilization of Copper Alloys for Marine Applications

Science.gov (United States)

Drach, Andrew

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

Bonding and structure of copper nitrenes.

Science.gov (United States)

Cundari, Thomas R; Dinescu, Adriana; Kazi, Abul B

2008-11-03

Copper nitrenes are of interest as intermediates in the catalytic aziridination of olefins and the amination of C-H bonds. However, despite advances in the isolation and study of late-transition-metal multiply bonded complexes, a bona fide structurally characterized example of a terminal copper nitrene has, to our knowledge, not been reported. In anticipation of such a report, terminal copper nitrenes are studied from a computational perspective. The nitrene complexes studied here are of the form (beta-diketiminate)Cu(NPh). Density functional theory (DFT), complete active space self-consistent-field (CASSCF) electronic structure techniques, and hybrid quantum mechanical/molecular mechanical (QM/MM) methods are employed to study such species. While DFT methods indicate that a triplet (S = 1) is the ground state, CASSCF calculations indicate that a singlet (S = 0) is the ground state, with only a small energy gap between the singlet and triplet. Moreover, the ground-state (open-shell) singlet copper nitrene is found to be highly multiconfigurational (i.e., biradical) and to possess a bent geometry about the nitrene nitrogen, contrasting with the linear nitrene geometry of the triplet copper nitrenes. CASSCF calculations also reveal the existence of a closed-shell singlet state with some degree of multiple bonding character for the copper-nitrene bond.

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

Microbial leaching of low grade copper ores

International Nuclear Information System (INIS)

Rauf, A.; Ashfaq, M.

1991-01-01

Biotechnology is regarded as one of the most promising and revolutionary solution to various problems which are generally faced in the extraction of metals from their ores such as high energy, capital costs and environmental pollution. The paper deals with the study of low grade copper ores for their beneficiation and extraction of copper. The ores used were chalcopyrite and oxidized copper ores. Microorganisms play a vital role in the solubilization of valuable contents from ores such as copper and other metals. Studies have been conducted on the indigenous copper ores by using thiobacillus ferro oxidans and thiobacillus thio oxidans. For comparison purpose some experiments have also been conducted by chemical leaching. The results of bacterial leaching are encouraging. (author)

Copper-induced apical trafficking of ATP7B in polarized hepatoma cells provides a mechanism for biliary copper excretion

NARCIS (Netherlands)

Roelofsen, H; Wolters, H; Van Luyn, MJA; Miura, N; Kuipers, F; Vonk, RJ

Background & Aims: Mutations in the ATP7B gene, encoding a copper-transporting P-type adenosine triphosphatase, lead to excessive hepatic copper accumulation because of impaired biliary copper excretion in Wilson's disease. In human liver, ATP7B is predominantly localized to the trans-Golgi network,

Calibration equations for energy-dispersive XRF determination of copper, iron and lead in copper ore slurries

International Nuclear Information System (INIS)

Lakosz, M.

1976-01-01

Calibration equations for the X-ray fluorescence analysis determination of copper, iron and lead in copper ore slurries have been derived and tested. The measurement of Ksub(α) lines of copper and iron and Lsub(α) line of lead excited by rays from 238 Pu source have been used. Si/Li detector coupled to multichannel analyzer and minicomputer have been applied in measurements. The matrix and density effect have been eliminated by additional measurement of back-scattered primary radiation. (author)

The cardiac copper chaperone proteins Sco1 and CCS are up-regulated, but Cox 1 and Cox4 are down-regulated, by copper deficiency.

Science.gov (United States)

Getz, Jean; Lin, Dingbo; Medeiros, Denis M

2011-10-01

Copper is ferried in a cell complexed to chaperone proteins, and in the heart much copper is required for cytochrome c oxidase (Cox). It is not completely understood how copper status affects the levels of these proteins. Here we determined if dietary copper deficiency could up- or down-regulate select copper chaperone proteins and Cox subunits 1 and 4 in cardiac tissue of rats. Sixteen weanling male Long-Evans rats were randomized into treatment groups, one group receiving a copper-deficient diet (CCS, Sco1, Ctr1, Cox17, Cox1, and Cox4 by SDS-PAGE and Western blotting. No changes were observed in the concentrations of CTR1 and Cox17 between copper-adequate and copper-deficient rats. CCS and Sco1 were up-regulated and Cox1 and Cox4 were both down-regulated as a result of copper deficiency. These data suggest that select chaperone proteins and may be up-regulated, and Cox1 and 4 down-regulated, by a dietary copper deficiency, whereas others appear not to be affected by copper status.

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

Science.gov (United States)

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

2012-07-01

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

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

International Nuclear Information System (INIS)

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

2012-01-01

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

Operation and experience of a 2 km coated conductor REEL – to – REEL copper pulse plating facility

International Nuclear Information System (INIS)

Floegel-Delor, U; Riedel, T; Wippich, D; Rothfeld, R; Schirrmeister, P; Koenig, R; Werfel, F N; Usoskin, A; Rutt, A

2014-01-01

Bruker HTS manufactures YBCO based superconducting wires of the second generation on low- cost Stainless Steel substrate (100 μm thick). With 250 – 500 A/cm@77 K, SF, 650 MPa tensile strength and 6 mm bending radius excellent electrical and mechanical properties are achieved. As complementation of the 2G fabrication technology an automated 2 km copper pulse plating facility has been installed in 2012. We report here the operation requirements and the experiences of the copper plating technique.

Potassium sorbate-A new aqueous copper corrosion inhibitor

International Nuclear Information System (INIS)

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

2007-01-01

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

21 CFR 73.2120 - Disodium EDTA-copper.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Disodium EDTA-copper. 73.2120 Section 73.2120 Food... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2120 Disodium EDTA-copper. (a) Identity. The color additive disodium EDTA-copper is disodium [[N,N′- 1,2- ethanediylbis[N - (carboxymethyl) glycinato...

Functional recovery of biofilm bacterial communities after copper exposure