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

International Nuclear Information System (INIS)

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

2016-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2016-02-15

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

Biogeochemical spatio-temporal transformation of copper in Aspergillus niger colonies grown on malachite with different inorganic nitrogen sources.

Science.gov (United States)

Fomina, Marina; Bowen, Andrew D; Charnock, John M; Podgorsky, Valentin S; Gadd, Geoffrey M

2017-03-01

This work elucidates spatio-temporal aspects of the biogeochemical transformation of copper mobilized from malachite (Cu 2 (CO 3 )(OH) 2 ) and bioaccumulated within Aspergillus niger colonies when grown on different inorganic nitrogen sources. It was shown that the use of either ammonium or nitrate determined how copper was distributed within the colony and its microenvironment and the copper oxidation state and succession of copper coordinating ligands within the biomass. Nitrate-grown colonies yielded ∼1.7× more biomass, bioaccumulated ∼7× less copper, excreted ∼1.9× more oxalate and produced ∼1.75× less water-soluble copper in the medium in contrast to ammonium-grown colonies. Microfocus X-ray absorption spectroscopy revealed that as the mycelium matured, bioaccumulated copper was transformed from less stable and more toxic Cu(I) into less toxic Cu(II) which was coordinated predominantly by phosphate/malate ligands. With time, a shift to oxalate coordination of bioaccumulated copper occurred in the central older region of ammonium-grown colonies. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

A new integral experiment on copper with DT neutron source at JAEA/FNS

Energy Technology Data Exchange (ETDEWEB)

Kwon, Saerom, E-mail: kwon.saerom@jaea.go.jp; Sato, Satoshi; Ohta, Masayuki; Ochiai, Kentaro; Konno, Chikara

2016-11-01

Highlights: • Integral experiment on copper with DT neutron was performed under small influence of background neutrons which were efficiently absorbed in the Li{sub 2}O layers. • The experimental analyses were carried out using MCNP5-1.40 and the recent nuclear data libraries. • The underestimation issue of the reaction rates related to lower energy neutrons is focused on. • The combination of the {sup 63}Cu data in JEFF-3.2 and {sup 65}Cu data in JENDL-4.0 gave the best C/E. • The specific cross section data of copper should be reassessed. - Abstract: In order to validate copper nuclear data, an integral experiment on copper with the DT neutron source at JAEA/FNS had been performed over 20 years ago. The experiment had showed that ratios of the calculated values to the experimental ones (C/Es) related to lower energy neutrons had been drastically smaller than unity. In order to reveal reasons of the small C/Es, we newly performed the integral experiment on copper with the DT neutron source at JAEA/FNS. A quasi-cylindrical copper assembly of 315 mm in radius and 608 mm in depth was covered with Li{sub 2}O blocks of 51 mm in thickness for the front and side parts and 153 mm in thickness for the rear part to exclude background neutrons which might affect the measured data. We measured reaction rates with 5 activation foils and fission rates with 2 micro fission chambers at the center of the assembly. The experiment was analyzed by using MCNP5-1.40 with the recent nuclear data libraries, ENDF/B-VII.1, JEFF-3.2 and JENDL-4.0. As a result, the C/E of the reaction rate of the {sup 197}Au(n,γ){sup 198}Au reaction improved by 10% from the previous result and the combination of the {sup 63}Cu data in JEFF-3.2 and {sup 65}Cu data in JENDL-4.0 increased the C/E by more 10% because of the resonance data of the {sup 63}Cu in JEFF-3.2. Moreover, the calculated result with the {sup 63}Cu data in JEFF-3.2 and {sup 65}Cu data in JENDL-4.0 with 10% larger elastic

A Conceptual Framework for Primary Source Practices

Science.gov (United States)

Ensminger, David C.; Fry, Michelle L.

2012-01-01

This article introduces a descriptive conceptual framework to provide teachers with a means of recognizing and describing instructional activities that use primary sources. The framework provides structure for professional development programs that have been established to train teachers to access and integrate primary sources into lessons. The…

Bis(trialkylsilyl) peroxides as alkylating agents in the copper-catalyzed selective mono-N-alkylation of primary amides.

Science.gov (United States)

Sakamoto, Ryu; Sakurai, Shunya; Maruoka, Keiji

2017-06-13

The copper-catalyzed selective mono-N-alkylation of primary amides with bis(trialkylsilyl) peroxides as alkylating agents was reported. The results of a mechanistic study suggest that this reaction should proceed via a free radical process that includes the generation of alkyl radicals from bis(trialkylsilyl) peroxides.

How Will Copper Contamination Constrain Future Global Steel Recycling?

Science.gov (United States)

Daehn, Katrin E; Cabrera Serrenho, André; Allwood, Julian M

2017-06-06

Copper in steel causes metallurgical problems, but is pervasive in end-of-life scrap and cannot currently be removed commercially once in the melt. Contamination can be managed to an extent by globally trading scrap for use in tolerant applications and dilution with primary iron sources. However, the viability of long-term strategies can only be evaluated with a complete characterization of copper in the global steel system and this is presented in this paper. The copper concentration of flows along the 2008 steel supply chain is estimated from a survey of literature data and compared with estimates of the maximum concentration that can be tolerated in steel products. Estimates of final steel demand and scrap supply by sector are taken from a global stock-saturation model to determine when the amount of copper in the steel cycle will exceed that which can be tolerated. Best estimates show that quantities of copper arising from conventional scrap preparation can be managed in the global steel system until 2050 assuming perfectly coordinated trade and extensive dilution, but this strategy will become increasingly impractical. Technical and policy interventions along the supply chain are presented to close product loops before this global constraint.

Analysis of primary teacher stress' sources

Directory of Open Access Journals (Sweden)

Katja Depolli Steiner

2011-12-01

Full Text Available Teachers are subject to many different work stressors. This study focused on differences in intensity and frequency of potential stressors facing primary schoolteachers and set the goal to identify the most important sources of teacher stress in primary school. The study included 242 primary schoolteachers from different parts of Slovenia. We used Stress Inventory that is designed for identification of intensity and frequency of 49 situations that can play the role of teachers' work stressors. Findings showed that the major sources of stress facing teachers are factors related to work overload, factors stemming from pupils' behaviour and motivation and factors related to school system. Results also showed some small differences in perception of stressors in different groups of teachers (by gender and by teaching level.

Teaching Discrete Mathematics Entirely from Primary Historical Sources

Science.gov (United States)

Barnett, Janet Heine; Bezhanishvili, Guram; Lodder, Jerry; Pengelley, David

2016-01-01

We describe teaching an introductory discrete mathematics course entirely from student projects based on primary historical sources. We present case studies of four projects that cover the content of a one-semester course, and mention various other courses that we have taught with primary source projects.

Design and performance of a high intensity copper atom beam source nozzle for use in inelastic atom--atom collision experiments

International Nuclear Information System (INIS)

Santavicca, D.A.

1975-01-01

The research was aimed at developing a neutral copper atom beam source which could be used to study the collision cross sections for electronic excitation of neutral copper atoms in collision with neutral argon atoms. Of particular interest is the excitation from the ground state to the two upper laser levels at 3.80 and 3.82 electron volts

Aluminium and copper analysis in metallic alloys by neutron activation analysis from an 241 Am-Be source

International Nuclear Information System (INIS)

Carvalho, J. de.

1980-01-01

Aluminium and copper have been determined in aluminium alloys by the method of activation with neutrons from an 241 Am-Be source of intensity 9,8 x 10 6 n/s. The activity induced due to reactions 27 Al (n, γ) 28 Al and 63 Cu (n, γ) 64 Cu have been measured with a NaI (Tl) detector coupled to a single channel system. In order to obtain the samples and standards of about the same composition, the material to be irradiated was powdered. In view of low intensity of neutron source it was necessary to use samples of up to 50 g. A series of preliminary irradiations were carried out to ensure that the geometry for the irradiation and for the counting are reproducible. The results have been compared with those obtained by chemical methods. Assuming that the results obtained by chemical method is exact, a maximum relative error of 3,6% is obtained by this method. The method has a good reproducibility. The time needed for analysis of aluminium and copper are 18 min and 2 hours 40 minutes respectively. Four different samples were analysed. The average of five measurements for one of the samples was: 88.0% for aluminium and 10.0% for copper. The standard deviation and coefficient of variation were 0,8 and 1.0% for aluminium and 0,2 and 2.0% for copper. (author)

Teaching and Learning Mathematics from Primary Historical Sources

Science.gov (United States)

Barnett, Janet Heine; Lodder, Jerry; Pengelley, David

2016-01-01

Why would anyone think of teaching and learning mathematics directly from primary historical sources? We aim to answer this question while sharing our own experiences, and those of our students across several decades. We will first describe the evolution of our motivation for teaching with primary sources, and our current view of the advantages…

Optical emission spectra of a copper plasma produced by a metal vapour vacuum arc plasma source

International Nuclear Information System (INIS)

Yotsombat, B.; Poolcharuansin, P.; Vilaithong, T.; Davydov, S.; Brown, I.G.

2001-01-01

Optical emission spectroscopy in the range 200-800 nm was applied for investigation of the copper plasma produced by a metal vapour vacuum arc plasma source. The experiments were conducted for the cases when the plasma was guided by straight and Ω-shaped curved solenoids as well as without solenoids, and also for different vacuum conditions. It was found that, besides singly- and doubly-charged ions, a relatively high concentration of excited neutral copper atoms was present in the plasma. The relative fraction of excited atoms was much higher in the region close to the cathode surface than in the plasma column inside the solenoid. The concentration of excited neutral, singly- and doubly-ionized atoms increased proportionally when the arc current was increased to 400 A. Some weak lines were attributed to more highly ionized copper species and impurities in the cathode material. (author)

Alkylsilyl Peroxides as Alkylating Agents in the Copper-Catalyzed Selective Mono-N-Alkylation of Primary Amides and Arylamines.

Science.gov (United States)

Sakamoto, Ryu; Sakurai, Shunya; Maruoka, Keiji

2017-07-06

The copper-catalyzed selective mono-N-alkylation of primary amides or arylamines using alkylsilyl peroxides as alkylating agents is reported. The reaction proceeds under mild reaction conditions and exhibits a broad substrate scope with respect to the alkylsilyl peroxides, as well as to the primary amides and arylamines. Mechanistic studies suggest that the present reaction should proceed through a free-radical process that includes alkyl radicals generated from the alkylsilyl peroxides. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

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 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.

Energy and environmental implications of copper production

Energy Technology Data Exchange (ETDEWEB)

Alvardo, Sergio [Chile Univ., Dept. of Mechanical Engineering, Santiago (Chile); Maldonado, Pedro; Jaques, Ivan [Chile Univ., Energy Research Program, Santiago (Chile)

1999-04-01

Primary copper production is a major activity in the mining sector. It is highly energy-intensive, ranking third in specific energy consumption (SEC) among the five major basic metals (aluminum, copper, iron, lead and zinc) and poses important environmental hazards. We examine the large discrepancy between theoretical (from thermodynamics) and actual (from empirical data) SECs and then describe relevant environmental issues, focusing on the most significant energy-related environmental impacts of primary copper production with emphasis on greenhouse-gas (GHG) emissions. An example of GHG energy-related abatement that concurrently improves energy use is presented. (Author)

N-heterocyclic carbene copper(I) catalysed N-methylation of amines using CO2

KAUST Repository

Santoro, Orlando

2015-09-30

The N-methylation of amines using CO2 and PhSiH3 as source of CH3 was efficiently performed using a N-heterocyclic carbene copper(I) complex. The methodology was found compatible with aromatic and aliphatic primary and secondary amines. Synthetic and computational studies have been carried out to support the proposed reaction mechanism for this transformation.

N-heterocyclic carbene copper(I) catalysed N-methylation of amines using CO2

KAUST Repository

Santoro, Orlando; Lazreg, Faï ma; Minenkov, Yury; Cavallo, Luigi; Cazin, Catherine S. J.

2015-01-01

The N-methylation of amines using CO2 and PhSiH3 as source of CH3 was efficiently performed using a N-heterocyclic carbene copper(I) complex. The methodology was found compatible with aromatic and aliphatic primary and secondary amines. Synthetic and computational studies have been carried out to support the proposed reaction mechanism for this transformation.

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

Primary Sources and Inquiry Learning

Science.gov (United States)

Pappas, Marjorie L.

2006-01-01

In this article, the author discusses inquiry learning and primary sources. Inquiry learning puts students in the active role of investigators. Questioning, authentic and active learning, and interactivity are a few of the characteristics of inquiry learning that put the teacher and library media specialist in the role of coaches while students…

Source and Assessment of Metal Pollution at Khetri Copper Mine Tailings and Neighboring Soils, Rajasthan, India.

Science.gov (United States)

Punia, Anita; Siddaiah, N Siva; Singh, Saurabh K

2017-11-01

We present here the results of the study on metal pollution by identifying source, abundance and distribution in soil and tailings of Khetri copper complex (KCC) mines, Rajasthan India. The region is highly contaminated by copper (Cu) with higher values in the soil near overburden material (1224 mg/kg) and tailings (111 mg/kg). The average Cu (231 mg/kg) concentration of soil is ~9, 5 and 32 times higher than upper crust, world average shale (WAS) and local background soil (LS), respectively. However this reaches to ~82, 46 and 280 times higher in case of tailing when compared. The correlation and principal component analysis for soil reveals that the source of Cu, Zn, Co, Ni, Mn and Fe is mining and Pb and Cd could be result of weathering of parent rocks and other anthropogenic activities. The source for Cr in soil is both mining activities and weathering of parent rocks. The values of index of geo-accumulation (I geo ) and pollution load index for soil using LS as background are higher compared to values calculated using WAS. The metal rich sulphide bearing overburden material as well as tailings present in the open environment at KCC mines region warrants a proper management to minimize their impact on the environment.

Selective Formation of Secondary Amides via the Copper-Catalyzed Cross-Coupling of Alkylboronic Acids with Primary Amides

Science.gov (United States)

Rossi, Steven A.; Shimkin, Kirk W.; Xu, Qun; Mori-Quiroz, Luis M.; Watson, Donald A.

2014-01-01

For the first time, a general catalytic procedure for the cross coupling of primary amides and alkylboronic acids is demonstrated. The key to the success of this reaction was the identification of a mild base (NaOSiMe3) and oxidant (di-tert-butyl peroxide) to promote the copper-catalyzed reaction in high yield. This transformation provides a facile, high-yielding method for the mono-alkylation of amides. PMID:23611591

Efficient SN2 fluorination of primary and secondary alkyl bromides by copper(I) fluoride complexes

KAUST Repository

Liu, Yanpin; Chen, Chaohuang; Li, Huaifeng; Huang, Kuo-Wei; Tan, Jianwei; Weng, Zhiqiang

2013-01-01

Copper(I) fluoride complexes ligated by phenanthroline derivatives have been synthesized and structurally characterized by X-ray crystallography. These complexes adopt as either ionic or neutral forms in the solid state, depending on the steric bulkiness of the substituent groups on the phenanthroline ligands. These complexes react with primary and secondary alkyl bromides to produce the corresponding alkyl fluorides in modest to good yields. This new method is compatible with a variety of important functional groups such as ether, thioether, amide, nitrile, methoxyl, hydroxyl, ketone, ester, and heterocycle moieties. © 2013 American Chemical Society.

Efficient SN2 fluorination of primary and secondary alkyl bromides by copper(I) fluoride complexes

KAUST Repository

Liu, Yanpin

2013-11-11

Copper(I) fluoride complexes ligated by phenanthroline derivatives have been synthesized and structurally characterized by X-ray crystallography. These complexes adopt as either ionic or neutral forms in the solid state, depending on the steric bulkiness of the substituent groups on the phenanthroline ligands. These complexes react with primary and secondary alkyl bromides to produce the corresponding alkyl fluorides in modest to good yields. This new method is compatible with a variety of important functional groups such as ether, thioether, amide, nitrile, methoxyl, hydroxyl, ketone, ester, and heterocycle moieties. © 2013 American Chemical Society.

Development of halide copper vapor laser (the characteristics of using Cul)

International Nuclear Information System (INIS)

Oouti, Kazumi; Wada, Yukio; Sasao, Nobuyuki

1990-01-01

We are developing halide copper vapor laser that is high efficiency and high reputation rate visible laser. Halide copper vapor laser uses halide copper of copper vapor source. It melts low temperature in comporison with metal copper, because laser tube structure is very simple and it can operate easy. This time, we experiment to use Cul for copper vapor source. We resulted maximum output energy 17.8 (W) and maximum efficiency 0.78 (%) when operate condition was reputation rate 30 (kHz), gas pressure 90 (Torr), charging voltage 13 (kV). (author)

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

Fact sheet: National primary drinking water regulations for lead and copper

International Nuclear Information System (INIS)

1991-05-01

The Fact Sheet contains a summary of what the regulations will do, establish, and provide; regulatory impact in regards to benefits and costs; treatment technique requirements; tap water monitoring for lead and copper; water quality monitoring (other than lead and copper); monitoring schedules, regulatory schedules for large, medium-sized, and small systems

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

Forensic discrimination of copper wire using trace element concentrations.

Science.gov (United States)

Dettman, Joshua R; Cassabaum, Alyssa A; Saunders, Christopher P; Snyder, Deanna L; Buscaglia, JoAnn

2014-08-19

Copper may be recovered as evidence in high-profile cases such as thefts and improvised explosive device incidents; comparison of copper samples from the crime scene and those associated with the subject of an investigation can provide probative associative evidence and investigative support. A solution-based inductively coupled plasma mass spectrometry method for measuring trace element concentrations in high-purity copper was developed using standard reference materials. The method was evaluated for its ability to use trace element profiles to statistically discriminate between copper samples considering the precision of the measurement and manufacturing processes. The discriminating power was estimated by comparing samples chosen on the basis of the copper refining and production process to represent the within-source (samples expected to be similar) and between-source (samples expected to be different) variability using multivariate parametric- and empirical-based data simulation models with bootstrap resampling. If the false exclusion rate is set to 5%, >90% of the copper samples can be correctly determined to originate from different sources using a parametric-based model and >87% with an empirical-based approach. These results demonstrate the potential utility of the developed method for the comparison of copper samples encountered as forensic evidence.

Source Apportionment of Primary and Secondary Fine Particulate Matter in China

Science.gov (United States)

Hu, J.; Zhang, H.; Ying, Q.

2015-12-01

In the past few decades, China have been facing extreme particulate matter (PM) pollution problems due to the combination of fast increase of population, industrialization, urbanization and associated energy consumption and lagging of sufficient emission control measures. Studies have identified the major components of fine PM (PM2.5) in China include primary PM (which is directly emitted into the atmosphere), sulfate and nitrate (which are mainly secondary PM, i.e., formed from gaseous precursors), and organic aerosols (which can be primary or secondary). Contributions of different source sectors to the different PM components are substantially different; therefore source apportionment of these components can provide critical information needed for policy makers to design effective emission control strategies. In the current study, a source-oriented version of the Community Multiscale Air Quality (CMAQ) model that directly tracks the contributions from multiple emission sources to primary and secondary PM2.5 is developed, and then applied to determine the regional contributions of power, industry, transportation and residential sectors to primary PM, nitrate and sulfate concentrations in China. Four months in 2012-2013 are simulated to predict the seasonal variations of source contributions. Model predictions are evaluated with ambient measured concentrations. The source-oriented CMAQ model is capable of reproducing most of the available PM10 and PM2.5 mass, and PM2.5 EC, POC, nitrate and sulfate observations. Predicted source contributions for EC also generally agree with to the source contributions estimated by receptor models reported in previous studies. Model predictions suggest residential is a major contributor to primary PM (30-70%) in the spring and winter, and industrial contributes 40-60% of primary PM in the summer and fall; Transportation is an important source for EC (20-30%); Power sector is the dominating source of nitrate and sulfate in both

Access to primary energy sources - the basis of national energy security

Science.gov (United States)

Szlązak, Jan; Szlązak, Rafał A.

2017-11-01

National energy security is of fundamental importance for economic development of a country. To ensure such safety energy raw material, also called primary energy sources, are necessary. Currently in Poland primary energy sources include mainly fossil fuels, such as hard coal, brown coal, natural gas and crude oil. Other sources, e.g. renewable energy sources account for c. 15% in the energy mix. Primary energy sources are used to produce mainly electricity, which is considered as the cleanest form of energy. Poland does not have, unfortunately, sufficient energy sources and is forced to import some of them, mainly natural gas and crude oil. The article presents an insightful analysis of energy raw material reserves possessed by Poland and their structure taking account of the requirements applicable in the European Union, in particular, those related to environmental protection. The article also describes demand for electricity now and in the perspective of 2030. Primary energy sources necessary for its production have also been given. The article also includes the possibilities for the use of renewable energy sources in Poland, however, climatic conditions there are not are not particularly favourable to it. All the issues addressed in the article are summed up and ended with conclusions.

Some aspects of copper metabolism in Brindled mice

International Nuclear Information System (INIS)

Prins, H.W.

1981-01-01

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

Experience with copper oxide production in antiproton source components at Fermi National Accelerator Laboratory

International Nuclear Information System (INIS)

Ader, Christine R.; Harms, Elvin R. Jr; Morgan, James P.

2000-01-01

The Antiproton (Pbar) Source at Fermi National Accelerator Laboratory is a facility comprised of a target station, two rings called the Debuncher and Accumulator and the transport lines between those rings and the remainder of the particle accelerator complex. Water is by far the most common medium for carrying excess heat away from components, primarily electromagnets, in this facility. The largest of the water systems found in Pbar is the 95 degree Fahrenheit Low Conductivity Water (LCW) system. LCW is water which has had free ions removed, increasing its resistance to electrical current. This water circuit is used to cool magnets, power supplies, and stochastic cooling components and typically has a resistivity of 11--18 megaohms-cm. For more than ten years the Antiproton rings were plagued with overheating magnets due to plugged water-cooling channels. Various repairs have been tried over the years with no permanent success. Throughout all of this time, water samples have indicated copper oxide, CuO, as the source of the contamination. Matters came to a head in early 1997 following a major underground LCW leak between the Central Utilities Building and the Antiproton Rings enclosures. Over a span of several weeks following system turn-on, some twenty magnets overheated leading to unreliable Pbar source operation. Although it was known that oxygen in the system reacts with the copper tubing to form CuO, work to remedy this problem was not undertaken until this time period. Leaks, large quantities of make-up water, infrequent filter replacement, and thermal cycling also result in an increase in the corrosion product release rate. A three-pronged approach has been implemented to minimize the amount of copper oxide available to plug the magnets: (1) installation of an oxygen removal system capable of achieving dissolved oxygen concentrations in the parts per billion (ppb) range; (2) regular closed-loop filter/flushing of the copper headers and magnets and stainless

77 FR 11390 - Delegation of National Emission Standards for Hazardous Air Pollutants for Source Categories; Nevada

Science.gov (United States)

2012-02-27

... Source Categories. Subpart ZZZZZZ--NESHAP: Area Source Standards for Aluminum, Copper, and Other... Perchloroethylene Dry X X X Cleaning. N Hard and Decorative X X X Chromium Electroplating and Chromium Anodizing... Publishing X X X Industry. LL Primary Aluminum Reduction X X Plants. MM Chemical Recovery X X Combustion...

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

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.

Source contributions and regional transport of primary particulate matter in China

International Nuclear Information System (INIS)

Hu, Jianlin; Wu, Li; Zheng, Bo; Zhang, Qiang; He, Kebin; Chang, Qing; Li, Xinghua; Yang, Fumo; Ying, Qi; Zhang, Hongliang

2015-01-01

A source-oriented CMAQ was applied to determine source sector/region contributions to primary particulate matter (PPM) in China. Four months were simulated with emissions grouped to eight regions and six sectors. Predicted elemental carbon (EC), primary organic carbon (POC), and PPM concentrations and source contributions agree with measurements and have significant spatiotemporal variations. Residential is a major contributor to spring/winter EC (50–80%), POC (60%–90%), and PPM (30–70%). For summer/fall, industrial contributes 30–50% for EC/POC and 40–60% for PPM. Transportation is more important for EC (20–30%) than POC/PPM ( 90% in Beijing. - Highlights: • A source-oriented CMAQ was established for primary particulate matter (PPM). • Source and region contributions to EC, POC and PPM in China were quantified. • Residential is major in spring/winter and industrial dominates in summer/fall. • Open burning is more important for southern while dust is in contrast. • Both local and Heibei emissions contribute to PPM in Beijing. - Source and region contributions to primary particulate matter in China were quantified for four months during 2012-2013. Residential and industrial are the major contributors.

Bring History Alive with Primary Sources

Science.gov (United States)

Lehman, Kathy

2010-01-01

Using primary sources such as a photograph from the Library of Congress American Memory collection engages learners to think about the past and relate it to their life today. Some artifacts come with an explanation, while some do not. These require critical thinking and investigation to locate information and hypothesize answers to questions posed…

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

African Journals Online (AJOL)

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

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.

The influence of copper concentration and source on ileal microbiota.

Science.gov (United States)

Pang, Y; Patterson, J A; Applegate, T J

2009-03-01

Copper is normally supplemented in poultry diets as a growth promotant and antimicrobial. However, there are conflicting reports about the growth benefits and little information about how Cu affects the microbiota in the intestinal tract of poultry. Therefore, in vitro and in vivo experiments were conducted with broilers to determine the effects of Cu source and supplementation on ileal microbiota. The influence of Cu on growth of lactobacilli and Escherichia coli in media inoculated with ileal contents was determined in the first study. When Cu sulfate pentahydrate was supplemented to the cultures, quadratic increases in lactobacilli to graded concentrations of Cu up to 125 mg/kg and quadratic decreases in E. coli up to 250 mg/kg of Cu were observed after 24 h of incubation at 37 degrees C. However, when tribasic Cu chloride (TBCC) was supplemented, neither linear nor quadratic responses to graded concentrations of dietary Cu were observed on number of lactobacilli or number of E. coli. The effects of Cu and Cu source on ileal microbiota and growth performance in broiler chickens were determined in the second study. Bird performance was not affected by Cu source or concentration. The bacterial culture enumeration results revealed that supplementation with 187.5 mg/kg of Cu from Cu sulfate pentahydrate and TBCC had no effect on number of ileal lactobacilli of birds. The denaturing gradient gel electrophoresis analyses of ileal microbial communities revealed that neither Cu supplementation nor source had effects on the number of bacterial species predominant in the ileal digesta or associated with the ileal mucosa. Supplementation with TBCC supplementation significantly increased the similarity coefficients of microbiota in the ileal mucosa compared with cross-products of all individuals. This suggests that TBCC may alter the intestinal microbiota, yet this shift had no effect on bird performance.

United States copper metal and scrap use and trade patterns, 1995‒2014

Science.gov (United States)

Goonan, Thomas G.

2016-06-17

In 1995, China accounted for 10 percent of world copper consumption. By 2014, China accounted for about 49 percent of world copper consumption. This change has affected global copper and copper scrap prices, the sources of copper supply, and U.S. trade of copper-containing materials.

PHYTOAVAILABILITY OF COPPER IN INDUSTRIAL BY-PRODUCTS AND MINERAL FERTILIZERS

Directory of Open Access Journals (Sweden)

Camila Prado Cenciani de Souza

2015-04-01

Full Text Available Alternative copper (Cu sources could be used in fertilizer production, although the bioavailability of copper in these materials is unknown. The objective of this study was to evaluate the extractants neutral ammonium citrate (NAC, 2 % citric acid, 1 % acetic acid, 10 % HCl, 10 % H2SO4, buffer solution pH 6.0, DTPA, EDTA, water, and hot water in the quantification of available Cu content in several sources, relating them to the relative agronomic efficiency (RAE of wheat grown in a clayey Latossolo Vermelho eutrófico (Oxisol and Neossolo Quartzarênico (Typic Quartzipsamment. Copper was applied at the rate of 1.5 mg kg-1 as scrap slag, brass slag, Cu ore, granulated copper, and copper sulfate. The extractants 10 % HCl, 10 % H2SO4, and NAC extracted higher Cu concentrations. The RAE values of brass slag and Cu ore were similar to or higher than those of Cu sulfate and granulated Cu. Solubility in the 2nd NAC extractant, officially required for mineral fertilizers with Cu, was lower than 60 % for the scrap slag, Cu ore, and granulated copper sources. This fact indicates that adoption of the NAC extractant may be ineffective for industrial by-products, although no extractant was more efficient in predicting Cu availability for wheat fertilized with the Cu sources tested.

Effects of temperature, pressure and pure copper added to source material on the CuGaTe{sub 2} deposition using close spaced vapor transport technique

Energy Technology Data Exchange (ETDEWEB)

Abounachit, O. [LP2M2E, Faculté des Sciences et Techniques, Université Cadi Ayyad, Gueliz, BP 549 , Marrakech, Maroc (Morocco); Chehouani, H., E-mail: chehouani@hotmail.fr [LP2M2E, Faculté des Sciences et Techniques, Université Cadi Ayyad, Gueliz, BP 549 , Marrakech, Maroc (Morocco); Djessas, K. [CNRS-PROMES Tecnosud, Rambla de la Thermodynamique, 66100 Perpignan (France)

2013-07-01

The quality of CuGaTe{sub 2} (CGT) thin films elaborated by close spaced vapor transport technique has been studied as a function of the source temperature (T{sub S}), iodine pressure (P{sub I2}) and the amount (X{sub Cu}) of pure copper added to the stoichiometric starting material. A thermodynamic model was developed for the Cu–Ga–Te–I system to describe the CGT deposition. The model predicts the solid phase composition with possible impurities for the operating conditions previously mentioned. The conditions of stoichiometric and near-stoichiometric deposition were determined. The value of T{sub S} must range from 450 to 550 °C for P{sub I2} varying between 0.2 and 7 kPa. Adding an amount up to 10% of pure copper to the starting material improves the quality of the deposit layers and lowers the operating interval temperature to 325–550 °C. These optimal conditions were tested experimentally at 480 °C and 500 °C. The X-ray diffraction, scanning electron microscopy, and energy dispersive spectroscopy have proved that the addition of pure copper to the stoichiometric source material can be considered as a supplementary operating parameter to improve the quality of CGT thin films. - Highlights: • The stoichiometric CuGaTe{sub 2} (CGT) has been deposited by close spaced vapor transport. • The Cu–Ga–Te–I system has been studied theoretically by minimizing the Gibbs energy. • The quality of thin films has been improved by pure copper added to the source CGT. • The temperature, pressure and the amount of copper added to grow CGT are determined. • The thermodynamic predictions are in good agreement with experimental results.

Research on Primary Shielding Calculation Source Generation Codes

Science.gov (United States)

Zheng, Zheng; Mei, Qiliang; Li, Hui; Shangguan, Danhua; Zhang, Guangchun

2017-09-01

Primary Shielding Calculation (PSC) plays an important role in reactor shielding design and analysis. In order to facilitate PSC, a source generation code is developed to generate cumulative distribution functions (CDF) for the source particle sample code of the J Monte Carlo Transport (JMCT) code, and a source particle sample code is deveoped to sample source particle directions, types, coordinates, energy and weights from the CDFs. A source generation code is developed to transform three dimensional (3D) power distributions in xyz geometry to source distributions in r θ z geometry for the J Discrete Ordinate Transport (JSNT) code. Validation on PSC model of Qinshan No.1 nuclear power plant (NPP), CAP1400 and CAP1700 reactors are performed. Numerical results show that the theoretical model and the codes are both correct.

40 CFR 464.20 - Applicability; description of the copper casting subcategory.

Science.gov (United States)

2010-07-01

... copper casting subcategory. 464.20 Section 464.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS METAL MOLDING AND CASTING POINT SOURCE CATEGORY Copper Casting Subcategory § 464.20 Applicability; description of the copper casting subcategory. The...

Methods of making copper selenium precursor compositions with a targeted copper selenide content and precursor compositions and thin films resulting therefrom

Science.gov (United States)

Curtis, Calvin J [Lakewood, CO; Miedaner, Alexander [Boulder, CO; van Hest, Marinus Franciscus Antonius Maria; Ginley, David S [Evergreen, CO; Leisch, Jennifer [Denver, CO; Taylor, Matthew [West Simsbury, CT; Stanbery, Billy J [Austin, TX

2011-09-20

Precursor compositions containing copper and selenium suitable for deposition on a substrate to form thin films suitable for semi-conductor applications. Methods of forming the precursor compositions using primary amine solvents and methods of forming the thin films wherein the selection of temperature and duration of heating controls the formation of a targeted species of copper selenide.

Morphology, composition, and mixing state of primary particles from combustion sources - crop residue, wood, and solid waste.

Science.gov (United States)

Liu, Lei; Kong, Shaofei; Zhang, Yinxiao; Wang, Yuanyuan; Xu, Liang; Yan, Qin; Lingaswamy, A P; Shi, Zongbo; Lv, Senlin; Niu, Hongya; Shao, Longyi; Hu, Min; Zhang, Daizhou; Chen, Jianmin; Zhang, Xiaoye; Li, Weijun

2017-07-11

Morphology, composition, and mixing state of individual particles emitted from crop residue, wood, and solid waste combustion in a residential stove were analyzed using transmission electron microscopy (TEM). Our study showed that particles from crop residue and apple wood combustion were mainly organic matter (OM) in smoldering phase, whereas soot-OM internally mixed with K in flaming phase. Wild grass combustion in flaming phase released some Cl-rich-OM/soot particles and cardboard combustion released OM and S-rich particles. Interestingly, particles from hardwood (pear wood and bamboo) and softwood (cypress and pine wood) combustion were mainly soot and OM in the flaming phase, respectively. The combustion of foam boxes, rubber tires, and plastic bottles/bags in the flaming phase released large amounts of soot internally mixed with a small amount of OM, whereas the combustion of printed circuit boards and copper-core cables emitted large amounts of OM with Br-rich inclusions. In addition, the printed circuit board combustion released toxic metals containing Pb, Zn, Sn, and Sb. The results are important to document properties of primary particles from combustion sources, which can be used to trace the sources of ambient particles and to know their potential impacts in human health and radiative forcing in the air.

Generation of copper, nickel, and CuNi alloy nanoparticles by spark discharge

International Nuclear Information System (INIS)

Muntean, Alex; Wagner, Moritz; Meyer, Jörg; Seipenbusch, Martin

2016-01-01

The generation of copper, nickel, and copper-nickel alloy nanoparticles by spark discharge was studied, using different bespoke alloy feedstocks. Roughly spherical particles with a primary particle Feret diameter of 2–10 nm were produced and collected in agglomerate form. The copper-to-nickel ratios determined by Inductively coupled plasma mass spectrometry (ICP-MS), and therefore averaged over a large number of particles, matched the nominal copper content quite well. Further investigations showed that the electrode compositions influenced the evaporation rate and the primary particle size. The evaporation rate decreased with increasing copper content, which was found to be in good accordance with the Llewellyn-Jones model. However, the particle diameter was increasing with an increasing copper content, caused by a decrease in melting temperature due to the lower melting point of copper. Furthermore, the alloy compositions on the nanoscale were investigated via EDX. The nanoparticles exhibited almost the same composition as the used alloy feedstock, with a deviation of less than 7 percentage points. Therefore, no segregation could be detected, indicating the presence of a true alloy even on the nanoscale.

The World of Barilla Taylor: Bringing History to Life through Primary Sources.

Science.gov (United States)

Stearns, Liza

1997-01-01

Presents a lesson plan using material from a primary source-based curriculum kit titled "The World of Barilla Taylor." The kit uses personal letters, maps, hospital and work records, and other primary sources to document the life of a young woman working in the textile mills in 19th-century Massachusetts. (MJP)

Low Hepatic Tissue Copper in Pediatric Nonalcoholic Fatty Liver Disease.

Science.gov (United States)

Mendoza, Michael; Caltharp, Shelley; Song, Ming; Collin, Lindsay; Konomi, Juna V; McClain, Craig J; Vos, Miriam B

2017-07-01

Animal models and studies in adults have demonstrated that copper restriction increases severity of liver injury in nonalcoholic fatty liver disease (NAFLD). This has not been studied in children. We aimed to determine if lower tissue copper is associated with increased NAFLD severity in children. This was a retrospective study of pediatric patients who had a liver biopsy including a hepatic copper quantitation. The primary outcome compared hepatic copper concentration in NAFLD versus non-NAFLD. Secondary outcomes compared hepatic copper levels against steatosis, fibrosis, lobular inflammation, balloon degeneration, and NAFLD activity score (NAS). The study analysis included 150 pediatric subjects (102 with NAFLD and 48 non-NAFLD). After adjusting for age, body mass index z score, gamma glutamyl transferase, alanine aminotransferase, and total bilirubin, NAFLD subjects had lower levels of hepatic copper than non-NAFLD (P = 0.005). In addition, tissue copper concentration decreased as steatosis severity increased (P steatosis alone. Further studies are needed to explore the relationship between copper levels and NAFLD progression.

An Investigation of Low Biofouling Copper-charged Membranes

Science.gov (United States)

Asapu, Sunitha

Water is essential for the survival of life on Earth, but pollutants in water can cause dangerous diseases and fatalities. The need for purified water has been increasing with increasing world population; however, natural sources of water such as rivers, lakes and streams, are progressively falling shorter and shorter of meeting water needs. The provision of clean, drinkable water to people is a key factor for the development of novel and alternative water purification technologies, such as membrane separations. Nanofiltration (NF) is a membrane separations technology that purifies water from lower quality sources, such as brackish water, seawater and wastewater. During the filtration of such sources, materials that are rejected by the membrane may accumulate on the surface of the membrane to foul it. Such materials include organic and inorganic matter, colloids, salts and microorganisms. The former four can often be controlled via pretreatment; however, the accumulation of microorganisms is more problematic to membranes. Biofouling is the accumulation and growth of microorganisms on the surface of membranes and on feed spacers. After attachment, microorganisms excrete extracellular polymeric substances (EPS), which form a matrix around the organism's outer surface as biofilm. These biofilms are detrimental and result in irreversible membrane fouling. Copper and silver ions inactivate the bacterial cells and prevent the DNA replication in microbial cells. Previous studies using copper-charged feed spacers have shown the ability of copper to control biofouling without a significant amount of copper leaching from copper-charged polypropylene (PP) feed spacers during crossflow filtration. Also, filtration using unmodified speed facers experienced almost 70% flux decline, while filtration using copper-charged feed spacers displayed only 25% flux decline. These intriguing results led to the hypothesis that the polymer chemistry could be extrapolated to produce membranes

CopperCore 2.2

NARCIS (Netherlands)

Martens, Harrie; Vogten, Hubert; Koper, Rob

2005-01-01

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

Primary sources of PM2.5 organic aerosol in an industrial Mediterranean city, Marseille

Science.gov (United States)

El Haddad, I.; Marchand, N.; Wortham, H.; Piot, C.; Besombes, J.-L.; Cozic, J.; Chauvel, C.; Armengaud, A.; Robin, D.; Jaffrezo, J.-L.

2011-03-01

Marseille, the most important port of the Mediterranean Sea, represents a challenging case study for source apportionment exercises, combining an active photochemistry and multiple emission sources, including fugitive emissions from industrial sources and shipping. This paper presents a Chemical Mass Balance (CMB) approach based on organic markers and metals to apportion the primary sources of organic aerosol in Marseille, with a special focus on industrial emissions. Overall, the CMB model accounts for the major primary anthropogenic sources including motor vehicles, biomass burning and the aggregate emissions from three industrial processes (heavy fuel oil combustion/shipping, coke production and steel manufacturing) as well as some primary biogenic emissions. This source apportionment exercise is well corroborated by 14C measurements. Primary OC estimated by the CMB accounts on average for 22% of total OC and is dominated by the vehicular emissions that contribute on average for 17% of OC mass concentration (vehicular PM contributes for 17% of PM2.5). Even though industrial emissions contribute only 2.3% of the total OC (7% of PM2.5), they are associated with ultrafine particles (Dpheavy metals such as Pb, Ni and V. On one hand, given that industrial emissions governed key primary markers, their omission would lead to substantial uncertainties in the CMB analysis performed in areas heavily impacted by such sources, hindering accurate estimation of non-industrial primary sources and secondary sources. On the other hand, being associated with bursts of submicron particles and carcinogenic and mutagenic components such as PAH, these emissions are most likely related with acute ill-health outcomes and should be regulated despite their small contributions to OC. Another important result is the fact that 78% of OC mass cannot be attributed to the major primary sources and, thus, remains un-apportioned. We have consequently critically investigated the uncertainties

The primary ion source for construction and optimization of operation parameters

International Nuclear Information System (INIS)

Synowiecki, A.; Gazda, E.

1986-01-01

The construction of primary ion source for SIMS has been presented. The influence of individual operation parameters on the properties of ion source has been investigated. Optimization of these parameters has allowed to appreciate usefulness of the ion source for SIMS study. 14 refs., 8 figs., 2 tabs. (author)

Copper hazards to fish, wildlife and invertebrates: a synoptic review

Science.gov (United States)

Eisler, Ronald

1998-01-01

Selective review and synthesis of the technical literature on copper and copper salts in the environment and their effects primarily on fishes, birds, mammals, terrestrial and aquatic invertebrates, and other natural resources. The subtopics include copper sources and uses; chemical and biochemical properties; concentrations of copper in field collections of abiotic materials and living organisms; effects of copper deficiency; lethal and sublethal effects on terrestrial plants and invertebrates, aquatic organisms, birds and mammals, including effects on survival, growth, reproduction, behavior, metabolism, carcinogenicity, matagenicity, and teratogenicity; proposed criteria for the protection of human health and sensitive natural resources; and recommendations for additional research.

Anaerobic Copper Toxicity and Iron-Sulfur Cluster Biogenesis in Escherichia coli.

Science.gov (United States)

Tan, Guoqiang; Yang, Jing; Li, Tang; Zhao, Jin; Sun, Shujuan; Li, Xiaokang; Lin, Chuxian; Li, Jianghui; Zhou, Huaibin; Lyu, Jianxin; Ding, Huangen

2017-08-15

While copper is an essential trace element in biology, pollution of groundwater from copper has become a threat to all living organisms. Cellular mechanisms underlying copper toxicity, however, are still not fully understood. Previous studies have shown that iron-sulfur proteins are among the primary targets of copper toxicity in Escherichia coli under aerobic conditions. Here, we report that, under anaerobic conditions, iron-sulfur proteins in E. coli cells are even more susceptible to copper in medium. Whereas addition of 0.2 mM copper(II) chloride to LB (Luria-Bertani) medium has very little or no effect on iron-sulfur proteins in wild-type E. coli cells under aerobic conditions, the same copper treatment largely inactivates iron-sulfur proteins by blocking iron-sulfur cluster biogenesis in the cells under anaerobic conditions. Importantly, proteins that do not have iron-sulfur clusters (e.g., fumarase C and cysteine desulfurase) in E. coli cells are not significantly affected by copper treatment under aerobic or anaerobic conditions, indicating that copper may specifically target iron-sulfur proteins in cells. Additional studies revealed that E. coli cells accumulate more intracellular copper under anaerobic conditions than under aerobic conditions and that the elevated copper content binds to the iron-sulfur cluster assembly proteins IscU and IscA, which effectively inhibits iron-sulfur cluster biogenesis. The results suggest that the copper-mediated inhibition of iron-sulfur proteins does not require oxygen and that iron-sulfur cluster biogenesis is the primary target of anaerobic copper toxicity in cells. IMPORTANCE Copper contamination in groundwater has become a threat to all living organisms. However, cellular mechanisms underlying copper toxicity have not been fully understood up to now. The work described here reveals that iron-sulfur proteins in Escherichia coli cells are much more susceptible to copper in medium under anaerobic conditions than they

Metal lost and found: dissipative uses and releases of copper in the United States 1975-2000.

Science.gov (United States)

Lifset, Reid J; Eckelman, Matthew J; Harper, E M; Hausfather, Zeke; Urbina, Gonzalo

2012-02-15

Metals are used in a variety of ways, many of which lead to dissipative releases to the environment. Such releases are relevant from both a resource use and an environmental impact perspective. We present a historical analysis of copper dissipative releases in the United States from 1975 to 2000. We situate all dissipative releases in copper's life cycle and introduce a conceptual framework by which copper dissipative releases may be categorized in terms of intentionality of use and release. We interpret our results in the context of larger trends in production and consumption and government policies that have served as drivers of intentional copper releases from the relevant sources. Intentional copper releases are found to be both significant in quantity and highly variable. In 1975, for example, the largest source of intentional releases was from the application of copper-based pesticides, and this decreased more than 50% over the next 25 years; all other sources of intentional releases increased during that period. Overall, intentional copper releases decreased by approximately 15% from 1975 to 2000. Intentional uses that are unintentionally released such as copper from roofing, increased by the same percentage. Trace contaminant sources such as fossil fuel combustion, i.e., sources where both the use and the release are unintended, increased by nearly 50%. Intentional dissipative uses are equivalent to 60% of unintentional copper dissipative releases and more than five times that from trace sources. Dissipative copper releases are revealed to be modest when compared to bulk copper flows in the economy, and we introduce a metric, the dissipation index, which may be considered an economy-wide measure of resource efficiency for a particular substance. We assess the importance of dissipative releases in the calculation of recycling rates, concluding that the inclusion of dissipation in recycling rate calculations has a small, but discernible, influence, and should

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).

Preparation and structure of carbon encapsulated copper nanoparticles

International Nuclear Information System (INIS)

Hao Chuncheng; Xiao Feng; Cui Zuolin

2008-01-01

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

Effect of physicochemical form on copper availability to aquatic organisms

International Nuclear Information System (INIS)

Harrison, F.L.

1983-11-01

Copper concentration and speciation were determined in influent and effluent waters collected from eight power stations that used copper alloys in their cooling systems. Quantities of copper associated with particles, colloids, and organic and inorganic ligands differed with the site, season, and mode of operation of the station. Under normal operating conditions, the differences between influent and effluent waters were generally small, and most of the copper was in bound (complexed) species. However, copper was high in concentration and present in labile species during start-up of water circulation through some cooling systems and during changeover from an open- to closed-cycle operation. Copper sensitivity of selected ecologically and economically important aquatic organisms was also evaluted. Our primary emphasis was on acute effects and most of the testing was performed under controlled laboratory conditions. However, sublethal effects of copper on a population of bluegills living in a power station cooling lake containing water of low pH were also assessed. The toxic response to copper differed with the species and life stage of the animal and with the chemical form of copper in the water

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

Development of the Dutch primary standard for beta-emitting brachytherapy sources

International Nuclear Information System (INIS)

Marel, J. an der; Dijk, E. van

2002-01-01

The application of β-radiation emitting radioactive sources in medicine is rapidly expanding. An important new application is the use of β-radiation emitting radioactive sources in endovascular brachytherapy to avoid restenosis. Another well-known application is the use of the ophthalmic applicator (flat or concave surface source) for the treatment of tumors in the eye. Dose and dose distributions are very important characteristics of brachytherapy sources. The absorbed dose in the treated tissue should be known accurately to assure a good quality of the treatment and to develop new treatment methods and source configurations. At the Nederland s Meetinstituut (NMi) a project is going on for the development of a primary standard for betadosimetry. With this standard, dose and dose distributions of β-sources as used in brachytherapy can be measured in terms of absorbed dose to water. The primary standard is based on an extrapolation chamber. The extrapolation chamber will become part of a quality assurance system in Dutch hospitals for endovascular brachytherapy sources. The quality assurance system will further consist of transfer standards like well-type ionisation chambers, plastic scintillator systems and radiochromic film dosimetry. Apart from the endovascular sources the extrapolation chamber will be used to characterize ophthalmic applicators

Hydrogen Production Costs of Various Primary Energy Sources

International Nuclear Information System (INIS)

Choi, Jae Hyuk; Tak, Nam Il; Kim, Yong Hee; Park, Won Seok

2005-11-01

Many studies on the economical aspects of hydrogen energy technologies have been conducted with the increase of the technical and socioeconomic importance of the hydrogen energy. However, there is still no research which evaluates the economy of hydrogen production from the primary energy sources in consideration of Korean situations. In this study, the hydrogen production costs of major primary energy sources are compared in consideration of the Korean situations such as feedstock price, electricity rate, and load factor. The evaluation methodology is based on the report of the National Academy of Science (NAS) of U.S. The present study focuses on the possible future technology scenario defined by NAS. The scenario assumes technological improvement that may be achieved if present research and development (R and D) programs are successful. The production costs by the coal and natural gas are 1.1 $/kgH 2 and 1.36 $/kgH 2 , respectively. However, the fossil fuels are susceptible to the price variation depending on the oil and the raw material prices, and the hydrogen production cost also depends on the carbon tax. The economic competitiveness of the renewable energy sources such as the wind, solar, and biomass are relatively low when compared with that of the other energy sources. The estimated hydrogen production costs from the renewable energy sources range from 2.35 $/kgH 2 to 6.03 $/kgH 2 . On the other hand, the production cost by nuclear energy is lower than that of natural gas or coal when the prices of the oil and soft coal are above $50/barrel and 138 $/ton, respectively. Taking into consideration the recent rapid increase of the oil and soft coal prices and the limited fossil resource, the nuclear-hydrogen option appears to be the most economical way in the future

The Challenges of Primary Sources, Collaboration, and the K-16 Elizabeth Murray Project

Science.gov (United States)

Cleary, Patricia; Neumann, David

2009-01-01

In recent years, the use of primary sources in the history and social studies classroom has been increasingly promoted as a necessary and welcome practice, one designed to improve the quality of history education and to encourage student interest and engagement. Although some K-12 educators have been wary of adopting the use of primary sources,…

Biovailability of copper and zinc in pig and cattle slurries

NARCIS (Netherlands)

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

2013-01-01

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

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

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.

Hereditary iron and copper deposition

DEFF Research Database (Denmark)

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

2007-01-01

Hereditary deposition of iron (primary haemochromatosis) or copper (Wilson's disease) are autosomal recessive metabolic disease characterized by progressive liver pathology and subsequent involvement of various other organs. The prevalence of primary haemochromatosis is approximately 0.5%, about......, they may be inadequate in patients diagnosed so late that extensive body deposits of metal have been developed. The main research needs in this field are to further clarify molecular mechanisms of disease progression and to develop new chelators that are more effective and less toxic than those presently...

Crystal structures of E. coli laccase CueO at different copper concentrations

International Nuclear Information System (INIS)

Li Xu; Wei Zhiyi; Zhang Min; Peng Xiaohui; Yu Guangzhe; Teng Maikun; Gong Weimin

2007-01-01

CueO protein is a hypothetical bacterial laccase and a good laccase candidate for large scale industrial application. Four CueO crystal structures were determined at different copper concentrations. Low copper occupancy in apo-CueO and slow copper reconstitution process in CueO with exogenous copper were demonstrated. These observations well explain the copper dependence of CueO oxidase activity. Structural comparison between CueO and other three fungal laccase proteins indicates that Glu106 in CueO constitutes the primary counter-work for reconstitution of the trinuclear copper site. Mutation of Glu106 to a Phe enhanced CueO oxidation activity and supported this hypothesis. In addition, an extra α-helix from Leu351 to Gly378 covers substrate biding pocket of CueO and might compromises the electron transfer from substrate to type I copper

Eyewitness Culture and History: Primary Written Sources. The Iconoclast.

Science.gov (United States)

McMurtry, John

1995-01-01

Asserts that contemporary history and historiography is "official" history that ignores the daily struggles of people for their continued survival. Argues that, while public illiteracy has nearly disappeared, individuals are ignorant of the wealth of primary-source materials of other cultures' histories. (CFR)

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.

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.

Production of Copper as a Complex Mining and Metallurgical Processing System in Polish Copper Mines of the Legnica-Glogów Copper Belt

Science.gov (United States)

Malewski, Jerzy

2017-12-01

Geological and technological conditions of Cu production in the Polish copper mines of the Legnica-Glogów Copper Belt are presented. Cu production is recognized as a technological fractal consisting of subsystems for mineral exploration, ore extraction and processing, and metallurgical treatment. Qualitative and quantitative models of these operations have been proposed, including estimation of their costs of process production. Numerical calculations of such a system have been performed, which allow optimize the system parameters according to economic criteria under variable Cu mineralization in the ore deposit. The main objective of the study is to develop forecasting tool for analysis of production efficiency in domestic copper mines based on available sources of information. Such analyses are primarily of social value, allowing for assessment of the efficiency of management of local mineral resources in the light of current technological and market constraints. At the same time, this is a concept of the system analysis method to manage deposit exploitation on operational and strategic level.

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.

Primary calibration of coiled 103Pd brachytherapy sources

International Nuclear Information System (INIS)

Paxton, Adam B.; Culberson, Wesley S.; DeWerd, Larry A.; Micka, John A.

2008-01-01

Coiled 103 Pd brachytherapy sources have been developed by RadioMed Corporation for use as low-dose-rate (LDR) interstitial implants. The coiled sources are provided in integer lengths from 1 to 6 cm and address many common issues seen with traditional LDR brachytherapy sources. The current standard for determining the air-kerma strength (S K ) of low-energy LDR brachytherapy sources is the National Institute of Standards and Technology's Wide-Angle Free-Air Chamber (NIST WAFAC). Due to geometric limitations, however, the NIST WAFAC is unable to determine the S K of sources longer than 1 cm. This project utilized the University of Wisconsin's Variable-Aperture Free-Air Chamber (UW VAFAC) to determine the S K of the longer coiled sources. The UW VAFAC has shown agreement in S K values of 1 cm length coils to within 1% of those determined with the NIST WAFAC, but the UW VAFAC does not share the same geometric limitations as the NIST WAFAC. A new source holder was constructed to hold the coiled sources in place during measurements with the UW VAFAC. Correction factors for the increased length of the sources have been determined and applied to the measurements. Using the new source holder and corrections, the S K of 3 and 6 cm coiled sources has been determined. Corrected UW VAFAC data and ionization current measurements from well chambers have been used to determine calibration coefficients for use in the measurement of 3 and 6 cm coiled sources in well chambers. Thus, the UW VAFAC has provided the first transferable, primary measurement of low-energy LDR brachytherapy sources with lengths greater than 1 cm

Remediation of copper in vineyards – A mini review

International Nuclear Information System (INIS)

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

2012-01-01

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

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.

Primary Sources of Corporate Investment in Hungary

Directory of Open Access Journals (Sweden)

Katona Klára

2017-06-01

Full Text Available This research aims to reveal how Hungarian companies have financed investments over the last two decades. Which financing strategy characterized them: was internal capital accumulation or external resources, such as bank loans or foreign capital the primary source of corporate investments? The study gives an overview of the conditions typical in the Hungarian financing and capital market over the last 25 years through an empirical analysis. Using a linear regression model, the paper examines the main investments sources among the top 5000 Hungarian firms according to revenues between 1996 and 2014. The model proved that the effect of loans in financing investments was significant and positive in all examined firms, independently from their ownership in the whole period. The rate of indebtedness of foreign companies was mainly attributable to local bank credits and not loans granted by mother companies.

76 FR 17548 - Prevention of Significant Deterioration (PSD) and Nonattainment New Source Review (NSR...

Science.gov (United States)

2011-03-30

...; (vi) Primary aluminum ore reduction plants; (vii) Primary copper smelters; (viii) Municipal... acid plants; (x) Petroleum refineries; (xi) Lime plants; (xii) Phosphate rock processing plants; (xiii... smelters; (e) Iron and steel mills; (f) Primary aluminum ore reduction plants; (g) Primary copper smelters...

Effects of light and copper ions on volatile aldehydes of milk and milk fractions

Energy Technology Data Exchange (ETDEWEB)

Jeno, W.; Bassette, R.; Crang, R.E.

1988-09-01

Raw, laboratory-pasteurized and plant-pasteurized homogenized milks were exposed to copper ions (5 ppm), to sunlight or fluorescent light and the effects determined on the composition of volatile aldehydes. The greatest change due to copper treatment was an increase in n-hexanal; acetaldehyde showed the least response in each of the sources of milk. The responses were similar from all three sources of milk with laboratory-pasteurized milk samples showing the greatest responses for each aldehyde analyzed. Similar milk samples exposed to sunlight also showed an increase in volatile aldehydes from all milk sources but with the greatest response being acetaldehyde and n-pentanal components. The milk fraction most susceptible to changes in the presence of light was neutralized whey, whereas resuspended cream was most susceptible to copper exposure. Overall, dialyzed whey appeared to be influenced more than other milk fractions by both light and copper ions.

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.

Recovery of Copper from Slow Cooled Ausmelt Furnace Slag by Floatation

Science.gov (United States)

Xue, Ping; Li, Guangqiang; Qin, Qingwei

Ausmelt furnace slag contains about 0.9% Cu (mass %). With increasing the amount of Ausmelt furnace slag, the recovery of copper from it will produce an enormous economic yield. The recovery of copper by floatation from slow cooled Ausmelt furnace slag was studied in this paper. The phases and composition of the slow cooled slag were analyzed. The factors which affected the copper recovery efficiency such as grinding fineness, pH value of flotation medium, different collectors and floating process were investigated. It was shown that the size distribution of the primary grinding and secondary grinding of middling were 75% for particles less than 0.074mm and 82% for particles less than 0.043mm respectively. The closed-circuit experimental results with butyl xanthate as collector in laboratory showed that the copper grade reached 16.11% and the recovery rate of copper reached 69.90% and the copper grade of tailings was only 0.2%.

Recycled water sources influence the bioavailability of copper to earthworms.

Science.gov (United States)

Kunhikrishnan, Anitha; Bolan, Nanthi S; Naidu, Ravi; Kim, Won-Il

2013-10-15

Re-use of wastewaters can overcome shortfalls in irrigation demand and mitigate environmental pollution. However, in an untreated or partially treated state, these water sources can introduce inorganic contaminants, including heavy metals, to soils that are irrigated. In this study, earthworms (Eisenia fetida) have been used to determine copper (Cu) bioavailability in two contrasting soils irrigated with farm dairy, piggery and winery effluents. Soils spiked with varying levels of Cu (0-1,000 mg/kg) were subsequently irrigated with recycled waters and Milli-Q (MQ) water and Cu bioavailability to earthworms determined by mortality and avoidance tests. Earthworms clearly avoided high Cu soils and the effect was more pronounced in the absence than presence of recycled water irrigation. At the highest Cu concentration (1,000 mg/kg), worm mortality was 100% when irrigated with MQ-water; however, when irrigated with recycled waters, mortality decreased by 30%. Accumulation of Cu in earthworms was significantly less in the presence of recycled water and was dependent on CaCl2-extractable free Cu(2+) concentration in the soil. Here, it is evident that organic carbon in recycled waters was effective in decreasing the toxic effects of Cu on earthworms, indicating that the metal-organic complexes decreased Cu bioavailability to earthworms. Copyright © 2012 Elsevier B.V. All rights reserved.

[Use of copper oxide wire particles (Copinox) for the prevention of congenital copper deficiency in a herd of German Improved Fawn breed of goat].

Science.gov (United States)

Winter, P; Hochsteiner, W; Chizzola, R

2004-10-01

In a herd of German Improved Fawn breed of goat in the year 2000 neonatal kid losses due to congenital copper deficiencies were observed. To clarify the problems and to prevent losses in the next breeding season serum copper levels of 10 dams and four control Boer goats were investigated at four time points during one year. Additionally ten kids of the following year were sampled and the serum copper levels were studied. Immediatly after parturition and 8 weeks later the dams showed low serum copper levels (10.4 +/- 11.1 micromol/l, 5.7 +/- 2.9 micromol/l resp.). At the end of the pasture season an increase of serum copper could be measured (19.3 +/- 16.0 micromol/l). To prevent enzootic ataxia due to congenital copper deficiency, the dams were treated with copper oxide wire particles in the next late gestation. At this time point serum copper concentrations started to decrease (18.5 +/- 8.4 micromol/l). The re-examination 3 month later demonstrated an increase of the serum mean copper concentrations up to 23.4 micromol/l in the dams and to 16.2 micromol/l in the kids. The serum copper levels were significantly higher compared to the levels the year before. Big variation of the serum copper levels in the control Boer goats occurred during the year, but no clinical symptoms of copper deficiency could be observed. The copper levels in the grass and soil samples were 6.8 mg/kg and 0.2 mg/kg dry substance, respectively. A secondary copper deficiency based on cadmium could be excluded through the low levels of soil samples. The contents of sulphur and molybdenum were not determined. The results indicate that the German Improved Fawn breed of goats suffered from a primary copper deficiency due to the inefficient mineral supplementation. The administration of Copinox in the last third of the gestation leads to a continious raising of the copper concentrations in the serum and is suited to prevent ataxia due to congential copper deficiency in neonatal kids.

Fabrication of ion source components by electroforming

International Nuclear Information System (INIS)

Schechter, D.E.; Sluss, F.

1983-01-01

Several components of the Oak Ridge National Laboratory (ORNL)/Magnetic Fusion Test Facility (MFTF-B) ion source have been fabricated utilizing an electroforming process. A procedure has been developed for enclosing coolant passages in copper components by electrodepositing a thick (greater than or equal to 0.75-mm) layer of copper (electroforming) over the top of grooves machined into the copper component base. Details of the procedure to fabricate acceleration grids and other ion source components are presented

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

18 CFR 2.400 - Statement of interpretation of waste concerning natural gas as the primary energy source for...

Science.gov (United States)

2010-04-01

... interpretation of waste concerning natural gas as the primary energy source for qualifying small power production... concerning natural gas as the primary energy source for qualifying small power production facilities. For purposes of deciding whether natural gas may be considered as waste as the primary energy source pursuant...

Potential for improved extraction of tellurium as a byproduct of current copper mining processes

Science.gov (United States)

Hayes, S. M.; Spaleta, K. J.; Skidmore, A. E.

2016-12-01

Tellurium (Te) is classified as a critical element due to its increasing use in high technology applications, low average crustal abundance (3 μg kg-1), and primary source as a byproduct of copper extraction. Although Te can be readily recovered from copper processing, previous studies have estimated a 4 percent extraction efficiency, and few studies have addressed Te behavior during the entire copper extraction process. The goals of the present study are to perform a mass balance examining Te behavior during copper extraction and to connect these observations with mineralogy of Te-bearing phases which are essential first steps in devising ways to optimize Te recovery. Our preliminary mass balance results indicate that less than 3 percent of Te present in copper ore is recovered, with particularly high losses during initial concentration of copper ore minerals by flotation. Tellurium is present in the ore in telluride minerals (e.g., Bi-Te-S phases, altaite, and Ag-S-Se-Te phases identified using electron microprobe) with limited substitution into sulfide minerals (possibly 10 mg kg-1 Te in bulk pyrite and chalcopyrite). This work has also identified Te accumulation in solid-phase intermediate extraction products that could be further processed to recover Te, including smelter dusts (158 mg kg-1) and pressed anode slimes (2.7 percent by mass). In both the smelter dusts and anode slimes, X-ray absorption spectroscopy indicates that about two thirds of the Te is present as reduced tellurides. In anode slimes, electron microscopy shows that the remaining Te is present in an oxidized form in a complex Te-bearing oxidate phase also containing Pb, Cu, Ag, As, Sb, and S. These results clearly indicate that more efficient, increased recovery of Te may be possible, likely at minimal expense from operating copper processing operations, thereby providing more Te for manufacturing of products such as inexpensive high-efficiency solar panels.

Source contributions and regional transport of primary particulate matter in China.

Science.gov (United States)

Hu, Jianlin; Wu, Li; Zheng, Bo; Zhang, Qiang; He, Kebin; Chang, Qing; Li, Xinghua; Yang, Fumo; Ying, Qi; Zhang, Hongliang

2015-12-01

A source-oriented CMAQ was applied to determine source sector/region contributions to primary particulate matter (PPM) in China. Four months were simulated with emissions grouped to eight regions and six sectors. Predicted elemental carbon (EC), primary organic carbon (POC), and PPM concentrations and source contributions agree with measurements and have significant spatiotemporal variations. Residential is a major contributor to spring/winter EC (50-80%), POC (60%-90%), and PPM (30-70%). For summer/fall, industrial contributes 30-50% for EC/POC and 40-60% for PPM. Transportation is more important for EC (20-30%) than POC/PPM (Guangzhou and Chongqing. Dust contributes to 1/3-1/2 in spring/fall of Beijing, Xi'an and Chongqing. Based on sector-region combination, local residential/transportation and residential/industrial from Heibei are major contributors to spring PPM in Beijing. In summer/fall, local industrial is the largest. In winter, residential/industrial from local and Hebei account for >90% in Beijing. Copyright © 2015 Elsevier Ltd. All rights reserved.

Implementing Open Source Platform for Education Quality Enhancement in Primary Education: Indonesia Experience

Science.gov (United States)

Kisworo, Marsudi Wahyu

2016-01-01

Information and Communication Technology (ICT)-supported learning using free and open source platform draws little attention as open source initiatives were focused in secondary or tertiary educations. This study investigates possibilities of ICT-supported learning using open source platform for primary educations. The data of this study is taken…

Optimization of chemical displacement deposition of copper on porous silicon.

Science.gov (United States)

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

2012-11-01

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

Surface properties of copper based cermet materials

International Nuclear Information System (INIS)

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

2008-01-01

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

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.

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.

Copper accumulation by stickleback nests containing spiggin.

Science.gov (United States)

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

2016-07-01

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

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.

Modification of medical metals by ion implantation of copper

Science.gov (United States)

Wan, Y. Z.; Xiong, G. Y.; Liang, H.; Raman, S.; He, F.; Huang, Y.

2007-10-01

The effect of copper ion implantation on the antibacterial activity, wear performance and corrosion resistance of medical metals including 317 L of stainless steels, pure titanium, and Ti-Al-Nb alloy was studied in this work. The specimens were implanted with copper ions using a MEVVA source ion implanter with ion doses ranging from 0.5 × 10 17 to 4 × 10 17 ions/cm 2 at an energy of 80 keV. The antibacterial effect, wear rate, and inflexion potential were measured as a function of ion dose. The results obtained indicate that copper ion implantation improves the antibacterial effect and wear behaviour for all the three medical materials studied. However, corrosion resistance decreases after ion implantation of copper. Experimental results indicate that the antibacterial property and corrosion resistance should be balanced for medical titanium materials. The marked deteriorated corrosion resistance of 317 L suggests that copper implantation may not be an effective method of improving its antibacterial activity.

Identifying Marine Copper-Binding Ligands in Seawater

Science.gov (United States)

Whitby, H.; Hollibaugh, J. T.; Maldonado, M. T.; Ouchi, S.; van den Berg, S. M.

2016-02-01

Complexation reactions are important because they affect the bioavailability of trace metals such as copper and iron. For example, organic complexation can determine whether copper is a limiting or a toxic micronutrient at natural levels. Copper competes with iron for complexing ligands, and when iron is limiting, copper can also substitute for iron in some metabolic pathways. The speciation of copper can be measured using complexing capacity titrations, which provide the concentration of individual ligand classes (L1, L2 etc.) and the complex stabilities (log K). Using methods recently developed in our laboratory, we show that the ligands within these classes can be measured independently of titrations, thus confirming the titration method and simultaneously identifying the ligands within each class. Thiols were identified as the L1 ligand class and humic compounds as the weaker L2 class in samples from coastal Georgia, USA, collected monthly from April to December. Log K values of the ligand complexes were consistent with values expected for thiols and humic substances. Recent results from culture studies and from samples collected along Line P, a coastal - oceanic transect in the HNLC region of the NE subarctic Pacific, will be presented in comparison to the estuarine results. This comparison will help to broaden our perspective on copper complexation and the ligands responsible, furthering our understanding of ligand sources and life cycles.

Design study of primary ion provider for relativistic heavy ion collider electron beam ion source.

Science.gov (United States)

Kondo, K; Kanesue, T; Tamura, J; Okamura, M

2010-02-01

Brookhaven National Laboratory has developed the new preinjector system, electron beam ion source (EBIS) for relativistic heavy ion collider (RHIC) and National Aeronautics and Space Administration Space Radiation Laboratory. Design of primary ion provider is an essential problem since it is required to supply beams with different ion species to multiple users simultaneously. The laser ion source with a defocused laser can provide a low charge state and low emittance ion beam, and is a candidate for the primary ion source for RHIC-EBIS. We show a suitable design with appropriate drift length and solenoid, which helps to keep sufficient total charge number with longer pulse length. The whole design of primary ion source, as well as optics arrangement, solid targets configuration and heating about target, is presented.

ORIGINAL ARTICLE PICTORIAL INTERLUDE The copper-beaten ...

African Journals Online (AJOL)

Variations and abnormalities of skull appearance and shape are often related to a primary maldevelopment of the brain.1 The copper-beaten skull appearance is typically associated with craniosynostosis, which is the premature fusion of the cranial bone sutures (Fig. 2).2 Severe craniosynostosis and reduced cranial ...

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-beryllium alloys for technical applications

International Nuclear Information System (INIS)

Heller, W.

1976-01-01

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

Art of Wrought Copper in Turkey

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Nuran KAYABAŞI

2014-07-01

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

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.)

A solidification/stabilization process for wastewater treatment sludge from a primary copper smelter

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Ivšić-Bajčeta Dragana

2013-01-01

Full Text Available Wastewater treatment sludge from primary copper smelter is characterized as hazardous waste that requires treatment prior disposal due to significant amount of heavy metals and arsenic. The aim of the presented study was to investigate the feasibility and the effectiveness of solidification/stabilization process of the sludge using fly ash and lime as binders. The effectiveness of the process was evaluated by Unconfined Compressive Strength (UCS testing, leaching tests (EN 12457-4 and Toxicity Characteristic Leaching Procedure (TCLP and Acid Neutralization Capacity (ANC test. All samples reached target UCS of 0.35 MPa. Calcium to silicon concentration ratio (cCa/cSi, determined by X-Ray Fluorescence (XRF analysis, was identified as main factor governing strength development. Inductively coupled plasma-optical emission spectrometry (ICP-OES analyses of solutions after leaching tests showed excellent stabilization of Cu, Ni, Pb and Zn (above 99 % and arsenic (above 90 % in samples with high Ca(OH2 content. Results of ANC test indicated that buffering capacity of solidified material linearly depended on Ca concentration in FA and lime. Sample with 20 % of binder heaving 50 % of FA and 50 % of lime met all requirements to be safely disposed. [Projekat Ministarstva nauke Republike Srbije, br. 34033

Hydrogen Production Costs of Various Primary Energy Sources

International Nuclear Information System (INIS)

Choi, Jae Hyuk; Tak, Nam Il; Kim, Yong Hee; Park, Won Seok

2005-01-01

The limited resource and environmental impacts of fossil fuels are becoming more and more serious problems in the world. Consequently, hydrogen is in the limelight as a future alternative energy due to its clean combustion and inexhaustibility and a transition from the traditional fossil fuel system to a hydrogen-based energy system is under considerations. Several countries are already gearing the industries to the hydrogen economy to cope with the limitations of the current fossil fuels. Unfortunately, hydrogen has to be chemically separated from the hydrogen compounds in nature such as water by using some energy sources. In this paper, the hydrogen production costs of major primary energy sources are compared in consideration of the Korean situations. The evaluation methodology is based on the report of the National Academy of Science (NAS) of U.S

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).

Phosphoramidite accelerated copper(I)-catalyzed [3+2] cycloadditions of azides and alkynes

NARCIS (Netherlands)

Campbell-Verduyn, Lachlan S.; Mirfeizi, Leila; Dierckx, Rudi A.; Elsinga, Philip H.; Feringa, Ben L.

2009-01-01

Monodentate phosphoramidite ligands are used to accelerate the copper(I)-catalyzed 1,3-dipolar cycloaddition of azides and alkynes (CuAAC) rapidly yielding a wide variety of functionalized 1,4-disubstituted-1,2,3-triazoles; Cu(I) and Cu(II) salts both function as the copper source in aqueous

Identification of the sources of primary organic aerosols at urban schools: A molecular marker approach

International Nuclear Information System (INIS)

Crilley, Leigh R.; Qadir, Raeed M.; Ayoko, Godwin A.; Schnelle-Kreis, Jürgen; Abbaszade, Gülcin; Orasche, Jürgen; Zimmermann, Ralf; Morawska, Lidia

2014-01-01

Children are particularly susceptible to air pollution and schools are examples of urban microenvironments that can account for a large portion of children's exposure to airborne particles. Thus this paper aimed to determine the sources of primary airborne particles that children are exposed to at school by analyzing selected organic molecular markers at 11 urban schools in Brisbane, Australia. Positive matrix factorization analysis identified four sources at the schools: vehicle emissions, biomass burning, meat cooking and plant wax emissions accounting for 45%, 29%, 16% and 7%, of the organic carbon respectively. Biomass burning peaked in winter due to prescribed burning of bushland around Brisbane. Overall, the results indicated that both local (traffic) and regional (biomass burning) sources of primary organic aerosols influence the levels of ambient particles that children are exposed at the schools. These results have implications for potential control strategies for mitigating exposure at schools. - Highlights: • Selected organic molecular markers at 11 urban schools were analyzed. • Four sources of primary organic aerosols were identified by PMF at the schools. • Both local and regional sources were found to influence exposure at the schools. • The results have implications for mitigation of children's exposure at schools. - The identification of the most important sources of primary organic aerosols at urban schools has implications for control strategies for mitigating children's exposure at schools

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.

Direct and indirect effects of copper-contaminated sediments on the functions of model freshwater ecosystems.

Science.gov (United States)

Gardham, Stephanie; Chariton, Anthony A; Hose, Grant C

2015-01-01

Copper is acutely toxic to, and directly affects, primary producers and decomposers, which are key players in essential processes such as the nutrient cycle in freshwater ecosystems. Even though the indirect effects of metals (for example effects due to changes in species interactions) may be more common than direct effects, little is known about the indirect effects of copper on primary producers and decomposers. The effects of copper on phytoplankton, macrophytes, periphyton and organic matter decomposition in an outdoor lentic mesocosm facility were assessed, and links between the responses examined. Copper directly decreased macrophyte growth, subsurface organic matter decomposition, and the potential for high phytoplankton Chlorophyll a concentrations. However, periphyton cover and organic matter decomposition on the surface of the sediment were stimulated by the presence of copper. These latter responses were attributed to indirect effects, due to a reduction in grazing pressure from snails, particularly Physa acuta, in the higher copper-contaminated mesocosms. This permitted the growth of periphyton and other heterotrophs, ultimately increasing decomposition at the sediment surface. The present study demonstrates the pronounced influence indirect effects may have on ecological function, findings that may not be observed in traditional laboratory studies (which utilize single species or simplistic communities).

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.

Safety Analysis Report for Primary Capsule of Ir-192 Radiation Source

International Nuclear Information System (INIS)

Lee, J. C.; Bang, K. S.; Choi, W. S.; Seo, K. S.; Son, K. J.; Park, W. J.

2008-12-01

All of the source capsules to transport a special form radioactive material should be designed and fabricated in accordance with the design criteria prescribed in IAEA standards and domestic regulations. The objective of this project is to prove the safety of a primary capsule for Ir-192 radiation source which produced in the HANARO. The safety tests of primary capsules were carried out for the impact, percussion and heat conditions. And leakage tests were carried out before and after the each tests. The capsule showed slight scratches and their deformations were not found after each tests. It also met the allowable limits of leakage rate after each test. Therefore, it has been verified that the capsule was designed and fabricated to meet all requirements for the special form radioactive materials

Selective LPCVD growth of graphene on patterned copper and its growth mechanism

Science.gov (United States)

Zhang, M.; Huang, B.-C.; Wang, Y.; Woo, J. C. S.

2016-12-01

Copper-catalyzed graphene low-pressure chemical-vapor deposition (LPCVD) growth has been regarded as a viable solution towards its integration to CMOS technology, and the wafer-bonding method provides a reliable alternative for transferring the selective graphene grown on a patterned metal film for IC manufacturing. In this paper, selective LPCVD graphene growth using patterned copper dots has been studied. The Raman spectra of grown films have demonstrated large dependence on the growth conditions. To explain the results, the growth mechanisms based on surface adsorption and copper-vapor-assisted growth are investigated by the comparison between the blanket copper films with/without the additional copper source. The copper vapor density is found to be critical for high-quality graphene growth. In addition, the copper-vapor-assisted growth is also evidenced by the carbon deposition on the SiO2 substrate of the patterned-copper-dot sample and chamber wall during graphene growth. This growth mechanism explains the correlation between the growth condition and Raman spectrum for films on copper dots. The study on the copper-catalyzed selective graphene growth on the hard substrate paves the way for the synthesis and integration of the 2D material in VLSI.

Copper in household drinking water in the city of Zagreb, Croatia.

Science.gov (United States)

Pizent, Alica; Butković, Sanja

2010-09-01

Copper concentration was estimated in tap water samples obtained from 70 households in Zagreb, serviced by a public water supply system. First-draw and flushed samples of tap water were collected in the morning and total copper concentration was determined by graphite furnace atomic absorption spectrometry with Zeeman-effect background correction. We also estimated the contribution of plumbing material to copper concentrations in tap water. In households with copper pipes, median and range copper values were 310 μg L-1 [(27 to 632) μg L-1] in first-draw samples and 16 μg L-1 [(5 to 52) μg L-1] in flushed samples. Corresponding values for households with galvanised pipes were 140 μg L-1 [(11 to 289) μg L-1] and 8 μg L-1 [(1 to 42) μg L-1], respectively. Copper concentrations in household tap water in Zagreb were far below the proposed safe limits set by the Croatian and WHO regulations and EPA standards, and drinking water in Zagreb is not a significant source of copper exposure.

Primary Sources. Update: Teachers' Views on Common Core State Standards

Science.gov (United States)

Scholastic Inc. and the Bill & Melinda Gates Foundation, 2014

2014-01-01

Scholastic and the Bill & Melinda Gates Foundation fielded the third edition of the "Primary Sources" survey of America's teachers in July 2013 (see ED562664). Twenty thousand pre-K through grade 12 public school teachers responded, sharing their perspectives on issues important to their profession, including the Common Core State…

Influence of copper on Euplotes sp. and associated bacterial population

Directory of Open Access Journals (Sweden)

Guilherme Oliveira Andrade da Silva

2014-05-01

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

Primary source of income is associated with differences in HIV risk behaviors in street-recruited samples.

Science.gov (United States)

Essien, E James; Ross, Michael W; Williams, Mark L; Meshack, Angela F; Fernández-Esquer, Maria E; Peters, Ronald J; Ogungbade, GO

2004-06-17

BACKGROUND: The relationship between primary source of income and HIV risk behaviors and the racial/ethnic differences in risk behavior profiles among disadvantaged populations have not been fully explored. This is unusual given that the phenomenon of higher risk in more disadvantaged populations is well-known but the mechanisms remain unclear. We examined the relationship between primary source of income and differences in HIV risk behaviors among four racial/ethnic groups in the southern United States. METHODS: Self-reported data on primary source of income and HIV risk behaviors were collected from 1494 African American, Hispanic, Asian, and White men and women in places of public congregation in Houston, Texas. Data were analyzed using calculation of percentages and by chi-square tests with Yates correction for discontinuity where appropriate. RESULTS: Data revealed that a higher proportion of whites were involved in sex for money exchanges compared to the other racial groups in this sample. The data suggest that similar street sampling approaches are likely to recruit different proportions of people by primary income source and by ethnicity. It may be that the study locations sampled are likely to preferentially attract those involved in illegal activities, specifically the white population involved in sex for drug or money exchanges. Research evidence has shown that people construct highly evolved sexual marketplaces that are localized and most unlikely to cross racial, ethnic, and socioeconomic or geographical boundaries. Thus, the areas that we sampled may have straddled a white sexual marketplace more than that of the other groups, leading to an over-representation of sex exchange in this group. Drug use was highest among those with illegal primary sources of income (sex exchange and drug dealing and theft), and they were also those most likely to have injected drugs rather than administered them by any other route (p primary source of income category. The

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 ...

A radiation hard dipole magnet coils using aluminum clad copper conductors

International Nuclear Information System (INIS)

Leonhardt, W.J.

1989-01-01

A C-type septum dipole magnet is located 600 mm downstream of the primary target in an external beam line of the AGS. Conventional use of fiber glass/epoxy electrical insulation for the magnet coils results in their failure after a relatively short running period, therefore a radiation hard insulation system is required. This is accomplished by replacing the existing copper conductor with a copper conductor having a thin aluminum skin which is anodized to provide the electrical insulation. Since the copper supports a current density of 59 A/mm 2 , no reduction in cross sectional area can be tolerated. Design considerations, manufacturing techniques, and operating experience of a prototype dipole is presented. 3 refs., 4 figs

Storing drinking-water in copper pots kills contaminating diarrhoeagenic bacteria.

Science.gov (United States)

Sudha, V B Preethi; Ganesan, Sheeba; Pazhani, G P; Ramamurthy, T; Nair, G B; Venkatasubramanian, Padma

2012-03-01

Microbially-unsafe water is still a major concern in most developing countries. Although many water-purification methods exist, these are expensive and beyond the reach of many people, especially in rural areas. Ayurveda recommends the use of copper for storing drinking-water. Therefore, the objective of this study was to evaluate the effect of copper pot on microbially-contaminated drinking-water. The antibacterial effect of copper pot against important diarrhoeagenic bacteria, including Vibrio cholerae O1, Shigella flexneri 2a, enterotoxigenic Escherichia coli, enteropathogenic E. coli, Salmonella enterica Typhi, and Salmonella Paratyphi is reported. When drinking-water (pH 7.83 +/- 0.4; source: ground) was contaminated with 500 CFU/mL of the above bacteria and stored in copper pots for 16 hours at room temperature, no bacteria could be recovered on the culture medium. Recovery failed even after resuscitation in enrichment broth, followed by plating on selective media, indicating loss of culturability. This is the first report on the effect of copper on S. flexneri 2a, enteropathogenic E. coli, and Salmonella Paratyphi. After 16 hours, there was a slight increase in the pH of water from 7.83 to 7.93 in the copper pots while the other physicochemical parameters remained unchanged. Copper content (177 +/- 16 ppb) in water stored in copper pots was well within the permissible limits of the World Health Organization. Copper holds promise as a point-of-use solution for microbial purification of drinking-water, especially in developing countries.

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

Stress Sources and Manifestations in a Nationwide Sample of Pre-Primary, Primary, and Secondary Educators in Greece.

Science.gov (United States)

Kourmousi, Ntina; Alexopoulos, Evangelos C

2016-01-01

Teachers experience high levels of stress as a result of their professional duties, and research has shown a growing interest in this phenomenon during the recent years. Aim of this study was to explore the associations of stress sources and manifestations with individual and job-related characteristics in educators of all levels. In a cross-sectional design, following an informative e-campaign on the study aims through the official and the main teachers' portals in Greece, respondents completed online the teachers stress inventory (TSI) and the 14-item Perceived Stress Scale. Nine hundred seventy-four male and 2473 female pre-primary, primary, and secondary educators with a mean age of 41.2 years responded. Women and younger teachers reported significantly higher levels of stress, mainly due to lack of time and other work-related stressors, and also more emotional and gastronomic manifestations. Increased age and working experience were associated with lower levels of several stress sources. Teachers of administrative positions had increased time management stressors, but less professional distress, professional investment, and discipline and motivation stressors. Additionally, working and residing far from family increased teachers' stress levels associated with control, motivation, and investment. Teachers of pre-primary education had reduced professional investment and motivation stress factors, while vocational lyceum teachers of secondary education reported less work-related stressors and manifestations and more discipline and motivation-related ones. Having students supported or in need of support from special educators and students with difficulties in speaking or comprehension was associated with most of the teachers' stress sources and manifestations (i.e., TSI subscales). Finally, colleagues' and mainly supervisors' support seemed to provide a strong and consistent protection against both stress sources and manifestations. Stress factors and

A Review of Evidence for Corrosion of Copper by water

Energy Technology Data Exchange (ETDEWEB)

Apted, Michael J. (Monitor Scientific LLC (United Kingdom)); Bennett, David G. (TerraSalus Limited (United Kingdom)); Saario, Timo (VTT Materials and Building (Finland))

2009-09-15

The planned spent nuclear fuel repository in Sweden relies on a copper cast iron canister as the primary engineered barrier. The corrosion behaviour of copper in the expected environment needs to be thoroughly understood as a basis for the post-closure safety analysis. It has been shown that corrosion may indeed be the primary canister degradation process during the utilised assessment period of 1 million years (this period is the longest time for which risk calculations will be needed according guidelines issued by the Swedish Radiation Safety Authority). Previous analysis work has been based on that copper is corroded during the initial oxic environment as well as by sulphide in groundwater once reducing conditions have been restored. The quantitative analyses of these processes consider upper-bound amounts of atmospheric oxidation as well as representative sulphide concentrations coupled with the transport limitation of the bentonite buffer and of the surrounding bedrock. A group of researchers at the Royal Institute of Technology (KTH), Stockholm, Sweden suggest, based on published experimental results, that disposed canisters will also be corroded by water itself under hydrogen evolution. The purpose of the project is to evaluate the findings of the KTH research group based on an assessment of their experimental methods and chemical analysis work, thermodynamic models, and a discussion of reaction mechanisms as well as comparison with the analogue behaviour of native copper. As a background, the authors also provide a brief overview of other corrosion processes and safety assessment significance. The authors conclude that the KTH researchers have not convincingly demonstrated that copper will indeed be corroded by pure water and that it is in any case very unlikely that this process will be dominant under the reducing chemical conditions that are expected in the repository environment. How-ever, the authors do not completely rule out that copper may corrode

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.

Laser-Induced, Local Oxidation of Copper Nanoparticle Films During Raman Measurements

Science.gov (United States)

Hight Walker, Angela R.; Cheng, Guangjun; Calizo, Irene

2011-03-01

The optical properties of gold and silver nanoparticles and their films have been thoroughly investigated as surface enhanced Raman scattering (SERS) substrates and chemical reaction promoters. Similar to gold and silver nanoparticles, copper nanoparticles exhibit distinct plasmon absorptions in the visible region. The work on copper nanoparticles and their films is limited due to their oxidization in air. However, their high reactivity actually provides an opportunity to exploit the laser-induced thermal effect and chemical reactions of these nanoparticles. Here, we present our investigation of the local oxidation of a copper nanoparticle film induced by a visible laser source during Raman spectroscopic measurements. The copper nanoparticle film is prepared by drop-casting chemically synthesized copper colloid onto silicon oxide/silicon substrate. The local oxidation induced by visible lasers in Raman spectroscopy is monitored with the distinct scattering peaks for copper oxides. Optical microscopy and scanning electron microscopy have been used to characterize the laser-induced morphological changes in the film. The results of this oxidation process with different excitation wavelengths and different laser powers will be presented.

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...

Kinetics of excited levels in copper-vapor laser

International Nuclear Information System (INIS)

Smilanski, I.

1981-10-01

A full and representative description of the excited copper level kinetics in a copper-vapor laser is presented. The research was carried out in three stages. The first stage was the development of a representative and reliable measurement cell. A laser tube constructed of refractory materials and an excitation circuit which provides short pulses at a high repetition rate to heat the tube and excite the copper atoms were developed. This stage was also dedicated to characterizing the laser and studying its scaling laws. In the second stage a rapid neasuring system which avoids the problem of spectral line shape was developed. The system is based on the 'hook' method, which utilizes the anomalous dispersion in the vicinity of an atomic line. The light source, a wide band nitrogen-laser-pumped dye laser, ensures a short sampling time, and the recording system, with a television camera face as the recording medium, allows precise data reduction. In the third stage the excited copper level kinetics in a copper vapor laser is measured. The principal conclusions, that only a small part of the energy in the discharge is utilized to populate the upper laser levels and that the lower laser level population is very large at the end of the excitation pulse and cannot be attributed to relaxation of the upper levels, necessitate a new kinetic description of the copper-vapor laser. The laser is not self-terminating; it is activated and terminated by the electrical discharge

Gas discharge ion source. I. Duoplasmatron

International Nuclear Information System (INIS)

Bacon, F.M.

1978-01-01

The effects of the plasma expansion cup on the operation of a duoplasmatron ion source have been investigated by measuring the total ion current and the distributions of the ion energy, mass, and current density. A copper expansion cup did not affect the magnetic field near the anode of the ion source and consequently the ion current density distribution was sharply peaked near the center of the cup. Ion energy distributions were approximately symmetrical about anode potential. The dominant ionic species were D + 3 and D + at low and high arc currents, respectively. Changes in the electrical potential of the copper cup with respect to the anode produced negligible changes in the above data. A mild steel plasma expansion cup caused the magnetic field to diverge and intercept the cup walls, resulting in ion current density distributions that were flatter and more amenable to focusing than the ones with the copper cup. With the steel cup at anode potential, the ion mass distribution was similar to that from the copper cup; however, the ion energy distribution was asymmetrical about the anode potential with a peak about 10-20 V above anode potential. The total ion current from this mode of operation was about one-third the value from the copper cup. If the steel cup assumed floating potential, about 50 V below anode potential, the total current increased to the level observed from the copper cup and the ion energy distribution was similar to that observed with the copper cup but the current density distribution was much flatter than that of the copper cup. The ion mass distribution was 60%-70% atomic ions over the entire arc current range investigated. Based on these data, a modified plasma expansion cup was designed with tapered steel walls lined with a boron nitride insert. The overall performance of the duoplasmatron ion source with this cup was superior to any of the previous three modes of operation

Energy deposition in a thin copper target downstream and off-axis of a proton-radiography target

International Nuclear Information System (INIS)

Greene, G.A.; Finfrock, C.C.; Snead, C.L.; Hanson, A.L.; Murray, M.M.

2002-01-01

A series of proton energy-deposition experiments was conducted to measure the energy deposited in a copper target located downstream and off-axis of a high-energy proton-radiography target. The proton/target interactions involved low-intensity bunches of protons at 24 GeV/c onto a spherical target consisting of concentric shells of tungsten and copper. The energy-deposition target was placed at five locations downstream of the proton-radiography target, off-axis of the primary beam transport, and was either unshielded or shielded by 5 or 10 cm of lead. Maximum temperature rises measured in the energy-deposition target due to single bunches of 5x10 10 protons on the proton-radiography target were approximately 20 mK per bunch. The data indicated that the scattered radiation was concentrated close to the primary transport axis of the beam line. The energy deposited in the energy-deposition target was reduced by moving the target radially away from the primary transport axis. Placing lead shielding in front of the target further reduced the energy deposition. The measured temperature rises of the energy-deposition target were empirically correlated with the distance from the source, the number of protons incident on the proton-radiography target, the thickness of the lead shielding, and the angle of the energy-deposition target off-axis of the beam line from the proton-radiography target. The correlation of the experimental data that was developed provides a starting point for the evaluation of the shielding requirements for devices downstream of proton-radiography targets such as superconducting magnets

Nickel, copper and cobalt coalescence in copper cliff converter slag

Directory of Open Access Journals (Sweden)

Wolf A.

2016-01-01

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

Primary sources of selected POPs: regional and global scale emission inventories

Energy Technology Data Exchange (ETDEWEB)

Breivik, Knut; Alcock, Ruth; Li Yifan; Bailey, Robert E.; Fiedler, Heidelore; Pacyna, Jozef M

2004-03-01

During the last decade, a number of studies have been devoted to the sources and emissions of Persistent Organic Pollutants (POPs) at regional and global scales. While significant improvements in knowledge have been achieved for some pesticides, the quantitative understanding of the emission processes and emission patterns for 'non-pesticide' POPs are still considered limited. The key issues remaining for the non-pesticide POPs are in part determined by their general source classification. For industrial chemicals, such as the polychlorinated biphenyls (PCBs), there is considerable uncertainty with respect to the relative importance of atmospheric emissions from various source categories. For PCBs, temperature is discussed as a potential key factor influencing atmospheric emission levels and patterns. When it comes to the unintentional by-products of combustion and industrial processes (PCDD/Fs), there is still a large uncertainty with respect to the relative contribution of emissions from unregulated sources such as backyard barrel burning that requires further consideration and characterisation. For hexachlorobenzene (HCB), the relative importance of primary and secondary atmospheric emissions in controlling current atmospheric concentrations remains one of the key uncertainties. While these and other issues may remain unresolved, knowledge concerning the emissions of POPs is a prerequisite for any attempt to understand and predict the distribution and fate of these chemicals on a regional and global scale as well as to efficiently minimise future environmental burdens. - Knowledge of primary emissions is a prerequisite for understanding and predicting POPs on a regional/global scale.

Primary sources of selected POPs: regional and global scale emission inventories

International Nuclear Information System (INIS)

Breivik, Knut; Alcock, Ruth; Li Yifan; Bailey, Robert E.; Fiedler, Heidelore; Pacyna, Jozef M.

2004-01-01

During the last decade, a number of studies have been devoted to the sources and emissions of Persistent Organic Pollutants (POPs) at regional and global scales. While significant improvements in knowledge have been achieved for some pesticides, the quantitative understanding of the emission processes and emission patterns for 'non-pesticide' POPs are still considered limited. The key issues remaining for the non-pesticide POPs are in part determined by their general source classification. For industrial chemicals, such as the polychlorinated biphenyls (PCBs), there is considerable uncertainty with respect to the relative importance of atmospheric emissions from various source categories. For PCBs, temperature is discussed as a potential key factor influencing atmospheric emission levels and patterns. When it comes to the unintentional by-products of combustion and industrial processes (PCDD/Fs), there is still a large uncertainty with respect to the relative contribution of emissions from unregulated sources such as backyard barrel burning that requires further consideration and characterisation. For hexachlorobenzene (HCB), the relative importance of primary and secondary atmospheric emissions in controlling current atmospheric concentrations remains one of the key uncertainties. While these and other issues may remain unresolved, knowledge concerning the emissions of POPs is a prerequisite for any attempt to understand and predict the distribution and fate of these chemicals on a regional and global scale as well as to efficiently minimise future environmental burdens. - Knowledge of primary emissions is a prerequisite for understanding and predicting POPs on a regional/global scale

Contamination of urban garden soils with copper and boron

Energy Technology Data Exchange (ETDEWEB)

Purves, D

1966-06-04

Spectrochemical analyses of garden soils sampled in the Edinburgh and Dundee areas indicate that there is substantial contamination of urban soils with copper and boron. These soils were analyzed spectrochemically with respect to total copper and water-extractable boron content with the view of comparing the levels obtained in urban areas with levels in arable soils in rural areas. The results indicate that urban garden soils contain about four times as much copper and two to three times as much water-soluble boron as rural arable soils. The existence of such a marked disparity between the levels of two potentially toxic elements in urban and rural areas is evidence of slow poisoning of the soil environment in built-up areas and is cause for concern. While the major source of contamination of soils with copper and boron is still a matter for speculation, it is probable that the addition of soot to garden soils and the fall-out of sooty material in built-up areas where atmospheric pollution is a problem make a substantial contribution to the water-extractable boron content of urban soils. Three samples of soot from domestic chimneys, obtained from independent sources, were found on analysis to contain 640, 650 and 555 p.p.m. water-extractable boron, and it is evident that the addition to soil of even small amounts of soot with a boron content of this order would have a marked effect on its water-extractable boron content.

Characterization of selenium in ambient aerosols and primary emission sources.

Science.gov (United States)

De Santiago, Arlette; Longo, Amelia F; Ingall, Ellery D; Diaz, Julia M; King, Laura E; Lai, Barry; Weber, Rodney J; Russell, Armistead G; Oakes, Michelle

2014-08-19

Atmospheric selenium (Se) in aerosols was investigated using X-ray absorption near-edge structure (XANES) spectroscopy and X-ray fluorescence (XRF) microscopy. These techniques were used to determine the oxidation state and elemental associations of Se in common primary emission sources and ambient aerosols collected from the greater Atlanta area. In the majority of ambient aerosol and primary emission source samples, the spectroscopic patterns as well as the absence of elemental correlations suggest Se is in an elemental, organic, or oxide form. XRF microscopy revealed numerous Se-rich particles, or hotspots, accounting on average for ∼16% of the total Se in ambient aerosols. Hotspots contained primarily Se(0)/Se(-II). However, larger, bulk spectroscopic characterizations revealed Se(IV) as the dominant oxidation state in ambient aerosol, followed by Se(0)/Se(-II) and Se(VI). Se(IV) was the only observed oxidation state in gasoline, diesel, and coal fly ash, while biomass burning contained a combination of Se(0)/Se(-II) and Se(IV). Although the majority of Se in aerosols was in the most toxic form, the Se concentration is well below the California Environmental Protection Agency chronic exposure limit (∼20000 ng/m(3)).

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....

Exploring the life cycle management of industrial solid waste in the case of copper slag.

Science.gov (United States)

Song, Xiaolong; Yang, Jianxin; Lu, Bin; Li, Bo

2013-06-01

Industrial solid waste has potential impacts on soil, water and air quality, as well as human health, during its whole life stages. A framework for the life cycle management of industrial solid waste, which integrates the source reduction process, is presented and applied to copper slag management. Three management scenarios of copper slag are developed: (i) production of cement after electric furnace treatment, (ii) production of cement after flotation, and (iii) source reduction before the recycling process. A life cycle assessment is carried out to estimate the environmental burdens of these three scenarios. Life cycle assessment results showed that the environmental burdens of the three scenarios are 2710.09, 2061.19 and 2145.02 Pt respectively. In consideration of the closed-loop recycling process, the environmental performance of the flotation approach excelled that of the electric furnace approach. Additionally, although flash smelting promotes the source reduction of copper slag compared with bath smelting, it did not reduce the overall environmental burdens resulting from the complete copper slag management process. Moreover, it led to the shifting of environmental burdens from ecosystem quality damage and resources depletion to human health damage. The case study shows that it is necessary to integrate the generation process into the whole life cycle of industrial solid waste, and to make an integrated assessment for quantifying the contribution of source reduction, rather than to simply follow the priority of source reduction and the hierarchy of waste management.

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.

Determination of copper in geological materials by X-ray fluorescence

International Nuclear Information System (INIS)

Roca, M.; Bayon, A.

1981-01-01

X-ray fluorescence has been applied to the determination of copper content of geological materials in the concentration range of 0.01 to % CuO. A molybdenum target tube Is used, samples being presented in finely-ground powder form. Various methods for the correction for background and Instrumental copper interferences have been considered. To correct for matrix effects different tube scattered primary radiations have been tested as references or internal standards. MoK(41 - (C) provides the most suitable results. The use of influence empirical coefficients for the effect of iron on copper and of mass absorption coefficients has also been considered. For samples with a high content of lead, several procedures to correct for I t s influence have been investigated. Comparison between data obtained by X-ray fluorescence and wet-chemical techniques indicated good agreement. (Author) 6 refs

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.

Hypoxia induces copper stable isotope fractionation in hepatocellular carcinoma, in a HIF-independent manner.

Science.gov (United States)

Bondanese, Victor P; Lamboux, Aline; Simon, Melanie; Lafont, Jérôme E; Albalat, Emmanuelle; Pichat, Sylvain; Vanacker, Jean-Marc; Telouk, Philippe; Balter, Vincent; Oger, Philippe; Albarède, Francis

2016-11-09

Hepatocellular carcinoma (HCC) is the most frequent type of primary liver cancer, with increasing incidence worldwide. The unrestrained proliferation of tumour cells leads to tumour hypoxia which in turn promotes cancer aggressiveness. While changes in the concentration of copper (Cu) have long been observed upon cancerization, we have recently reported that the isotopic composition of copper is also altered in several types of cancer. In particular, we showed that in hepatocellular carcinoma, tumour tissue contains heavier copper compared to the surrounding parenchyma. However, the reasons behind such isotopic signature remained elusive. Here we show that hypoxia causes heavy copper enrichment in several human cell lines. We also demonstrate that this effect of hypoxia is pH, HIF-1 and -2 independent. Our data identify a previously unrecognized cellular process associated with hypoxia, and suggests that in vivo tumour hypoxia determines copper isotope fractionation in HCC and other solid cancers.

Stress sources and manifestations in a nation-wide sample of pre-primary, primary and secondary educators in Greece

Directory of Open Access Journals (Sweden)

Nadia eKourmousi

2016-04-01

Full Text Available BackgroundTeachers experience high levels of stress as a result of their professional duties and research has shown a growing interest in this phenomenon during the recent years. Aim of this study was to explore the associations of stress sources and manifestations with individual and job-related characteristics in educators of all levels. MethodsIn a cross–sectional design, following an informative e-campaign on the study aims through the official and the main teachers’ portals in Greece, respondents completed online the Teachers Stress Inventory (TSI and the 14-item Perceived Stress Scale (PSS-14. 974 male and 2473 female pre-primary, primary and secondary educators with a mean age of 41.2 years responded. ResultsWomen and younger teachers reported significantly higher levels of stress, mainly due to lack of time and other work-related stressors, and also more emotional and gastronomic manifestations. Increased age and working experience were associated with lower levels of several stress sources. Teachers of administrative positions had increased time management stressors, but less professional distress, professional investment and discipline and motivation stressors. Additionally, working and residing far from family increased teachers’ stress levels associated to control, motivation and investment. Teachers of pre-primary education had reduced professional investment and motivation stress factors while vocational lyceum teachers of secondary education reported less work-related stressors and manifestations and more discipline and motivation related ones. Having students supported or in need of support from special educators and students with difficulties in speaking or comprehension was associated with most of the teachers' stress sources and manifestations (i.e. TSI subscales. Finally, colleagues’ and mainly supervisors' support seemed to provide a strong and consistent protection against both stress sources and manifestations

Synthesis of graphene by MEVVA source ion implantation

International Nuclear Information System (INIS)

Ying, J.J.; Xiao, X.H.; Dai, Z.G.; Wu, W.; Li, W.Q.; Mei, F.; Cai, G.X.; Ren, F.; Jiang, C.Z.

2013-01-01

Ion implantation provides a new synthesis route for graphene, and few-layered graphene synthesis by ion implantation has been reported. Here we show the synthesis of a single layer of high-quality graphene by Metal Vapor Vacuum Arc (MEVVA) source ion implantation. Polycrystalline nickel and copper thin films are implanted with MEVVA source carbon ions at 40 kV, followed by high-temperature thermal annealing and quenching. A Raman spectrum is applied to probe the quality and thickness of the prepared graphene. A single layer of high-quality graphene is grown on the nickel films, but not on the copper films. The growth mechanisms on the nickel and copper films are explained. MEVVA source ion implantation has been widely applied in industrial applications, demonstrating that this synthesis method can be generalized for industrial production

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.

Perceived Sources of Occupational Stress among Primary School Teachers in Delta State of Nigeria

Science.gov (United States)

Akpochafo, G. O.

2012-01-01

This study investigated the most prevalent sources of occupational stress and also the demographic variables of gender, age and length of service among primary school teachers in Delta State. Two research questions and three hypotheses guided the study. The study used a descriptive survey design. The population was the primary school teachers in…

Properties of thermal air plasma with admixing of copper and carbon

International Nuclear Information System (INIS)

Fesenko, S; Veklich, A; Boretskij, V; Cressault, Y; Gleizes, A; Teulet, Ph

2014-01-01

This paper deals with investigations of air plasma with admixing of copper and carbon. Model plasma source unit with real breaking arc was used for the simulation of real discharges, which can be occurred during sliding of Cu-C composite electrodes on copper wire at electromotive vehicles. The complex technique of plasma property studies is developed. From one hand, the radial profiles of temperature and electron density in plasma of electric arc discharge in air between Cu-C composite and copper electrodes in air flow were measured by optical spectroscopy techniques. From another hand, the radial profiles of electric conductivity of plasma mixture were calculated by solution of energy balance equation. It was assumed that the thermal conductivity of air plasma is not depending on copper or carbon vapor admixtures. The electron density is obtained from electric conductivity profiles by calculation in assumption of local thermodynamic equilibrium in plasma. Computed in such way radial profiles of electron density in plasma of electric arc discharge in air between copper electrodes were compared with experimentally measured profiles. It is concluded that developed techniques of plasma diagnostics can be reasonably used in investigations of thermal plasma with copper and carbon vapors

Pulp tissue from primary teeth: new source of stem cells

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Paloma Dias Telles

2011-06-01

Full Text Available SHED (stem cells from human exfoliated deciduous teeth represent a population of postnatal stem cells capable of extensive proliferation and multipotential differentiation. Primary teeth may be an ideal source of postnatal stem cells to regenerate tooth structures and bone, and possibly to treat neural tissue injury or degenerative diseases. SHED are highly proliferative cells derived from an accessible tissue source, and therefore hold potential for providing enough cells for clinical applications. In this review, we describe the current knowledge about dental pulp stem cells and discuss tissue engineering approaches that use SHED to replace irreversibly inflamed or necrotic pulps with a healthy and functionally competent tissue that is capable of forming new dentin.

Copper recovery from slag by indirect bio leaching

International Nuclear Information System (INIS)

Mazuelos, A.; Iglesias, N.; Romero, R.; Forcat, O.; Carranza, F.

2009-01-01

The main source of copper loss from a smelter is copper in discard slag. Slag can contain Cu in concentrations very much higher than those of many ores. Cu is present in slag entrained in very small drops of matte, white metal and blister copper occluded in fayalitic phase. In this work, the technical viability of the BRISA process, that is based on the indirect bio leaching, for this residue has been proved. A sample of slag, containing 2 % of copper, has been chemical, granulometric and metallographic characterized and it has been leached with ferric sulphate solutions in agitated reactors. The influence of several variables have been investigated. Once the best operating conditions had been selecting and an economic estimation had been done (with very really attractive results), the leaching stage has been designed for a plant of 30 tonnes per hour capacity. Cu extractions higher than 70% can be achieved with a residence time of only five hours. Despite of Cu(II) concentration in fed is as high as 30 g/l, bio oxidation stage can supply Fe(III) demanded by ferric leaching stage. (Author) 17 refs

Effects of roof and rainwater characteristics on copper concentrations in roof runoff.

Science.gov (United States)

Bielmyer, Gretchen K; Arnold, W Ray; Tomasso, Joseph R; Isely, Jeff J; Klaine, Stephen J

2012-05-01

Copper sheeting is a common roofing material used in many parts of the world. However, copper dissolved from roof sheeting represents a source of copper ions to watersheds. Researchers have studied and recently developed a simple and efficient model to predict copper runoff rates. Important input parameters include precipitation amount, rain pH, and roof angle. We hypothesized that the length of a roof also positively correlates with copper concentration (thus, runoff rates) on the basis that runoff concentrations should positively correlate with contact time between acidic rain and the copper sheet. In this study, a novel system was designed to test and model the effects of roof length (length of roof from crown to the drip edge) on runoff copper concentrations relative to rain pH and roof angle. The system consisted of a flat-bottom copper trough mounted on an apparatus that allowed run length and slope to be varied. Water of known chemistry was trickled down the trough at a constant rate and sampled at the bottom. Consistent with other studies, as pH of the synthetic rainwater decreased, runoff copper concentrations increased. At all pH values tested, these results indicated that run length was more important in explaining variability in copper concentrations than was the roof slope. The regression equation with log-transformed data (R(2) = 0.873) accounted for slightly more variability than the equation with untransformed data (R(2) = 0.834). In log-transformed data, roof angle was not significant in predicting copper concentrations.

Tissue distribution and excretion of copper-67 intraperitoneally administered to rats fed fructose or starch

International Nuclear Information System (INIS)

Holbrook, J.; Fields, M.; Smith, J.C. Jr.; Reiser, S.

1986-01-01

It has been suggested that impaired gut absorption of copper is the cause of the exacerbated copper deficiency signs in rats fed fructose when compared to rats fed starch. The present study was designed to examine how rats fed fructose or starch diets, either copper-deficient or supplemented, distributed and excreted 67 Cu when the isotope was administered i.p. Intraperitoneal administration was chosen in an effort to circumvent primary gut absorption as a factor in the metabolism of 67 Cu. After 7 wk of dietary treatment, rats received an i.p. injection of 67 Cu and were placed in metabolic cages for 4 d. Regardless of dietary carbohydrate, copper-deficient rats retained similar levels of radioactivity in various tissues and excreted similar amounts of 67 Cu in feces and urine. This similarity in copper metabolism in copper-deficient rats fed either fructose or starch when the gut was circumvented for isotope administration suggests that the gut could be responsible, at least in part, for the exacerbated signs associated with the copper deficiency in rats fed fructose. The possibility is discussed that alterations in metabolism may increase the requirement for copper when fructose is the main dietary carbohydrate

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

One hundred fold increase in current carrying capacity in a carbon nanotube-copper composite

Science.gov (United States)

Subramaniam, Chandramouli; Yamada, Takeo; Kobashi, Kazufumi; Sekiguchi, Atsuko; Futaba, Don N.; Yumura, Motoo; Hata, Kenji

2013-07-01

Increased portability, versatility and ubiquity of electronics devices are a result of their progressive miniaturization, requiring current flow through narrow channels. Present-day devices operate close to the maximum current-carrying-capacity (that is, ampacity) of conductors (such as copper and gold), leading to decreased lifetime and performance, creating demand for new conductors with higher ampacity. Ampacity represents the maximum current-carrying capacity of the object that depends both on the structure and material. Here we report a carbon nanotube-copper composite exhibiting similar conductivity (2.3-4.7 × 105Scm-1) as copper (5.8 × 105Scm-1), but with a 100-times higher ampacity (6 × 108Acm-2). Vacuum experiments demonstrate that carbon nanotubes suppress the primary failure pathways in copper as observed by the increased copper diffusion activation energy (~2.0eV) in carbon nanotube-copper composite, explaining its higher ampacity. This is the only material with both high conductivity and high ampacity, making it uniquely suited for applications in microscale electronics and inverters.

Tamil Chola Bronzes and Swamimalai Legacy: Metal Sources and Archaeotechnology

Science.gov (United States)

Srinivasan, Sharada

2016-08-01

This review explores the great copper alloy image casting traditions of southern India from archaeometallurgical and ethnometallurgical perspectives. The usefulness of lead isotope ratio and compositional analysis in the finger-printing and art historical study of more than 130 early historic, Pallava, Chola, later Chola, and Vijayanagara sculptures (fifth-eighteenth centuries) is highlighted, including Nataraja, Buddha, Parvati, and Rama images made of copper, leaded bronze, brass, and gilt copper. Image casting traditions at Swamimalai in Tamil Nadu are compared with artistic treatises and with the technical examination of medieval bronzes, throwing light on continuities and changes in foundry practices. Western Indian sources could be pinpointed for a couple of medieval images from lead isotope analysis. Slag and archaeometallurgical investigations suggest the exploitation of some copper and lead-silver sources in the Andhra and Karnataka regions in the early historic Satavahana period and point to probable copper sources for the medieval images in Karnataka, Tamil Nadu, and Andhra Pradesh. The general lower iron content in southern Indian bronzes perhaps renders the proximal copper-magnetite reserves of Seruvila in Sri Lanka as a less likely source. Given the lack of lead deposits in Sri Lanka, however, the match of the lead isotope signatures of a well-known Ceylonese Buddhist Tara in British Museum with a Buddha image from Nagapattinam in Tamil Nadu may underscore ties between the island nation and the southern Indian Tamil regions.

COPPER ACCUMULATION IN SOILS AND VEGETATION OF POLLUTED AREA COPŞA MICĂ

Directory of Open Access Journals (Sweden)

Nicoleta Vrînceanu

2010-01-01

Full Text Available The study carried out in order to estimate the distribution and accumulation of copper in soils and vegetation fromCopşa Mică area used a radial network centered in the source of pollution – S.C. SOMETRA S.A. Copşa Mică. Soil andplant samples taken from the radial nodes of the network were analyzed to determine the content of copper. Values ofcopper content in plant ranged between 4.2 mg/kg and 97 mg/kg. Based on these results has been obtained a regressionequation that estimates the copper content in plants as function of the total copper content in soil. The spontaneousvegetation developed in the investigated area includes plants belonging to the following species: Amaranthusretroflexus, Artemisia vulgaris, Asclepias syriaca, Calamagrostis epigeios, Calamagrostis pseudophragmites, Cynodondactylon, Daucus carota, Equisetum arvense, Phragmites australis, Picris hieracioides, Setaria glauca, Sinapisarvensis, Verbascum phlomoides and Xanthium strumarium. The copper pollution doesn’t represent a major problem inCopşa Mică area.

Solubility of Copper(II Sulfate and Dicopper Chloride Trihydroxide for Pigs

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C. S. Park

2016-11-01

Full Text Available This study was conducted to determine the solubility of copper (Cu in two sources of copper(II sulfate (CuSO4 including monohydrate and pentahydrate and three sources of dicopper chloride trihydroxide (dCCTH including α-form (dCCTH-α, β-form (dCCTH-β, and a mixture of α- and β-form (dCCTH-αβ at different pH and a 3-step in vitro digestion assay for pigs. In Exp. 1, Cu sources were incubated in water-based buffers at pH 2.0, 3.0, 4.8, and 6.8 for 4 h using a shaking incubator at 39°C. The CuSO4 sources were completely dissolved within 15 min except at pH 6.8. The solubility of Cu in dCCTH-α was greater (p<0.05 than dCCTH-β but was not different from dCCTH-αβ during 3-h incubation at pH 2.0 and during 2-h incubation at pH 3.0. At pH 4.8, there were no significant differences in solubility of Cu in dCCTH sources. Copper in dCCTH sources were non-soluble at pH 6.8. In Exp. 2, the solubility of Cu was determined during the 3-step in vitro digestion assay for pigs. All sources of Cu were completely dissolved in step 1 which simulated digestion in the stomach. In Exp. 3, the solubility of Cu in experimental diets including a control diet and diets containing 250 mg/kg of additional Cu from five Cu sources was determined during the in vitro digestion assay. The solubility of Cu in diets containing additional Cu sources were greater (p<0.05 than the control diet in step 1. In conclusion, the solubility of Cu was influenced by pH of digesta but was not different among sources based on the in vitro digestion assay.

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.

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

In vitro Solubility of Copper(II) Sulfate and Dicopper Chloride Trihydroxide for Pigs.

Science.gov (United States)

Park, C S; Kim, B G

2016-11-01

This study was conducted to determine the solubility of copper (Cu) in two sources of copper(II) sulfate (CuSO 4 ) including monohydrate and pentahydrate and three sources of dicopper chloride trihydroxide (dCCTH) including α-form (dCCTH-α), β-form (dCCTH-β), and a mixture of α- and β-form (dCCTH-αβ) at different pH and a 3-step in vitro digestion assay for pigs. In Exp. 1, Cu sources were incubated in water-based buffers at pH 2.0, 3.0, 4.8, and 6.8 for 4 h using a shaking incubator at 39°C. The CuSO 4 sources were completely dissolved within 15 min except at pH 6.8. The solubility of Cu in dCCTH-α was greater (pCopper in dCCTH sources were non-soluble at pH 6.8. In Exp. 2, the solubility of Cu was determined during the 3-step in vitro digestion assay for pigs. All sources of Cu were completely dissolved in step 1 which simulated digestion in the stomach. In Exp. 3, the solubility of Cu in experimental diets including a control diet and diets containing 250 mg/kg of additional Cu from five Cu sources was determined during the in vitro digestion assay. The solubility of Cu in diets containing additional Cu sources were greater (p<0.05) than the control diet in step 1. In conclusion, the solubility of Cu was influenced by pH of digesta but was not different among sources based on the in vitro digestion assay.

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.

The Baghdad that Was: Using Primary Sources to Teach World History

Science.gov (United States)

Schur, Joan Brodsky

2009-01-01

That primary source documents have the power to bring the past alive is no news to social studies teachers. What is new in the last 10 years is the number of digitized documents available online that teachers can download and use in their classrooms. Encouraging teachers to utilize this ever-increasing treasure trove of resources was the goal of…

Damage of copper by low energy xenon ions

International Nuclear Information System (INIS)

Babad-Zakhryapin, A.A.; Popenko, V.A.

1988-01-01

Changes in the copper crystal structure bombarded by xenon ions with 30-150 eV energy are studied. Foils of MOb copper mark, 10 mm in diameter and 100 μm thickness, are irradiated. The initial specimens are annealed in vacuum during 1 h at 900 K temperature. The specimens are bombarded by xenon ions in a water-cooled holder. A TE-O type accelerator serves as a xenon ion source. The ion energy varies within 30 to 150 eV range. The ion flux density is 8x10 16 ion/(cm 2 xs). It is shown that crystal structure variations at deep depths are observed not only at high (>1 keV), but at low ion energies down to several dozens of electronvolt as well. The crystal structure variation on copper irradiation by xenon ions with 30-150 eV energy is followed by formation of defects like dislocation loops, point defects in the irradiated target bulk

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.

Primary source of income is associated with differences in HIV risk behaviors in street-recruited samples

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Fernández-Esquer Maria E

2004-06-01

Full Text Available Abstract Background The relationship between primary source of income and HIV risk behaviors and the racial/ethnic differences in risk behavior profiles among disadvantaged populations have not been fully explored. This is unusual given that the phenomenon of higher risk in more disadvantaged populations is well-known but the mechanisms remain unclear. We examined the relationship between primary source of income and differences in HIV risk behaviors among four racial/ethnic groups in the southern United States. Methods Self-reported data on primary source of income and HIV risk behaviors were collected from 1494 African American, Hispanic, Asian, and White men and women in places of public congregation in Houston, Texas. Data were analyzed using calculation of percentages and by chi-square tests with Yates correction for discontinuity where appropriate. Results Data revealed that a higher proportion of whites were involved in sex for money exchanges compared to the other racial groups in this sample. The data suggest that similar street sampling approaches are likely to recruit different proportions of people by primary income source and by ethnicity. It may be that the study locations sampled are likely to preferentially attract those involved in illegal activities, specifically the white population involved in sex for drug or money exchanges. Research evidence has shown that people construct highly evolved sexual marketplaces that are localized and most unlikely to cross racial, ethnic, and socioeconomic or geographical boundaries. Thus, the areas that we sampled may have straddled a white sexual marketplace more than that of the other groups, leading to an over-representation of sex exchange in this group. Drug use was highest among those with illegal primary sources of income (sex exchange and drug dealing and theft, and they were also those most likely to have injected drugs rather than administered them by any other route (p Conclusions

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....

Cobalt—Styles of deposits and the search for primary deposits

Science.gov (United States)

Hitzman, Murray W.; Bookstrom, Arthur A.; Slack, John F.; Zientek, Michael L.

2017-11-30

Cobalt (Co) is a potentially critical mineral. The vast majority of cobalt is a byproduct of copper and (or) nickel production. Cobalt is increasingly used in magnets and rechargeable batteries. More than 50 percent of primary cobalt production is from the Central African Copperbelt. The Central African Copperbelt is the only sedimentary rock-hosted stratiform copper district that contains significant cobalt. Its presence may indicate significant mafic-ultramafic rocks in the local basement. The balance of primary cobalt production is from magmatic nickel-copper and nickel laterite deposits. Cobalt is present in several carbonate-hosted lead-zinc and copper districts. It is also variably present in Besshi-type volcanogenic massive sulfide and siliciclastic sedimentary rock-hosted deposits in back arc and rift environments associated with mafic-ultramafic rocks. Metasedimentary cobalt-copper-gold deposits (such as Blackbird, Idaho), iron oxide-copper-gold deposits, and the five-element vein deposits (such as Cobalt, Ontario) contain different amounts of cobalt. None of these deposit types show direct links to mafic-ultramafic rocks; the deposits may result from crustal-scale hydrothermal systems capable of leaching and transporting cobalt from great depths. Hydrothermal deposits associated with ultramafic rocks, typified by the Bou Azzer district of Morocco, represent another type of primary cobalt deposit.In the United States, exploration for cobalt deposits may focus on magmatic nickel-copper deposits in the Archean and Proterozoic rocks of the Midwest and the east coast (Pennsylvania) and younger mafic rocks in southeastern and southern Alaska; also, possibly basement rocks in southeastern Missouri. Other potential exploration targets include—The Belt-Purcell basin of British Columbia (Canada), Idaho, Montana, and Washington for different styles of sedimentary rock-hosted cobalt deposits;Besshi-type VMS deposits, such as the Greens Creek (Alaska) deposit and

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

International Nuclear Information System (INIS)

McCormick, Stephen F.

2016-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2016-03-25

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

Copper wire bonding

CERN Document Server

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

2014-01-01

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

Measurement and calculation of radiation sources in the primary cooling system of JOYO

International Nuclear Information System (INIS)

Suzuki, S.; Iizawa, K.; Ohtani, N.; Kobayashi, T.; Horie, J.; Handa, H.

1987-01-01

Production and transfer of radiation sources in the primary cooling system are important consideration in the LMFBR plant from the viewpoint of radiation protection and shielding design. These items were evaluated with calculations and/or measurements in the Japanese experimental fast reactor JOYO. In this study, calculations were made with the DOT3.5 0 two-dimensional discrete ordinate transport code to determine the neutron flux and production rate distributions of radiation sources in the reactor vessel. Using the DOT results, the behavior in primary coolant sodium of the CP (radioactive corrosion products) which were released from the reactor structural material was also calculationally analyzed with the PSYCHE code developed by PNC. These analytical results were compared with the measured results to get the verification of analysis methods and to estimate the accuracy of calculations

Lesions of Copper Toxicosis in Captive Marine Invertebrates With Comparisons to Normal Histology.

Science.gov (United States)

LaDouceur, E E B; Wynne, J; Garner, M M; Nyaoke, A; Keel, M K

2016-05-01

Despite increasing concern for coral reef ecosystem health within the last decade, there is scant literature concerning the histopathology of diseases affecting the major constituents of coral reef ecosystems, particularly marine invertebrates. This study describes histologic findings in 6 species of marine invertebrates (California sea hare [Aplysia californica], purple sea urchin [Strongylocentrotus purpuratus], sunburst anemone [Anthopleura sola], knobby star [Pisaster giganteus], bat star [Asterina miniata], and brittle star [Ophiopteris papillosa]) with spontaneous copper toxicosis, 4 purple sea urchins with experimentally induced copper toxicosis, and 1 unexposed control of each species listed. The primary lesions in the California sea hare with copper toxicosis were branchial and nephridial necrosis. Affected echinoderms shared several histologic lesions, including epidermal necrosis and ulceration and increased numbers of coelomocytes within the water-vascular system. The sunburst anemone with copper toxicosis had necrosis of both epidermis and gastrodermis, as well as expulsion of zooxanthellae from the gastrodermis. In addition to the lesions attributed to copper toxicosis, our results describe normal microscopic features of these animals that may be useful for histopathologic assessment of marine invertebrates. © The Author(s) 2015.

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

Extent of Head Teachers' Utilization of Innovative Sources of Funding Primary Schools in Enugu State of Nigeria

Science.gov (United States)

Amogechukwu, Eze Thecla; Unoma, Chidobi Roseline

2017-01-01

The purpose of this study was to examine the extent Head teachers utilize innovative sources of funding primary schools in Enugu State of Nigeria. Descriptive survey design was employed to examine the extent head teachers utilize innovative sources of funding primary schools in Enugu State. Data were collected through a 14-item questionnaire…

Hyperbranched Polyglycerol Derivatives as Prospective Copper Nanotransporter Candidates

Directory of Open Access Journals (Sweden)

Mohiuddin Quadir

2018-05-01

Full Text Available Hyperbranched polyglycerol (hPG has been used as a multivalent scaffold to develop a series of nanocarriers capable of high-affinity encapsulation of copper (Cu. A rationally selected set of Cu-complexing motifs has been conjugated to hPG hydroxyl groups to render the constructs potentially usable as exogenous sources of Cu for addressing different pathological conditions associated with Cu-deficiency. We have utilized a newly discovered route to attach Cu-binding domains exclusively within a hPG core by selective differentiation between the primary and secondary hydroxyl groups of the polyol. These hPG-derivatives were found to form a stable complex with Cu ions depending on the type of immobilized ligands and corresponding degree of functionalization. In addition, these Cu-bearing nano-complexes demonstrated moderately cationic surface charge resulting in adjustable protein-binding characteristics and low cellular toxicity profile. We envision that these Cu-loaded hPG nanocarriers can be used as a stable platform to transport the metal ion across the systemic circulation to supply bioavailable quantity of Cu in disease-afflicted tissues.

Cell Wall Composition of Neurospora crassa Under Conditions of Copper Toxicity

OpenAIRE

Subramanyam, C.; Venkateswerlu, G.; Rao, S. L. N.

1983-01-01

The mycelia of Neurospora crassa grown in the presence of high concentrations of copper were blue in color, but only on a medium containing inorganic nitrate and phosphate as the nitrogen and phosphate sources, respectively. The cell wall isolate of the blue mycelia contained large amounts (12%) of copper and higher amounts of chitosan, phosphate, and amino groups, with a 42% decrease in the chitin content. Although all the glucosamine of the cell wall of control cultures could be released wi...

New configuration for efficient and durable copper coating on the outer surface of a tube

Directory of Open Access Journals (Sweden)

Irfan Ahmad

2017-03-01

Full Text Available A well-adhered copper coating on stainless steel power coupler parts is required in superconducting radio frequency (SRF accelerators. Radio frequency power coupler parts are complex, tubelike stainless steel structures, which require copper coating on their outer and inner surfaces. Conventional copper electroplating sometimes produces films with inadequate adhesion strength for SRF applications. Electroplating also requires a thin nickel strike layer under the copper coating, whose magnetic properties can be detrimental to SRF applications. Coaxial energetic deposition (CED and sputtering methods have demonstrated efficient conformal coating on the inner surfaces of tubes but coating the outer surface of a tube is challenging because these coating methods are line of sight. When the substrate is off axis and the plasma source is on axis, only a small section of the substrate’s outer surface is exposed to the source cathode. The conventional approach is to rotate the tube to achieve uniformity across the outer surface. This method results in poor film thickness uniformity and wastes most of the source plasma. Alameda Applied Sciences Corporation (AASC has developed a novel configuration called hollow external cathode CED (HEC-CED to overcome these issues. HEC-CED produces a film with uniform thickness and efficiently uses all eroded source material. The Cu film deposited on the outside of a stainless steel tube using the new HEC-CED configuration survived a high pressure water rinse adhesion test. HEC-CED can be used to coat the outside of any cylindrical structure.

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

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.

An RF ion source based primary ion gun for secondary ion mass spectroscopy

International Nuclear Information System (INIS)

Menon, Ranjini; Nabhiraj, P.Y.; Bhandari, R.K.

2011-01-01

In this article we present the design, development and characterization of an RF plasma based ion gun as a primary ion gun for SIMS application. RF ion sources, in particular Inductively Coupled Plasma (ICP) ion sources are superior compared to LMIS and duoplasmtron ion sources since they are filamentless, can produce ions of gaseous elements. At the same time, ICP ion sources offer high angular current density which is an important factor in producing high current in small spot size on the target. These high current microprobes improve the signal to noise ratio by three orders as compared to low current ion sources such as LMIS. In addition, the high current microprobes have higher surface and depth profiling speeds. In this article we describe a simple ion source in its very basic form, two lens optical column and characteristics of microprobe

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.

Os isotopes and cooper sources for stratiform (mantos) cooper deposits of Chile

International Nuclear Information System (INIS)

Munizaga, Francisco; Ruiz, Joaquin; Freydier, Claire

1998-01-01

The sources of copper have been determined by studying trace elements osmium and rhenium as well as osmium isotope ratio in copper-bearing porphyry of Chuquicamata, el Teniente and Andacollo and in the stratiform copper deposits of Mantos Blancos, El Soldado, Cerro Negro and Talcuna

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

Science.gov (United States)

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

2014-01-01

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

Copper hypersensitivity

DEFF Research Database (Denmark)

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

2014-01-01

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

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.

Speciation and fate of copper in sewage treatment works with and without tertiary treatment: the effect of return flows.

Science.gov (United States)

Innaa, D; Lester, J N; Scrimshawb, M D; Cartmell, E

2014-01-01

The removal of metals from wastewaters is becoming an important issue, with new environmental quality standards putting increased regulatory pressure on operators of sewage treatment works. The use of additional processes (tertiary treatment) following two-stage biological treatment is frequently seen as a way of improving effluent quality for nutrients and suspended solids, and this study investigates the impact of how back washes from these tertiary processes may impact the removal of copper during primary sedimentation. Seven sites were studied, three conventional two-stage biological treatment, and four with tertiary processes. It was apparent that fluxes of copper in traditional return flows made a significant contribution to the load to the primary treatment tanks, and that tanks. These return flows had an impact on copper removal in the primary tanks, probably due to their aerobic nature. Returning such aerobic back wash flows to the main process stream after primary treatment may therefore be worth consideration. The opportunity to treat consolidated liquor and sludge.flows in side-stream processes to remove toxic elements, as they are relatively concentrated, low volume flow streams, should also be evaluated.

Copper nanoparticles synthesis by gamma irradiation in chitosan aqueous system

International Nuclear Information System (INIS)

Shahrul Izwan Ahmad; Md Soot Ahmad; Shahidan Radiman

2009-01-01

A study on effect of chitosan concentration on the copper nanoparticles synthesis using gamma irradiation as source of reducing agent has been done at total absorbed dose of 50 kGy. The addition of ethanol is vital as scavenger of oxidation radical that eliminate the function of reducing agent produced by radiolysis process of gamma ray in water system. Transmission electron microscopy observations show the formation of copper nanoparticles embedded in chitosan matrix. As the concentration of chitosan increase the solution become darker and nanoparticles produced are densely, in order form with polydisperse size. While at the low concentration of chitosan, the color of solution become more reddish and the particles produced are monodisperse in size with regular shape and more orderly. The phase of pure copper nanoparticles embedded in the chitosan matrix was confirmed by X-ray diffraction. (Author)

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 and Lead levels in two popular leafy vegetables grown ...

African Journals Online (AJOL)

forming an important source of vitamins and minerals ... and the interaction with other metals (Zurera et al., ... is an essential trace element in the functions of the ... The levels of Lead and Copper varied between the vegetable varieties and from ...

Graphite fiber/copper matrix composites for space power heat pipe fin applications

International Nuclear Information System (INIS)

Mcdanels, D.L.; Baker, K.W.; Ellis, D.L.

1991-01-01

High specific thermal conductivity (thermal conductivity divided by density) is a major design criterion for minimizing system mass for space power systems. For nuclear source power systems, graphite fiber reinforced copper matrix (Gr/Cu) composites offer good potential as a radiator fin material operating at service temperatures above 500 K. Specific thermal conductivity in the longitudinal direction is better than beryllium and almost twice that of copper. The high specific thermal conductivity of Gr/Cu offers the potential of reducing radiator mass by as much as 30 percent. Gr/Cu composites also offer the designer a range of available properties for various missions and applications. The properties of Gr/Cu are highly anisotropic. Longitudinal elastic modulus is comparable to beryllium and about three times that of copper. Thermal expansion in the longitudinal direction is near zero, while it exceeds that of copper in the transverse direction. 5 refs

Effects of phosphourus addition on the physical properties and surface condition of tungsten-copper composites

International Nuclear Information System (INIS)

Akiyoshi, N.; Nakada, K.; Nakayama, M.; Kohda, K.

2001-01-01

Tungsten-copper composites containing a small amount of phosphorus prepared using conventional P/M method. Cu 3 P powder was used as phosphorous source. The effects of phosphorus addition on the physical properties and the surface condition were investigated and the existing form of phosphorus was specified on the tungsten-copper composites The results are summarized as follows. The tungsten-copper composite containing 10 % copper, for example, demonstrated optimum thermal conductivity at the phosphorus addition of 0.02 %. The density of the composites was almost 100 % and the surface of the sintered body was flat and smooth after sintering at a temperature between 1100 and 1150 o C. It was shown that phosphorus exists as Co 2 P. (author)

Copper in the sediment and sea surface microlayer near a fallowed, open-net fish farm.

Science.gov (United States)

Loucks, Ronald H; Smith, Ruth E; Fisher, Clyde V; Fisher, E Brian

2012-09-01

Sediment and sea surface microlayer samples near an open-net salmon farm in Nova Scotia, were analysed for copper. Copper is a constituent of the feed and is an active ingredient of anti-foulants. The salmon farm was placed in fallow after 15 years of production. Sampling was pursued over 27 months. Elevated copper concentrations in the sediments indicated the farm site as a source. Bubble flotation due to gas-emitting sediments from eutrophication is a likely process for accumulating copper in the sea surface microlayer at enriched concentrations. Elevated and enriched concentrations in the sea surface microlayer over distance from the farm site led, as a result of wind-drift, to an enlarged farm footprint. The levels of copper in both sediments and sea surface microlayer exceeded guidelines for protection of marine life. Over the 27 months period, copper levels persisted in the sediments and decreased gradually in the sea surface microlayer. Copyright © 2012 Elsevier Ltd. All rights reserved.

Emissions of naturally occurring radioactivity from aluminum and copper facilities. Report No. 6 (final)

International Nuclear Information System (INIS)

Andrews, V.E.

1982-11-01

This report summarizes five surveys which were conducted at a Bauxite mining operation, an alumina reduction plant, an aluminum reduction plant, an underground copper mine and mill, and an open pit copper mine and concentrator. Process components and controlled source releases were sampled for naturally occurring radioactivity. Particular emphasis was given to radon-222, lead-210, and polonium-210 emissions from crushing and drying processes

Linking source region and ocean wave parameters with the observed primary microseismic noise

Science.gov (United States)

Juretzek, C.; Hadziioannou, C.

2017-12-01

In previous studies, the contribution of Love waves to the primary microseismic noise field was found to be comparable to those of Rayleigh waves. However, so far only few studies analysed both wave types present in this microseismic noise band, which is known to be generated in shallow water and the theoretical understanding has mainly evolved for Rayleigh waves only. Here, we study the relevance of different source region parameters on the observed primary microseismic noise levels of Love and Rayleigh waves simultaneously. By means of beamforming and correlation of seismic noise amplitudes with ocean wave heights in the period band between 12 and 15 s, we analysed how source areas of both wave types compare with each other around Europe. The generation effectivity in different source regions was compared to ocean wave heights, peak ocean gravity wave propagation direction and bathymetry. Observed Love wave noise amplitudes correlate comparably well with near coastal ocean wave parameters as Rayleigh waves. Some coastal regions serve as especially effective sources for one or the other wave type. These coincide not only with locations of high wave heights but also with complex bathymetry. Further, Rayleigh and Love wave noise amplitudes seem to depend equally on the local ocean wave heights, which is an indication for a coupled variation with swell height during the generation of both wave types. However, the wave-type ratio varies directionally. This observation likely hints towards a spatially varying importance of different source mechanisms or structural influences. Further, the wave-type ratio is modulated depending on peak ocean wave propagation directions which could indicate a variation of different source mechanism strengths but also hints towards an imprint of an effective source radiation pattern. This emphasizes that the inclusion of both wave types may provide more constraints for the understanding of acting generation mechanisms.

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...

Quantitative evaluation of emission controls on primary and secondary organic aerosol sources during Beijing 2008 Olympics

Directory of Open Access Journals (Sweden)

S. Guo

2013-08-01

Full Text Available To assess the primary and secondary sources of fine organic aerosols after the aggressive implementation of air pollution controls during the 2008 Beijing Olympic Games, 12 h PM2.5 values were measured at an urban site at Peking University (PKU and an upwind rural site at Yufa during the CAREBEIJING-2008 (Campaigns of Air quality REsearch in BEIJING and surrounding region summer field campaign. The average PM2.5 concentrations were 72.5 ± 43.6 μg m−3 and 64.3 ± 36.2 μg m−3 (average ± standard deviation, below as the same at PKU and Yufa, respectively, showing the lowest concentrations in recent years. Combining the results from a CMB (chemical mass balance model and secondary organic aerosol (SOA tracer-yield model, five primary and four secondary fine organic aerosol sources were compared with the results from previous studies in Beijing. The relative contribution of mobile sources to PM2.5 concentrations was increased in 2008, with diesel engines contributing 16.2 ± 5.9% and 14.5 ± 4.1% and gasoline vehicles contributing 10.3 ± 8.7% and 7.9 ± 6.2% to organic carbon (OC at PKU and Yufa, respectively. Due to the implementation of emission controls, the absolute OC concentrations from primary sources were reduced during the Olympics, and the contributions from secondary formation of OC represented a larger relative source of fine organic aerosols. Compared with the non-controlled period prior to the Olympics, primary vehicle contributions were reduced by 30% at the urban site and 24% at the rural site. The reductions in coal combustion contributions were 57% at PKU and 7% at Yufa. Our results demonstrate that the emission control measures implemented in 2008 significantly alleviated the primary organic particle pollution in and around Beijing. However, additional studies are needed to provide a more comprehensive assessment of the emission control effectiveness on SOA formation.

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

Development of a certified reference material for composition of high-purity copper as a transfer standard within GET 176-2013

Directory of Open Access Journals (Sweden)

Veniamin M. Zyskin

2017-01-01

Full Text Available Introduction. The paper gives information on the development of a certified reference material (CRM for composition of high-purity copper (Cu CRM UNIIM. The CRM is included as the transfer standard into the State primary standard of the mass (molar fraction and mass (molar concentration of the component in liquid and solid substances and materials based on coulometry GET 176-2013.Materials and methods. The CRM represents pieces of oxygen-free copper wire rod, brand KMB, produced according to GOST R 53803-2010, weighing from 0.5 to 1g. The CRM is packed in plastic vials with the capacity of 30 or 50 cm3. The certified characteristic of the CRM is copper mass fraction in copper wire rod, expressed in percentages. The certified value for copper mass fraction was established by the primary method of controlled-potential coulometry using the State primary standard GET 176-2013.Results. The permitted interval of the certified value for copper mass fraction in the CRM is from 99,950 % to 100,000 %. The relative expanded uncertainty (k=2 of the certified value for copper mass fraction does not exceed 0,030 %; the relative standard uncertainty due to inhomogeneity does not exceed 0.010 %; the relative standard uncertainty due to instability does not exceed 0.010 %. The shelf life of the developed CRM is 10 years provided that standard storage conditions are ensured.Discussion and conclusions. The developed CRM is included into the State register of type approved RMs under the number GSO 10800-2016. The CRM of high-purity copper (Cu CRM UNIIM as a transfer standard is intended for reproduction, storage and transfer of the copper mass fraction unit to other reference materials and chemical reagents by the method of comparison using a comparator and by conducting direct measurements. This CRM may also be used:– for verification of measuring instruments (MIs according to the state verification schedule described in GOST R 8.735.0-2014,– for calibration

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.

Investigation of the possibility of copper recovery from the flotation tailings by acid leaching.

Science.gov (United States)

Antonijević, M M; Dimitrijević, M D; Stevanović, Z O; Serbula, S M; Bogdanovic, G D

2008-10-01

The flotation tailings pond of the Bor Copper Mine poses a great ecological problem not only for the town of Bor but also for the surrounding soils and watercourses. Since the old flotation tailings contain about 0.2% of copper on the average, we investigated their leaching with sulphuric acid in the absence and presence of an oxidant. The aim was to determine the leaching kinetics of copper and iron as affected by various factors such as: the pH value of the leach solution, stirring speed, pulp density, particle size, concentration of ferric ions, temperature and time for leaching. The average copper and iron recovery obtained was from 60% to 70% and from 2% to 3%, respectively. These results indicate that the old flotation tailings pond represents an important source of secondary raw material for the extraction of copper and that it should be valorized rather than land reclamation. At the end of the paper, a mechanism of dissolution of copper and iron minerals from the tailings was described.

Radiation effects limits on copper in superconducting magnets

International Nuclear Information System (INIS)

Guinan, M.W.

1984-01-01

The determination of the response of copper stabilizers to neutron irradiation in fusion reactor superconducting magnets requires information in four areas. (1) Neutron flux and spectrum determination are a major factor in the accuracy with which stabilizer response can be predicted. Since magnet stability depends on the weakest link, calculations must be made in sufficient detail to fully account for steep flux gradients and local pertubations from penetrations. (2) Resistivity changes at zero field in magnet spectra are generally calculated from the damage energy cross-section or the equivalent displacement (dpa) rate. (3) Resistivity changes at field for conceptual designs are generally determined from the changes predicted at zero field by the use of a Kohler plot. The cyclic irradiation and annealing, expected to be characteristic of fusion reactor magnet operation, is presently the largest source of uncertainty in determining the limits of neutron exposure for copper stabilizers. Applications of our current understanding of the limits of copper stabilizers in fusion reactor designs are explored in two examples. Recommendations for future additions to the data base are discussed

76 FR 38024 - Standards of Performance for New Stationary Sources

Science.gov (United States)

2011-06-29

... January 20, 1983. O Sewage Treatment Plants X X P Primary Copper Smelters X X Q Primary Zinc Smelters X X R Primary Lead Smelters X X S Primary Aluminum Reduction Plants X X T Phosphate Fertilizer Industry: X X Wet Process Phosphoric Acid Plants. U Phosphate Fertilizer Industry: X X Superphosphoric Acid...

The derivation of water quality criteria of copper in Biliu River

Science.gov (United States)

Zheng, Hongbo; Jia, Xinru

2018-03-01

Excessive copper in water can be detrimental to the health of human and aquatic life. China has promulgated Environmental Quality Standards for Surface Water to control water pollution, but uniform standard values may cause under-protection or over-protection. Therefore, the basic research work on water quality criteria of water source or reservoir is urgently needed. This study deduces the acute and chronic Water Quality Criteria (WQC) of copper in Biliu River by Species Sensitivity Distribution method (SSD). The result shows that BiDoseResp is the most suitable model and the acute and chronic water quality benchmark of copper are 10.72 µg•L-1 and 5.86 µg•L-1. This study provides basis for the construction of water quality standard of Liaoning and the environmental management of Biliu River.

Synthesis of Copper-Chelates Derived from Amino Acids and Evaluation of Their Efficacy as Copper Source and Growth Stimulator for Lactuca sativa in Nutrient Solution Culture.

Science.gov (United States)

Kaewchangwat, Narongpol; Dueansawang, Sattawat; Tumcharern, Gamolwan; Suttisintong, Khomson

2017-11-15

Five tetradentate ligands were synthesized from l-amino acids and utilized for the synthesis of Cu(II)-chelates 1-5. The efficacy of Cu(II)-chelates as copper (Cu) source and growth stimulator in hydroponic cultivation was evaluated with Lactuca sativa. Their stability test was performed at pH 4-10. The results suggested that Cu(II)-chelate 3 is the most pH tolerant complex. Levels of Cu, Zn, and Fe accumulated in plants supplied with Cu(II)-chelates were compared with those supplied with CuSO 4 at the same Cu concentration of 8.0 μM. The results showed that Cu(II)-chelate 3 significantly enhanced Cu, Zn, and Fe content in shoot by 35, 15, and 48%, respectively. Application of Cu(II)-chelate 3 also improved plant dry matter yield by 54%. According to the results, Cu(II)-chelate 3 demonstrated the highest stimulating effect on plant growth and plant mineral accumulation so that it can be used as an alternative to CuSO 4 for supplying Cu in nutrient solutions and enhancing the plant growth.

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.

Long term energy-related environmental issues of copper production

International Nuclear Information System (INIS)

Alvarado, S.; Maldonado, P.; Barrios, A.; Jaques, I.

2002-01-01

Primary copper production is a major activity in the mining sector of several countries. However, it is highly energy-intensive and poses important environmental hazards. In the case of Chile, the world's largest copper producer (40% of world total), we examine its energy consumption and energy-related environmental implications over a time horizon of 25 years. Concerning the latter, we focus on greenhouse-gas (GHG) emissions, one of the most debated environmental issues. This paper follows up our previous report in which the current situation was analyzed and a particular technical option for improving the energy efficiency and concurrently reducing GHG emissions was discussed. Estimated reference or base (BS) and mitigation (MS) scenarios are developed for the period ending in 2020. The former assesses the energy demand projected in accordance with production forecasts and specific energy consumption patterns (assuming that energy efficiency measures are adopted 'spontaneously') with their resultant GHG emissions, while the latter assumes induced actions intended to reduce emissions by adopting an aggressive policy of efficient energy use. For the year 2020, the main results are: (i) BS, 1214 t of CO 2 /ton of refined copper content (49% lower than in 1994); (ii) MS, 1037 t of CO 2 /t of refined copper content (56% lower than in 1994). CO 2 emissions have been estimated considering both fuel and electricity process requirements. (author)

Magnesium-aerial primary current source

Directory of Open Access Journals (Sweden)

Barba I. N.

2007-12-01

Full Text Available Novel metal-air chemical power sources (CPS 3,0-ВМБ-7,5 have been developed. They have an unlimited shelf life and, even after decades of storage, give almost 100% of the designed capacity. These sources are water-activated. An aqueous salt solution is used as an electrolyte. Such sources are designed for single continuous or discontinuous discharge. The paper presents electrochemical reactions at the electrodes during CPS discharge. Comparison of electrical characteristics of the developed power source and various types of "dry cells" has shown that the developed sources have higher energy characteristics.

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.

Efficient removal of copper from wastewater by using mechanically activated calcium carbonate.

Science.gov (United States)

Hu, Huimin; Li, Xuewei; Huang, Pengwu; Zhang, Qiwu; Yuan, Wenyi

2017-12-01

Copper removal from aqueous solution is necessary from the stances of both environmental protection and copper resource recycling. It is important to develop a new chemical precipitation method suitable for removing copper particularly at low concentration as the case of waste mine water, with regards to the various problems related to the current precipitation methods by using strong alkalis or soluble sulfides. In this research, we studied a possible chemical precipitation of copper ions at concentration around 60 mg/L or lower by cogrinding copper sulfate in water with calcium carbonate (CaCO 3 ) using wet stirred ball milling. With the aid of ball milling, copper precipitation as a basic sulfate (posnjakite: Cu 4 (SO 4 ) (OH) 6 ·H 2 O) occurred at a very high copper removal rate of 99.76%, to reduce the residual copper concentration in the solution less than 0.5 mg/L, reaching the discharge limit, even with the addition amount of CaCO 3 as a stoichiometric ratio of CaCO 3 /Cu 2+ at 1:1. It is more interesting to notice that, at the same conditions, other heavy metals such as Ni, Mn, Zn and Cd do not precipitate obviously just with CaCO 3 addition at CaCO 3 /M 2+ at 1:1 so that the precipitate without the impurities can be processed as good source to recover copper. This newly proposed concept can be further developed to treat wastewaters with other metals to serve both purposes of environmental purification and resource recovery in a similar way. Copyright © 2017 Elsevier Ltd. All rights reserved.

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.

Chemicals in effluent waters from nuclear power stations: the distribution, fate, and effects of copper

International Nuclear Information System (INIS)

Harrison, F.L.

1984-04-01

This report provides a summary of research performed to determine the physicochemical forms and fate of copper in effluents from power stations adjacent to aquatic ecosystems with water that differs in salinity, pH, and concentrations of organic and inorganic constituents. In addition, research performed to evaluate responses of selected ecologically and economically important marine and freshwater organisms to increased concentrations of soluble copper is reviewed. The same parameters were measured and the same analytical techniques were used throughout the study. Copper concentration and speciation, in influent and effluent waters collected from eight power stations using copper alloys in their cooling systems, showed that the quantities of copper associated with particles, colloids, and organic and inorganic ligands differed with the site, season, and mode of operation of the station. Under normal operating conditions, the differences between influent and effluent waters were generally small, and most of the copper was in bound (complexed) species except when low pH water was circulated. However, copper was high in concentration and present in labile species during start-up of water circulation through some cooling systems and during changeover from open-cycle to closed-cycle operation. The toxic response to copper differed with the species and life stage of the organism and with the chemical form of copper in the water. Our primary emphasis was on acute effects and most of the testing was performed under controlled laboratory conditions. However, sublethal effects of copper on a population of bluegills living in a power station cooling lake containing water of low pH and on a population exposed to increased soluble copper in the laboratory were also assessed. 105 references, 15 figures, 11 tables

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.

Towards a thermally regenerative all-copper redox flow battery

OpenAIRE

Peljo, Pekka; Lloyd, David; Nguyet, Doan; Majaneva, Marko; Kontturi, Kyosti

2014-01-01

An all-copper redox flow battery based on strong complexation of Cu+ with acetonitrile is demonstrated, exhibiting reasonable battery performance. More interestingly, the battery can be charged by heat sources of 100 degrees C, by distilling off the acetonitrile. This destabilizes the Cu+ complex, leading to recovery of the starting materials.

Towards a thermally regenerative all-copper redox flow battery.

Science.gov (United States)

Peljo, Pekka; Lloyd, David; Doan, Nguyet; Majaneva, Marko; Kontturi, Kyösti

2014-02-21

An all-copper redox flow battery based on strong complexation of Cu(+) with acetonitrile is demonstrated, exhibiting reasonable battery performance. More interestingly, the battery can be charged by heat sources of 100 °C, by distilling off the acetonitrile. This destabilizes the Cu(+) complex, leading to recovery of the starting materials.

Metavanadate causes cellular accumulation of copper and decreased lysyl oxidase activity

International Nuclear Information System (INIS)

Cui, Changtai T.; Uriu-Adams, Janet Y.; Tchaparian, Eskouhie H.; Keen, Carl L.; Rucker, Robert B.

2004-01-01

Selected indices of copper metabolism in weanling rats and fibroblast cultures were progressively altered in response to increased levels of sodium metavanadate. In diets, vanadium was added in amounts ranging from 0 to 80 μg V/g of diet, that is, 0-1.6 μmol V/g of diet. In fibroblast cultures, vanadium ranged from 0 to 400 nmol V/ml. The inhibition of P-ATPase-7A activity by metavanadate, important to copper egress from cells, was a primary focus. In skin, and tendon, the copper concentration was increased in response to increased dietary levels of metavanadate, whereas lysyl oxidase activity, a secreted cuproprotein, was reduced. The reduction in lysyl oxidase activity was also accompanied by reduced redox cycling potential of isolated fractions of lysyl oxidase, presumably due to reduced lysyltyrosyl quinone (LTQ) formation at the active site of lysyl oxidase. In contrast, liver copper concentrations and plasma ceruloplasmin activity were not affected by metavanadate exposure. However, semicarbazide-sensitive benzylamine oxidase (SCBO) activity, which was taken as an indirect measure of vascular adhesive protein-1 (VAP-1), was increased. In cultured fibroblasts, cellular copper was also increased and lysyl oxidase decreased in response to metavanadate. Moreover, the steady-state levels of atp7a and lysyl oxidase mRNAs were not affected by addition of metavanadate to culture medium up to 200 nmol/ml. Taken together, these data suggest that pathways involving copper egress and lysyl oxidase activation are particularly sensitive to metavanadate exposure through processes that are predominately posttranslational

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...

Copper corrosion and its relationship to solar collectors:a compendium.

Energy Technology Data Exchange (ETDEWEB)

Menicucci, David F.; Mahoney, Alan Roderick

2007-07-01

Copper has many fine qualities that make it a useful material. It is highly conductive of both heat and electricity, is ductile and workable, and reasonably resistant to corrosion. Because of these advantages, the solar water heating industry has been using it since the mid-1970s as the material of choice for collectors, the fundamental component of a solar water heating system. In most cases copper has performed flawlessly, but in some situations it has been known to fail. Pitting corrosion is the usual failure mode, but erosion can also occur. In 2000 Sandia National Laboratories and the Copper Development Association were asked to analyze the appearance of pin-hole leaks in solar collector units installed in a housing development in Arizona, and in 2002 Sandia analyzed a pitting corrosion event that destroyed a collector system at Camp Pendleton. This report includes copies of the reports and accounts of these corrosion failures, and provides a bibliography with references to many papers and articles that might be of benefit to the solar community. It consolidates in a single source information that has been accumulated at Sandia relative to copper corrosion, especially as it relates to solar water heaters.

Tempo of magma degassing and the genesis of porphyry copper deposits.

Science.gov (United States)

Chelle-Michou, Cyril; Rottier, Bertrand; Caricchi, Luca; Simpson, Guy

2017-01-12

Porphyry deposits are copper-rich orebodies formed by precipitation of metal sulphides from hydrothermal fluids released from magmatic intrusions that cooled at depth within the Earth's crust. Finding new porphyry deposits is essential because they are our largest source of copper and they also contain other strategic metals including gold and molybdenum. However, the discovery of giant porphyry deposits is hindered by a lack of understanding of the factors governing their size. Here, we use thermal modelling and statistical simulations to quantify the tempo and the chemistry of fluids released from cooling magmatic systems. We confirm that typical arc magmas produce fluids similar in composition to those that form porphyry deposits and conclude that the volume and duration of magmatic activity exert a first order control on the endowment (total mass of deposited copper) of economic porphyry copper deposits. Therefore, initial magma enrichment in copper and sulphur, although adding to the metallogenic potential, is not necessary to form a giant deposit. Our results link the respective durations of magmatic and hydrothermal activity from well-known large to supergiant deposits to their metal endowment. This novel approach can readily be implemented as an additional exploration tool that can help assess the economic potential of magmatic-hydrothermal systems.

Use of copper radioisotopes in investigating disorders of copper metabolism

International Nuclear Information System (INIS)

Camakaris, J.; Voskoboinik, I.; Brooks, H.; Greenough, M.; Smith, S.; Mercer, J.

1998-01-01

Full text: Copper is an essential trace element for life as a number of vital enzymes require it. Copper deficiency can lead to neurological disorders, osteoporosis and weakening of arteries. However Cu is also highly toxic and homeostatic mechanisms have evolved to maintain Cu at levels which satisfy requirements but do not cause toxicity. Toxicity is mediated by the oxidative capacity of Cu and its ability to generate toxic free radicals. There are several acquired and inherited diseases due to either Cu toxicity or Cu deficiency. The study of these diseases facilitates identification of genes and proteins involved in copper homeostasis, and this in turn will provide rational therapeutic approaches. Our studies have focused on Menkes disease in humans which is an inherited and usually lethal copper deficiency. Using copper radioisotopes 64 Cu (t 1/2 = 12.8 hr) and 67 Cu (t 1/2 = 61 hr) we have studied the protein which is mutated in Menkes disease. This is a transmembrane copper pump which is responsible for absorption of copper into the body and also functions to pump out excess Cu from cells when Cu is elevated. It is therefore a vital component of normal Cu homeostasis. We have provided the first biochemical evidence that the Menkes protein functions as a P-type ATPase Cu pump (Voskoboinik et al., FEBS Letters, in press) and these data will be discussed. The assay involved pumping of radiocopper into purified membrane vesicles. Furthermore we have transfected normal and mutant Menkes genes into cells and are carrying out structure-function studies. We are also studying the role of amyloid precursor protein (APP) as a Cu transport protein in order to determine how Cu regulates this protein and its cleavage products. These studies will provide vital information on the relationship between Cu and APP and processes which lead to Alzheimers disease

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

Directory of Open Access Journals (Sweden)

Bahaa Sami Mahdi

2018-05-01

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

Giving Women the Vote: Using Primary Source Documents to Teach about the Fight for Women's Suffrage.

Science.gov (United States)

Jacobsen, Margaret

1988-01-01

Presents a lesson in which students use primary sources to learn about the organizing strategies used in the fight for women's suffrage. These sources will provide insights into the past and help students develop appreciation for the hardships suffragists endured. Includes objectives, procedures, and suggestions for activities. (LS)

Behavior of Copper Oxide Nanoparticles in Soil Pore Waters as Influenced by Soil Characteristics, Bacteria, and Wheat Roots

OpenAIRE

Hortin, Joshua

2017-01-01

The goal of this project was to study the behavior of copper oxide nanoparticles in soil environments. Copper oxide nanoparticles have antimicrobial properties and may also be used in agricultural settings to provide a source of copper for plant health, but accidental or misapplication of these nanoparticles to soil may be damaging to the plant and its associated bacteria. Dissolved soil organic matter that is present in soil pore waters dissolved nanoparticles, but did not dissolve the ex...

Bacterial Killing by Dry Metallic Copper Surfaces▿

OpenAIRE

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

2010-01-01

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

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

Science.gov (United States)

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

2012-04-01

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

40 CFR 440.104 - New source performance standards (NSPS).

Science.gov (United States)

2010-07-01

... GUIDELINES AND STANDARDS ORE MINING AND DRESSING POINT SOURCE CATEGORY Copper, Lead, Zinc, Gold, Silver, and... copper, lead, zinc, gold, silver, or molybdenum bearing ores or any combination of these ores from open... discharge of process wastewater to navigable waters from mills that use the froth-flotation process alone...

Diagnostic Air Quality Model Evaluation of Source-Specific Primary and Secondary Fine Particulate Carbon

Science.gov (United States)

Ambient measurements of 78 source-specific tracers of primary and secondary carbonaceous fine particulate matter collected at four midwestern United States locations over a full year (March 2004–February 2005) provided an unprecedented opportunity to diagnostically evaluate...

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.

A randomized comparison of a novel nitinol-frame low-dose-copper intrauterine contraceptive and a copper T380S intrauterine contraceptive.

Science.gov (United States)

Reeves, Matthew F; Katz, Bob H; Canela, Juan M; Hathaway, Mark J; Tal, Michael G

2017-06-01

We sought to compare VeraCept (VC175), a novel nitinol intrauterine contraceptive (IUC) with 175 square-mm of copper surface area, to a copper T380S IUC. We enrolled parous women into a randomized subject-blinded comparison of VC175 and a copper T380S in a 2:1 fashion at a single clinic. The primary outcomes were total adverse events and continuation at 12 months. We also examined pain on insertion, ease of placement, expulsion, tolerability and pregnancy. Subjective ratings were on a 5-point Likert scale (0, no pain to 5, worst pain). We followed subjects through 24-month follow-up. We enrolled 300 women with 199 randomized to VC175 and 101 to the T380S. Insertion was successful in 198 subjects for VC175 and 100 for the T380S. Mean age was 25 years (range 18, 41), and median parity was 2 (range 1, 8), with 39% having only had Cesarean deliveries. No subjects developed clinical infection or reported serious adverse events. In the VC175 and T380S groups, mean pain at insertion was 1.4 and 2.4, respectively (p<.01). At the 12-month primary endpoint for VC175 and T380S, respectively, continuation was 84% and 68% (p<.002) with expulsions in 5.0% and 12.0% (p<.05) and removal for pain/bleeding in 3.5% and 17.0% (p<.01). At the 24-month visit for VC175 and T380S, respectively, continuation was 77% and 62% (p<.02 by log-rank). One ectopic pregnancy was identified at the 12-month follow-up in a VC175 user. No other pregnancies were diagnosed. With 297.3 and 132.4 woman-years, pregnancy rates were 0.3 and 0.0 per 100 woman-years for VC175 and T380S, respectively. VC175 resulted in less pain at insertion, fewer expulsions and higher total continuation than the T380S, with similar contraceptive efficacy. VC175 is a promising new intrauterine copper contraceptive on a nitinol frame that warrants further clinical trials. Copyright © 2017 Elsevier Inc. All rights reserved.

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

Science.gov (United States)

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

2017-01-01

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

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

International Nuclear Information System (INIS)

Marcos, N.

1996-10-01

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

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

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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.

Utilization of supplemental methionine sources by primary cultures of chick hepatocytes

International Nuclear Information System (INIS)

Dibner, J.J.

1983-01-01

Utilization of 2-hydroxy-4-(methylthio) butanoic acid (HMB) as a substrate for protein synthesis was studied by using primary cultures of chick liver cells. Cultures were prepared by enzymatic dissociation of livers from week old Hubbard broiler chicks and were maintained for 4 days under nonproliferative conditions. Hepatocyte differentiation was verified by using dexamethasone induction of tyrosine aminotransferase activity. Conversion of [14C]HMB to L-methionine was shown by chromatographic analysis of hepatocyte protein hydrolysate and incorporation into protein was proven by cycloheximide inhibition of synthesis. When incorporation of HMB was compared to that of DL-methionine (DLM) equimolar quantities of the two sources were found in liver cell protein. These results support, at a cellular level, the conclusion that HMB and DLM are biochemically equivalent sources of methionine for protein synthesis

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).

Long term energy-related environmental issues of copper production

Energy Technology Data Exchange (ETDEWEB)

Alvarado, S. [University of Chile, Santiago (Chile). Dept. of Mechanical Engineering; Maldonado, P.; Barrios, A.; Jaques, I. [University of Chile, Santiago (Chile). Energy Research Program

2002-02-01

Primary copper production is a major activity in the mining sector of several countries. However, it is highly energy-intensive and poses important environmental hazards. In the case of Chile, the world's largest copper producer (40% of world total), we examine its energy consumption and energy-related environmental implications over a time horizon of 25 years. Concerning the latter, we focus on greenhouse-gas (GHG) emissions, one of the most debated environmental issues. This paper follows up our previous report in which the current situation was analyzed and a particular technical option for improving the energy efficiency and concurrently reducing GHG emissions was discussed. Estimated reference or base (BS) and mitigation (MS) scenarios are developed for the period ending in 2020. The former assesses the energy demand projected in accordance with production forecasts and specific energy consumption patterns (assuming that energy efficiency measures are adopted 'spontaneously') with their resultant GHG emissions, while the latter assumes induced actions intended to reduce emissions by adopting an aggressive policy of efficient energy use. For the year 2020, the main results are: (i) BS, 1214 t of CO{sub 2}/ton of refined copper content (49% lower than in 1994); (ii) MS, 1037 t of CO{sub 2}/t of refined copper content (56% lower than in 1994). CO{sub 2} emissions have been estimated considering both fuel and electricity process requirements. (author)

Determination of copper in some Myanmar indigenous medicines by neutron activation analysis

International Nuclear Information System (INIS)

Myint-U; Kyi Kyi San

1994-01-01

Copper was determined in two Myanmar indigenous medicines by neutron activation analysis using an Am(Be) radionuclide neutron source. The activity of 511 keV peak of the 64 Cu was measured. (author) 2 refs.; 2 tabs

Primary Sources: America's Teachers on Teaching in an Era of Change. Third Edition

Science.gov (United States)

Scholastic Inc. and the Bill & Melinda Gates Foundation, 2013

2013-01-01

This third edition of "Primary Sources" represents a joint project of Scholastic and the Bill & Melinda Gates Foundation. It reports the views of more than 20,000 public school teachers on important issues related to their profession. Fielded in July 2013, the survey asks teachers about their motivation, new learning standards,…

Analysis Of Coppers Market And Price-Focus On The Last Decades Change And Its Future Trend

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Eugie Kabwe

2015-08-01

Full Text Available Abstract it is important to analyse the major players within a copper supply chain as well as current market dynamics relevant international guidelines major impacts affecting the sustainability of the whole system and policy drivers affecting its price on the global market. Focusis on understanding major and provisional factors affecting copper price on themarketlong-term copper prices are determined by the fundamentals of supply and demand. Short term however are driven by financial market and other variables. Through analysis of the major factors and present market dynamics global copper consumption increased since 1970 regardless of the economic slump in 2007-2009 growth is likely to continuechiefly driven by increasing demand in China and India. Since 2004 the price of copper on the global market increased drastically its consumption was mainly concentrated in developed industrial countries. The economic situation of developed countries has a greater impact on copper prices addition of Asian nations increased urbanization and industrialization. Forecasts remain progressive asAsia advance with urbanization and industrializationplans. Anticipated to account for a major growth in global copper in the next 20 years will present a large task to double copper supply output. Urbanization and industrialization will continue to surge copper demand projected to overcome global copper production high demandbut lesser supply on the market.The decline of copper supply would cause a mountingdeficit in turn increase demand by 2025. Asias level of economic activity and urbanization is far from complete it will be a chief source of copper demand in the decades to come.

Austenitic stainless steels and high strength copper alloys for fusion components

International Nuclear Information System (INIS)

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

1998-01-01

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

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)

Interpreting stream sediment fingerprints against primary and secondary source signatures in agricultural catchments

Science.gov (United States)

Blake, Will H.; Haley, Steve; Smith, Hugh G.; Taylor, Alex; Goddard, Rupert; Lewin, Sean; Fraser, David

2013-04-01

Many sediment fingerprinting studies adopt a black box approach to source apportionment whereby the properties of downstream sediment are compared quantitatively to the geochemical fingerprints of potential catchment sources without consideration of potential signature development or modification during transit. Working within a source-pathway-receptor framework, this study aimed to undertake sediment source apportionment within 6 subcatchments of an agricultural river basin with specific attention to the potential role of contaminants (vehicle emissions and mine waste) in development of stream sediment signatures. Fallout radionuclide (FRN) and geochemical fingerprinting methods were adopted independently to establish source signatures for primary sediment sources of surface and subsurface soil materials under various land uses plus reworked mine and 'secondary' soil material deposited, in transit, along road networks. FRN data demonstrated expected variability between surface soil (137Cs = 14 ± 3 Bq kg-1; 210Pbxs = 40 ± 7 Bq kg-1) and channel bank materials (137Cs = 3 ± 1 Bq kg-1; 210Pbxs = 24 ± 5 Bq kg-1) but road transported soil material was considerably elevated in 210Pbxs (up to 673 ± 51 Bq kg-1) due to sediment interaction with pluvial surface water within the road network. Geochemical discrimination between surface and subsurface soil materials was dominated by alkaline earth and alkali metals e.g. Ba, Rb, Ca, K, Mg which are sensitive to weathering processes in soil. Magnetic susceptibility and heavy metals were important discriminators of road transported material which demonstrated transformation of the signatures of material transported via the road network. Numerical unmixing of stream sediment indicated that alongside channel bank erosion, road transported material was an important component in some systems in accord with FRN evidence. While mining spoil also ranked as a significant source in an affected catchment, perhaps related to legacy

Copper: From neurotransmission to neuroproteostasis

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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.

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

Determination of copper in some Myanmar indigenous medicines by neutron activation analysis

Energy Technology Data Exchange (ETDEWEB)

Myint-U,; San, Kyi Kyi [Yangon Univ. (Myanmar). Dept. of Chemistry

1994-09-15

Copper was determined in two Myanmar indigenous medicines by neutron activation analysis using an Am(Be) radionuclide neutron source. The activity of 511 keV peak of the [sup 64]Cu was measured. (author) 2 refs.; 2 tabs.

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.

The Pedagogy of Primary Historical Sources in Mathematics: Classroom Practice Meets Theoretical Frameworks

Science.gov (United States)

Barnett, Janet Heine; Lodder, Jerry; Pengelley, David

2014-01-01

We analyze our method of teaching with primary historical sources within the context of theoretical frameworks for the role of history in teaching mathematics developed by Barbin, Fried, Jahnke, Jankvist, and Kjeldsen and Blomhøj, and more generally from the perspective of Sfard's theory of learning as communication. We present case studies…

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,

Plastic deformation mechanism of polycrystalline copper foil shocked with femtosecond laser

International Nuclear Information System (INIS)

Ye, Y.X.; Feng, Y.Y.; Lian, Z.C.; Hua, Y.Q.

2014-01-01

Plastic deformation mechanism of polycrystalline copper foil shocked with femtosecond (fs) laser has been characterized through optical microscopy (OM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Experiments of ns laser shocking copper (Cu) and fs laser shocking aluminum (Al) were also conducted for comparison. Dislocations arranged in multiple forms, profuse twins and stacking faults (SFs) coexist in the fs laser shocked copper. At small strain condition, dislocation slip is the dominant deformation mode and small amount of SFs act as complementary mechanism. With strain increasing, profuse twins and SFs form to accommodate the plastic deformation. Furthermore, new formed SFs incline to locate around the old ones because the dislocation densities there are more higher. So there is a high probability for new SFs overlapping on old ones to form twins, or connecting old ones to lengthen them, which eventually produce the phenomena that twins connect with each other or twins connect with SFs. Strain greatly influences the dislocation density. Twins and SFs are more dependent on strain rate and shock pressure. Medium stacking fault energy (SFE) of copper helps to extend partial dislocations and provides sources for forming SFs and twins.

Physical models and primary design of reactor based slow positron source at CMRR

Science.gov (United States)

Wang, Guanbo; Li, Rundong; Qian, Dazhi; Yang, Xin

2018-07-01

Slow positron facilities are widely used in material science. A high intensity slow positron source is now at the design stage based on the China Mianyang Research Reactor (CMRR). This paper describes the physical models and our primary design. We use different computer programs or mathematical formula to simulate different physical process, and validate them by proper experiments. Considering the feasibility, we propose a primary design, containing a cadmium shield, a honeycomb arranged W tubes assembly, electrical lenses, and a solenoid. It is planned to be vertically inserted in the Si-doping channel. And the beam intensity is expected to be 5 ×109

A copper-mediated reverse aromatic Finkelstein reaction in ionic liquid

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Anh T.H. Nguyen

2018-03-01

Full Text Available We have developed a general method for reverse aromatic Finkelstein reactions. Good reaction yields were obtained when aryl iodides or aryl bromides were treated with copper halide salts as promoters in a 1-butyl-3-methylimidazolium bromide ([BMIM]Br ionic liquid (IL solvent at 140 °C for 8 h. Preliminary investigation supported that the copper salts were also the halide sources in halogen exchange reactions. The optimized conditions are applicable to a variety of substrates and have excellent functional group tolerance. Additionally, the [BMIM]Br solvent showed good stability for at least 10 consecutive runs. Results indicated that the [BMIM]Br solvent was recyclable for reverse aromatic Finkelstein reactions.

Catalysis of copper corrosion products on chlorine decay and HAA formation in simulated distribution systems.

Science.gov (United States)

Zhang, Hong; Andrews, Susan A

2012-05-15

This study investigated the effect of copper corrosion products, including Cu(II), Cu(2)O, CuO and Cu(2)(OH)(2)CO(3), on chlorine degradation, HAA formation, and HAA speciation under controlled experimental conditions. Chlorine decay and HAA formation were significantly enhanced in the presence of copper with the extent of copper catalysis being affected by the solution pH and the concentration of copper corrosion products. Accelerated chlorine decay and increased HAA formation were observed at pH 8.6 in the presence of 1.0 mg/L Cu(II) compared with that observed at pH 6.6 and pH 7.6. Further investigation of chlorine decay in the presence of both Suwannee River NOM and Cu(II) indicated that an increased reactivity of NOM with dissolved and/or solid surface-associated Cu(II), rather than chlorine auto-decomposition, was a primary reason for the observed rapid chlorine decay. Copper corrosion solids [Cu(2)O, CuO, Cu(2)(OH)(2)CO(3)] exhibited catalytic effects on both chlorine decay and HAA formation. Contrary to the results observed when in the absence of copper corrosion products, DCAA formation was consistently predominant over other HAA species in the presence of copper corrosion products, especially at neutral and high pH. This study improves the understanding for water utilities and households regarding chlorine residuals and HAA concentrations in distribution systems, in particular once the water reaches domestic plumbing where copper is widely used. Copyright © 2012 Elsevier Ltd. All rights reserved.

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.

Seasonal Shifts in Primary Water Source Type: A Comparison of Largely Pastoral Communities in Uganda and Tanzania

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Amber L. Pearson

2016-01-01

Full Text Available Many water-related illnesses show an increase during the wet season. This is often due to fecal contamination from runoff, yet, it is unknown whether seasonal changes in water availability may also play a role in increased illness via changes in the type of primary water source used by households. Very little is known about the dynamic aspects of access to water and changes in source type across seasons, particularly in semi-arid regions with annual water scarcity. The research questions in this study were: (1 To what degree do households in Uganda (UG and Tanzania (TZ change primary water source type between wet and dry seasons?; and (2 How might seasonal changes relate to water quality and health? Using spatial survey data from 92 households each in UG and TZ this study found that, from wet to dry season, 26% (UG and 9% (TZ of households switched from a source with higher risk of contamination to a source with lower risk. By comparison, only 20% (UG and 0% (TZ of households switched from a source with lower risk of contamination to a source with higher risk of contamination. This research suggests that one pathway through which water-related disease prevalence may differ across seasons is the use of water sources with higher risk contamination, and that households with access to sources with lower risks of contamination sometimes choose to use more contaminated sources.

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

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

Non destructive examination of primary wall small scale mock-up DS-1F

International Nuclear Information System (INIS)

Jeskanen, H.; Lahdenperae, K.; Kauppinen, P.; Taehtinen, S.

1998-06-01

Ultrasonic examination of primary wall small scale mock up DS-1F before thermal testing showed no major defects on studied interfaces. However, some small indications were found on copper to copper and copper to steel interfaces and surface roughness of the outer surface of copper layer gave clear indications on ultrasonic images. After thermal test a curved 50 mm long crack along the Y- direction in the middle of the heated surface of the mock up and a 220 mm long crack along the copper to copper interface on the side surface of the mock up were detected. Small cracks, less than 60-80 μm in depth, were observed on copper surface. After thermal test the corresponding ultrasonic examination showed a strong effect on ultrasonic attenuation properties and on leaky Rayleigh waves on outer surface of copper layer. A major indication was found on copper to copper interface. About 50% of the copper to copper interface was delaminated. However, some small indications found already before thermal test were also found after thermal test and they were not grown in size. No indications were observed on copper to stainless steel interfaces. Additionally, major indications were found on stainless steel tube to copper interfaces. Tubes No. 1 and 2 were almost completely whereas tube No. 3 only partly separated from copper. No indications were found on stainless steel tube to copper interface on tube No. 4. Eddy current measurements showed no volumetric or crack like flaws in the stainless steel tubes, however, delamination of the copper to copper interface along the tubes No. 1, 2 and 3 was observed. (orig.)

Adsorption of copper onto char derived macro alga, Undaria pinnatifida

International Nuclear Information System (INIS)

Cho, Hye Jung; Ko, Jeong Huy; Heo, Hyeon Su; Park, Hye Jin; BAe, Yoon Ju; Kim, Jung Hwan; Park, Young-Kwon

2010-01-01

Full text: A release of heavy metals into the environment by industrial activities raises much environmental problems because they tend to remain indefinitely, circulating and eventually accumulating throughout the food chain. Copper is essential to human life and health but, like all heavy metals, is potentially toxic as well. The excessive intakes of copper result in its accumulation in the liver and produce gastrointestinal problems, kidney damage, anemia, and continued inhalation of copper-containing sprays is linked with an increase in lung cancer among exposed people. Consequently, we need to eliminate the copper in drinking water. Also, growth rates of marine macro algae far exceed those of terrestrial biomass, without water limitations, so annual primary production rates are higher for the major marine macro algae than for most terrestrial biomass. According to these reasons, we try to use the macro alga, Undaria pinnatifida. Adsorption of heavy metals is one of the possible technologies involved in the removal of toxic metals from industrial waste streams and mining waste water using low-cost adsorbents. In recent years, many low-cost adsorbents such as seaweeds, activated carbon, etc. have been investigated, but the char by macro alga, Undaria pinnatifida, have not proven to be the most effective and promising substrates. The aim of this study is to remove copper from its aqueous solution by Undaria pinnatifida char for various parameters like pH, contact time, and Cu(II) concentration. The adsorption capacity of Cu(II) by Undaria pinnatifida char was investigated as a function of pH, contact time, and Cu(II) concentration at room temperature. And it was verified using equilibrium studies. (author)

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.

A New Heterotrophic Strain for Bioleaching of Low Grade Complex Copper Ore

Directory of Open Access Journals (Sweden)

Kaijian Hu

2016-02-01

Full Text Available A new heterotrophic strain, named Providencia sp. JAT-1, was isolated and used in bioleaching of low-grade complex copper ore. The strain uses sodium citrate as a carbon source and urea as a nitrogen source to produce ammonia. The optimal growth condition of the strain is 30 C, initial pH 8, sodium citrate 10 g/L and urea 20 g/L, under which the cell density and ammonia concentration in the medium reached a maximum of 4.83 × 108 cells/mL and 14 g/L, respectively. Ammonia produced by the strain is used as the main lixiviant in bioleaching. Bioleaching results revealed that higher strain growth led to a higher copper recovery, while higher pulp density will cause a greater inhibitory effect on strain growth and ammonia production. The copper extraction reached the highest value of 54.5% at the pulp density of 1%. Malachite, chrysocolla and chalcocite are easy to leach out in this bioleaching system while chalcopyrite is difficult. Results of comparative leaching experiments show that bioleaching using JAT-1 is superior to ammonia leaching at the same condition. The metabolites produced by the strain other than ammonia are also involved in bioleaching.

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.

Compact and intense parametric x-ray radiation source based on a linear accelerator with cryogenic accelerating and decelerating copper structures

Science.gov (United States)

Hyun, J.; Satoh, M.; Yoshida, M.; Sakai, T.; Hayakawa, Y.; Tanaka, T.; Hayakawa, K.; Sato, I.; Endo, K.

2018-01-01

This paper describes a proposal for a compact x-ray source based on parametric x-ray radiation (PXR). The PXR, which is produced when a single crystal is bombarded with relativistic electrons, has good monochromaticity and spatial coherence, and is expected to be well suited for imaging of low-Z materials and medical application. The proposed system employs a pair of copper accelerating structures which are operated at a cryogenic temperature of 20 K and arranged to form a resonant ring configuration. The electron beam is once accelerated up to 75 MeV in one of the structures, being decelerated down to lower than 7 MeV in the other structure after generating PXR at a single crystal, and then dumped. The expected x-ray yield is 1 09 photons /s at a center energy of 15 keV or higher.

Copper hexacyanoferrate battery electrodes with long cycle life and high power

KAUST Repository

Wessells, Colin D.; Huggins, Robert A.; Cui, Yi

2011-01-01

Short-term transients, including those related to wind and solar sources, present challenges to the electrical grid. Stationary energy storage systems that can operate for many cycles, at high power, with high round-trip energy efficiency, and at low cost are required. Existing energy storage technologies cannot satisfy these requirements. Here we show that crystalline nanoparticles of copper hexacyanoferrate, which has an ultra-low strain open framework structure, can be operated as a battery electrode in inexpensive aqueous electrolytes. After 40,000 deep discharge cycles at a 17g-C rate, 83% of the original capacity of copper hexacyanoferrate is retained. Even at a very high cycling rate of 83g-C, two thirds of its maximum discharge capacity is observed. At modest current densities, round-trip energy efficiencies of 99% can be achieved. The low-cost, scalable, room-temperature co-precipitation synthesis and excellent electrode performance of copper hexacyanoferrate make it attractive for large-scale energy storage systems. © 2011 Macmillan Publishers Limited. All rights reserved.

Copper hexacyanoferrate battery electrodes with long cycle life and high power

KAUST Repository

Wessells, Colin D.

2011-11-22

Short-term transients, including those related to wind and solar sources, present challenges to the electrical grid. Stationary energy storage systems that can operate for many cycles, at high power, with high round-trip energy efficiency, and at low cost are required. Existing energy storage technologies cannot satisfy these requirements. Here we show that crystalline nanoparticles of copper hexacyanoferrate, which has an ultra-low strain open framework structure, can be operated as a battery electrode in inexpensive aqueous electrolytes. After 40,000 deep discharge cycles at a 17g-C rate, 83% of the original capacity of copper hexacyanoferrate is retained. Even at a very high cycling rate of 83g-C, two thirds of its maximum discharge capacity is observed. At modest current densities, round-trip energy efficiencies of 99% can be achieved. The low-cost, scalable, room-temperature co-precipitation synthesis and excellent electrode performance of copper hexacyanoferrate make it attractive for large-scale energy storage systems. © 2011 Macmillan Publishers Limited. All rights reserved.

Substrate considerations for graphene synthesis on thin copper films

International Nuclear Information System (INIS)

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

2012-01-01

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

Experimental investigation of thermal emittance components of copper photocathode

Directory of Open Access Journals (Sweden)

H. J. Qian

2012-04-01

Full Text Available With progress of photoinjector technology, thermal emittance has become the primary limitation of electron beam brightness. Extensive efforts have been devoted to study thermal emittance, but experiment results differ between research groups and few can be well interpreted. Besides the ambiguity of photoemission mechanism, variations of cathode surface conditions during cathode preparation, such as work function, field enhancement factor, and surface roughness, will cause thermal emittance differences. In this paper, we report an experimental study of electric field dependence of copper cathode quantum efficiency (QE and thermal emittance in a radio frequency (rf gun, through which in situ cathode surface parameters and thermal emittance contributions from photon energy, Schottky effect, and surface roughness are extracted. It is found the QE of a copper cathode illuminated by a 266 nm UV laser increased substantially to 1.5×10^{-4} after cathode cleaning during rf conditioning, and a copper work function of 4.16 eV, which is much lower than nominal value (4.65 eV, was measured. Experimental results also show a thermal emittance growth as much as 0.92  mm mrad/mm at 50  MV/m due to the cathode surface roughness effect, which is consistent with cathode surface morphology measurements.

Geochemical prospecting for copper and nickel in the Wulgai and Tor Tangi areas southeast of Hindubagh, Quetta Division, Pakistan

Science.gov (United States)

Stanin, S. Anthony; Wahid, M.A.; Khan, Shamsher

1975-01-01

Showings of magnetite, copper, and possible nickel mineralization in the Hindubagh chromite mining district are near Wulgai and Tor Tangi. Several hundred samples of clastic material from dry streambeds in these areas were sieved for the minus-80-mesh fraction and analyzed for copper using 2, 2'-biquinoline and for nickel using alpha-furildioxime. The copper threshold is 75 ppm, and the nickel threshold is 400 ppm. A geochemical map has been prepared that shows nine areas of anomalously high copper and six areas of high nickel. The nickel anomalies may represent secondary dispersion patterns derived from the erosion of nickeliferous ultramafic rocks of the Hindubagh intrusive complex. Copper showings in and near four of the anomalous copper areas indicate that detailed geological investigation and detailed geochemical sampling of rocks, soil, and unconsolidated clastic material are required to determine the source of the anomalies.

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.

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

Directory of Open Access Journals (Sweden)

Stevanović Z.

2009-01-01

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

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

Nuclear Spectroscopy with Copper Isotopes of Extreme N/Z Ratios

CERN Multimedia

La commara, M; Roeckl, E; Van duppen, P L E; Schmidt, K A; Lettry, J

2002-01-01

The collaboration aims to obtain detailed nuclear spectroscopy information on isotopes close to the magic proton number Z=28 Very neutron-rich and neutron-deficient copper isotopes are ionized with the ISOLDE resonance ionization laser ion source (RILIS) to provide beams with low cross contamination.\\\\ \\\\On the neutron-deficient side the high $Q_\\beta$-values of $^{56}$Cu (15~MeV) and $^{57}$Cu (8.8~MeV) allow to study levels at high excitation energies in the doubly magic nucleus $^{56}$Ni and the neighbouring $^{57}$Ni. On the neutron-rich side the spectroscopy with separated copper isotopes allows presently the closest approach to the doubly magic $^{78}$Ni at an ISOL facility. Up to now no suitable target material with a rapid release was found for nickel itself. A slow release behaviour has to be assumed also for the chemically similar elements iron and cobalt.\\\\ \\\\Using a narrow-bandwidth dye laser and tuning of the laser frequency allows to scan the hyperfine splittings of the copper isotopes and isome...

Natural environment in the area of copper smelter plants. Trend of changes

Directory of Open Access Journals (Sweden)

Łucja Strzelec

2012-06-01

Full Text Available Findings of air quality are brought forward in the area of copper industry impact with particular attention paid to copper smelter plants located in Legnica and Głogów area covering the period from 1980 to 2010. The paper identifies occurring changes and trends in the course of years. Lowering of dust-gaseous emissions from the most crucial sources in the area of LegnicaGłogów Copper Mining Region improved air quality in this region in the significant way. The fact is also of some importance that emission of pollutants from big sources combusting fuels for energy generation was reduced either by rundown of production or liquidation of some plants. Based on the conducted state environmental monitoring it is concluded that at present emission of pollutants from industrial sources affects air quality to a lesser degree. There are still problems of air protection waiting to be solved which are connected with: – emission of gaseous-dust pollutants from domestic-municipal sector i. e. so called low emission from individual heating of dwellings. The sources are low emitters where often coal is combusted together with various types of waste. Therefore after starting the period of centrally heated dwellings air quality monitoring stations recorded evidently the increase of dust and gaseous pollutants including benzo (a pirene. – pollutants emission from road transport which is the cause of high concentration of nitrogen oxides, carbon monoxide and hydrocarbons particularly in the vicinity of roads and streets of big road traffic density. Materials and methods: The base of the study were findings obtained from District Inspectorate of Environmental Protection in Legnica in the framework of carried out since 1991 the state environmental monitoring in national, regional and local network. In the period from 1980 till 1990 the studies performed Research Centre of Environmental Control in Legnica.

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

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

Heavy metal pollution among autoworkers. II. Cadmium, chromium, copper, manganese, and nickel

Energy Technology Data Exchange (ETDEWEB)

Clausen, J.; Rastogi, S.C.

1977-08-01

Garages and auto-repair workshops may be polluted with other heavy metals besides lead. Blood of autoworkers with high lead content was analyzed for cadmium, chromium, copper, manganese, nickel, ALAD activity and carboxyhaemoglobin level. Cadmium and copper levels in blood of autoworkers were comparable with those of the control subjects while chromium and nickel levels were significantly higher (P < 0.01 for both metals), and scattered raised values of manganese were found. There was no significant mutual correlation between levels of various heavy metals determined in whole blood. High copper levels were slightly related to decreasing ALAD activity (P < 0.1). Nineteen percent of autoworkers were found to have an abnormally high blood level of carboxyhemoglobin. The amount of particulate heavy metal in autoworkshop air was not related to biochemical abnormalities found in the autoworkers. Various sources of pollution of these heavy metals in autoworkshops are discussed.

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

Preferred orientation determination using line source x-ray diffraction

International Nuclear Information System (INIS)

Kimmel, G.; Shmarjahu, D.

1977-10-01

A texture goniometer has been attached to a diffractometer connected to a line-focus x-ray source. Reasonable results are obtained for the texture of rolled sheets and the test procedure is given. To illustrate the test procedure, the determination of preferred orientation in cold-rolled copper is described, as compared with random powder of sintered copper. Improvements of the measurements are proposed

Organic and inorganic sources of zinc, copper and selenium in diets for dairy cows: intake, blood metabolic profile, milk yield and composition

Directory of Open Access Journals (Sweden)

Cristina Simões Cortinhas

2012-06-01

Full Text Available The present study was carried out with the objective of evaluating the effects of feeding dairy cows with organic or inorganic sources of zinc (Zn, copper (Cu and selenium (Se on blood concentrations of these minerals, blood metabolic profiles, nutrient intake and milk yield and composition. Nineteen Holstein cows were selected and randomly assigned to two groups for receiving organic (n = 9 or inorganic (n = 10 sources of Zn, Cu and Se from 60 days before the expected date of calving to 80 days of lactation. Samples of feed, orts and milk were collected for analysis. Body condition score (BCS was determined and blood samples were collected for analysis of Zn, Cu and Se concentrations, as well as for metabolic profile. Supplying organic or inorganic sources of Zn, Cu, and Se did not affect dry matter and nutrient intake, blood metabolic profile, milk yield and composition, plasma concentration of these minerals, and BCS or change the BCS in cows from 60 days before the expected date of calving to 80 days of lactation. An effect of time was observed on all feed intake variables, plasma concentrations of Zn and Se, milk yield, milk protein content, BCS and change in BCS.

Yttrium recovery from primary and secondary sources: A review of main hydrometallurgical processes

Energy Technology Data Exchange (ETDEWEB)

Innocenzi, Valentina, E-mail: valentina.innocenzi1@univaq.it [Department of Industrial Engineering, of Information and Economy, University of L’Aquila, Via Giovanni Gronchi 18, Zona industriale di Pile, 67100 L’Aquila (Italy); De Michelis, Ida [Department of Industrial Engineering, of Information and Economy, University of L’Aquila, Via Giovanni Gronchi 18, Zona industriale di Pile, 67100 L’Aquila (Italy); Kopacek, Bernd [SAT, Austrian Society for Systems Engineering and Automation, Gurkasse 43/2, A-1140 Vienna (Austria); Vegliò, Francesco [Department of Industrial Engineering, of Information and Economy, University of L’Aquila, Via Giovanni Gronchi 18, Zona industriale di Pile, 67100 L’Aquila (Italy)

2014-07-15

Highlights: • Review of the main hydrometallurgical processes to recover yttrium. • Recovery of yttrium from primary sources. • Recovery of yttrium from e-waste and other types of waste. - Abstract: Yttrium is important rare earths (REs) used in numerous fields, mainly in the phosphor powders for low-energy lighting. The uses of these elements, especially for high-tech products are increased in recent years and combined with the scarcity of the resources and the environmental impact of the technologies to extract them from ores make the recycling waste, that contain Y and other RE, a priority. The present review summarized the main hydrometallurgical technologies to extract Y from ores, contaminated solutions, WEEE and generic wastes. Before to discuss the works about the treatment of wastes, the processes to retrieval Y from ores are discussed, since the processes are similar and derived from those already developed for the extraction from primary sources. Particular attention was given to the recovery of Y from WEEE because the recycle of them is important not only for economical point of view, considering its value, but also for environmental impact that this could be generated if not properly disposal.

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.

Isotope investigation of anodic slime movements in copper electrorefining baths

International Nuclear Information System (INIS)

Urbanski, T.; Kohman, L.; Strzelecki, M.; Chojecki, M.; Kaczynska, R.; Wieclaw, B.

1975-01-01

A method was developed and introduced for monitoring the movement of silver-containing anodic slimes in copper electrorefining baths. Radioactive 111 Ag was used as tracer and copper plates labelled with the tracer were inserted into the anodes. During electrorefining the slime produced was continuously marked by the tracer. The activity of 111 Ag was measured at various points inside the bath by sampling and continuously registered with the aid of integrators. It was found that more than 99 percent of the slime slipped to the bottom of the bath close to the anode surface and did not migrate even at highest electrolyte flow rates. Small quantities of suspended slime contained an insignificant concentration of silver and should not be a source of cathode contamination. (author)

Performance of water source heat pump system using high-density polyethylene tube heat exchanger wound with square copper wire

Directory of Open Access Journals (Sweden)

Xin Wen Zhang

2015-07-01

Full Text Available Surface water source heat pump system is an energy-efficient heat pump system. Surface water heat exchanger is an important part of heat pump system that can affect the performance of the system. In order to enhance the performance of the system, the overall heat transfer coefficient (U value of the water exchanger using a 32A square copper coiled high-density polyethylene tube was researched. Comparative experiments were conducted between the performance of the coiled high-density polyethylene tube and the 32A smooth high-density polyethylene tube. At the same time, the coefficient of performance of the heat pump was investigated. According to the result, the U value of the coiled tube was 18% higher than that of the smooth tube in natural convection and 19% higher in forced convection. The coefficient of performance of the heat pump with the coiled tube is higher than that with the smooth tube. The economic evaluation of the coiled tube was also investigated.

SEM–EDS analysis of copper, glass and iron recovered from the 1st century AD shipwreck site off Godawaya, Southern Sri Lanka

Digital Repository Service at National Institute of Oceanography (India)

Chandraratne, W.M.; Gaur, A.S.; Rao, B.R.; Bhushan, R.; Muthucumarana, R.; Manders, M.; Khedekar, V.D.; Dayananda, A.M.A.

contaminants8, thus indicating different source materials. During the Harappan times, Khetri mines of Rajast- han, India, had been a major source of copper in addition to Oman and UAE in the Gulf region9. The copper alloy in the present study is composed... to Godawaya, there are famous monasteries at Mahanavulupura and Ramba monastic complexes, which have been either exca- vated or thoroughly explored. Results of these studies indicate active maritime activity in the historical and medieval periods...

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.

3-dimensional numerical analysis of friction stir welding of copper and aluminum

Energy Technology Data Exchange (ETDEWEB)

Aleagha, M. E. Aalami; Hadi, Behzad; Shahbazi, Mohammad Ali [Dept. of Mechanical Engineering, School of Engineering, Razi University, Kermanshah (Iran, Islamic Republic of)

2016-08-15

A time dependent Eulerian thermal/material flow model of friction stir welding was developed and applied to the dissimilar joining of pure copper and aluminum 1050-H16 alloy to investigate the maximum penetration of base metals. Thermal and material flow analysis was done with the assumed velocity field in the stir zone and considering a thermal source of energy obtained from the both Coulomb type of friction and the loss of shear stress in a non-Newtonian viscous behavior of metal flow. The developed model was used to estimate temperature gradient and penetration of material under three different conditions of tool offset and compared with the experimental results. The model shows that the penetration of the base metals is closely related to tool offset. In all of the cases, the metal fixed in the advancing side is copper. Nevertheless, when considering tool offset in the copper side and also when considering tool offset in the aluminum side, penetrating metals are copper and aluminum, respectively. Also, the model shows that the maximum temperature achieved in the base metals significantly depends on the tool offset.

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

Primary and secondary organic aerosol origin by combined gas-particle phase source apportionment

Directory of Open Access Journals (Sweden)

M. Crippa

2013-08-01

Full Text Available Secondary organic aerosol (SOA, a prominent fraction of particulate organic mass (OA, remains poorly constrained. Its formation involves several unknown precursors, formation and evolution pathways and multiple natural and anthropogenic sources. Here a combined gas-particle phase source apportionment is applied to wintertime and summertime data collected in the megacity of Paris in order to investigate SOA origin during both seasons. This was possible by combining the information provided by an aerosol mass spectrometer (AMS and a proton transfer reaction mass spectrometer (PTR-MS. A better constrained apportionment of primary OA (POA sources is also achieved using this methodology, making use of gas-phase tracers. These tracers made possible the discrimination between biogenic and continental/anthropogenic sources of SOA. We found that continental SOA was dominant during both seasons (24–50% of total OA, while contributions from photochemistry-driven SOA (9% of total OA and marine emissions (13% of total OA were also observed during summertime. A semi-volatile nighttime component was also identified (up to 18% of total OA during wintertime. This approach was successfully applied here and implemented in a new source apportionment toolkit.

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...

Copper (II) Removal In Anaerobic Continuous Column Reactor System By Using Sulfate Reducing Bacteria

Science.gov (United States)

Bilgin, A.; Jaffe, P. R.

2017-12-01

Copper is an essential element for the synthesis of the number of electrons carrying proteins and the enzymes. However, it has a high level of toxicity. In this study; it is aimed to treat copper heavy metal in anaerobic environment by using anaerobic continuous column reactor. Sulfate reducing bacteria culture was obtained in anaerobic medium using enrichment culture method. The column reactor experiments were carried out with bacterial culture obtained from soil by culture enrichment method. The system is operated with continuous feeding and as parallel. In the first rector, only sand was used as packing material. The first column reactor was only fed with the bacteria nutrient media. The same solution was passed through the second reactor, and copper solution removal was investigated by continuously feeding 15-600 mg/L of copper solution at the feeding inlet in the second reactor. When the experiment was carried out by adding the 10 mg/L of initial copper concentration, copper removal in the rate of 45-75% was obtained. In order to determine the use of carbon source during copper removal of mixed bacterial cultures in anaerobic conditions, total organic carbon TOC analysis was used to calculate the change in carbon content, and it was calculated to be between 28% and 75%. When the amount of sulphate is examined, it was observed that it changed between 28-46%. During the copper removal, the amounts of sulphate and carbon moles were equalized and more sulfate was added by changing the nutrient media in order to determine the consumption of sulphate or carbon. Accordingly, when the concentration of added sulphate is increased, it is calculated that between 35-57% of sulphate is spent. In this system, copper concentration of up to 15-600 mg / L were studied.

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.

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

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)

The Nature and Use of Copper Reserve and Resource Data

Science.gov (United States)

Cox, Dennis P.; Wright, Nancy A.; Coakley, George J.

1981-01-01

production from deposits. This correlation can be used to predict roughly the potential production from undeveloped deposits. Large deposits annually produce relatively less metal per ton of copper contained than do medium and small deposits. Dividing reserves by annual production gives a depletion date for each copper mine. The sum of annual production capacity of all mines not yet depleted at any year of interest gives the minimum production capacity for that year. A graph of minimum production capacity by year combined with curves representing potential capacity from undeveloped identified resources can be compared with various demand scenarios to yield a measure of copper requirements from new sources. Since 1950 reserves have been developed in the United States at a rate of about 1 million tons of copper per year. Since 1960 the number of deposits developed per 10-year period has greatly increased without a commensurate increase in tonnage of copper. This is in part due to the fact that recent exploration successes have been increasingly represented by smaller and (or) lower grade deposits containing less metal.

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.

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.

Elevated copper levels during larval development cause altered locomotor behavior in the adult carabid beetle Pterostichus cupreus L. (Coleoptera: Carbidae)

DEFF Research Database (Denmark)

Bayley, M; Baatrup, E; Heimbach, U

1995-01-01

behavior of adult Pterostichus cupreus carabid beetles was quantified after being raised on copper-contaminated food and soil during larval development. Copper was found to have an acute toxic effect measured in larval mortality, to cause a slight increase in the developmental period of males......It is generally believed that copper causes changes in carabid communities indirectly by reducing food availability, because these animals are frequently found to have only slightly elevated metal contents even close to pollution sources. Using computer-centered video tracking, the locomotor......, but not to effect the emergence weights of adults of either sex. This toxic effect on the larvae was preserved through pupation to the surviving adults, which were normal in size and appearance, but displayed a dramatically depressed locomotor behavior. Copper analysis of these adults revealed that copper levels...

Heavy metals in the atmosphere coming from a copper smelter in Chile

Science.gov (United States)

Romo-Kröger, C. M.; Morales, J. R.; Dinator, M. I.; Llona, F.; Eaton, L. C.

The Chilean mine El Teniente is the world's largest underground copper mine. It operates a giant smelter at Caletones (34° 7' S, 70° 27' W) and we have found it is the major source of air contamination in the region. In August 1991 a special circumstance occurred due to a labor strike, with total cessation of activities. A time series analysis of airborne particles collected at a site about 13 km from the smelter was performed in a period including the strike. The PIXE method and other techniques were used to analyse fine (Elemental characterization of soil samples by radioactive source analysis demonstrated that this group of elements did not come from airborne soil dust. Cluster analyses of the interelement correlation matrices, resulting from PIXE data, showed one group (Si, K, Ca, Fe) with main origin in soil and another group (S, Cu, Zn, As) coming from the copper smelter.

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

Designing display primaries with currently available light sources for UHDTV wide-gamut system colorimetry.

Science.gov (United States)

Masaoka, Kenichiro; Nishida, Yukihiro; Sugawara, Masayuki

2014-08-11

The wide-gamut system colorimetry has been standardized for ultra-high definition television (UHDTV). The chromaticities of the primaries are designed to lie on the spectral locus to cover major standard system colorimetries and real object colors. Although monochromatic light sources are required for a display to perfectly fulfill the system colorimetry, highly saturated emission colors using recent quantum dot technology may effectively achieve the wide gamut. This paper presents simulation results on the chromaticities of highly saturated non-monochromatic light sources and gamut coverage of real object colors to be considered in designing wide-gamut displays with color filters for the UHDTV.

The contact heat conductance at diamond-OFHC copper interface with GaIn eutectic as a heat transfer medium

International Nuclear Information System (INIS)

Assoufid, L.; Khounsary, A.M.

1996-01-01

Results of an experimental study of the contact heat conductance across a single diamond crystal interface with OFHC copper (Cu) are reported. Gallium-indium (GaIn) eutectic was used as an interstitial material. Contact conductance data are important in the design and the prediction of the performance of x-ray diamond monochromators under high-heat-load conditions. Two sets of experiments were carried out. In one, the copper surface in contact with diamond was polished and then electroless plated with 1 μm of nickel, while in the other, the copper contact surface was left as machined. Measured average interface heat conductances are 44.7 ±8 W/cm 2 -K for nonplated copper and 23.0 ±3 W/cm 2 -K for nickel-plated copper. For reference, the thermal contact conductances at a copper-copper interface (without diamond) were also measured, and the results are reported. A typical diamond monochromator, 0.2 mm thick, will absorb about 44 W under a standard undulator beam at the Advanced Photon Source. The measured conductance for nickel-plated copper suggests that the temperature drop across the interface of diamond and nickel-plated copper, with a 20 mm 2 contact area, will be about 10 degree C. Therefore temperature rises are rather modest, and the accuracy of the measured contact conductances presented here are sufficient for design purposes

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.

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.

The mammalian phosphate carrier SLC25A3 is a mitochondrial copper transporter required for cytochrome c oxidase biogenesis.

Science.gov (United States)

Boulet, Aren; Vest, Katherine E; Maynard, Margaret K; Gammon, Micah G; Russell, Antoinette C; Mathews, Alexander T; Cole, Shelbie E; Zhu, Xinyu; Phillips, Casey B; Kwong, Jennifer Q; Dodani, Sheel C; Leary, Scot C; Cobine, Paul A

2018-02-09

Copper is required for the activity of cytochrome c oxidase (COX), the terminal electron-accepting complex of the mitochondrial respiratory chain. The likely source of copper used for COX biogenesis is a labile pool found in the mitochondrial matrix. In mammals, the proteins that transport copper across the inner mitochondrial membrane remain unknown. We previously reported that the mitochondrial carrier family protein Pic2 in budding yeast is a copper importer. The closest Pic2 ortholog in mammalian cells is the mitochondrial phosphate carrier SLC25A3. Here, to investigate whether SLC25A3 also transports copper, we manipulated its expression in several murine and human cell lines. SLC25A3 knockdown or deletion consistently resulted in an isolated COX deficiency in these cells, and copper addition to the culture medium suppressed these biochemical defects. Consistent with a conserved role for SLC25A3 in copper transport, its heterologous expression in yeast complemented copper-specific defects observed upon deletion of PIC2 Additionally, assays in Lactococcus lactis and in reconstituted liposomes directly demonstrated that SLC25A3 functions as a copper transporter. Taken together, these data indicate that SLC25A3 can transport copper both in vitro and in vivo . © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

“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

Photoluminescence of Copper-Doped Lithium Niobate Crystals

Science.gov (United States)

Gorelik, V. S.; Pyatyshev, A. Yu.; Sidorov, N. V.

2018-05-01

The photoluminescence (PL) of copper-doped lithium niobate single crystals is studied using different UV-Vis light-emitting diodes and a pulse-periodic laser with a wavelength of 266 nm as excitation radiation sources. With the resonance excitation from a 527-nm light-emitting diode, the intensity of PL increases sharply (by two orders of magnitude). When using a 467-nm light-emitting diode for excitation, the PL spectrum is characterized by the presence of multiphonon lines in the range of 520-620 nm.

Geochemical Characterization of Copper Tailings after Legume Revegetation

Directory of Open Access Journals (Sweden)

Justine Perry T. Domingo

2014-12-01

Full Text Available Knowledge on the geochemistry of mine tailings is important in understanding the challenges in establishing vegetation cover on tailings dumps and mined out areas. In this study, the mineralogy and trace element composition of copper tailings were examined. Two legume species, Calopogonium mucunoides and Centrosema molle, were utilized to investigate the possible effects of these plants in the geochemical development of mine tailings into soil-like material. The initial mineralogical and chemical analysis of the tailings samples indicated poor conditions for plant growth—minimal levels of major nutrients and organic matter as well as elevated copper concentrations. Despite these conditions, the two legume species exhibited good growth rates. Both legumes have likewise signif icantly reduced heavy metal concentrations in the tailings, indicating the possibility of metal hyperaccumulation in the plant tissue. The mineral composition has been retained even after revegetation; nevertheless, breakdown of primary minerals and subsequent formation of clay minerals were detected. These results provide insights on the transformation of toxic materials into habitable substrates for sustained plant growth.

Characterization of the recombinant copper chaperone (CCS) from the plant Glycine (G.) max.

Science.gov (United States)

Sagasti, Sara; Yruela, Inmaculada; Bernal, Maria; Lujan, Maria A; Frago, Susana; Medina, Milagros; Picorel, Rafael

2011-02-01

The goal of the present work was to characterize the recombinant copper chaperone (CCS) from soybean. Very little is known about plant copper chaperones, which makes this study of current interest, and allows for a comparison with the better known homologues from yeast and humans. To obtain sizeable amounts of pure protein suitable for spectroscopic characterization, we cloned and overexpressed the G. max CCS chaperone in E. coli in the presence of 0.5 mM CuSO(4) and 0.5 mM ZnSO(4) in the broth. A pure protein preparation was obtained by using two IMAC steps and pH gradient chromatography. Most of the proteins were obtained as apo-form, devoid of copper atoms. The chaperone showed a high content (i.e., over 40%) of loops, turns and random coil as determined both by circular dichroism and homology modelling. The homology 3-D structural model suggests the protein might fold in three structural protein domains. The 3-D model along with the primary structure and spectroscopic data may suggest that copper atoms occupy the two metal binding sites, MKCEGC and CTC, within the N-terminal domain I and C-terminal domain III, respectively. But only one Zn-binding site was obtained spectroscopically.

A TEMPO-free copper-catalyzed aerobic oxidation of alcohols.

Science.gov (United States)

Xu, Boran; Lumb, Jean-Philip; Arndtsen, Bruce A

2015-03-27

The copper-catalyzed aerobic oxidation of primary and secondary alcohols without an external N-oxide co-oxidant is described. The catalyst system is composed of a Cu/diamine complex inspired by the enzyme tyrosinase, along with dimethylaminopyridine (DMAP) or N-methylimidazole (NMI). The Cu catalyst system works without 2,2,6,6-tetramethyl-l-piperidinoxyl (TEMPO) at ambient pressure and temperature, and displays activity for un-activated secondary alcohols, which remain a challenging substrate for catalytic aerobic systems. Our work underscores the importance of finding alternative mechanistic pathways for alcohol oxidation, which complement Cu/TEMPO systems, and demonstrate, in this case, a preference for the oxidation of activated secondary over primary alcohols. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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.

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

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

Directory of Open Access Journals (Sweden)

Ie. P. Prekrasna

2015-10-01

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

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.

Nucleation and growth of copper oxide films in MOCVD processes using the β-ketoiminate precursor 4,4'-(1,2-ethanediyldinitrilo)bis(2-pentanonate) copper(II)

International Nuclear Information System (INIS)

Condorelli, G.G.; Malandrino, G.; Fragala, I.L.

1999-01-01

The MOCVD of CuO has attracted much attention because of its application in high-T c superconducting films and gas sensors. This work focuses on the potential of a β-ketoiminate copper complex as an alternative MOCVD source to β-diketonate complexes. Particular attention has been given to factors such as texturing, roughness, and grain size of the deposit. (orig.)

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.

Elevated copper levels during larval development cause altered locomotor behavior in the adult carabid beetle Pterostichus cupreus L. (Coleoptera: Carbidae)

DEFF Research Database (Denmark)

Bayley, M; Baatrup, E; Heimbach, U

1995-01-01

It is generally believed that copper causes changes in carabid communities indirectly by reducing food availability, because these animals are frequently found to have only slightly elevated metal contents even close to pollution sources. Using computer-centered video tracking, the locomotor......, but not to effect the emergence weights of adults of either sex. This toxic effect on the larvae was preserved through pupation to the surviving adults, which were normal in size and appearance, but displayed a dramatically depressed locomotor behavior. Copper analysis of these adults revealed that copper levels...

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.

Contribution to the study of the chemical effects of the (n, γ) reaction on copper N-benzoyl N-phenyl hydroxylaminate and copper N-benzoyl N-(o) Tolyl hydroxylaminate

International Nuclear Information System (INIS)

Nakanishi, C.

1987-01-01

The influence of some factors such as pre-heating and pre-irradiation with gamma rays on the retention and thermal annealing of copper N-benzoyl N-phenyl hydroxylaminate and of copper N-benzolyl N-(o) tolyl hydroxylaminate is studied. The complexes were synthesized and characterized by determination of the melting-point, elemental analysis, X-ray diffraction, infra-red and visible range absoption spectrometry-thermogravimetric analysis were examined and the stability of the compounds was checked against heating and gamma irradiation from a 60 Co source. Some experiments using the Szilard-Chalmers effect were carried out by irradiating the compound in the IEA-R 1 nuclear reactor and calculating its specific activities. (M.J.C.) [pt

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.

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

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...

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

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.

Copper based anodes for bio-ethanol fueled low-temperature solid oxide fuel cells

Energy Technology Data Exchange (ETDEWEB)

Kondakindi, R.R.; Karan, K. [Queen' s Univ., Kingston, ON (Canada)

2003-07-01

Laboratory studies have been conducted to develop a low-temperature solid oxide fuel cell (SOFC) fueled by bio-ethanol. SOFCs are considered to be a potential source for clean and efficient electricity. The use of bio-ethanol to power the SOFC contributes even further to reducing CO{sub 2} emissions. The main barrier towards the development of the proposed SOFC is the identification of a suitable anode catalyst that prevents coking during electro-oxidation of ethanol while yielding good electrical performance. Copper was selected as the catalyst for this study. Composite anodes consisting of copper catalysts and gadolinium-doped ceria (GDC) electrolytes were prepared using screen printing of GDC and copper oxide on dense GDC electrolytes and by wet impregnation of copper nitrate in porous GDC electrolytes followed by calcination and sintering. The electrical conductivity of the prepared anodes was characterized to determine the percolation threshold. Temperature-programmed reduction and the Brunner Emmett Teller (BET) methods were used to quantify the catalyst dispersion and surface area. Electrochemical performance of the single-cell SOFC with a hydrogen-air system was used to assess the catalytic activities. Electrochemical Impedance Spectroscopy was used to probe the electrode kinetics.

Analysis of the primary source term for meltdown accidents using MELCOR 1.8.2

International Nuclear Information System (INIS)

Schmuck, P.

1995-01-01

The MELCOR code describing accident phenomena in the core and primary systems was used for source term calculations and - in the context of the MELCOR Cooperative Assessment Programme - for studying two-phase flows through components such as valves and chokes. Results of the latter studies in comparison to experiments gave hints for an improved calculation of momentum transfer between the phases. (orig.)

Physics and national socialism an anthology of primary sources

CERN Document Server

1996-01-01

This anthology of primary sources is a collection of 121 documents in English translation portraying the role of physics, both perceived and actual, in the Nazi state. These texts were written predominantly by influential German scientists, particularly physicists, both inside and outside Germany in the period from 1933 to 1945. The semipopular articles, private correspondence, and official memoranda selected for the volume reflect the contemporary developments in science as well as the change in political climate and working conditions after the National Socialists' rise to power. The extensive annotation is clearly distinguished from the original text, and the appendix provides an aid to the reader with biographical information on the more important figures and brief outlines of frequently mentioned institutions, journals and companies. The introduction surveys the latest results in the secondary literature.   ------    (…) the envisaged audience includes not only scholars and students of science, hist...

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.

The analysis of beryllium-copper diffusion joint after HHF test

International Nuclear Information System (INIS)

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

1995-01-01

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

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.

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.

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.

The Impact of Commodity Price Shocks in a Major Producing Economy. The Case of Copper and Chile

OpenAIRE

Michael Pedersen

2015-01-01

The present study analyzes how copper price shocks affect macroeconomic variables in Chile, which is the largest producer in the world of this commodity. It is taken into account that shocks with different sources may have different impacts and a separation is made between supply, demand, and specific copper demand shocks. The empirical analysis is based on a structural VAR model, where shocks are identified by sign restrictions, i.e. restrictions are imposed on impulse-response functions. In...

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.

Copper(I) mediated cross-coupling of amino acid derived organozinc reagents with acid chlorides

DEFF Research Database (Denmark)

Hjelmgaard, Thomas; Tanner, David Ackland

2006-01-01

This paper describes the development of a straightforward experimental protocol for copper-mediated cross-coupling of amino acid derived beta-amido-alkylzinc iodides 1 and 3 with a range of acid chlorides. The present method uses CuCN center dot 2LiCl as the copper source and for organozinc reagent...... 1 the methodology appears to be limited to reaction with more stable acid chlorides, providing the desired products in moderate yields. When applied to organozinc reagent 3, however, the protocol is more general and provides the products in good yields in all but one of the cases tested....

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.

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...

Local source impacts on primary and secondary aerosols in the Midwestern United States

Science.gov (United States)

Jayarathne, Thilina; Rathnayake, Chathurika M.; Stone, Elizabeth A.

2016-04-01

Atmospheric particulate matter (PM) exhibits heterogeneity in composition across urban areas, leading to poor representation of outdoor air pollutants in human exposure assessments. To examine heterogeneity in PM composition and sources across an urban area, fine particulate matter samples (PM2.5) were chemically profiled in Iowa City, IA from 25 August to 10 November 2011 at two monitoring stations. The urban site is the federal reference monitoring (FRM) station in the city center and the peri-urban site is located 8.0 km to the west on the city edge. Measurements of PM2.5 carbonaceous aerosol, inorganic ions, molecular markers for primary sources, and secondary organic aerosol (SOA) tracers were used to assess statistical differences in composition and sources across the two sites. PM2.5 mass ranged from 3 to 26 μg m-3 during this period, averaging 11.2 ± 4.9 μg m-3 (n = 71). Major components of PM2.5 at the urban site included organic carbon (OC; 22%), ammonium (14%), sulfate (13%), nitrate (7%), calcium (2.9%), and elemental carbon (EC; 2.2%). Periods of elevated PM were driven by increases in ammonium, sulfate, and SOA tracers that coincided with hot and dry conditions and southerly winds. Chemical mass balance (CMB) modeling was used to apportion OC to primary sources; biomass burning, vegetative detritus, diesel engines, and gasoline engines accounted for 28% of OC at the urban site and 24% of OC at the peri-urban site. Secondary organic carbon from isoprene and monoterpene SOA accounted for an additional 13% and 6% of OC at the urban and peri-urban sites, respectively. Differences in biogenic SOA across the two sites were associated with enhanced combustion activities in the urban area and higher aerosol acidity at the urban site. Major PM constituents (e.g., OC, ammonium, sulfate) were generally well-represented by a single monitoring station, indicating a regional source influence. Meanwhile, nitrate, biomass burning, food cooking, suspended dust, and

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.

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.

Photoinduced, copper-catalyzed alkylation of amides with unactivated secondary alkyl halides at room temperature.

Science.gov (United States)

Do, Hien-Quang; Bachman, Shoshana; Bissember, Alex C; Peters, Jonas C; Fu, Gregory C

2014-02-05

The development of a mild and general method for the alkylation of amides with relatively unreactive alkyl halides (i.e., poor substrates for SN2 reactions) is an ongoing challenge in organic synthesis. We describe herein a versatile transition-metal-catalyzed approach: in particular, a photoinduced, copper-catalyzed monoalkylation of primary amides. A broad array of alkyl and aryl amides (as well as a lactam and a 2-oxazolidinone) couple with unactivated secondary (and hindered primary) alkyl bromides and iodides using a single set of comparatively simple and mild conditions: inexpensive CuI as the catalyst, no separate added ligand, and C-N bond formation at room temperature. The method is compatible with a variety of functional groups, such as an olefin, a carbamate, a thiophene, and a pyridine, and it has been applied to the synthesis of an opioid receptor antagonist. A range of mechanistic observations, including reactivity and stereochemical studies, are consistent with a coupling pathway that includes photoexcitation of a copper-amidate complex, followed by electron transfer to form an alkyl radical.

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.

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

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.

Source identification of heavy metal contamination using metal association and Pb isotopes in Ulsan Bay sediments, East Sea, Korea

International Nuclear Information System (INIS)

Chae, Jung Sun; Choi, Man Sik; Song, Yun Ho; Um, In Kwon; Kim, Jae Gon

2014-01-01

Highlights: • The levels of Cu, Zn, and Pb in sediments were higher than the Korean TEL at one-third of all sites. • The primary source of metal contamination came from activities related to nonferrous metal refineries near Onsan Harbor. • Three different anthropogenic sources and background sediments could be identified as endmembers using Pb isotopes. • The major anthropogenic Pb sources were identified as imported ores from Australia and Peru. • Isotope ratios in anthropogenic Pb discharged from Ulsan Bay to offshore could be identified. - Abstract: To determine the characteristics of metal pollution sources in Ulsan Bay, East Sea, 39 surface and nine core sediments were collected within the bay and offshore area, and analyzed for metals and stable lead (Pb) isotopes. Most surface sediments (>95% from 48 sites) had high copper (Cu), zinc (Zn), cadmium (Cd), and Pb concentrations that were as much as 1.3 times higher than background values. The primary source of metal contamination came from activities related to nonferrous metal refineries near Onsan Harbor, and the next largest source was from shipbuilding companies located at the mouth of the Taehwa River. Three different anthropogenic sources and background sediments could be identified as end-members using Pb isotopes. Isotopic ratios for the anthropogenic Pb revealed that the sources were imported ores from Australia, Peru, and the United States. In addition, Pb isotopes of anthropogenic Pb discharged from Ulsan Bay toward offshore could be determined

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).

Choice of primary health care source in an urbanized low-income community in Singapore: a mixed-methods study.

Science.gov (United States)

Wee, Liang En; Lim, Li Yan; Shen, Tong; Lee, Elis Yuexian; Chia, Yet Hong; Tan, Andrew Yen Siong; Koh, Gerald Choon-Huat

2014-02-01

Cost and misperceptions may discourage lower income Singaporeans from utilizing primary care. We investigated sources of primary care in a low-income Singaporean community in a mixed-methods study. Residents of a low-income public rental flat neighbourhood were asked for sociodemographic details and preferred source of primary care relative to their higher income neighbours. In the qualitative component, interviewers elicited, from patients and health care providers, barriers/enablers to seeking care from Western-trained doctors. Interviewees were selected via purposive sampling. Transcripts were analyzed thematically, and iterative analysis was carried out using established qualitative method. Participation was 89.8% (359/400). Only 11.1% (40/359) preferred to approach Western-trained doctors, 29.5% (106/359) preferred alternative medicine, 6.7% (24/359) approached family/friends and 52.6% (189/359) preferred self-reliance. Comparing against higher income neighbours, rental flat residents were more likely to turn to alternative medicine and family members but less likely to turn to Western-trained doctors (P Self-reliance was perceived as acceptable for 'small' illnesses but not for 'big' ones, communal spirit was cited as a reason for consulting family/friends and social distance from primary care practitioners was highlighted as a reason for not consulting Western-trained doctors. Western-trained physicians are not the first choice of lower income Singaporeans for seeking primary care. Knowledge, primary care characteristics and costs were identified as potential barriers/enablers.

The role of protein crystallography in defining the mechanisms of biogenesis and catalysis in copper amine oxidase.

Science.gov (United States)

Klema, Valerie J; Wilmot, Carrie M

2012-01-01

Copper amine oxidases (CAOs) are a ubiquitous group of enzymes that catalyze the conversion of primary amines to aldehydes coupled to the reduction of O(2) to H(2)O(2). These enzymes utilize a wide range of substrates from methylamine to polypeptides. Changes in CAO activity are correlated with a variety of human diseases, including diabetes mellitus, Alzheimer's disease, and inflammatory disorders. CAOs contain a cofactor, 2,4,5-trihydroxyphenylalanine quinone (TPQ), that is required for catalytic activity and synthesized through the post-translational modification of a tyrosine residue within the CAO polypeptide. TPQ generation is a self-processing event only requiring the addition of oxygen and Cu(II) to the apoCAO. Thus, the CAO active site supports two very different reactions: TPQ synthesis, and the two electron oxidation of primary amines. Crystal structures are available from bacterial through to human sources, and have given insight into substrate preference, stereospecificity, and structural changes during biogenesis and catalysis. In particular both these processes have been studied in crystallo through the addition of native substrates. These latter studies enable intermediates during physiological turnover to be directly visualized, and demonstrate the power of this relatively recent development in protein crystallography.

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...

Adding silver and copper to hydrogen peroxide and peracetic acid in the disinfection of an advanced primary treatment effluent.

Science.gov (United States)

Orta De Velásquez, M T; Yáñez-Noguez, I; Jiménez-Cisneros, B; Luna Pabello, V M

2008-11-01

This paper evaluates the efficacy of hydrogen peroxide (HP) and peracetic acid (PAA) in the disinfection of an Advanced Primary Treatment (APT) effluent, and how said disinfection capacities can be enhanced by combining the oxidants with copper (Cu2+) and silver (Ag). The treatment sequence consisted of APT (adding chemicals to water to remove suspended solids by coagulation and flocculation), followed by disinfection with various doses of HP, HP+Cu2+, HP+Ag, PAA and PAA+Ag. Microbiological quality was determined by monitoring concentrations of fecal coliforms (FC), pathogenic bacteria (PB) and helminth eggs (HE) throughout the sequence. The results revealed that APT effluent still contains very high levels of bacteria as the treatment only removes 1-2 log of FC and PB, but the reduction in the number of viable helminth eggs was 83%. Subsequent disinfection stages demonstrated that both HP+Cu2+ and HP+Ag have a marked disinfection capacity for bacteria (3.9 and 3.4 log-inactivation, respectively). Peracetic acid on its own was already extremely efficient at disinfecting for bacteria, and the effect was enhanced when combining PAA with silver (PAA+Ag). The best result for HE removal was achieved by combining PAA with silver (PAA+Ag) at doses of 20 + 2.0 mg l(-1), respectively. The study concluded that the PAA+Ag and HP+Ag combinations were good alternatives for APT effluent disinfection, because the disinfected effluents met the standards in NOM-001-SEMARNAT-1996, Mexico's regulation governing the microbiological quality required in treated wastewater destined for unrestricted reuse in agricultural irrigation (disinfection treatments with a primary method such as APT, therefore, offers an effective and practical way of reducing the health risks normally associated with the reuse of wastewaters.

Toxicity of copper on the growth of marine microalgae Pavlova sp. and its chlorophyll-a

Science.gov (United States)

Purbonegoro, T.; Suratno; Puspitasari, R.; Husna, N. A.

2018-02-01

Marine microalgae is the primary producer at the base of the marine food chain. Their sensitivity to metal contamination provides important information for predicting the environmental impact of pollution. Toxicity testing using marine microalgae Pavlova sp. was carried out to assess the toxicity of copper on the growth and chlorophyll-a content. Results of this study show that adverse effects were observed by the increase of copper concentration. Cell number began to decrease at the lowest concentration (13 μg/L) and reduced drastically at 98 μg/L. Minimum cell number was observed at the highest concentration (890 μg/L). The inhibition concentration (IC50) value of copper for Pavlova sp. was 51.46 μg/L and at concentrations >29 μgL-1 the chlorophyll-a content decreased dramatically compared to the control. A variation in cell size and morphology was also observed at the higher concentration by the increase in the cell size and loss of setae compared to normal cells.

Study of the secondary negative ion emission of copper and several of its alloys by impact with Cs+ ions

International Nuclear Information System (INIS)

Vallerand, P.; Baril, M.

1977-01-01

Secondary ion emission studies have been undertaken using Cs + as the primary ion beam. A good vacuum (ca. 10 -8 torr) is needed to eliminate contamination by residual gases. Negative ion emission of pure copper is compared with its alloys. The thermodynamic equilibrium model of Andersen is discussed. For low element concentrations, the experimental data show enhancement in negative emission of P, Al, Fe, Sn, Ni, and attenuation for Zn, Pb. The order of magnitude of ionic efficiency S - for copper is evaluated at 10 -4 . (Auth.)

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.

Radiation Protection Aspects of Primary Water Chemistry and Source-term Management Report

International Nuclear Information System (INIS)

2014-04-01

Since the beginning of the 1990's, occupational exposures in nuclear power plant has strongly decreased, outlining efforts achieved by worldwide nuclear operators in order to reach and maintain occupational exposure as low as reasonably achievable (ALARA) in accordance with international recommendations and national regulations. These efforts have focused on both technical and organisational aspects. According to many radiation protection experts, one of the key features to reach this goal is the management of the primary system water chemistry and the ability to avoid dissemination of radioactivity within the system. It outlines the importance for radiation protection staff to work closely with chemistry staff (as well as operation staff) and thus to have sufficient knowledge to understand the links between chemistry and the generation of radiation field. This report was prepared with the primary objective to provide such knowledge to 'non-chemist'. The publication primarily focuses on three topics dealing with water chemistry, source term management and remediation techniques. One key objective of the report is to provide current knowledge regarding these topics and to address clearly related radiation protection issues. In that mind, the report prepared by the EGWC was also reviewed by radiation protection experts. In order to address various designs, PWRs, VVERs, PHWRs and BWRs are addressed within the document. Additionally, available information addressing current operating units and lessons learnt is outlined with choices that have been made for the design of new plants. Chapter 3 of this report addresses current practices regarding primary chemistry management for different designs, 'how to limit activity in the primary circuit and to minimise contamination'. General information is provided regarding activation, corrosion and transport of activated materials in the primary circuit (background on radiation field generation). Primary chemistry aspects that

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

Pollutant Source Tracking (PST) Technical Guidance

Science.gov (United States)

2011-12-01

in the context of heavy metals (lead, copper), is considered to be a minor process contribution to the source fingerprint. 3.7 RAPID SCREENING...limits (summarized in Table 2) support the use of ICP-AES (ICP-OES) for heavy metal determination in soils , sediments, wastewater and other matrices...are included here. Isotopic ratios of stable isotopes of the metal of interest can be used for source identification and apportionment in complex

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.

[Donor age affects on the «behavior» and the sensibility bone marrow cells in on copper ion of the primary culture].

Science.gov (United States)

Bozhkov, A I; Ohiienko, S L; Kuznetsova, Yu A; Bondar', A Yu; Marchenko, V P; Gumennaya, M S

2017-01-01

The changes of bone marrow cells (BMC) number in the primary culture from 0 to 96 hours, the pattern (the distribution of cells) of cells morphotypes and «lifespan» (the time of cell life after isolation) of myelocytes, metamyelocytes, band and segmented neutrophils, isolated of the young (3 months) and old (20months) animals, were investigated. The number of the BMC obtained from intact old animals increased faster in primary culture, than from young animals. The Cu induced fibrosis had different influence on the rate of BMC culture growth of old and young animals. The adding of 4 mM and 8 mM CuSO4x5H2O in the BMC culture of young and old animals resulted in a dose-dependent inhibition of growth rate of young animal cells. If copper ions were added into the culture of BMC of old animals, the decreased of the BMC number was described less than for cells of young animals. The adding of 8 mM CuSO4x5H2O inhibited proliferation less, than the adding of 4 mM CuSO4x5H2O. The Cu-induced liver fibrosis had accelerated the BMC rate death of both old and young animals. However, this effect was more pronounced in young animals. It is suggested, that during the ontogenesis the BMC undergo such epigenetic changes, which change functional properties.

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

Directory of Open Access Journals (Sweden)

Weiqi Leng

2017-06-01

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

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