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Macalady L. D., Smith S. K., Ranville F. J. Acid mine drainage; streambed sorption of copper, cadmium and zinc, Colorado Water Resources Research Institute, Completion Report , No. 154, 1990. Clement R. E., Eiceman G

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" 2 370 Farago, M. E. and Mullen, W. A. (1979): Plants which accumulate metals. IV. A possible copper proline complex from the roots of Armeria maritima. - Chim

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Introduction The study of the sorption of pyridine derivates by copper forms of synthetic zeolite ZSM5 and natural zeolite of the clinoptilolite type (CT) is a continuation of our previous study of copper forms of zeosorbents

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Abstract  

The sorption of copper on synthetic hydroxyapatite was investigated using a batch method and radiotracer technique. The hydroxyapatite sample prepared by a wet precipitation process was of high crystallinity with Ca/P ratio of 1.688. The sorption of copper on hydroxyapatite was pH independent ranging from 4 to 6 as a result of buffering properties of hydroxyapatite. The adsorption of copper was rapid and the percentage of Cu sorption was >98% during the first 15–30 min of the contact time. The experimental data for sorption of copper have been interpreted in the term of Langmuir isotherm. The sorption of Cu2+ ions was performed by ion-exchange with Ca2+ cations on the crystal surface of hydroxyapatite under experimental conditions. The competition effect of Zn2+, Fe2+ and Pb2+ towards Cu2+ sorption was stronger than that of Co2+, Ni2+ and Ca2+ ions. The ability of the bivalent cations to depress the sorption of copper on hydroxyapatite was in the following order Pb2+ > Fe2+ > Zn2+ > Co2+ ≈ Ni2+.

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Three commonly used medicinal plants, e.g., Adhatoda vasica, Cassia fistula, and Withania somnifera grown in two contrasting environmental conditions, namely from copper mining site and from control site corresponding to soil not contaminated with Cu, to understand correlations between high Cu bioaccumulation in medicinal plants on their antioxidant activities. Concentrations of some essential metals, e.g., Cr, Mn, Fe, Cu, Zn, and Se in the leaves of these plants were measured by instrumental neutron activation analysis. The Cu levels in the samples from mining site were in the range of 32.6 to 57.2 mg/kg, which were 5–7 folds higher than the control samples, while Cr levels were about 2-folds higher in the mining site. Speciation studies of Cr revealed negligible content of toxic hexavalent Cr. Antioxidant assay of these plants from both the sampling sites, measured as total phenolic content, total flavonoid content, 2,2′-diphenyl-1-picrylhydrazyl, free radical scavenging ability, and chelating ability with ferrous ions exhibited maximum activity for A. vasica, while that of W. somnifera was minimum. However, the variations in the antioxidant activities for each medicinal plant species from mining site and control site did not reveal significant differences.

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The oxidation of aliphatic thiols by air oxygen under mild conditions catalyzed by copper(II) complexes with amines (e.g. benzylamine) has been investigated. It was found that the reaction proceeds as a conjugated oxidation of both amines and thiols. The products of transformation of benzylamine have been identified. Copper(I) dodecanethiolate was synthesized for the first time, and its composition was determined. The thiolate is shown to be an intermediate of the process in the systems which demonstrate low activity. The intermediate in the most active systems is a mixed-ligand copper(II) complex containing both molecules of amine and thiolate anions in the coordination sphere.

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A method for the preconcentration of Cu(II) by cloud point extraction (CPE) followed by its determination using neutron activation analysis (NAA) was developed. The method involves the use of a nonionic surfactant, namely PONPE-7.5, and a chelating agent 1-(2-pyridylazo)-2-naphthol (PAN). The phase diagram of the surfactant was constructed and the effects of different additives on the cloud point were investigated. Factors, such as the solution pH, ionic strength, temperature, and concentrations of chelating agent and surfactant, which can influence the extraction efficiency of the metal, were optimized. The copper(II) chelate was extracted into a surfactant-rich phase of small volume with a recovery of nearly 100% and a preconcentration factor of 60. The small volume of the surfactant-rich phase obtained complies with the green chemistry concept, allowing the design of extraction procedures having lower toxicity than those using organic solvents. The method was applied to tap water samples.

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Certain bacterial strains can be employed in the removal of heavy metals from the environment. The aim of this study was to screen potential bacteria that were tolerant towards Cu and Cd and instrumental neutron activation analysis (INAA) was used to determine the concentrations of heavy metals in the sludge samples. The sludge samples from oil refinery plant in Malaysia contained Cr, Cs, Cu, Eu, Fe, Hg, Mn, Sb, Sc, Th, U and Zn. Seven bacterial isolates were identified to be tolerant to 100 mg/kg of copper and cadmium.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: E. Hoppe, E. Mintzer, C. Aalseth, D. Edwards, O. Farmer, J. Fast, D. Gerlach, M. Liezers, and H. Miley

Abstract  

Copper is one of few elements that have no long-lived radioisotopes and which can be electrodeposited to ultra-high levels of purity. Experiments probing neutrino properties and searching for direct evidence of dark matter require ultra-clean copper, containing the smallest possible quantities of radioactive contaminants. Important to the production of such copper is establishing the location and dispersion of contamination within the bulk material. Co-deposition of contaminants during copper electrodeposition and its relationship to nucleation and growth processes were investigated using scanning electron microscopy (SEM), laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), and secondary ionization mass spectrometry (SIMS).

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Abstract  

Spherical copper nanoparticles have been prepared by photo- or radiation-induced reduction of aqueous solutions containing 10−3 mol.dm−3 copper sulphate or formate, 1.3 mol.dm−3 propan-2-ol and polyvinyl alcohol as a stabilizer. Increase of initial copper concentration to 10−2 mol.dm−3 resulted in formation of different reaction product—octahedral cuprous oxide nanoparticles. Solutions were irradiated by means of electron beam, 60Co γ rays (dose rate 70 Gy.h−1) or by 400 W medium-pressure mercury lamp and were characterised by UV-Vis spectrophotometry, X-Ray Powder Diffraction, TEM and SEM. Pink to violet colour of colloidal copper solutions corresponded to measured copper surface plasmon band at circa 580 nm and has been found to be very sensitive to oxygen, which causes dissolution of particles. Therefore, the influence of purging by nitrogen gas prior to irradiation was thoroughly examined and has been found to only hinder, not alter irradiation effects. Moreover, the evolution of absorption spectrum of colloidal copper solution in contact with air has been measured, revealing interesting non-monotonous dependence on the air exposure time, probably caused by formation of protective oxide layer. Catalytic activity of prepared cuprous oxide has been measured by catalytic decomposition of hydrogen peroxide and has been found to be higher or comparable to commercial cuprous oxide.

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