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Radiolysis of aqueous solutions of cobalt(II) and cobalt(III)

1:2 bis-carboxymethylaminodiethyl tetraacetate

Journal of Radioanalytical and Nuclear Chemistry
Authors: M. Hafez, H. Roushdy, and N. Hafez

Abstract  

Radiolysis of aqueous solution of di and trivalent cobalt with 1:2 (bis) carboxymethylaminodiethyltetraacetic acid (EGTA) was investigated, both in absence and in presence of oxygen. A radiolytic mechanism has been proposed. It has been shown that the degradation at the ligand of the chelate is due to OH only.

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synthesis and characterization of cobalt(0) nanoclusters stabilized by HPO 4 2− or poly(acrylic acid), PAA, as well as their use as catalysts in hydrogen generation from the hydrolysis of sodium borohydride (NaBH 4 ). The HPO 4 2− ion was preferred as an

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Abstract  

More than 99% of radioactive cobalt can be removed from water by precipitation as cobalt/III/ hydroxide. The process is continuous and uses either sodium hypochlorite or oxygen and calcium sulfite to oxidize the cobalt. Carbonate and phosphate interfere with cobalt removal, but the process has potential for other applications such as thallium removal and sewage treatment.

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Acta Ethnographica Hungarica
Authors: Anna Ridovics, Zoltán May, Bernadett Bajnóczi, and Mária Tóth

International Symposium on Archeometry , May 15–19, Mexico. 1 – 4 . G RATUZE , B. – S OULIER , I. – B LET , M. – V ALLAURI , L. 1996 : De l’origine du cobalt: du verre à la céramique . Revue d’Archéométrie 20 , 77 – 94 . G YURICA Anna 1992

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Natpakan Srisawad, Wasu Chaitree, Okorn Mekasuwandumrong, Artiwan Shotipruk, Bunjerd Jongsomjit, and Joongjai Panpranot

cobalt FTS catalysts are prepared by the incipient wetness impregnation of aqueous solutions of cobalt salts onto the porous oxide supports followed by thermal decomposition of cobalt salts via calcination in an oxidizing atmosphere and reduction in

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Introduction The last few decades have witnessed exponential growth in the applications of commercial electronics following discovery of certain very useful materials. A typical example is cobalt ferrite which has gained

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under high pressure. Therefore, Fe and Co are considered most adequate for commercial processes. Cobalt-based catalysts have been successfully used commercially because they show high activity and selectivity for heavy hydrocarbons. Other benefits of Co

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materials because of their various applications such as solid oxide fuel cell (SOFC) cathodes and dense ceramic membrane for oxygen separation [ 4 ]. Among the various oxides used, a layered group of cobalt-based perovskites with formula REEBaCo 2 O 5+d

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Abstract  

The sorption of cobalt on natural and modified clinoptiolites has been studied. It has been demonstrated that the higher sorption of cobalt on modified clinoptinolites than on natural ones is due to precipitation reactions. The precipitates formed on the sorbent have been investigated by infrared spectrometrical, microscopical, and X-ray analyses. The capacity values of the corresponding metal forms of clinoptilolite have been obtained with cobalt. Desactivation of radioactive solutions containing134Cs,137Cs204Tl and The sorption of cobalt on natural and modified clinoptiolites has been studied. It has been demonstrated that the higher sorption of cobalt on modified clinoptinolites than on natural ones is due to precipitation reactions. The precipitates formed on the sorbent have been investigated by infrared spectrometrical, microscopical, and X-ray analyses. The capacity values of the corresponding metal forms of clinoptilolite have been obtained with cobalt. Desactivation of radioactive solutions containing134Cs,137Cs,204Tl and60Co ions simultaneously on natural sorbents by precipitation reaction has been achieved.

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Abstract  

Cobalt—tin alloys electrocodeposited from a mildly alkaline sulfate bath were studied using119Sn absorption and57Co Emission Mössbauer Spectroscopy. The Results reveal that dissolved tin and cubic CoSn (not appearing in the phase diagram) are the components obtained from fresh plating solutions. Upon exhaustion, the formation of Co3Sn2 is favoured, with the eventual deposition of cobalt particles as a separated phase. A precipitate is formed during bath operation which is richer in Sn(II), contrasting to the mother solution which is richer in Sn(IV).

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