Results 131 to 140 of about 2,824 (186)

Electrochemistry of chalcopyrite

Hydrometallurgy, 1996
Abstract The electrochemical response of a massive chalcopyrite electrode at two different temperatures, 25°C and 68°C, were compared. The electrolyte used in the experiments was an acidic medium (0.4 g ·1 −1 (NH 4 ) 2 SO 4 , 0.5 g ·1 −1 MgSO 4 · 7H 2 O, 0.2 g ·1 −1 K 2 HPO 4 at pH = 2) which is suitable for the growth of the microorganisms ...
Gomez, C, Figueroa, M, Munoz, J, Blazquez, ML, Ballester, A   +4 more
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Competitive bioleaching of pyrite and chalcopyrite

Hydrometallurgy, 2006
Abstract An experimental study was conducted to investigate the heap bioleaching of a copper-gold concentrate using the Geocoat™ technique. Small-scale columns were operated at selected temperatures using bacterial consortia suited to these temperatures. In all experiments secondary copper sulfides would leach more rapidly than pyrite.
Petersen, Jochen, Dixon, David G
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Phonons and electrons in chalcopyrite semiconductors

AIP Conference Proceedings, 2012
In recent years the phonons and the electron phonon interaction of binary tetrahedral semiconductors have been profusely investigated by ab initio techniques and compared with experimental results. Of particular interest have been binary compounds in which the cations contain semi-core d-electrons (CuCl, CuI, AgI) which display anomalies related to ...
Cardona, M., Kremer, R., Lauck, R., Romero, A., Munoz, A., Burger, A.   +5 more
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The Influence of pH and Ferrous Ions on Chalcopyrite Dissolution in Chemical Leaching Chalcopyrite

Advanced Materials Research, 2014
This paper studied the influence of pH, temperature and particle size on the chemical leaching of chalcopyrite. The results show that H+is not only responsible for the hydrolysis and precipitation of ferric ion as jarosite, but also related directly to chalcopyrite dissolution.
Xiao Lan Mo, Jian Kang Wen, Jing Bai, Bo Wei Chen, Biao Wu   +4 more
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Phonons in chalcopyrite compounds

AIP Conference Proceedings, 1999
The phonon dispersion curves along the [100] and [001] directions of CuInSe2 and AgGaSe2 have been measured by inelastic neutron scattering. They are analyzed with different rigid-ion models: Born-von Karman and valence force field models. The calculated dispersion curves are in good agreement with experiments.The phonon dispersion curves along the ...
P. Derollez, A. Laamyem, R. Fouret, B. Hennion, J. Gonzalez   +4 more
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Electrical properties of chalcopyrite

British Journal of Applied Physics, 1958
The conductivity σ and thermoelectric power of synthetic and natural specimens of chalcopyrite have been investigated in the temperature range -140 to 300° C. The Hall coefficient R of the natural specimens has also been measured in this region, but in the case of the synthetic specimens is too small to be detected.
B Donovan, G Reichenbaum
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On the Mössbauer effect of chalcopyrite

Il Nuovo Cimento B Series 10, 1967
We have examined the Mossbauer absorption spectrum of the57Fe 14.4 keV γ-rays from the CuFeS2 compound, at room temperature and liquid-nitrogen temperature. From the experimental values of the isomeric shift we infer that the chalcopyrite may be represented by the resonant configuration Cu+Fe+3(S−2)2 ↔ Cu−3 Fe−(S+2)2.
F. Aramu, T. Bressani, P. Manca
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Dynamics of the chalcopyrite lattice

Soviet Physics Journal, 1970
The symmetry properties of the normal modes of the chalcopyrite lattice are analyzed. The phonon spectra of chalcopyrite and sphalerite are compared. There is a discussion of the intensity of the IR absorption lines due to single-phonon processes. Selection rules are found for direct and indirect transitions. Carrier scattering by phonons is analyzed.
G. F. Karavaev, A. S. Poplavnoi, V. G. Tyuterev   +2 more
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Electronic properties of chalcopyrites

Journal of Physics and Chemistry of Solids, 1981
Abstract Using Phillips and Van Vechten theory [1–3], the values of the homopolar gap, ionic gap and Penn gap have been evaluated for thirty-one chalcopyrites. The values so derived have been found in accordance with the values obtained from the Penn model and the Phillips model. Using the above parameters the microhardness has been determined.
V.P. Gupta, V.K. Srivastava, P.N.L. Gupta   +2 more
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Hydrothermal synthesis of chalcopyrite

Economic Geology, 1966
Natural chalcopyrite was dissolved by NaCl solution at the warmer end of a reaction vessel and synthetic chalcopyrite was precipitated at the cooler end at temperatures of 400 degrees -500 degrees C. No transfer occurred with pure water.
W. M. Barnard, P. A. Christopher
openaire   +1 more source