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Showing 1 to 10 of 10 for “"Copper sulfides"”.
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Nonstoichiometry of chalcocite in water-xanthate systems
… mass-balanced, computer calculations for the copper-sulfur-water system involving different Cu/S ratios that pertain to chalcocite, djurleite, anilite and covellite. Calculations were completed for cases where oxidation of the sulfur proceeded to i) elemental sulfur, ii) thiosulfate, iii) …
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An investigation of the kinetics of thermophilic microbial ferrous iron oxidation in continuous culture
… thermophilic micro-organisms to bioleach primary copper sulfides and other minerals has led to the need to develop a fundamental understanding of the mechanistic process involved. Ferrous iron oxidation has been established as a key step in bioleaching and is understood to be achieved largely by …
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Linking Subsurface Paleofluid Flow Events to Tectonics and Basin Evolution using Geochronology: Examples from the Paradox Basin
… or clay-rich horizons. Metals such as copper, uranium, and vanadium are enriched in bleached sandstones following later stages of flow of oxidized fluids. Authigenic illite, copper sulfides, iron-, and manganese oxides are all fluid-rock interaction products that we utilized in this …
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Modeling chalcopyrite leaching kinetics
Chalcopyrite (CuFeS2) is the most abundant of the copper sulfides and also one of the most refractory for leaching. Several processing routes have been proposed to overcome drawbacks associated with environmental problems related to copper extraction from this mineral. Atmospheric leaching in …
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CREEP CORROSION OVER PLASTIC ENCAPSULATED MICROCIRCUIT PACKAGES WITH NOBLE METAL PRE-PLATED LEADFRAMES
… products were found to consist primarily of copper oxides, copper chlorides, and copper sulfides. No distinct differences in corrosion products composition was observed on the lead versus the mold compound surfaces. Conformal coating was identified as an effective mitigation strategy to …
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An Investigation of Ni and Cu Isotopic Fractionation in Basal Duluth Complex Cu-Ni-PGE Mineralization, Northeastern Minnesota
… with pronounced differences between primary copper sulfides and secondary copper phases in a variety of deposit types. Prior to this study, no δ60/58Ni or δ65/63Cu values have been measured in Duluth Complex rocks. The primary goal of this study is to measure Ni and Cu isotope values in a …
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Non-hydrolytic Sol-gel (NHSG) Synthesis of Transition Metal Sulfides and Theoretical Investigations
… is explored for the synthesis of binary metal sulfides.Sulfides, some of which are thermally unstable and highly oxygen sensitive, have applications in many areas, such as solar cells, catalysts, sensors, lubricants, semiconductors etc.<sup>2</sup> Despite the widespread use of sulfides, they …
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The stratigraphic and structural controls on copper-gold mineralization at Cassenha hill prospect, within the Archean to Paleoproterozoic Angolan shield, Congo craton, South Western Angola
The Cassenha Hill copper-gold prospect is situated in the Catabola area, Huambo Province, southwestern Angola. Geologically, the prospect is part of the Angolan Central Eburnean Zone (CEZ) and consists of Paleoproterozoic metasedimentary rock sequences which have been intruded by Eburnean …
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Gold and Base Metal Mineralization, Hydrothermal Alteration and Vein Paragenesis in the Spring Valley Deposit, Pershing County, Nevada
… less than 2%, and only trace amounts of copper sulfides--primarily chalcopyrite and tetrahedrite--are present. Ore mineralogy is much simpler than that of nearby deposits, with virtually no silver and volumetrically minor sulfide mineralization. Ore mineralogy, alteration mineralogy and …
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Heavy-metal-free colloidal nanocrystal heterostructures – synthetic chemistry and growth mechanisms
… Cu precursors in the synthesis of colloidal copper sulfide (Cu2-xS) nanocrystals affect the resulting shape and phase. Decreasing aspect ratio in 1D nanorods (eventually transitioning to 2D nanodisks) observed is consistent with the expected effects of decreasing Cu precursor reactivity. …