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Showing 1 to 20 of 64 for “"mineral surface"”.
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Mineral-Surface Chemistry of Hydroxyapatite and Urea-Rich Solutions
… of phosphorus, which is primarily found in solid mineral sources. Phosphorus in biological systems is significant through its involvement in metabolic functions (<em>e.g.,</em> Coenzyme A), cell structure (<em>i.e., </em>phospholipid membranes), and genetic storage/transfer (<em>i.e.,</em> …
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Nuclear magnetic resonance investigation of mineral surface reactions involving inner-sphere and outer-sphere complexes
… behavior of anions and cations adsorbed onto mineral surfaces, using $\sp{31}$P and $\sp{133}$Cs magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy. Phosphate and Cs are good examples of inner-sphere and outer-sphere complexes, respectively, and this study shows that NMR …
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Mineral Surface Catalyzed Polymerization Of Estrogen And Microbial Deactivation By Fe3+-Saturated Montmorillonite: A Potentially Low Cost Material For Water Decontamination
… swelling-shrinking property and large specific surface area, monmtorillonite is chosen as a carrier and modified with Fe3+ saturation for estrogen decontamination. 17β-Estradiol (βE2) has highest estrogenic activity among estrogens and is selected as representative compound. Rapid βE2 …
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The synergistic interaction between dithiophosphate and frothers at the air-water and mineral-water interface
… roles. Collectors selectively hydrophobized the mineral surface and frothers adsorb onto bubbles inhibiting bubble coalescence and stabilizing the froth. Interactions between these molecules have been previously reported in literature (Leja & Schulman, 1954; Lekki & Laskowski, 1971; Dai, Bradshaw …
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Mineral-Microbe Interactions Probed in Force, Energy, and Distance Nanospace
… (nanometers) between living bacteria and mineral surfaces, in aqueous solution. Native cells were linked to a force-sensing probe, which was used in a force microscope to measure attractive and repulsive forces as a mineral surface approached, made contact with, and subsequently withdrew …
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Water quality effects on the bubble-particle attachment of sulfide minerals
… Zeta potential measurements showed that the surface charge of the particles became less negative as the ionic strength of the water increased; this indicates the adsorption of cations on the particle surface. Furthermore, at the pH these tests were conducted (pH 6.5 to 7), the surface …
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Investigating the Influence of the Electrochemical Environment on the Flotation of a Mixed Sulphide Mineral System of Bornite and Chalcocite
… critical front-end process used to remove gangue minerals and concentrate the copper minerals. However, flotation is an electrochemically intense process with multiple redox reactions taking place simultaneously. The interdependency of these processes makes it extremely difficult to isolate the …
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Ammonia leaching as a pre-treatment for the processing of oxidised PGM ores
The exploitation of near-surface deposits has resulted in the need to adjust current conventional mineral processing technologies for the treatment of low grade oxidised PGM ores. The exposure of the ore to the atmosphere leads to the formation of an oxidation layer (consisting of base metal …
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Interfacial and long-range electron transfer at the mineral-microbe interface
… mediated by proteins in direct contact with mineral surfaces, monolayers of purified decaheme cytochromes from the metal-reducing bacterium Shewanella oneidensis were prepared on Au(111) surfaces. Recombinant tetracysteine sequences were added to two outermembrane decaheme cytochromes (OmcA …
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Enhancing the recoveries and grades of Cobalt from Nchanga and Konkola Ores of KCM
… and Cobaltiferous pyrite ((Co,Fe),S2). These minerals are found in association with copper minerals such as chalcopyrite (CuFeSz), Bomite (CusFeS4) and Chalcocite (CujS). However, the recoveries of cobalt minerals in both Concentrators are low (45-50%TCo). In this work, a combination of the …
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Enhancing the recoveries and grades of Cobalt from Nchanga and Konkola Ores of KCM
… and Cobaltiferous pyrite ((Co,Fe),S2). These minerals are found in association with copper minerals such as chalcopyrite (CuFeSz), Bomite (CusFeS4) and Chalcocite (CujS). However, the recoveries of cobalt minerals in both Concentrators are low (45-50%TCo). In this work, a combination of the …
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Investigating the relative adsorption of polymeric depressants on pure minerals
… adsorption of polymeric depressants on pure minerals. The minerals used were talc, pyroxene, plagioclase, chromite and chalcopyrite and the depressants used were guar gum and carboxymethyl cellulose (CMC). It was hypothesised at the beginning of this study that polymeric depressants adsorb …
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The thermochemical behaviour of thiol collectors and collector mixtures with sulphide minerals
… the base metal sulphide (BMS) and platinum group mineral (PGM) flotation industry. The behaviour of thiol collectors and collector mixtures with sulphide mineral surfaces has been extensively studied using different techniques such as XPS, ToF-SIMS, UV-VIS, etc. However, most of these techniques …
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Exploring Siderophore-Mineral Interaction Using Force Microscopy and Computational Chemistry
… between the siderophore azotobactin and the minerals goethite (FeOOH) and diaspore (AlOOH) in solution using force microscopy. Azotobactin was covalently linked to a hydrazide terminated atomic force microscope tip using a standard protein coupling technique. Upon contact with each mineral …
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Control of Surface Chemistry of Gold, Pyrite and Pyrrhotite
… dixanthogen is the only species that renders the surface hydrophobic. Chemisorbed xanthate is observed on the gold surface but is hydrophilic. The synthetic polymers may adsorb on pyrite and pyrrhotite possibly through the hydrophobic interaction between the hydrophobic moiety of the polymer and …
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The role of nitrogen on the flotation performance of a complex sulphide ore
… of the complex sulphide ore, as measured by mineral recoveries and grades of the major sulphide elements, copper, nickel and iron. These represent the major sulphides present in the ore; chalcopyrite (Cu), pentlandite (Ni) and pyrrhotite (Fe, as an approximate representative since Fe occurs …
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An investigation into the relationship between electrochemical properties and flotation of sulphide minerals
There is a growing importance in the mineral processing industry to find ways which are economic and effective in improving the recovery of minerals in the flotation process. The focus of this study was on the recovery by flotation of minerals found in the Merensky reef, which is one of the major …
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An investigation into the effects of pulp chemistry under wet and dry grinding on the flotation response of pyrite
… to have a fundamental understanding of minerals processing operations in order to improve the recoveries of valuable metals on an industrial scale. It has been acknowledged that the chemical conditions during grinding as well as pulp chemistry have a significant influence on the recovery …
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An investigation into the flotation response of sperrylite (PtAs2) by comparative evaluation of crystal structure and bonding atoms
… in the world. One of the major platinum group mineral (PGM) components in this ore is sperrylite (PtAs2), which has been found to be slow floating compared to the other PGMs and often reports to the tailings stream. Sperrylite comprises about ~21% of the platinum groups minerals (PGMs) in the …
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Adsorption Properties of Roxarsone and Arsenate on Goethite and Kaolinite
… and kaolinite in order to determine what role mineral surfaces play in controlling the mobility of roxarsone in watersheds where poultry litter is applied. Adsorption edge experiments for goethite and kaolinite showed a dependence on pH for both As(V) and roxarsone. This pattern can be …
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