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Showing 1 to 20 of 65 for “"Talc"”.
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The Paragenesis of Synthetic Phyllosilicates on The Talc-Phlogopite Join
Made available in DSpace on 2014-12-14T07:10:55Z (GMT). No. of bitstreams: 1 8009209.pdf: 5670512 bytes, checksum: d414ddd5fb6a9fcb9a7a51e02c9753d6 (MD5) Previous issue date: 1979
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Determination of Surface Free Energies and Aspect Ratio of Talc
… to assess the surface chemistry of the mineral talc. The contact angles were performed on both flat and powdered samples and the results were used to determine the surface free energy components and parameters (SFEC) using the acid-base theory for solids, according to the van Oss-Chaudhury-Good …
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Surface Forces between Silica Surfaces in CnTACl Solutions and Surface Free Energy Characterization of Talc
… energy (γ<sub>s</sub>) and its components of talc samples. The results showed that the basal surfaces of talc are weakly basic while the edge surfaces are acidic. The effect of chemicals on the surface free energies of talc was systemically studied. The results showed that CMC (carboxymethyl …
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Surface properties of New York talc as a function of pH, polymer adsorption and electrolyte concentration
Talc is a common siliceous gangue mineral found in ore bodies beneficiated by flotation. Talc is a layered anisotropic mineral, with a mineral structure comprising of basal planes and edges. The basal planes of talc are considered completely neutral, while the edges of talc are thought to undergo a …
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Comparison study of Taurolidin, Talc, Tetracycline and Bleomycin Pleurodesis in the Rabbit Model : Analysis of the Taurolidin's effectiveness
… pleurodesis. Numerous sclerosing agents such as Talc, Tetracycline, Doxycycline and Bleomycin have been used to induce pleurodesis. These agents have some limits of these use. Therefore some have used Taurolindin (Taurolineⓡ) as chemical irritant which is inexpensive, nontoxic and easy to deal. …
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The influence of polymeric charge and structure, molecular weight and ionic conditions on depressant ability to reduce the natural floatability of talc
Talc is a naturally floatable gangue material common in South African platinum bearing (PGM) ore bodies. Long chain polysaccharide depressants are effective in depressing talc flotation and improving the grade of the concentrates of those ores with talc as a gangue constituent. This thesis …
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Surface Free Energy Characterization of Powders
… were conducted on both flat and powdered talc samples, and the results were used to determine the surface free energy components using Van Oss-Chaudhury-Good (OCG) equation. It was found that the surface hydrophobicity of talc increases with decreasing particle size. At the same time, both …
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The effect of polysaccharides and inorganic dispersants on the surface characteristics of talc and the effect on the flotation performance of a Merensky ore
… dispersant on the surface characteristics of talc and how this relates to the flotation performance of Merensky ore. The rationale in investigating the talc changes are due to its naturally flotable nature and the downstream problems that result from its reporting to the concentrate causing …
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Geochemical Investigations of Respirable Particulate Matter
… rates of a well-characterized sample of powdered talc were measured in solvents that mimic fluids found in the human lung. These studies showed that variation of solvent chemistry, including the addition of organic chelators and proteins at intercellular fluid concentrations, does not markedly …
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Investigating the use of sodium metasilicate to improve the flotation performance of altered PGE ores
… revealed large quantities of serpentine and talc present within the ore sample used in this study, which led to a poor flotation response, as indicated by batch flotation tests. Using sodium metasilicate improved the recoveries and grades at high dosages (>1000 g/t). A suite of techniques was …
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Investigation of the surface properties of gangue minerals in PGM bearing ores
… of naturally floatable gangue minerals such as talc. Although talc is present in small quantities it has a disproportionate effect on concentrate grade by enhancing froth stability and increasing the entrainment of other gangue minerals. However, there is an indication that some of the other …
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Selective Reduction of Laterite Ore
… by XRD in the original ore included chlorite, talc, hematite and quartz. Traces of iron silicate, Fe-Cr spinel and monoxide phase were observed by EDS. Nickel was detected in chlorite, talc, iron silicate and monoxide. At 600 °C, dehydroxylation of chlorite occurred. Chlorite was converted into …
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An investigation of the failure mechanisms of thermoplastic composites at various rates of strain and temperatures
… and polyamide resins with glass fibres and talc as fillers. These materials were provided by PLASTAMID (pty) ltd. The injection moulded specimens of polypropylene, polyamide 6-6, 30% talc filled polypropylene, 30% short glass fibre reinforced polypropylene and 30% short glass fibre …
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Investigating the use of sodium silicate to improve the flotation performance of Platreef and UG2 PGE ores
… gangue minerals; namely serpentine and talc. The presence of these minerals poses three major problems to valuable mineral recovery. Firstly, serpentine slimes may form a hydrophilic layer on the valuable mineral surface leading to a decrease in recovery. Secondly, serpentine and talc …
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Seed and vegetative propagation methods for the rare Florida native species Chionanthus pygmaeus (pygmy fringetree)
… cuttings were treated with either 1000 ppm IBA talc, 8000 ppm IBA talc, or inert talc. All cuttings were placed on a mist bench in a greenhouse for 9 weeks. Hardwood cuttings were supplemented with bottom heat at 24 °C. No treatments were successful in inducing adventitious root formation. I …
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The role and fate of fluid inclusions in natural and experimental deformation
… deformation (i.e. dislocation creep). Talc was used in experiments to add water to the sample (via dehydration at elevated temperature), and was fitted as a sleeve around the outer cylinder of samples or inserted as a cylinder into cored samples. Results from anneal experiments (chapter …
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Investigation of the effect of hydrocarbon spillages and their interaction with alteration minerals on the flotation of UG2 PGE ore
… alteration minerals (serpentine, chlorite and talc) from weathered or altered ores. The near-surface Two Rivers Platinum (TRP) UG2 ore is routinely exposed to hydrocarbon contamination when the underground ore is excavated and transported to surface, resulting in reduced PGE flotation …
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Investigating the relative adsorption of polymeric depressants on pure minerals
… 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 preferentially onto different …
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Experimental investigation of the fluid driven carbonation of serpentinites and spinel-peridotites: implications for the carbon and trace element cycle in the forearc region of the mantle wedge
… in the fluid, magnesite is formed with quartz, talc and antigorite at 1-2.5 GPa and 375-650 °C. Above antigorite stability, magnesite is stable with talc, talc+enstatite and enstatite±forsterite. Excess aluminium derived from the consumed serpentine or pyroxenes leads to the formation of …
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Experimental investigation of the fluid driven carbonation of serpentinites and spinel-peridotites: implications for the carbon and trace element cycle in the forearc region of the mantle wedge
… in the fluid, magnesite is formed with quartz, talc and antigorite at 1-2.5 GPa and 375-650 °C. Above antigorite stability, magnesite is stable with talc, talc+enstatite and enstatite±forsterite. Excess aluminium derived from the consumed serpentine or pyroxenes leads to the formation of …
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