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Yemul, O. S. "Novel polyarylene sulphides". Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 1998. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/3370.
Pełny tekst źródłaIgiehon, Uwagboe Osamede. "Carbothermic reduction of complex sulphides". Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/46358.
Pełny tekst źródłaBayerköhler, Frieder [Verfasser], i Philipp [Akademischer Betreuer] Kurz. "Iron-molybdenum sulphides as proton reduction catalysts". Freiburg : Universität, 2017. http://d-nb.info/1144148901/34.
Pełny tekst źródłaSmit, Timotheus Servaas. "Hydrodesulphurization of thiophenes using transition metal sulphides". Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/28084.
Pełny tekst źródłaO'Sullivan, Susan Nora. "The synthesis and application of chiral sulphides". Thesis, University of Cambridge, 1994. https://www.repository.cam.ac.uk/handle/1810/272788.
Pełny tekst źródłaCoimbatore, Dhandayuth Venkatesh. "Cerium chloride inhibition for high strength low alloy steel exposed to sulphide polluted seawater". University of Western Australia. School of Mechanical Engineering, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0134.
Pełny tekst źródłaMulligan, David John. "Reduction of sulphur dioxide over transition metal sulphides". Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61916.
Pełny tekst źródłaArterton, Bruce William. "Preparation related luminescent properties in II-VI sulphides". Thesis, Coventry University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386517.
Pełny tekst źródłaAtkins, Alison J. "Solid state studies of ternary oxides and sulphides". Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320791.
Pełny tekst źródłaMaynard, Jonathan. "The genesis of sulphides in the Shetland ophiolite". Thesis, Open University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358559.
Pełny tekst źródłaMasenya, Mamago Adolphina. "Computational modelling studies of precious mixed metals sulphides". Thesis, University of Limpopo, 2016. http://hdl.handle.net/10386/1725.
Pełny tekst źródłaThe stabilities of PtS to PdS and PdS to PtS were investigated using density functional theory within the generalized gradient approximation. Their structural, electronic and mechanical properties were determined to show their stability and the effect of pressure on different compositions. We found good correlation of calculations with available ex-perimental data. The lattice parameters were observed to fluctuate with increasing con-centration for both systems. Furthermore, heats of formation were calculated to deter-mine the relative structural stability of the systems. They predict that the most stable structure is Pd50S50 P42/mmc and Pt25Pd25S50 P42/mmc being the least stable. Pd12.5Pt37.5S50 P42/m is the most stable and Pd50S50 P42/m being the least stable struc-ture. The Pt37.5Pd12.5S50 P1 was said to be the most stable structure and Pd50S50 P1 be-ing the least stable. The phonon dispersion calculations show that Pt50S50 P42/mmc, Pd50S50 P42/mmc, Pd12.5Pt37.5S50 P42/m and Pt50S50 P1 (derived from P42/mmc) are me-chanically stable, consistent with calculated elastic constants. The Pt25Pd25S50 P42/mmc show soft modes, which are due to vibrations of Pt and Pd atoms in the x - y plane which suggests the instability of the structure, in agreement with C66 being negative, and consistent with heats of formation. The lattice parameters decreased steadily with increasing pressure. An anomaly was observed in Pt50S50 P1 (derived from P42/mmc), where the c lattice parameter was found to increase with increasing pressure. The elec-tronic density of states (DOS) were performed on all compositions. The DOS were sub-jected to pressure and it was generally noted that the band gap increases with increas-ing pressure. It was observed that the smaller the band gap, the more stable the struc-ture. Furthermore, phonon dispersions under pressure show that compounds with the P42/mmc and P1 (from P42/mmc) symmetries display the mixing of lower and upper en-ergy bands at pressures above 30 GPa.
National Research Foundation
Gauld, Chris M. B. "Characterisation of sulphides from the INCO WD-16 Ni-Cu sulphide deposit, Wisner Township, District of Sudbury, Ontario, Canada". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0019/MQ46482.pdf.
Pełny tekst źródłaHarrison, Mark Robert. "One-dimensional, mixed-metal sulphides – structural and physical properties". Thesis, University of Hull, 2011. http://hydra.hull.ac.uk/resources/hull:5281.
Pełny tekst źródłaGreen, Pamela Rose. "The synthesis and structure of ternary transition metal sulphides". Thesis, University of Nottingham, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284056.
Pełny tekst źródłaWhittles, T. J. "Electronic characterisation of earth-abundant sulphides for solar photovoltaics". Thesis, University of Liverpool, 2017. http://livrepository.liverpool.ac.uk/3010978/.
Pełny tekst źródłaDavid, Lorraine. "MBE growth and characterisation of metastable transition metal sulphides". Thesis, Heriot-Watt University, 2006. http://hdl.handle.net/10399/197.
Pełny tekst źródłaOlsen, Sarah. "Synthesis of Copper Sulphides: A Green Chemistry Microwave Approach". Thesis, KTH, Tillämpad fysik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-279452.
Pełny tekst źródłaCondon, Brian D. "Stereoselective bond formation via lithiation of asymmetric acyclic sulfides". Diss., Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/29911.
Pełny tekst źródłaHannaby, M. P. "Phenylthio-controlled migrations around rings". Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355872.
Pełny tekst źródłaElwell, S. "A study of europium compounds in unusual oxidation states by Mossbauer spectroscopy and other techniques". Thesis, University of Kent, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235331.
Pełny tekst źródłaThomson, G. F. "Palaeomagnetic and aeromagnetic studies of some sulphide deposits". Thesis, University of Newcastle Upon Tyne, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383983.
Pełny tekst źródłaKemp, Anthony John. "The geochemistry of metalliferous concretions and their associated permo-triassic sediments from Budleigh Salterton, Devon". Thesis, University of Bristol, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337174.
Pełny tekst źródłaMcKie, Marion Catherine. "The chemistry of 1,3,4-oxathiazol-2-ones and related systems". Thesis, University of Edinburgh, 1988. http://hdl.handle.net/1842/12633.
Pełny tekst źródłaEngin, Tahir. "Structural, magnetic and electron transport properties of mixed metal sulphides". Thesis, Heriot-Watt University, 2008. http://hdl.handle.net/10399/2059.
Pełny tekst źródłaWass, S. A. "Some reactions of iron and molybdenum sulphides and related compounds". Thesis, University of Reading, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370130.
Pełny tekst źródłaAuëner, Christian Carl. "The synthesis and characterisation of novel quasi one-dimensional sulphides". Thesis, University of Liverpool, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.414855.
Pełny tekst źródłaMueller, Moritz. "Biotic and abiotic alteration of hydrothermal sulphides at the seafloor". Thesis, University of Southampton, 2009. https://eprints.soton.ac.uk/69029/.
Pełny tekst źródłaSwartbooi, Ashton Mark. "Precipitation of nickel and cobalt sulphides using different reactor configurations". Master's thesis, University of Cape Town, 2005. http://hdl.handle.net/11427/6696.
Pełny tekst źródłaQuezada, Reyes Víctor Alejandro. "Pretreatment to the leaching of copper sulphides minerals in oxidizing media". Doctoral thesis, Universitat de Barcelona, 2021. http://hdl.handle.net/10803/670663.
Pełny tekst źródłaCopper production in Chile is developed by hydrometallurgical and concentration; copper concentrates are traditionally treated by the pyrometallurgical route. According to Cochilco, copper produced in 2019 by hydrometallurgical process represent a 27.3% of Chilean total copper production. However, this contribution is estimated to decrease to 11.6% by 2029, due to the depletion of copper oxides and the appearance of copper sulphides, mainly chalcopyrite, being this mineral refractory to conventional leaching conditions. An alternative to improve leaching efficiency is pretreatment prior to leaching, especially the effect of curing time. This variable can increases the kinetics of copper extraction, especially in sulphides ores, however, there is limited research about it. Studies on pretreatment evaluate the effect on leaching efficiency but not previous leaching. Furthermore, the reactions that govern this phenomenon have not been clearly identified. Therefore, the objective of this thesis is the evaluation of the effect of acid curing on the copper extraction from sulphides minerals in oxidizing media and in presence of chloride. A pure sample of chalcopyrite, chalcocite and a mine ore were used. Tests evaluating the effect of curing time, KNO3, NaCl and H2SO4 concentration have been carried out. The chalcopyrite sample effect was evaluated by ANOVA. The product generated in the pretreatment (agglomerates) has been characterized using different characterization techniques, such as: X-Ray diffraction, Scanning Electron Microscopy and Reflection Optical Microscopy. Furthermore, the effect of pretreatment has been evaluated on the leaching efficiency at different temperatures, leaching residues have also been characterized. In the pretreatment of the chalcopyrite sample and mine ore, under the conditions of 15 kg/t of H2SO4, 25 kg/t of NaCl and 15 days of curing time, the following products were identified: CuSO4, NaFe3(SO4)2(OH)6, Cu2Cl(OH) and S0. Regarding the chalcocite sample, under the conditions of with 30 kg/t of H2SO4, 40 kg/t of NaCl and 7 days of curing time, the following products were identified: Cu1.75S, Cu(OH)Cl, Na2SO4 and CuSO4. Finally, copper sulphides ore pretreatment improved leaching efficiency, between 4 and 6%, reaching a copper dissolution of 94% from chalcopyrite at 90 °C, strengthening the hydrometallurgy as an alternative treatment for copper sulphides ores.
Legrand, Daniel L. "Surface studies of nickel and iron sulphides with implications for flotation". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ31158.pdf.
Pełny tekst źródład'Arbeloff-Wilson, Sarah. "Reactions of the phosphaalkyne, PCBu't with metal sulphides, selenides and tellurides". Thesis, University of Sussex, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324201.
Pełny tekst źródłaAdegoke, Idowu Abiodun. "Experimental studies on hydrothermal mineral replacement of bornite by copper sulphides". Thesis, Adegoke, Idowu Abiodun (2021) Experimental studies on hydrothermal mineral replacement of bornite by copper sulphides. PhD thesis, Murdoch University, 2021. https://researchrepository.murdoch.edu.au/id/eprint/60897/.
Pełny tekst źródłaDeveci, Haci. "Bacterial leaching of complex zinc/lead sulphides using mesophilic and thermophilic bacteria". Thesis, University of Exeter, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341175.
Pełny tekst źródłaKeith, Manuel [Verfasser], i Karsten [Akademischer Betreuer] Haase. "From active submarine vent systems to fossil volcanic-hosted massive sulphide deposits: an in-situ analytical study of hydrothermal sulphides / Manuel Keith. Gutachter: Karsten Haase". Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2015. http://d-nb.info/1080362703/34.
Pełny tekst źródłaPoole, Mark Charles. "Synthetic and spectroscopic studies of organic sulphides, sulphoxides, sulphones, and their metal complexes". Thesis, University of Exeter, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332281.
Pełny tekst źródłaMoug, Richard T. "II/VI metastable sulphides : fundamental studies of MBE growth, characterization and nanostructure formation". Thesis, Heriot-Watt University, 2009. http://hdl.handle.net/10399/2279.
Pełny tekst źródłaSzkoda, Iwona. "Phase relations, structural studies and physical properties of mixed metal oxides and sulphides". Thesis, Heriot-Watt University, 2008. http://hdl.handle.net/10399/2212.
Pełny tekst źródłaGuelou, G. P. L. "On the structural and physical properties of Earth-abundant sulphides for thermoelectric applications". Thesis, University of Reading, 2016. http://centaur.reading.ac.uk/68420/.
Pełny tekst źródłaAbedelrasoul, Abuelgasim Abbaker. "Studies on the chemistry of some sulphides and of some sulphur-containing heterocyclic compounds". Thesis, University of Hull, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333763.
Pełny tekst źródłaMcMordie, Robert Austin Simms. "Synthetic, mechanistic and stereochemical studies of the primary metabolites of sulphides and cyclic hydrocarbons". Thesis, Queen's University Belfast, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335559.
Pełny tekst źródłaJean, R. N. Maïtena. "Étude de la matte sulfo-oxydante de la mangrove de Guadeloupe : caractérisation des micro-organismes principaux des familles Beggiatoaceae et Oscillatoriaceae". Thesis, Antilles-Guyane, 2013. http://www.theses.fr/2013AGUY0614/document.
Pełny tekst źródłaProcaryotic mats are ecological niches, occuring in many ecosystems. Those structures are little studied in marine mangrove sediment and have never been described in West Indies. The purpose ofthis thesis is to characterize the interactions between the mat and the environment, and between the different filamentous micro-organisms living into the mat. In a first place, we characterized the mainly micro-organisrns of the mat by sequencing 16S rDNA. We confirmed these sequences by molecular hybridization (FISH) with specific probes designed from sequences obtained. Thus, it was possible to describe two new Beggiatoaceae strains, whose structure has been studied by electronic microscopy. Furthemore, we used potentiometric captors in situ and in laboratory, by creating a mesocosm, in order to define the chemical environment where involved these bacteria. These experiences proved that the Beggiatoaceae of the mat oxidized the sulfur taking the oxygen from the medium, while the microscopic analysis coupled with EDX showed intracellular sulfur granules into the bacteria. The study of the filamentous cyanobacteria of the mat highlighted four new cyanobacteria strains, all studied by electronic rmcroscopy. Two of them belongs to Planktothrlcoides genus and showed positive toxicity on Artemia salina. The others species are close to Oscillatorla spongeliae, a sponge symbiont, nevertheless, one ofthem showed an intemal morphology close to Tychonema. The analysis of the different results adduces sorne knowledge about mangrove microbial communities. Furthermore, this study can be used as an interesting base to study the micro-organisms contribution in functioning mangrove ecosystem
Dasgupta, Jhinuk. "Investigation on some 2-Alkylamido 6-chloro/Nitro-4H-1, 3, 2-Benjodi-oxaphosphorin-2 - Sulphides having pesticidal activities". Thesis, University of North Bengal, 1988. http://hdl.handle.net/123456789/1130.
Pełny tekst źródłaRumball, John Alfred. "The interaction of partially weathered sulphides in the Mt McRae shale formation with ammonium nitrate". Thesis, Rumball, John Alfred (1991) The interaction of partially weathered sulphides in the Mt McRae shale formation with ammonium nitrate. PhD thesis, Murdoch University, 1991. https://researchrepository.murdoch.edu.au/id/eprint/51662/.
Pełny tekst źródłaWengorsch, Tobias. "Experimental Alteration in Composite Mineral Systems: Mg-silicates, Fe-Ni-sulphides and Fe-Ti-oxides". Thesis, Curtin University, 2019. http://hdl.handle.net/20.500.11937/78546.
Pełny tekst źródłaMadureira, Danielle Jannuzzi. "Analise da expressão de genes que codificam proteinas transportadoras em Acidithiobacillus ferrooxidans e Acidithiobacillus thioxidans na presença de sulfetos metalicos". [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/316929.
Pełny tekst źródłaDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Acidithiobacillus ferrooxidans e Acidithiobacillus thiooxidans são espécies bacterianas acidofilicas, quimiolitotróficas e mesofilicas, encontradas em ambientes de biolixiviação. A. ferrooxidans utiliza íons ferrosos e compostos que contém enxofte como doadores de elétrons enquanto que A. thiooxidans utiliza apenas enxofte e compostos contendo enxofte. Ambas as espécies utilizam principalmente o oxigênio como receptor final de elétrons, contudo, podem também crescer em ambientes de anaerobiose. A. thiooxidans possui maior resistência ao pH podendo ser encontrada em ambientes com pH variando de 0,5 a 5,0, enquanto que A.ferrooxidans é encontrada em pHs que variam de 1,0 a 2,5. Devido a essas características e devido a capacidade dessas bactérias de solubilizar metais, A. ferrooxidans e A. thiooxidans vem sendo utilizadas em experimentos de biolixiviação. Este processo é utilizado na indústria para recuperação de cobre devido às vantagens oferecidas. Entretanto, pouco se sabe sobre a resposta gênica destas bactériaS a presença de sulfetos metálicos e dos metais pesados em solução proveniente do processo de oxidação. Na primeira parte deste trabalho foi analisada a resposta gênica da estirpe de A. ferrooxidans LR na presença e na ausência de covelita (CuS) por 24 horas através da técnica de RAP-PCR (Random Arbitrarily Primed Polymerase Chain Reaction). Foram obtidos 19 cDNAs com expressão diferencial, dos quais 12 foram confirmados como sendo diferencialmente expressos. Dentre estes, foram isolados sete genes que codificam: proteínas de transporte (AFE 0123, AFE ,0989, AFE 0990, AFE 0580, AFE 0671, AFE 2248 e AFE 1149), a proteína diguanilato ciclase, uma proteína de membrana, uma metiltnmsferase e uma ATPase, todas induzidas na presença da covelita. Apenas o gene infC, que codifica um fator de iniciação de tradução tipo 3, teve sua expressão reprimida na presença de covelita. Como sete dos genes diferencialmente expressos pertenciam à classe de transportadores, foram investigadas às modificações químicas presentes no meio de cultura após 24 horas. Análises de absorção atômica mostraram que a quantidade de' co1?rê em solução inicialmente zero passava para aproximadamente 1,13 g/L e medidas de pH mostraram que após este período de tempo houve mudanças de 1,8 para 4,0. Pode-se sugerir que essas alterações químicas sejam responsáveis, pelo menos em parte, pela indução dos genes que codificam proteínas de transporte. Uma análise in silico da interação entre proteínas (PPI) relacionadas com transporte, cujos genes foram diferencialmente expressos na presença de covelita e de proteínas pertencentes à mesma categoria funcional, codificadas por genes que estavam fisicamente localizados nas proximidades dos genes diferencialmente expressos, mostraram que os genes de transporte podem estar envolvidos em diferentes etapas da resposta bacteriana à presença de covelita. A segunda parte deste trabalho teve como objetivo estudar a expressão diferencial, por PCR em tempo real, de duas proteínas do tipo ABC (AFE 0123 e AFE 0125) e uma proteína do tipo RND (AFE 0993) na estirpe de A. thiooxidans FGOl na presença de calcopirita (CuFeS2), covelita e pirita (FeS2) por 24 horas. Para tal, a estirpe foi crescida na presença de enxofte e depois mantida na presença dos sulfetos metálicos por 24 horas. A expressão dos três genes foi induzida na presença de covelita e inalterada na presença de calcopirita. Na presença de pirita, a expressão de dois genes foi reprimida e do gene AFE 0993, permaneceu inalterada. Estes resultados podem ser explicados, pelo menos em parte, pelas quantidades de cobre encontradas em solução na presença de covelita (l g/L) e na presença de calcopirita (0,07 g/L). Na presença de covelita e calcopirita a medida de pH também softeu aumento de 1,8 para 4,0 e 2,5, respectivamente. Para investigar se a alteração de pH ou a presença de íons de cobre eram os responsáveis pela indução da expressão desses genes, a bactéria foi mantida na presença de sulfato de cobre (16 mM) e pH 4,0 por 24 horas. Os resultados mostraram que a presença de cobre em solução induz a expressão destes genes, enquanto que a alteração do pH não
Abstract: Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans are acidophilic, chemolitotrophic and mesophilic bacteria found in bioleaching environments. A. ferrooxidans uses ferrous iron and sulphur compounds as an e1ectron donor and A. thiooxidans uses on1y sulphur and sulphur compounds. Both species are aerobic using oxygen as final e1ectron acceptor. However, these bacteria are also able to grow in anaerobic environments. A. thiooxidans is able to survive in pHs ranging from 0.5 to 5.0 while A. ferrooxidans grows in pHs from 1.0 to 2.5. Due to these characteristics and the ability of these bacteria to solubilize metal sulphides, A. ferrooxidans and A. thiooxidans are used in bioleaching. This process has several advantages over the traditional methods and has been used with success in industrial operations to recover main1y copper. However, little is known about the genetic response of these bacteria to the presence of metal sulphides and heavy metal in solution. Therefore, in the first part of this study the A. ferrooxidans LR 'response to covellite was investigated. This bacterium was maintained in contact with covellite for 24 hours and the differentially expressed cDNAs were identified by RAP-PCR (Random Arbitrarily Primed Polymerase Chain Reaction) technique. Nineteen cDNAs showed a differential expression and twe1ve had their differential expression confirmed by real time PCR. Among these cDNAs, seven codified for transporter proteins (AFE 0123, AFE 0989, AFE 0990, AFE 0580, AFE 0671, AFE 2248 and AFE 1149), one codified for a putative diguanylate cyc1ase, one for a membrane. protein, one for a methyltransferase and one for an A TPase. With the exception of infC whose expression was down regulated, all the oDNAs had their expression up regulated in the presence of covellite. Since most of the differentially expressed genes are involved in transport, chemical modifications on the culture medium after 24 hours were investigated. The atomic absorption analysis showed that the copper amount in solution was 1.13 g/L and pH changed from 1.8 to 4.0 suggesting that these changes are responsible, at least in part, for the induction,"?f1he expression of transport gene. An in si/ico ana1ysis of protein-protein interaction (PPI) between the transport proteins codified by the genes differentially expressed in the presence of covellite and those codified by genes that were physically located around the differentially expressed ones showed that these transport proteins could be involved in different steps of the bacterial response to covellite. The goal of the second part of this study was to analyse the differential expression, by real time PCR, of two ABC proteins (AFE 0123 andAFE 0125) and one RND protein (AFE 0993) inA. thiooxidans FGOl in the presence of chalcopyrite, covellite and pyrite for 24 hours. This strain was maintained in contact with the metal sulphides for 24 hours. The expression ofthe three genes was up regulated in the presence of covellite and unchanged in the presence of chalcopyrite. In the presence of pyrite two genes hOO their expression down regulated and in one (AFE 0993) the expression was unchanged. These results can be explained, at least in part, by the quantities of copper found in solution in covellite (1 g/L) and in chalcopyrite (0.07 g/L). In the presence of covellite and chalcopyrite the pH changed from l'.8 to 4.0 and 2.5, respectively. To investigate if the changes in pH or the presence of copper ions in solution were responsible for the induction of the gene expressions, the bacteria were maintained in the presence of copper sulphate (16 mM) and pH 4.0 for 24 hours. The results showed that the presence of copper in solution was the responsible for the up regulation ofthese genes
Mestrado
Biologia Celular
Mestre em Genética e Biologia Molecular
Almeida, Carolina Michelin de. "Gênese dos corpos de sulfeto maciço hidrotermal e platinóides associados no depósito de Fortaleza de Minas (MG) /". Rio Claro : [s.n.], 2003. http://hdl.handle.net/11449/92912.
Pełny tekst źródłaBanca: Antenor Zanardo
Banca: João Batista Moreschi
Resumo: A mineralização sulfetada de Ni-Cu-Co (PGE), associado a rochas komatiíticas, da Jazida de Fortaleza de Minas, no sudoeste do Estado de Minas Gerais é tido como de origem magmática, porém processos pós-magmáticos modificaram substancialmente a distribuição original, estrutura, textura, mineralogia e química dos minérios. Estão presentes três importantes tipos de minérios sulfetados mobilizados: brecha, formação ferrífera bandada (BIF) e minério maciço hidrotermal. O último, é o objeto de estudo desta pesquisa. O minério maciço hidrotermal está associado a zonas de falhas transversais tardias, de direção NE-SW e N-S que cortam as rochas hospedeiras, e são perpendiculares a principal zona de cisalhamento que contém o principal corpo de minério. O minério maciço hidrotermal é formado por uma matriz oxi-sulfetada, constituída por pirrotita, pentlandita, calcopirita, pirita, violarita e magnetita, contendo minerais da série cobaltita-gersdorffita, minerais do grupo da platina, minerais da série linneita-polidymita, siegenita, além de carbonatos e quartzo. Os minerais do grupo da platina ocorrem disseminados por todo minério, associados a fases silicáticas hidratadas, inclusos em grãos de magnetita e minerais da série cobaltita-gersdorffita, no contato entre o minério e as rochas encaixantes. Próximo ao contato, são observados típicas feições de alteração hidrotermal do tipo talco-carbonato-clorita-sulfeto. Ao final do evento tectono-metamórfico, durante o Neo Proterozóico, que atuou na área em condições de baixa a alta temperatura (fácies xisto verde), foram produzidas diversas soluções hidrotermais que afetaram as rochas encaixantes nas proximidades do corpo de minério, bem como do próprio minério, originando um novo tipo de minério, aqui designado como minério maciço hidrotermal.
Abstract: The komatiite-associated Ni-Cu-Co (PGE) sulphide mineralization at Fortaleza de Minas, southwestern of Minas Gerais state is believed to have a magmatic origin, but a number of post-magmatic processes significantly modified the original distribution, structure, texture, mineralogy and chemistry of the ores. Three important types of mobilized sulphide are present: breccia, banded iron formation (BIF) and hydrothermal massive ore. The last is the object of study of this research. The hydrothermal massive ore are associated to the late transversal fault zones, of N-S and NE-SW direction that cut host rocks, and are perpendicular to the principal shear zone that comprise the main ore body. The hydrothermal massive ore is formed by a massive oxi-sulphated matrix, consisted of pyrrhotite, pentlandite, chalcopyrite, pyrite, violarite and magnetite, comprising cobaltite-gersdorffite minerals series, platinum-group minerals, linnaete-polydymite minerals series, siegenite, besides carbonates and quartz. The platinum-group minerals occur disseminated over the entire ore, associated to hydrated siliceous phases, and enclosed in magnetite grains and cobaltite-gersdorffite mineral series, in the contact between the ore and enclosing rocks. Next to this contact, are observed typical hydrothermal alteration features as talc-carbonate-chlorite-sulphide. In the end of the tectonic-metamorphic event, during the Neo Proterozoic, that actuated in the area in conditions of low to medium temperatures (greenschist facies), were produced a number of hydrothermal solutions that affected enclosing rocks next to the ore body as well as the proper ore, generating a new type of ore, here designated as hydrothermal massive ore.
Mestre
MacRobbie, Paul Alexander Carleton University Dissertation Geology. "Stratigraphy, structure and volcanogenic sulphides, in Sicker group volcanic rocks on Mt. Sicker, Vancouver Island, B.C". Ottawa, 1988.
Znajdź pełny tekst źródłaHagerfors, Erika. "Formation of Sulphides in the Canadian High Arctic Large Igneous Province; Testing the Influence of Sedimentary Rocks". Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-357415.
Pełny tekst źródłaStora magmatiska provinser (på engelska Large Igneous Provinces, LIPs) är vulkaniska event då enorma mängder magma avsätts över en väldigt stor yta under ett, i ett geologiskt perspektiv, kort tidsspann. Dessa stora vulkaniska utbrott har väckt stort intresse då de är samtida med flera av de största massutdöendena i jordens historia, men också för att en viss typ av sulfidmalm rik på nickel, koppar och platinametaller (Ni-Cu-PGE malmer) ofta förekommer i provinsernas magmagångar och magmakammare. En viktig faktor som till stor del avgör en magmatisk provins påverkan på klimatet och potentiella malmförekomster är inkorporering av sedimentära bergarter till magman som, när de hettas upp, kan frigöra gaser rika på svavel och kol. I Kanadas arktiska öar trängde magma tillhörande den högarktiska magmatiska provinsen (HALIP) in i svart skiffer, karbonater och evaporiter, som är sedimentära bergarter rika på flyktiga ämnen. Denna magmatiska provins erbjuder därför stora möjligheter till att studera interaktionen mellan magma och sedimentära bergarter. Syftet med denna studie är att testa om inkorporering av sedimentärt svavel kan främja bildandet av sulfidsmälta i magma och därigenom bidra till bildandet av sulfidmalmer. Detta görs genom att analysera svavelisotoper i sulfidmineral i prover från en magmagång, som trängde in i en skifferformation, tillhörande den högarktiska magmatiska provinsen i norra Kanada. Genom att analysera svavelisotopkvoten (δ34S) i sulfidmineral kan man få information om huruvida svavlet i mineralen är av sedimentärt ursprung (där skiffer generellt har negativa δ34S värden) eller om svavlet har δ34S värden liknande de från manteln (som har δ34S värden runt 0‰), vilket i så fall skulle innebära att magman inte har inkorporerat sedimentärt svavel. Genom att använda masspektrometri av typen SIMS analyseras totalt 14 sulfidmineralkorn (n = 246 individuella SIMS punkter) för deras svavelisotopkvoter. Resultatet av studien visar att alla analyserade sulfidmineral har mycket negativa δ34S värden mellan -19.5 och -5.7‰ (med ett δ34S medelvärde på -8.2 ± 0.83‰, två standardavvikelser). Genom att jämföra våra δ34S värden med δ34S och δ18O värden för andra prover från både magmagången och den omgivande skiffern kunde vi se att δ34S värdena för sulfidmineralen i de yttre delarna av magmagången har liknande negativa värden som den omgivande skiffern, och att δ34S värdena för skiffern närmast magmagången är mer positiva. Detta tyder på att sedimentärt svavel i kontakten mellan magmagången och skiffern har blivit inkorporerat i magman från den omgivande skiffern. Våra resultat tyder därför på att sulfidmineralen i våra prover från magmagången bildades genom assimilering av svavel från den omgivande skiffern. Detta innebär i sin tur att den kanadensiska högarktiska magma provinsen potentiellt kan vara en källa för sulfidmalm, även om ytterligare studier behövs. Dessutom visar våra resultat att inkorporering av sedimentärt svavel förmodligen ökade de vulkaniska gaserna i magman, vilket kan ha bidragit till klimatförändringar relaterade till den vulkaniska aktiviteten av den högarktiska magmatiska provinsen.
Lindeberg, Tomas. "Indium Analysis and Small-scale Distribution in Sulphides from the Lindbom Prospect, Långban Area, Western Bergslagen Ore Province". Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-196479.
Pełny tekst źródłaMissack, Evon A. "Mineralogy and phase relations of the massive sulphides and metalliferous sediments of the Axial Rift Valley, Red Sea /". Heidelberg : [Ruprecht-Karls-Universität], 1988. http://catalogue.bnf.fr/ark:/12148/cb37429905t.
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