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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The separation of the polar constituents of petroleum

Robson, William January 2018 (has links)
Identification of the heteroatom (nitrogen, sulphur, and oxygen; NSO)-containing compounds of petroleum is of key importance when considering industrial and environmental issues associated with crude oil production. The inherent molecular complexity of petroleum is such that detailed compositional investigations must ideally be preceded by some form of pre-fractionation. However, the more commonly performed methods of crude oil fractionation are often insufficient in the extent to which they separate oils, not allowing defined “molecular” fractions to be obtained and thus hindering more detailed investigations. The following work therefore focused on the development of chromatographic methods to aid in the characterisation of NSO compounds present within crude oils. A novel solid phase extraction (SPE) procedure was developed utilising both ion exchange and adsorption chromatography. The method enabled fractions broadly defined as ‘saturated’ hydrocarbons; ‘aromatic’ hydrocarbons; basic nitrogen compounds; naphthenic acids; phenols and other oxygen-containing species; carbazoles; sulfoxides; and thiophenes, to be isolated reproducibly and quantitatively from relatively small crude oil samples (~ 0.5 g). Assessment of method selectivity with a suite of ‘model’ compounds showed that the resulting fractions were quite well defined, with classes of ‘model’ compounds being isolated within discrete fractions. Application to five crude oils of widely varying properties and origins, such as API gravity (12.1−38.3°), demonstrated the potential for the wide-ranging use of the method. Sample recoveries were high (77−98%) with simple evaporative losses accounting for the majority of sample loss. Repeatability was also high, demonstrated by triplicate analyses of ‘model’ compound mixtures, oils spiked with ‘model’ compounds and oils alone. Subsequent, more detailed, analysis of the fractions using multidimensional gas chromatography-mass spectrometry (GC×GC-MS) and liquid chromatography-highresolution accurate mass-mass spectrometry (LC-HRAM-MS) showed the advantages of the new isolation method. For example, alkylated series (C1-5) of quinolines, carbazoles, fluorenones, dibenzothiophenes and xanthones were identified within their predicted fractions. Furthermore, comparison of mass spectra obtained from GC×GC-MS analyses with reference spectra resulted in the tentative identification of compounds hitherto not previously reported in crude oils, again illustrating the advantage of the isolation method. Novel series of thioxanthones, tocopherols (E vitamins) and terpenoidal sulfoxides and ketones were assigned within the isolated fractions. Following the successful evaluation of the method, the scheme was subsequently employed to investigate the effects of changing geochemical parameters on the composition of isolated NSO-containing compounds. For example, studies of NSO fractions from series of crude oils at different stages of thermal maturity or of biodegradation, led to the identification of a number of potential new molecular markers within the basic-nitrogen and ketone fractions. This work shows clear potential for the developed NSO isolation method to be used in further compositional studies as a tool to aid in geochemical investigations.
2

Petrography and petrochemistry of scapolite in the Grenville of Southern Ontario

Douglas, G. B. 04 1900 (has links)
<p> The aureole surrounding the Loon Lake pluton, notable for the presence of scapolite, is situated in an upper amphibolite facies terrane in the Grenville Province of southern Ontario. Four distinct scapolite-bearing parageneses are found to surround the pluton in more or less concentric zones. Furthest from the pluton a clinopyroxene-scapolite gneiss grades into Ca-amphibole gneiss, Ca-amphibole-biotite gneiss and biotite gneiss. Scapolite is also found in the marbles surrounding the aureole, as well as in all gneisses of the aureole. As the mineralogy of the gneisses change from clinopyroxene through biotite, the textures grade from granoblastic polygonal to a granoblastic polygonal texture modified by abundant acicular and platy minerals. </p> <p> As the pluton is approached, scapolite often assumes a ragged fine-grained nature with alteration to sericite. The whole rock chemistry is characteristic of that derived from a mixture of intermediate volcanics (latite) and carbonate-evaporites. This sequence was undoubtedly deposited in a shallow marine environment. Subsequent metamorphism to upper amphibolite facies produced a band of clinopyroxene gneiss. As the Loon Lake pluton was emplaced increasing temperature and volatiles in an aqueous solution caused the clinopyroxene-scapolite gneiss to undergo retrograde metamorphism and formed the Ca-amphibole, Ca-amphibole-biotite and biotite gneisses. </p> <p> Studies of mineral chemistry indicate that the minerals coexist in equilibrium and that they are related, to some degree, to whole rock composition. As the retrograde metamorphsim occurred elements within the minerals redistributed themselves according to the nature of the new phases produced. Finally, the partitioning between phases followed the ideal binary solution model. Chlorine is found to be partitioned between scapolite, Ca-amphibole and biotite, and all three phases contain chlorine, the relative amounts present being controlled by the crystal structure of the minerals. The relation of Lin and Burley (1973a) between lattice parameter and scapolite composition is confirmed. </p> / Thesis / Master of Science (MSc)
3

Chemical Petrology of the Port Coldwell Alkali Intrusive, Marathon, Ontario

Herdman, David J. 02 1900 (has links)
<p>This study was planned as a combination of detailed field mapping, thin section petrography, whole rock geochemistry and amphibole chemistry of the rocks of the Port Coldwell intrusion. It was hoped that the results of the detailed field mapping would give a clearer picture of the stratigraphy and structure of the intrusion. It was hoped to define the mineralogy and textures of the various phases of the Port Coldwell intrusion enabling a postulation of possible physical conditions under which crystallization occurred. Through whole rock chemical analysis it was hoped to correlate the petrochemistry with the stratigraphy, and so to provide a chemical explanation of the differentiation process. Furthermore, it was hoped to classify the gabbros and through differentiation trends provided by the plots of the analyses, to determine whether the gabbro could be a feasible parent of the other phases of the intrusionThe amphibole found in each phase of the intrusion was to be determined in order to discover elemental trends and to provide corroborating evidence of a differentiation sequence suggested by other sources. </P> / Thesis / Master of Science (MSc)
4

O granito São Timóteo no perfil Monsenhor Bastos, província uranífera de Lagoa Real: mineralogia, geoquímica e fluidos / The São Timóteo granite in Monsenhor Bastos área, Lagoa Real uranium province: mineralogy, geochemistry and fluids

Lucas Eustáquio Dias Amorim 29 February 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Foram estudados corpos graníticos localizados no setor Monsenhor Bastos, porção sudoeste da Província Uranífera de Lagoa Real (PULR). A amostragem foi desenvolvida nas pedreiras de Lagoa Linda (LL), Pedreira Nova (PN) e no granitoide Lajedo (GR) este ultimo que aflora imediatamente a leste da anomalia uranífera AN02. O trabalho focaliza aspectos mineralógicos, geoquímicos, tipológicos e de fluidos desses granitoides, a fim de classificá-los mineralogica, textural e quimicamente. Foram utilizadas as metodologias de petrografia, microssonda eletrônica, geoquímica, termobarometria e estudo de inclusões fluidas (IF). As amostras de granitos apresentam uma paragênese magmática composta por feldspato potássico, plagioclásio, quartzo, piroxênio, ilmenita 1 e zircão. Também foram identificadas duas fases pós-magmáticas compostas por anfibólio, biotita, granada, allanita, ilmenita 2, kainosita, parisita. A ocorrência desses eventos pós-magmáticos propiciou também a formação de uma segunda geração de plagioclásio, zircão, além da formação de mirmequitas e a recristalização de parte dos feldspatos e quartzo. O anfibólio estudado foi formado por alteração do piroxênio em contato com o fluido do primeiro evento pós-magmático. A biotita foi gerada a partir da alteração do anfibólio. No mesmo período de formação do anfibólio foi gerada a allanita, sendo que a parisita e kainosita formaram-se pela alteração desta durante um evento pós-magmático. O evento pós-magmático mais antigo está associado a fluidos ricos em F e Cl, com baixo fO2, pressão próxima a 7 Kbar e temperatura inferior a 700 oC. A parte final desse evento esta associado a soluções alcalinas, ricas em CO2, com temperaturas no intervalo entre 480 C e 600 oC. O estudo de IF permitiu caracterizar fluidos tardios aprisionados no quartzo, que podem estar relacionados com o segundo evento pós-magmático. Esses fluidos, de provável origem hidrotermal, é bastante semelhante ao encontrado por Fuzikawa et al (1988), nas IF dos veios de quartzo que cortam os gnaisses da PULR. A geoquímica permitiu classificar os granitos como sienogranitos / quartzo sienitos, metaluminosos, alcalino-cálcicos (na fronteira dos calci-alcalinos), plotando na série shoshonitica. Também foram classificados como granitos Tipo A, não evoluídos e ferroan. Os dados obtidos não permitem classificar os granitos São Timóteo como rapakivi. Entretanto, a composição desses granitos é equivalente, em termos de elementos maiores e elementos traços, aos granitos rapakivi Cigano e Serra dos Carajás, fases menos especializadas da Suíte Serra dos Carajás. Finalmente, ressalta-se a clara necessidade do desenvolvimento de estudos metalogenéticos, geoquímicos e isotópicos que permitam conhecer com aprofundamento a composição e evolução da Suíte magmática de Lagoa Real e sua relação com as mineralizações de urânio. / Granitic bodies located in the Monsenhor Bastos sector, southwestern portion of the Lagoa Real Uranium Province (PULR) were studied. The sampling was developed in the quarries of Lagoa Linda, Pedreira Nova and Lajedo granitoids that outcrop immediately east of the uranium anomaly (AN02). The work focused on the mineralogical, geochemical, and fluid typological aspects of these granitoids in order to classify them mineralogical, textural and chemically. Petrography, electron microprobe, geochemical, thermobarometry and study of fluid inclusions (FI) methods were performed. The granite shows a magmatic paragenesis with potassium feldspar, plagioclase, quartz, pyroxene, ilmenite and zircon. Two post-magmatic stages composed of amphibole, biotite, garnet, allanite, ilmenite, kainosite, parisite were also identified. The occurrence of post-magmatic events has also led to the formation of a second generation of plagioclase, zircon, besides mirmequites formation and recrystallization of feldspar and quartz. The amphibole was formed by the alteration of pyroxene in contact with the first post-magmatic fluid event. The biotite was generated from the alteration of the amphibole. Allanite was generated in the same period of the amphibole formation, while parisite and kainosite were formed from allanite alteration during a pós-magmatic event.. The post-magmatic oldest event is associated to low fO2, near 7 Kbar pressure, below 700 oC temperature F and Cl rich fluids. The final part of this event is associated to alkaline solutions, rich in CO2, with temperatures between 480 C and 600 oC. The FI studies allowed to characterize late fluids trapped in quartz, which may be related to the second post-magmatic event. This fluid, probably of hydrothermal origin, is quite similar to one found by Fuzikawa et al (1988), in FI found in quartz veins cutting the PULR gneisses. The geochemistry allowed to classify the granites as sienogranites / quartz syenites, metaluminous, alkali-calcic (the border of calc-alkaline) and plotting in shoshonitic field. Granites were also classified as Type A, unevolved and ferroan. The data do not allow the classification of São Timóteo granite as rapakivi type. However, the composition of these granites is equivalent, in terms of major and trace elements, to the Cigano and Serra dos Carajas rapakivi granites, less specialized phases of Serra dos Carajás suite. Finally, it emphasizes the clear need for further metallogenesis, geochemical and isotopic studies depth as to show the composition and evolution of magmatic suite of Lagoa Real and its relationship to uranium mineralization.
5

Geology And Petrology Of Beypazari Granitoids: Yassikaya Sector

Billur, Basak 01 December 2004 (has links) (PDF)
Beypazari Granitoid is a low temperature and shallow-seated batholite intruded the Tepek&ouml / y metamorphic rocks of the Central Sakarya Terrane. Composition of the granitoid varies from granite to diorite. The granitoid is unconformably overlain by Palaeocene and Eocene rock units. Thus the age is probably Late Cretaceous. The Beypazari Granitoid comprises mafic microgranular enclaves. The granitoid mainly consists of quartz, plagioclase, orthoclase and minor amphibole, biotite, chlorite, zircon, sphene, apatite, and opaque minerals. Plagioclase shows sericitation whereas biotite and hornblende, chloritization. Holocrystalline and hypidiomorphic are characteristic textures of the granitoid. Geochemically, the Beypazari Granitoid is calc-alkaline, metaluminous and I-type. REE data indicate that it may have been generated from a source similar to the upper continental crust. The trace element data of the Beypazari Granitoid suggest a volcanic arc tectonic setting. The possible mechanism of Beypazari granitoid is the northdipping subduction of Neo-Tethyan northern branch under Sakarya continent during Late Cretaceous. The Beypazari Granitoid may be related with Galatean volcanic arc granitoids.
6

Petrochemistry of the mafic-rich rocks, Lac des Mille Lacs area, northwestern Ontario / Petrochemistry of the mafic-rich rocks, Lac des Mille Lacs area

Watkinson, David Hugh 05 1900 (has links)
An investigation of the petrology and chemistry of two groups of mafic-rich intrusions from the Lac des Mille Lacs area was carried out. The Quetico group consists of hornblende-rich ultramafic to mafic rocks; the Shebandowan group consists of serpentinized ultramafic rocks and metagabbro. A spectrographic method was employed to quantitatively determine Al2O3, CaO, Co, Cr, Cu, Mn, Ni, Ti, V and Zr in the rocks. This, and other chemical data, indicate that these two spatially related groups, although mineralogically distinct, have similar chemical features, and have apparently crystallized from compositionally similar magmas under different water vapour pressures. Their similarities to ultramafic rocks from other areas provide some implications regarding ultramafic rock types of orogenic areas. / Thesis / Master of Science (MSc)
7

Systém řízení a chránění turbogenerátorů / System control and protection turbo generators

Veverka, Marek January 2008 (has links)
The topic of this thesis is description, analysis and proposal of turbo generator’s control and protection system. The power output of turbo generators is from 3 MVA up to 75 MVA for various industrial sectors. The final proposal is based on the results of this analysis and it consists of a modern control and protection turbo generators systems. This proposal is designed to respect universality, customer’s requirements. And this proposal should be used in many industry branches.

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