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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

Alternative electricity generation : Safripol as a case study / Johan Christi Vorster

Vorster, Johan Christi January 2014 (has links)
Electrical energy supply in South Africa, provided by ESKOM, has become more expensive with regular price increases in the past seven years. Increases on an annual basis have seen the Mega flex tariffs quadruple in the years from 2007 to 2014. ESKOM is the sole supplier of electricity to Safripol, a polymer producer of which the manufacturing facility is located in Sasolburg, South Africa. This study will provide contextual information on what impact the escalation in cost of this utility has on the financial returns of the business. Independent power generation within the boundaries of the manufacturing site has become essential in order to alleviate the impact of inflated electricity costs, by at least 10% of the current total demand from ESKOM. Primary research includes different types of alternative electricity generation techniques that will be able to deliver a practical solution to the business. The means of operation, required resources and cost to produce are set out to provide input into concrete models that are scaled to the potentials applicable to the production facility. Total alternative electricity generation added up to almost half of the current total site electricity demand from ESKOM. This finding was truly beyond the expectations of the case study and clearly set out how understated the potential to generate electricity is within the industrial sector. / MIng (Development and Management Engineering), North-West University, Potchefstroom Campus, 2015
2

Alternative electricity generation : Safripol as a case study / Johan Christi Vorster

Vorster, Johan Christi January 2014 (has links)
Electrical energy supply in South Africa, provided by ESKOM, has become more expensive with regular price increases in the past seven years. Increases on an annual basis have seen the Mega flex tariffs quadruple in the years from 2007 to 2014. ESKOM is the sole supplier of electricity to Safripol, a polymer producer of which the manufacturing facility is located in Sasolburg, South Africa. This study will provide contextual information on what impact the escalation in cost of this utility has on the financial returns of the business. Independent power generation within the boundaries of the manufacturing site has become essential in order to alleviate the impact of inflated electricity costs, by at least 10% of the current total demand from ESKOM. Primary research includes different types of alternative electricity generation techniques that will be able to deliver a practical solution to the business. The means of operation, required resources and cost to produce are set out to provide input into concrete models that are scaled to the potentials applicable to the production facility. Total alternative electricity generation added up to almost half of the current total site electricity demand from ESKOM. This finding was truly beyond the expectations of the case study and clearly set out how understated the potential to generate electricity is within the industrial sector. / MIng (Development and Management Engineering), North-West University, Potchefstroom Campus, 2015
3

Genetic and Epigenetic Determinants of Thrombin Generation Potential : an epidemiological approach / Déterminants génétiques et épigénétiques du potentiel de génération de thrombine par une approche épidémiologique

Rocanin-Arjo, Maria-Ares 20 November 2014 (has links)
Le potentiel de génération thrombine (TGP en anglais) est une nouvelle mesure qui permet de quantifier in vitro l'activité globale de la thrombine reflétant bien les mécanismes in vivo de la coagulation. Ce méthode de dosage est sensible aux déficits de facteurs de coagulation, à la prise d'anti-coagulants et à de nombreux troubles de la coagulation. Au moment où j'ai débuté ma thèse, seuls deux polymorphismes génétiques, tous les deux situés dans le gène F2 codant pour la prothrombine, étaient connus pour influencer la variabilité plasmatique du TGP. Mon projet de thèse avait pour objectifs d'identifier de nouveaux facteurs génétiques, mais également épigénétiques, pouvant influencer les taux plasmatiques de TGP. Dans une première partie, j'ai mené la toute première étude d'association génome-entier (GWAS pour Genome Wide Association Study en anglais) sur 3 biomarqueurs (temps de latence, quantité totale de thrombine produite et niveau maximal de thrombine produite) du TGP dans deux études françaises rassemblant 1267 sujets et j'ai répliqué les résultats les plus significatifs dans deux autres études françaises indépendantes de 1344 sujets. Cette stratégie a permis de mettre en évidence qu'un polymorphisme génétique du gène ORM1 était associé de manière robuste au temps de latence, biomarqueur caractérisant le temps nécessaire pour initier la coagulation après induction. Dans la seconde partie de ma thèse, en suivant une stratégie similaire mais cette fois-ci en étudiant non plus des polymorphismes génétiques mais des marques de méthylation d'ADN, j'ai recherché si des niveaux de méthylation de site CpG, mesurés à partir d'ADN sanguin et couvrant l'ensemble du génome, pouvaient être associés à la variabilité des 3 mêmes biomarqueurs de TGP. Malheureusement, à partir de deux échantillons mis à ma disposition et rassemblant 425 sujets, je n'ai pas pu mettre en évidence d'association robuste entre des marques de méthylation sanguine et la génération trombine. / Thrombin Generation Potential (TGP) is a promising in vitro measurement that allows quantifying thrombin activity, in a close way to what happens in vivo. It is sensitive to coagulation factors deficiencies, anticoagulant proteins and is associated to thrombotic disorders. There exists two polymorphisms located in the F2 (prothrombin) gene known to influence TGP levels, and altogether they explain 11.3% of the TGP inter-individual variability. With the aims of identifying novel genetic and epigenetic factors that influence TGP variability, I have performed two different studies in the present work. First, I conducted the first genome-wide association study for the three TGP biomarkers (ETP, Peak and Lagtime) using imputation data from two French studies. The most significant single nucleotide polymorphisms (SNPs) were then replicated in two independent French studies. This analysis lead to the discovery of ORM1 as a new gene participating to the control of TGP. Second, I followed a similar strategy using this time whole blood DNA methylation levels at CpG sites to identify DNA methylation marks involved in TGP variability. I analyzed the association between methylation-wide patterns from a French study and a French-Canadian families measured for TGP. Unfortunately, I did not identify robust associations between whole DNA methylation levels and thrombin generation.
4

Caracterização geoquímica de rochas geradoras do intervalo Cretáceo-Terciário da Bacia de Santos, Brasil.

Balbinot, Mariana January 2012 (has links)
A Bacia de Santos é uma das principais bacias brasileiras para exploração e produção de hidrocarbonetos, e vem recebendo grandes investimentos em pesquisa nos últimos anos. O estudo das rochas geradoras serve como importante ferramenta para o estudo de modelos de geração, explusão e migração de hidrocarbonetos e na identificação de sistemas petrolíferos. O principal objetivo deste trabalho é a identificação de intervalos e áreas com maior potential para a geração de hidrocarbonetos dentro do pacote sedimentar estudado (Cretáceo-Terciário). As amostras de calha de 6 poços exploratórios, obtidas junto à Agência Nacional de Petróleo, Gás Natural e Biocombustíveis (ANP), foram analisadas através da geoquímica orgânica (Carbono Orgânico Total (COT), Pirólise Rock Eval e análise de Biomarcadores) e da petrologia orgânica (Reflectância da Vitrinita e Palinofácies) e foram interpretadas juntamente com os resultados do estudo de outros 10 poços exploratórios, obtidos pela Geochemical Solutions International cedidos para este trabalho. Esses 16 poços formam um perfil strike SW-NE que recobre praticamente toda a extensão da bacia. Amostras das formações Marambaia, Juréia, Santos, Itajaí-Açu, Itanhaem, Guarujá e Florianópolis foram analisadas, apresentando resultados semelhantes para o tipo de matéria orgânica, sua origem e ambiente deposicional (querogênio tipo II e III, originado pela mistura de material de origem terrestre e marinha depositado em ambiente transicional levemente oxidante). Os perfis analisados identificaram dois intervalos de maior conteúdo de carbono orgânico, maturação e potencial de geração de petróleo, um entre 2500 e 3000 metros de profundidade, que pode estar relacionado a eventos transgressivos do Terciário, e outro entre 4000 a 5000 metros de profundidade, possivelmente relacionado a um importante evento transgressivo de caráter regional ocorrido durante o Turoniano. A matéria orgânica encontrada nos poços situados na região sudoeste do perfil foi a que apresentou as melhores condições para a geração de hidrocarbonetos, tornando-se mais empobrecida na direção nordeste. Com base nos resultados geoquímicos e petrográficos obtidos, a matéria orgânica presente na Formação Itajaí-Açu possui o melhor potencial para geração de hidrocarbonetos, principalmente na porção basal do intervalo, na região sudoeste da bacia. / The Santos Basin is one of the main Brazilian sedimentary basin for hydrocarbon exploration and production and has been the focus of major geological research on hydrocarbon occurrences in recent years. Source rock studies are important tools for construction of hydrocarbon generation, expulsion and migration models of the basin and for identifying petroleum systems. The main objective of the present study is to identify areas and intervals with hydrocarbon generation potential inside the sedimentary sequence studied (Cretaceous-Tertiary). Cutting samples from 6 petroleum exploration wells obtained from the National Agency of Petroleum, Natural Gas and Biofuels (ANP) were analysed by organic geochemical methods (Total Organic Carbon (TOC), Rock Eval Pyrolysis and Biomarkers analysis) and organic petrography (Vitrinite Reflectance and Palynofacies) and were interpreted together with results from organic geochemical studies on samples from 10 addictional petroleum exploratory wells obtained from Geochemical Solution International (GSI), provided for this study. These 16 wells form a SW-NE strike section, that covers the basin almost completely in this direction. The samples from Marambaia, Juréia, Santos, Itajaí-Açu, Itanhaem, Guarujá and Florianópolis formations show similar results in regard to organic matter type, its origin and depositional paleoenvironment (type II-III kerogen, indicating a contribution of terrestrial and marine material, deposited in a transitional and slightly oxic environment). The stratigraphic profiles analysed identify two intervals with relatively high organic matter content, maturation and hydrocarbon generation potential, one between 2500 and 3000 meters depth, perhaps related to a Tertiary transgressive event and the other one between 4000 and 5000 meters depth, possibly related to an important regional transgressive event, which occurred during the Turonian. The organic matter encountered in the well samples located in the southwest of the SW-NE section has the best potential for hydrocarbon generation, whereas the organic matter of well samples located in the northwest direction has less potential to form hydrocarbons. Based on the results of the present study, the organic matter present in the Itajaí-Açu Formation has the best potential for hydrocarbon generation, in particular in the basal part of the formation in the southwest region of the basin.
5

Caracterização geoquímica de rochas geradoras do intervalo Cretáceo-Terciário da Bacia de Santos, Brasil.

Balbinot, Mariana January 2012 (has links)
A Bacia de Santos é uma das principais bacias brasileiras para exploração e produção de hidrocarbonetos, e vem recebendo grandes investimentos em pesquisa nos últimos anos. O estudo das rochas geradoras serve como importante ferramenta para o estudo de modelos de geração, explusão e migração de hidrocarbonetos e na identificação de sistemas petrolíferos. O principal objetivo deste trabalho é a identificação de intervalos e áreas com maior potential para a geração de hidrocarbonetos dentro do pacote sedimentar estudado (Cretáceo-Terciário). As amostras de calha de 6 poços exploratórios, obtidas junto à Agência Nacional de Petróleo, Gás Natural e Biocombustíveis (ANP), foram analisadas através da geoquímica orgânica (Carbono Orgânico Total (COT), Pirólise Rock Eval e análise de Biomarcadores) e da petrologia orgânica (Reflectância da Vitrinita e Palinofácies) e foram interpretadas juntamente com os resultados do estudo de outros 10 poços exploratórios, obtidos pela Geochemical Solutions International cedidos para este trabalho. Esses 16 poços formam um perfil strike SW-NE que recobre praticamente toda a extensão da bacia. Amostras das formações Marambaia, Juréia, Santos, Itajaí-Açu, Itanhaem, Guarujá e Florianópolis foram analisadas, apresentando resultados semelhantes para o tipo de matéria orgânica, sua origem e ambiente deposicional (querogênio tipo II e III, originado pela mistura de material de origem terrestre e marinha depositado em ambiente transicional levemente oxidante). Os perfis analisados identificaram dois intervalos de maior conteúdo de carbono orgânico, maturação e potencial de geração de petróleo, um entre 2500 e 3000 metros de profundidade, que pode estar relacionado a eventos transgressivos do Terciário, e outro entre 4000 a 5000 metros de profundidade, possivelmente relacionado a um importante evento transgressivo de caráter regional ocorrido durante o Turoniano. A matéria orgânica encontrada nos poços situados na região sudoeste do perfil foi a que apresentou as melhores condições para a geração de hidrocarbonetos, tornando-se mais empobrecida na direção nordeste. Com base nos resultados geoquímicos e petrográficos obtidos, a matéria orgânica presente na Formação Itajaí-Açu possui o melhor potencial para geração de hidrocarbonetos, principalmente na porção basal do intervalo, na região sudoeste da bacia. / The Santos Basin is one of the main Brazilian sedimentary basin for hydrocarbon exploration and production and has been the focus of major geological research on hydrocarbon occurrences in recent years. Source rock studies are important tools for construction of hydrocarbon generation, expulsion and migration models of the basin and for identifying petroleum systems. The main objective of the present study is to identify areas and intervals with hydrocarbon generation potential inside the sedimentary sequence studied (Cretaceous-Tertiary). Cutting samples from 6 petroleum exploration wells obtained from the National Agency of Petroleum, Natural Gas and Biofuels (ANP) were analysed by organic geochemical methods (Total Organic Carbon (TOC), Rock Eval Pyrolysis and Biomarkers analysis) and organic petrography (Vitrinite Reflectance and Palynofacies) and were interpreted together with results from organic geochemical studies on samples from 10 addictional petroleum exploratory wells obtained from Geochemical Solution International (GSI), provided for this study. These 16 wells form a SW-NE strike section, that covers the basin almost completely in this direction. The samples from Marambaia, Juréia, Santos, Itajaí-Açu, Itanhaem, Guarujá and Florianópolis formations show similar results in regard to organic matter type, its origin and depositional paleoenvironment (type II-III kerogen, indicating a contribution of terrestrial and marine material, deposited in a transitional and slightly oxic environment). The stratigraphic profiles analysed identify two intervals with relatively high organic matter content, maturation and hydrocarbon generation potential, one between 2500 and 3000 meters depth, perhaps related to a Tertiary transgressive event and the other one between 4000 and 5000 meters depth, possibly related to an important regional transgressive event, which occurred during the Turonian. The organic matter encountered in the well samples located in the southwest of the SW-NE section has the best potential for hydrocarbon generation, whereas the organic matter of well samples located in the northwest direction has less potential to form hydrocarbons. Based on the results of the present study, the organic matter present in the Itajaí-Açu Formation has the best potential for hydrocarbon generation, in particular in the basal part of the formation in the southwest region of the basin.
6

Caracterização geoquímica de rochas geradoras do intervalo Cretáceo-Terciário da Bacia de Santos, Brasil.

Balbinot, Mariana January 2012 (has links)
A Bacia de Santos é uma das principais bacias brasileiras para exploração e produção de hidrocarbonetos, e vem recebendo grandes investimentos em pesquisa nos últimos anos. O estudo das rochas geradoras serve como importante ferramenta para o estudo de modelos de geração, explusão e migração de hidrocarbonetos e na identificação de sistemas petrolíferos. O principal objetivo deste trabalho é a identificação de intervalos e áreas com maior potential para a geração de hidrocarbonetos dentro do pacote sedimentar estudado (Cretáceo-Terciário). As amostras de calha de 6 poços exploratórios, obtidas junto à Agência Nacional de Petróleo, Gás Natural e Biocombustíveis (ANP), foram analisadas através da geoquímica orgânica (Carbono Orgânico Total (COT), Pirólise Rock Eval e análise de Biomarcadores) e da petrologia orgânica (Reflectância da Vitrinita e Palinofácies) e foram interpretadas juntamente com os resultados do estudo de outros 10 poços exploratórios, obtidos pela Geochemical Solutions International cedidos para este trabalho. Esses 16 poços formam um perfil strike SW-NE que recobre praticamente toda a extensão da bacia. Amostras das formações Marambaia, Juréia, Santos, Itajaí-Açu, Itanhaem, Guarujá e Florianópolis foram analisadas, apresentando resultados semelhantes para o tipo de matéria orgânica, sua origem e ambiente deposicional (querogênio tipo II e III, originado pela mistura de material de origem terrestre e marinha depositado em ambiente transicional levemente oxidante). Os perfis analisados identificaram dois intervalos de maior conteúdo de carbono orgânico, maturação e potencial de geração de petróleo, um entre 2500 e 3000 metros de profundidade, que pode estar relacionado a eventos transgressivos do Terciário, e outro entre 4000 a 5000 metros de profundidade, possivelmente relacionado a um importante evento transgressivo de caráter regional ocorrido durante o Turoniano. A matéria orgânica encontrada nos poços situados na região sudoeste do perfil foi a que apresentou as melhores condições para a geração de hidrocarbonetos, tornando-se mais empobrecida na direção nordeste. Com base nos resultados geoquímicos e petrográficos obtidos, a matéria orgânica presente na Formação Itajaí-Açu possui o melhor potencial para geração de hidrocarbonetos, principalmente na porção basal do intervalo, na região sudoeste da bacia. / The Santos Basin is one of the main Brazilian sedimentary basin for hydrocarbon exploration and production and has been the focus of major geological research on hydrocarbon occurrences in recent years. Source rock studies are important tools for construction of hydrocarbon generation, expulsion and migration models of the basin and for identifying petroleum systems. The main objective of the present study is to identify areas and intervals with hydrocarbon generation potential inside the sedimentary sequence studied (Cretaceous-Tertiary). Cutting samples from 6 petroleum exploration wells obtained from the National Agency of Petroleum, Natural Gas and Biofuels (ANP) were analysed by organic geochemical methods (Total Organic Carbon (TOC), Rock Eval Pyrolysis and Biomarkers analysis) and organic petrography (Vitrinite Reflectance and Palynofacies) and were interpreted together with results from organic geochemical studies on samples from 10 addictional petroleum exploratory wells obtained from Geochemical Solution International (GSI), provided for this study. These 16 wells form a SW-NE strike section, that covers the basin almost completely in this direction. The samples from Marambaia, Juréia, Santos, Itajaí-Açu, Itanhaem, Guarujá and Florianópolis formations show similar results in regard to organic matter type, its origin and depositional paleoenvironment (type II-III kerogen, indicating a contribution of terrestrial and marine material, deposited in a transitional and slightly oxic environment). The stratigraphic profiles analysed identify two intervals with relatively high organic matter content, maturation and hydrocarbon generation potential, one between 2500 and 3000 meters depth, perhaps related to a Tertiary transgressive event and the other one between 4000 and 5000 meters depth, possibly related to an important regional transgressive event, which occurred during the Turonian. The organic matter encountered in the well samples located in the southwest of the SW-NE section has the best potential for hydrocarbon generation, whereas the organic matter of well samples located in the northwest direction has less potential to form hydrocarbons. Based on the results of the present study, the organic matter present in the Itajaí-Açu Formation has the best potential for hydrocarbon generation, in particular in the basal part of the formation in the southwest region of the basin.

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