Dissertations / Theses: 'Liseed Oil'

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DEHONOR, MARQUEZ ETHNICE 553799, and MARQUEZ ETHNICE DEHONOR. "Evaluación de los parámetros de sensado de compuestos poliméricos con nanotubos de carbono, respecto a la composición de la matriz polimérica a base de aceites de linaza xilitolado y epoxidado." Tesis de doctorado, Universidad Autónoma del Estado de México, 2019. http://hdl.handle.net/20.500.11799/105651.

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Tesis de Doctorado en Ciencia de Materiales
Este trabajo consistió en la obtención de sensores de Compuestos Poliméricos Conductores (CPC), a base de aceites vegetales y Nanotubos de Carbono de Pared Múltiple (NTCPM); así como su evaluación a la presencia de diferentes disolventes.

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Mohammed, Sani D. "Social and environmental disclosures : a comparative analysis of listed Nigerian and UK oil and gas companies." Thesis, Abertay University, 2016. https://rke.abertay.ac.uk/en/studentTheses/5e9bd304-82f0-4be7-b151-01fcc20019e2.

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Exploration, production and marketing of oil and gas by listed Nigerian oil and gas companies are fraught with lots of negative social and environmental impacts. Corporate social disclosure is a medium employed by corporations to communicate their impacts and commitments to the society and environment. Therefore, the main aim of this study is to describe and explain social and environmental disclosure practices by listed Nigerian oil and gas companies as gauged with disclosure by listed UK oil and gas companies for the period 2004-2013. The objectives are to determine the nature of disclosures by sampled companies, measure and analyse quantity and quality of the disclosures, analyse trends of the disclosures, find out differences in the disclosures and to explore the effects of corporate characteristics on the disclosures. Content analysis of annual reports and accounts and sustainability reports, scoring quality of disclosures based on Global Reporting Initiative disclosure guidelines, two samples t-tests and Panel Corrected Standard Errors (PCSE) regression analysis were employed to achieve the aim and objectives of the study. Legitimacy debate and vulnerability and exploitability analytical framework were espoused to develop a theoretical framework to underpin the study. Results indicate Nigerian companies making disclosure on fewer social and environmental aspects than UK companies. Quantity and quality of disclosure by Nigerian companies are low compared to UK companies. While quantity of disclosure by both showed increasing trends, quality of disclosure depicted decreasing trends. Sampled companies are found complying with mandatory social disclosure. Corporate size, leverage, efficiency and liquidity are found significant in explaining disclosures by sampled companies. Low quantity and quality of disclosure by listed Nigerian oil and gas companies is indicating low social accountability. This result may be useful to policy makers in the industry to dialogue with managers of the companies on the importance of their social accountability to overall national sustainable development efforts. Likewise, policy makers may put in place regulatory and enforcement mechanisms on social disclosures as mandating disclosure is found effective. Disclosure practices by listed Nigerian oil and gas companies portrayed the significance of colonial relationship between Nigeria and the UK. The use of modified words counts content analysis, and the theoretical framework that underpins the study might be of significance in this study in particular and social disclosure studies in general.

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Alenezi, Marim. "The impact of exchange rate, interest rate and oil price fluctuations on stock returns of GCC listed companies." Thesis, University of Plymouth, 2015. http://hdl.handle.net/10026.1/3658.

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Exchange rate risk, interest rate risk and oil price fluctuations are the most demonstrated risks in the GCC (Gulf Cooperation Council) countries (Arouri and Nguyen, 2010). Research, however, in this area is still underdeveloped. The importance of this study is to contribute to this research gap. This research aims to show how these three risks affect firms' market values by examining 473 listed firms in Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and United Arab Emirates for the period January 2007 to June 2012. The research further examines the determinants of these risks. The study uses the AR (1) EGARCH-M model. The results indicate that stock returns in GCC countries are influenced by the exchange rate risk, interest rate risk and oil price risk. However, the exposure was highest for exchange rate risk and lowest for interest rate risk. While the effects of these risks were mixed, overall, exchange rate risk and oil price risk showed more positive significance as compared to the interest rate risk that showed more negatively significant effect on firm values. The level of the effect of these risk also differed from country to country. However, firms in United Arab Emirates revealed the highest exposure to all the three risks while those in Saudi Arabia showed the least exposed to the three risks. Oman firms also showed high exposure to exchange rate and interest rate risks. The segregated results overall showed lower exposure of financial firms as compared to non-financial firms. However, the non-financial firms in Bahrain were more exposed to the risks than the financial firms. In Saudi Arabia, the financial firms revealed the least exposure to the risk suggesting effective risk management practices. In addition, foreign operations and firm size had a significant influence on the extent of the firms’ exposure to all the three risks. Leverage also influenced the level of exposure to interest rate risk. Profitability, growth and liquidity did not reveal a significant influence on the level of exposure. Further, increasing the risk does not lead to increased returns in most of the GCC countries. The risk-return parameters were largely negative. However, positive news increases return volatility more than negative news in most countries. Also, the current volatility of most GCC firms’ returns are time varying, are a function or past innovation and past volatility. The volatility of stock returns, which is affected by changes in the risk factors, could demonstrate the non-prioritisation of risk management by firms.

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Bala, Masud. "Effects of IFRS adoption on the financial statements of Nigerian listed entities : the case of oil and gas companies." Thesis, Abertay University, 2015. https://rke.abertay.ac.uk/en/studentTheses/2a81c014-18a6-4372-90c8-985f6ad8e0d3.

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On 28 July 2010, the Nigerian Federal Executive Council approved January 1, 2012 as the effective date for the convergence of Nigerian Statement of Accounting Standards (SAS) or Nigerian GAAP (NG-GAAP) with International Financial Reporting Standards (IFRS). By this pronouncement, all publicly listed companies and significant public interest entities in Nigeria were statutorily required to issue IFRS based financial statements for the year ended December, 2012. This study investigates the impact of the adoption of IFRS on the financial statements of Nigerian listed Oil and Gas entities using six years of data which covers three years before and three years after IFRS adoption in Nigeria and other African countries. First, the study evaluates the impact of IFRS adoption on the Exploration and Evaluation (E&E) expenditures of listed Oil and Gas companies. Second, it examines the impact of IFRS adoption on the provision for decommissioning of Oil and Gas installations and environmental rehabilitation expenditures. Third, the study analyses the impact of the adoption of IFRS on the average daily Crude Oil production cost per Barrel. Fourth, it examines the extent to which the adoption and implementation of IFRS affects the Key Performance Indicators (KPIs) of listed Oil and Gas companies. The study further explores the impact of IFRS adoption on the contractual relationships between Nigerian Government and Oil and Gas companies in terms of Joint Ventures (JVs) and Production Sharing Contracts (PSCs) as it relates to taxes, royalties, bonuses and Profit Oil Split. A Paired Samples t-test, Wilcoxon Signed Rank test and Gray’s (Gray, 1980) Index of Conservatism analyses were conducted simultaneously where the accounting numbers, financial ratios and industry specific performance measures of GAAP and IFRS were computed and analysed and the significance of the differences of the mean, median and Conservatism Index values were compared before and after IFRS adoption. Questionnaires were then administered to the key stakeholders in the adoption and implementation of IFRS and the responses collated and analysed. The results of the analyses reveal that most of the accounting numbers, financial ratios and industry specific performance measures examined changed significantly as a result of the transition from GAAP to IFRS. The E&E expenditures and the mean cost of Crude Oil production per barrel of Oil and Gas companies increased significantly. The GAAP values of inventories, GPM, ROA, Equity and TA were also significantly different from the IFRS values. However, the differences in the provision for decommissioning expenditures were not statistically significant. Gray’s (Gray, 1980) Conservatism Index shows that Oil and Gas companies were more conservative under GAAP when compared to the IFRS regime. The Questionnaire analyses reveal that IFRS based financial statements are of higher quality, easier to prepare and present to management and easier to compare among competitors across the Oil and Gas sector but slightly more difficult to audit compared to GAAP based financial statements. To my knowledge, this is the first empirical research to investigate the impact of IFRS adoption on the financial statements of listed Oil and Gas companies. The study will therefore make an enormous contribution to academic literature and body of knowledge and void the existing knowledge gap regarding the impact and implications of IFRS adoption on the financial statements of Oil and Gas companies.

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Kountourakis, Stenya [Verfasser], and Markus [Akademischer Betreuer] Taube. "Chinese Listed National Oil Companies: an Analysis of the Minor Shareholder within an Agency Theory Framework / Stenya Kountourakis ; Betreuer: Markus Taube." Duisburg, 2020. http://d-nb.info/121759499X/34.

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Pacheco, Jos? Marcos Leite. "An?lise de Sustentabilidade em Projetos de Instala??es de Produ??o de Petr?leo." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12974.

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A proposal for a global analysis of sustainability in projects related in oil facilities is presented. By considering economic, environmental and social aspects in the early stages of design, the suggested method is more comprehensive and can be used to complement the analysis commonly applied in the petroleum industry, such as: Study of Technical and Economic Feasibility; Environmental Impact Assessment and Risk Analysis. Several authors, associations, certification bodies and oil companies suggest different approaches to study sustainability in some specific activities (or industries). In this study, a checklist of significant sustainability aspects for the oil industry (surface facilities) was assembled. In addition, a matrix was developed to assess the sustainability items relevant to these projects. In this work, the checklist interacts with the matrix to perform a "Preliminary Analysis of Sustainability of the Enterprise" (APSE). This method allows the identification of aspects that contribute significantly to global sustainability. From this analysis, which includes economic, social and environmental aspects, is built a report that is used to analyze qualitatively and quantitatively the impact of the sustainability aspects of the project. In this analysis are identified items that strongly influence the economic, social or environmental aspects and evaluated alternatives that can increase the overall sustainability of the project. Finally, the alternatives that can be used to indicate the most sustainable option are identified. This method was applied in a project (design) of a small offshore platform. This case study shows how the APSE can contribute to the identification of sustainability initiatives for the enterprise. The results showed that relevant aspects can contribute decisively to global sustainability. Finally, it was observed that the proposed method can contribute to increased rates of sustainability, even after application of analysis commonly used in these projects
Apresenta-se uma proposta para a an?lise global da sustentabilidade em projetos relacionados ?s instala??es de petr?leo. Por considerar aspectos econ?micos, ambientais e sociais nas etapas iniciais do projeto (design), o m?todo sugerido ? mais abrangente e pode ser utilizado para complementar as an?lises comumente aplicadas na ind?stria do petr?leo, como: Estudo de Viabilidade T?cnica e Econ?mica - EVTE; Estudo de Impacto Ambiental - EIA e as an?lises de riscos. V?rios autores, associa??es, ?rg?os certificadores e empresas de petr?leo sugerem diferentes abordagens para estudar a sustentabilidade em algumas atividades (ou ind?strias) espec?ficas. Neste trabalho, foi montada uma lista de verifica??o com aspectos de sustentabilidade significativos para a ind?stria do petr?leo (instala??es de superf?cie). Al?m disso, foi elaborada uma matriz para avaliar os itens relevantes para sustentabilidade nestes empreendimentos. Neste trabalho, a lista de verifica??o interage com a matriz para a realiza??o de uma An?lise Preliminar de Sustentabilidade do Empreendimento (APSE). Esta proposta permite identificar aspectos que contribuam significativamente para a sustentabilidade global. A partir desta an?lise, que inclui aspectos econ?micos, sociais e ambientais, ? constru?do um relat?rio que ? utilizado para analisar qualitativamente e quantitativamente os impactos dos aspectos na sustentabilidade do empreendimento. Nesta an?lise s?o identificados itens que influenciam fortemente os aspectos econ?micos, sociais ou ambientais e s?o avaliadas as alternativas que possam incrementar a sustentabilidade global do empreendimento. Finalmente, s?o identificadas as alternativas que podem ser utilizados para indicar a op??o mais sustent?vel. A APSE foi aplicada num projeto de uma pequena plataforma offshore. Este estudo de caso mostra como a APSE pode contribuir para a identifica??o de a??es pr?-sustentabilidade para o empreendimento. Os resultados mostraram que aspectos relevantes contribuem decisivamente para a sustentabilidade global. Finalmente, observou-se que o m?todo proposto pode contribuir para o aumento dos ?ndices de sustentabilidade, mesmo ap?s a aplica??o das an?lises comumente utilizadas nestes empreendimentos

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Ribeiro, Fernanda Pinheiro de Carvalho. "Obten??o de rutina ricinoleato atrav?s da rea??o de esterifica??o com ?leo de mamona." Universidade Estadual de Feira de Santana, 2016. http://localhost:8080/tede/handle/tede/475.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES
The flavonoid rutin (3-0-rutinos?deo-quercetin) stands out among the natural products as a promising alternative in the fight against degenerative diseases and related to aging. However, the low solubility and stability thereof in different media, especially lipophilic limited applications in pharmaceutical preparations. The biocatalytic transformation by enzymatic acylation has been suggested by several authors, with good reaction yields. In this sense, the objective of this study was to promote the enzymatic acylation of rutin, using castor oil as acylating agent and lipase as a catalyst, to characterize the formed product, estimate the efficiency of bioconversion, and to investigate in vitro the antioxidant activity and cytotoxic effect opposite the reaction product Vero cells. The catalytic transformation occurred at 50?C for 120 hours. The product was subjected to column chromatography, followed by filtration by Sephadex LH-20. The chemical structure of rutin-O-ricinoleate was determined by Nuclear Magnetic Resonance (NMR) 1H and 13C and by liquid chromatography / mass spectroscopy (HPLC/MS). In another experiment, it was observed the formation of the ester content by High Performance Liquid Chromatography coupled to a detector diode arrangements (HPLC-DAD) under conditions which allow assessing the reaction yield over 120 hours. The analytical method proposed has been validated considering the linearity parameters, accuracy, precision, limit of quantification and detection proved to be suitable for quantification of ricinoleato rutin. It was found by this method that the reaction product maintained the antioxidant capacity of rutin and there was no evidence of cytotoxicity.
O flavonoide rutina (quercetina-3-0-rutinos?deo) se destaca entre os produtos naturais como uma alternativa promissora no combate ?s doen?as degenerativas e relacionadas ao envelhecimento. No entanto, a baixa solubilidade e estabilidade da mesma em diferentes meios, especialmente lipof?licos, limitam as aplica??es em prepara??es farmac?uticas. A transforma??o biocatal?tica, atrav?s da acila??o enzim?tica, tem sido sugerida por diversos autores, com bons rendimentos reacionais. Neste sentido, o objetivo do presente trabalho foi promover a acila??o enzim?tica da rutina, utilizando ?leo de mamona como agente acilante e lipase como catalizador, caracterizar o produto formado, estimar o rendimento da bioconvers?o, al?m de investigar in vitro a atividade antioxidante e o efeito citot?xico do produto reacional frente ?s c?lulas Vero. A transforma??o catal?tica ocorreu em temperatura de 50?C, durante 120 horas. O produto foi submetido ? cromatografia em coluna, seguida de filtra??o por Sephadex LH-20. A estrutura qu?mica da rutina-O-ricinoleato, foi determinada por Resson?ncia Magn?tica Nuclear (RMN) 1H e de 13C e por cromatografia l?quida/espectroscopia de massas (CLAE/EM). Em outro experimento, foi verificado o teor de forma??o do ?ster por Cromatografia ? L?quidos de Alta Efici?ncia acoplado a um detector de arranjos Diodos (CLAE-DAD), em condi??es que permitiram avaliar o rendimento reacional ao longo de 120 horas. O m?todo anal?tico proposto foi validado considerando os par?metros de linearidade, exatid?o, precis?o, Limites de quantifica??o e de detec??o mostrando-se adequado para a quantifica??o da rutina ricinoleato. Verificou-se pelos m?todos avaliados, que o produto reacional manteve a capacidade antioxidante da rutina e que n?o houve evid?ncia de citotoxicidade.

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Siqueira, Mariana de. "An?lise jur?dico-constitucional do fomento aos campos maduros de produ??o de petr?leo no Brasil." Universidade Federal do Rio Grande do Norte, 2009. http://repositorio.ufrn.br:8080/jspui/handle/123456789/13897.

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Instituto Brasileiro de Petr?leo, G?s e Biocombust?veis
The oil activities in Brazil had been started in an intensive way in the end of the 30 s and in the beginning of the 40 s. Many of the brazilians fields discovered in the past are nowadays in decline. They are called ―mature fields‖. These fields, because of the decline situation that characterizes them, are not interesting for the majors. The majors want the big fields and big productions. On the other hand, they could be interesting for the small and medium enterprises. The mature oil fields are instruments of development, they have oil and the oil production is an activity connected with many social and economics benefits: jobs, taxes, royalties, etc. The Brazilian State, in this context, needs to realize actions to promote the activities in the mature oil fields, especially with the work of the small and mediums enterprises. Many of the onshore brazilian mature fields are located at the Northeast, a region matched by many social and economic problems. The activities in the mature fields of the Northeast Region could solve some of its problems. The present research analyses the mature oil fields and its situations in Brazil, making criticisms and suggestions. The methodology adopted is theoretical and descriptive, with literature review, case law and legislation (Constitui??o Federal de 1988, ―Law of the Oil‖). This research examines the following points: mature fields rounds and its documents, name and definition of the mature fields, definition of small and medium enterprises, environmental aspects, concentration of certain activities of the sector and the royalties
As atividades do petr?leo no pa?s foram iniciadas de forma mais intensa no final dos anos 30 e in?cio dos anos quarenta. Muitos dos campos de petr?leo descobertos no passado hoje se encontram em decl?nio produtivo, s?o os chamados ―campos maduros de petr?leo‖. Estes campos, em decorr?ncia do decl?nio em sua produ??o, n?o se revelam interessantes ?s grandes empresas de petr?leo. Grandes empresas desejam grandes campos e grandes produ??es. Por outro lado, podem os campos maduros se revelar interessantes aos empreendedores de menor porte. Os campos maduros, ainda que em decl?nio, possuem petr?leo e o petr?leo ? recurso energ?tico demasiadamente relevante. A produ??o de petr?leo, mesmo em campos declinantes, ? atividade ligada a in?meros benef?cios sociais e econ?micos: gera empregos direitos e indiretos, promove o recolhimento de tributos, o pagamento de royalties, dentre outros. O Estado brasileiro, neste contexto, necessita realizar a??es que promovam a continua??o da produ??o em campos maduros, especialmente atrav?s do ingresso de empreendedores de menor porte. Muitos dos campos maduros onshore se encontram no Nordeste brasileiro, regi?o marcada por s?rios problemas econ?micos e sociais e por uma intensa desigualdade. As atividades de produ??o de petr?leo nos campos maduros nordestinos podem resolver alguns destes problemas, fato este que ressalta a import?ncia do fomento ? continua??o destas atividades nestes campos. A presente pesquisa, atentando para a relev?ncia do fomento ? continua??o das atividades desenvolvidas nos campos maduros de petr?leo, se debru?a sobre seu estudo e atual realidade, formulando cr?ticas e sugest?es, em especial no que diz respeito ? entrada de empreendedores de menor porte no setor. Para isto, utiliza a metodologia do tipo te?rico-descritiva, com an?lise bibliogr?fica, jurisprudencial e normativa. Neste ?ltimo caso, a Constitui??o Federal de 1988 e a ―Lei do Petr?leo‖ se destacam. S?o aqui especificamente analisadas as licita??es at? hoje efetuadas em torno de ?reas contendo campos maduros de petr?leo, seus editais e contratos de concess?o. A pesquisa em quest?o ainda se ocupa das seguintes tem?ticas: conceito e denomina??o dos campos de petr?leo com produ??o declinante, necessidade de formula??o de um conceito para a express?o ―empreendedores petrol?feros de menor porte‖, licenciamento ambiental no setor do petr?leo, passivos ambientais atinentes aos campos maduros, concentra??o de determinadas atividades do setor junto ? Petrobras e royalties e necessidade de sua cobran?a em percentual reduzido

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Costa, Antonio Rufino da. "An?lise da efici?ncia de contratos de servi?os de elevada especificidade terceirizados pela petrobras." Universidade Federal do Rio Grande do Norte, 2013. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12078.

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The definition of the boundaries of the firms is subject that has occupied the organizational theorists long ago, being the seminal work of Coase (1937) indicated as the trigger for one theoretical evolution, with emphasis on governance structures, which led to a modern theory of incomplete contracts. The Transaction Cost Economics (TCE) and Agency Theory arise within this evolution, being widely used in studies related to the theme. Empirically, data envelopment analysis (DEA) has established itself as a suitable tool for analysis of efficiency. Although TCE argues that specific assets must be internalized, recent studies outside the mainstream of theory show that, often, firms may decide, for various reasons, hire them on the market. Researches on transaction costs face with the unavailability of information and methodological difficulties in measuring their critical variables. There`s still the need for further methodological deepening. The theoretical framework includes classic works of TCE and Agency Theory, but also more recent works, outside the mainstream of TCE, which warn about the existence of strategies in use of specific assets that aren`t necessarily aligned with the classical ideas of TCE. The Brazilian oil industry is the focus of this thesis, that aimed to evaluate the efficiency of contracts involving high specificity service outsourced by Petrobras. In order to this, we made the categorization of outsourced services in terms of specificity, as well the description of services with higher specificity. Then, we verified the existence of relationship between the specificity of services and a number of variables, being found divergent results than those that are preached by the mainstream of TCE. Then, we designed a DEA model to analyze the efficiency in the use of onshore drilling rigs, identified among the services of highest specificity. The next step was the application of the model to evaluate the performance of drilling rigs contracts. Finally, we verified the existence of relationship between the efficiency of contracts and a number of variables, being found, again, results not consistent with the theory mainstream. Regarding to analyze of efficiency of drilling rigs contracts, the model developed is compatible with what is found in academic productions in efficiency of drilling rigs. The results on efficiency show a wide range of scores, with efficiencies ranging from 31.79% to 100%, being low the sample efficiency average. There is consonance between the model results and the practices adopted by Petrobras. The results strengthen the DEA as an important tool in studies of efficiency with possibility to use for analysis other types of contracts. In terms of theoretical findings, the results reinforce the arguments that there are situations in which the strategies of the organizations, in terms of use of assets and services of high specificity, do not necessarily follow what is recommended by the mainstream of TCE
A defini??o das fronteiras da firma ? tema que tem ocupado os te?ricos organizacionais h? bastante tempo, sendo o trabalho seminal de Coase (1937) apontado como desencadeador de uma evolu??o te?rica, com ?nfase nas estruturas de governan?a, que desemboca numa moderna teoria dos contratos incompletos. A Economia dos Custos de Transa??o (ECT) e a Teoria da Ag?ncia surgem dentro desta evolu??o, sendo bastante utilizadas em estudos associados ao tema. Empiricamente, a An?lise Envolt?ria de Dados (DEA) vem se firmando como ferramenta adequada para an?lises de efici?ncia. Embora a ECT argumente que ativos espec?ficos devam ser internalizados, estudos recentes fora do mainstream da teoria mostram que, muitas vezes, as firmas podem decidir, por motivos diversos, contrat?-los no mercado. As pesquisas sobre custos de transa??o deparam-se, com a indisponibilidade de informa??es e com dificuldades metodol?gicas para medi??o de suas vari?veis cr?ticas. Existe, ainda, a necessidade de aprofundamento metodol?gico. O referencial te?rico contempla trabalhos cl?ssicos da ECT e da Teoria da Ag?ncia, mas tamb?m trabalhos mais recentes, fora do mainstream da ECT, que alertam para a exist?ncia de estrat?gias no uso de ativos espec?ficos n?o necessariamente alinhadas com as ideias cl?ssicas da ECT. A ind?stria petrol?fera brasileira ? o foco da tese, que teve como objetivo avaliar a efici?ncia dos contratos de servi?os de elevada especificidade terceirizados pela Petrobras. Para tanto, foram feitas a categoriza??o dos servi?os terceirizados quanto ? especificidade e a descri??o dos servi?os de mais elevada especificidade. Na sequ?ncia, foi verificada a exist?ncia de rela??o entre a especificidade dos servi?os e uma s?rie de vari?veis, encontrando-se resultados divergentes do que prega o mainstream da ECT. Em seguida, foi elaborado um modelo DEA para an?lise de efici?ncia na utiliza??o de servi?os de sondas de perfura??o terrestres, identificado entre os de mais elevada especificidade. O passo seguinte foi a aplica??o do modelo para medi??o da efici?ncia dos contratos de sondas. Por fim, foi verificada a exist?ncia de rela??o entre a efici?ncia dos contratos e uma s?rie de vari?veis encontrando-se, mais uma vez, resultados n?o condizentes com o mainstream da teoria. No tocante ? an?lise de efici?ncia dos contratos de sonda, o modelo elaborado ? compat?vel com o que se encontra em produ??es acad?micas sobre efici?ncia de sondas. Os resultados quanto ? efici?ncia mostram um largo espectro de escores, com efici?ncias que variam de 31,79% a 100%, sendo baixa a efici?ncia m?dia da amostra. H? conson?ncia entre os resultados do modelo e as pr?ticas adotadas pela Petrobras. Os resultados refor?am a posi??o da DEA como ferramenta importante nos estudos de efici?ncia, com possibilidade de uso para an?lise de outros tipos de contratos. Em termos de achados te?ricos, os resultados refor?am os argumentos de que existem situa??es em que as estrat?gias das organiza??es, no que se referem ? utiliza??o de ativos e servi?os de elevada especificidade, n?o seguem necessariamente o que ? preconizado pelo mainstream da ECT

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Oliveira, Ricardo Miguel de. "Craqueamento termocatal?tico de ?leo de girassol na presen?a da peneira molecular SAPO-5." Universidade Federal do Rio Grande do Norte, 2011. http://repositorio.ufrn.br:8080/jspui/handle/123456789/17637.

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Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
The catalytic cracking of triglycerides presents itself as a possible alternative to the production of biofuels with low emission of pollutants. In this work were synthesized the SAPO-5, the catalysts for the cracking reaction of soybean oil is presented. The solids were powder X-ray diffraction (XRD), thermogravimetric analysis (TG/DTG) and infrared spectroscopy (FTIR). The analyses indicated that the synthesis method has employed to obtain materials with high surface area and high acid. The soybean oil thermal and thermal catalytic cracking, realized from the room temperature to 450 ?C in a simple distillation system, has allowed obtaining two liquid fractions, each consisting of two phases, one aqueous and another organic, organic liquid (OL). The OL obtained from first fractions has shown high acid index, even in the thermal catalytic process. The products obtained in the cracking of soybean oil were analyzed by distillation, acid number, infra-red spectroscopy, density, viscosity, carbon residue, cetane number determination and characterization. The analysis of the products obtained in the presence and in the absence of the SAPO-5 permitted to conclude that all the solids tested presented catalytic activity in the deoxygenation of final products only at the second step of the cracking process
O craqueamento catal?tico de triacilglicer?deos se apresenta como uma alternativa vi?vel para a produ??o de biocombust?veis com baixa emiss?o de poluentes. Neste trabalho foi sintetizado o SAPO-5, o catalisador foi utilizado na rea??o de craqueamento do ?leo de Girassol. O s?lido foi caracterizado por difra??o de raios -X, an?lise termogravim?trica, espectroscopia no infravermelho. As an?lises indicaram que atrav?s do m?todo de s?ntese empregado foram obtidos materiais com elevada ?rea espec?fica e alta acidez. A partir do craqueamento t?rmico e termocatal?tico do ?leo de girassol, realizado desde a temperatura ambiente at? 450 oC em um sistema de destila??o simples, foram obtidas duas fra??es l?quidas, cada uma contendo duas fases, uma aquosa e outra org?nica. A primeira fra??o do l?quido org?nico obtido apresentou alto ?ndice de acidez, no processo de craqueamento t?rmico. Os produtos obtidos no craqueamento de ?leo de Girassol foram analisados por destila??o, ?ndice de acidez, espectroscopia no infravermelho, densidade, viscosidade e determina??o do ?ndice de cetano. A an?lise dos produtos obtidos na presen?a e na aus?ncia do SAPO-5, sintetizados permitiu concluir que todos os s?lidos testados apresentaram atividade catal?tica para a desoxigena??o dos produtos finais apenas na segunda etapa do processo de craqueamento

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Azevedo, Neto Alu?sio. "An?lise de um queimador infravermelho funcionando com combust?vel h?brido : GLP/Bio-?leo." Universidade Federal do Rio Grande do Norte, 2010. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12935.

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Universidade Federal do Rio Grande do Norte
Biomass is considered the largest renewable energy source that can be used in an environmentally sustainable. From the pyrolysis of biomass is possible to obtain products with higher energy density and better use properties. The liquid resultant of this process is traditionally called bio-oil. The use of infrared burners in industrial applications has many advantages in terms of technical-operational, for example, uniformity in the heat supply in the form of radiation and convection, with a greater control of emissions due to the passage of exhaust gases through a macroporous ceramic bed. This paper presents a commercial infrared burner adapted with an ejector proposed able to burn a hybrid configuration of liquefied petroleum gas (LPG) and bio-oil diluted. The dilution of bio-oil with absolute ethanol aimed to decrease the viscosity of the fluid, and improving the stability and atomization. It was introduced a temperature controller with thermocouple modulating two stages (low heat / high heat), and solenoid valves for fuels supply. The infrared burner has been tested, being the diluted bio-oil atomized, and evaluated its performance by conducting energy balance. The method of thermodynamic analysis to estimate the load was used an aluminum plate located at the exit of combustion gases and the distribution of temperatures measured by thermocouples. The dilution reduced the viscosity of the bio-oil in 75.4% and increased by 11% the lower heating value (LHV) of the same, providing a stable combustion to the burner through the atomizing with compressed air and burns combined with LPG. Injecting the hybrid fuel there was increase in the heat transfer from the plate to the environment in 21.6% and gain useful benefit of 26.7%, due to the improved in the efficiency of the 1st Law of Thermodynamics of infrared burner
A biomassa ? considerada a maior fonte renov?vel de energia, podendo ser usada de forma ambientalmente sustent?vel. A partir da pir?lise da biomassa ? poss?vel a obten??o de produtos com maior densidade energ?tica e propriedades de uso melhores. O l?quido resultante do seu processo ? tradicionalmente chamado de bio-?leo. A utiliza??o de queimadores infravermelhos em aplica??es industriais apresenta muitas vantagens do ponto de vista t?cnico-operacional, como por exemplo, homogeneidade no fornecimento de calor, na forma de radia??o e convec??o, apresentando um maior controle das emiss?es devido ? passagem dos gases de exaust?o atrav?s de um leito cer?mico macroporoso. O presente trabalho apresenta um queimador infravermelho comercial adaptado com um ejetor proposto capaz de queimar numa configura??o h?brida de g?s liquefeito de petr?leo (GLP) e bio-?leo dilu?do. A dilui??o do bio-?leo com ?lcool et?lico absoluto teve como principal objetivo diminuir a viscosidade do fluido, e melhorar a estabilidade e a atomiza??o. Foi introduzido um controlador de temperatura com termopar modulando dois est?gios (fogo baixo/alto), e eletrov?lvulas para alimenta??o dos combust?veis. O queimador infravermelho foi submetido a testes e ensaios, sendo atomizado o bio-?leo dilu?do, e avaliado o seu desempenho mediante a realiza??o de balan?o de energia. Como m?todo de an?lise termodin?mica para estimativa de carga foi utilizado uma placa de alum?nio localizada na sa?da dos gases de combust?o, sendo a distribui??o de temperaturas medida por termopares. A dilui??o reduziu a viscosidade do bio-?leo em 75,4% e aumentou em 11% o poder calor?fico inferior do mesmo, propiciando ao queimador uma combust?o est?vel atrav?s da atomiza??o com o ar comprimido e queima conjunta com GLP. Injetando o combust?vel h?brido houve aumento na transfer?ncia de calor da placa para o meio ambiente em 21,6% e ganho energ?tico ?til de 26,7%, em fun??o da melhora na efici?ncia da 1? Lei da Termodin?mica do queimador infravermelho

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Faria, Fatima Regina Dutra. "Desenvolvimento de metodologias anal?ticas alternativas por cromatografia gasosa para an?lise de biodiesel." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/13036.

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Since the beginning of the National Program for Production and Use of Biodiesel in Brazil, in 2004, different raw materials were evaluated for biodiesel production, trying to combine the agricultural diversity of the country to the desire to reduce production coasts. To determine the chemical composition of biodiesel produced from common vegetables oils, international methods have been used widely in Brazil. However, for analyzing biodiesel samples produced from some alternative raw materials analytical problems have been detected. That was the case of biodiesel from castor oil. Due the need to overcome these problems, new methodologies were developed using different chromatographic columns, standards and quantitative methods. The priority was simplifying the equipment configuration, realizing faster analyses, reducing the costs and facilitating the routine of biodiesel research and production laboratories. For quantifying free glycerin, the ethylene glycol was used in instead of 1,2,4-butanetriol, without loss of quality results. The ethylene glycol is a cheaper and easier standard. For methanol analyses the headspace was not used and the cost of the equipment used was lower. A detailed determination of the esters helped the deeper knowledge of the biodiesel composition. The report of the experiments and conclusions of the research that resulted in the development of alternative methods for quality control of the composition of the biodiesel produced in Brazil, a country with considerable variability of species in agriculture, are the goals of this thesis and are reported in the following pages
No Brasil, desde o in?cio do Programa Nacional de Produ??o e Uso do Biodiesel, em 2004, diversas mat?rias primas foram avaliadas para a sua produ??o, tentando aliar a diversidade agr?cola do pa?s ao desejo de diminuir os custos de produ??o. Para determinar a composi??o qu?mica de amostras de biodiesel produzidas a partir dos ?leos mais comuns, os m?todos internacionais t?m sido largamente utilizados no Brasil. Por?m, para an?lises de biodiesel produzido a partir de algumas mat?rias primas alternativas, alguns problemas anal?ticos foram detectados. Esse foi o caso do biodiesel de mamona. Devido ? necessidade de contornar esses problemas, novas metodologias foram desenvolvidas, utilizando colunas cromatogr?ficas, padr?es e diferentes m?todos para quantifica??o, privilegiando a sempre simplifica??o dos equipamentos, a realiza??o de an?lises mais r?pidas, diminuindo os custos e facilitando a rotina dos laborat?rios de pesquisas e de produ??o do biodiesel. No caso das an?lises para quantifica??o da glicerina livre, o etilenoglicol, padr?o muito mais barato e de f?cil aquisi??o, foi utilizado no lugar do 1,2,4-butanotriol, sem perda da qualidade dos resultados. Nas an?lises do metanol a n?o utiliza??o do headspace, diminuiu os custos do equipamento utilizado. A determina??o detalhada dos ?steres presentes ajudou o conhecimento mais profundo da composi??o de amostras de biodiesel provenientes de mat?rias primas alternativas. O relato dos experimentos e as conclus?es das pesquisas que resultaram no desenvolvimento de metodologias alternativas para controle de qualidade da composi??o do biodiesel produzido no Brasil, pa?s com enorme variabilidade de esp?cies na agricultura, s?o os objetivos dessa tese e est?o relatados nas p?ginas seguintes

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Galv?o, Edney Rafael Viana Pinheiro. "An?lise param?trica da inje??o de vapor e solvente em reservat?rios de ?leo pesado." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/13020.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
A significant fraction of the hydrocarbon reserves in the world is formed by heavy oils. From the thermal methods used to recovery these resources, Steamflooding has been one of the main economically viable alternatives. In Brazil, this technology is widely used by Petrobras in Northeast fields. Latent heat carried by steam heats the oil in the reservoir, reducing its viscosity and facilitating the production. In the last years, an alternative more and more used by the oil industry to increase the efficiency of this mechanism has been the addition of solvents. When co-injected with steam, the vaporized solvent condenses in the cooler regions of the reservoir and mixes with the oil, creating a low viscosity zone between the steam and the heavy oil. The mobility of the displaced fluid is then improved, resulting in an increase of oil recovery. To better understand this improved oil recovery method and investigate its applicability in reservoirs with properties similar to those found in Potiguar Basin, a numerical study was done to analyze the influence of some operational parameters (steam injection rate, injected solvent volume and solvent type) on oil recovery. Simulations were performed in STARS ("Steam, Thermal, and Advanced Processes Reservoir Simulator"), a CMG ("Computer Modelling Group") program, version 2009.10. It was found that solvents addition to the injected steam not only anticipated the heated oil bank arrival to the producer well, but also increased the oil recovery. Lower cold water equivalent volumes were required to achieve the same oil recoveries from the models that injected only steam. Furthermore, much of the injected solvent was produced with the oil from the reservoir
Uma por??o significativa das reservas de hidrocarbonetos atualmente existentes no mundo ? formada por ?leos pesados. Dentre os m?todos t?rmicos utilizados para a recupera??o desse tipo de recurso, a Inje??o Cont?nua de Vapor tem se constitu?do como uma das principais alternativas economicamente vi?veis. No Brasil, essa tecnologia ? largamente utilizada pela Petrobras em campos localizados na regi?o Nordeste. O calor latente transportado pelo vapor aquece o ?leo do reservat?rio, reduzindo sua viscosidade e facilitando a produ??o. Nos ?ltimos anos, uma alternativa cada vez mais utilizada pela ind?stria para aumentar a efici?ncia desse mecanismo tem sido a adi??o de solventes. Quando coinjetado com o vapor, o solvente vaporizado se condensa nas regi?es menos aquecidas do reservat?rio e mistura-se ao ?leo, criando uma zona de baixa viscosidade entre o vapor e o ?leo pesado. A mobilidade do fluido deslocado ? ent?o melhorada, implicando num aumento da fra??o recuperada. Para melhor compreender esse mecanismo de recupera??o avan?ada e investigar a sua aplicabilidade em reservat?rios com caracter?sticas semelhantes aos encontrados na Bacia Potiguar, foi realizado um estudo num?rico, onde se verificou a influ?ncia de alguns par?metros operacionais (vaz?o de inje??o de vapor, volume de solvente injetado e tipo de solvente) sobre a recupera??o de ?leo. As simula??es foram realizadas no m?dulo STARS ( Steam, Thermal, and Advanced Processes Reservoir Simulator ) do programa da CMG ( Computer Modelling Group ), vers?o 2009.10. Verificou-se que a adi??o de solventes ao vapor injetado n?o s? antecipou a chegada do banco de ?leo aquecido ao po?o produtor como tamb?m incrementou a recupera??o de ?leo. Menores volumes de ?gua fria equivalente foram requeridos para se obter as mesmas fra??es recuperadas dos modelos que s? injetaram vapor. Al?m disso, boa parte do solvente injetado foi produzido juntamente com o ?leo do reservat?rio

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Feij?, Julianne Holder da Camara Silva. "A quest?o do petr?leo em terras ind?genas: uma an?lise constitucional ? luz do desenvolvimento sustent?vel." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/13939.

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Recognizing the need to preserve a national ethnic minority, the Constitution, inspired by the pluralistic values of the Constitutional Law State, stipulated a series of rights and guarantees for the conservation of indigenous cultural singularity, disciplining in article 231 the Indians right to maintain their social organization, customs, languages, beliefs and traditions, as well as safeguarding the rights to the lands they traditionally occupy, and the exclusive use of the wealth existing in them, premise of ensuring their physical and cultural continuity, breaking decisively with the paradigm the assimilation of the Indian national civilization. However, despite the Indian policy of ethnic and cultural preservation, the Constitution allowed the exploitation of minerals in aboriginal territory, incorporated herein hydrocarbons, provided they meet certain predetermined requirements, leaving it to the legislature the discipline of ordinary matter. However, this law has not yet been published, with some projects in the National Congress, leaving thus precluding the indigenous subsurface oil exploration until the enactment of enabling legislation. Meanwhile, this paper carries out an integrated analysis of the constitutional protection of ethnic and cultural uniqueness of indigenous peoples, Convention N? 169 of the International Labour Organization and the bill presented by Deputy Eduardo Valverde, in an attempt to consolidate sustainable development practices in the sector, through developing a system of social and environmental responsible oil exploration, aligning with national energy needs to maintain a balanced environment and preservation of socio-cultural organization of a minority so weakened and beaten over five centuries of domination
Reconhecendo a necessidade de preservar uma minoria ?tnica nacional, a Constitui??o Federal, inspirada nos valores pluralistas do Estado Constitucional de Direito, estipulou uma s?rie de direitos e garantias em prol da conserva??o da singularidade cultural ind?gena, perfilhando em seu artigo 231 o direito dos ?ndios em manter sua organiza??o social, seus costumes, l?nguas, cren?as e tradi??es, al?m de resguardar os direitos origin?rios sobre as terras que tradicionalmente ocupam e o usufruto exclusivo das riquezas nelas existentes, premissa inafast?vel da garantia de sua continuidade f?sica e cultural, rompendo definitivamente com o paradigma da assimila??o do ?ndio ? civiliza??o nacional. Entretanto, apesar da pol?tica indigenista de preserva??o ?tnica e cultural, a pr?pria Constitui??o possibilitou a explora??o de min?rios em territ?rio abor?gene, aqui inclu?do os hidrocarbonetos, desde que observadas algumas exig?ncias preestabelecidas, ficando a cargo do legislador ordin?rio a disciplina da mat?ria. No entanto, esta lei ainda n?o foi editada, existindo alguns projetos em tramita??o no Congresso Nacional, restando, por conseguinte, inviabilizada a explora??o petrol?fera em subsolo ind?gena at? a promulga??o da legisla??o competente. Neste ?nterim, o presente trabalho realiza uma an?lise integrada entre as disposi??es constitucionais de tutela ? singularidade ?tnica e cultural ind?gena, a Conven??o n? 169 da Organiza??o Internacional do Trabalho (OIT) e o projeto de lei apresentado pelo Deputado Eduardo Valverde, na tentativa de consolidar o desenvolvimento sustent?vel nas pr?ticas do setor, atrav?s da estrutura??o de um regime socioambiental respons?vel de explora??o petrol?fera, compatibilizando a necessidade energ?tica nacional com a manuten??o do meio ambiente equilibrado e preserva??o da organiza??o sociocultural de uma minoria t?o fragilizada e agredida ao longo de cinco s?culos de domina??o

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Fontes, Grazielly dos Anjos. "Novas fronteiras petrol?feras no Brasil : uma an?lise da necessidade de nova regulamenta??o da ?rea do pr?-sal sob a ?tica constitucional." Universidade Federal do Rio Grande do Norte, 2010. http://repositorio.ufrn.br:8080/jspui/handle/123456789/13911.

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The Oil industry in Brazil has gone through several stages during the economical, political and social historical process. However, the significative changes have happened in the last fifteen years, due to market opening arising from the relaxation of the state monopoly over the Oil deposits and its derivatives. The edition of the Constitutional Amendment #9, changing the first paragraph of the 177th item of the Federal Constitution, marked the end of a stiffness about the monopoly that the Brazilian state kept in relation to the exploration and research of Oil and Gas. The economical order was fundamental to actualize the idea contained in the #9 Amendment, since its contents has the power to set up measures to be adopted by public power in order to organize the economical relations from a social viewpoint. The new brazilian Oil scenery, called pre-salt, presents itself in a way to amaze the economical markets, in addition to creating a new perspective to the social sector. This work will identify, in this new scenario, the need for change in the legal system. Nevertheless, this subject must not be treated in a thoughtless way: being an exhaustible good, we shall not forget that the future generations also must benefit from the exploration of natural resources recently discovered. The settlement of a new regulatory mark, including the change in the concession contract model to production and sharing is one of the suggested solutions as a bill in the National Congress, in an attempt to ensure the sovereignty of the nation. The constitutionality of a new regulatory mark is questioned, starting from an analysis of the state monopoly, grounding the comprehnsions in the brazilian constitutions, the relevance of the creation of Petrobras for self-assertion of the state about the monopoly of Oil and derivatives, and its posture after the Constitutional Amendment n? 9 (1995), when a company stops having control of the state monopoly, beginning to compete in a fairly way with other companies. The market opening and private initiative are emphasized from the viewpoint of the Constitutional Principles of the Economical and Social Order. The relaxation of the monopoly regarding the exploratory activity in the Federal Constitution doesn't deprive from the Union the ownerships of underground goods, enabling to this federal entity to contract, directly or by concession of exploration of goods, to state-owned or private companies. The existing oil in the pre-salt layer transforms the scenario from very high risk to low risk, which gives the Union the possibility of defining another way of exploring this resources in the best interests of the Public Administration
A ind?stria do petr?leo no Brasil passou por v?rias etapas durante o processo hist?rico econ?mico, pol?tico e social. Todavia, suas significativas mudan?as ocorreram nos ?ltimos quinze anos, atrav?s da abertura do mercado decorrente da flexibiliza??o do monop?lio estatal sobre as jazidas de petr?leo e seus derivados. A edi??o da Emenda Constitucional n? 9, alterando o par?grafo 1?, do art. 177 da Constitui??o Federal, caracterizou o fim de uma rigidez quanto ao monop?lio que o Estado brasileiro mantinha em rela??o ? pesquisa e explora??o de petr?leo e g?s. A ordem econ?mica foi fundamental para efetivar a id?ia contida na Emenda n? 9, visto que seu conte?do tem o cond?o de estabelecer medidas a serem adotadas pelo poder p?blico a fim de organizar as rela??es econ?micas, sob o vi?s social. O novo cen?rio petrol?fero brasileiro, denominado pr?-sal, apresenta-se de forma a surpreender os mercados econ?micos, al?m de criar uma nova perspectiva para o setor social. O presente trabalho identificar? no novo cen?rio a necessidade de mudan?a do regime jur?dico, todavia, esse assunto n?o pode ser tratado de forma imediatista: como se trata de um bem esgot?vel n?o se deve esquecer que as gera??es futuras tamb?m precisam beneficiar-se da explora??o dos recursos naturais rec?m-descobertos. O estabelecimento de um novo marco regulat?rio, incluindo a mudan?a do modelo de contrato concess?o para produ??o e partilha ? uma das solu??es propostas a n?vel de projeto de lei no Congresso Nacional na tentativa de garantir a soberania da na??o. Questiona-se a constitucionalidade de um novo marco regulat?rio, partindo-se da an?lise do monop?lio estatal, resgatando a compreens?o nas constitui??es brasileiras, a relev?ncia da cria??o da Petrobras para auto-afirma??o do Estado quanto ao monop?lio de petr?leo e derivados, e sua postura ap?s a Emenda Constitucional n? 9 de 1995 quando a empresa deixa de ter o controle do monop?lio estatal, passando a concorrer de forma igualit?ria com outras empresas. Ressalva-se a abertura do mercado e a iniciativa privada sob ?tica dos Princ?pios Constitucionais da Ordem Econ?mica e Social. A flexibiliza??o do monop?lio quanto a atividade explorat?ria na Constitui??o Federal n?o retira da Uni?o a propriedade dos bens do subsolo, possibilitando a este ente federal a contrata??o direta ou atrav?s de concess?o da explora??o do bem a empresas estatais ou privada. O petr?leo existente na camada pr?-sal, transforma um cen?rio de alt?ssimo risco em baixo risco, o que confere a Uni?o a possibilidade de determina??o de outra forma de explorar esses recursos de forma a fazer vale os interesses prim?rio da Administra??o P?blica

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Azevedo, Fabiano Medeiros de. "Proposta de algoritmo para detec??o de vazamentos em oleodutos utilizando an?lise freq?encial de sinais de press?o." Universidade Federal do Rio Grande do Norte, 2009. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15296.

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Petr?leo Brasileiro SA - PETROBRAS
Pipeline leak detection is a matter of great interest for companies who transport petroleum and its derivatives, in face of rising exigencies of environmental policies in industrialized and industrializing countries. However, existing technologies are not yet fully consolidated and many studies have been accomplished in order to achieve better levels of sensitivity and reliability for pipeline leak detection in a wide range of flowing conditions. In this sense, this study presents the results obtained from frequency spectrum analysis of pressure signals from pipelines in several flowing conditions like normal flowing, leakages, pump switching, etc. The results show that is possible to distinguish between the frequency spectra of those different flowing conditions, allowing recognition and announce of liquid pipeline leakages from pressure monitoring. Based upon these results, a pipeline leak detection algorithm employing frequency analysis of pressure signals is proposed, along with a methodology for its tuning and calibration. The proposed algorithm and its tuning methodology are evaluated with data obtained from real leakages accomplished in pipelines transferring crude oil and water, in order to evaluate its sensitivity, reliability and applicability to different flowing conditions
A detec??o de vazamentos em dutos ? assunto de grande interesse para empresas que realizam o transporte de petr?leo e seus derivados, tendo em vista o crescente rigor da legisla??o ambiental nos pa?ses industrializados e em processo de industrializa??o. No entanto, as tecnologias existentes hoje ainda n?o est?o plenamente consolidadas e estudos v?m sendo realizados com vistas a atingir maiores n?veis de sensibilidade e confiabilidade para a detec??o de vazamentos em uma ampla variedade de regimes de escoamento. Neste sentido, este estudo apresenta os resultados obtidos com a an?lise do espectro de freq??ncia de sinais de press?o de oleodutos em diversas situa??es de escoamento, tais como escoamento normal, vazamentos, partida e parada de bombas, etc. Os resultados indicam que ? poss?vel diferenciar o espectro freq?encial dessas diferentes condi??es de escoamento, o que permite reconhecer e indicar a ocorr?ncia de vazamentos em dutos transportando fluidos l?quidos a partir da monitora??o de sua press?o. Com base nestes resultados, s?o propostos um algoritmo para detec??o de vazamentos em dutos utilizando a an?lise freq?encial de sinais de press?o e uma metodologia para sintonia e calibra??o deste algoritmo. O algoritmo e a metodologia de sintonia propostos s?o avaliados com dados obtidos a partir de vazamentos reais provocados em dutos transferindo petr?leo e ?gua, a fim de avaliar sua sensibilidade, confiabilidade e aplicabilidade para diferentes condi??es de escoamento

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Correia, Iara Michelle Silva. "Extra??o e pir?lise do ?leo de girassol (Helianthus annus l.) visando a produ??o de biocombust?veis." Universidade Federal do Rio Grande do Norte, 2009. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15782.

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Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
Nowadays, the growing environmental worry leads research the focus the application of alternative materials from renewable resources on the industrial process. The most common vegetable oil extractant using around the world is the hexane, a petroleum derived, toxic and flammable. Based on this fact, the goal of this work was to test vegetable oil extractions from sunflower seeds cultivated on the Rio Grande do Norte State using two extraction process, the mechanical expelling and solvent extraction, this one using hexane and ethanol as a alternative solvent. The solvent extractions were carried out in the Soxhlet extractor in three different extraction times (4, 6, and 8 hours). The effect of solvent and extraction time was evaluated. The mechanical extraction was carried out in a expeller and the sunflower oil obtained was characterized by its physical-chemical properties and compared with sunflower refinery oil. Furthermore this work also explored the pyrolysis reaction carried out by thermogravimetry measurement as alternative route to obtain biofuel. For this purpose the oil samples were heated to ambient temperature until 900?C in heating rate of 5, 10, 20?C min-1 with the objective evaluated the kinetics parameters such activation energy and isoconversion. The TG/DTG curves show the thermal profile decomposition of triglycerides. The curves also showed that antioxidant presents on the refinery oil not influence on the thermal stability of sunflower oil. The total yield of the extraction s process with hexane and ethanol solvent were compared, and the results indicated that the extraction with ethanol were more efficient. The pyrolysis reaction results indicated that the use of unpurified oil required less energy to obtain the bio-oil
Atualmente, o aumento da preocupa??o com o meio ambiente, incentiva as pesquisas que buscam a aplica??o de materiais alternativos provenientes de fontes renov?veis em processos industriais. O extratante de ?leo vegetal mais utilizado no mundo ? o hexano, um derivado de petr?leo t?xico e inflam?vel. Considerando este fato, o presente trabalho teve por objetivo realizar extra??es do ?leo das sementes de girassol cultivadas no Estado do Rio Grande do Norte usando dois processos de extra??o, a extra??o mec?nica e a extra??o com solventes, utilizando hexano e etanol como solvente alternativo. As extra??es com solvente foram realizadas em um extrator Soxhlet utilizando tr?s tempos de extra??o (4, 6 e 8 horas). O efeito do solvente no rendimento da extra??o foi avaliado. O ?leo de girassol obtido da extra??o mec?nica foi caracterizado em rela??o as suas propriedades fisico-qu?micas e comparadas com as propriedades do ?leo de girassol refinado. Al?m disso, o presente trabalho explora as rea??es de pir?lise do ?leo de girassol como uma rota alternativa para a obten??o de biocombust?veis realizadas em um analisador termogravim?trico. Com essa finalidade as amostras de ?leo foram aquecidas da temperatura ambiente at? 900?C em raz?es de aquecimento de 5, 10, 20 ?C min-1 com o objetivo de avaliar os par?metros cin?ticos tais como energia de ativa??o e isoconvers?o. As curvas TG/DTG mostram o perfil t?rmico de decomposi??o dos triglicer?deos. As curvas mostraram tamb?m que o antioxidante presente no ?leo refinado comercial, n?o influencia a estabilidade t?rmica do ?leo de girassol. O rendimento dos processos de extra??o com hexano e etanol foi comparado e os resultados indicaram que a extra??o com etanol foi mais eficiente. Os resultados das rea??es de pir?lise indicaram que o uso do ?leo bruto requer menos energia para a obten??o de biocombust?veis que o ?leo refinado

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Mendes, D?bora Cosme Pereira. "Metodologias estat?sticas aplicadas a dados de an?lises qu?micas da ?gua produzida em um campo maduro de petr?leo." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12972.

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Produced water is characterized as one of the most common wastes generated during exploration and production of oil. This work aims to develop methodologies based on comparative statistical processes of hydrogeochemical analysis of production zones in order to minimize types of high-cost interventions to perform identification test fluids - TIF. For the study, 27 samples were collected from five different production zones were measured a total of 50 chemical species. After the chemical analysis was applied the statistical data, using the R Statistical Software, version 2.11.1. Statistical analysis was performed in three steps. In the first stage, the objective was to investigate the behavior of chemical species under study in each area of production through the descriptive graphical analysis. The second step was to identify a function that classify production zones from each sample, using discriminant analysis. In the training stage, the rate of correct classification function of discriminant analysis was 85.19%. The next stage of processing of the data used for Principal Component Analysis, by reducing the number of variables obtained from the linear combination of chemical species, try to improve the discriminant function obtained in the second stage and increase the discrimination power of the data, but the result was not satisfactory. In Profile Analysis curves were obtained for each production area, based on the characteristics of the chemical species present in each zone. With this study it was possible to develop a method using hydrochemistry and statistical analysis that can be used to distinguish the water produced in mature fields of oil, so that it is possible to identify the zone of production that is contributing to the excessive elevation of the water volume.
A ?gua produzida caracteriza-se como um dos res?duos mais comuns gerados durante as fases de explora??o e produ??o de petr?leo. Este trabalho tem como objetivo desenvolver metodologias baseadas em processos estat?stico-comparativos de an?lises hidrogeoqu?micas de zonas de produ??o com o objetivo de minimizar tipos de interven??es de altos custos para realiza??o de teste de identifica??o de fluidos TIF. Para o estudo, foram coletadas 27 amostras de cinco zonas de produ??o diferentes e foram medidos um total de 50 esp?cies qu?micas. Ap?s as an?lises qu?micas foi aplicado o tratamento estat?stico aos dados, utilizando o Software Estat?stico R, vers?o 2.11.1. O tratamento estat?stico foi realizado em tr?s etapas. Na primeira etapa, o objetivo foi verificar o comportamento das esp?cies qu?micas em estudo em cada zona de produ??o atrav?s da an?lise gr?fica descritiva. A segunda etapa consistiu em identificar uma fun??o que classificasse as zonas de produ??o de cada amostra, utilizando An?lise Discriminante. Na etapa de treinamento, a taxa de acerto de classifica??o da fun??o da an?lise discriminante foi de 85,19%. A etapa seguinte do tratamento estat?stico dos dados utilizou An?lise de Componentes Principais para, atrav?s da redu??o do n?mero de vari?veis obtidas a partir da combina??o linear das esp?cies qu?micas, tentar melhorar a fun??o discriminante obtida na segunda etapa e aumentar o poder de discrimina??o dos dados, por?m o resultado n?o foi satisfat?rio. Na An?lise de Perfis foram obtidas curvas para cada zona de produ??o, baseadas nas caracter?sticas das esp?cies qu?micas presentes em cada zona. Com este trabalho foi poss?vel desenvolver uma metodologia utilizando a hidroqu?mica e a an?lise estat?stica que pode ser utilizada para distinguir a ?gua produzida em campos maduros de petr?leo, de forma que seja poss?vel identificar a zona de produ??o que est? contribuindo para a eleva??o excessiva do volume de ?gua.

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Lima, Cicero de Souza. "Pir?lise de borras oleosas de petroleo utilizando nanomateriais." Universidade Federal do Rio Grande do Norte, 2014. http://repositorio.ufrn.br:8080/jspui/handle/123456789/13030.

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The oily sludge is a complex mix of hydrocarbons, organic impurities, inorganic and water. One of the major problems currently found in petroleum industry is management (packaging, storage, transport and fate) of waste. The nanomaterials (catalysts) mesoporous and microporous are considered promising for refining and adsorbents process for environment protection. The aim of this work was to study the oily sludge from primary processing (raw and treated) and vacuum residue, with application of thermal analyses technique (pyrolysis), thermal and catalytic pyrolysis with nanomaterials, aiming at production petroleum derived. The sludge and vacuum residue were analyzed using a soxhlet extraction system, elemental analysis, thin layer chromatography, thermogravimetry and pyrolysis coupled in gas chromatography/mass spectrometry (Py GC MS). The catalysts AlMCM-41, AlSBA-15.1 e AlSBA-15.2 were synthesized with molar ratio silicon aluminum of 50 (Si/Al = 50), using tetraethylorthosilicante as source of silicon and pseudobuhemita (AlOOH) as source of aluminum. The analyzes of the catalysts indicate that materials showed hexagonal structure and surface area (783,6 m2/g for AlMCM-41, 600 m2/g for AlSBA-15.1, 377 m2/g for AlSBA-15.2). The extracted oily sludge showed a range 65 to 95% for organic components (oil), 5 to 35% for inorganic components (salts and oxides) and compositions different of derivatives. The AlSBA-15 catalysts showed better performance in analyzes for production petroleum derived, 20% increase in production of kerosene and light gas oil. The energy potential of sludge was high and it can be used as fuel in other cargo processed in refinery
A borra oleosa (BO) de petr?leo ? uma mistura complexa de hidrocarbonetos, impurezas org?nicas, inorg?nicas e ?gua. Um dos grandes problemas encontrados atualmente na ind?stria de petr?leo ? o gerenciamento (acondicionamento, armazenamento, transporte e destino) de res?duos. Os nanomateriais (catalisadores) mesoporosos e microporosos s?o considerados promissores em processos de refino de petr?leo e como adsorventes para prote??o ambiental. O objetivo deste trabalho foi estudar a BO de petr?leo oriunda do processamento prim?rio (bruta e tratada) e res?duo de v?cuo, com aplica??o de an?lise termogravim?trica, t?cnica de pir?lise t?rmica e catal?tica com nanomateriais, visando a produ??o de derivado de petr?leo. As borras extra?das em um equipamento soxhlet foram analisadas por an?lise elementar, cromatografia em camada fina, termogravimetria (TG) e pir?lise acoplado a um cromatogr?fico gasoso/espectro de massa (Py-GC/MS). Os catalisadores AlMCM-41 e AlSBA-15 foram sintetizados com uma raz?o molar de s?licio/alum?nio de 50 (Si/Al = 50), usando tetraetilortossilicato (TEOS) como fonte de sil?cio e pseudobuhemita (AlOOH) como a fonte de alum?nio. Os catalisadores indicam que os materiais apresentaram estrutura hexagonal, ?rea espec?fica de 783,6 m2/g para o AlMCM-41, 600 m2/g para o AlSBA-15.1 e 377 m2/g para o AlSBA-15.2). A BO extra?da apresentou de 65 a 95% de componentes org?nicos (?leo), de 5 a 35% de componentes inorg?nicos (sais e ?xidos) e diferentes composi??es dos derivados. Os catalisadores tipo AlSBA-15 apresentaram melhor desempenho na obten??o dos derivados de petr?leo, aumentando em 20% a produ??o de querosene e gas?leo leve. O potencial energ?tico da BO foi elevado, pois ela pode ser utilizada como combust?vel e processada com outras cargas pesadas do petr?leo para a produ??o de diferentes derivados de petr?leo

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Fraz?o, Luciana de Sousa. "Caracteriza??o batim?trica e fisicooceanogr?fica do canal de acesso ao porto de Cabedelo/PB: uma an?lise ambiental ao derrame de ?leo." Universidade Federal do Rio Grande do Norte, 2011. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12946.

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The State of Para?ba is one of the most dynamic states of Brazil, strategically located in the northeast, is notable for the excellent potential for integration of different transportation modes forming the states of Rio Grande do Norte, Pernambuco and Alagoas. The dynamic that occurs with port activity causes changes in the space where it is installed. And the elements of this space are always more than suffering direct or indirect influences as the flow in the port is expanded. Therefore, this region became subject to the accidental spillage of oil, because it presents a heavy traffic of ships of various sizes that can run aground or collide with oil causing accidental events. The study of geomorphological and sedimentological compositions of seafloor becomes important as more is known about the relationships between these parameters and associated fauna, and can identify their preferred habitats. The database background, acoustically collected along the proposed study area, is a wealth of information, which were duly examined, cataloged and made available. Such information can serve as an important tool, providing a geomorphological survey of the sedimentary area studied, and come to subsidize, in a flexible, future decision making. With the study area Port of Cabedelo, Para?ba - Brazil, this research aimed to evaluate the influence of the tidal surface and background in modeling the seabed, including the acquisition of information about the location of submerged rocky bodies and the depth of these bodies may turn out to be natural traps for the trapping of oil in case of leaks, and obtain the relationship between types of bed and the hydrodynamic conditions present in the region. In this context, for this study were collected bathymetric data (depth) and physical oceanographic (height of water column, water temperature, intensity and direction of currents, waves and turbidity), meteorological (rainfall, air temperature, humidity, winds and barometric pressure) of the access channel to the Port of Cabedelo / PB and its basin evolution (where the cruise ships dock), and includes tools of remote sensing (Landsat 7 ETM +, 2001), so that images and the results are integrated into Geographic Information Systems and used in the elaboration of measures aimed at environmental protection areas under the influence of this scale facilities, serving as a grant to prepare a contingency plan in case of oil spills in the region. The main findings highlight the techniques of using hydroacoustic data acquisition together bathymetric surveys of high and low frequency. From there, five were prepared in bathymetric pattern of Directorate of Hydrography and Navigation - DHN, with the depth in meters, on a scale of 1:2500 (Channel and Basin Evolution of Access to Port of Cabedelo), where there is a large extent possible beachrocks that hinder the movement of vessels in the port area, which can cause collisions, running aground and leaking oil. From the scatter diagram of the vectors of currents, it can be seen as the tidal stream and undergoes a channeling effect caused by the bidirectional effect of the tide (ebb and flood) in the basin of the Port of Cabedelo evolution in NW-direction SE and the highest speed of the currents occurs at low tide. The characterization weather for the period from 28/02 to 04/07/2010 values was within the expected average for the region of study. The multidisciplinary integration of products (digital maps and remote sensing images), proved to be efficient for the characterization of underwater geomorphological study area, reaching the aim to discriminate and enhance submerged structures, previously not visible in the images
O Estado da Para?ba ? um dos estados mais din?micos do Brasil, estrategicamente localizado na regi?o nordeste, se destaca pelo excelente potencial para integra??o dos diversos modais de transporte formado com os Estados do Rio Grande do Norte, Pernambuco e Alagoas e por abrigar o Porto de Cabedelo. A din?mica que ocorre com a atividade portu?ria provoca mudan?as no espa?o onde ele ? instalado. E os elementos que comp?em esse espa?o passam ent?o a sofrer sempre mais influ?ncias diretas ou indiretas ? medida que o fluxo no porto ? ampliado. Logo, essa regi?o tornou-se pass?vel ao derramamento acidental de ?leo, por apresentar um intenso tr?fego de navios de diversos portes que podem encalhar ou colidir ocasionando eventos acidentais com ?leo. O estudo das composi??es geomorfol?gicas e sedimentol?gicas do fundo oce?nico tornam-se importantes ? medida que se conhece mais a respeito de rela??es entre estes par?metros e a fauna associada, sendo poss?vel identificar seus habitats preferenciais. O banco de dados de fundo, acusticamente coletados ao longo da ?rea do estudo proposto, constitui um grande acervo de informa??es, que foram devidamente analisadas, catalogadas e disponibilizadas. Tais informa??es podem servir como uma importante ferramenta, proporcionando um levantamento geomorfol?gico da ?rea estudada, e vir a subsidiar, de forma ?gil, futuras tomadas de decis?o. Tendo como ?rea de estudo Porto de Cabedelo, Para?ba - Brasil, esta pesquisa objetivou avaliar a influ?ncia das correntes de mar?s superficiais e de fundo na modelagem do leito marinho, incluindo a aquisi??o de informa??es sobre a localiza??o de corpos rochosos submersos e a profundidade desses corpos que podem vir a se tornar armadilhas naturais para o aprisionamento de ?leo em casos de vazamentos, al?m de obter a rela??o entre tipos de leito e as condi??es hidrodin?micas atuais na regi?o. Nesse contexto, para este trabalho, foram coletados dados batim?tricos (profundidade) e f?sico-oceanogr?ficos (altura de coluna d ?gua, temperatura da ?gua, intensidade e dire??o das correntes, ondas e turbidez), meteorol?gicos (precipita??o pluviom?trica, temperatura do ar, umidade do ar, ventos e press?o barom?trica) do canal de acesso ao Porto de Cabedelo/PB e sua bacia de evolu??o (local onde os navios atracam), incluindo ainda ferramentas do Sensoriamento Remoto (imagens Landsat 7 ETM+, 2001), para que as imagens e os resultados obtidos sejam integrados em Sistemas de Informa??o Geogr?fica e utilizados na elabora??o de medidas que visem ? prote??o ambiental de ?reas sob influ?ncia de instala??es desse porte, servindo como subs?dio para elabora??o de um plano de conting?ncia em casos de derrames de ?leo na regi?o. Como principais resultados destacam-se as t?cnicas de aquisi??o de dados hidroac?sticos utilizando em conjunto levantamentos batim?tricos de alta e baixa frequ?ncia. A partir disso, foram elaboradas cinco cartas batim?tricas no padr?o da Diretoria de Hidrografia e Navega??o - DHN, apresentando a profundidade em metros, na escala de 1:2.500 (Bacia de Evolu??o e Canal de Acesso ao Porto de Cabedelo), onde observa-se em grande extens?o poss?veis arenitos praiais que dificultam a movimenta??o das embarca??es na ?rea do porto, podendo provocar colis?es, encalhe e vazamentos de ?leo. A partir do digrama de dispers?o dos vetores de correntes, pode-se observar como a corrente de mar? sofre uma canaliza??o e com sentido bidirecional provocado pelo efeito da mar? (vazante e enchente) na bacia de evolu??o do Porto de Cabedelo, no sentido NW-SE e que a maior velocidade das correntes ocorre na baixa-mar. A caracteriza??o meteorol?gica referente ao per?odo de 28/02 a 04/07/2010 apresentou valores dentro das m?dias esperadas para a regi?o de estudo. A integra??o de produtos multidados (mapas digitais e imagens de sensores remotos), mostrou-se eficiente para a caracteriza??o geomorfol?gica submersa da ?rea estudada, alcan?ando o intuito de discriminar e real?ar estruturas submersas, antes n?o percept?veis nas imagens

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Sena, Caio Patr?cio de Souza. "An?lise qu?mica de produtos de incrusta??o em dutos de petr?leo por espectometria de fluoresc?ncia de raios X." Universidade Federal do Rio Grande do Norte, 2008. http://repositorio.ufrn.br:8080/jspui/handle/123456789/17614.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
The quantitative chemical characterization of the inorganic fraction of scale products is very relevant in studying, monitoring and controlling corrosive processes of oil pipelines. The X-ray fluorescence spectrometry (XRF) is a very versatile analytical technique, which can be used in quantitative analysis in solid samples at low concentrations of the chemical element, in the order of few ppm. A methodology that involves sample preparation diluted in the proportion of 1:7 (one portion of the sample for seven of wax), pressed as pellets was used in the XRF calibration for chemical analysis of scale products from oil pipelines. The calibration involved the preparation of reference samples from mixtures of P.A. reagents, aiming to optimize the time consumed in the steps of sample preparation and analysis of Al, Ba, Ca, Fe, K, Mg, Mn, Na, P, S, Si, Sr and Ti, using the same pressed pellet for trace and major elements analysis
A caracteriza??o qu?mica quantitativa da fra??o inorg?nica de produtos de incrusta??o ? de grande relev?ncia no estudo, monitoramento e controle de processos corrosivos em dutos de petr?leo. A espectrometria por fluoresc?ncia de raios X (EFRX) ? uma t?cnica anal?tica muito vers?til, que pode ser utilizada na obten??o de resultados quantitativos de amostras s?lidas em baixas concentra??es do elemento qu?mico, da ordem de alguns ppm. Uma metodologia de prepara??o de amostras dilu?das na propor??o de 1:7 (uma por??o de amostra para sete de cera), posteriormente prensadas na forma de pastilhas foi utilizada na calibra??o do EFRX para an?lise de produtos de incrusta??o de dutos de petr?leo. O processo de calibra??o envolveu a confec??o de amostras de refer?ncia a partir de misturas de reagentes P.A., onde se buscou a otimiza??o do tempo envolvido nas etapas de prepara??o de amostras e an?lise dos elementos Al, Ba, Ca, Fe, K, Mg, Mn, Na, P, S, Si, Sr e Ti, utilizando-se as mesmas pastilhas para dosagem de elementos tra?os e maiores

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Silva, Francisco Wilton de Freitas. "DFA e an?lise de agrupamento aplicadas a perfis de porosidade neutr?nico em po?os de petr?leo." Universidade Federal do Rio Grande do Norte, 2009. http://repositorio.ufrn.br:8080/jspui/handle/123456789/18534.

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?Peng was the first to work with the Technical DFA (Detrended Fluctuation Analysis), a tool capable of detecting auto-long-range correlation in time series with non-stationary. In this study, the technique of DFA is used to obtain the Hurst exponent (H) profile of the electric neutron porosity of the 52 oil wells in Namorado Field, located in the Campos Basin -Brazil. The purpose is to know if the Hurst exponent can be used to characterize spatial distribution of wells. Thus, we verify that the wells that have close values of H are spatially close together. In this work we used the method of hierarchical clustering and non-hierarchical clustering method (the k-mean method). Then compare the two methods to see which of the two provides the best result. From this, was the parameter ? (index neighborhood) which checks whether a data set generated by the k- average method, or at random, so in fact spatial patterns. High values of ? indicate that the data are aggregated, while low values of ? indicate that the data are scattered (no spatial correlation). Using the Monte Carlo method showed that combined data show a random distribution of ? below the empirical value. So the empirical evidence of H obtained from 52 wells are grouped geographically. By passing the data of standard curves with the results obtained by the k-mean, confirming that it is effective to correlate well in spatial distribution
Peng foi o primeiro a trabalhar com a T?cnica DFA (Detrended Fluctuation Analysis), uma ferramenta capaz de detectar auto-correla??o de longo alcance em s?ries temporais com n?o-estacionaridade. Nesse trabalho, a t?cnica de DFA ? utilizada para obter o expoente de Hurst (H) do perfil el?trico de Porosidade Neutr?nica dos 52 po?os petrol?feros Campo de Namorado, situado na Bacia de Campos ? RJ. A finalidade ? saber se o expoente de Hurst pode ou n?o ser usado para se caracterizar uma distribui??o espacial dos po?os. Assim, queremos verificar se os po?os que apresentam valores pr?ximos de H est?o espacialmente pr?ximos entre si. Neste trabalho foi utilizado o m?todo de agrupamento hier?rquico e o m?todo de agrupamento n?o hier?rquico (m?todo do k-m?dia). Em seguida comparamos os dois m?todos para ver qual dos dois fornece o melhor resultado. A partir disso, foi criado o par?metro (?ndice de vizinhan?a) o qual verifica se um conjunto de dados gerados pelo m?todo km?dia, ou de forma aleat?ria, forma de fato padr?es espaciais. Altos valores de indicam que os dados est?o agregados, enquanto que baixos valores de indicam que os dados est?o espalhados (sem correla??o espacial). Com aux?lio do m?todo de Monte Carlo observou-se que dados agrupados aleatoriamente apresentam uma distribui??o de inferior ao valor emp?rico. Portanto os dados emp?ricos de H obtidos dos 52 po?os est?o agrupados espacialmente. Ao cruzar os dados das curvas de n?vel com os resultados obtidos pelo k-m?dia, confirmam que este ? eficaz para correlacionar po?os em distribui??o espacial

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Ramos, Moacir Bispo. "Desenvolvimento de um sistema para an?lise de integridade estrutural de equipamentos est?ticos baseado em cad vps micro cracks e ultrassom." Universidade Federal do Rio Grande do Norte, 2009. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15609.

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Universidade Federal do Rio Grande do Norte
In general, the designs of equipment takes into account the effects and processes of deterioration it will undergo and arrives at an approximate useful life. However, changes in operational processes and parameters, the action of external agents, the kind of maintenance conducted, the means of monitoring, and natural and accidental occurrences completely modify the desired performance of the equipment. The discontinuities that occur in anisotropic materials often and due to different factors evolve from being subcritical to critical acquiring the status of defect and compromising the physical integrity of the equipment. Increasingly sophisticated technological means of detection, monitoring and assessment of these discontinuities are required to respond ever more rapidly to the requirements of industry. This paper therefore presents a VPS (Virtual Pipe System) computational tool which uses the results of ultrasonic tests on equipment, plotting the discontinuities found in models created in the CAD and CAE systems, and then simulates the behavior of these defects in the structure to give an instantaneous view of the final behavior. This paper also presents an alternative method of conventional ultrasonic testing which correlates the integrity of an overlay (carbon steel and stainless steel attached by welding) and the reflection of ultrasonic waves coming from the interface between the two metals, thus making it possible to identify cracks in the casing and a shift of the overlay
Os projetos de equipamentos em geral j? contemplam os esfor?os e os mecanismos de de processo e de par?metros operacionais, a??o de agentes externos, esp?cie de manuten??o aplicada, forma de acompanhamento, ocorr?ncias naturais e acidentes modificam completamente deteriora??o a que estes est?o submetidos, prevendo aproximadamente sua vida ?til, por?m, mudan?as o comportamento esperado dos equipamentos. As descontinuidades em materiais anisotr?picos muitas vezes e, por diversos fatores, evoluem da condi??o de subcr?ticas para cr?ticas assumindo o status de defeito e comprometendo a integridade f?sica do equipamento. Meios de detec??o, monitora??o e avalia??o dessas descontinuidades, cada vez mais tecnol?gicos, s?o requeridos para responderem de forma mais eficaz ? exig?ncia da ind?stria. Assim, este trabalho apresenta uma ferramenta computacional VPS (Virtual Pipe System) que utiliza o resultado de ensaios de ultrassom em equipamentos plotando essas descontinuidades encontradas em modelos criados em sistemas CAD e CAE e, ainda, simula o comportamento desses defeitos na estrutura possibilitando a visualiza??o instant?nea do comportamento final. Apresenta-se ainda neste trabalho um m?todo alternativo de ensaio ultrass?nico convencional que correlaciona a integridade de um overlay (a?o carbono e a?o inoxid?vel depositado por solda) com as reflex?es de ondas de ultra-som provindas da interface entre os dois metais, possibilitando a identifica??o de trincas no revestimento e de descolamento do overlay

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Medeiros, Suzan Ialy Gomes de. "S?ntese enzim?tica de biosurfactante e sua aplicabilidade na ind?stria do petr?leo." Universidade Federal do Rio Grande do Norte, 2007. http://repositorio.ufrn.br:8080/jspui/handle/123456789/17593.

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Enzymes have been widely used in biosynthesis/transformation of organic compounds in substitution the classic synthetic methods. This work is the first writing in literature of enzymatic synthesis for attainment the biossurfactants, the use glucose sucrose, ricinoleic acid e castor oil as substratum, and as biocatalyst, used immobilized lipase Thermomyces lanuginose, Rhizomucor miehei and the Candida antarctica lipase B; alkaline protease and neutral protease from Bacillus subtillis and yeast Saccharomyces cerevisiaeI. The analysis of HPLC (high performance liquid chromatography) showed that highest conversions were reached of used the alkaline protease from Bacillus subtillis. Laboratory tests, to evaluate the applicability, indicated that the produced biosurfactantes had good stability in presence of salts (NaCl) and temperature (55 e 25?C), they are effective in the reduction of the superficial tension and contac angle, but they have little foaming capacity, when compared with traditional detergents. These results suggest that the prepared surfactants have potential application as wetting agent and perforation fluid stabilizer
Enzimas t?m sido largamente utilizadas em ma??es de compostos org?nicos em substitui??o aos m?todos sint?ticos cl?ssicos. Esta disserta??o de mestrado ? o primeiro relato escrito em literatura de s?ntese enzim?tica para obten??o de biosurfactantes utilizando como substratos glicose, ?cido ricinol?ico e ?leo de mamona, e como biocatalizador, foram empregadas lipases imobilizadas (Thermomyces lanuginosa, Rhizomucor miehei e Candida antarctica B), proteases (Bacillus subtillis alcalina e Bacillus subtillis neutra) e levedura (Saccharomyces cerevisiae). A an?lise por CLAE (cromatografia l?quida de alta efici?ncia) mostrou que maiores convers?es foram alcan?adas pelo uso da Bacillus subtillis alcalina. Testes de laborat?rio, para avaliar sua aplicabilidade, indicaram que os biosurfactantes produzidos apresentam boa estabilidade em presen?a de NaCl e temperaturas de 55 e 25?C, s?o efetivos na redu??o da tens?o superficial e ?ngulo de contato, mas possuem pouca capacidade espumante, quando comparados aos detergentes tradicionais. Estes resultados sugerem que os surfactantes obtidos t?m potencial aplica??o como agente de molhabilidade e estabilizador de fluidos de perfura??o
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Parafita, Jofranya Wendyana Alves. "An?lise param?trica do m?todo de inje??o alternada de ?gua e CO2(WAG) em reservat?rios de petr?leo." Universidade Federal do Rio Grande do Norte, 2014. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12998.

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After the decline of production from natural energy of the reservoir, the methods of enhanced oil recovery, which methods result from the application of special processes such as chemical injection, miscible gases, thermal and others can be applied. The advanced recovery method with alternating - CO2 injection WAG uses the injection of water and gas, normally miscible that will come in contact with the stock oil. In Brazil with the discovery of pre-salt layer that gas gained prominence. The amount of CO2 present in the oil produced in the pre-salt layer, as well as some reservoirs is one of the challenges to be overcome in relation to sustainable production once this gas needs to be processed in some way. Many targets for CO2 are proposed by researchers to describe some alternatives to the use of CO2 gas produced such as enhanced recovery, storage depleted fields, salt caverns storage and marketing of CO2 even in plants. The largest oil discoveries in Brazil have recently been made by Petrobras in the pre -salt layer located between the states of Santa Catarina and Esp?rito Santo, where he met large volumes of light oil with a density of approximately 28 ? API, low acidity and low sulfur content. This oil that has a large amount of dissolved CO2 and thus a pioneering solution for the fate of this gas comes with an advanced recovery. The objective of this research is to analyze which parameters had the greatest influence on the enhanced recovery process. The simulations were performed using the "GEM" module of the Computer Modelling Group, with the aim of studying the advanced recovery method in question. For this work, semi - synthetic models were used with reservoir and fluid data that can be extrapolated to practical situations in the Brazilian Northeast. The results showed the influence of the alternating injection of water and gas on the recovery factor and flow rate of oil production process, when compared to primary recovery and continuous water injection or continuous gas injection
O m?todo de recupera??o avan?ada com inje??o alternada WAG-CO2 utiliza da inje??o de ?gua e g?s, g?s esse normalmente misc?vel que vai entrar em contato com o banco de ?leo. No Brasil com a descoberta da camada pr?-sal esse g?s ganhou destaque. A quantidade de CO2 presente no ?leo produzido na camada pr?-sal, assim como acontece em alguns reservat?rios ? um dos desafios a serem vencidos com rela??o ? produ??o sustent?vel uma vez que esse g?s precisa ser processado de alguma maneira. Muitos os destinos para o CO2 s?o propostos por estudiosos, que descrevem algumas alternativas para uso do g?s CO2 produzido, tais como, recupera??o avan?ada, armazenamento em campos depletados, armazenamento em cavernas de sal e ainda comercializa??o do CO2 em plantas. As maiores descobertas de petr?leo, no Brasil, foram feitas recentemente pela Petrobras na camada pr?-sal localizada entre os estados de Santa Catarina e Esp?rito Santo, onde se encontrou grandes volumes de ?leo leve com uma densidade em torno de 28? API, baixa acidez e baixo teor de enxofre. ?leo esse que possui uma grande quantidade de CO2 dissolvido e assim uma solu??o pioneira para o destino desse g?s vem sendo a recupera??o avan?ada. O objetivo dessa pesquisa ? analisar quais os par?metros que tiveram maior influ?ncia no processo de recupera??o avan?ada. As simula??es foram realizadas utilizando o m?dulo GEM da Computer Modelling Group, com o objetivo de realizar estudos do m?todo de recupera??o avan?ada em quest?o. Para a realiza??o deste trabalho, modelos semi-sint?ticos foram utilizados com dados de reservat?rio e fluidos que podem ser extrapolados para situa??es pr?ticas do Nordeste brasileiro. Os resultados mostraram a influ?ncia do processo de inje??o alternada de ?gua e g?s sobre o fator de recupera??o e vaz?o de produ??o de ?leo, quando comparados ? recupera??o prim?ria e inje??o cont?nua de ?gua ou inje??o cont?nua de g?s

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Ribeiro, Robival Alves. "Correla??es nos dfa de diversos perfis geol?gicos. estudo de caso: Bacia de Campos - RJ." Universidade Federal do Rio Grande do Norte, 2010. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12917.

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This work aims to study the fluctuation structure of physical properties of oil well profiles. It was used as technique the analysis of fluctuations without trend (Detrended Fluctuation Analysis - DFA). It has been made part of the study 54 oil wells in the Campo de Namorado located in the Campos Basin in Rio de Janeiro. We studied five sections, namely: sonic, density, porosity, resistivity and gamma rays. For most of the profiles , DFA analysis was available in the literature, though the sonic perfile was estimated with the aid of a standard algorithm. The comparison between the exponents of DFA of the five profiles was performed using linear correlation of variables, so we had 10 comparisons of profiles. Our null hypothesis is that the values of DFA for the various physical properties are independent. The main result indicates that no refutation of the null hypothesis. That is, the fluctuations observed by DFA in the profiles do not have a universal character, that is, in general the quantities display a floating structure of their own. From the ten correlations studied only the profiles of density and sonic one showed a significant correlation (p> 0.05). Finally these results indicate that one should use the data from DFA with caution, because, in general, based on geological analysis DFA different profiles can lead to disparate conclusions
Esta disserta??o tem como objetivo estudar a estrutura de flutua??o de propriedades f?sicas dos perfis de po?os de petr?leo. Usou-se como t?cnica a an?lise de flutua??es sem tend?ncia (Detrended Fluctuation Analysis DFA). Fizeram parte do estudo 54 po?os de petr?leo do Campo de Namorado localizado na Bacia de Campos, no Estado do Rio de Janeiro. Foram estudados cinco perfis, quais sejam: s?nico, densidade, porosidade, resistividade e raios gama. Para a maioria dos perfis, a an?lise de DFA j? estava dispon?vel na literatura; entretanto o perfil s?nico foi estimado com o aux?lio de um algoritmo padr?o. A compara??o entre os expoentes de DFA dos cinco perfis foi feita usando correla??o linear de vari?veis; assim t?nhamos 10 compara??es de perfis. Nossa hip?tese nula ? que os valores de DFA para as diversas propriedades f?sicas s?o independentes. O principal resultado indica a n?o refuta??o da hip?tese nula. Isto ?, as flutua??es apresentadas pelos DFA dos perfis n?o apresentam um car?ter universal; ou seja, em geral, as grandezas exibem uma estrutura de flutua??o que lhes ? pr?pria. Das dez correla??es estudadas, apenas os perfis de densidade e o s?nico apresentaram uma correla??o significativa (p<0,05). Enfim, estes resultados indicam que se devem usar os dados de DFA com cautela, pois, em geral, an?lises geol?gicas baseadas em DFA de perfis diferentes podem levar a conclus?es d?spares

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Souza, Hiale Yane Silva de. "Estudo termoanal?tico da perlita hidrofobizada com ?leo de linha?a." Universidade Federal do Rio Grande do Norte, 2010. http://repositorio.ufrn.br:8080/jspui/handle/123456789/17640.

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In this work, expanded perlite, a mineral clay, consisting of SiO2 and Al2O3 in the proportions of 72.1 and 18.5%, respectively, was used as an adsorbent for oil in its pure expanded form as well as hydrofobized with linseed oil. Thermogravimetry (TG), Derivative Thermogravimetry (DTG) and Differential Thermal Analysis (DTA) were used to study the thermal behavior and quantify the percent adsorption of perlite in differents processes comparing the results with the ones obtained using Gravimetric Analysis. In the process of hydrophobization with linseed oil granulometric fractions > 20, 20-32 and 32-60 mesh were used and adsorption tests with crude oil were performed in triplicate at room temperature. The results obtained by TG/DTG in dynamic atmosphere of air showed mass losses in a single step for the expanded perlite with pure adsorbed oil, indicating that the adsorption of oil was limited and that the particle size did not in this process. Linseed oil has performed well as an agent of hydrophobized perlite (32 to 60 mesh) indicating a maximum percentage of 59.9% and 68.6% the linseed with a fraction range from considering the data obtained by thermogravimetry and Gravimetry, respectively. The adsorption of oil in the expanded perlite and hydrofobized pure perlite with linseed oil did not produce good results, characterizing an increase of 0.5 to 4.6% in pure perlite and 3.3% in hydrofobized perlite with granulometric 32 to 60 mesh
Nesse trabalho a perlita expandida, um argilomineral, constitu?do de SiO2 e Al2O3 nas propor??es de 72,1 e 18,5%, respectivamente foi utilizada como adsorvente para petr?leo na sua forma pura expandida como tamb?m hidrofobizada com ?leo de linha?a. Para isso, utilizou-se a Termogravimetria (TG), a Termogravimetria Derivada (DTG) e a An?lise T?rmica Diferencial (DTA) para estudar o comportamento t?rmico e verificar o percentual de adsor??o da perlita nos processos utilizados, em compara??o com a An?lise Gravim?trica. No processo de hidrofobiza??o com o ?leo de linha?a utilizou-se as fra??es > 20, 20 a 32 e 32 a 60 mesh e os testes de adsor??o com o petr?leo bruto foram realizados em triplicata em temperatura ambiente. Os resultados obtidos por TG/DTG em atmosfera din?mica de ar mostraram perdas de massa em uma ?nica etapa para a perlita expandida pura adsorvida com petr?leo, indicando que a adsor??o de petr?leo foi limitada e que a granulometria n?o interferiu nesse processo. O ?leo de linha?a apresentou bons resultados como agente hidrofobizante da perlita indicando um percentual m?ximo de 59,9% e 68,6% de linha?a na fra??o de 32 a 60 mesh considerando os dados obtidos por Termogravimetria e Gravimetria, respectivamente. A adsor??o do petr?leo na perlita pura expandida e na perlita hidrofobizada com ?leo de linha?a n?o apresentou bons resultados, caracterizando um aumento de 0,5 a 4,6% na perlita pura e 3,3 % na perlita hidrofobizada de 32 a 60 mesh

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Figueiredo, Aneli?se Lunguinho. "Pir?lise termoqu?mica de p?s da fibra de coco seco em um reator de cilindro rotativo para produ??o de bio-?leo." Universidade Federal do Rio Grande do Norte, 2011. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12952.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
This master thesis aims at developing a new methodology for thermochemical degradation of dry coconut fiber (dp = 0.25mm) using laboratory rotating cylinder reactor with the goal of producing bio-oil. The biomass was characterized by infrared spectroscopy with Fourier transform FTIR, thermogravimetric analysis TG, with evaluation of activation energy the in non-isothermal regime with heating rates of 5 and 10 ?C/min, differential themogravimetric analysis DTG, sweeping electron microscopy SEM, higher heating value - HHV, immediate analysis such as evaluated all the amounts of its main constituents, i.e., lignin, cellulose and hemicelluloses. In the process, it was evaluated: reaction temperature (450, 500 and 550oC), carrier gas flow rate (50 and 100 cm?/min) and spin speed (20 and 25 Hz) to condensate the bio-oil. The feed rate of biomass (540 g/h), the rotation of the rotating cylinder (33.7 rpm) and reaction time (30 33 min) were constant. The phases obtained from the process of pyrolysis of dry coconut fiber were bio-oil, char and the gas phase non-condensed. A macroscopic mass balance was applied based on the weight of each phase to evaluate their yield. The highest yield of 20% was obtained from the following conditions: temperature of 500oC, inert gas flow of 100 cm?/min and spin speed of 20 Hz. In that condition, the yield in char was 24.3%, non-condensable gas phase was 37.6% and losses of approximately 22.6%. The following physicochemical properties: density, viscosity, pH, higher heating value, char content, FTIR and CHN analysis were evaluated. The sample obtained in the best operational condition was subjected to a qualitative chromatographic analysis aiming to know the constituents of the produced bio-oil, which were: phenol followed by sirigol, acetovanilona and vinyl guaiacol. The solid phase (char) was characterized through an immediate analysis (evaluation of moisture, volatiles, ashes and fixed carbon), higher heating value and FTIR. The non-condensing gas phase presented as main constituents CO2, CO and H2. The results were compared to the ones mentioned by the literature.
O presente trabalho tem como objetivo o desenvolvimento de uma metodologia de degrada??o termoqu?mica da fibra do coco seco (dp = 0,25 mm) utilizando reator de cilindro rotativo em escala de laborat?rio, visando a produ??o de bio-?leo. A biomassa foi caracterizada por an?lise elementar (C, H, N), espectroscopia no infravermelho com transformada de Fourier - IVTF, an?lise termogravim?trica ATG, com avalia??o da energia de ativa??o no regime n?o isot?rmico com taxas de aquecimento de 5 e 10 oC/min, an?lise diferencial termogravim?trica - DTG, microscopia eletr?nica de varredura - MEV, poder calor?fico superior - PCS, an?lise imediata (avalia??o da umidade, materiais vol?teis, cinzas e carbono fixo) bem como avalia??o dos teores dos principais constituintes, ou seja, lignina, celulose e hemicelulose. No processo de pir?lise os seguintes par?metros foram estudados: temperatura da rea??o (450, 500 e 550 ?C), vaz?o do g?s de arraste (50 e 100 cm?/min) e velocidade de centrifuga??o para condensa??o do bio-?leo (20 e 25 Hz). O fluxo de alimenta??o da biomassa (540 g/h), a rota??o do cilindro rotativo (33,7 rpm) e o tempo de rea??o (30 33 min) foram mantidos constantes. Os produtos obtidos no processo da pir?lise da fibra do coco seco foram o bio-?leo, os finos de carv?o e a fase gasosa n?o condensada. Um balan?o de massa macrosc?pico aplicado tendo como base o peso de cada produto permitiu obter o rendimento dessas fases. O melhor rendimento de 18,1 % em bio-?leo foi obtido nas seguintes condi??es: temperatura de 500 ?C, vaz?o de g?s inerte 100 cm?/min e velocidade de centrifuga??o de 20 Hz. Nessas condi??es, o rendimento em finos de carv?o foi de 21,7 %, fase gasosa n?o condens?vel 37,6 % e perdas da ordem de 22,6 %. Algumas propriedades f?sicas do bio-?leo foram avaliadas, a saber, a densidade, viscosidade, pH, poder calor?fico superior, teor de finos de carv?o, an?lise por IVTF e CHN. A an?lise cromatogr?fica do bio-?leo mostrou que os principais constituintes de sua composi??o foram o fenol seguido do sirigol, aceto vanilona e vinil guaiacol. A fase s?lida (finos de carv?o) obtida foi caracterizada por an?lise imediata, poder calor?fico superior e IVTF. A fase gasosa n?o condensada apresentou como principais constituintes o CO2, CO e H2. Os resultados foram comparados com dados da literatura.

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Silva, Ivanovitch Medeiros Dantas da. "An?lise de desempenho de sistemas de comunica??o sem-fio para monitoramento de unidade de produ??o de po?os petrol?feros terrestres." Universidade Federal do Rio Grande do Norte, 2008. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15199.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
The greater part of monitoring onshore Oil and Gas environment currently are based on wireless solutions. However, these solutions have a technological configuration that are out-of-date, mainly because analog radios and inefficient communication topologies are used. On the other hand, solutions based in digital radios can provide more efficient solutions related to energy consumption, security and fault tolerance. Thus, this paper evaluated if the Wireless Sensor Network, communication technology based on digital radios, are adequate to monitoring Oil and Gas onshore wells. Percent of packets transmitted with successful, energy consumption, communication delay and routing techniques applied to a mesh topology will be used as metrics to validate the proposal in the different routing techniques through network simulation tool NS-2
Grande parte do monitoramento de po?os petrol?feros terrestres realizados atualmente est? baseado em solu??es sem fio (wireless). Todavia, essas solu??es apresentam uma configura??o defasada tecnologicamente na medida em que s?o utilizados r?dios anal?gicos e topologias de comunica??o ineficientes. Por outro lado, tecnologias que adotam r?dios digitais podem proporcionar solu??es mais eficientes relacionadas com o consumo de energia, seguran?a e toler?ncia a falhas. O trabalho investiga se as Redes de Sensores Sem Fio, tecnologia de comunica??o que utiliza r?dios digitais, s?o adequadas para o monitoramento de po?os petrol?feros terrestres. Porcentagem de pacotes entregues com sucesso, consumo de energia, atrasos de comunica??o e t?cnicas de roteamento para uma topologia em malha s?o as m?tricas usadas para validar a proposta atrav?s da ferramenta de simula??o NS-2

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Silva, ?talo Batista da. "Compara??o da an?lise de diferentes perfis de po?os pelo m?todo DFA." Universidade Federal do Rio Grande do Norte, 2014. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12988.

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The study of complex systems has become a prestigious area of science, although relatively young . Its importance was demonstrated by the diversity of applications that several studies have already provided to various fields such as biology , economics and Climatology . In physics , the approach of complex systems is creating paradigms that influence markedly the new methods , bringing to Statistical Physics problems macroscopic level no longer restricted to classical studies such as those of thermodynamics . The present work aims to make a comparison and verification of statistical data on clusters of profiles Sonic ( DT ) , Gamma Ray ( GR ) , induction ( ILD ) , neutron ( NPHI ) and density ( RHOB ) to be physical measured quantities during exploratory drilling of fundamental importance to locate , identify and characterize oil reservoirs . Software were used : Statistica , Matlab R2006a , Origin 6.1 and Fortran for comparison and verification of the data profiles of oil wells ceded the field Namorado School by ANP ( National Petroleum Agency ) . It was possible to demonstrate the importance of the DFA method and that it proved quite satisfactory in that work, coming to the conclusion that the data H ( Hurst exponent ) produce spatial data with greater congestion . Therefore , we find that it is possible to find spatial pattern using the Hurst coefficient . The profiles of 56 wells have confirmed the existence of spatial patterns of Hurst exponents , ie parameter B. The profile does not directly assessed catalogs verification of geological lithology , but reveals a non-random spatial distribution
O estudo dos sistemas complexos tornou-se uma ?rea prestigiada da ci?ncia, apesar de ser relativamente jovem. Sua import?ncia foi comprovada pela diversidade de aplica??es que v?rios estudos j? proporcionaram para campos diversos como os da Biologia, Economia e Climatologia. Na F?sica, a abordagem dos sistemas complexos vem criando paradigmas que influenciam de forma marcante os novos m?todos, trazendo para a F?sica Estat?stica problemas de n?vel macrosc?pico n?o mais restritos a estudos cl?ssicos como os da Termodin?mica. O presente trabalho tem como objetivo fazer uma compara??o e verifica??o dos aglomerados estat?sticos de dados relativos aos perfis de S?nico (DT), Raio Gama (GR), Indu??o (ILD), Neutr?nico (NPHI) e Densidade (RHOB) por serem grandezas f?sicas medidas durante a perfura??o de po?os explorat?rios de fundamental import?ncia para localizar, identificar e caracterizar reservat?rios de petr?leo. Foram utilizados os softwares: Statistica, Matlab R2006a, Origin 6.1 e Fortran para a compara??o e verifica??o dos dados dos perfis de po?os de petr?leo da Escola Campo Namorado cedidos pela ANP (Ag?ncia nacional de petr?leo). Foi poss?vel evidenciar a import?ncia do m?todo DFA e que o mesmo mostrou-se bastante satisfat?rio no referido trabalho, chegando-se a conclus?o que os dados do H (expoente de Hurst) produzem dados espaciais com uma maior aglomera??o. Portanto, constatamos que ? poss?vel encontrar padr?o espacial usando o coeficiente de Hurst. Os perfis dos 56 po?os comprovaram a exist?ncia de padr?es espaciais dos expoentes de Hurst, ou seja, par?metro B. O perfil avaliado n?o cataloga diretamente a verifica??o da litologia geol?gica, mas revela a exist?ncia de uma distribui??o espacial n?o aleat?ria
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Fontes, L?cio ?ngelo de Oliveira. "Desenvolvimento de uma unidade pirol?tica com reator de cilindro rotativo: obten??o de bio-?leo." Universidade Federal do Rio Grande do Norte, 2011. http://repositorio.ufrn.br:8080/jspui/handle/123456789/13011.

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The demand for alternative sources of energy drives the technological development so that many fuels and energy conversion processes before judged as inadequate or even non-viable, are now competing fuels and so-called traditional processes. Thus, biomass plays an important role and is considered one of the sources of renewable energy most important of our planet. Biomass accounts for 29.2% of all renewable energy sources. The share of biomass energy from Brazil in the OIE is 13.6%, well above the world average of participation. Various types of pyrolysis processes have been studied in recent years, highlighting the process of fast pyrolysis of biomass to obtain bio-oil. The continuous fast pyrolysis, the most investigated and improved are the fluidized bed and ablative, but is being studied and developed other types in order to obtain Bio-oil a better quality, higher productivity, lower energy consumption, increased stability and process reliability and lower production cost. The stability of the product bio-oil is fundamental to designing consumer devices such as burners, engines and turbines. This study was motivated to produce Bio-oil, through the conversion of plant biomass or the use of its industrial and agricultural waste, presenting an alternative proposal for thermochemical pyrolysis process, taking advantage of particle dynamics in the rotating bed that favors the right gas-solid contact and heat transfer and mass. The pyrolyser designed to operate in a continuous process, a feeder containing two stages, a divisive system of biomass integrated with a tab of coal fines and a system of condensing steam pyrolytic. The prototype has been tested with sawdust, using a complete experimental design on two levels to investigate the sensitivity of factors: the process temperature, gas flow drag and spin speed compared to the mass yield of bio-oil. The best result was obtained in the condition of 570 oC, 25 Hz and 200 cm3/min, temperature being the parameter of greatest significance. The mass balance of the elementary stages presented in the order of 20% and 37% liquid pyrolytic carbon. We determined the properties of liquid and solid products of pyrolysis as density, viscosity, pH, PCI, and the composition characterized by chemical analysis, revealing the composition and properties of a Bio-oil.
A demanda por fontes alternativas de energia impulsiona o desenvolvimento tecnol?gico de tal forma que muitos combust?veis e processos de convers?o energ?tica, antes julgada como inadequados ou mesmo invi?veis, s?o agora concorrentes de combust?veis e processos ditos tradicionais. Assim, a biomassa exerce um papel relevante, sendo considerada uma das fontes de energia renov?vel mais importante de nosso planeta. A biomassa contribui com 29,2 % de todas as fontes renov?veis de energia. A participa??o de energia de biomassa do Brasil na OIE ? de 13,6 %, sendo bem superior a m?dia mundial de participa??o. V?rios tipos de processos de pir?lise v?m sendo estudados nos ?ltimos anos, destacando-se o processo de pir?lise r?pida de biomassa para obten??o de Bio-?leo. Os processos cont?nuos de pir?lise r?pida, mais investigados e aprimorados s?o os de leito fluidizado e leito ablativo, entretanto vem sendo estudados e desenvolvidos outros tipos, visando obter um bio-?leo de melhor qualidade, com maior produtividade, menor consumo de energia, maior estabilidade e confiabilidade de processo e menor custo de produ??o. A estabilidade do produto Bio-?leo ? fundamental para a concep??o de dispositivos consumidores, tais como queimadores, motores de pist?o e turbinas. O presente estudo foi motivado para a produ??o de Bio-?leo, atrav?s da convers?o da biomassa vegetal ou do aproveitamento de seus res?duos industriais e agr?colas, sendo apresentada uma proposta alternativa de processo de pir?lise termoqu?mica, aproveitando a vantagem din?mica das part?culas no leito rotativo o que favorece a raz?o de contato g?s-s?lido e a transfer?ncia de calor e massa. O pirolisador foi projetado para operar em processo cont?nuo, contendo um alimentador de dois est?gios, um sistema desagregador da biomassa integrado com um separador de finos de carv?o e um sistema de condensa??o de vapores pirol?ticos. O Prot?tipo foi submetido a ensaios com serragem de madeira, utilizando um planejamento experimental completo em dois n?veis para investigar a sensibilidade dos fatores: temperatura do processo, fluxo de g?s de arraste e velocidade de centrifuga??o em rela??o ao rendimento m?ssico de Bio-?leo. O melhor resultado foi obtido na condi??o de 570 oC, 25 Hz e 200 cm3/min, sendo a temperatura o par?metro de maior signific?ncia. O balan?o Tese de Doutorado PPGCEP/UFRN L?cio ?ngelo de Oliveira Fontes vi de massa elementar das fases apresentou da ordem de 20 % liquidos pirol?ticos e 37 % de carv?o. Foram determinadas as propriedades dos produtos l?quidos e s?lidos da pir?lise como densidade, viscosidade, pH, PCI, sendo a composi??o caracterizada atrav?s an?lise qu?mica, revelando as propriedades e composi??o de um Bio-?leo.

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Santos, Frances Regiane dos. "Estudo comparativo dos ?leos essenciais de esp?cies da fam?lia Myrtaceae atrav?s do perfil cromatogr?fico, an?lise multivariada e atividades biol?gicas." Universidade Federal Rural do Rio de Janeiro, 2016. https://tede.ufrrj.br/jspui/handle/jspui/1971.

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The Myrtaceae family comprises more than 3,500 species, which are widely distributed on all continents (except Antarctica). The chemical diversity and the biological potential of essential oils extracted from fresh leaves of Myrtaceae species cultivated in the Botanical Garden of UFRRJ were described. Six different species were studied: Eugenia uniflora L. (?pitanga?), Eugenia brasiliensis L. (?grumixama?), Psidium cattleianum Sabine (?ara???), Psidium guajava L. (?goiaba?), Syzygium cumini (?jamel?o?) and Syzygium malaccense (L.) (?jambo?). Chemical, statistical and biological methods were used, with the aid of chromatographic analysis (GC-FID and GC-MS), chemometrics (PCA and HCA statistical analysis) and biological activities (larvicide, trypanocidal, fungicidal and antioxidant) to determine these essencial oils. The essential oil of species E. uniflora L, E. brasiliensis, P.cattleianum and P. guajava showed mainly sesquiterpenes in its compositions, while the oil from S. cumini was rich in monoterpenes and S. malaccense presented, mostly, chemical constituents not derived isoprene metabolites.. The chemometric analysis of GC-MS data of the oils extracted from leaves of six species, discriminated three groups of essential oils, according to the similarity of the composition of volatile components for each species. Specifically, for the P.cattleianum and P. guajava data, the ?-caryophyllene and ?-humuleno constituents could be considered markers of Psidium genus. The biological results suggested that the essential oils of the species studied were effective as they showed larvicide and fungicidal activity . The essential oil of E. uniflora and its isolated furanodiene showed antioxidant activity, with the TBARS method, and also showed potential anti-Trypanosoma cruzi activity, which suggests that both are an interesting alternative to combat infectious diseases such as Chagas disease
A fam?lia Myrtaceae compreende mais de 3.500 esp?cies, que est?o amplamente distribu?das por todos os continentes (exceto Ant?rtida). Este trabalho descreve a diversidade qu?mica e o potencial biol?gico dos ?leos essenciais extra?dos de folhas frescas de esp?cies de Myrtaceae cultivadas no Jardim Bot?nico da UFRRJ. Seis esp?cies diferentes foram estudadas: Eugenia uniflora L.(pitangueira), Eugenia brasiliensis Lam (grumixameira), Psidium cattleianum Sabine (ara?azeiro), Psidium guajava L. (goiabeira), Syzygium cumini (jameleiro) e Syzygium malaccense (L.) Merr. & L. M. Perry (jambeiro vermelho). Os seus ?leos essenciais foram extra?dos por hidrodestila??o e avaliados com o aux?lio de an?lises cromatogr?ficas (CG-DIC e CG-EM), quimiometria (utilizando An?lise de Componentes Principais - ACP e An?lise de Agrupamentos Hier?rquicos ? AAH) e atrav?s de atividades biol?gicas (larvicida, tripanocida, fungicida e antioxidante). O ?leo essencial das esp?cies E. uniflora L, E. brasiliensis P.cattleianum e P. guajava apresentou, principalmente, sesquiterpenos em sua composi??o, enquanto o ?leo de S. cumini foi rico em monoterpenos e o de S. malaccense apresentou constituintes qu?micos n?o oriundos de metab?litos do isopreno. Os resultados obtidos atrav?s da quantifica??o e identifica??o qu?mica dos ?leos essenciais por Cromatografia em Fase Gasosa acoplada a Espectrometria de Massas (CG-EM) aplicadas ?s an?lises quimiom?tricas permitiu discriminar tr?s agrupamentos de ?leos essenciais, de acordo com a similaridade na composi??o de constituintes vol?teis para cada esp?cie. Especificamente para P. cattleianum e P. guajava os constituintes ?-cariofileno e ?-humuleno foram considerados os marcadores do g?nero Psidium. Para os ensaios biol?gicos realizados, os resultados obtidos com os ?leos essenciais das esp?cies estudadas mostraram-se eficazes quanto ? atividade larvicida e fungicida. O ?leo essencial de E. uniflora e o furanodieno isolado apresentaram atividade antioxidante pelo m?todo TBARS, e tamb?m apresentaram potencial atividade tripanocida, sugerindo que ambos sejam uma alternativa interessante para combater doen?as parasit?rias como a doen?a de Chagas

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Mata, Maria das Vit?rias Medeiros da. "An?lise de agrupamentos dos dados de DFA oriundos de perfis el?tricos de indu??o de po?os de petr?leo." Universidade Federal do Rio Grande do Norte, 2009. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12902.

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The main objective of this study is to apply recently developed methods of physical-statistic to time series analysis, particularly in electrical induction s profiles of oil wells data, to study the petrophysical similarity of those wells in a spatial distribution. For this, we used the DFA method in order to know if we can or not use this technique to characterize spatially the fields. After obtain the DFA values for all wells, we applied clustering analysis. To do these tests we used the non-hierarchical method called K-means. Usually based on the Euclidean distance, the K-means consists in dividing the elements of a data matrix N in k groups, so that the similarities among elements belonging to different groups are the smallest possible. In order to test if a dataset generated by the K-means method or randomly generated datasets form spatial patterns, we created the parameter Ω (index of neighborhood). High values of Ω reveals more aggregated data and low values of Ω show scattered data or data without spatial correlation. Thus we concluded that data from the DFA of 54 wells are grouped and can be used to characterize spatial fields. Applying contour level technique we confirm the results obtained by the K-means, confirming that DFA is effective to perform spatial analysis
O principal objetivo do presente trabalho foi aplicar m?todos recentemente desenvolvidos em f?sica-estat?stica ?s s?ries temporais, em especial a dados de perfis el?tricos de indu??o de 54 po?os de petr?leo localizados no Campo de Namorado Bacia de Campos - RJ, para estudar a similaridade petrof?sica dos po?os numa distribui??o espacial. Para isto, utilizamos o m?todo do DFA com o intuito de saber se podemos, ou n?o, utilizar esta t?cnica para caracterizar espacialmente o campo. Depois de obtidos os valores de DFA para todos os po?os, fizemos uma an?lise de agrupamento com rela??o a estas caracter?sticas; para tanto, utilizamos o m?todo de agrupamento n?o-hier?rquico chamado m?todo K-m?dia. Geralmente baseado na dist?ncia euclidiana, o K-m?dia consiste em dividir os elementos de uma matriz n de dados em k grupos bem definidos, de maneira que as semelhan?as existentes entre elementos pertencentes a grupos distintos sejam as menores poss?veis. Com o objetivo de verificar se um conjunto de dados gerados pelo m?todo do K-m?dia ou gerado aleatoriamente forma padr?es espaciais, criamos o par?metro Ω (?ndice de vizinhan?a). Altos valores de Ω implicam em dados mais agregados e baixos valores de Ω em dados dispersos ou sem correla??o espacial. Com aux?lio do m?todo de Monte Carlo observamos que dados agrupados aleatoriamente apresentam uma distribui??o de Ω inferior ao valor emp?rico. Desta forma conclu?mos que os dados de DFA obtidos nos 54 po?os est?o agrupados e podem ser usados na caracteriza??o espacial de campos. Ao cruzar os dados das curvas de n?vel com os resultados obtidos pelo K-m?dia, confirmamos a efici?ncia do mesmo para correlacionar po?os em distribui??o espacial

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Gadré, Karine. "Conception d'un modèle de visibilité d'étoile à l'oeil nu : application à l'identification des décans égyptiens." Phd thesis, Université Paul Sabatier - Toulouse III, 2008. http://tel.archives-ouvertes.fr/tel-00361227.

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Sur l'intérieur du couvercle de sarcophages, sur la surface extérieure de clepsydres, au plafond de temples et de tombes datés de l'an 2100 à l'an 50 BC et disséminés tout le long de la Vallée du Nil, entre Alexandrie et Assouan, figurent vingt horloges stellaires et quatre-vingt listes d'étoiles dans l'ordre de leurs levers héliaques, de leurs levers nocturnes ou de leurs culminations. Leur identification à des étoiles visibles à l'oeil nu du catalogue Hipparcos a nécessité la constitution préalable d'une liste complète de ces étoiles ainsi que la traduction de leurs appellations hiéroglyphiques respectives. La comparaison entre les arrangements stellaires caractérisant chacune des cent listes d'étoiles a abouti à leur classification en six types de listes et permis la détermination des conditions spatiales, temporelles et optiques d'observation des étoiles. Ces contraintes ont ensuite été appliquées à un modèle de visibilité d'étoile à l'oeil nu dans le ciel nocturne ou crépusculaire de l'Égypte ancienne qui combine divers paramètres astrométriques et éléments photométriques. La constitution de listes d'étoiles dans l'ordre de leurs levers héliaques, de leurs levers nocturnes ou de leurs culminations, leur comparaison avec les six prototypes de listes dont nous disposons, la prise en compte de divers critères astronomiques, philologiques et pariétaux, ont permis de restreindre au strict minimum le nombre d'étoiles candidates à chacun des quatre-vingt dix décans égyptiens. Ce travail a abouti à la cartographie du ciel de l'Égypte ancienne, à une meilleure définition des heures de nuit égyptienne, à une datation plus précise du règne de plusieurs pharaons, etc.

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Avelar, Karen Pereira Batista de. "Estudo da influ?ncia da temperatura na degrada??o termoqu?mica da biomassa de avel?s." Universidade Federal do Rio Grande do Norte, 2013. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15844.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
The bio-oil obtained from the pyrolysis of biomass has appeared as inter-esting alternative to replace fossil fuels. The aim of this work is to evaluate the influence of temperature on the yield of products originating from the pyrolysis process of the powder obtained from the dried twigs of avel?s (Euphorbia tirucalli), using a rotating cylinder reactor in laboratory scale. The biomass was treated and characterized by: CHNS, moisture, volatiles, fixed carbon and ashes, as well as evaluation of lignin, cellulose and hemicellulose, besides other instrumental techniques such as: FTIR, TG/DTG, DRX, FRX and MEV. The activation energy was evaluated in non-isothemichal mode with heating rates of 5 and 10 oC/min. The obtained results showed biomass as feedstock with potential for biofuel production, because presents a high organic matter content (78,3%) and fixed-carbon (7,11%). The activation energy required for the degradation of biomass ranged between 232,92 392,84 kJ/mol, in the temperature range studied and heating rate of 5 and 10?C/min. In the pyrolysis process, the influence of the reaction temperature was studied (350-520 ? C), keeping constant the other variables, such as, the flow rate of carrier gas, the centrifugal speed for the bio-oil condensationa, the biomass flow and the rotation of the reactor. The maximum yield of bio-oil was obtained in the temperature of 450?C. In this temperature, the results achieved where: content of bio-oil 8,12%; char 32,7%; non-condensed gas 35,4%; losts 23,8%; gross calorific value 3,43MJ/kg; pH 4,93 and viscosity 1,5cP. The chromatographic analysis of the bio-oil produced under these conditions shows mainly the presence of phenol (17,71%), methylciclopentenone (10,56%) and dimethylciclopentenone (7,76%)
O bio-?leo obtido da pir?lise da biomassa tem aparecido como alternativa interessante para substitui??o dos combust?veis f?sseis. O objetivo deste trabalho ? avaliar a influ?ncia da temperatura no rendimento dos produtos originados do processo de pir?lise do p? obtido dos galhos secos do avel?s (Euphorbia tirucalli), utilizando um reator de cilindro rotativo em escala de laborat?rio. A biomassa foi tratada e caracterizada por: CHNS, umidade, materiais vol?teis, cinzas e carbono fixo, bem como, avalia??o dos teores de lignina, celulose e hemicelulose, al?m de outras t?cnicas instrumentais, tais como: FTIR, TG/DTG, DRX, FRX e MEV. A energia de ativa??o foi avaliada no regime n?o isot?rmico com taxas de aquecimento de 5 e 10 oC/min. Os resultados obtidos mostraram a biomassa como mat?ria prima com potencial para produ??o de biocombust?veis, pois apresenta alto teor de mat?ria org?nica (78,3%) e carbono fixo (7,11%). A energia de ativa??o exigida para degrada??o da biomassa variou entre 232,92 392,84 kJ/mol, no intervalo de temperatura da rea??o estudado e taxa de aquecimento de 5 e 10oC/min. No processo de pir?lise, estudou-se a influ?ncia da temperatura da rea??o (350-520 ?C), mantendo-se constantes as demais vari?veis, ou seja, a vaz?o do g?s de arraste , a velocidade de centrifuga??o para condensa??o do bio-?leo, a vaz?o de biomassa e a rota??o do reator. O rendimento m?ximo em bio-?leo foi obtido na temperatura de 450?C. Nessa temperatura, os resultados alcan?ados foram: teor de bio?leo de 8,12%; carv?o 32,7%; fase gasosa n?o condensada 35,4%; perdas 23,8%; poder calor?fico superior 3,43MJ/kg; pH 4,93; viscosidade 1,5cP. A an?lise cromatogr?fica do bio-?leo produzido nessas condi??es mostra a presen?a, principalmente, de fenol (17,71%), metilciclopentenona (10,56%) e dimetilciclopentenona (7,76%)

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Costa, Maria Jos? Fonseca. "S?ntese e caracteriza??o de materiais nanoporosos para pir?lise catal?tica de ?leos pesados." Universidade Federal do Rio Grande do Norte, 2008. http://repositorio.ufrn.br:8080/jspui/handle/123456789/17609.

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The present work reports the study of nanoporous structures, aiming at their use in research directed to the current demand of the petroleum industry to value heavy oil. Initially, two ways were chosen for the synthesis of porous structures from the molecular sieves of type Si-MCM-41. In the first way, the structure MCM-41 is precursory for heteroatom substitutes of silicon, generating catalyst of the type Al-MCM-41 from two different methods of incorporation of the metal. This variation of the incorporation method of Aluminum in the structure of Si-MCM-41 was carried out through the conventional procedure, where the aluminum source was incorporated to the gel of synthesis, and the procedure post-synthesis, where the Aluminum source was incorporated in catalyst after the synthesis of Si-MCM-41. In the second way, the MCM-41 acts as a support for growth of nanocrystals of zeolite embedded in their mesoporous, resulting in hybrid MCM-41/ZSM-5 catalyst. A comparative analysis was carried through characterizations by XRD, FTIR, measures of acidity through n-butylamine adsorption for TGA, SEM-XRF and N2 adsorption. Also crystalline aluminosilicate with zeolitic structure MFI of type ZSM-5 was synthesized without using organic templates. Methodologies to the preparation of these materials are related by literature using conventionally reactants that supply oxides of necessary silicon and aluminum, as well as a template agent, and in some cases co-template. The search for new routes of preparation for the ZSM-5 aimed at, above all, the optimization of the same as for the time and the temperature of synthesis, and mainly the elimination of the use of organic templates, that are material of high cost and generally very toxic. The current study is based on the use of the H2O and Na+ cations playing the role of structural template and charge compensation in the structure. Characterizations by XRD, FTIR, SEM-XRF and N2 adsorption were also conducted for this material in order to compare the samples of ZSM-5 synthesized in the absence of template and those used industrially and synthesized using structuring
O presente trabalho relata o estudo de estruturas nanoporosas, visando o uso em pesquisas que atendam a atual demanda da ind?stria do petr?leo, de valorizar ?leos pesados. Inicialmente, optou-se por duas vertentes para a s?ntese de estruturas porosas a partir da peneira molecular do tipo Si-MCM-41. Na primeira vertente, a estrutura MCM-41 ? precursora para hetero?tomos substituintes do sil?cio, gerando catalisadores do tipo Al-MCM-41 a partir de dois diferentes m?todos de incorpora??o do metal. Essa varia??o do m?todo de incorpora??o do Alum?nio na estrutura do Si-MCM-41 se deu atrav?s do procedimento convencional, no qual a fonte de alum?nio foi incorporada ao gel de s?ntese e do procedimento p?s-s?ntese, no qual a fonte de Alum?nio foi incorporada ao catalisador ap?s a s?ntese do Si-MCM-41. Na segunda vertente, o MCM-41 age como suporte para o crescimento de nanocristais de ze?lita embutidos nos seus mesoporos, resultando no catalisador h?brido MCM-41/ZSM-5. Uma an?lise comparativa foi realizada atrav?s de caracteriza??es por XRD, FTIR, medidas de acidez atrav?s de dessor??o de n-butilamina por TGA, SEM-XRF e Adsor??o de N2. Tamb?m foi sintetizado um aluminossilicato cristalino com estrutura zeol?tica MFI do tipo ZSM-5, na aus?ncia total de direcionador org?nico. Metodologias relacionadas ? prepara??o desses materiais s?o relatadas pela literatura utilizando-se convencionalmente reagentes que forne?am os ?xidos de sil?cio e de alum?nio necess?rios, bem como um agente direcionador, e em alguns casos at? co-direcionadores. A busca por novas rotas de prepara??o para a ZSM-5 visou, sobretudo, a otimiza??o da mesma no que se refere ao tempo e ? temperatura de s?ntese, e principalmente a elimina??o do uso dos direcionadores org?nicos, que s?o materiais de alto custo e geralmente muito t?xicos. O atual estudo se baseia na utiliza??o da H2O e dos c?tions Na+ desempenhando o papel de direcionamento estrutural e compensa??o de cargas na estrutura. Caracteriza??es por XRD, FTIR, SEM-XRF e Adsor??o de N2 tamb?m foram realizadas para esse material, a fim de comparar as amostras de ZSM-5 sintetizadas na aus?ncia do direcionador e aquelas utilizadas industrialmente e sintetizadas utilizando estruturantes

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Paiva, Maria das Dores Macedo. "Otimiza??o e an?lise mec?nica de pastas geopolim?ricas para uso em po?os sujeitos ? inje??o c?clica de vapor." Universidade Federal do Rio Grande do Norte, 2008. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12729.

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Oil wells subjected to cyclic steam injection present important challenges for the development of well cementing systems, mainly due to tensile stresses caused by thermal gradients during its useful life. Cement sheath failures in wells using conventional high compressive strength systems lead to the use of cement systems that are more flexible and/or ductile, with emphasis on Portland cement systems with latex addition. Recent research efforts have presented geopolymeric systems as alternatives. These cementing systems are based on alkaline activation of amorphous aluminosilicates such as metakaolin or fly ash and display advantageous properties such as high compressive strength, fast setting and thermal stability. Basic geopolymeric formulations can be found in the literature, which meet basic oil industry specifications such as rheology, compressive strength and thickening time. In this work, new geopolymeric formulations were developed, based on metakaolin, potassium silicate, potassium hydroxide, silica fume and mineral fiber, using the state of the art in chemical composition, mixture modeling and additivation to optimize the most relevant properties for oil well cementing. Starting from molar ratios considered ideal in the literature (SiO2/Al2O3 = 3.8 e K2O/Al2O3 = 1.0), a study of dry mixtures was performed,based on the compressive packing model, resulting in an optimal volume of 6% for the added solid material. This material (silica fume and mineral fiber) works both as an additional silica source (in the case of silica fume) and as mechanical reinforcement, especially in the case of mineral fiber, which incremented the tensile strength. The first triaxial mechanical study of this class of materials was performed. For comparison, a mechanical study of conventional latex-based cementing systems was also carried out. Regardless of differences in the failure mode (brittle for geopolymers, ductile for latex-based systems), the superior uniaxial compressive strength (37 MPa for the geopolymeric slurry P5 versus 18 MPa for the conventional slurry P2), similar triaxial behavior (friction angle 21? for P5 and P2) and lower stifness (in the elastic region 5.1 GPa for P5 versus 6.8 GPa for P2) of the geopolymeric systems allowed them to withstand a similar amount of mechanical energy (155 kJ/m3 for P5 versus 208 kJ/m3 for P2), noting that geopolymers work in the elastic regime, without the microcracking present in the case of latex-based systems. Therefore, the geopolymers studied on this work must be designed for application in the elastic region to avoid brittle failure. Finally, the tensile strength of geopolymers is originally poor (1.3 MPa for the geopolymeric slurry P3) due to its brittle structure. However, after additivation with mineral fiber, the tensile strength became equivalent to that of latex-based systems (2.3 MPa for P5 and 2.1 MPa for P2). The technical viability of conventional and proposed formulations was evaluated for the whole well life, including stresses due to cyclic steam injection. This analysis was performed using finite element-based simulation software. It was verified that conventional slurries are viable up to 204?F (400?C) and geopolymeric slurries are viable above 500?F (260?C)
Po?os sujeitos ? inje??o c?clica de vapor apresentam importantes desafios para desenvolvimento de pastas de cimenta??o, devido principalmente aos esfor?os de tra??o causados pelos gradientes t?rmicos durante a sua vida ?til. Falhas em cimenta??es que empregaram pastas convencionais de elevada resist?ncia ? compress?o levaram ao emprego de pastas mais flex?veis e/ou d?cteis, com destaque para as pastas de cimento Portland com adi??o de l?tex. Recentes pesquisas t?m apresentado pastas geopolim?ricas como alternativa. Estas pastas cimentantes s?o baseadas na ativa??o alcalina de aluminosilicatos amorfos como o metacaulim ou a cinza volante e possuem propriedades vantajosas como alta resist?ncia ? compress?o, r?pido endurecimento e estabilidade t?rmica. Encontram-se na literatura formula??es geopolim?ricas b?sicas que atendem ?s especifica??es da ind?stria de petr?leo, incluindo reologia, resist?ncia ? compress?o e tempo de espessamento. Neste trabalho, desenvolveu-se novas formula??es geopolim?ricas ? base de metacaulim, silicato de pot?ssio, hidr?xido de pot?ssio, micross?lica e fibra mineral, utilizando o estado da arte em composi??o qu?mica, modelagem de misturas e aditiva??o para otimizar as propriedades relevantes para a cimenta??o de po?os. Partindo de raz?es molares consideradas ideais na literatura (SiO2/Al2O3 = 3,8 e K2O/Al2O3 = 1,0), realizou-se um estudo de misturas secas baseado no modelo do empacotamento compress?vel, obtendo-se um volume ?timo de 6% para o material s?lido adicional. Este material (micross?lica e fibra mineral) serve tanto como fonte de s?lica adicional (no caso da micross?lica) quanto refor?o mec?nico, principalmente no caso da fibra mineral, a qual incrementou a resist?ncia ? tra??o. Realizou-se o primeiro estudo mec?nico triaxial desta classe de pastas. Para efeito de compara??o, tamb?m foi realizado um estudo mec?nico de pastas convencionais ? base de l?tex. Apesar de diferen?as no modo de ruptura (fr?gil no caso dos geopol?meros, d?ctil no caso das pastas com l?tex), a superior resist?ncia compressiva uniaxial (37 MPa para a pasta geopolim?rica P5 versus 18 MPa para a pasta convencional P2), comportamento triaxial similar (?ngulo de atrito 21? para P5 e P2) e menor rigidez (na regi?o el?stica 5,1 GPa para P5 versus 6,8 GPa para P2) das pastas geopolim?ricas permitiu uma capacidade de absor??o de energia (155 kJ/m3 para P5 versus 208 kJ/m3 para P2) compar?vel entre as duas, sendo que os geopol?meros atuam no regime el?stico, sem a microfissura??o presente nas pastas com l?tex. Assim, os geopol?meros estudados neste trabalho devem ser dimensionados para aplica??es no regime el?stico para evitar fraturas fr?geis. Finalmente, a resist?ncia ? tra??o do geopol?mero ? originalmente pobre (1,3 MPa para a pasta geopolim?rica P3) devido ? sua estrutura fr?gil. Entretanto, ap?s a aditiva??o desse sistema com fibra mineral, a resist?ncia ? tra??o do mesmo tornou-se equivalente (2,3 MPa para P5 e 2,1 MPa para P2) ? das pastas com l?tex. A viabilidade t?cnica das formula??es convencionais e geopolim?ricas foi avaliada durante toda a vida ?til do po?o, incluindo os esfor?os devidos ? inje??o c?clica de vapor. Esta an?lise foi feita utilizando um software de simula??o ? base de elementos finitos. Verificou-se que as pastas convencionais s?o vi?veis at? a temperatura de 204?C (400?F) e as geopolim?ricas acima de 260?C (500?F)

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Lacerda, Junior Jonatas Araujo de. "Projeto, constru??o e an?lise de um prototipo vibracional em escala de bancada aplic?vel ao tratamento de ?gua de produ??o de petr?leo bruto, mediante inovadora opera??o h?brida de adsor??o e auto-flota??o." Universidade Federal do Rio Grande do Norte, 2014. http://repositorio.ufrn.br:8080/jspui/handle/123456789/13037.

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A self-flotator vibrational prototype electromechanical drive for treatment of oil and water emulsion or like emulsion is presented and evaluated. Oil production and refining to obtain derivatives is carried out under arrangements technically referred to as on-shore and off-shore, ie, on the continent and in the sea. In Brazil 80 % of the petroleum production is taken at sea and area of deployment and it cost scale are worrisome. It is associated, oily water production on a large scale, carrier 95% of the potential pollutant of activity whose final destination is the environment medium, terrestrial or maritime. Although diversified set of techniques and water treatment systems are in use or research, we propose an innovative system that operates in a sustainable way without chemical additives, for the good of the ecosystem. Labyrinth adsor-bent is used in metal spirals, and laboratory scale flow. Equipment and process patents are claimed. Treatments were performed at different flow rates and bands often monitored with control systems, some built, other bought for this purpose. Measurements of the levels of oil and grease (OGC) of efluents treaty remained within the range of legal framework under test conditions. Adsorbents were weighed before and after treatment for obtaining oil impregna-tion, the performance goal of vibratory action and treatment as a whole. Treatment technolo-gies in course are referenced, to compare performance, qualitatively and quantitatively. The vibration energy consumption is faced with and without conventional flotation and self-flotation. There are good prospects for the proposed, especially in reducing the residence time, by capillary action system. The impregnation dimensionless parameter was created and confronted with consecrated dimensionless parameters, on the vibrational version, such as Weber number and Froude number in quadratic form, referred to as vibrational criticality. Re-sults suggest limits to the vibration intensity
Um prot?tipo vibr?til autoflotador de acionamento eletromec?nico para tratamento de ?gua de produ??o de petr?leo e emuls?o cong?nere ? apresentado e avaliado. A produ??o de petr?leo para refinamento e obten??o de derivados ? realizada sob modalidades tecnicamente referidas como on-shore e off-shore, isto ?, no continente e no mar. No Brasil 80% da produ??o petrol?-fera ? feita no mar e ?rea de implanta??o e escala de custo s?o preocupantes. Associa-se ?gua oleosa de produ??o, efluente abundante em larga escala, carreadora de 95% do potencial polu-idor da atividade cujo destino final ? o meio ambiente mar?timo ou terrestre. Embora diversi-ficado conjunto de t?cnicas e sistemas de tratamento d ?gua encontram-se em uso ou pesqui-sa, prop?e-se um sistema inovador que opera de forma sustent?vel sem aditivos qu?micos, pa-ra o bem do ecossistema. Utilizou-se labirinto adsorvente, em espirais met?licos, e escala la-boratorial de fluxo. Patentes de equipamento e processo s?o reivindicadas. Realizaram-se tra-tamentos em vaz?es e faixas de frequ?ncia distintas, monitoradas com sistemas de controle, uns constru?dos, outros aquistados para tal. Medi??es do teor de ?leo e graxa (TOG) do eflu-ente tratado mantiveram-se dentro do intervalo de enquadramento legal nas condi??es de en-saio. Pesaram-se os adsorventes antes e ap?s o tratamento para obten??o da impregna??o de ?leo, meta de desempenho da a??o vibrat?ria e tratamento como um todo. Tecnologias atuais de tratamento s?o referenciadas para compara??o de desempenho, qualitativa e quantitativa-mente. Confrontou-se consumo energ?tico operando-se em vibra??o, com e sem flota??o con-vencional, e com autoflota??o. Vislumbram-se boas perspectivas de rendimento do sistema proposto, sobretudo, na redu??o do tempo de resid?ncia por a??o de capilaridade. Criou-se o par?metro adimensional de impregna??o e se lhe confrontou com consagrados par?metros a-dimensionais, na vers?o vibracional, como n?mero de Weber e n?mero de Froud quadr?tico, referido como criticalidade vibr?til. Resultados sugerem limites ? intensidade vibrat?ria

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Rodrigues, Ciro Jos? Ferreira. "Estudo da efic?cia do tensoativo sorbitano tween 80 veiculado em nanoemuls?o contendo ?leo de soja, como inibidor de corros?o." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/17700.

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Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
Nowadays, the use of chemicals that satisfactorily meet the needs of different sectors of the chemical industry is linked to the consumption of biodegradable materials. In this context, this work contemplated biotechnological aspects with the objective of developing a more environmentally-friendly corrosion inhibitor. In order to achieve this goal, nanoemulsion-type systems (NE) were obtained by varying the amount of Tween 80 (9 to 85 ppm) a sortitan surfactant named polyoxyethylene (20) monooleate. This NE-system was analyzed using phase diagrams in which the percentage of the oil phase (commercial soybean oil, codenamed as OS) was kept constant. By changing the amount of Tween 80, several polar NE-OS derived systems (O/W-type nanoemulsion) were obtained and characterized through light scattering, conductivity and pH, and further subjected to electrochemical studies. The interfacial behavior of these NE-OS derived systems (codenamed NE-OS1, S2, S3, S4 and S5) as corrosion inhibitors on carbon steel AISI 1020 in saline media (NaCl 3.5%) were evaluated by measurement of Open Circuit Potential (OCP), Polarization Curves (Tafel extrapolation method) and Electrochemical Impedance Spectroscopy (EIS). The analyzed NE-OS1 and NE-OS2 systems were found to be mixed inhibitors with quantitative efficacy (98.6% - 99.7%) for concentrations of Tween 80 ranging between 9 and 85 ppm. According to the EIS technique, maximum corrosion efficiency was observed for some tested NE-OS samples. Additionaly to the electrochemical studies, Analysis of Variance (ANOVA) and Principal Component Analysis (PCA) were used, characterization of the nanoemulsion tested systems and adsorption studies, respectively, which confirmed the results observed in the experimental analyses using diluted NE-OS samples in lower concentrations of Tween 80 (0.5 1.75 ppm)
Atualmente, a utiliza??o de produtos qu?micos que atendam satisfatoriamente as necessidades de diferentes setores da ind?stria qu?mica encontra-se vinculada ao consumo de materiais biodegrad?veis. Neste contexto, o presente trabalho foi desenvolvido contemplando aspectos biotecnol?gicos com o objetivo de se desenvolver um inibidor de corros?o menos agressivo ao meio ambiente. Para tanto, uma nanoemuls?o (denominada de NE-OS) foi obtida com Tween 80 (polioxietileno (20) monooleato), ?leo de soja (OS) e ?gua bidestilada. A modifica??o dos percentuais deste tensoativo sorbitano (entre 9 e 85 ppm) foi avaliada em diagramas de fases em que se manteve constante o percentual da fase ?leo, possibilitando a forma??o do sistema NE-OS em diferentes concentra??es. Desta forma, nanoemuls?es (NE-OS1, S2, S3, S4 e S5) polares (do tipo O/A) foram caracterizadas (an?lise de dispers?o de luz, condutividade e pH) e submetidas a estudos eletroqu?micos. O comportamento interfacial destes sistemas nanoemulsionados como inibidores de corros?o na presen?a de a?o-carbono AISI 1020, em meio salino (NaCl 3,5%) foi avaliado pela determina??o do Potencial de Circuito Aberto (OCP), Curvas de Polariza??o (obtidas pela extrapola??o das curvas de Tafel) e Espectroscopia de Imped?ncia Eletroqu?mica (EIE). De acordo com os resultados obtidos pelas an?lises das Curvas de Polariza??o, foi poss?vel caracterizar o sistema NE-OS (e suas varia??es) como inibidores mistos com efici?ncias m?ximas de inibi??es quantitativas (98,6% - 99,7%) para NE-OS1 e NE-OS2 (9 - 85 ppm do tensoativo). No entanto, de acordo com a t?cnica EIE, as efici?ncias m?ximas de inibi??es quantitativas foram observadas para v?rias amostras deste sistema NE-OS. Como ferramentas adicionais aos estudos eletroqu?micos foram realizados quimiom?tricos de An?lise de Vari?ncia (ANOVA) e An?lise de Componentes Principais (PCA), utilizadas, respectivamente, para caracteriza??o das nanoemuls?es e estudo de isotermas de adsor??o, que confirmaram os resultados observados nas investiga??es experimentais em que se utilizaram as nanoemuls?es dilu?das com o tensoativo em concentra??es reduzidas (0,5 1,75 ppm)

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Huang, Shin-Lun, and 黃士倫. "Investigation of Relationships among Prices of Crude Oil, Rubber, and Listed Rubber-Related Stocks." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/30849581238552136207.

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碩士
國立臺灣大學
農業經濟學研究所
103
The products from the rubber industry are extensive usage in life due to their functionality. Nevertheless, the raw materials of rubber products come from both natural rubber and synthetic rubber derived from petrochemical materials of crude oil. As a result, domestic rubber producers have to face the price fluctuation from those mentioned above. The purpose of this study is to investigate relationships among prices of crude oil, rubber, and listed rubber-related stocks from January 2010 to December 2014. The samples include the price of natural rubber and three kinds of prices in crude oil, and listed rubber-related stocks in Taiwan. The methodology applied consists of descriptive statistics, unit root test, cointegration test and error correction model for investigating the trend, the short-term and long-term relationships among these prices. The results found in the study are as follows. First, the price of Hwa Fong Rubber among 9 firms is the only one which did not have significant correlation relationship with prices of crude oil and natural rubber based on the trend chart. Second, the unit root test found that all the prices become stationary through first order difference. Third, the cointegration test reveals that although the price of Hwa Fong Rubber is the only one that did not exist the long-term relationships with those of crude oil and natural rubber, all the stock price series shows positive relationships with them. Finally, the empirical result of the short-term adjustment coefficients in error correction model found that all the adjustment coefficients of stocks are quite significant besides Hwa Fong Rubber. In addition, the prices of crude oil and natural rubber in the short-term can obviously affect the prices of listed rubber-related stocks and these stock prices converge gradually and slowly to the long-run equilibrium.

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Galbraith, Patricia Rosemary. "An analysis of disclosures prepared by listed entities undertaking mining or oil and gas activities." Thesis, 2015. http://hdl.handle.net/10539/18848.

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Thesis (M. Com. (Accountancy))--University of the Witwatersrand, Faculty of Commerce, Law and Management, School of Accountancy, 2015.
ABSTRACT The extractive activities industry includes entities that explore for, discover, develop and extract deposits of minerals, oil and natural gases. Recent research conducted has concluded that accounting for the assets and expenditure together with the disclosure requirements in this industry are not comprehensively addressed by current International Financial Reporting Standards (IFRS). The debate surrounding the accounting and disclosure alternatives in the industry as well as movements to standardise them have been ongoing since the 1890s. The latest movement by the International Accounting Standards Board (IASB) resulted in a project team publishing the Discussion Paper DP/2010/1 – Extractive Activities of April 2010 (Discussion Paper). The Discussion Paper presents disclosures determined to provide the most useful information to the users of the industries financial statements. The IASB have paused this topic and it will not be added to the agenda in the near future, however, this Discussion Paper is likely to form the foundation of a new IFRS. This research report will assess how the reserves and related disclosures currently prepared by entities in the mining or oil and gas industry compare to the proposed disclosure requirements of the Discussion Paper. This research report uses a mixed methodology. Quantitative analysis, through the use of a disclosure checklist, dominates the study which covers two years. The results of this study are then qualitatively and compared per proposed disclosure, against market capitalisation, by listing sector, by external auditor and whether the entity has a single or a dual-listing. Overall the study shows that the current disclosures of the entities do not satisfy the proposed disclosures of the Discussion Paper. Entities in the extractive activities industry would need to invest more into financial reporting in order to achieve compliance with the disclosures should they ever form part of an IFRS. The findings do indicate that the number of disclosures provided is dependent on the size of the entity. The two entities PRG/0500709A i found to have the most disclosures are in the gold mining sector and have an alternative listing on the New York Stock Exchange.

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Lin, Wen-chi, and 林雯琪. "The Impact of Crude Oil Price Change on Stock Returns: Evidence form Taiwan Listed Companies." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/34539251290661577427.

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碩士
南華大學
財務金融學系財務管理碩士班
101
Oil is one of the major energy resources currently with its price fluctuation remarkably affecting the economy and politics of every nation around the world. Because we heavily depend on imported oil, the soaring oil prices on international markets recently cause a severe issue to the overall economy of Taiwan. The soaring oil prices have added our financial burden to badly impede our export competitiveness due to cost-up pressure with revenue reduced among local business organizations. Therefore, the fluctuation of the oil prices on international markets is quite an issue worthy of our emphasis. 　　　This study was based on the Multi-factor Market Model proposed by Sadorsky (2001) to explore the influence on the investment return of stock prices caused by the fluctuation of oil prices during the period from 2001 to 2012. In this article, the data collected from the industries separately of shipping, plastic, LED, architecture & construction and banking on the public stock market listed in the Taiwan Stock Exchange Corporation for empirical analysis. It was hoped through cross-industrial comparisons, it was available to delineate the practical influence on the stock prices of the corporations from different industries exerted by the fluctuation of oil prices. This study was conducted by using two major variables, namely the factors of the overall economic side (change rates of oil prices, market excess return, interest spreads and exchange rates) and the individual characteristics of corporations (volume, P/B ratios, revenue and earning ratios). 　　　The empirical results show that for those corporations viewing petroleum as important raw material, the changes happening to oil prices exerted significantly positive influence on stock prices. Other industries showed a remarkable variance because different models were set different models. The investment return on stocks were also affected by the characteristics of different corporations separately.

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HSU, WEN-AN, and 許文安. "The Relationship Between Crude Oil Price, Baltic Dry Index and the Stock Prices of Maritime Listed Companies in Taiwan." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/6kfx6m.

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碩士
南華大學
財務金融學系財務管理碩士班
107
Taiwan is an island-type country and its geographical position has an important position in military, transportation and trade, and it has a considerable degree of dependence on the shipping industry regardless of whether it is imported or exported. However, the price of crude oil has changed drastically in recent years. For maritime operators whose fuel accounts for about 18% to 20% of the cost, the control of fuel cost is undoubtedly a challenge. In addition, the rise and fall of BDI will affect the income of the maritime industry, which can be said to be the economic indicator of the maritime industry. 　　The research price of Brent crude oil, BDI index, 9 Taiwan shipping industry (Evergreen Marine, Sincere Navigation, U-Ming, Yang Ming, CMT, China Container, Wanhai, Taiwan Navigation, Shih Wei Navigation) was held on July 3, 2001. The data of the day, week and month of October 31, 2018 are the research objects. Through the VAR model analysis, the causal relationship and mutual influence of Brent crude oil price, BDI index and the stock price of 9 Taiwan shipping companies are discussed. The study found that the crude oil price is a one-way relationship with the BDI index. The BDI index and the maritime industry share price are mainly based on bulk shipping. The relationship between crude oil price and the shipping stock price is mostly single. To the relationship, but if the VAR model analysis is constructed from the data of the three, the relationship becomes more complicated.

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Nienaber, Hester. "Market strategies applied by selected JSE-listed SA food manufacturers (major group meat, fish, fruit, vegetables, oils and fats) in the period 1996 to 1999: an exploratory study." Thesis, 2002. http://hdl.handle.net/10500/1568.

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The observation that similar firms faced with a similar situation and seemingly applying similar market strategies and achieving differing degrees of success sparked the study. The question that arose was whether the market strategies applied by these firms adhered to the principles of a sound market strategy put forward in the literature. The study found that the market strategy applied by the firms in question complied with the principles of market strategy, to varying degrees. The firms that adhered to these principles to a greater degree appeared to have been more successful than the others. It appeared that the latter firms neglected the principle "sustainable competitive advantage''. It was concluded that the adherence to the principles of a sound market strategy could lead to improved performance.
Business Management
D. Comm. (Business Management)

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