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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Performance of horizontal wells /

Ozkan, Erdal. January 1988 (has links)
Thesis (Ph.D.)--University of Tulsa, 1988. / Includes bibliographical references.
102

Improved oil recovery by sequential waterflooding and by injection of low salinity brine

Loahardjo, Nina. January 2009 (has links)
Thesis (Ph.D.)--University of Wyoming, 2009. / Title from PDF title page (viewed on June 10, 2010). Includes bibliographical references.
103

A comprehensive skin factor model for well completions based on finite element simulations

Furui, Kenji. Hill, A. D. January 2004 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisor: A. Daniel Hill. Vita. Includes bibliographical references.
104

EFFECTS OF STEARIDONIC ACID-ENRICHED SOYBEAN OIL ON METABOLIC PROFILE AND FATTY ACID COMPOSITION IN LEAN AND OBESE ZUCKER RATS

Casey, John 01 December 2013 (has links)
Background, Consumption of marine-based oils high in omega-3 polyunsaturated fatty acids (n3PUFAs), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) is known to protect against obesity-related pathologies. It is less clear whether traditional vegetable oils with high omega-6 polyunsaturated fatty acid (n6PUFA) content exhibit similar therapeutic benefits. As such, this study examined the metabolic effects of a plant-based n3PUFA, stearidonic acid (SDA), in polygenic obese rodents. Methods, Lean (LZR) and obese Zucker (OZR) rats were provided either a standard westernized control diet (CON) with a high n6PUFA to n3PUFA ratio (i.e., 16.2/1.0) or experimental diet modified with flaxseed (FLAX), menhaden (FISH), or SDA oil that resulted in n6PUFA to n3PUFA ratios of 1.7/1.0, 1.3/1.0, and 1.0/0.8, respectively. Results, After 12 weeks, total adiposity, dyslipidemia, glucose intolerance, and hepatic steatosis were all greater, whereas n3PUFA content in liver, adipose, and muscle was lower in OZR vs. LZR rats. Obese rodents fed modified FISH or SDA diets had lower serum lipids and hepatic fat content vs. CON. The omega-3 index (i.e., ÓEPA + DHA in erythrocyte membrane) was 4.0, 2.4, and 2.0-fold greater in rodents provided FISH, SDA, and FLAX vs. CON diet, irrespective of genotype. Total hepatic n3PUFA and DHA was highest in rats fed FISH, whereas both hepatic and extra-hepatic EPA was higher with FISH and SDA groups. Conclusions, these data indicate that SDA oil represents a viable plant-derived source of n3PUFA, which has therapeutic implications for several obesity-related pathologies.
105

Renda petrolífera: geração e apropriação nos modelos de organização da indústria brasileira / OIL RENT: GENERATION AND APPROPIATION IN THE ORGANIZATIONAL MODEL OF BRAZILIAN OIL INDUSTRY

Lizett Paola López Suárez 20 December 2012 (has links)
Esta tese teve como objetivo analisar o processo de geração e apropriação da renda petrolífera nos modelos de organização adotados pela indústria brasileira de petróleo. O interesse pelas jazidas de petróleo tem sua origem nas altas rendas geradas na cadeia produtiva, principalmente na fase de exploração, as quais podem ser apropriadas por quem exerce a propriedade sobre o recurso. O entendimento da moderna indústria petrolífera brasileira em um contexto de altos preços de petróleo, de incremento da produção e da descoberta de grandes acumulações de petróleo no pré-sal, leva à discussão em torno da disputa da riqueza gerada, o modelo de organização da indústria e o papel da empresa estatal, PETROBRAS. Tais aspectos foram avaliados seguindo uma perspectiva histórica, baseada no estudo da renda marxista e na aplicação de categorias concretas de análise à indústria petrolífera, abrangendo no período de estudo o pré-monopólio do petróleo, a consolidação da indústria petrolífera com bases estatais, o modelo de concessão e o modelo misto para explorar o pré-sal. A indústria petrolífera mexicana e venezuelana foram estudadas como referencia. Realizada a análise, identificou-se - dada a disponibilidade de recursos petrolíferos orientados a atender o abastecimento interno - o predomínio de excedente econômico gerado no mercado nacional e em menor medida uma renda petrolífera, diferencial e absoluta conseguida no mercado internacional. Também se constatou que dentro do estado nacional moldou-se um processo de disputa do excedente econômico nas suas várias etapas históricas, já que, uma vez definida a hegemonia sobre o petróleo, a disputa pelos excedentes se dá no seio do próprio Estado, entre os estados e os municípios. Concluiu-se que o modelo de organização da indústria petrolífera brasileira é resultado da disputa pelas forças envolvidas na apropriação da renda petrolífera. / This thesis aims to analyze the process of generation and appropriation of oil rent in the organizational models adopted by the Brazilian oil industry. Interest in owning of petroleum fields has its origin in the high rents generated in the production chain, especially in the exploration phase, which may be appropriated by whoever has the property rights on the resource. The understanding of modern Brazilian oil industry in a context of high oil prices; the increase of production and the discovery of large accumulations of oil in pre-salt, leads to discussions around the dispute of the wealth generated, the organizational model of the industry and the role of state-owned company, PETROBRAS. These aspects were evaluated following a historical perspective, based on the study of Marxist rent theory and the application of concrete categories of analysis specific to the oil industry, covering in the period of the study the pre-monopoly, the consolidation of the oil industry with state basis, the concession model and the mixed model to explore the pre-salt. Given the availability of oil resources geared to meet domestic supply during the analysis it was identified the predominance of economic surplus generated in the domestic market and to a lesser extent, a differential and absolute rent achieved in the international market. On the other hand, also within the national state a process of dispute of that economic surplus was shaped, once defined hegemony over oil the dispute for economic surpluses occurs within the state itself, between the states and municipalities. It was concluded that the organizational model of Brazilian oil industry is a result of the dispute by the forces involved in the appropriation of oil rents.
106

Analýza faktorů ovlivňujících trh s ropou / Analysis of factors affecting the oil market

Joneš, Pavel January 2008 (has links)
Oil is currently one of the most used energy sources on earth because enters into almost all goods and services. A number of economy and households is dependent on oil. In recent years a trend in the oil market raises many questions. The scope of this diploma thesis is to identify and to analyze key factors influencing the oil market. The next aim is to predict future development of this market. The analysis is focused on the most important economic, geopolitical, environmental and technological factors affecting the oil market. Methodology of the thesis is based on the literature research and on the basic statistical methods to analyze the factors and estimate the future of the oil market.
107

Numerical analysis of thermal enhanced oil recovery methods

Youtsos, Michael Spiro January 2014 (has links)
No description available.
108

Temperature insensitive microemulsions

Taylor, Diana Jacqueline Falcon January 1999 (has links)
No description available.
109

Modelling and evaluating petroleum migration pathways in the Paris, Williston and West of Shetlands and Wessex Basins

Hindle, Andrew D. January 1998 (has links)
Petroleum migration pathways through a basin are determined by the three-dimensional distribution of discontinuous sealing surfaces, which are usually parallel to bedding. The petroleum migrates below the sealing surface taking the structurally most advantageous route. The three-dimensional distribution of migration pathways within the petroleum system can be modelled on a personal computer using a program based on the parameters developed during the research summarised in this thesis. Application of the model to the Paris, Williston, West of Shetlands and Wessex Basins demonstrates that a good correlation can be made between predicted pathways and discovered accumulations using simple models. Migration pathways form a dense network overlying hydrocarbon generating areas in the central parts of basins. Towards the basin margins they commonly become increasingly focused into discrete pathways by the sealing-surface morphologies. The Paris and Williston Basin research showed how relatively minor structuring of geological strata can result in a significant focusing of pathways. Eventually these pathways may reach the surface as shown by seepages. Research in the Wessex Basin revealed that reverse modelling of pathways from seeps assists in the prediction of the location of leaking accumulations. Deflection of the pathways from the structurally most advantageous route below the sealing surface may be caused by lateral sealing barriers due to facies variation in the carrier rock below the seal, fault juxtaposition, or cross-formational seals such as salt intrusions. Deflection of pathways also occurs where there are hydrodynamic conditions in response to topography-driven groundwater flow.
110

Oil recovery by spontaneous imbibition for a wide range of viscosity ratios

Fischer, Herbert. January 2006 (has links)
Thesis (Ph. D.)--University of Wyoming, 2006. / Title from PDF title page (viewed on Dec. 20, 2007). Includes bibliographical references (p. 208-216).

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