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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.
71

Crude Oil and Crude Oil Derivatives Transactions by Oil and Gas Producers.

Xu, He 12 1900 (has links)
This study attempts to resolve two important issues. First, it investigates the diversification benefit of crude oil for equities. Second, it examines whether or not crude oil derivatives transactions by oil and gas producers can change shareholders' wealth. With these two major goals in mind, I study the risk and return profile of crude oil, the value effect of crude oil derivatives transactions, and the systematic risk exposure effect of crude oil derivatives transactions. In contrast with previous studies, this study applies the Goldman Sachs Commodity Index (GSCI) methodology to measure the risk and return profile of crude oil. The results show that crude oil is negatively correlated with stocks so adding crude oil into a portfolio with equities can provide significant diversification benefits for the portfolio. Given the diversification benefit of crude oil mixed with equities, this study then examines the value effect of crude oil derivatives transactions by oil and gas producers. Differing from traditional corporate risk management literature, this study examines corporate derivatives transactions from the shareholders' portfolio perspective. The results show that crude oil derivatives transactions by oil and gas producers do impact value. If oil and gas producing companies stop shorting crude oil derivatives contracts, company stock prices increase significantly. In contrast, if oil and gas producing companies start shorting crude oil derivatives contracts, stock prices drop marginally significantly. Thus, hedging by producers is not necessarily good. This paper, however, finds that changes in policy regarding crude oil derivatives transactions cannot significantly affect the beta of shareholders' portfolios. The value effect, therefore, cannot be attributed to any systematic risk exposure change of shareholders' portfolios. Market completeness, transaction costs, and economies of scale are identified as possible sources of value effect. The following conclusions have been obtained in this study. Crude oil provides significant diversification benefits for equities. In the presence of market imperfections, crude oil derivatives transactions by oil and gas producers may change shareholders' wealth, even though crude oil derivatives transactions by oil and gas producers do not have significant effect on the systematic risk exposures of companies.
72

Emergency oil system and international cooperation

Lee, Joonbeom, January 2001 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references (leaves 206-217). Also available on the Internet.
73

Emergency oil system and international cooperation /

Lee, Joonbeom, January 2001 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references (leaves 206-217). Also available on the Internet.
74

Transaction costs and choice of petroleum contract

Wirote Manopimoke January 1989 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1989. / Includes bibliographical references (leaves [127]-130). / Microfiche. / ix, 130 leaves, bound ill. 29 cm
75

Dynamic analysis in productivity, oil shock, and recession

Katayama, Munechika, January 2008 (has links)
Thesis (Ph. D.)--University of California, San Diego, 2008. / Title from first page of PDF file (viewed September 3, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 98-104).
76

Water spray suppression and intensification of high flash point hydrocarbon pool fires

Ho, San-Ping. January 2003 (has links)
Thesis (Ph. D.)--Worcester Polytechnic Institute. / Keywords: suppression; drop size; high flash point pool fire. Includes bibliographical references (p. 210-218).
77

Inventories, oil shocks, and aggregate economic behavior /

Herrera, Ana María. January 2000 (has links)
Thesis (Ph. D.)--University of California, San Diego, 2000. / Vita. Includes bibliographical references.
78

Alternative methods of oil supply forecasting

Adelman, Morris Albert., Jacoby, Henry D. January 1977 (has links)
This paper represents a collective effort by the Supply Analysis Group of the M.I.T. World Oil Project. / The Project is supported by the National Science Foundation under Grant no. SIA75-00739
79

Determinação de compostos carbonilados e carboxilados em derivados de petróleo

Vieira, Fernanda Seabra Vianna 16 September 2011 (has links)
Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2016-08-31T14:06:01Z No. of bitstreams: 1 Tese_Fernanda_Revisão Final.pdf: 5433077 bytes, checksum: 30cfa44a7a7312cf3778c6606c92d4ff (MD5) / Approved for entry into archive by Vanessa Reis (vanessa.jamile@ufba.br) on 2016-09-02T16:14:00Z (GMT) No. of bitstreams: 1 Tese_Fernanda_Revisão Final.pdf: 5433077 bytes, checksum: 30cfa44a7a7312cf3778c6606c92d4ff (MD5) / Made available in DSpace on 2016-09-02T16:14:00Z (GMT). No. of bitstreams: 1 Tese_Fernanda_Revisão Final.pdf: 5433077 bytes, checksum: 30cfa44a7a7312cf3778c6606c92d4ff (MD5) / Braskem / A nafta e o etanol são matérias-primas importantes da indústria petro e alcoolquímica respectivamente, tendo o eteno e o propeno como seus principais derivados da primeira geração. A eficiência desses processos produtivos pode ser comprometida por traços de compostos carbonílicos e carboxílicos voláteis neles contidos. Tal contaminação pode afetar, por exemplo, a qualidade de embalagens de alimentos, uma vez que tais derivados são compostos precursores para produção dos plásticos utilizados nessas embalagens. No presente trabalho foram desenvolvidos métodos simples para a determinação de compostos carbonílicos e carboxílicos em matrizes líquidas e gasosas derivadas do petróleo por cromatografia em fase gasosa com sistema de detecção por ionização em chama (CG/DIC), cromatografia líquida de alta eficiência (CLAE), cromatografia gasosa acoplada à espectrometria de massas (CG/EM) e CG/DIC acoplado a sistema analítico Dean Switch. Para a determinação dos ácidos acético, propanóico, butanóico e pentanóico em matrizes líquidas e gasosas, a cromatografia em fase gasosa com sistema de detecção por ionização em chama por injeção direta utilizando coluna cromatográfica capilar FFAP (for free fatty acids) foi a técnica mais adequada. O desvio padrão relativo (RSD) obtido foi de 5,6% a 6,5% para 2 g.g-1 em n-hexano, 2,1% a 5,8% para 10 g.g-1 em etanol e 4,2 a 7,7% para 10 g.g-1 em propeno. Os limites de detecção encontrados foram de 0,036 - 0,12 g.g-1 em hidrocarbonetos gasosos (eteno e propeno), 0,047 - 0,16 g.g-1 em matrizes puras de hidrocarbonetos líquidos (n-hexano) e 0,08 – 0,18g.g-1 em matriz alcoólica (etanol). Para a determinação do teor de ácidos carboxílicos em matrizes complexas como a nafta, a CLAE foi a técnica utilizada, precedida de extração líquido- Fernanda Seabra Vianna Vieira 11/238 líquido sob condições controladas. O RSD obtido foi de 5,5% a 7,7% para 40 g.g-1 e o limite de detecção médio foi de 4 g.g-1. Para a determinação dos teores dos compostos carbonílicos (aldeídos e cetonas) em matrizes líquidas e gasosas, a cromatografia empregando o sistema analítico comercial Dean Switch mostrou-se como a mais adequada. Valores de RSD da ordem de 2,6% a 3,5% para propeno; 0,9% a 1,4% para n-hexano e 1,6% a 2,6% para a nafta em padrões contendo respectivamente 2 g.g-1, 2 g.g-1 e 10 g.g-1. Os limites de detecção de 0,033 - 0,084 g.g-1 (propeno), 0,021- 0,09 g.g-1 (n-hexano) e 0,049 - 0,26 g.g-1 (nafta) confirmam a eficiência de detecção e quantificação para matrizes de hidrocarbonetos de origem petroquímica tipicamente inferiores a 10 g.g-1. A partir dos resultados obtidos foi feita uma avaliação comparativa entre as técnicas, evidenciando as vantagens e desvantagens de cada método para cada aplicação específica. / Although metals and nitrogen & sulfur compounds have been the main concern in the petroleum industry, issues on the harmful effects on catalysts poisoning and products contamination of other contaminants such as oxygen- containing compounds have been raised. Trace amounts of carbonyl and carboxyl compounds in petroleum products can lead to catalyst poisoning and overall decrease on reactions yield. Furthermore, oxygenates may be present in the polyethylene and polypropylene resins, affecting the quality of the food packagings obtained from these materials. The available literature on C1-C5 aldehydes, ketones and carboxylic acids determination in petroleum products such as naphtha, ethylene and propylene is quite rare. Therefore, in the present work we intend to review the analytical approaches that could be applied to such analytical purpose, present the features of each potential technique and some studies performed on somewhat similar matrices. For acetic, propanoic, butanoic and pentanoic acids determination in liquid and gas matrices, gas chromatography with flame ionization detector and FFAP for free fatty acids capillary column was the most appropriate method. The relative standard deviation (RSD) was 5.6% to 6.5% in the range of 2 g.g-1 in n-hexane, 2.1% to 5.8% in the range of 10 g.g-1 in ethanol and 4.2 to 7.7% in the range of 10 g.g-1 in propylene. The detection limits found were from 0.036 to 0.12 g.g-1 in hydrocarbons gases (ethylene and propylene), 0.047 to 0.16 g.g-1 in pure liquid hydrocarbons (n-hexane) and 0.08 to 0.18 g.g-1 in alcoholic matrices (ethanol). For carboxylic acid determination in complex matrices such as naphtha, the HPLC technique was used, preceded by liquid-liquid extraction under Fernanda Seabra Vianna Vieira 9/238 controlled conditions. The RSD obtained was 5.5% to 7.7% in the range of 40 g.g-1 within the average detection limit was 4 g.g-1. For carbonyl compounds (aldehydes and ketones) determination in gas and liquid matrices, the commercial analytical system Dean Switch proved to be the most appropriate. RSD values of around 2.6% to 3.5% for propylene; 0.9% to 1.4% for n-hexane and 1.6% to 2.6% for naphta in standards containing respectively 2 g.g-1, 2 g.g-1 and 10 g.g-1. The detection limit of 0.033 to 0.084 g.g-1 (propylene), 0.021 to 0.09 g.g-1 (n-hexane) and 0.049 to 0.26 g.g-1 (naphtha) confirm the efficiency of detection and quantification for range of hydrocarbons of petrochemical origin typically less than 10 g.g-1.
80

Produção, caracterização e aplicação de biossurfactante produzido por Mucor circinelloides UCP/WFCC 0001

Nathália Sa Alencar do Amaral Marques 03 May 2017 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Biossurfactantes são metabólitos secundários de origem microbiana com propriedades tensoativas capazes de atuar como solubilizantes, dispersantes, formadores de espuma e agentes molhantes. Surfactantes de origem biológica são mais vantajosos do que os sintéticos, visto que exibem pouca toxicidade, biodegradabilidade e alta eficiência. Os surfactantes de origem biológica podem ser classificadas de acordo com alguns critérios como, por exemplo, seu peso molecular, carga iônica e tipo de secreção. Contudo, o princípio fundamental de classificação continua a ser a sua estrutura química, o que lhes permite ser divididos nas seguintes classes: glicolipídicos, lipopeptídicos, surfactantes particulares, ácidos graxos, fosfolipídios, lipídios neutros e biossurfactantes poliméricos. Essas biomoléculas possuem uma vasta gama de aplicações na indústria de alimentos, na agricultura, em couro, em cosméticos, na área têxtil, recuperação avançada do petróleo e na biorremediação. A contaminação de solos e águas subterrâneas por hidrocarbonetos tornou-se um foco de grande preocupação, a principal fonte destes poluentes provém de operações rotineiras de lavagem de navios, vazamentos de óleo no mar e, especialmente acidentes relacionados a exploração e transporte de petróleo. O uso de biossurfactante tornou-se uma ferramenta essencial na biorremediação de áreas impactadas por petróleo e seus derivados, estes hidrocarbonetos tornam-se mais acessíveis para degradação microbiana local quando tratados com agentes tensoativos. O biossurfactante lipopeptídico produzido por M. circinelloides apresentou atividade superficial de 26 mN/m relativamente estável em condições ambientais adversas, com uma CMC de 1,5% e rendimento de 6 g/L. O tensioativo exibiu semelhança aos surfactantes químicos por apresentar uma área de deslocamento de óleo de 50 cm2 em dispersão de água-óleo, bem como reduzir a viscosidade do óleo de 843,6 cP para 14,7 cP. Além disso, o biossurfactante foi capaz de recuperar 95,9% de óleo de motor adsorvido em uma amostra de solo argiloso, apresentando considerável potencial para uso em processos de biorremediação, especialmente na indústria de petróleo. / Biosurfactants are secondary metabolites of microbial origin with tensoactive properties capable of acting as solubilizers, dispersants, foaming agents and wetting agents. Surfactants of biological origin are more advantageous than synthetic ones, since they exhibit little toxicity, biodegradability and high efficiency. Surfactants of biological origin can be classified according to some criteria such as, for example, their molecular weight, ionic charge and type of secretion. However, the fundamental principle of classification remains their chemical structure, which allows them to be divided into the following classes: glycolipids, lipopeptides, particular surfactants, fatty acids, phospholipids, neutral lipids and polymeric biosurfactants. These biomolecules have a wide range of applications in the food industry, agriculture, leather, cosmetics, textiles, advanced oil recovery and bioremediation. Contamination of soils and groundwater by hydrocarbons has become a focus of major concern, most in developing countries, because of their wide environmental distribution, which can reach the ground, groundwater and air. Consequently, these toxic compounds are the leading causes of death from toxicity. However, the main source of hydrocarbons in the environment comes from routine shipwreck operations, oil leaks in the seabed and especially accidents related to the exploration and transportation of oil. The use of biosurfactant has become an essential tool in the bioremediation of areas impacted by oil and its derivatives, these hydrocarbons become more compatible for microbial degradation when treated with surfactants. The lipopeptide biosurfactant produced by M. circinelloides showed a relatively stable surface activity of 26 mN / m in adverse environmental conditions, with a CMC of 1.5% and yield of 6 g / L. The surfactant exhibited similarity to chemical surfactants by having a 50 cm2 oil displacement area in water-oil dispersion, as well as reducing the oil viscosity from 843.6 cP to 14.7 cP. The biosurfactant was able to recover 95.9% of adsorbed motor oil in a clayey soil sample, presenting considerable potential for use in bioremediation processes, especially in the petroleum industry.

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