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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.
31

Gasoline use control measures in cities and regions of the United States

Hamilton, Timothy Mitchell. January 1975 (has links)
Call number: LD2668 .P7 1975 H35
32

Hazard Assessment of Portable Gasoline Container Flammability

Elias, Brian 06 October 2011 (has links)
"This study considers the flammability hazard associated with the pouring of gasoline from a portable gasoline container (PGC) in an area containing a potential ignition source. In this scenario a flame may propagate into the PGC and cause an explosion if a flammable environment exists along the length of the pour spout and into the PGC headspace. In order to quantify this hazard, experiments are conducted to measure the flammable vapor concentration within this area under various conditions of temperature, liquid volume, and container pour angle. It is found that liquid fuel volumes as high as 30 mL in a 5-gallon PGC are capable of producing a flammable vapors within the PGC headspace. Finally, a mathematical model is presented to predict the flammability hazard under various conditions."
33

Método alternativo para detecção de não conformidade em gasolina comercial brasileira do tipo C /

Munhoz, João Fernando Villarrubia Lopes. January 2013 (has links)
Orientador: José Eduardo de Oliveira / Coorientador: Danilo Luiz Flumignan / Banca: Aristeu Gomes Tininis / Banca: Fabio da Silva Vinhado / Resumo: O Governo brasileiro intervia diretamente na comercialização de combustíveis até a década de 90. Com a abertura do mercado, pequenos revendedores sem contrato exclusivo com qualquer distribuidora, chamados de 'bandeiras brancas', surgiram no ambiente concorrencial. Com o propósito de assegurar a qualidade, a Agência Nacional do Petróleo, Gás Natural e Biocombustíveis, ANP, criou portarias especificando as características físico-químicas da gasolina comercial brasileira, tal como a Portaria nº 309. Com a crescente quantidade de informações, a diminuição do tempo de análise é uma necessidade. Uma técnica promissora é a cromatografia gasosa ultrarrápida, capaz de realizar uma corrida em poucos minutos, ou até mesmo em alguns segundos. Para isso, o comprimento da coluna capilar e seu diâmetro interno são reduzidos e seu aquecimento é feito através de uma resistência encapsulada. Assim, é possível obter os mesmos resultados em tempo diminuído e com a mesma qualidade. O aumento do volume de informações obtido experimentalmente exige ferramentas matemáticas mais avançadas para seu tratamento. Desde a década de 70, a quimiometria tem sido aplicada na obtenção, representação e transformação destes dados. O objetivo deste trabalho é criar um método de cromatografia gasosa ultrarrápida para análise de gasolinas comerciais brasileiras e, com ferramentas quimiométricas, classificar quanto à qualidade segundo a ANP. No desenvolvimento, cerca de 580 amostras de gasolinas comerciais foram coletadas mensalmente na região centro-oeste do estado de São Paulo. Os ensaios físico-químicos obtidos revelaram que grande parte não estava em conformidade com as portarias estabelecidas, possuindo apenas um parâmetro em discordância: a quantidade de etanol em sua composição... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Brazilian government intervened directly in the commercialization of fuel until de 90s. By opening of the marketing, small dealers without exclusive contract with any distributor, called 'white flags', appeared in the competitive environment. In order to ensure quality, the National Agency of Petroleum, Natural Gas and Biofuels, ANP, has created ordinances which specify physico-chemicals characteristics of Brazilian commercial gasoline, such as the Ordinance No 309. By increasing the amount of information, reducing the analysis time is a necessity. A promising technique is the ultra-fast gas chromatography, able to perform a chromatographic run in just few minutes, or even in seconds. Thereunto, the capillary column length and its internal diameter are reduced and its heating is done via an encapsulated resistor. It is possible to obtain the same results in reduced time and with the same quality. The increasing volume of information obtained experimentally requires more advanced mathematical tools for their treatment. Since the 70s, Chemometrics has been applied in acquisition, representation and processing these data. The objective of this work is to create an ultrafast gas chromatography method for analisys of the Brazilian commercial gasoline and, with chemometric tools, sort by their quality according to ANP. In development, about 580 commercial gasoline samples were collected monthly in the central-western state of São Paulo. The physico-chemical assays reveled that a great fraction of which was not in accordance with the ordinances established, having only one parameter in disagreement: the amount of ethanol in its composition. The addition of adulterants to some samples was necessary to increase the variability of the data. Monthly, 50 of 580 samples were selected by the hierarchical cluster analysis... (Complete abstract click electronic access below) / Mestre
34

Development of new and improved catalysts for the isomerisation of refinery products

Galadima, Ahmad January 2012 (has links)
As the recent environmental legislation highlights the risks associated with the use of gasoline additives such as octane enhancers, hydroisomerisation of n-alkanes in the gasoline feed to their corresponding isomers emerges as a key industrial alternative. Important catalysts have previously been tested and abandoned due to a number of problems including cost and poor resistance to catalyst poisons even in trace quantities. The current research evaluated the potentials of zirconia supported molybdenum carbide catalysts as replacements. The active carbided MoO3/ZrO2, MoO3/SO42- -ZrO2 and Rh/MoO3/ZrO2 have been prepared by in situ carburisation with CH4/H2 at 650oC and characterised by N2 adsorption, X-ray diffraction, X-ray photoelectron spectroscopy, Diffuse Reflectance Fourier Transformed Infrared spectroscopy, and temperature programmed reduction and oxidation. The characterisation data showed the carburisation process to proceed in a stepwise manner, involving the participation of hydrogen and methane as reducing and carbiding agents, respectively. Low (0.5 wt %) Rh loading and pre-treatment cycle via reduction and reoxidation significantly reduced the carburisation temperature, with the extent of the effect been dependent on the MoO3 loading. All of the catalysts produced showed stable activity and selectivity. Over the carbided MoO3/ZrO2, the activity was generally low at 450oC, producing mainly hydrogenolysis products. However, the activity of carbided MoO3/SO42- -ZrO2 at 350-450oC showed strong dependence on the nature of the n-alkane with reaction rates being lower for the higher alkanes. n-Nonane and n-octane produced mainly hydrocracking products whereas n-hexane and n-heptane were converted to the corresponding isomers with a very high selectivity. The catalyst forms a potential material for hydroisomerisation of gasoline range light paraffins. The 10 wt% Rh/MoO3/ZrO2 catalyst was more active to hydrogenolysis than with 25 wt% Rh/MoO3/ZrO2 under similar conditions due to higher activity of Rh species. However, the hydroisomerisation selectivity was highly favoured at lower temperatures, especially with n-hexane.
35

Competition in the Retail Gasoline Industry

Brewer, Jed January 2007 (has links)
This dissertation examines competition in the retail gasoline industry. The first chapter highlights the importance of gasoline in modern society, introduces my work, and places it in the context of the existing academic literature.The second chapter details the institutional structure and profitability of the industry. The vast majority of retail gasoline stations are not directly owned and operated by major oil companies. Instead, most stations are set up under other contractual relationships: lessee-dealer, open-dealer, jobber-owned-and-operated, and independent. Gasoline retailers make relatively low profits, as is the case in many other retail industries, and are substantially less profitable than major oil companies. Gas stations also make less money when retail prices are climbing than when they are falling. As prices rise, total station profits are near zero or negative. When retail prices are constant or falling, retailers can make positive profits.The third chapter describes the entry of big-box stores into the retail gasoline industry over the last decade. The growth of such large retailers, in all markets, has led to a great deal of controversy as smaller competitors with long-term ties to the local community have become less common. I estimate the price impact that big-box stores have on traditional gasoline retailers using cross-sectional data in two geographically diverse cities. I also examine changes in pricing following the entry of The Home Depot into a local retail gasoline market. The results show that big-box stores place statistically and economically significant downward pressure on the prices of nearby gas stations, offering a measure of the impact of the entry of a big-box store.Chapter 4 examines the nature of price competition in markets where some competing retailers sell the same brand. The price effect of having more retailers selling the same brand is theoretically unclear. High brand diversity could give individual retailers market power, thereby leading to higher prices. Low brand diversity, though, could act to facilitate collusive behavior, leading to higher prices. I find that prices are higher in markets with high brand diversity.The final chapter of the dissertation summarizes the general findings.
36

A comparison of propane and gasoline as fuels in an Otto cycle engine

Zeringue, Herman Jude 08 1900 (has links)
No description available.
37

Experimental and analytical comparisons of the performance and combustion characteristics of gasoline, methane, and methanol in a Wankel engine

Raut, Pravin Kamalakar 05 1900 (has links)
No description available.
38

An estimation of the demand for gasoline in Montana, and projections of future gasoline consumption

McNay, Aaron David. January 2008 (has links) (PDF)
Thesis (MS)--Montana State University--Bozeman, 2008. / Typescript. Chairperson, Graduate Committee: Douglas J. Young. Includes bibliographical references (leaves 57-64).
39

Essays on the effects of state and local public policy gasoline taxes, clean indoor air regulations, and gross receipts taxes /

Childs, Randy. January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains v, 98 p. Includes abstract. Includes bibliographical references (p. 95-98).
40

The effective volatility of motor fuels

Miller, Jarvis Elmer, Brown, George Granger, January 1930 (has links)
Thesis (Ph. D.)--University of Michigan, 1930. / Cover title. Caption title: Motor-fuel volatility. III--Effective volatility under driving-conditions [by] Jarvis E. Miller and George Granger Brown. Reprinted from Industrial and engineering chemistry, v. 22, June, 1930.

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