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Liquid fuel spray characteristicsSavic, Sasha January 2000 (has links)
No description available.
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The politics of Earth First! in the United KingdomWall, Derek January 1998 (has links)
No description available.
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Polymer electrolyte fuel cell diagnosticsBuche, Silvain January 1999 (has links)
No description available.
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Investigation of a novel solid oxide fuel cell interconnectWright, Emma Victoria January 1998 (has links)
No description available.
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Transverse flux machines for high torque applicationsMaddison, Christopher Paul January 1999 (has links)
Transverse Flux Machines (TFM) present some interesting problems to the machine designer, electro-magnetically and mechanically. They offer the lure of an extremely high specific output, but only, apparently, at the price of intricate three dimensional flux paths, a complicated construction and a low power factor. The research covered by this thesis was concerned with the study, development and improvement of these machines with a view to reducing the detracting aspects of the marque whilst accentuating its advantages. Extensive three dimensional finite element analysis into a wide range of TFM topologies, was coupled with practical investigations into three prototype TFMs constructed at Newcastle University. The result of this work was an improved TFM topology with comparatively good power factor, a simple single sided geometry and a very high specific output.
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Composite Zirconium Phosphate/PTFE Polymer Membranes for Application in Direct Hydrocarbon Fuel CellsAl-Othman, Amani Lutfi 30 April 2012 (has links)
Higher temperature (~ 200°C) operation for proton exchange membrane (PEM) fuel cells would have several advantages including enhanced electrochemical kinetics, useful heat recovery, and improved catalyst tolerance for contaminants. Conventional perfluorosulfonic acid membranes (PFSA), such as Nafion show a dramatic decrease in proton conductivity at temperatures above 80°C. For this reason, there has been an increasing effort toward the development of stable, higher temperature membranes with acceptable proton conductivity. This work is directed toward the development of Nafion free membranes for direct hydrocarbon PEM fuel cells containing zirconium phosphate as the proton conductor component. Hence, composite membranes composed of zirconium-phosphate (ZrP), a solid proton conductor, which was precipitated within the voids of a porous polytetraflouroethylene (PTFE) support were synthesized. Amorphous-like zirconium phosphate (ZrP) powder was synthesized in this work. ZrP was prepared by precipitation at room temperature via reaction of ZrOCl2 with H3PO4 aqueous solutions. The proton conduction properties of ZrP powder were studied under the processing conditions found in direct hydrocarbon fuel cell. Our experimental results showed that the ZrP powder processed at 200°C possess a proton conductivity that is greater by one order of magnitude than the oven-dried samples at 70°C. Thereby, it was possible to avoid the normal decrease in conductivity with increasing temperature by having sufficient water in the vapor phase. This thesis reports the first synthesis of composite ZrP/PTFE/Glycerol (GLY) membranes. Glycerol (GLY) was introduced into the pores of PTFE with the ZrP proton conductive material using the successive wetting/drying technique. These membranes had reasonable values of proton conductivities (0.045 S cm-1), approaching that of Nafion (0.1 S cm-1) at room temperature. Samples of these composite membranes were processed at the inlet conditions of a propane fuel cell, at 200°C. Experimental results showed that the proton conductivity remained almost unchanged. This thesis also describes and reports the first synthesis of sulphur “S” or silicon, Si–modified zirconium phosphate (ZrP), porous polytetrafluoethylene (PTFE) and, glycerol (GLY) composite membranes. It was aimed at the substitution of a minor amount of phosphorus “P” in the ZrP by (S or Si) in the ZrP to modify the proton conduction properties. The modification was performed by adding a certain amount of silicic acid or sulphuric acid into phosphoric acid then proceeding with the precipitation in situ. A high proton conductivity, of 0.073 S cm-1,i.e. 73% of that of Nafion, was observed for the Si–ZrP/PTFE/GLY composite membrane.
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Direct Chill Casting of Aluminum Alloys: Experimental Methods and DesignNg, Harry 19 January 2011 (has links)
Novelis Global Technology Centre (NGTC) in Kingston, Ontario have been developing a relatively new technology known as Novelis Fusion™ Technology, which is a new variant of the traditional direct chill (DC) casting process that allows co-casting of multi-layered composite aluminum alloy ingots. One of the first steps in this development program is to create a mathematical model of conventional DC casting and validate it through experimentation before proceeding to the next step of modeling, designing, testing, and experimenting with the co casting process. The focus of this document is on the design of the experiments, measurement technique, and analysis of the experimental results to be used to validate the models for conventional DC casting. A series of experiments was conducted using a lab scale caster using a 95 mm × 227 mm rectangular mould available at the Novelis Global Technology Centre in Kingston, Ontario. AA3003, AA6111, and AA4045 aluminum alloys were chosen for this study since these aluminum alloys are commonly used in clad products.
Two series of experiments were performed to investigate the effect of casting parameters on the solidification and cooling of the ingots such as casting speed, water flow rate, and the superheat of the molten aluminum. A set of seven thermocouples were embedded in the ingot during the cast to capture the thermal history of the ingot. Melt poisoning with a zinc rich alloy was also performed as an independent method of determining the sump depth and shape.
Experienced gained from the first series of experiments allowed improvements to be made to the experiment design for the second series of experiments. Thermocouples must be supported so they are not pushed out of position by the jet of molten aluminum entering the mould. Grounded thermocouples of at least 1.5 mm in diameter were recommended to survive the high temperatures of the molten aluminum. Knowledge gained from the experiments of the conventional DC caster allowed design and development of an experimental co-caster mould that will be useful for future research at NGTC.
Melt poisoning and thermocouples were complementary measurement methods that should be used together. In all three alloys, the liquidus sump profile generated by the thermocouple implants correlated well with the etched sumps of the melt poisoned ingots. Primary and secondary water flow rates beyond 1.79 L/s and increasing the superheat by 30°C did not have significant effect of the cooling rate with solidified ingots, but all casting experiments showed that the thermal histories and sump profiles were very sensitive to the casting speed. The sump depth increased with increasing casting speed in all casting experiments. The sump depth increased directly proportionally to the Péclet number and the sump depth could be predicted using a linear regression model by calculating the Péclet number. The formation of remelting bands were seen in the surface of the AA3003 and AA4045 ingots, but were not apparent in the AA6111 ingots. A fast Fourier transform performed on the data obtained from the thermocouples that were inserted in the mould wall showed that remelting occurred at regular intervals and that the frequency increased with casting speed. The thermocouples in the mould also indicated that AA6111 had a higher rate of heat transfer than AA3003 or AA4045. The AA6111 ingots had a higher rate of heat transfer in the mould than for the other alloys. This was evidence that there was a smaller air gap formation between the ingot and the mould in AA6111.
This research on the effects of casting parameters on DC cast ingots made using the three alloys, AA3003, AA6111, and AA4045, is beneficial in the development of a design of an experimental lab-scale co-caster for validation of a computational fluid dynamics (CFD) model of the Fusion™ Technology process.
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The place of DBS in Japan's movement toward the highly advanced information society /Mitani, Junko January 1989 (has links)
This thesis focuses on the development of the Direct Broadcasting Satellite in Japan under its Kodo Johoka Shakai (Highly Advanced Information Society) policy. The field of new media policies is relatively new but very important in communications studies. The development of new media technologies changes into existing media systems, and profoundly influences economies which are increasingly dependent upon information services. / Japan's case is particularly interesting. Relatively little is known about its DBS policy compared to other industrialized countries, even though Japan has already begun to operate DBS under its own version of the "information society", the Kodo Johoka Shakai (Highly Advanced Information Society). The formulation of DBS policy is related to many factors, including space development, research and development, broadcasting, international telecommunications regulations and economic competition both in international and domestic markets. In order to take these factors into consideration, an historical approach and institutional analysis are used in this thesis.
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Targeted persuasive advertisingWillmore, Christopher 11 1900 (has links)
The three essays of this thesis consider a firm’s choice of advertising campaign when advertising may be conditioned on the preferences of individual consumers. In essay one, I show that a monopolist will use such advertising to turn sub-marginal consumers, who are not quite willing to pay for the good, into marginal consumers who are indifferent to paying for the good or going without it. The second essay considers the use of targeted advertising in duopoly, when one of the firms does not have access to advertising. I find that advertising will target those consumers most likely to switch to the non-advertising firm. Each firm sets a price just high enough to capture the consumers on either side of the advertising 'barrier’. The third essay looks at targeted
advertising in the context of Canadian public health. When the goals of government and industry are aligned, advertising by the firm may be an alternative superior to government advertising in the form of a public health education campaign.
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Wind-hydrogen energy systems for remote area power supplyJanon, Akraphon, s2113730@student.rmit.edu.au January 2010 (has links)
Wind-hydrogen systems for remote area power supply are an early niche application of sustainable hydrogen energy. Optimal direct coupling between a wind turbine and an electrolyser stack is essential for maximum electrical energy transfer and hydrogen production. In addition, system costs need to be minimised if wind-hydrogen systems are to become competitive. This paper investigates achieving near maximum power transfer between a fixed pitched variable-speed wind turbine and a Proton Exchange Membrane (PEM) electrolyser without the need for intervening voltage converters and maximum power point tracking electronics. The approach investigated involves direct coupling of the wind turbine with suitably configured generator coils to an optimal series-parallel configuration of PEM electrolyser cells so that the I-V characteristics of both the wind turbine and electrolyser stack are closely matched for maximum power transfer. A procedure for finding these optimal con figurations and hence maximising hydrogen production from the system is described. For the case of an Air 403 400 W wind turbine located at a typical coastal site in south-eastern Australia and directly coupled to an optimally configured 400 W stack of PEM electrolysers, it is estimated that up to 95% of the maximum achievable energy can be transferred to the electrolyser over an annual period. The results of an extended experiment to test this theoretical prediction for an actual Air 403 wind turbine are reported. The implications of optimal coupling between a PEM electrolyser and an aerogenerator for the performance and overall economics of wind-energy hydrogen systems for RAPS applications are discussed.
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