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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

Primary power for the Philippines I. Effect of variable compression ratio on the performance of tractor engine using alcohol. II. A comparative study of alcohol, gasoline, and kerosene as fuels for tractor engines /

Teodoro, Anastasio Lalota, January 1900 (has links)
Thesis (Ph. D.)--Cornell University, 1928. / The first article is from the University of the Philippines Natural and applied science bulletin, v. 1, no. 3, July, 1931 and the second ("Experiment station contribution no. 742") from the Philippine agriculturist, v. 20.
32

Spontaneous hydrogen evolution in direct methanol fuel cells /

Ye, Qiang. January 2005 (has links)
Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references (leaves 137-145). Also available in electronic version.
33

Impact of PWR spent fuel variations on TRU-fueled VHTRS

Alajo, Ayodeji Babatunde 15 May 2009 (has links)
Several alternative strategies are being considered as spent nuclear fuel (SNF) management options. Transuranic nuclides (TRU) are responsible for the SNF long-term radiotoxicity beyond the first 500 years. One of the most viable approaches suggests creating new transmutation fuels containing TRUs for use in thermal and fast nuclear reactors. Irradiation of TRUs results in their transmutation and ultimate incineration by fission. The objective of this thesis is to analyze the impact of conventional PWR spent fuel variations on TRU-fueled Very High Temperature Reactor (VHTR) systems. This effort was focused on the prismatic core configuration. The 3D core models were created for use in calculations with the SCALE 5.1 code system. As part of the research effort, basic nuclear characteristics of TRUs were taken into consideration. The potential variations of PWR spent fuel compositions were modeled with the International Atomic Energy Agency (IAEA) Nuclear Fuel Cycle Simulation System, VISTA. The VHTR configurations with varying TRU compositions were analyzed assuming a single-batch core operation. Their performance was compared to the VHTR cases with low enriched uranium (LEU). The analysis shows that TRUs can be effectively utilized in the VHTR systems. The TRU-fueled VHTRs exhibit favorable performance characteristics.
34

Possibilities of Alternative Vehicle Fuels : a literature review

Zhang, Taoju January 2015 (has links)
Historically, gasoline and diesel have been used as vehicle fuels for a long time. But the decline of oil supply and unstable oil price drive people to find alternative energy for vehicle fuel. Alternative energy solutions may shift energy consumption to less carbon, less pollutions and provide more energy diversity. These issues are investigated in the present literature review.   The first part of the thesis introduces different kinds of alternative energy for vehicles, such as biofuel, natural gas, hydrogen, liquefied petrol gas, electricity and compressed air. The presentations includes their utilization, production, environment effect, running performance, fuel property, market share, running and investigate cost and production barriers. The second part of the thesis work compares the properties of the alternative fuels and discusses the advantages and drawbacks of different types of fuel energies.   Compared with traditional fuels, alternative fuels have superiority in environment impact, sustainability and energy efficiency. Some of them have been used in reality and show a potential as future fuels. The author found that natural gas and liquefied petrol gas have low running costs, better environment performance and acceptable running range, and thus are able to substitute conventional fuels in the short term. Biofuel has better sustainability than gasoline. It will probably become more sustainable and cost effective in the mid-term period. Electricity can also become a future fuel in mid-term period since it has excellent emission performance and low running costs. Hydrogen is expected to substitute conversional fuels in the long term due to high investment costs and current unsustainable production pathway of the latter. The compressed air turned out not suitable for substituting conventional fuels because of poor efficiency and running range performance.
35

CFD modelling of the flow through a 4 valve I.C engine with late intake valve closure

Bokhary, Ahmad Y. F. January 1998 (has links)
No description available.
36

Impact of PWR spent fuel variations on TRU-fueled VHTRS

Alajo, Ayodeji Babatunde 15 May 2009 (has links)
Several alternative strategies are being considered as spent nuclear fuel (SNF) management options. Transuranic nuclides (TRU) are responsible for the SNF long-term radiotoxicity beyond the first 500 years. One of the most viable approaches suggests creating new transmutation fuels containing TRUs for use in thermal and fast nuclear reactors. Irradiation of TRUs results in their transmutation and ultimate incineration by fission. The objective of this thesis is to analyze the impact of conventional PWR spent fuel variations on TRU-fueled Very High Temperature Reactor (VHTR) systems. This effort was focused on the prismatic core configuration. The 3D core models were created for use in calculations with the SCALE 5.1 code system. As part of the research effort, basic nuclear characteristics of TRUs were taken into consideration. The potential variations of PWR spent fuel compositions were modeled with the International Atomic Energy Agency (IAEA) Nuclear Fuel Cycle Simulation System, VISTA. The VHTR configurations with varying TRU compositions were analyzed assuming a single-batch core operation. Their performance was compared to the VHTR cases with low enriched uranium (LEU). The analysis shows that TRUs can be effectively utilized in the VHTR systems. The TRU-fueled VHTRs exhibit favorable performance characteristics.
37

Optimized fuel cell grade hydrogen from methanol /

Choi, Yongtaek, January 2003 (has links)
Thesis (Ph. D.)--Lehigh University, 2004. / Includes bibliographical references and vita.
38

Hedonic price model for light-duty vehicles : consumers' valuations of automotive fuel economy /

Fan, Qin. January 2009 (has links)
Thesis (M.S.) in Resource Economics and Policy--University of Maine, 2009. / Includes vita. Includes bibliographical references (leaves 105-115).
39

Dynamic modeling, control and optimization of PEM fuel cell system for automotive and power system applications

Na, Woon Ki. January 2008 (has links)
Thesis (Ph.D.) -- University of Texas at Arlington, 2008.
40

Measuring the distribution of equity in terms of energy, environmental, and economic costs in the fuel cycles of alternative fuel vehicles with hydrogen pathway scenarios

Meyer, Patrick E. January 2010 (has links)
Thesis (Ph.D.)--University of Delaware, 2010. / Principal faculty advisor: Young-Doo Wang, School of Urban Affairs & Public Policy. Includes bibliographical references.

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