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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.
211

The development of the direct methanol fuel cell

Hogarth, Martin P. January 1995 (has links)
No description available.
212

Silver Nanowire Transparent Electrodes: Fabrication, Characterization, and Device Integration

Hosseinzadeh khaligh, Hadi January 2013 (has links)
Silver nanowire transparent electrodes have recently received much attention as a replacement for indium tin oxide (ITO) for use in various electronic devices such as touch panels, organic solar cells, and displays. The fabrication of silver nanowire electrodes on glass substrates with a sheet resistance as low as 9 Ω/□ and 90% optical transparency at 550 nm is demonstrated. These resistance and transparency values match that of commercially available indium tin oxide and are superior to other alternatives such as carbon nanotube electrodes. The nanowire electrodes are low cost and easy to fabricate. Moreover, by depositing nanowire films on plastic substrates, mechanically flexible electrodes are obtained. The silver nanowire electrodes are integrated into several electronic devices: transparent heaters, organic solar cells, and switchable privacy glass. The concerns about the suitability of silver nanowire electrodes for use in commercial electronic devices are discussed. High surface roughness, one of the major concerns, is addressed by introducing a new method of embedding silver nanowires in a soft polymer. The instability of silver nanowire electrodes under current flow is also demonstrated for the first time. It is shown that silver nanowire electrodes fail under current flow after ass little as 2 days. This failure is caused by Joule heating which causes the nanowires to break up and thus create an electrical discontinuity in the nanowire film. Suggestions for improving the longevity of the electrodes are given.
213

Direct methanol fuel cell with extended reaction zone anode : PtRu and PtRuMo supported on fibrous carbon

Bauer, Alexander Günter 05 1900 (has links)
The direct methanol fuel cell (DMFC) is considered to be a promising power source for portable electronic applications and transportation. At present there are several challenges that need to be addressed before the widespread commercialization of the DMFC technology can be implemented. The methanol electro oxidation reaction is sluggish, mainly due to the strong adsorption of the reaction intermediate carbon monoxide on platinum. Further, methanol crosses over to the cathode, which decreases the fuel utilization and causes cathode catalyst poisoning. Another issue is the accumulation of the reaction product CO₂ (g) in the anode, which increases the Ohmic resistance and blocks reactant mass transfer pathways. A novel anode configuration is proposed to address the aforementioned challenges. An extended reaction zone (thickness = ∼100-300 µm) is designed to facilitate the oxidation of methanol on sites that are not close to the membrane-electrode interface. Thus, the fuel concentration near the membrane may decrease significantly, which may mitigate adverse effects caused by methanol cross-over. The structure of the fibrous electrode, with its high void space, is believed to aid the disengagement of CO₂ gas. In this thesis the first objective was to deposit dispersed nanoparticle PtRu(Mo) catalysts onto graphite felt substrates by surfactant mediated electrodeposition. Experiments, in which the surfactant concentration, current density, time and temperature were varied, were conducted with the objective of increasing the active surface area and thus improving the reactivity of the electrodes with respect to methanol electro-oxidation. The three-dimensional electrodes were characterized with respect to their deposit morphology, surface area, composition and catalytic activity. The second objective of this work was to utilize the catalyzed electrodes as anodes for direct methanol fuel cell operation. The fuel cell performance was studied as a function of methanol concentration, flow rate and temperature by using a single cell with a geometric area of 5 cm². Increased power densities were obtained with an in-house prepared 3D PtRu anode compared to a conventional PtRu catalyst coated membrane. Coating graphite felt substrates with catalytically active nanoparticles and the utilization of these materials, is a new approach to improve the performance of direct fuel cells.
214

Metal oxides as electrode materials for electrochemical capacitors

Lao, Zhuo Jin. January 2006 (has links)
Thesis (M.Eng)--University of Wollongong, 2006. / Typescript. Includes bibliographical references: leaf 96-106.
215

Ion selective polymeric membranes as chemically selective coulometric electrodes

Bhakthavatsalam, Vishnupriya, Bakker, Eric January 2006 (has links) (PDF)
Dissertation (Ph.D.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references.
216

Studies on a novel type of electrogenerated chemiluminescence and electroanalysis of biomolecules at fluorosurfactant-modified electrodes

Chen, Zuofeng. January 2009 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 195-212) Also available in print.
217

Electrospun carbon nanofibers for electrochemical capacitor electrodes

Wang, Tong. January 2007 (has links)
Thesis (Ph. D.)--Textile and Fiber Engineering, Georgia Institute of Technology, 2007. / Committee Chair: Satish Kumar; Committee Member: Anselm Griffin; Committee Member: John D. Muzzy; Committee Member: Ravi Bellamkonda; Committee Member: Rina Tannenbaum.
218

Processing of porous electrodes for solid oxide fuel cells using tape casting and unidirectional freeze-drying

Bettge, Martin. Gielisse, Peter J. January 2004 (has links)
Thesis (M.S.)--Florida State University, 2004. / Advisor: Dr. Peter J. Gielisse, Florida State University, College of Engineering, Dept. of Mechanical Engineering. Title and description from dissertation home page (viewed Sept. 23, 2004). Includes bibliographical references.
219

Design, synthesis, and evaluation of bicyclic peptides as ammonium ionophores

Nowak, Cheryl L. January 2003 (has links)
Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: solution 13C-NMR study; olid phase peptide synthesis; bicyclic peptides; ammonium ionophores; valinomycin; ion selective electrode. Includes bibliographical references (p. 63-65).
220

Amorphous multi-component metals as electrode materials /

Cowell, E. William. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 103-106). Also available on the World Wide Web.

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