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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.
121

Christopher Rouse's Wolf Rounds: Compositional Insight and World Premiere Performance Preparation

Rand, Catherine A. 27 June 2007 (has links)
The purpose of this essay is to explore the commissioning process of a wind ensemble piece by notable composer Christopher Rouse, and its significance to the wind ensemble repertoire. This essay will use the University of Miami Frost Wind Ensemble and Christopher Rouse's Wolf Rounds as the primary example. This discussion will provide an extensive background review of Christopher Rouse's early musical experience and life's accomplishments. It will focus on his creative process and document the performance preparation of Wolf Rounds as experienced by the Frost Wind Ensemble, conducted by Professor Gary D. Green. The final part of this essay will investigate the compositional insight of Wolf Rounds as well as the inspiration and motivation of Rouse to write for the wind ensemble genre. While Rouse has written for many different types of ensembles, this will be his first published addition to the wind repertoire. Wolf Rounds was chosen as the primary composition because of its significance to the composer as his first composition for winds and percussion.
122

Dual-ion Conducting Nanocompoiste for Low Temperature Solid Oxide Fuel Cell

Wang, Xiaodi January 2012 (has links)
Solid oxide fuel cells (SOFCs) are considered as one of the most promising power generation technologies due to their high energy conversion efficiency, fuel flexibility and reduced pollution. There is a broad interest in reducing the operating temperature of SOFCs. The key issue to develop low-temperature (300~600 °C) SOFCs (LTSOFCs) is to explore new electrolyte materials. Recently, ceria-based composite electrolytes have been developed as capable alternative electrolyte for LTSOFCs. The ceria-based composite electrolyte has displayed high ionic conductivity and excellent fuel cell performance below 600 °C, which has opened up a new horizon in the LTSOFCs field. In this thesis, we are aiming at exploring nanostructured composite materials for LTSOFCs with superior properties, investigating the detailed conduction mechanism for their enhanced ionic conductivity, and extending more suitable composite system and nanostructure materials.In the first part, core-shell samarium doped ceria-carbonate nanocomposite (SDC/Na2CO3) was synthesized for the first time. The core-shell nanocomposite was composed of SDC particles smaller than 100 nm coated with amorphous Na2CO3 shell. The nanocomposite has been applied in LTSOFCs with excellent performance. A freeze dry method was used to prepare the SDC/Na2CO3 nanocomposites, aiming to further enhance its phase homogeneity. The ionic conduction behavior of the SDC/Na2CO3 nanocomposite has been studied. The results indicated that H+ conductivity in the nanocomposite is predominant over O2- conductivity with 1-2 orders of magnitude in the temperature range of 200-600 °C, indicating the proton conduction in the nanocomposite mainly accounts for the enhanced total ionic conductivity. The influence of Na2CO3 content to the proton and oxygen ion conductivity in the nanocomposite was studied as well.In the second part, both the proton and oxygen ion conduction mechanisms have been studied. It is suggested that the interface in the nanocomposite electrolyte supplies high conductive path for the proton, while oxygen ions are probably transported by the SDC grain interiors. An empirical “Swing Model” has been proposed as a possible mechanism of superior proton conduction, while oxygen ion conduction is attributed to oxygen vacancies through SDC grain in nanocomposite electrolyte.In the final part, a novel concept of non-ceria-salt-composites electrolyte, LiAlO2-carbonate composite electrolyte, has been investigated for LTSOFCs. The LiAlO2-carbonate electrolyte exhibits good conductivity and excellent fuel cell performances below 650 °C. The work not only developed a more stable composite material, but also strongly demonstrated that the high ionic conductivity is mainly related to interface effect between oxide and carbonate. As a potential candidate for nanocomposite, uniform quasi-octahedral CeO2 mesocrystals was synthesized in this thesis work as well. The CeO2 mesocrystals shows excellent thermal stability, and display potential for fuel cell applications. / <p>QC 20120529</p>
123

Review of educational objectives for conducting classes for the undergraduate through the doctoral degree

Zirkman, Richard A. 03 June 2011 (has links)
The purpose of the study was to review educational objectives for conducting classes for the undergraduate through the doctoral degree. This included one hundred and seventy-three behavioral objectives and three basic methods of evaluation.Specific conducting textbooks were reviewed as were the conclusions from related research. Articles relating to the preparation of the conductor and conducting curricula were also reviewed. The survey instrument designed for this dissertation was mailed to teachers of conducting at the eighteen selected schools where programs were commensurate with this study.FindingsConducting textbooks are used most frequently at the undergraduate level.Equipment most frequently used for evaluation are the tape recorder and videotape (VTR).Compositions of Bach are most frequently used in conducting classes followed by Mozart, Beethoven, Haydn and Handel. Music of Schubert, Tschaikovsky, Brahms, Holst, and Stravinsky are also used frequently.Most teachers provide practical conducting experiences daily or weekly but opportunities to conduct live ensembles are still relatively scarce for undergraduates.All teachers teach conducting techniques and score analysis and memory. Seventy-six percent of the respondents also teach rehearsal techniques.Visual observation of conducting students is the most frequently used method of evaluation.Teachers feel there should be more classes, more class meetings, and a greater variety of conducting classes required--especially at the undergraduate level.ConclusionsEducational objectives should be clearly stated for conducting courses at all levels.Evaluation of conducting students should be provided in a variety of forms that are clear and meaningful to the student and be based on stated educational objectives.Conducting courses should be developed for opera, ballet, theater, oratorios, and jazz ensembles.The number of conducting courses, class meetings, and credit should be increased.More conducting classes should be required for the music education major and conducting major, especially at the undergraduate level.Ensembles should be frequently and consistently available to conducting students.
124

Tip-based Creation and Functionalization of Nanoscale Surface Patterns

Woodson, Michael E 29 July 2008 (has links)
<p>Nanostructures are being intensely studied due to unusual material properties and simple scaling concerns in the microelectronics industry. Fabricating useful nano-scale structures and devices, either by arranging existing nanoparticles such as carbon nanotubes or by manipulating bulk materials into nanometer-scale geometries, is a challenging prospect. One promising approach is to generate a nanometer-scale pattern and transfer that geometry into another material. The research described in this dissertation concerns the fabrication of nanometer-scale patterns, by Atomic Force Microscope-based methods and Electron Beam Lithography, on planar surfaces and the transfer of those patterns into functional materials. Differences in surface energy were used to guide the growth of bulk conducting polymer along predefined nano-scale patterns. Carbon nanotubes were assembled into an ordered and continuous material with no guidance and used to lithographically write silicon oxide nanopatterns on a silicon surface. Finally, the two previous projects were combined, and surface energy patterns were used to guide the deposition of dense carbon nanotube bundles along a planar substrate.</p> / Dissertation
125

Computational study of the transport mechanisms of molecules and ions in solid materials

Zhang, Yingchun 02 June 2009 (has links)
Transport of ions and molecules in solids is a very important process in many technological applications, for example, in drug delivery, separation processes, and in power sources such as ion diffusion in electrodes or in solid electrolytes. Progress in the understanding of the ionic and molecular transport mechanisms in solids can be used to substantially increase the performance of devices. In this dissertation we use ab initio calculations and molecular dynamics simulations to investigate the mechamisn of transport in solid. We first analyze molecular transport and storage of H2. Different lightweight carbon materials have been of great interest for H2 storage. However, pure carbon materials have low H2 storage capacity at ambient conditions and cannot satisfy current required storage capacities. Modification of carbon materials that enhance the interaction between H2 and absorbents and thus improve the physisorption of H2, is needed for hydrogen storage. In this dissertation, corannulene and alkali metal-doped corannulene are investigated as candidate materials for hydrogen storage. Molecularalso investigated. Using computational chemistry, we predict enhanced H2 adsorption on molecular systems with modification and hydrogen uptake can reach DOE target of 6.5wt% at at 294 bar at 273 K, and 309 bar at 300 K. In the second part of this dissertation, we study the lithium ion transport from a solid electrolyte phase to a solid electrode phase. Improvement of ionic transport in solid electrolytes is a key element in the development of the solid lithium ion batteries. One promising material is dilithium phthalocyanine (Li2Pc), which upon self-assembly may form conducting channels for fast ion transport. Computational chemistry is employed to investigate such phenomena: (1) to analyze the crystalline structure of Li2Pc and formation of conducting channels; (2) to understand the transport of Li ions inside channels driven by an electric field; (3) to study the continuity of the conducting channels through interface. The study shows Li2Pc has higher conductivity than PEO as electrolyte.
126

µL

Su, Min-Chen 26 July 2000 (has links)
none
127

Emulsion polymerization of aniline with ionic organic sulfonic acid surfactant

Hsu, Pei-Pin 10 June 2003 (has links)
µL
128

Enhanced rates of electron transport in conjugated-redox polymer hybrids /

Cameron, Colin, January 2000 (has links)
Thesis (Ph.D.), Memorial University of Newfoundland, 2000. / Bibliography: leaves 178-185.
129

Configuration interaction (singles) study of geometric and electronic properties of conducting polymers /

Chakraborty, Debanond, January 2000 (has links)
Thesis (M.Sc.), Memorial University of Newfoundland, 2000. / Bibliography: leaves 162-182.
130

Characterization of thiophene-based conducting polymers by pyrolysis-gas chromatography-mass spectrometry /

Tang, Shu, January 1999 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland, 2000. / Bibliography: p. 115-121.

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