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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.
231

High magnetic field studies of BEDT-TTF organic conductors

Honold, Markus Michael January 1999 (has links)
No description available.
232

A Study of the Factors Influencing Job Satisfaction Among Texas High School Band Directors

Qualls, Barbara Ann 12 1900 (has links)
The problem with which this study was concerned was that of measuring and examining the level of job satisfaction among Texas high school band directors. The specific methodology included a quantitative comparison through confirmatory factor analysis of the factor structures of the sample of 109 Texas high school band directors and the norming population of 1460 industrial workers. There were two purposes for conducting the study. First, the relationships between an assortment of demographic variables and measured job satisfaction were examined. The second purpose was to measure the degree of fit of the Frederick Herzberg Dual-Factor Theory to the factor structure of the sample. Correlation, t ratio, and one-way analysis of variance were used to compare the demographic variables with measured job satisfaction. Confirmatory factor analysis through LISREL was used to examine and compare factor structures. Job satisfaction was measured with the Minnesota Satisfaction Questionnaire which was developed and tested through the Work Adjustment Project, Industrial Relations Center at the University of Minnesota. The twenty-item short-form retained the general reliability and validity measures of the 100-item long form. The Demographic Data Sheet is a researcher-constructed document used to gather data for use in classifying respondents by educational background, school classification, and out-of-Texas teaching experience. Respondents were also asked to indicate chronological age and number of years creditable teaching experience. Only when classified by educational background and school classification were respondents found to have significant differences in satisfaction scores. Those band directors who hold degrees in fields other than music have significantly lower satisfaction scores than those who have only music degrees. Directors from larger UIL classification schools have higher measured levels of job satisfaction than do those in smaller Texas schools. While there are strong similarities between the factor structures of the sample group and the norming population, the sample contained three distinct factors. The third factor, not identified in the norming population structure, was defined by the constructs of Social Status, Social Service, Authority, Ability Utilization, and Achievement. It was concluded that the Herzberg Dual-Factor Theory does not completely explain vocational adjustment among Texas high school band directors.
233

Choral Problems in the Unaccompanied Music of Francis Poulenc

Barnard, Jack Richard, 1932 01 1900 (has links)
The purpose of this study, ve to analyze the stylistic characteristics in the unaccompanied music of one twentieth century composer, Francis Poulenc, in order to discover the choral problems which would confront choruses and conductors as they performed his music. It is hoped that this study will not only enable choral conductors to better understand, interpret, and appreciate the music of Poulenc, but also will serve as a guide toward the investigation of other twentieth century composers and their works.
234

Small signal control of multiterminal dc/ac power systems

Chan, Sherman Man January 1981 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1981. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Includes bibliographical references. / by Sherman Man Chan. / Ph.D.
235

A bus structure for multi-microprocessing.

Haagens, Randolph B January 1978 (has links)
Thesis. 1978. M.S.--Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: leaves 166-175. / M.S.
236

Triplet Superfluidity in Quasi-one-dimensional Conductors and Ultra-cold Fermi Gases

Zhang, Wei 13 September 2006 (has links)
This thesis presents theoretical investigations of triplet superfluidity (triplet superconductivity) in quasi-one-dimensional organic conductors and ultra-cold Fermi gases. Triplet superfluidity is different from its s-wave singlet counterpart since the order parameter is a complex vector and the interaction between fermions is in general anisotropic. Because of these distinctions, triplet superfluids have different physical properties in comparison to the s-wave case. The author discusses in this thesis the interplay between triplet superconductivity and spin density waves in quasi-one-dimensional organic conductors, and proposes a coexistence region of the two orders. Within the coexistence region, the interaction between the two order parameters acquires a vector structure, and induces an anomalous magnetic field effect. Furthermore, the author analyzes the matter-wave interference between two p-wave Fermi condensates, and proposes a polarization effect. For a single harmonically trapped p-wave Fermi condensate, the author also shows that the expansion upon release from the trap can be anisotropic, which reflects the anisotropy of the p-wave interaction.
237

Tension minimale de contournement des isolateurs givrés en région de fonte /

Barahmand, Sohrab, January 1985 (has links)
Mémoire (M. Sc.A.)-- Université du Québec à Chicoutimi, 1985. / Bibliogr.: f. [94]-99. Document électronique également accessible en format PDF. CaQCU
238

Modélisation en 3-D de l'accumulation de glace sur un cyclindre fixe par la méthode du cheminement aléatoire /

Lébatto, Élie Bérenger, January 2004 (has links)
Thèse (M.Eng.) -- Université du Québec à Chicoutimi, 2004. / Bibliogr.: f. [70]-76. Document électronique également accessible en format PDF. CaQCU
239

Enhancing a regular discipline of common prayer at Grace Episcopal Church in Orange Park, FL through the employment of shared musical leadership

Hart, James R. January 2002 (has links)
Thesis (D.W.S.)--Institute for Worship Studies, 2002. / Abstract. Includes bibliographical references (leaves 157-162).
240

Apatite based materials for solid oxide fuel cell (SOFC) and catalytic applications

Gasparyan, Hripsime 01 October 2012 (has links)
Low cost silicates with apatite-structure (general formula of apatite A10-xM6O26±δ, where A = rare earth or alkaline earth and M= Si, Ge, P, V..) have been proposed recently as promising solid electrolyte materials (oxygen ion conductors) for use at intermediate temperature solid oxide fuel cells (SOFCs). These materials exhibit sufficiently high ionic conductivity (e.g. ~ 0.01 S cm-1 at 700 oC), which is dominated by the interstitial site mechanism and can exceed that of yttria-stabilized-zirconia (YSZ), the solid electrolyte used in state-of-the-art SOFCs. The apatite structure is tolerant to extensive aliovalent doping, which has been applied for improving ionic conductivity. In this work are presented results concerning synthesis, conductivity and catalytic characterization of Fe- and/or Al-doped apatite type lanthanum silicates (ATLS) of the general formula La10-zSi6-x-yAlxFeyO26±δ as well as electrochemical characterization of interfaces of ATLS pellets with perovskite and Ni-based electrodes. The aim was to investigate the properties of these ATLS material, in particular as it concerns their potential use as SOFC components or as catalysts in oxidation reactions. The conductivity of pellets prepared from ATLS powders synthesized via four different methods and having different grain size was measured under air and at different temperatures in the range 600 -850 oC, aiming to identification of the effect of composition (doping), method of synthesis, grain size and pellet sintering conditions. For electrolytes of the same composition, those prepared via mechanochemical activation exhibited the highest conductivity, which was improved with increasing Al- and decreasing Fe-content. In state-of-the-art SOFCs perovskite electrodes are used as cathodes and Ni-based electrodes as anodes, thus electrochemical characterization of perovskite and Ni-based/ATLS interfaces was carried out. As it concerns perovskite/ATLS interfaces, the characterization focused on the study of the open circuit AC impedance characteristics of a La0.8Sr0.2Ni0.4Fe0.6O3-δ/La9.83Si5Al0.75Fe0.25O26±δ interface, at temperatures 600 to 800 oC and oxygen partial pressures ranging from 0.1 to 20 kPa. Under the aforementioned conditions, it was observed that the impedance characteristics of the interface were determined by at least two different processes, corresponding to two partially overlapping depressed arcs in the Nyquist plots. The polarization conductance of the interface was found to increase with increasing temperature as well as with increasing oxygen partial pressure, following a power law dependence. The electrochemical characterization of Ni-based electrodes/ATLS interfaces involved study of the electrochemical characteristics of NiO-apatite cermet electrodes as well as a Ni sputtered electrode interfaced with Al- or Fe-doped apatite electrolytes, under hydrogen atmospheres. The impedance characteristics of these electrodes were found to be determined by up to three different processes, their relative contribution depending on the electrode microstructure, Ni content (as it concerns the cermet electrodes), temperature, hydrogen partial pressure and applied overpotential. Aiming to investigation of potential catalytic properties of ATLS materials the catalytic activity for CO combustion of a series of ATLS powders was studied. For this purpose, two series of apatite-type lanthanum silicates La10-xSi6-y-zAlyFezO27-3x/2-(y+z)/2 (ATLS), undoped or doped with Al and/or Fe, were synthesized via sol-gel and modified dry sol-gel methods and tested as catalysts for CO combustion. The experiments revealed that the ATLS powders were catalytically active for CO combustion above approximately 300 oC, with light-off temperatures T50 (50% conversion of CO) ranging from 505 to 629 oC. The study focused on the effect on catalytic activity of the synthesis method and doping with Al and/or Fe. Non-doped ATLS with stoichiometric structure, namely La10Si6O27 prepared via the sol-gel method, exhibited the highest catalytic activity for CO oxidation among all tested compositions, the comparison being based on the measured catalytic rate (expressed per surface area of the catalyst) under practically differential conditions. Compared to La-Sr-Mn-O and La-Sr-Co-Fe-O perovskite powders, the tested ATLS powders exhibited lower catalytic activity for CO oxidation. / -

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