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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.
311

A CONDUCTOR’S GUIDE TO DAVID DEL TREDICI’S IN WARTIME

Moore, Joe David 01 January 2013 (has links)
Pulitzer Prize-winning composer David Del Tredici (b. 1937) has gained recognition as a composer for both instrumental and vocal settings. Although his instrumental contributions include solo, chamber, and orchestral works, to date he has only written one composition for wind band. A conductor must devote himself / herself to score study and analysis in order to form an accurate interpretation and to conduct effective rehearsals. A vital part of score study and analysis is familiarity with the composer’s technique and style of writing. A brief biographical sketch presents Del Tredici’s background, education, honors and awards, academic career, and influences, as well as a discussion of his compositional and orchestration techniques. Both movements of In Wartime are analyzed using the elements of melody, harmony, form, rhythm (which includes tempo, meter, rhythm, and rhythmic techniques), orchestration, texture, and dynamics. Rehearsal considerations for each movement are presented based on the author’s experience rehearsing and conducting In Wartime. The intention of this document is to facilitate conductors in their study and preparation of In Wartime in order that they may realize more effective rehearsals and inspired performances. Included in the appendices are trumpet parts transposed to the key of B-flat and instructions for the construction of the wind machine indicated in the score.
312

Conducting metallopolymers with tridentate ligands and coordination chemistry with corresponding model compounds

Keskin, Şeyma 22 July 2014 (has links)
Conducting polymers that contain metals are remarkable materials, because they have the properties of both organic backbones and metals. Depending on the position of the metal relative to the conjugated backbone, i.e. attached to or directly in the backbone, these two can couple resulting in advancement of the functionality and therefore potential applications of these types of materials. Complexes of tridentate ligands with donor atoms such as phosphorus, nitrogen, and sulfur also have a wide variety of applications. In addition, complexes of tridentate ligands have advantages of stability and control of electron density by variation of donor atoms. Therefore, conjugated polymers with tridentate ligand units will have promise for various applications and advantages in their designs. Complexes of PNP ligand with molybdenum and carbonyl ancillary ligands were synthesized and characterized. Isomerization and conversion reactions between them were investigated as well as the coordination modes. Many types of PNP ligands have been studied in the literature because the hemilabile property of the nitrogen atom promotes some catalytic reactions and gives different coordination geometries. Conducting polymers can be used as redox-active ligands and they can be used to control electron density on the metal attached to them. Synthesis and characterization of a novel polymerizable ligand 3,5-bis-EDOT-N,N-bis[2-diphenylphosphinoethyl]aniline was achieved. Related molybdenum complexes with ancillary ligands as carbonyls were also synthesized and characterized. Monomer complexes and the free ligand were electropolymerized and studied. Tris(bipyridine)ruthenium(II) chloride and analogous complexes have been studied extensively in the literature due to their luminescent and photochemical properties, and excited state lifetimes. Conducting polymers with similar ruthenium groups have been investigated for various applications. Synthesis of four ruthenium complexes with the polymerizable ligand 2,6-Bis[4-[2-(3,4-diethylenedioxy)thiophene]pyrazol-1-yl]pyridine and four different bidentate ligands were reproduced; electropolymerizations of the complexes were achieved; electrochemical, UV-Vis and luminescence studies were performed and discussed. Various complexes of copper, silver, platinum, and palladium with nitrogen and phosphorus donors have been reported for their luminescence behavior as well as their interesting structures. Model complexes of these metals with N,N-bis[2-(diphenylphosphino)ethyl]phenyl-amine (a PNP ligand) have been synthesized and characterized. Absorption and luminescence behaviors as well as the coordination modes were investigated. / text
313

Conducting polymer hydrogels for high-performance electrochemical devices

Liu, Borui 09 October 2014 (has links)
Conducting polymer hydrogels (CPHs) is a class of unique materials that synergize the advantages of conducting polymers (CPs) and polymer hydrogels together. It has been employed in many high-performance electrochemical devices for years, such as energy storage and biosensors. However, large limitations of applying CPHs into the abovementioned areas have been facing the researcher for a long time, mainly due to the difficulties from complicated materials synthesis and untenable nanostructures for potential applications. The drawbacks of previously reported CPHs have put numerous disadvantages onto their applications, partially because they have, for example, high prices, untunable microscale or nanoscale architectures, environmentally hazardous properties, and unscalable and time-consuming synthesis processes. In this thesis, we proposed a novel route for carrying out CPHs by one-step organics synthesis at ambient conditions. The CPHs have hierarchically porous nanostructures crosslinked in a three-dimensional (3D) way, which enable its stable mechanical, unique chemical and physical properties, and outstanding electrochemical properties for potential applicability in long-term energy storage devices and highly sensitive biosensors. With highly controllable nanostructures of the CPHs, our novel concept and material system could possibly be utilized in a broad range of electrochemical applications, including but not limited to lithium-ion batteries (LIBs) electrodes, electrochemical capacitors (ECs), biofuel cells, medical electrodes, printable electronic devices, and biosensors. / text
314

A Conductor's Introduction to the Performance of Modern Japanese Choral Music

Howell, Matthew Clayton January 2008 (has links)
Currently in Japan there are 5,202 choirs registered as part of the Japan Choral Association. The majority of these choirs are amateur or professional choirs. This situation contrasts with that in the United States where colleges and universities are the primary entities perpetuating the advancement of the choral art. Most likely because of this, there is little if any academic investigation of modern Japanese choral music. Even in Japan, there is not a substantial body of academic study of this literature. As a result, this repertoire is seldom, if ever, performed outside of Japan.Numerous problems confront Western choral conductors interested in programming modern Japanese choral music that is based on traditional Japanese musical idioms. In this document, I have provided information that will allow Japanese choral literature to be accessible to non-Japanese speaking conductors. This information is divided into four areas. First, an overview of Japanese music history is provided. Next, a discussion of the elements of traditional Japanese music such as genre types, modes and tonalities provides the necessary background for a conductor to approach modern Japanese choral music. Third, a practical method whereby non-Japanese speaking choral conductors may transcribe the two phonetic Japanese alphabets into readable English phonetics is proposed. Fourth, a practical approach to the performance of modern Japanese choral music, inclusive of various musical genres, voicing, and instrumental complements is suggested. Discussion of representative choral works by three native composers including a work based on a folk tune, a work for women's chorus, a work for men's chorus, and a composition for mixed chorus and traditional Japanese instrumental complement provides concrete application of the aforementioned discussions.Lastly, in this document I will provide information on several contemporary native Japanese composers, their compositions, and their publishing companies to facilitate the acquisition and performance of this rich choral repertory.
315

The Nightingale's Flight from Opera to Symphonic Poem: A Comparative Study of The Nightingale and The Song of the Nightingale by Igor Stravinsky

Couturiaux, Clay 12 1900 (has links)
An analysis of the transformation from Stravinsky's opera The Nightingale to The Song of the Nightingale, a symphonic poem by the same composer. The text includes a brief history of Stravinsky's life and the genesis of The Nightingale and The Song of the Nightingale. The bulk of the dissertation discusses actual changes employed by Stravinsky (with score examples). Patterns of modifications are identified and discussed as they relate to the composer's change of attitude in orchestration. The analysis focuses on overall patterns of alteration imposed by Stravinsky and their perceived effectiveness achieving a symphonic aural outcome.
316

A CONDUCTOR’S ANALYSIS OF VELJO TORMIS’ <em>LOODUSPILDID</em>

Frizzell, John David 01 January 2017 (has links)
Estonian composer Veljo Tormis (1930-2017) is one of the most prolific in his country’s history. A significant portion of his writing has been for choirs. Tormis composed most of his works under Soviet rule. During this communist reign of Estonia, Tormis turned to using traditional music. The source material for a large portion of Tormis’ choral output is regilaul, a type of ancient Estonian folk song. In 1991, Estonia gained their independence, thereby allowing Tormis’ compositions to be more easily seen, heard, and performed around the world. This dissertation presents a conductor’s analysis of a set of choral cycles composed by Tormis between 1964 and 1969, Looduspildid, or Nature Pictures. A set of cycles representing all of the seasons and incorporating prominent Estonian poetry, Loodispuldid represents one of Tormis’ most important works. It illustrates Tormis’ maturing style as he utilized a variety of 20th Century techniques like extended tertian harmonies, modal scales, pandiatonicism, clusters, and mixed meters. Tormis also employs his own orchestrally-derived techniques of carefully constructed simultaneous articulations along with cumulative chording. Each cycle contains its own unique style and feel. Sügismaastikud is perhaps the most tonal of the four. Most movements are pandiatonic and one uses the whole tone scale. On a macro level, Sügismaastikud moves from soft in the earlier movements to a fff climax on the final chord of the last movement. Talvemustrid also begins at a very soft dynamic level on a unison D4, grows to multiple ff dynamics throughout, and ends back at a soft dynamic on Db. The cycle is more harmonically adventurous than Sügismaastikud, with consistent chromaticism, octatonic scale, and marked dissonance. Suvenmotiivid only contains three movements, but continues the harmonic and rhythmic complexity of Sügismaastikud. The first movement, Põualim, immediately begins on a tritone with octatonic scale. Different meters occur simultaneously during the second movement, which also moves quickly through 4 keys. The final movement ends with orchestral voicing and a 10-note chord cluster. Kevadkillud contains six very short movements, most of which are pandiatonic like Sügismaastikud. There is far less chromaticism and harmonic complexity than the middle two cycles, almost as if Tormis is bringing the set full circle. Moreover, the final movement of this cycle (and the entire set) is really just one major chord with embellishments. As a set, Loodispuldid represents a thorough perspective of Tormis’ mature style. The analyses done as a part of this paper reveal an incredible efficiency in his writing. Motives have purpose and context. Each movement possesses a well-defined harmonic language and rhythmic identity. A variety of formal structures exist, from binary to rondo. Even the many through-composed movements are expertly crafted with clear direction.
317

Magnetic Resonance Imaging (MRI) and electromechanical study of electro-active polymers for application in soft actuators

Naji, Leila January 2007 (has links)
It is more than a decade that Ionic Polymer-Metal Composites (IPMCs) have been known as an exciting class of smart materials and attracted growing worldwide attention. IPMCs are soft and flexible, and can generate large and reversible strains in response to electrical stimulus. Thus, they have potential applications in industrial and biomedical fields, as actuators. Before these applications can be realized , however, the performance of IPMCs must be understood and improved through improvement of component characteristics and of preparation methods. In general, the aim of this thesis is to gain a fundamental understanding of the chemical and structural factors that affect the electromechanical performance of IPMCs. To this end, a multi-technique investigation is applied to correlate the electrochemical and electromechanical behavior of IPMCs, during operation, with their chemistry, microstructure and nanostructure. Researchers have suggested several plausible mechanical and mathematical models to reveal that ion transport occurs within IPMCs and that it is an important factor in their actuation performance. However, there is still a need for further experimental studies to help refine our understanding of the actuation mechanism of these materials. In this work, the powerful, non-invasive and non-destructive technique of Magnetic Resonance Imaging (MRI) is employed to study the internal structure and water content distribution in Nafion membranes and also IPMCs. Moreover, MRI is also applied to image electrically-induced diffusion of ions with their associated water molecules in real time, in operating IPMC actuators. This forms the major part of this project and, to the best of our knowledge, it is the first recorded electrochemical experiment of this kind. The size and dimensions of IPMCs can affect their actuation performance. Thus, in this work, model IPMC actuators are prepared based on the available commercial Nafion membrane and fabricated cast Nafion membrane and their electromechanical behaviors are compared. The effect of parameters such as electrode composition and Nafion thickness on actuation behavior is also studied by measuring displacement and force generation of the IPMC actuators during actuation cycles. Simultaneous current and electrochemical measurements are made to correlate electrochemical processes with actuation behavior directly. Scanning electron microscopy (SEM) is also used to study the internal and surface structure of IPMCs.
318

Single molecule studies of seven transmembrane domain proteins

Berthoumieu, Olivia January 2011 (has links)
This work aimed at studying biophysical properties of two membrane proteins, one of potential nanotechnological use, bacteriorhodopsin, and one potential drug target, the NTS1 neurotensin receptor, at the single molecule scale. Bacteriorhodopsin (BR) is the only protein in the purple membrane (PM) of the halophilic organism Halobacterium salinarium. It is a light-driven proton pump converting light into a transmembrane proton gradient through isomerization of its retinal chromophore. Its stability, as well as its photoactivity remaining in dry protein layers, has made BR an attractive material for biomolecular devices. Numerous studies have been published on this topic; however, they have all used BR within the PM, on relatively large (µm-wide) surfaces. Here, conducting-probe atomic force microscopy (C-AFM) analysis was performed after removing most of the membrane lipids. For the first time, it was shown that the molecular conductance of BR can be reversibly photoswitched with predictable wavelength sensitivity. Intimate and robust coupling to gold electrodes was achieved by using a strategically engineered cysteine which, combined with partial delipidation, generated protein trimers homogenously orientated on the surface. Numerous controls using biophysical (SPR, ellipsometry, Kelvin-probe AFM) and chemical (photocurrent, cyclic voltammetry) techniques confirmed the wavelength specificity of the photoswitch, the anchoring role of the mutation and the homogenous orientation of the protein on the gold surface. Neurotensin is a brain and gastrointestinal 13 amino acid peptide acting as a neuromodulator in the central nervous system and as a hormone in the periphery. Its wide range of biological activities is primarily mediated through its binding to the neurotensin type 1 receptor (NTS1). NTS1 expressed in E.coli was purified and inserted into 100 nm brain polar lipid liposomes in a conformation which retained its ligand-binding capabilities. Initial AFM characterisation was performed as a prelude for ligand-receptor interaction studies, including high resolution imaging, force spectroscopy and solid state NMR approaches.
319

Olympic Dances by John Harbison, a Lecture Recital together with Three Recitals of Selected Works of D. Holsinger, P. Granger, K. Husa, B. Rands, R. Vaughan Williams, and Others

Kohlenberg, Kenneth Howard 12 1900 (has links)
John Harbison's Olympic Dances was composed in 1996 and premiered in February 1997. The work was written as a piano score before it was orchestrated for a wind ensemble of 25 winds and two percussionists.The first section of the paper focuses on the various influences that have affected Harbison's compositional style. The composer's educational background includes several prominent teachers whose instruction had great impressions. Special emphasis is placed on those characteristics of Harbison's style that are most prominent in the work with which this paper is concerned, Olympic Dances. Olympic Dances was commissioned by the College Band Directors National Association and premiered at the CBDNA Twenty-ninth National Conference in Athens, Georgia, in a collaborative performance of the University of North Texas Wind Symphony and Pilobolus Dance Theatre. The second part of the paper presents an historical overview of CBDNA commissioning projects along with a summary of the genesis of the commissioning of Olympic Dances. The primary focus of the study appears in the third section of the paper. An analysis of the four movements of Olympic Dances is presented with attention to the objective elements of harmonic and melodic structures along with a focus on orchestration and scoring. This section considers the composer's thoughts on aesthetic concerns, suggested through his written program notes, and elucidated by way of an interview with the author. Special performance concerns related to rehearsal and conducting conclude this chapter. The paper also includes a transcription of the author's interview with John Harbison, a bibliography and a select discography of recent recordings of his works that are currently available.
320

Suspended Polypyrrole Films Supporting Alamethicin Reconstituted Bilayer Membranes

Northcutt, Robert 03 August 2012 (has links)
This thesis presents a novel architecture for a sensing element fabricated from a conducting polymer and a bioderived membrane. The thin film device provides controlled, selective ion transport from a chemical concentration and produces measurable electrical signals, ion storage, and small scale actuation. A chemical gradient applied across a bioderived membrane generates ion flow through protein transporters in the presence of a gating signal. A conducting polymer undergoes ion ingress/egress in the presence of an electrical and chemical potential, which causes a change on the polymers conformal backbone. A ligand (or) voltage gated protein in the bioderived membrane results in ion transport through the bioderived membrane. Integrating the two electroactive materials provides a unique architecture which takes advantage of their similarities in ionic function to produce a device with controlled and selective ion transport. The chemoelectromechanical device is one that couples chemical, electrical, and mechanical potentials through number of ions, dielectric displacement, and strain. The prototype consists of a stacked thin conducting polymer film and bioderived membrane which form three aqueous chambers of varying ionic concentrations. The top chamber contains an electrolytic solution, and the bottom chamber contains deionized water adjacent to the conducting polymer. The current that passes through a conducting polymer for an applied electrical signal is based on the level of doping/undoping and therefore can be used as a method of sensing protein function in the sensing element. This architecture results in a sensing element applicable in real time chemical sensors, volatile organic compound detectors, and bioanalytical sensors. The conducting polymer layer is formed from polypyrrole (PPy) doped with sodium dodecylbenzenesulfonate (NaDBS), and the bilayer lipid membrane is formed from 1,2-diphytanoyl-sn-glycero-3-phosphocholine (DPhPC) reconstituted with the protein alamethicin. The magnitude of current required to span a 175 µm pore was empirically found to be 326.5 A/cm2 and is based on electrode condition, electrode surface area, pyrrole concentration, and electrical potential. A micron-scale pore through a silicon substrate is spanned by a thin PPy(DBS) layer, forming a bridge which supports the bioderived membrane. The bioderived membrane is reconstituted with alamethicin, a voltage-gated protein extracted from trichoderma viride. Ion transport experiments were performed to characterize the PPy(DBS) layer and the bioderived membrane and are represented as electrical equivalents for subsequent analysis. The equivalent impedance of polypyrrole was calculated to be 1.7847±0.1735Ωcm2 and capacitance was calculated to be 1.2673±0.1823µF/cm2. The equivalent impedance of a bioderived membrane was calculated to be 1.654±1.9894MΩcm2, capacitance was calculated to be 1.1221± 0.239µF/cm2, and alamethicin resistance was calculated to be 1.025± 0.7228MΩcm2. Thus, using impedance measurements in the conducting polymer layer, it is proposed that a scaled up sensing element can be fabricated using the suspended polypyrrole supported bioderived membrane.

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