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- Genre: Doctoral Dissertation
Description
Nitrate is the most prevalent water pollutant limiting the use of groundwater as a potable water source. The overarching goal of this dissertation was to leverage advances in nanotechnology to improve nitrate photocatalysis and transition treatment to the full-scale. The research objectives were to (1) examine commercial and synthesized photocatalysts, (2) determine the effect of water quality parameters (e.g., pH), (3) conduct responsible engineering by ensuring detection methods were in place for novel materials, and (4) develop a conceptual framework for designing nitrate-specific photocatalysts. The key issues for implementing photocatalysis for nitrate drinking water treatment were efficient nitrate removal at neutral pH and by-product selectivity toward nitrogen gases, rather than by-products that pose a human health concern (e.g., nitrite). Photocatalytic nitrate reduction was found to follow a series of proton-coupled electron transfers. The nitrate reduction rate was limited by the electron-hole recombination rate, and the addition of an electron donor (e.g., formate) was necessary to reduce the recombination rate and achieve efficient nitrate removal. Nano-sized photocatalysts with high surface areas mitigated the negative effects of competing aqueous anions. The key water quality parameter impacting by-product selectivity was pH. For pH < 4, the by-product selectivity was mostly N-gas with some NH4+, but this shifted to NO2- above pH = 4, which suggests the need for proton localization to move beyond NO2-. Co-catalysts that form a Schottky barrier, allowing for localization of electrons, were best for nitrate reduction. Silver was optimal in heterogeneous systems because of its ability to improve nitrate reduction activity and N-gas by-product selectivity, and graphene was optimal in two-electrode systems because of its ability to shuttle electrons to the working electrode. "Environmentally responsible use of nanomaterials" is to ensure that detection methods are in place for the nanomaterials tested. While methods exist for the metals and metal oxides examined, there are currently none for carbon nanotubes (CNTs) and graphene. Acknowledging that risk assessment encompasses dose-response and exposure, new analytical methods were developed for extracting and detecting CNTs and graphene in complex organic environmental (e.g., urban air) and biological matrices (e.g. rat lungs).
ContributorsDoudrick, Kyle (Author) / Westerhoff, Paul (Thesis advisor) / Halden, Rolf (Committee member) / Hristovski, Kiril (Committee member) / Arizona State University (Publisher)
Created2013
Description
Contaminants of emerging concern (CECs) present in wastewater effluent can threat its safe discharge or reuse. Additional barriers of protection can be provided using advanced or natural treatment processes. This dissertation evaluated ozonation and constructed wetlands to remove CECs from wastewater effluent. Organic CECs can be removed by hydroxyl radical formed during ozonation, however estimating the ozone demand of wastewater effluent is complicated due to the presence of reduced inorganic species. A method was developed to estimate ozone consumption only by dissolved organic compounds and predict trace organic oxidation across multiple wastewater sources. Organic and engineered nanomaterial (ENM) CEC removal in constructed wetlands was investigated using batch experiments and continuous-flow microcosms containing decaying wetland plants. CEC removal varied depending on their physico-chemical properties, hydraulic residence time (HRT) and relative quantities of plant materials in the microcosms. At comparable HRTs, ENM removal improved with higher quantity of plant materials due to enhanced sorption which was verified in batch-scale studies with plant materials. A fate-predictive model was developed to evaluate the role of design loading rates on organic CEC removal. Areal removal rates increased with hydraulic loading rates (HLRs) and carbon loading rates (CLRs) unless photolysis was the dominant removal mechanism (e.g. atrazine). To optimize CEC removal, wetlands with different CLRs can be used in combination without lowering the net HLR. Organic CEC removal in denitrifying conditions of constructed wetlands was investigated and selected CECs (e.g. estradiol) were found to biotransform while denitrification occurred. Although level of denitrification was affected by HRT, similar impact on estradiol was not observed due to a dominant effect from plant biomass quantity. Overall, both modeling and experimental findings suggest considering CLR as an equally important factor with HRT or HLR to design constructed wetlands for CEC removal. This dissertation provided directions to select design parameters for ozonation (ozone dose) and constructed wetlands (design loading rates) to meet organic CEC removal goals. Future research is needed to understand fate of ENMs during ozonation and quantify the contributions from different transformation mechanisms occurring in the wetlands to incorporate in a model and evaluate the effect of wetland design.
ContributorsSharif, Fariya (Author) / Westerhoff, Paul (Thesis advisor) / Halden, Rolf (Committee member) / Fox, Peter (Committee member) / Herckes, Pierre (Committee member) / Arizona State University (Publisher)
Created2013
Description
The influence of climate variability and reclaimed wastewater on the water supply necessitates improved understanding of the treatability of trace and bulk organic matter. Dissolved organic matter (DOM) mobilized during extreme weather events and in treated wastewater includes natural organic matter (NOM), contaminants of emerging concern (CECs), and microbial extracellular polymeric substances (EPS). The goal of my dissertation was to quantify the impacts of extreme weather events on DOM in surface water and downstream treatment processes, and to improve membrane filtration efficiency and CECs oxidation efficiency during water reclamation with ozone. Surface water quality, air quality and hydrologic flow rate data were used to quantify changes in DOM and turbidity following dust storms, flooding, or runoff from wildfire burn areas in central Arizona. The subsequent impacts to treatment processes and public perception of water quality were also discussed. Findings showed a correlation between dust storm events and change in surface water turbidity (R2=0.6), attenuation of increased DOM through reservoir systems, a 30-40% increase in organic carbon and a 120-600% increase in turbidity following severe flooding, and differing impacts of upland and lowland wildfires. The use of ozone to reduce membrane fouling caused by vesicles (a subcomponent of EPS) and oxidize CECs through increased hydroxyl radical (HO●) production was investigated. An "ozone dose threshold" was observed above which addition of hydrogen peroxide increased HO● production; indicating the presence of ambient promoters in wastewater. Ozonation of CECs in secondary effluent over titanium dioxide or activated carbon did not increase radial production. Vesicles fouled ultrafiltration membranes faster (20 times greater flux decline) than polysaccharides, fatty acids, or NOM. Based upon the estimated carbon distribution of secondary effluent, vesicles could be responsible for 20-60% of fouling during ultrafiltration and may play a vital role in other environmental processes as well. Ozone reduced vesicle-caused membrane fouling that, in conjunction with the presence of ambient promoters, helps to explain why low ozone dosages improve membrane flux during full-scale water reclamation.
ContributorsBarry, Michelle (Author) / Barry, Michelle C (Thesis advisor) / Westerhoff, Paul (Committee member) / Fox, Peter (Committee member) / Halden, Rolf (Committee member) / Hristovski, Kiril (Committee member) / Arizona State University (Publisher)
Created2014
Description
ABSTRACT études; written for violin ensemble, which include violin duets, trios, and quartets, are less numerous than solo études.; These works rarely go by the title "étude;," and have not been the focus of much scholarly research. Ensemble études; have much to offer students, teachers and composers, however, because they add an extra dimension to the learning, teaching, and composing processes. This document establishes the value of ensemble études; in pedagogy and explores applications of the repertoire currently available. Rather than focus on violin duets, the most common form of ensemble étude;, it mainly considers works for three and four violins without accompaniment. Concentrating on the pedagogical possibilities of studying études; in a group, this document introduces creative ways that works for violin ensemble can be used as both études; and performance pieces. The first two chapters explore the history and philosophy of the violin étude; and multiple-violin works, the practice of arranging of solo études; for multiple instruments, and the benefits of group learning and cooperative learning that distinguish ensemble étude; study from solo étude; study. The third chapter is an annotated survey of works for three and four violins without accompaniment, and serves as a pedagogical guide to some of the available repertoire. Representing a wide variety of styles, techniques and levels, it illuminates an historical association between violin ensemble works and pedagogy. The fourth chapter presents an original composition by the author, titled Variations on a Scottish Folk Song: étude; for Four Violins, with an explanation of the process and techniques used to create this ensemble étude.; This work is an example of the musical and technical integration essential to étude; study, and demonstrates various compositional traits that promote cooperative learning. Ensemble études; are valuable pedagogical tools that deserve wider exposure. It is my hope that the information and ideas about ensemble études; in this paper and the individual descriptions of the works presented will increase interest in and application of violin trios and quartets at the university level.
ContributorsLundell, Eva Rachel (Contributor) / Swartz, Jonathan (Thesis advisor) / Rockmaker, Jody (Committee member) / Buck, Nancy (Committee member) / Koonce, Frank (Committee member) / Norton, Kay (Committee member) / Arizona State University (Publisher)
Created2011
Description
This study examined attitudes and perspectives of classroom guitar students toward the reading of staff notation in music. The purpose of this qualitative research was to reveal these perceptions in the student's own words, and compare them to those of orchestra and band students of comparable experience. Forty-seven students from four suburban middle and high schools on the east coast were selected through purposeful sampling techniques. Research instruments included a Musical Background Questionnaire and a thirty-five question Student Survey. Follow-up interviews were conducted with students to clarify or expound upon collected data. Guitar, orchestra, and band teachers were interviewed in order to provide their perspectives on the issues discussed. The Student Survey featured a five-point Likert-type scale, which measured how much students agreed or disagreed with various statements pertaining to their feelings about music, note-reading, or their class at school. Collected data were coded and used to calculate mean scores, standard deviations, and percentages of students in agreement or disagreement with each statement. Interviews were audio recorded and transcribed into a word processing document for analysis. The study found that while a variety of perspectives exist within a typical guitar class, some students do not find note-reading to be necessary for the types of music they desire to learn. Other findings included a perceived lack of relevance toward the classical elements of the guitar programs in the schools, a lack of educational consistency between classroom curricula and private lesson objectives, and the general description of the struggle some guitarists experience with staff notation. Implications of the collected data were discussed, along with recommendations for better engaging these students.
ContributorsWard, Stephen Michael (Author) / Koonce, Frank (Thesis advisor) / Schmidt, Margaret (Thesis advisor) / Buck, Nancy (Committee member) / Rogers, Rodney (Committee member) / McLin, Katherine (Committee member) / Arizona State University (Publisher)
Created2011
Description
The overall goal of this dissertation is to advance understanding of biofilm reduction of oxidized contaminants in water and wastewater. Chapter 1 introduces the fundamentals of biological reduction of three oxidized contaminants (nitrate, perchlorate, and trichloriethene (TCE)) using two biofilm processes (hydrogen-based membrane biofilm reactors (MBfR) and packed-bed heterotrophic reactors (PBHR)), and it identifies the research objectives. Chapters 2 through 6 focus on nitrate removal using the MBfR and PBHR, while chapters 7 through 10 investigate simultaneous reduction of nitrate and another oxidized compound (perchlorate, sulfate, or TCE) in the MBfR. Chapter 11 summarizes the major findings of this research. Chapters 2 and 3 demonstrate nitrate removal in a groundwater and identify the maximum nitrate loadings using a pilot-scale MBfR and a pilot-scale PBHR, respectively. Chapter 4 compares the MBfR and the PBHR for denitrification of the same nitrate-contaminated groundwater. The comparison includes the maximum nitrate loading, the effluent water quality of the denitrification reactors, and the impact of post-treatment on water quality. Chapter 5 theoretically and experimentally demonstrates that the nitrate biomass-carrier surface loading, rather than the traditionally used empty bed contact time or nitrate volumetric loading, is the primary design parameter for heterotrophic denitrification. Chapter 6 constructs a pH-control model to predict pH, alkalinity, and precipitation potential in heterotrophic or hydrogen-based autotrophic denitrification reactors. Chapter 7 develops and uses steady-state permeation tests and a mathematical model to determine the hydrogen-permeation coefficients of three fibers commonly used in the MBfR. The coefficients are then used as inputs for the three models in Chapters 8-10. Chapter 8 develops a multispecies biofilm model for simultaneous reduction of nitrate and perchlorate in the MBfR. The model quantitatively and systematically explains how operating conditions affect nitrate and perchlorate reduction and biomass distribution via four mechanisms. Chapter 9 modifies the nitrate and perchlorate model into a nitrate and sulfate model and uses it to identify operating conditions corresponding to onset of sulfate reduction. Chapter 10 modifies the nitrate and perchlorate model into a nitrate and TCE model and uses it to investigate how operating conditions affect TCE reduction and accumulation of TCE reduction intermediates.
ContributorsTang, Youneng (Author) / Rittmann, Bruce E. (Thesis advisor) / Westerhoff, Paul (Committee member) / Krajmalnik-Brown, Rosa (Committee member) / Halden, Rolf (Committee member) / Arizona State University (Publisher)
Created2012
Description
Highly active in the fields of viola performance, composition, recording, and pedagogy, Lionel Tertis is known as one of the first and most influential career violists. Established in 1980, the Lionel Tertis International Viola Competition and Festival was founded in his honor and occurs triennially at the Isle of Man. While addressing facets of the professional violist with workshops, lectures, and masterclasses, this event provides a venue for competitive performers, acting as a platform for new viola repertoire.
Each competitor must prepare an extensive set of viola repertoire, among which is a compulsory piece for unaccompanied viola by an English composer. These commissioned works require the virtuosity and expression available within a contemporary musical language; this additionally challenges competitors to provide an artistic interpretation relatively untouched by tradition or common practice.
Although these pieces are written specifically for the competition, the commissioned works have the capacity to reach beyond the competition sphere and are highly programmable in most recital and solo performance settings. These pieces provide the contemporary violist with a greater selection of repertoire that displays idiomatic and expressive strengths of the viola.
My project commemorates the contributions of Lionel Tertis to the advancement of viola repertoire and performance with the study of works written a century post his prolific career. The secondary intent is to provide biographical information about each composer and to explore how these highly programmable works enrich the violist and their repertoire, ultimately bringing recognition to these new works for solo viola. Through biographical research, musical analysis, interviews and the recording process, I will provide a performer's analysis and supplemental recordings for three of these works: Darkness Draws In by David Matthews, Sonatine I by Roger Steptoe and Through a Limbeck by John Woolrich.
Each competitor must prepare an extensive set of viola repertoire, among which is a compulsory piece for unaccompanied viola by an English composer. These commissioned works require the virtuosity and expression available within a contemporary musical language; this additionally challenges competitors to provide an artistic interpretation relatively untouched by tradition or common practice.
Although these pieces are written specifically for the competition, the commissioned works have the capacity to reach beyond the competition sphere and are highly programmable in most recital and solo performance settings. These pieces provide the contemporary violist with a greater selection of repertoire that displays idiomatic and expressive strengths of the viola.
My project commemorates the contributions of Lionel Tertis to the advancement of viola repertoire and performance with the study of works written a century post his prolific career. The secondary intent is to provide biographical information about each composer and to explore how these highly programmable works enrich the violist and their repertoire, ultimately bringing recognition to these new works for solo viola. Through biographical research, musical analysis, interviews and the recording process, I will provide a performer's analysis and supplemental recordings for three of these works: Darkness Draws In by David Matthews, Sonatine I by Roger Steptoe and Through a Limbeck by John Woolrich.
ContributorsWuenschel, Allyson Kay (Author) / Buck, Nancy (Thesis advisor) / Carpenter, Ellon (Committee member) / Ryan, Russell (Committee member) / Arizona State University (Publisher)
Created2017
Description
This handbook is aimed to develop a violist’s technique as they move from Georg Philipp Telemann’s Concerto for Viola, Strings, and Basso Continuo in G Major, TWV 51: G9 and begin the Carl Stamitz's Viola Concerto in D Major, Op. 1. Ten etudes and related exercises introduce and highlight various techniques, providing a comprehensive and methodical transition from one concerto to the next. These etudes are based on fragments of the Stamitz Concerto in an effort to directly relate technical development with performance skills.
ContributorsChien, Shao-Chuan Sylvia (Author) / Buck, Nancy (Thesis advisor) / Rockmaker, Jody (Committee member) / Landschoot, Thomas (Committee member) / Arizona State University (Publisher)
Created2018
Description
This document is comprised of an arrangement and recording of Giuseppe Tartini’s “Devil’s Trill” Sonata for solo violin, and includes historical background, an exploration of Italian ornamentation, and a structural analysis. The original work was written for violin and basso continuo. The author was inspired to create this arrangement for solo violin based on accounts that Tartini liked to perform this work unaccompanied.
The first three chapters focus on events from Tartini’s early life that influenced his compositional style. Chapters four and five provide an overview of Italian ornamentation, and explore five documents that were used to support decisions in creating the arrangement: Giovanni Luca Conforto’s The Joy of Ornamentation; Giuseppe Tartini’s Traité des Agréments de la Musique; Letter to Signora Maddalena Lombardini; Regole; and L’Arte dell Arco. Chapter six provides a structural analysis of the Sonata. The appendices illustrate the process of creating the arrangement.
The arrangement takes into consideration the composite of the original solo and basso continuo parts. In addition, a set of realized ornaments is provided on an ossia staff. The recording includes both the primary arrangement, presented in each initial section, as well as the realized ornaments, presented in each repeated section.
The first three chapters focus on events from Tartini’s early life that influenced his compositional style. Chapters four and five provide an overview of Italian ornamentation, and explore five documents that were used to support decisions in creating the arrangement: Giovanni Luca Conforto’s The Joy of Ornamentation; Giuseppe Tartini’s Traité des Agréments de la Musique; Letter to Signora Maddalena Lombardini; Regole; and L’Arte dell Arco. Chapter six provides a structural analysis of the Sonata. The appendices illustrate the process of creating the arrangement.
The arrangement takes into consideration the composite of the original solo and basso continuo parts. In addition, a set of realized ornaments is provided on an ossia staff. The recording includes both the primary arrangement, presented in each initial section, as well as the realized ornaments, presented in each repeated section.
Contributorsda Cruz Ribeiro e Rodrigues, Christiano E (Author) / Swartz, Jonathan (Thesis advisor) / Buck, Nancy (Committee member) / Rogers, Rodney (Committee member) / Arizona State University (Publisher)
Created2019
Description
This research paper provides a revised version of viola alta compositions by
Hermann Ritter. These original compositions, written for viola alta, were published between 1878 and 1900. Without further reprint, these works are largely unknown by this generation of violists. Yet, these works are precious examples of viola alta repertoire from the late nineteenth century.
The viola alta was designed by Hermann Ritter with an instrumental length between 17 and 19 inches. Another version of this instrument was constructed with five strings, adding a high E-string. Higher pitches could then be played with relative ease in lower positions. Compositions for the viola alta often feature brilliant passages in the treble register and rarely showcase the sonority of the lower strings. Many of Ritter’s scores for the instrument are notated in the alto clef and contain numerous ledger lines. Due to the difficulty of reading the music and handling such a large instrument, the viola alta had a relatively short existence and its repertoire was soon forgotten.
Hermann Ritter actively promoted the viola alta during the late nineteenth century. His compositions featured the range of the instrument and captured the emotion and character of the late Romantic era. Ritter contributed a wealth of repertoire for the viola alta to increase its significance and importance. For today’s violist, it represents a body of work from the nineteenth century, and adds to the repertoire many wonderful, short, character pieces.
This document consists of a brief discussion of Hermann Ritter’s career and his contributions to the viola alta. Six of Ritter’s viola alta works are presented in order of difficulty with bowings and fingerings, along with a performer’s analysis and performance instructions. To aid ensemble issues, the revised version includes simplified piano parts. It is the author’s hope that this volume increases repertoire options for violists and becomes a valuable pedagogical resource.
Hermann Ritter. These original compositions, written for viola alta, were published between 1878 and 1900. Without further reprint, these works are largely unknown by this generation of violists. Yet, these works are precious examples of viola alta repertoire from the late nineteenth century.
The viola alta was designed by Hermann Ritter with an instrumental length between 17 and 19 inches. Another version of this instrument was constructed with five strings, adding a high E-string. Higher pitches could then be played with relative ease in lower positions. Compositions for the viola alta often feature brilliant passages in the treble register and rarely showcase the sonority of the lower strings. Many of Ritter’s scores for the instrument are notated in the alto clef and contain numerous ledger lines. Due to the difficulty of reading the music and handling such a large instrument, the viola alta had a relatively short existence and its repertoire was soon forgotten.
Hermann Ritter actively promoted the viola alta during the late nineteenth century. His compositions featured the range of the instrument and captured the emotion and character of the late Romantic era. Ritter contributed a wealth of repertoire for the viola alta to increase its significance and importance. For today’s violist, it represents a body of work from the nineteenth century, and adds to the repertoire many wonderful, short, character pieces.
This document consists of a brief discussion of Hermann Ritter’s career and his contributions to the viola alta. Six of Ritter’s viola alta works are presented in order of difficulty with bowings and fingerings, along with a performer’s analysis and performance instructions. To aid ensemble issues, the revised version includes simplified piano parts. It is the author’s hope that this volume increases repertoire options for violists and becomes a valuable pedagogical resource.
ContributorsChen, Yen-Fang (Author) / Buck, Nancy (Thesis advisor) / Rockmaker, Jody (Committee member) / Swartz, Jonathan (Committee member) / Arizona State University (Publisher)
Created2018