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Chemistry of 6-Monobrominated Indigo, MBI
Year of Dissertation:
6-monobrominated indigo, MBI, is a component of a historically important and the most expensive colorant, Tyrian Purple. The colorant is remarkably stable under the sun, in the air and after extensive washing with water. The color is still vivid after thousands of years. Even though it has such a high stability, MBI and Tyrian Purple have color changes from purple to blue upon temperature changes. This color change has been known for long to certain people, but the mechanism of the color change was unknown. Tyrian Purple also has recently attracted interests for applications towards semiconducting material due to its ambipolar property and high stacking structure and towards its biomedical applications. Though other chemicals in the colorant have been studied and analyzed well, MBI is the least studied and understood chemical. The full investigation of the chemistry of MBI has been conducted and reported in this study.
Nickel-catalyzed cross-coupling reactions involving secondary and tertiary alkyl nucleophiles
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NICKEL-CATALYZED CROSS-COUPLING REACTIONS INVOLVING SECONDARY AND TERTIARY ALKYL NUCLEOPHILES by Amruta Ajit Joshi Advisor: Prof. Mark R. Biscoe In the first chapter, introduction of transition metal-catalyzed cross-coupling reactions has been given. These transition metal-catalyzed C-C bond forming reactions have been used extensively in organic synthesis. Among them, C(sp2)-C(sp2) bond forming reactions have been widely studied over decades. More recently, some reports have demonstrated the use of C(sp3) nucleophiles and electrophiles in cross-coupling reactions. However, use of secondary and tertiary alkyl nucleophiles has remained a challenge due to competitive β-hydride elimination and slow transmetallation of bulky secondary and tertiary alkyl organometallic nucleophiles. In the second chapter, the first general nickel-catalyzed Negishi reaction for the cross-coupling of unactivated, acyclic secondary alkylzinc halides and aryl and hetero-aryl iodides has been reported. This process is the first to overcome the β-hydride elimination problem inherent to the use of the analogous palladium-catalyzed processes. This method is very general and tolerates a wide range of functional groups. A detailed study of the effect of salt additives on these reactions has also been presented. In the third chapter, this work has been extended to the use of tertiary alkyl nucleophiles and the first metal-catalyzed Kumada cross-coupling reaction of tertiary alkylmagnesium halides and aryl bromides/triflates has been reported. This reaction has very wide substrate scope, and vinyl bromides and vinyl chlorides can also be employed as electrophiles. Here, the effect of catalyst hydration on the reaction yield and selectivity has been demonstrated. In the fourth chapter, a mild palladium-catalyzed reaction for the monoborylation of primary alkyl halides using bis(pinacolato)diboron as the boron source has been reported. This reaction is very general and can accommodate a wide range of functional groups. To increase the utility of this process, the crude borylation product has been converted into the corresponding boronic acid, trifluoroborate salt and another boronic ester. Aditionally, bis(neopentylglycolato)diboron has also been employed as the boron source.
Exchanging Affect: The Migrant Domestic Workers Market in Turkey
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Since the second half of 1990's, Turkey has received a migration flow of women from the postsocialist countries of Eastern Europe, the Caucuses and Central Asia, into the domestic work sector. The demand for the migrant domestics is mainly for their live-in services, which also distinguishes them from the indigenous domestics since the latter prefer working strictly as live-outs. The migrants' willingness to work as live-in's has consequently caused them to be employed in three subfields of domestic work; care giving for the elderly, care giving for children and housekeeping in suburban houses. This research explores the emergence and expansion of "the migrant domestic workers market" as an ethnic niche in Turkey in the postsocialist period when migration and employment relations have formed a mutually fostering alliance. It argues that the migrant domestics of postsocialist origin are not demanded for an inherent ability. Rather the demand for their labor is a consequence of a capacity that they acquire by turning into transnational migrants. In this process, their subjectivity that was earlier shaped by an upbringing in a formerly socialist system also gets molded by a state of "migrancy". The latter then causes them to serve their employers in a distinct way that is characterized by a specific type of labor, which in this research is called "availability".
Piezoelectric Energy Harvesting From Fluid Flow
Huseyin Dogus Akaydin
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The conversion of the kinetic energy of a fluid into electrical energy through flow-induced vibrations on piezoelectric structures is investigated. "Aeroelectromechanics" of flow-powered piezoelectric harvesters is introduced, the efficiency components are delineated, and the figures of merit are defined. Wind tunnel tests were performed on two kinds of harvesters: i) A cantilevered piezoelectric beam in the wake of a circular cylinder, ii) A cantilevered piezoelectric beam carrying a tip mass on its free end. The comparison of the two revealed the prime effect of aeroelastic efficiency in total efficiency. A semi-analytical model to account for strain transfer from a passive substrate to a piezoelectric patch through an elastic bonding layer was developed. It was shown that, under certain conditions, the electric output of the piezoelectric harvesters can be predicted based on strain measurements on test models built without using piezoelectric materials. The potential of turbulent boundary layers for energy harvesting was also investigated. Two flexible piezoelectric beams of different lengths were tested at various distances off the wall of wind tunnel at different flow speeds. It was found out that the power output is maximal when the beam is within a certain wall-distance region inside the boundary layer, and that the size of this region is larger for the shorter beam. The interaction of a flexible piezoelectric beam with vortex rings was another topic investigated. Time-resolved PIV images were taken synchronously with strain, base-force and piezoelectric voltage data as a vortex ring travels over a piezoelectric beam. The dynamic tip deflection of the beam estimated using the PIV data in a potential flow solution was found comparable to the measured tip deflection. In addition to the experimental work, a computational framework for modeling aeroelectromechanical interactions was developed by integrating an electrical circuit analysis code to a flow simulation program through external scripting. The framework was applied for the case of a flexible piezoelectric beam in the wake of a cylinder. A reasonable agreement was obtained between the computer simulations and the experimental results.
Of home and other figments: The passage of exile in the Tibetan diaspora
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This dissertation used a study of lives approach to understand the stories told by four Tibetans who came to New York following the passage of the Immigration Act of 1990 when Tibetans first came to the United States in mass. Not unlike other diasporas in the world today, the transfer of the events, the stories, and in many cases, the wounds, of exile formatively shape the narrative hereafter of younger generations, though this phenomenon has been given little attention in the social sciences. This work asked: 1) What stories of exile are passed from one generation to another and what are the mechanisms of transmission within that passage? (2) How is home understood generationally? (3) And within the experience of exile, what are the possibilities for action in daily life? Looking across four life historical accounts, my analysis revealed that the stories my informants heard as they grew up can be grouped into the themes of death, survival, and hope. The stories they passed on to younger people in their lives took the form of bodily care, solitude, and discrimination. These stories moved through the narrative mechanisms of translation, silence, and interlocutory slippage with attention to a story's didactic, shaping features. Home was understood as an impossibility for those younger Tibetans with whom I spoke, whereas it was associated with death and decay for older Tibetans. However, generational differences were downplayed by considering exile as a noun (a status) and verb (the ongoing result of an event), which was rife with socio-economic implications. Action took the form of community involvement and its gesture, a commitment to education, and a cursory knowledge of politics. These forms of action were narrated through bearing witness, employing the subjunctive, and calling attention to the body to narrate what escaped words. This inquiry highlights the importance of stories in the experience of exile, as well as the mechanisms through which exile is narrated. Additionally, my analysis emphasizes a consideration of death and natality as central to the experience of exile, and explores the literal and metaphorical ways through which death and natality become narrative forces.
CRISIS, FORMULATION AND AUTOBIOGRAPHICAL INTIMACY IN 1950s AMERICA
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Crisis, Formulation, and Autobiographical Intimacy in 1950s America explores how critical circumstances of historical and personal significance can inspire and direct autobiographical production. I concentrate on Alfred Kazin's A Walker in the City (1951), Vladimir Nabokov's Speak, Memory (1967), and Robert Lowell's Life Studies (1959), three American autobiographies whose first or final versions were produced in the nineteen fifties, decade marked by a surge of autobiographical texts and genres in the United States and the emergence of autobiographical theory in France. Engaging with Robert Jay Lifton's theory of trauma, namely the concept of formulation, I investigate how the relationship between the self and the world is fostered in the wake of a crisis as reflected in autobiographical performance unfolding through drafting, meta-writing, revision, publication, and republication. As I trace the evolution of the texts, I find each author's persistent attempt to forge a connection to the multiple relational others, including the reader, implicated in the autobiographical act. I argue that the prospect and process of gaining this connection - at once troubling and rewarding - tend to stimulate writing and facilitate revision as the writers cross the threshold from the pre-war to the post-war world and grapple with the shifts occurring in their private lives. In the course of writing and re-writing their autobiographies, Kazin, Nabokov, and Lowell develop a special kind of closeness with their relational others that arises from the interrelated acts of identification, projection, and narration. Looking at autobiographical process (revision, textual versioning) rather than merely product (final text), I illustrate how these acts are enhanced, qualified, or reversed as they are repeated. They produce autobiographical intimacy: forged by various forms of interaction(s), it is a virtual space whereby participants of the autobiographical act foster communication, reciprocity, and potentially trust - productively or otherwise.
The Music and Multiple Identities of Kurdish Alevis from Turkey in Germany
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This dissertation investigates the experiences of Kurdish Alevis, currently living in Germany, who trace their background to locations within the boundaries of the Republic of Turkey. I argue that music has been a particularly important mode through which Kurdish Alevis in Germany have articulated collective histories and have fashioned narratives of belonging and multiple and sometimes contradictory identities. The subjects of my research are immigrants and refugees who are ethnically Kurdish and whose religion is Alevi, an Anatolian religion whose relations to both Sunni and Shi'a Islam are historically controversial. They speak Turkish along with Kurdish, in most cases are Turkish and German citizens living in and around Cologne, Germany, and have family members in Istanbul, Turkey. Kurdish Alevis struggled against being labeled with certain identities, such as Turkish and Muslim within the larger immigrant pool from Turkey. At the same time, many of them have striven for their collective identities, namely Kurdish and Alevi, primarily in the last two decades. Music has been an integral part of their efforts. I argue that, in the last two decades, a new transnational field has emerged for Kurdish Alevi immigrants and refugees in Germany and by extension in Turkey, opening spaces for realignment around various and fluctuating loyalties with respect to ethnic, political, and social modes of belonging. This work is an investigation of the music of this ethno-religious double minority group in their second and third homelands.
The People Behind the Presidential Bully Pulpit
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"The People Behind the Presidential Bully Pulpit" argues that civil servants best serve the interests of both the President of the United States and the American people as public affairs officers in the Department of the Treasury. Using interviews conducted with political appointees who served as Treasury spokespeople during the administrations of Presidents Barack Obama and George W. Bush, civil servants who served in public affairs for the Treasury, and Treasury reporters who interacted frequently with the government officials, the study finds that civil servants better advance the goals of the President in the press than the political appointees personally selected by the President. This is the case because civil servants have greater knowledge of the policies they advocate and because reporters apply greater skepticism to the arguments of political appointees because reporters assume that appointees are always attempting to advance political agendas - a phenomenon this study calls the "appointee discount." While scholars have previously argued that presidents accept the lower competence of appointees in order to attain their greater loyalty, this study suggests that no such tradeoff exists. It finds that political appointees and civil servants leak information to the press that does not serve the interests of the President with roughly the same frequency. The study also finds that civil servants better serve the interests of the American people in such roles. The study finds that neither political appointees nor civil servants in the Treasury's public affairs department are conducting the "permanent campaign" to build support for the President that White House aides have been accused of practicing, by governing based upon public opinion polls and appealing to the emotions, as opposed to the reason, of the American people. However, political appointees are significantly more likely to withhold information requested by reporters than civil servants.
Acculturation of children of Bangladeshi immigrants in New York City: Intergenerational perspectives and alternative trajectories
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This study explores the acculturation experiences of thirty-three Bangladeshi second generation youths in New York City through in depth interviews. The researcher has observed and recorded interactions between youths and parents in the natural setting of their homes. The findings of this qualitative study, conducted in the tradition of grounded theory, are presented in four analytic categories: crossroads of acculturation dividing immigrant parents and children; gendered socialization of Bangladeshi children in traditional patriarchal families; influence of New York City on acculturation of these children; and their ethnic self-identity trajectories and repertoires. These frameworks reveal how intentionality and secondary socialization impinge on intergenerational cultural continuity to transform new New Yorkers; unlike their parents, the children renounce ethnocentricity, native country affiliation, and patriarchal value system. Bangladeshi immigrant parents contribute to the city's increasing diversity by remaking the city through burgeoning ethnic enclaves, in which they hold fast to cultural traditions. In contrast, their children remake the city and the city remakes them. They embrace a plurality of perspectives and the values of an egalitarian society. Because all the young informants are New Yorkers, their acculturation experiences are shaped in a diverse and multi-ethnic setting. They contextualized these experiences in comparison with actual and potential second generation immigrant experiences in "the mid-west" or upstate New York, isolated from a vibrant ethnic enclave and multi-cultural community. The study has also developed mid-level theories: immigrant children's acculturation is attributed to push-pull factors, shift from primary to secondary socialization, and intentionality compared with parents. Bangladeshi girls question gendered socialization and reject their parent's role in contracting arranged marriages more so than the boys. They benefit from the protection of stringent parental oversight, while boys' freedoms lead, in some instances, to antisocial behavior. In addition, the length of children's self-identity trajectories is matched by the level of complexity in their identity repertoires. A key implication for social work practice is that Bangladeshi parents reject services from members of their own community because they do not want exposure of parent-child conflicts within the ethnic enclave. Community-based services are unlikely to benefit families who need to resolve intergenerational discord.
Studies in Volatility
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This dissertation consists of five chapters that focus on the price discovery role of equity markets and examine the evolution of intraday stock price volatility as a key measure of market quality. Using six differentiated measures of intraday volatility (that mostly focus on the opening half-hour of trading), all common stocks listed at three stock exchanges with varying levels of fragmentation are analyzed: NYSE and NASDAQ stocks over the period 1993-2012, and Istanbul Stock Exchange (ISE) stocks over the period 2000-2011. The results on the evolution of intraday volatility presented in Chapters 2 and 3 indicate the following: In 1993, opening period volatility for NYSE listed stocks was considerably lower than it was for NASDAQ stocks. Over the years that followed, NASDAQ's opening volatility fluctuated widely, but has exhibited neither an upward nor a downward trend. For the NYSE, on the other hand, opening volatility has risen appreciably; now, and in recent years, its pattern closely matches that of NASDAQ. ISE listed stocks exhibited much higher intraday volatility at the beginning of the sample period (in 2000), but it decreased over the next twelve years. Recognizing the differences in the evolution of fragmentation in these three markets, Chapter 4 presents an analysis of the relation between stock-level fragmentation and the corresponding intraday volatility for the U.S. stocks. The chapter documents a positive and persistent relationship between fragmentation and opening period volatility. In light of the results presented in this dissertation, it is important for market participants to recognize the complexities of the price discovery process in the marketplace and to target on developing more efficient trading mechanisms that will improve the quality of prices. These improvements will benefit the participants in a market as well as the broader economy that they constitute.