Alumni Dissertations

 

Alumni Dissertations

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  • Solid State Nuclear Magnetic Resonance Investigations of Advanced Energy Materials

    Author:
    George Bennett
    Year of Dissertation:
    2009
    Program:
    Physics
    Advisor:
    Steve Greenbaum
    Abstract:

    In order to better understand the physical electrochemical changes that take place in lithium ion batteries and asymmetric hybrid supercapacitors solid state nuclear magnetic resonance (NMR) spectroscopy has been useful to probe and identify changes on the atomic and molecular level. NMR is used to characterize the local environment and investigate the dynamical properties of materials used in electrochemical storage devices (ESD). NMR investigations was used to better understand the chemical composition of the solid electrolyte interphase which form on the negative and positive electrodes of lithium batteries as well as identify the breakdown products that occur in the operation of the asymmetric hybrid supercapacitors. The use of nano-structured particles in the development of new materials causes changes in the electrical, structural and other material properties. NMR was used to investigate the affects of fluorinated and non fluorinated single wall nanotubes (SWNT). In this thesis three experiments were performed using solid state NMR samples to better characterize them. The electrochemical reactions of a lithium ion battery determine its operational profile. Numerous means have been employed to enhance battery cycle life and operating temperature range. One primary means is the choice and makeup of the electrolyte. This study focuses on the characteristics of the solid electrolyte interphase (SEI) that is formed on the electrodes surface during the charge discharge cycle. The electrolyte in this study was altered with several additives in order to determine the influence of the additives on SEI formation as well as the intercalation and de-intercalation of lithium ions in the electrodes. 7Li NMR studies where used to characterize the SEI and its composition. Solid state NMR studies of the carbon enriched acetonitrile electrolyte in a nonaqueous asymmetric hybrid supercapacitor were performed. Magic angle spinning (MAS) coupled with cross polarization NMR techniques were used to determine what effects 200 ppm of intentionally added water would have on the decomposition of the acetonitrile. The resultant NMR spectra yielded several prominent peaks which were assigned to acetamide, glycolonitrile, formaldehyde and other lithium carbon derivatives. The aforementioned decomposition products are a believed to be a result of the acetonitrile being hydrolyzed as well as its interaction with the lithium salt. The decomposition products are deposited on electrode surface leading to operation changes in the life of the supercapacitors. The information gained from the NMR studies may be beneficial understanding the supercapacitor operation and aid in future design. Carbon nanotubes are used to enhance structural stability and performance. In this experiment NMR is used to determine if the addition of nanotubes to two types of polymer matrix changes the structural stiffness and motional dynamics. The polymers studied by direct 1H NMR observations are Polybutadiene (PB) and Polyisobutylene (PIB). PB and PIB with single walled carbon nanotubes (SWNT) as well as functionalized with fluorine (F) produce significantly stronger composites as compared to composites without SWNT.

  • EVOLUTION AND ETHICS

    Author:
    FRANKLIN BENNETT
    Year of Dissertation:
    2014
    Program:
    Philosophy
    Advisor:
    STEVEN CAHN
    Abstract:

    Does evolution inform the ancient debate about the roles that instinct (emotion/passion/sentiment/feeling) and reason do and/or should play in how we decide what to do? Evolutionary ethicists typically adopt Darwinism as a suitable explanation for evolution, and on that basis draw conclusions about moral epistemology. However, if Darwinism is to be offered as a premise from which conclusions about moral epistemology are drawn, in order to assess such arguments we must assess that premise. This reveals the highly speculative and metaphysical quality of our theoretical explanations for how evolution happens. Clarifying that helps to facilitate an assessment of the epistemological claims of evolutionary ethicists. There are four general ways that instinct and reason can function in moral deliberation: descriptive instinctivism asserts that moral deliberation is necessarily a matter of instincts because control of the instincts by our faculty of reason is regarded (descriptively) as impossible; descriptive rationalism asserts that moral deliberation is necessarily a matter of reasoning, which (descriptively) must control instinct; prescriptive instinctivism asserts that moral deliberation can involve both rationality and instinct but prescribes following our instincts; prescriptive rationalism also asserts that deliberation can be either instinctive or rational but prescribes following reason. Micheal Ruse (2012), Peter Singer (2011), and Philip Kitcher (2011) each adopt Darwinism and on that basis arrive at descriptive instinctivism, descriptive rationalism, and prescriptive instinctivism, respectively. Our current level of understanding about evolution implies that prescriptive rationalism is a more practical approach to ethical deliberation than the other three alternatives described. Evolution can inform moral epistemology, but only very generally by helping to inform us of what we can justifiably believe about ourselves and nature.

  • Europium Complexes as Probes for Biological and Materials applications

    Author:
    Laurence Bensaid-Geyer
    Year of Dissertation:
    2009
    Program:
    Chemistry
    Advisor:
    Lynn Francesconi
    Abstract:

    Europium is a widely used lanthanide due to its emission in the visible region and its long life time. It is often complexed with ligands in order to serve different purposes in various domains: these complexes can be used as photostable biological probes but also as photoelectronic devices. This thesis interest will lie on both aspects. In chapter 2, we focused on europium phosphonates for targeting bone cancer. As we look at the adsorption of europium phosphonate to bone, possible scenario can take place: the complex can adsorb to the bone and/or the europium can transchelate from the ligand. If the europium transchelate, we looked at the possibility of a europium incorporation into the hydroxyapatite (HA) structure. We prove the presence of europium within the HA structure using various analytical and spectroscopic methods such as elemental analysis, X&ndashray diffraction (XRD), Infra-red (IR), luminescence studies, X&ndashray absorption fine structure (XAFS), and other spectroscopic analysis (SEM, BSE and EDS). In another part, the actual adsorption of europium phosphonate onto HA surface was studied. The adsorption was demonstrated based on luminescence studies showing a change of europium environment. In chapter 3, solution behavior of lanthanide complexes of the &alpha2&ndashP2W17O6110- ligand was reported to identify trends that will facilitate rational synthesis of hybrid organic lanthanide polyoxometalate complexes. Based on 31P NMR studies, the equilibrium between the 1:1 and the 1:2 species, that was observed by Pope for the Ce(III) analog is prevalent for the early-mid lanthanides. This equilibrium is slightly dependent on pH but seems to be very much influenced by larger poorly hydrated cations which appear to favor the 1:2 species for the early to mid lanthanides while they do not appear to influence the equilibrium for the later lanthanides. For all counterions, we found the 1:1 species stable with no trace of the 1:2 species. Finally, in chapter 4, we investigated Eu&alpha1&ndashP2W17O617- (EuPOM) for a layer by layer deposition application with Zn(phen)32+ (Zn(phen)) and its potential as a electroluminescence device. The depositions were monitored by UV-vis. We successfully fabricated multilayer film via electrostatic interaction between the polyanion EuPOM7- and the polycation Zn(phen)32+ until reaching four bilayers when the layers appeared to strip off. Also luminescence studies showed that the multilayer film demonstrated an effective luminescence activity due to the energy transfer through space from the phenanthroline to the europium ion.

  • Policy Partners in the Neoliberal Age: Corresponding School and Prison Reforms Since 1970

    Author:
    Jeremy Benson
    Year of Dissertation:
    2014
    Program:
    Urban Education
    Advisor:
    Ira Shor
    Abstract:

    This dissertation is a comparative policy study of changes in education and incarceration of the past 40 years. Following national and global trends, New York City saw public school and carceral policies converge as the city experienced massive deindustrialization and governmental cutbacks while its political economy shifted to one driven by finance, investment, real estate, and the growth of a low-wage service sector. These changes dramatically increased economic inequality across racial lines, and spurred the intimate linkage of public education and state incarceration as institutional tools for the mass management of low-income communities of color. Following from a growing policy debate in education and criminal justice around the "school-to-prison pipeline," this study analyzes the emergence and structure of correspondence in these two major social sectors. This multiscalar research draws on critical policy analysis and critical discourse analysis to examine federal and state policy vis-à-vis case studies of local charter school and drug court reforms. Findings include correspondence in the implementation of data-driven managerial practices and representations, the extension of private nonprofit and foundation influence on policy, and the (re)production and circulation of what Melamed (2006) terms official antiracisms- knowledge systems which deracialize inequality on the one hand, while constructing neoliberal subject positions amenable to racialized processes of disinvestment, dispossession, and discipline on the other.

  • The Effects of Cover, Copy and Compare, Performance Feedback and Rewards on the Mathematical Calculation Skills of Students Identified with Math Difficulty

    Author:
    Geetal Benson
    Year of Dissertation:
    2013
    Program:
    Educational Psychology
    Advisor:
    Georgiana Tryon
    Abstract:

    This study examined the isolated effects of Cover, Copy and Compare (CCC) and the effects of CCC paired with performance feedback (CCC + PF) and rewards (CCC + RW) on the mathematical calculation skills of first grade students identified with math difficulty. Four research questions were addressed in this study. 1. Does Cover, Copy, and Compare increase first grade students' fluency in addition and subtraction calculation skills? 2. Does Cover, Copy and Compare paired with Performance Feedback have a higher rate of increase of first grade students' fluency in addition and subtraction calculation skills when compared to Cover, Copy, and Compare alone? 3. Does Cover-Copy-Compare paired with a Reward have a higher rate of increase of first grade students' fluency in mathematics calculation skills when compared with Cover, Copy, and Compare in isolation or Cover, Copy, and Compare paired with Performance Feedback? 4. Does Cover, Copy, and Compare increase first grade students' fluency in addition and subtraction skills at a higher rate than a control receiving no intervention? Eight first-grade students enrolled in General Education in an elementary school in a low-socioeconomic community within a major city in the Eastern United States were identified with Math Difficulty through a curriculum-based measure (CBM), and were the participants in the study. The students were randomly assigned to one of four treatment conditions: CCC, CCC + PF, CCC + RW and control. An alternating treatment design was used following an assessment of baseline levels that were determined using a CBM probe. The students received the interventions in both addition and subtraction operations over the course of 10 weeks. Rates of digits correct per minute (DCPM) and errors per minute (EPM) were the dependent measures used to indicate gains in calculation skills. Overall, the results of the study indicated that CCC produced significant decreases in EPM when compared with baseline performance and modest gains in DCPM. Adding PF or RW to CCC did not increase the power of the CCC intervention as hypothesized, although it produced faster response times in some students. The study replicated previous research by demonstrating the CCC is a sound method for improving academic skills.

  • DOMINICAN GAGÁ MUSIC AND DANCE: THE REMAKING OF A SPIRITUAL PERFORMANCE IN THE CITY OF NEW YORK

    Author:
    Marimer Berberena
    Year of Dissertation:
    2014
    Program:
    Liberal Studies
    Advisor:
    Ana Ramos-Zayas
    Abstract:

    This study analyzed the Haitian-Dominican spiritual and cultural expression of Gagá in New York City through the group Gagá Pa'l Pueblo (GPP). Text analysis, participant observation, and qualitative analysis of interviews with twelve participants in this activity were used to conduct this study. I demonstrate the existence of a transnational intergenerational and interethnic sociocultural interaction that is simultaneously public and private, ritualistic and entertaining, secular and spiritual. I argue that it is not a matter of putting Gagá in a spiritual-secular dichotomy, but rather about understanding that even if GPP is not a true reflection of what Gagá is in the Dominican Republic, it satisfies a sociopolitical, cultural and spiritual need among many Dominicans that live in New York City. GPP is, for instance, a place of spiritual-cultural transmission that embodies a memory and a history of hope and resistance for present and future generations.

  • A Holistic Approach to Representationalism

    Author:
    Jacob Berger
    Year of Dissertation:
    2013
    Program:
    Philosophy
    Advisor:
    Jesse Prinz
    Abstract:

    Perhaps the most promising account of the qualitative character of experience available is representationalism--the view that the qualitative character of a mental state is identical with (or supervenes on) that state's representational properties. According to representationalism, for example, the reddish qualitative character of a perception is (or is determined by) the property of the state's qualitatively representing red. But representationalism is incomplete without an account of how experiences represent what they do--that is, an account of the psychosemantics of qualitative content. To date, most representationalists have endorsed versions of so-called tracking theories of content, according to which a state represents a property just in case the state tracks that property. Such views are atomistic insofar as a state's content does not depend on its relations to other mental states. Versions of representationalism which depend upon such atomistic psychosemantics are, however, open to criticism. Some representationalists have therefore concluded that qualitative representation is primitive or resists reductive explanation. But this reaction may be too hasty. This dissertation develops a form of reductive representationalism according to which qualitative content is individuated in a holistic way. To develop this view, Chapter 1 addresses introductory issues regarding qualitative character and representation. Chapter 2 argues that standard forms of representationalism of the sort defended by Fred Dretske, William Lycan, and Michael Tye fail primarily because of theiratomistic approach to qualitative content. Recently, some representationalists have offered more sophisticated versions of the view, principally to accommodate phenomena such as undetectable quality inversion. Chapter 3 argues that these more complex accounts--including Sydney Shoemaker's dispositionalist representationalism and David Chalmers's Fregean representationalism--are unworkable. One might think that the failures of these views suggest that the chief rival to representationalism, the traditional qualia theory which holds that there are nonrepresentational qualitative aspects of perceptions, is correct. Chapter 4 argues that such a qualia theory is problematic because it cannot provide an account of our knowledge of qualia, even from the first-person perspective. In light of these considerations, Chapter 5 proposes a version of representationalism wherein qualitative content is individuated in a holistic way. This holistic theory of qualitative content--what is dubbed here `perceptual-role semantics'--builds upon a burgeoning theory of qualitative character, versions of which have been defended by, among others, Austen Clark, David Lewis, David Rosenthal, and Shoemaker. On the view developed, a qualitative state's content is determined by its relative location in a space of states that matches the corresponding quality spaces of perceptible properties to which those qualitative states provide access. For example, an experience of red represents red because the experience occupies a location within a space of experiences of color that corresponds to the location occupied by red within the quality space of colors. The resultant holistic version of representationalism avoids the problems that plague other versions of it, resolves a host of philosophical puzzles about qualitative character, fits with a range of recent empirical findings about perception, and opens the phenomena up to fruitful further study.

  • A Comparison of Vocabulary Learning From Joint Reading of Narrative and Informational Books With Dual Language Learner Children

    Author:
    Deborah Bergman Deitcher
    Year of Dissertation:
    2014
    Program:
    Educational Psychology
    Advisor:
    Helen Johnson
    Abstract:

    Abstract A Comparison of Vocabulary Learning From Joint Reading of Narrative and Informational Books With Dual Language Learner Children By: Deborah Bergman Deitcher Advisor: Professor Helen L. Johnson This study examined joint reading of narrative and informational texts in the home setting, between parents and their English-Hebrew dual language learning preschool children. Parent-child dyads were video-recorded while reading two sets of books; each set contained one narrative and one informational text on the same theme. Children's target word learning of 48 target words (12 words per book) of varying difficulty levels was measured from pretest to posttest. Results showed that children learned target words at both the receptive and expressive levels, with scores nearly tripling from pretest to posttest at the expressive level. Child's age, prior vocabulary knowledge, and target word difficulty level were significantly predictive of children's receptive word learning. Age, number of years the child was in Israel, prior vocabulary knowledge, and target word difficulty level were significantly predictive of children's expressive word learning. Contrary to expectation, book genre was not significantly predictive of word learning. However, parent book reading style differed by genre, with more overall talk, and nearly twice the number of the following elements occurring during readings of informational texts: references to vocabulary words, questions, text-to-text and text-to-reader references, restatements, and elaborations. Educational implications are discussed.

  • The Effects Of Certain And Uncertain Reinforcement Procedures On The Quiz Submission And Performance Of College Students

    Author:
    Melody Berkovits
    Year of Dissertation:
    2011
    Program:
    Psychology
    Advisor:
    Alicia Alvero
    Abstract:

    College instructors often provide homework so that their students can review class material; however some students do not take advantage of these review opportunities. This study compared the effects of a certain reward and a lottery reward on the quiz submission rates and accuracy of 112 college students. In Baseline, quizzes were for practice only and had no programmed contingency; in the Certain condition, two extra credit points were available for submission of a perfect quiz; and in the Lottery condition, students who submitted a perfect quiz were entered into a lottery with one winner (actual probability varied) for two points of extra credit. Submission rates averaged 36.50% for Baseline, 62.00% for Certain and 51.67% for Lottery. A one-way repeated measures ANOVA, followed by Fisher's LSD, found the differences in submission rates between all conditions to be significant at the .0001 level. Accuracy rates averaged 82.82% for Baseline, 93.80% for Certain and 93.99% for Lottery. A one-way repeated measures ANOVA, followed by Fisher's LSD found the mean score for the Baseline condition to be significantly lower than the mean scores for the Certain and Lottery conditions (p < .01), but did not find a significant difference between the latter two conditions (p < .05). This study demonstrates that when all other factors (e.g. magnitude) are equal, certain rewards are more effective than lottery rewards at increasing quiz submissions. It is possible that the lottery was less effective than the certain reward, due to the uncertainty (indirect contingency) inherent in the Lottery condition. These results have implications for business settings that use lottery rewards in an attempt to motivate a large number of employees at low costs. Future research should examine the roles of magnitude, probability and contingency in predicting the relative effectiveness of a lottery reward.

  • Discrimination of tone contrasts in Mandarin disyllables by naive American English listeners

    Author:
    Shari Berkowitz
    Year of Dissertation:
    2010
    Program:
    Speech & Hearing Sciences
    Advisor:
    Winifred Strange
    Abstract:

    The present study examined the perception of Mandarin disyllabic tones by inexperienced American English speakers. Participants heard two naturally-produced Mandarin disyllables, and indicated if the two were the same or different. A small native Mandarin-speaking control group participated as well. All 21 possible Mandarin contrasts where the initial syllable varied but the final syllable stayed the same were tested. Acoustic analysis was performed on the stimuli under study. Mandarin subjects scored at ceiling on all contrasts. American English subjects performed poorly on contrasts where the difference in mean F0 was small, or where the difference in the offset F0 of the first syllable was small. They also performed poorly when the difference in slope of the final syllable was small. Previous research has proposed that American English listeners attend primarily to the height difference between two tone stimuli, but here they attended to height in the first syllable and contour in the second syllable.