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Rahmat, Meysam. "Carbon nanotube - polymer interaction in nanocomposites." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=104648.
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Carbon nanotube–polymer nanocomposites have been the centre of intense studies for the past few years. With the superior properties of carbon nanotubes and the flexibility of polymers for different applications, extremely high expectations were set for this class of nanocomposites. Modelling studies showed significant potential, but the experimental investigations faced strict challenges to reach the predicted values. One of the main challenges is to obtain the optimum interaction between the nanotubes and the polymer matrix. The interaction influences the dispersion of nanotubes in the polymer and affects the overall properties of the nanocomposite. Therefore, the main objective of this research was to study the carbon nanotube–polymer interaction in nanocomposites. Based on a comprehensive review of the literature, molecular dynamics and atomic force microscopy were selected as the modelling and experimental techniques to study the interaction. In the modelling section, the interfacial properties of a single-walled carbon nanotube–poly(methyl methacrylate) nanocomposite were obtained through a three-phase simulation of a pull-out test. An interfacial binding energy of 0.39 kcal/molÅ2 was obtained from molecular dynamics simulation. On the other hand, in the experimental section, stepwise discretization method was proposed as a novel technique of interaction measurement using atomic force microscopy. Furthermore, a new interaction parameter, called interaction stress, was introduced to evaluate the interaction quality in nanocomposites. The stepwise discretization method was applied to a single-walled carbon nanotube–poly(methyl methacrylate) nanocomposite and a maximum interaction stress of 7 MPa was obtained. The results were, then, applied to classical contact theory and a nanoscale contact theory was developed. Furthermore, the interaction stress data were input to coarse grain simulations to obtain the interfacial properties of the nanocomposites. This new approach benefited from the flexibility of the coarse grain method and the reliability of the experimental data obtained from atomic force microscopy. Based on the results of the coarse grain simulations, the interfacial binding energy of a single-walled carbon nanotube–poly(methyl methacrylate) nanocomposite was estimated as 0.44 kcal/molÅ2. This value was then compared with the interfacial binding energy obtained from molecular dynamics results (i.e., 0.39 kcal/molÅ2). The good agreement between the results of modelling and experimental approaches demonstrated the validity of the work and the robustness of the proposed methods and parameters.Les nanocomposites avec des polymères renforcés de nanotubes de carbone ont été le centre d'attention de nombreuses études dans les dernières années. Les propriétés supérieures des nanotubes de carbone et la flexibilité des polymères à être utilisés dans de diverses applications ont créé de grandes attentes pour cette classe de nanocomposites. Des études de modélisation ont démontré un fort potentiel pour ces matériaux, cependant la validation expérimentale de ces propriétés prédites reste un défi. Une des principales difficultés est l'obtention d'une interaction optimale entre les nanotubes et la matrice polymère. Cette interaction influence la dispersion des nanotubes dans le polymère et affecte les propriétés globales du nanocomposite. De ce fait, l'objectif principal de ce travail de recherche a été l'étude de l'interaction entre les nanotubes de carbone et le polymère dans les nanocomposites. A partir d'une revue détaillée de la littérature, la méthode de dynamique moléculaire et la microscopie à force atomique ont été choisies comme techniques numériques et expérimentales pour étudier l'interaction. Dans la partie de modélisation, les propriétés d'interface d'un nanotube à paroi simple avec du poly(methyl methacrylate) ont été obtenues à partir d'une simulation d'un test d'arrachement en trois phases. Une énergie de liaison d'interface de 0.39 kcal/molÅ2 a été calculée par la simulation de dynamique moléculaire. Dans la section expérimentale, une méthode de discrétisation par étapes a été proposée en tant que nouvelle technique de mesure de l'interaction par microscopie à force atomique. De plus, un nouvel paramètre d'interaction, appelé contrainte d'interaction, a été introduit pour évaluer la qualité de l'interaction dans les nanocomposites. La méthode de discrétisation par étapes a été utilisée pour le nanocomposite de poly(methyl methacrylate) avec un nanotube de carbone à paroi simple, et une interaction maximale de contrainte de 7 MPa a été obtenue. Les résultats ont été ensuite utilisés pour la théorie classique de contact et une théorie de contact à l'échelle nano. Les données sur les interactions de contraintes ont été aussi utilisées comme entrées pour des simulations de dynamique moléculaire «gros grains» afin d'obtenir les propriétés d'interface des nanocomposites. Cette nouvelle approche bénéficie de la flexibilité de la méthode de dynamique moléculaire «gros grains» et de la fiabilité des données expérimentales obtenues par la microscopie à force atomique. À partir des résultats de la méthode de dynamique moléculaire «gros grains», l'énergie de liaison d'interface d'un nanocomposite de nanotube de carbone–poly(methyl methacrylate) a été estimée à 0.44 kcal/molÅ2. Cette valeur a été comparée à l'énergie de liaison d'interface obtenue par la méthode de dynamique moléculaire (i.e., 0.39 kcal/molÅ2). La bonne corrélation entre les résultats basés sur des approches numériques et expérimentales démontre la validité de cette étude ainsi que la robustesse des méthodes proposées et des paramètres développés.
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Alam, Md Kawsar. "Interaction of electron beams with carbon nanotubes." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/36530.
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Carbon nanotubes have great potential for nanoscale devices. Previous studies have shown the prospects of carbon nanotubes as stable, low-voltage electron emitters for vacuum electronic applications. Yet, their electron emission mechanisms are far from being fully understood. For example, it is not completely clear how nanotubes interact with an external electron beam and generate secondary electrons. In addition to its fundamental scientific importance, understanding these mechanisms and properties will facilitate the engineering of nanotube-based devices for applications such as vacuum transistors, electron multipliers, X-ray devices for medical imaging, etc.
This thesis presents an experimental and theoretical investigation into the interaction of electron beams with carbon nanotubes. First-principles simulations are carried out to qualitatively analyze the possible direct interaction mechanisms of electron beams with nanotubes. An experimental study of electron yield (total, backscattered and secondary electron yields) from individual nanotubes and collections of nanotubes is reported. The experiments reveal low secondary electron yield from individual nanotubes. A different backscattered electron emission behaviour compared to that in bulk materials is observed in nanotube forests due to unusually high electron penetration range in them.
A semi-empirical Monte Carlo model for the interaction of electron beams with collections of nanotubes is presented. Physically-based empirical parameters are derived from the experimental data. The secondary electron yield from individual nanotubes is first investigated in the light of the commonly used energy loss model for solids. Finally, the problems of using the traditional models for individual nanotubes are identified and an approach to modeling secondary and backscattered electron emission from such nanostructures is presented.
The experiments and analysis presented in this thesis provide a platform for investigating backscattered and secondary electron emission also from nanostructures other than nanotubes.
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Lourenço, Leandro Miguel de Oliveira. "Phthalocyanines : interaction with carbon structures and as PDT agents." Doctoral thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/13125.
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Doutoramento em QuímicaThis dissertation describes the synthesis and characterization of different phthalocyanine (Pc) derivatives, as well as some porphyrins (Pors), for supramolecular interaction with different carbon nanostructures, to evaluate their potential application in electronic nanodevices. Likewise, it is also reported the preparation and biological evaluation of interesting phthalocyanine conjugates for cancer photodynamic therapy (PDT) and microorganisms photodynamic inactivation (PDI). The phthalonitrile precursors were prepared from commercial phthalonitriles by nucleophilic substitution of -NO2, -Cl, or -F groups, present in the phthalonitrile core, by thiol or pyridyl units. After the synthesis of these phthalonitriles, the corresponding Pcs were prepared by ciclotetramerization using a metallic salt as template at high temperatures. A second strategy involved the postfunctionalization of hexadecafluorophthalocyaninato zinc(II) through the adequate substituents of mercaptopyridine or cyclodextrin units on the macrocycle periphery. The different compounds were structurally characterized by diverse spectroscopic techniques, namely 1H, 13C and 19F nuclear magnetic resonance spectroscopies (attending the elemental composition of each structure); absorption and emission spectroscopy, and mass spectrometry. For the specific photophysical studies were also used electrochemical characterization, femtosecond and raman spectroscopy, transmission electron and atomic force microscopy. It was highlighted the noncovalent derivatisation of carbon nanostructures, mainly single wall carbon nanotubes (SWNT) and graphene nanosheets with the prepared Pc conjugates to study the photophysical properties of these supramolecular nanoassemblies. Also, from pyridyl-Pors and ruthenium phthalocyanines (RuPcs) were performed Por-RuPcs arrays via coordination chemistry. The results obtained of the novel supramolecular assemblies showed interesting electron donor-acceptor interactions and might be considered attractive candidates for nanotechnological devices. On the other hand, the amphiphilic phthalocyanine-cyclodextrin (Pc-CD) conjugates were tested in biological trials to assess their ability to inhibit UMUC- 3 human bladder cancer cells. The results obtained demonstrated that these photoactive conjugates are highly phototoxic against human bladder cancer cells and could be applied as promising PDT drugs.
Esta dissertação descreve a síntese e caracterização de diferentes derivados de ftalocianina (Pc), assim como de algumas porfirinas (Pors), para interação supramolecular com diferentes nanoestruturas de carbono para potencial aplicação em nanodispositivos eletrónicos. Igualmente, é também reportado a preparação e avaliação biológica de interessantes conjugados de Pc para a terapia fotodinâmica (PDT) de cancro e para a fotoinativação de microrganismos (PDI). Neste trabalho científico são discutidas as propriedades gerais das Pcs e metodologias sintéticas usadas na sua preparação, bem como algumas das suas importantes aplicações. Os precursores ftalonitrilo foram preparados a partir de ftalonitrilos comerciais por substituições nucleofílicas de grupos -NO2, -Cl ou -F, presentes no núcleo ftalonitrilo, por unidades tiol ou piridilo. As correspondentes Pcs foram preparadas por ciclotetramerização dos ftalonitrilos, previamente sintetizados, na presença de um sal metálico a temperaturas elevadas. Uma segunda estratégia envolveu a pós-funcionalização na periferia do macrociclo da ftalocianina hexadecafluor de zinco(II) com unidades de mercaptopiridina ou ciclodextrina. Os diferentes compostos foram caracterizados estruturalmente por diversas técnicas espectroscópicas, nomeadamente espectroscopia de ressonância magnética nuclear de 1H, 13C e 19F (atendendo à composição elementar de cada estrutura), espectroscopia de absorção e de emissão, e espectrometria de massa. Para estudos fotofísicos específicos foram também usadas a caracterização electroquímica, espectroscopia de femtossegundo e raman, microscopia de transmissão eletrónica e de força atómica. Foi realizado a derivatização não covalente de nanoestruturas de carbono, principalmente nanotubos de carbono de parede simples (SWNT) e nanofolhas de grafeno, com os conjugados de ftalocianina preparados, para dessa forma estudar as propriedades fotofísicas dessas nanoassembleias supramoleculares. Também, a partir de Pors-piridilo e ftalocianinas de ruténio (RuPcs) foram realizadas matrizes de Por-RuPcs via química de coordenação. Os resultados obtidos mostraram interessantes interações eletrónicas doador-aceitador e podem ser considerados candidatos atrativos para diversos dispositivos nanotecnológicos. Por outro lado, os conjugados anfifílicos de ftalocianina-ciclodextrina (Pc-CD) foram testados em ensaios biológicos para avaliar a sua capacidade de inibir células cancerígenas UM-UC-3 da bexiga humana. Os resultados obtidos demonstraram que estes conjugados fotoativos são altamente fototóxicos contra este tipo de células, mostrando-se bastante promissores como agentes em PDT.
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Barman, Poulami. "The interaction of peptides with functionalized carbon nanotubes /." Online version of thesis, 2009. http://hdl.handle.net/1850/8688.
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Cavan, Graeme Patrick. "Interaction of carbon and nitrogen metabolism in Schizosaccharomyces pombe." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259573.
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James, Matthew Philip William. "The interaction of electromagnetic radiation with carbon nanotube fibres." Thesis, University of Cambridge, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.707916.
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Hofmann, Mario. "Synthesis and fluid interaction of ultra long carbon nanotubes." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/46606.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2009.MIT Barker Library copy printed in pages.
Includes bibliographical references (leaves 49-50).
The successful integration for carbon nanotubes in future electronic applications relies on advances in their synthesis. In this work optimization of growth parameters was conducted to obtain ultra long carbon nanotubes. Their morphology was analyzed by means of different techniques and evidence of the occurrence of nanotube bundles was found. The effect of varying several parameters on the morphology of the obtained nanotubes was investigated and successful growth of ultra long nanotubes was achieved. The settling process, i.e. the sinking of the nanotubes to the substrate, of those nanotubes was investigated by a newly developed in-situ rotation tool and statistical data for their behavior during growth was obtained.
by Mario Hofmann.
S.M.
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Ye, Zhou. "Mechanism and the Effect of Microwave-Carbon Nanotube Interaction." Thesis, University of North Texas, 2005. https://digital.library.unt.edu/ark:/67531/metadc4919/.
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A series of experimental results about unusual heating of carbon nanotubes by microwaves is analyzed in this dissertation. Two of vibration types, cantilever type (one end is fixed and the other one end is free), the second type is both ends are fixed, have been studied by other people. A third type of forced vibration of carbon nanotubes under an alternating electromagnetic field is examined in this paper. Heating of carbon nanotubes (CNTs) by microwaves is described in terms of nonlinear dynamics of a vibrating nanotube. Results from the model provide a way to understand several observations that have been made. It is shown that transverse vibrations of CNTs during microwave irradiation can be attributed to transverse parametric resonance, as occurs in the analysis of Melde's experiment on forced longitudinal vibrations of a stretched elastic string. For many kinds of carbon nanotubes (SWNT, DWNT, MWNT, ropes and strands) the resonant parameters are found to be located in an unstable region of the parameter space of Mathieu's equation. Third order wave equations are used to qualitatively describe the effects of phonon-phonon interactions and energy transfer from microwaves to CNTs. This result provides another way to input energy from microwaves to carbon nanotubes besides the usual Joule heating via electron-phonon interaction. This model appears to be the first to point out the role of nonlinear dynamics in the heating of CNTs by microwaves.
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Owens, Angela C. "An experimental study of fluid structure interaction of carbon composites under low velocity impact." Thesis, Monterey, California : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/Dec/09Dec%5FOwens.pdf.
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Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, December 2009.Thesis Advisor: Kwon, Young W. Second Reader: Didoszak, Jarema M. "December 2009." Description based on title screen as viewed on January 26, 2010. Author(s) subject terms: Composite, Carbon, Low Velocity Impact, Fluid Structure Interaction. Includes bibliographical references (p. 49-50). Also available in print.
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Bray, Shirley M. "The interaction between carbon dioxide enrichment and salinity on growth and carbon partitioning in Phaseolus vulgaris L." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0018/NQ54822.pdf.
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Arnold, Kristina. "SwapnSave - A design proposal for collectively reducing carbon emissions." Thesis, Malmö universitet, Fakulteten för kultur och samhälle (KS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-23982.
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This thesis contributes to Sustainable Interaction Design by exploring how an eco-feedback enriched design proposal may engage people to collectively reduce carbon emissions. Taking a participatory design approach, the project identified fashion consumption as an area of opportunity towards this aim and proposes a design concept as an alternative to resource and emission-intense consumption by engaging swapping and renting of fashion. Challenges found in field research with regard to re-using fashion were problematised, namely quality, trust and fairness. The project aimed to address these challenges by conceptualizing an engaging user experience that creates a community between people to share fashion with each other. Values and unique qualities of fashion were investigated as well as how visualizing the environmental impact of such activity affects user engagement. User testing suggests that such eco-feedback positively impacts engagement with the proposed concept.
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Wong, Chun-yuen. "Ruthenium-carbon bonding interaction synthesis and spectroscopic studies of ruthenium-acetylide, -carbene, -vinylidene and -allenylidene complexes." Click to view the E-thesis via HKUTO, 2004. http://sunzi.lib.hku.hk/hkuto/record/B31040858.
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Wong, Chun-yuen, and 黃駿弦. "Ruthenium-carbon bonding interaction synthesis and spectroscopic studies of ruthenium-acetylide, -carbene, -vinylidene and -allenylidene complexes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31040858.
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Salvador-Morales, Carolina. "Study of the interaction between immune system proteins and carbon nanotubes." Thesis, University of Oxford, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.437000.
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Butler, Timothy Patrick. "The interaction of light with vertically aligned arrays of carbon nanotubes." Thesis, University of Cambridge, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708152.
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Grinnell, Rachael C. "Recipes for low carbon, adaptable design." Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/25481.
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The thesis contributes a more lucid understanding of the potential for interaction amongst different facets of sustainability in the context of building design, providing evidence that the assimilation of diverse and often seemingly unconnected aspects of sustainability is not the unassuming process implicit in the current sustainability discourse. Working inductively and with a focus on two sustainable principles (the current UK government sponsored sustainability agenda, low carbon design, and an alternative interpretation, adaptable design, whose literature is framed in a sometimes complementary, at others antagonistic fashion to the former), this thesis develops an understanding of interaction in building design processes, using publically available documentary evidence and a comparative case-study approach. The thesis describes and categorises instances of interaction arising in the twenty-three case study building design processes, demonstrating both the empirical existence of interaction and improving the theoretical conceptualisation beyond basic ideas of synergy and conflict. Interaction is noted as arising from both technical incompatibilities and project actors interpretation of the agendas themselves: a socio-technical issue. The thesis distinguishes multiple approaches adopted by design teams to managing the entanglement encountered. Interpreting these interaction strategies in their case context, factors driving the selection of a particular approach are inductively derived and combined to form a tentative conceptual framework. This framework aides a systematic comparison across project cases, facilitated by the crisp set qualitative comparative analysis (csQCA) technique. Projects are described as configurations of the identified conditions and, by operationalizing interaction in a manner consistent with case study observation and the existing literatures of adaptable and low carbon design, assessed for successfulness in reconciling the agendas. The technique identifies three causal pathways to successful reconciliations of adaptable and low carbon design. Finally, the thesis makes a methodological contribution, through an evaluation of the application of QCA to a novel problem space (socio-technical, project-orientated problems of the built environment). Through the richness of documentary data obtained for study, it also demonstrates the potential effectiveness of documents as primary sources in the field of building design, where they are often relegated to a supporting role.
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Fiorin, Vittorio. "The interaction of nitric oxide with molecular adlayers adsorbed on Rh(111)." Thesis, University of Nottingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368265.
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Equey, Sébastien. "Investigation of the interaction between diamond-like carbon coatings and lubricant additives /." Zürich : ETH, 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=18049.
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Yang, Mingjun. "Simulation of mechanical properties of carbon nanotubes and their interaction with polymers." Thesis, University of Edinburgh, 2005. http://hdl.handle.net/1842/11637.
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Pavlenko, Ekaterina. "Probing interaction and dispersion of carbon nanotubes in metal and polymer matrices." Toulouse 3, 2014. http://thesesups.ups-tlse.fr/2586/.
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L'incorporation de nanotubes de carbone (NTC) dans des polymères et des métaux modifie leurs propriétés intrinsèques. Disperser des NTCs uniformément dans une matrice reste difficile du fait de leur forte agglomération. La spectroscopie Raman est une technique particulièrement adaptée pour détecter la présence et l'interaction avec l'environnement de NTCs. Dans ce travail, la spectroscopie Raman est utilisée, en association avec d'autres techniques, pour étudier les NTCs dans une matrice métallique ou polymère. Le dopage avec des super-acides, l'analyse de défauts dans les zones d'usure et la dispersion des NTCs sont abordés. L'analyse statistique des images Raman permet de générer des histogrammes permettant d'estimer la quantité et la dispersion des NTCs. La diffusion lors de recuit d'un polymère thermoplastique poly (éther-éther-cétone) ou PEEK dans des NTCs agglomérées est étudiée par imagerie Raman et microscopie électronique. Les mesures de transport électronique en fonction de la température et de la concentration de NTCs montrent une forte conductivité électrique compatible avec la formation d'un réseau percolant de NTCsThe incorporation of carbon nanotubes (CNTs) into polymers and metals modifies their intrinsic properties. Dispersing CNTs uniformly in a matrix remains challenging due to strong tube agglomeration. Raman spectroscopy is a compelling technique to detect the presence of CNTs and their interaction with the environment. In this work, Raman spectroscopy is applied in association with other techniques to investigate CNTs in a metallic or polymer matrix. Doping with superacids, analysis of defects in friction wear and CNT dispersion are investigated. Statistical analysis of Raman images are used to generate histograms of Raman bands maps in order to estimate the amount of CNTs and their dispersion. The diffusion of a Poly (Ether Ether Ketone) PEEK thermoplastic polymer into agglomerated carbon nanotubes when annealing on the surface of a polymer sheet is studied by Raman imaging and transmission electron microscopy. Electronic transport measurements as a function of temperature and CNT concentration show high electrical conductivity consistent with the formation of a uniform percolating CNT network
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Lee, Sang Joon. "Structure and Interaction Energies of Kr Atoms Adsorbed on Graphitic Amorphous Carbon." DigitalCommons@USU, 1995. https://digitalcommons.usu.edu/etd/2091.
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The physisorption of Kr on graphitic amorphous carbon (g-C) has been investigated using a statistical approach. The interaction energy calculation process (i) established a structural model of g-C and (ii) determined the adsorbate-adsorbate and the adsorbate-substrate interaction potentials on g-C.
The structural model of g-C was divided into three regions. For the interaction potential between a Kr atom and a carbon atom the short and medium range order of g-C was described with a discrete medium model based on three ring clusters using ring statistics from Beeman's continuous random network C1120 model of g-C. For the intermediate distance region, Beeman's radial distribution function was used to model g-C. A homogenous and isotropic continuous medium model was used at large distances.
The Kr-Kr and Kr-g-C interaction potentials used for Kr on g-C, which are pair-wise Lennard-Jones 6-12 potentials, are similar to Kr on graphite potentials. the validity of the model for g-C and the potentials were verified though calculations for Kr on graphite. Results compared favorably with recent literature values.
The interaction energy calculation results for Kr on a g-C substrate assert that (i) Kr adlayers will form on g-C, (ii) the structure of the Kr adlayer is governed by the substrate corrugation at low coverage and by the Kr-Kr interaction at high coverage, and (iii) there is no direct relation between the structure of Kr adlayers on g-C and those on graphite. The average binding energy of Kr on g-C is comparable with that on graphite, but the corrugation of g-C is perhaps six times that of a graphite substrate. The wrinkling of the g-C surface, due to the presence of a distribution of 5-, 6-, and 7- membered rings, is responsible for this large corrugation of the g-C substrate.
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Andrews, Michael Robert. "The interaction of deposition promoters with AGR fuel cladding surfaces." Thesis, University of Newcastle Upon Tyne, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244466.
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Andres, Jeanne Therese Hilario. "The interaction of chemical kinetics and fluid flow in the geological storage of carbon dioxide." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608059.
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Yager, Patricia L. "The microbial fate of carbon in high-latitude seas : impact of the microbial loop on oceanic uptake of CO2 /." Thesis, Connect to this title online; UW restricted, 1996. http://hdl.handle.net/1773/11001.
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Chokshi, Kunal K. "A study of inhibitor-scale interaction in carbon dioxide corrosion of mild steel." Ohio : Ohio University, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1089819131.
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Murphy, Paulette P. "The carbonate system in seawater : laboratory and field studies /." Thesis, Connect to this title online; UW restricted, 1996. http://hdl.handle.net/1773/8509.
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Bulbul, Sevtac. "Matrix Fracture Interaction In Sandstone Rocks During Carbon Dioxide, Methane And Nitrogen Injection." Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614449/index.pdf.
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The aim of the study is to investigate matrix-fracture interaction, gas oil gravity
drainage (GOGD) and diffusion mechanisms with CO2, N2 and CH4 gas injection
in a fractured system. Effects of injected gas type, initial gas saturation and
diffusion coefficient on oil recovery are studied by an experimental and
simulation work.
In the experimental study, Berea sandstone cores are placed in a core holder and
the space created around the core is considered as a surrounding fracture. System
is kept at a pressure of 250 psi by CO2, N2 and CH4 gases and at a reservoir
temperature of 70 °C. Experiments with cores having similar initial saturations resulted in the highest ndecane recovery in CO2 experiment followed by CH4 and N2. The highest solubility of CO2 in n-decane and density difference between CO2 and CO2-ndecane mixture are considered as the reason of results. CO2 injection tests with n-decane and brine saturated core with and without initial gas saturation indicate that availability of initial gas saturation in matrix increased recovery. A simulation study is continued using CMG (Computer Modeling Group Ltd.) WinProp (Microsoft Windows&trade
based Phase-Behavior and Fluid Property Program) and GEM (Generalized Equation-of-State Model Compositional Reservoir Simulator). Simulation results of CO2 experiment with initial gas show that dominant effect of GOGD decreases and diffusion becomes more effective at final production stages. Simulation study indicates an immediate, sharp decrease in oil saturation in matrix. Oil in matrix migrates into fractures and moves downward as a result of GOGD with gas injection.
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Abadir, George Bassem Botros. "Simulation studies of the mechanisms of interaction between carbon nanotubes and amino acids." Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/27903.
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In this thesis, molecular dynamics and ab initio density functional theory/nonequilibrium Green’s function simulations are used to study the interaction between carbon nanotubes and amino acids. Firstly, rules for the proper choice of the parameters used in these simulations are established. It is demonstrated how the improper choice of these parameters (particularly the basis set used in ab initio simulations) can lead to quantitatively and qualitatively erroneous conclusions regarding the bandgap of the nanotubes.
It is then shown that the major forces responsible for amino-acid adsorption on carbon nanotubes are van der Waals forces, and that hydrophobic interactions may accelerate the adsorption process, but are not necessary
for it to occur. The mechanisms of interaction between carbon nanotubes and amino acids are elucidated. It is found that geometrical deformations
do not play a major role in the sensing process, and that electrostatic interactions represent the major interaction mechanism between the tubes and amino acids. Fully metallic armchair tubes are found to be insensitive to
various amino acids, while small-radius nanotubes are shown to be inadequate for sensing in aqueous media, as their response to the motion of the atoms resulting from the immersion in water is comparable to that of analyte
adsorption. Short semi-metallic tubes are revealed to be sensitive to charged amino acids, and it is demonstrated that the conductance changes induced by the adsorption of the analyte in such tubes in a two-terminal
configuration are bias-dependent. The effects of the length of the tube and adsorption-site position on the conductance of the tube are discussed. In addition, the adsorption near metallic electrodes is shown to have a negligible effect on the conductance of the tube due to the metal-induced gap states injected from the metal electrodes into the tube. Finally, the results are
used to provide general guidelines for the design of carbon-nanotube-based biosensors, as well as to help explaining previously published experimental results.
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Göhring, HOLGER [Verfasser], and Eric Jan [Akademischer Betreuer] Mittemeijer. "Interaction of carbon and nitrogen in iron / Holger Göhring ; Betreuer: Eric Jan Mittemeijer." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2016. http://d-nb.info/1124841334/34.
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Rossi, Mariʹa Piʹa Gogot︠s︡i I︠U︡ G. "Environmental scanning electron microscopy study of the interaction of carbon nanotubes with fluids /." Philadelphia, Pa. : Drexel University, 2006. http://hdl.handle.net/1860/1225.
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Knippenberg, Michael Todd. "The interaction between hydrogen and various carbon allotropes calculated using bond-order potentials." Connect to this title online, 2006. http://etd.lib.clemson.edu/documents/1171294045/.
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Qian, Haifeng. "Variability of terrestrial carbon cycle and its interaction with climate under global warming." College Park, Md.: University of Maryland, 2008. http://hdl.handle.net/1903/8564.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2008.Thesis research directed by: Dept. of Atmospheric and Oceanic Science. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Topouzi, Marina. "Occupants' interaction with low-carbon retrofitted homes and its impact on energy use." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:ac363b69-c414-4ef8-875a-ada6a9867f8f.
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Current regulatory and other policy trends in housing refurbishment relating to low-carbon performance standards tend to involve complex technologies and systems as well as innovative solutions to achieve 80% emissions reduction in line with the UK national target for 2050. Indicators of domestic energy performance tend to assume ideal performance of materials, complex systems and services, and that they are installed to high standards and under specific conditions, as well as rational occupant behaviour and interactions. Previous studies exploring the influence of socio-technical factors on the UK's domestic energy use highlight that one of the main reasons for under-performance of individual projects is the lack of understanding of how people interact with domestic technology. Considering this, and given that there is still little evidence on deep refurbishments that implement low-carbon 'whole house' approaches in the UK, this research explored occupants' interaction with heating and ventilation measures as these were designed, installed and operated. The main concern was to identify the type of interactions that occur between occupants (social housing tenants) and building systems (mainly low-carbon heating and ventilation systems), and how that influences actual energy use. Using a sample of 26 social housing properties involved in the Retrofit for the Future competition in the UK, the study employed an socio-technical mixed methods approach, in which qualitative and quantitative empirical data were explored together, cross-checking occupants' 'doings' and 'sayings'. A combination of theories was used to analyse the complex interrelated factors involved in users' interaction with building systems. The analysis identifies key factors that affect significantly occupants' everyday practices and their interactions with the new measures: thermal comfort and pastexperiences with measures and controls; knowledge and skills (of both occupants and those involved in the project); design of the technical interventions (systems/measures) and quality of their installation. The findings from this research showed that active measures (such as intelligent and conventional heating controls, MVHR boosters, etc.) fostered direct interaction with active users when there were no design or installation faults. On the contrary, low-carbon measures that are designed and installed to be passive (such as MVHR systems operation) tend, in practice, to involve indirect interactions with active users. The research findings provide an insight into the 'in-use' factors, demonstrating to policy makers and implementers of mass refurbishment programmes the need for a framework where critical combinations of different measures and design solutions are targeted on specific house types, locations and households, in order to achieve maximum savings. Higher standards in installation of the new measures and improved quality control are also found to be a key part of refurbishment policies.
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Göhring, Holger [Verfasser], and Eric Jan [Akademischer Betreuer] Mittemeijer. "Interaction of carbon and nitrogen in iron / Holger Göhring ; Betreuer: Eric Jan Mittemeijer." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2016. http://d-nb.info/1124841334/34.
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Butzloff, Peter Robert. "Charge Interaction Effects in Epoxy with Cation Exchanged Montmorillonite Clay and Carbon Nanotubes." Thesis, University of North Texas, 2005. https://digital.library.unt.edu/ark:/67531/metadc4786/.
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The influence of charge heterogeneity in nanoparticles such as montmorillonite layered silicates (MLS) and hybrid systems of MLS + carbon nanotubes was investigated in cured and uncured epoxy. Epoxy nanocomposites made with cation-exchanged montmorillonite clay were found to form agglomerates near a critical concentration. Using differential scanning calorimetry it was determined that the mixing temperature of the epoxy + MLS mixture prior to the addition of the curing agent critically influenced the formation of the agglomerate. Cured epoxy samples showed evidence of the agglomerate being residual charge driven by maxima and minima in the concentration profiles of thermal conductivity and dielectric permittivity respectively. A hybrid nanocomposite of MLS and aniline functionalized multi walled nanotubes indicated no agglomerates. The influence of environmentally and process driven properties on the nanocomposites was investigated by examination of moisture, ultrasound, microwaves and mechanical fatigue on the properties of the hybrid systems. The results point to the importance of charge screening by adsorbed or reacted water and on nanoparticulates.
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Chokshi, Kunal. "A Study of Inhibitor-Scale Interaction in Carbon dioxide Corrosion of Mild Steel." Ohio University / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1089819131.
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Wood, Cody. "A Continuum Model for the van der Waals Interaction Energy of Carbon Nanotubes." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1493376354522434.
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Ruffe, Remi. "Etude des surfaces de carbone en interaction avec le plasma de Tore Supra." Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4799/document.
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Les tokamaks visent à réaliser la fusion contrôlée de noyaux de deutérium et de tritium par le confinement magnétique d'un plasma chaud. L'interaction entre le plasma et les parois a été étudiée en détail pour le tokamak Tore Supra. Au cours des décharges, le plasma interagit fortement avec le limiteur, formé de milliers de tuiles en composite carbone/carbone. L'érosion de ces tuiles par les flux de particules du plasma mène à la formation de co-dépôts de carbone et de deutérium qu'il est essentiel de limiter. Nous avons effectué une étude multi-échelle, principalement avec les différents outils de la microscopie électronique, sur des tuiles provenant du limiteur de Tore Supra. Une analyse des co-dépôts a permis de mettre en évidence leur topographie en forme de pointes, orientées dans une même direction quelque soit la position de la tuile sur le limiteur. L'étude de la surface de tuiles appartenant à des zones majoritairement érodées a révélé la présence d'une striation périodique de surface. Ces deux phénomènes ont été mis en relation avec la direction des flux et l'effet de la gaine faiblement magnétisée de Tore Supra a été mis en évidence. L'analyse des dépôts présents dans les interstices entre les tuiles a révélé une physique propre à ces interstices permettant la formation de dépôts en profondeur. Des nanoparticules graphitiques sphériques ont été observées, signe d'une croissance homogène locale en phase plasma. Nous avons développé des méthodes de mesure des volumes de dépôt et des volumes érodés, menant à l'établissement d'un bilan carbone et à l'évaluation de la masse de deutérium piégé, en bon accord avec les mesures in-situ réalisées dans Tore SupraTokamaks are devices aiming at achieving controlled fusion of deuterium and tritium by magnetically confining a hot plasma. The interaction between the plasma and the inner walls is a crucial issue and has been studied in detail in Tore Supra. During discharges the plasma strongly interacts with limiter, designed with thousands of carbon tiles (C/C composite). The plasma particle fluxes erode the tiles, leading to co-deposition of carbon and deuterium that should be limited. We have performed a multi-scale study of tiles extracted from the Tore Supra limiter, mainly using electron microscopy. The analysis of the co-deposits has revealed a tip-shaped topography, tips being oriented in the same direction wherever the tile over the limiter. Analyses of tiles extracted from erosion-dominated zones have revealed the presence of a periodic ripple on their surfaces. Both phenomena have been related with the direction of ion fluxes and the effect of the weakly magnetized sheath of Tore Supra has been shown. Analyses of the deposits inside the gaps in-between the tiles have revealed the existence of specific processes leading to the formation of deposits deeply inside the gaps. Graphitic nano-particles have been observed, showing the existence of local homogeneous growth processes. Finally, by measuring the deposit volume and the C/C composite eroded volume we have obtained an inventory of both carbon and deuterium which is consistent with the analyses of Tore Supra in-situ measurements
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Balatbat, Richard Vincent S. "An Investigation of Damage Arrestment Devices Application with Fastener/Hole Interaction." DigitalCommons@CalPoly, 2010. https://digitalcommons.calpoly.edu/theses/402.
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This thesis presents a parametric study on the effects of how damage arrestment devices application interacts with a fastener in a composite sandwich panel. The primary objective of the damage arrestment device was to prevent the failure of the composite face sheet, such as crack propagation, around the hole/fastener joint. The damage arrestment devices are made of composite strips that are inserted under the face sheet to increase the overall structural strength of the panel and to prevent the propagation of failure along the hole. This was supposed to be a quicker and stronger alternative to potted inserts for composite sandwich panels for designer. The manufacturing curing cycle of the composite sandwich specimens has been carried out by using a Tetrahedron Composite Air Press. The press has been used to fabricate composite sandwich panels by applying constant pressure and variable heat to create panels with dimensions of 5” x 2” x .552”. The panels were stacked using a polyurethane foam, Last-A-Foam FR-6710 with two layers of a carbon-fiber/epoxy weave, LTM45, on both sides of the foam. The specimens were loaded under a compressive strain of 0.5 mm/min. The damage arrestment devices’ thickness was varied and tested under both monotonic and fatigue loading. The experimental results indicate that as the thickness of the device increased the overall strength of the part increased at a parabolic curve with it topping at a thickness of 0.065” and a strength increase of 109%. Under fatigue loading, a control group test case and damage arrestment device configuration case was tested. The experimental results indicate that both cases have similar fatigue trends but shows that the damage arrestment specimens are stronger due to the increase of structural strength. The experimental results were compared with numerical results or Finite Element Model. The results showed that numerical results can capture the linear or elastic portion of the experimental results having identical Elastic Modulus values. The models do differ in the maximum displacement of the specimen and the failure mode around the hole of the composite sandwich panel. The discrepancy in displacement and the failure mode was attributed to inaccurate loading on the hole of the composite sandwich panel and non-linear modeling of the solution. The correlation between the FEM and the experimental data was good enough in predicting the trends of the composite sandwich panels.
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Kausar, Rehana. "Surface studies of silicon carbide deposition on carbon and tungsten substrates." Thesis, University of Salford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314000.
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Ekne, Samuel. "Teaching climate change : Creating and testing an interactive visualization of carbon emissions in order to increase awareness." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-238635.
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A gap of knowledge exists between the latest climate change research and the general public. The goal of this thesis is to bridge that gap by making the information more accessible and easier to understand. A proof-of-concept model is created with the goal to visualize carbon emission data, namely size relations between countries, source of emissions per country and the current state of carbon emissions compared to a stated goal (the Paris Agreement), and give the user options to reach said goal by manipulating percentages of renewable energy, electric vehicles, and industry, on a global or local scale.User studies are then performed with members of the target group (students age 13-15) to test whether these visualizations are intuitive and accurately communicates the visualized data. The studies are effective and the goal of the visualization is reached.Det finns en informationslucka mellan den nyaste forskningen inom klimatförändring och den allmänna befolkningen. Målet med denna tes är att minska luckan genom att göra den informationen lättare att förstå. En proof-of-concept modell skapas med målet att visualisera kolutsläppsdata, specifikt storleksförhållanden mellan olika länder, utsläppskällor för olika länder, samt det nuvarande läget av kolutsläpp jämfört med ett framtida mål (Paris Agreement), och att ge användaren alternativ för att uppnå det målet genom att manipulera procenten av förnyelsebar energi, elektriska fordon och industri, antingen globalt eller lokalt.Användarstudier utförs därefter med medlemmar av målgruppen (studenter 13-15 år gamla) för att se om visualiseringen är intuitiv och kommunicerar korrekt information om den visualiserade datan. Användarstudien är effektiv och visar att målet för visualiseringen är uppnått.
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Carroll, Ghita Levenstein. "Interaction between renewable energy markets and carbon markets: Optimal policies to meet societal goals." Connect to online resource, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3303850.
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Dippenaar, Francois. "The interaction between free cyanide and silver impregnated activated carbon in a column configuration." Thesis, Cape Technikon, 2000. http://hdl.handle.net/20.500.11838/883.
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Thesis (MTech (Chemical Engineering))--Cape Technikon, Cape Town, 2000Due to equilibrium constraints and the relatively slow kinetics of the cyanidation of gold ores, calcium or potassium cyanide is added to the leaching stage in excess to that required theoretically. This, in many situations, result in large concentrations of free cyanide present in the effluent streams from gold plants. In view of the toxicity of cyanide and the fact that cyanide is fatal in small dosages, authorities have been forced to tigl1ten up plant discharge regulations. Therefore, it is vital to remove cyanide from industrial effluent, not only to meet standard requirements, but also to recover the cyanide as a means of reducing chemical costs. The aim of this study is to recover, rather than destroy, free cyanide from effluent streams via a metal impregnated carbon-in-column configuration. The first part of the study focused on the mechanism of free cyanide recovery by metal impregnated carbon and the factors influencing the kinetics of the process in a batch reactor. The second part concentrates on the optimisation of such a process m a column configuration, and subsequently to recover the cyanide from the carbon. In the batch experiments it was found that impregnated metal carbon outperformed virgin carbon for free cyanide removal both from a kinetic and equilibrium point of view. Furthermore: the presence of other metal cyanides in solution with free cyanide has a negligible effect on the performance of the metal (silver) impregnated activated carbon to remove free cyanide. Moreover, scanning electron micrographs revealed distinct differences in appearance of metal impregnated carbons, which ultimately responds differently to the removal of free cyanide. Although the kinetics of adsorption in the column experiments was found to be slower when compared to that experienced in a batch reactor, preliminary results show that a column configuration could be suitable for a free cyanide recovery on a large scale. Furthemore, a sensitivity analysis using the kinetics of adsorption and equilibrium cyanide loading as criteria, has been conducted on the column configuration. In these studies the effects of different bed volumes, competitive adsorption with other species present, different flow rates, different column diameters and initial cyanide concentrations on the process have been evaluated. These results were plotted as break-through curves, and the mass transfer zone (MTZ) was determined. It was found that impregnation in an air atmosphere yields a product with a higher capacity than in a nitrogen atmosphere, compromising carbon through combustion. Under a nitrogen atmosphere a more robust product is formed. As can be expected, lower linear velocities and/or larger bed volumes as well as lower initial free cyanide concentrations improve the fraction of cyanide removed in a column configuration.
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Adeyemo, Adedunni D. "Interaction of Metal Oxides with Carbon Monoxide and Nitric Oxide for Gas Sensing Applications." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1332475552.
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Lu, Jiemin. "CO2 interaction with aquifer and seal on geological timescales : the Miller oilfield, UK North Sea." Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/2568.
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Carbon Capture and Storage (CCS) has been identified as a feasible technology to reduce CO2 emissions whilst permitting the continued use of fossil fuels. Injected CO2 must remain efficiently isolated from the atmosphere on a timescale of the order of 10000 years and greater. Natural CO2-rich sites can be investigated to understand the behaviour of CO2 in geological formations on such a timescale. This thesis examines the reservoir and seal on one such oilfield. Several hydrocarbon fields in the South Viking Graben of the North Sea naturally contain CO2, which is thought to have charged from depth along the western boundary fault of the graben. The Miller oil field which contains ~ 28 mol% CO2, of isotopic composition δ13C = -8.2‰. The Upper Jurassic Brae Formation reservoir sandstones and the Kimmeridge Clay Formation (KCF) seal have been exposed to the CO2 accumulation since its emplacement. Rock samples from the reservoir sandstone and bottom of the seal mudrock were examined using multiple techniques, including XRD, SEM, fluid inclusion and carbonate stable isotope analyses. The sandstones show no features directly attributable to abundant CO2 charge. SEM analyses reveal significant heterogeneities in diagenesis within the KCF. The silt/sand lithologies of the KCF have undergone a diagenetic history similar to that of the Brae Formation sandstones. In contrast, the KCF shales display a distinctly different diagenesis of dominant dissolution of quartz and feldspar with little evidence of mineral precipitation. In both the Brae Formation and the KCF, pore-filling kaolinite, illite and carbonates are relatively late diagenetic events which can be associated with CO2-induced feldspar dissolution. Mudrock X-ray diffraction mineralogical data reveal abrupt vertical mineralogical variations across the reservoir crest in the Miller Field, while such variations are absent in a low-CO2 control well in the same geological settings. This suggests that reactions induced by abundant CO2 dissolved feldspar and produced kaolinite, carbonates and quartz in the seal, while oil emplacement inhibited the reactions in the oil leg. However, petrographic evidence and comparison between different sections argue against CO2 reactions as the sole cause for such large mineralogical variations, especially for quartz. The vertical mineralogical variations to a certain extend represent original sedimentary heterogeneity. Linear variations of carbonate δ13C with depth were discovered in both shale and silt/sand lithologies of the KCF in a 12m zone immediately above the reservoir. These features are absent in the low-CO2 control well. These trends are interpreted as dissolution of original carbonates by CO2 slowly ascending from the reservoir. New carbonates precipitated from a carbon source with upwards decreasing δ13C due to mixing between three carbon sources with different C isotopes at systematically varying ratios. The isotopes in the reservoir and the bottom of the seal suggests initial CO2 charge at about 70-80 Ma. CO2 infiltration rate is estimated at about 9.8×10-7g·cm-2·y-1. Geochemical modelling was applied to reconstruct the reservoir fluid evolution by calibrating it to mineralogy, fluid chemistry, diagenesis and fluid inclusion data. The modelling suggests that CO2 migrated into the reservoir together with a saline basinal fluid derived from the underlying evaporites at ~ 70 Ma. The CO2 and basinal water charge imposed an important influence on the mineral reactions and fluid chemistry. This study suggests that the KCF has formed an excellent CO2 seal, with no substantial breach since its charge at 70-80 Ma.
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Caba, Aaron C. "Characterization of Carbon Mat Thermoplastic Composites: Flow and Mechanical Properties." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/29104.
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Carbon mat thermoplastics (CMT) consisting of 12.7 mm or 25.4 mm long, 7.2 micrometer diameter, chopped carbon fibers in a polypropylene (PP) or poly(ethylene terephthalate) (PET) thermoplastic matrix were manufactured using the wetlay technique. This produces a porous mat with the carbon fibers well dispersed and randomly oriented in a plane. CMT composites offer substantial cost and weight savings over typical steel construction in new automotive applications. In production vehicles, automotive manufacturers have already begun to use glass mat thermoplastic (GMT) materials that use glass fiber as the reinforcement and polypropylene as the matrix. GMT parts have limitations due to the maximum achievable strength and stiffness of the material. In this study the glass fibers of traditional GMT are replaced with higher strength and higher stiffness carbon fibers.
The tensile strength and modulus and the flexural strength and modulus of the CMT materials were calculated for fiber volume fractions of 10-25%. Additionally, the length of the fiber (12.7 mm or 25.4 mm) was varied and four different fiber treatments designed to improve the bond between the fiber and the matrix were tested. It was found that the fiber length had no effect on the mechanical properties of the material since these lengths are above the critical fiber length. The tensile and the flexural moduli of the CMTs were found to increase linearly with the FVF up to 25% FVF for some treatments of the fibers. For the other treatments the linearly increasing trend was valid up to 20% FVF, then stiffness either stayed constant or decreased as the FVF was increased from 20% to 25% . The strength versus FVF curves showed trends similar to those of the modulus versus FVF curves. It is shown that choosing an appropriate sizing can extend the usable FVF range of the CMT by at least 5%. Published micromechanical relations over-predicted the tensile modulus of the composite by 20-60%. An empirical fiber efficiency relation was fit to the experimental data for the tensile modulus and the tensile strength giving excellent agreement with the experimental results.
Flow tests simulating the compression molding process were conducted on the CMT to determine what factors affect the flow viscosity of the CMT. The melt viscosity of the neat PP was measured using cone and plate rheometry at temperatures between 180°C–210°C and was fit with the Carreau relation. The through thickness packing stress of the CMT mat was measured for FVFs of 8-40% and was found to follow a power law behavior based on the local bending of fibers up to a FVF of 20.9%. Above this FVF the power law exponent decreases, and this is attributed to fracture of some of the fibers. Heated platens were used to isothermally squeeze the CMT at axial strain rates of 0.02-6 s^-1. The plot of the load-displacement behavior for the 10% FVF CMT was similar in shape to that for a fluid with a yield stress. For FVFs of 15-25% the load-displacement curves showed a load spike at the beginning of the flow, then followed the curve for a fluid with a yield stress. The matrix was burned off the squeezed samples, and the remaining carbon mat was dissected and visually inspected. It was found that fiber breakage increased and fiber length decreased as the FVF of the sample was increased.Ph. D.
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Kendall, Peter K. "Numerical study of effects of fluid-structure interaction on dynamic responses of composite plates." Thesis, Monterey, California : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/Sep/09Sep%5FKendall.pdf.
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Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, September 2009.Thesis Advisor(s): Kwon, Young W. "September 2009." Description based on title screen as viewed on 6 November 2009. Author(s) subject terms: Fluid-structure interaction, composite, carbon fiber composite, dynamic response, finite element. Includes bibliographical references (p. 95-96). Also available in print.
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Guo, Huina. "Structure, processing, and properties of polyacrylpnitrile/carbon." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/22555.
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Thesis (Ph. D.)--Textile and Fiber Engineering, Georgia Institute of Technology, 2007.Committee Chair: Satish Kumar; Committee Member: Art Ragauskas; Committee Member: Johannes Leisen; Committee Member: John Muzzy; Committee Member: Samuel Graham.
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Michan, Mario. "High electron gain from single walled carbon nanotubes stimulated by interaction with an electron beam." Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/23346.
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Carbon nanotubes, hollow cylindrical structures made of carbon atoms with diameters in the order of a few nanometres, are attractive candidates for electron emission applications. A detailed characterization of the phenomenon so-called electron-stimulated field-emission from carbon nanotubes is presented in this thesis. An electron beam hitting the tip of a nanotube biased near the threshold of field-emission can stimulate the emission of a large number of electrons from the nanotube tip. The result of this interaction is that high electron gains can be obtained with very small stimulating electron beam currents. Electron gains of up to 2300 were recorded. This is important as this effect could form the basis of several vacuum nanoelectronic devices. Possible direct and indirect electron-nanotube interaction mechanisms responsible for this high gain are discussed and substantiated through simulations. The design and assembly of an ultra high vacuum apparatus for more controlled future experiments is also presented.
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Taylor, A. O. "A molecular beam study of the interaction of hydrogen and carbon monoxide with nickel surfaces." Thesis, Imperial College London, 1985. http://hdl.handle.net/10044/1/37875.
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