Dissertations / Theses on the topic 'Dynamics in TiN'
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Ivashchenko, V., S. Veprek, and V. Shevchenko. "Comparative first-principles molecular dynamics study of TiN(001)/SiN/TiN(001) and TiN(001)/SiC/TiN(001) interfaces in superhard nanocomposites." Thesis, Видавництво СумДУ, 2011. http://essuir.sumdu.edu.ua/handle/123456789/20546.
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Heterostructures TiN(001)/SiN/TiN(001) and TiN(001)/SiC/TiN(001), with one
monolayer (ML) of interfacial SiN and SiC, respectively, inserted between five monolayer
thick B1-TiN, were investigated using first-principles quantum molecular dynamics
(QMD) calculations. The temperature dependent QMD simulations at 300 K in
combination with subsequent variable-cell structural relaxation revealed that the
TiN(001)/SiN/TiN(001) interface exists as pseudomorphic B1-SiN layer only at 0 K,
and as a superposition of distorted octahedral SiN6 and tetrahedral SiN4 units aligned
along the (110) direction at a finite temperature. Thus, at 300 K, the interfacial layer is
not epitaxial. Instead it consists of aggregates of the B1-SiN-like and Si3N4-like distorted
clusters. However, in the the TiN(001)/SiC/TiN(001) heterostructures, the interfacial
layer remains epitaxial B1-SiC at 0 K as well as at 300 K, with only a small shift of
nitrogen atoms on both sides of the interface towards the silicon atoms. A comparison
with the results obtained by earlier "static" ab initio DFT calculations at 0 K shows the
great advantage of the QMD calculations that allow us to reveal structural reconstructions
caused by thermal activation.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/20546
2
Togo, Atsushi. "Point defects and lattice dynamics of tin oxides and lead oxides." 京都大学 (Kyoto University), 2006. http://hdl.handle.net/2433/136157.
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Polizzotti, Alex J. "Improving charge carrier dynamics in tin (II) sulfide through targeted defect engineering." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/118730.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2018.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 145-151).
Tin sulfide is an emerging material for photovoltaics, with the potential for highthroughput manufacturing to combat climate change by displacing fossil fuel generation. However, device efficiencies for SnS have plateaued at below 5% efficiency, making them as yet insufficient for commercial production. Low minority carrier lifetimes of <100 ps have been shown to be the root cause of this low performance, and carrier lifetimes >1 ns are predicted to enable >10%-efficient devices. In this thesis work, I employed defect modeling to identify the most recombination-active point defects: the extrinsic Fe[subscript Sn], Co[subscript Sn], and Mo[subscript Sn] and the intrinsic V[subscript S]. I grew SnS single crystals and demonstrated that by suppressing these defects during growth, I could improve minority carrier lifetime to >1 ns. I built a unique, highly customized close-spaced sublimation furnace to translate these learnings to device-relevent thin films. By designing a system for metal-free, sulfur-rich growth at high temperature, I was able to achieve >10 ns carrier lifetimes in SnS thin films. I fabricated initial devices with this high-purity material. While none of these devices exceed the record efficiencies, they are primarily limited by poor device construction and a resulting low fill factor, and further improvements are expected to unlock the full potential of this new, improved SnS material.
by J. Alex Polizzotti.
Ph. D.
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Gambino, Davide. "Titanium vacancy diffusion in TiN via non-equilibrium ab initio molecular dynamics." Thesis, Linköpings universitet, Teoretisk Fysik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-129555.
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Transition metal nitrides (TMNs) refractory ceramic materials are widely employed as wear-resistant protective coatings in industrial machining as well as diffusion barriers inhibiting migration of metal impurities from the interconnects to the semiconducting region of electronic devices. TiN is the prototype of this class of materials and the most studied among TMNs. However, also for this system, a complete picture of the migration processes occurring at the atomic scale is still lacking. In this work I investigate the stability of Ti vacancy configurations and corresponding migration rates in TiN by means of density functional theory (DFT) calculations and ab-initio molecular dynamics simulations (AIMD). DFT calculations show that Ti vacancies tend to stay isolated because of repulsive interaction which decreases as the inverse of the distance between the vacancies.The equilibrium jump rate of single Ti vacancies in TiN is extrapolated temperature as a function of temperature from the results of non-equilibrium AIMD simulations accelerated by a bias force field according to the color diffusion algorithm. For each force field and, the jump occurrence times are fitted with the two parameters Gamma distribution in order to obtain the non equilibrium jump rate with the corresponding uncertainty. Extrapolated equilibrium values show an Arrhenius-like behavior, with activation energy Ea= (3.78 ± 0.28)eV and attempt frequency A = 4.45 (x3.6±1) x 1014 s-1.
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Lucas, E. "Reinventing the rattling tin : explaining the dynamics of social networking site fundraising." Thesis, University of Salford, 2016. http://usir.salford.ac.uk/37711/.
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Recent social media fundraising success stories like the No Make-up Selfie and Ice Bucket Challenge campaigns, which raised millions of pounds for charities in just days, have been hailed as a new method of fundraising in a new, networked society. They also, at a first glance, appear to support claims by various scholars that social capital is on the rise because of the pervasiveness of online social networking sites (SNSs). However, SNS fundraising is still at its infancy and few professionals in the sector understand why and how it works, while guidance from academic research studies has hitherto been scarce. Inspired by a twin interest in the dynamics of communication on social networking sites and philanthropy, this study employs a multi-disciplinary approach in analysing how good will is accumulated and mobilised in support of a charitable cause in an SNS environment – an area that has been hugely neglected in computer-mediated communication (CMC) research. Drawing on social capital theory, and the concepts of mass interpersonal persuasion and online collective action, it generates a refined framework that aims to produce a rich and insightful analysis of a type of communication that is largely unexplored. A case study approach is used to collect both qualitative and quantitative data, in order to examine the dynamics of charitable asking in an SNS environment and provide a precise theoretical explanation of the ways in which social capital, as redefined by this thesis, is manifest in this context. By examining what works and why in SNS fundraising, this study is also designed to produce results that can help charities mobilise their online communities more effectively in fundraising, making a practical, as well as a theoretical contribution to knowledge. Finally, Reinventing the Rattling Tin lays claim to a few methodological innovations. It is the first UK study, for example, to use web content analysis to code the content of charity Facebook pages, and the first to devise and use a ‘shareability’ metric to measure the success of fundraising posts. It also uses a novel technique of recruiting participants for the online survey, treating online social networking as a methodological tool, as well as a research topic. This thesis finds that social capital does accrue to charities as institutional actors via their investment in SNS-mediated relationships with supporters. It presents evidence that charities invest in social capital by fostering trust, obligations, identification and social interaction, thus strengthening relationships with supporters; and mobilise social capital mainly by tapping into social influence dynamics and by reducing the cost of taking action. The most common outcome of this investment process is public endorsement of charities’ fundraising posts via sharing, and this outcome can be converted to economic capital using easy giving mechanisms like mobile text to donate codes. The four-stage process of investment-mobilisation-outcome realisation-conversion is proposed as a revised social capital framework for the study of SNS-mediated communication.
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Samson, Paul Anthony. "Reaction dynamics of small molecules at metal surfaces." Thesis, University of Liverpool, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366722.
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Kurbanoglu, Basak. "Dynamic Resistivity Behavior Of Tin Oxide Based Multilayer Thin Films Under Reducing Conditions." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607051/index.pdf.
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Effects of urban air pollution on health and environment have lead researchers to find economic air quality monitoring regulations. Since tin dioxide (SnO2) was demonstrated as a gas sensing device in 1962, tin oxide based thin film sensors have been widely studied due to their high sensitivity and fast response. The main advantages of using tin oxide sensors are their low cost, small size and low power consumption for mobile system applications. But, in order SnO2 based sensors to meet low concentration of gases they should be highly upgraded in sensitivity, selectivity and stability.
This study was focused on the capacity of dopants in the SnO2 layer to increase the sensitivity of the sensor in detecting carbon monoxide. 1 wt. % Pd promoted and 0.1 wt. % Na-1 % Pd promoted SnO2 multilayer thin films were produced by sol-gel technique followed by spin coating route on soda-lime glass substrates.
The EDX and SEM studies showed the surface composition and the surface structure is homogeneous throughout the films. The film thickness was
determined app. 450 nm from the SEM image of the cross-section, after coating 8 layers. The experiments conducted at several temperatures namely 150, 175 and 200oC, in oxygen free and 1% oxygen containing atmospheres showed that the responses at higher temperatures in the presence of oxygen were much sharper with respect to others. Besides, Na promoted test sensors showed larger responses with shorter response time in oxygen free atmospheres at relatively lower temperatures. The results showed that the sensor signal is not directly correlated with the carbon dioxide production in oxygen free atmospheres.
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Zody, Michael Charles. "Tin plating using liquid dynamic compaction." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/37514.
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Bunce, Christopher Edward. "Magnetisation dynamics in thin films." Thesis, University of York, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.495860.
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Rojas, Nicolás. "Dynamics of thin viscous layers." Nice, 2011. http://www.theses.fr/2011NICE4074.
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L’objectif principal de cette thèse est d’étudier les différents problèmes en mécanique des fluides et de l’élasticité impliquant une mince et visqueuse couche de fluides. L’ensemble minimal d’équations contenant les effets d’inertie dans un régime fortement directement dissipatives ont été trouvés, appelée la théorie de lubrification d’inertie (ILT). Nous étudions les structures observées dans le voisinage de l’instabilité de Faraday, dans la limite d’une couche très fine de fluide visqueux. Notre modèle tient compte quantitativement le seuil d’instabilité. La simulation directe de notre système permet de prédire les tendances observées dans les expériences. Le problème du ressaut hydraulique à symétrie axiale est également étudié en utilisant la théorie de la lubrification d’inertie. Des solutions asymptotiques sont trouvées et des paramètres libres sont déterminés. Les solutions de la surface libre ont été obtenues pour une large gamme de débits en bon accord avec les expériences. Différentes lois d’échelle ont été obtenues dans une certaine limite. Enfin, nous avons utilisé une approche viscoélastique pour comprendre le mouvement des sporanges lorsque les spores sont éjectées de la fougère dans l’atmosphère dans un mécanisme de reproductionThe main objective of this thesis is to study different problems in fluid mechanics and elasticity involving thin and viscous fluid layers. The minimal set equations containing inertial effect in a strongly dissipative regime has been derived, called the inertial lubrification theory (ILT). We study the patterns observed in the vicinity of the Faraday instability, in the limit of a very thin layer ova viscous fluid. Our model captures quantitatively the threshold of instability. The direct simulation of our system permits to predict the patterns observed in experiments. The hydraulic jump problem with axial symmetry is also studied using the inertial lubrification theory. Known asymptotical solutions are found and free parameters are determined. Solutions of the free surface were obtained for a wide range of flows in good agreement with experiments. Also different scaling laws were obtained in a particular limit. Finally, we have used a viscoelastic approach to understand the movement of the sporangia when spores are ejected from the fern to the atmosphere as a reproduction mechanism
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Locht, Inka L. M. "Theoretical methods for the electronic structure and magnetism of strongly correlated materials." Doctoral thesis, Uppsala universitet, Materialteori, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-308699.
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In this work we study the interesting physics of the rare earths, and the microscopic state after ultrafast magnetization dynamics in iron. Moreover, this work covers the development, examination and application of several methods used in solid state physics. The first and the last part are related to strongly correlated electrons. The second part is related to the field of ultrafast magnetization dynamics. In the first part we apply density functional theory plus dynamical mean field theory within the Hubbard I approximation to describe the interesting physics of the rare-earth metals. These elements are characterized by the localized nature of the 4f electrons and the itinerant character of the other valence electrons. We calculate a wide range of properties of the rare-earth metals and find a good correspondence with experimental data. We argue that this theory can be the basis of future investigations addressing rare-earth based materials in general. In the second part of this thesis we develop a model, based on statistical arguments, to predict the microscopic state after ultrafast magnetization dynamics in iron. We predict that the microscopic state after ultrafast demagnetization is qualitatively different from the state after ultrafast increase of magnetization. This prediction is supported by previously published spectra obtained in magneto-optical experiments. Our model makes it possible to compare the measured data to results that are calculated from microscopic properties. We also investigate the relation between the magnetic asymmetry and the magnetization. In the last part of this work we examine several methods of analytic continuation that are used in many-body physics to obtain physical quantities on real energies from either imaginary time or Matsubara frequency data. In particular, we improve the Padé approximant method of analytic continuation. We compare the reliability and performance of this and other methods for both one and two-particle Green's functions. We also investigate the advantages of implementing a method of analytic continuation based on stochastic sampling on a graphics processing unit (GPU).
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Cecchetto, Elio. "Molecular dynamics in thin glassy films." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2003. http://dare.uva.nl/document/69558.
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Fleischer, Siegfried B. "Ultrafast dynamics of Fullerene thin films." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/10750.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997.Includes bibliographical references (p. 134-143).
by Siegfried B. Fleischer.
Ph.D.
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Edmonstone, Barry David. "Dynamics of surfactant-laden thin liquid films." Thesis, Imperial College London, 2006. http://hdl.handle.net/10044/1/8832.
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Hurst, Jerome. "Ultrafast spin dynamics in ferromagnetic thin films." Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAE004/document.
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Dans cette thèse, on s’intéresse à l'étude théorique et à la simulation numérique de la dynamique de charges et de spins dans des nano-structures métalliques. Ces dernières années la physique des nano-structures métalliques à connu un intérêt croissant, aussi bien d'un point de vue de la physique fondamental que d'un point de vue des applications technologiques. Il est donc essentiel d'avoir des modèles théoriques nous permettant de décrire correctement ce type d'objets. Cette thèse comporte deux études distinctes. Dans un premier temps on utilise un modèle semi-classique dans l'espace des phases afin d'étudier la dynamique de charges et de spins dans des films ferromagnétiques(Nickel). On décrit dans le même modèle le magnétisme itinérant et le magnétisme localisé. On montre qu'il est possible, en excitant le système avec un laser pulsé femtoseconde dans le domaine du visible, de créer un courant de spin oscillant dans la direction normal du film sur des temps ultrarapides(femtoseconde). Dans un second temps on s’intéresse à la dynamique de charge d'électrons confinés dans des nano-particules d'Or ou bien encore par des potentiels anisotropes. On montre que de telles systèmes sont des candidats intéressant pour faire de la génération d'harmoniquesIn this thesis we focus on the theoritical description and on the numerical simulation of the charge and spin dynamics in metallic nano-structures. The physics of metallic nano-structures has stimulated a huge amount of scientific interest in the last two decades, both for fundamental research and for potential technological applications. The thesis is divided in two parts. In the first part we use a semiclassical phase-space model to study the ultrafast charge and spin dynamics in thin ferromagnetic films (Nickel). Both itinerant and localized magnetism are taken into account. It is shown that an oscillating spin current can be generated in the film via the application of a femtosecond laser pulse in the visible range. In the second part we focus on the charge dynamics of electrons confined in metallic nano-particles (Gold) or anisotropic wells. We show that such systems can be used for high harmonic generation
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Eksioglu, Muhittin Caner. "Mechanics and dynamics of thin wall machining." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/33334.
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Peripheral milling of thin walled aerospace components takes considerable amount of machining time as blank blocks are cut down to thin webs under excessive structural oscillations during the process. Unstable chatter vibrations and stable forced vibrations cause poor surface finish on the machined part. Predicting the process mechanics in advance eliminates the time consuming trial and error approach in reducing the vibrations which are within the tolerance limits of the part. This thesis presents the mathematical modeling of the peripheral milling of the thin walls with helical end mills. The cutting forces, vibrations and dimensional form errors left on the finish surface are predicted under stable but forced vibration conditions. The chatter stability diagram of the operation is predicted by using both frequency and semi-discrete time domain models.
The relative vibrations between the flexible part and slender end mill are consi-dered. The tool and the workpiece are discretized along the contact axis to include effect of varying cutting forces and structural dynamics. The differential milling forces are evaluated from the static chip loads contributed by the rigid body motion of the milling operation, and dynamic chip loads caused by the relative vibrations between the flexible tool and flexible thin part.
The different cylindrical end mill geometries with regular and non-uniform pitch and helix angles, and low speed process damping effects are included in the dynamic force model. The dynamic properties of the flexible structures are represented by expe-rimentally evaluated modal model in order to reduce the number of linear, periodic, delayed differential equations solved in frequency and time domain computations. The periodic, delayed differential equations are solved by the semi discrete time domain method to predict the amplitude of vibrations and forces. The equations of motion are simplified to constant coefficient type ordinary differential equations, and surface location errors are calculated by frequency domain solver.
Chatter stability lobes are calculated using semi discrete time domain and fre-quency domain methods. Chatter stability solvers are validated by conducting chatter tests for roughing and finishing stages of thin walled aluminum part at high cutting speeds, and low speed machining of rigid steel block.
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Adams, Daniel J. "Magnetization Dynamics in Coupled Thin Film Systems." ScholarWorks@UNO, 2019. https://scholarworks.uno.edu/td/2578.
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A study is presented detailing experimental investigations of magnetization dynamics in nanostructured systems which are coupled magnetically. This work seeks to characterize the anisotropy of such systems through experimental techniques which probe microwave resonant absorption in the materials.
A custom-built experimental setup, designed and assembled in our labs, is explained in detail. This setup allows for angular-dependent ferromagnetic resonance (FMR) measurements in the sample plane through vector network analyzer spectroscopy and is adaptable to two different types of coplanar waveguides. This technique has proven effective for characterization of multiple types of magnetic systems, including multilayered structures as detailed here, with different types of anisotropies while allowing us to draw analogies with more common characterization techniques. The angular FMR setup has been used to study coupled systems, such as those coupled through the Ruderman–Kittel–Kasuya–Yosida interaction as well as exchange-biased structures. These types of coupled systems have technological impacts and are highly applied in the components of magnetoresistive random access memory. Using this new characterization technique, properties of synthetic antiferromagnets have been revealed which had not been observed before.
In addition to these experiments, magnetic susceptibility and FMR in exchange biased systems have been investigated at temperatures as low as 2 K. This investigation used a new FMR spectrometer and was one of the first studies to use this instrument.
For the first time a new method of identifying several types of coupling which can be present in layered nanostructures is presented and supported through comparison with known techniques, thus connecting a new characterization technique for layered structures with decades-old procedures. Many results within this work are also supported theoretically with computer simulations.
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Lin, Fan-Yen [Verfasser]. "The dynamics of ultra-thin polymer films in different confinements studied by resonance enhanced dynamic light scattering / Fan-Yen Lin." Mainz : Universitätsbibliothek Mainz, 2015. http://d-nb.info/1070024368/34.
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Bales, Gary Steven. "Growth dynamics of amorphous and crystalline thin films." Diss., Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/29523.
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Ekberg, Nathanial Paul. "Two-phase flow in horizontal thin annuli." Thesis, Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/17250.
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Smith, Rashida. "Growth and dynamics of polyelectrolyte multilayer thin films." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=85649.
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Polyelectrolyte multilayer thin films adsorbed onto colloidal particles have been studied by solid-state nuclear magnetic resonance (NMR) spectroscopy in order to characterize the dynamic properties of the film components. In addition, the growth of the multilayer films was observed directly for the first time and quantification of the amount of polyelectrolyte adsorbed during each step was achieved. NMR relaxation measurements demonstrate that the polyions are more mobile when incorporated into a multilayer film than when in the bulk complex. The polycation, poly(diallyl dimethyl ammonium chloride) (PDADMAC) was found to exhibit greater mobility than the polyanion, poly(styrene-4-sulfonate) (PSS), becoming increasingly less mobile as layers were added to the multilayer assembly. Solid-state deuterium NMR further demonstrates the limited mobility of the PSS chain when incorporated into a multilayer film. No significant motion is observed on the kHz timescale under ambient conditions for PSS in a strong-strong polyelectrolyte film. However, a small mobile fraction, the result of loops and tails or chain ends is present when the multilayer films are exposed to humidity and salt solutions.The behavior of the adsorbed water within this multilayer system was found to be dependent on the nature of the terminating layer. The changes in water mobility represent changes in the environment throughout the entire film, while the observed changes in the polymer dynamics are associated only with the surface layer. Additionally the water is found to be more closely associated with the polyanion, associating with the polycation only when it is the terminating layer. The behavior of the water for films comprised of a weak-strong polyelectrolyte combination are similar to that of the strong-strong multilayer system, when films are assembled with the polyions having high charge density. An increase in polyelectrolyte mobility is observed when the polyanion is the terminating layer in the poly(allylamine hydrochloride) (PAH)/poly(styrene-4-sulfonate) system, the reverse of what is observed in the strong-strong system. These differences are due to the differences in intrinsic mobility between the polyions within the multilayer film.
Finally multilayer films of PAH/PSS were prepared on alumina membranes and both the flux and selectivity could be controlled over a wide range, simply by varying the pH of the layer assembly and pH of the filtrate solution. Membranes assembled at pH 3 and pH 9 have water flux values which are dependent on the solution pH, while membranes assembled at pH 7 have constant flux regardless of filtrate solution pH. The selectivity for PAH/PSS modified membranes for dye molecules in pH 7 solutions was found to be the greatest and was the result of a combination of electrostatic and hydrophobic interactions of the polyelectrolyte chains at this pH value.
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Zhao, Dong [Verfasser]. "Polarization dynamics in ferroelectric thin films / Dong Zhao." Mainz : Universitätsbibliothek Mainz, 2018. http://d-nb.info/1155509595/34.
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BAZZI, MARISA SCHMIDT. "BREAKUP DYNAMICS OF NON-NEWTONIAN THIN LIQUID SHEETS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2018. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=34574@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
FUNDAÇÃO DE APOIO À PESQUISA DO ESTADO DO RIO DE JANEIRO
PROGRAMA DE EXCELENCIA ACADEMICA
BOLSA NOTA 10
Filmes finos de líquidos estão presentes em uma gama de aplicações industriais, como processos de atomização e revestimento de substrato. O processo de quebra pode ser divido em duas etapas: o estágio de ruptura, e o estágio de retração. O primeiro, movido pelas forças de van der Waals, ocorre quando uma pequena perturbação cresce e provoca o aparecimento de um pequeno furo no filme. O segundo, movido por forças capilares, provoca o crescimento desse furo levando à desintegração do filme de líquido. A estabilidade de uma cortina de líquido depende das características da perturbação, da espessura do filme e das propriedades do fluido. Análises experimentais mostraram que uma cortina super fina pode ser obtida pela utilização de fluidos viscoelásticos. Os mecanismos físicos associados à esta estabilidade, contudo, não são totalmente compreendidos. Este trabalho apresenta um estudo numérico e teórico dos efeitos das propriedades viscoelásticas na estabilidade de uma cortina de fluido, englobando ambos os estágio do processo. As análises numéricas foram desenvolvidas através da expansão assintótica das variáveis do escoamento com aplicação de um esquema de integração no tempo totalmente implícito. A partir da análise teórica da dinâmica de ruptura foi possível obter um critério de estabilidade linear para perturbações planares e axissimétricas em fluidos Newtonianos e não-Newtonianos. O tempo de ruptura e a velocidade de retração do filme foram calculados numericamente como função das propriedades viscoelásticas do líquido. Resultados mostraram que as forças elásticas atuam de forma a dificultar o processo de quebra e retração. Análises da evolução da espessura mostraram que as propriedades reológicas do fluído também interferem no formato que o filme de fluido assume durante o processo de retração. Para regimes de baixa viscosidade, as forças elásticas atuaram evitando a formação de ondas capilares observadas em fluidos Newtonianos.
Thin free liquid sheets are ubiquitous in many industrial processes, such as atomization and curtain coating. Liquid sheets are susceptible to instabilities at the interface, which can grow, triggering a breakup process. This process can be divided into two different stages: the rupture stage and retraction. The first, driven by van der Waals force, occurs when a small instability grows until it pinches-off the sheet. The second, driven by capillary forces, induces the growth of the hole caused by the pinch-off, leading to the full disintegration of the liquid sheet. The stability of a liquid sheet depends on disturbance characteristics, sheet thickness, and fluid properties. Experimental analyses have shown that thinner stable liquid curtain can be obtained with viscoelastic liquids. The underlyning physical mechanisms associated with increased stability are, however, not fully understood. This work presents a theoretical and numerical analysis of the effect of viscoelasticity on the stability of a thin liquid sheet during both stages of the breakup process. We first analyze the rupture dynamics, deriving linear stability criteria for both planar and axisymmetric perturbations of Newtonian and Oldroyd-B liquids. The time evolution of planar and axisymmetric perturbations in an Oldroyd-B liquid sheet is evaluated using the asymptotic expansion of the flow variables and a fully-implicit time integration scheme. The rupture time and retraction velocity are calculated as a function of the viscoelastic properties. The results show that the liquid rheological behavior does not influence the linear stability criterion. Nevertheless, it has a strong effect on the growth rate of the disturbance and retraction velocity, increasing, thus, the breakup time. The results show that elastic forces act to hinder the rupture and retraction stages. Analysis of the temporal evolution of the thickness profile reveals that liquid rheological behavior also affects the shape of the liquid sheet. For low viscosity regime, the elastic forces damp the capillary waves that arise during the retraction of Newtonian sheets.
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Byrne, Matthew P. "Magnetic spin dynamics in iron phthalocyanine thin films." Thesis, California State University, Long Beach, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10167519.
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This thesis aims to build upon the previous work done on the magnetic relaxation of iron(II) phthalocyanine (FePc) thin films by exploring the dynamic aspects of coercive fields in order to determine whether FePc can be classified as a low-dimensional material known as a single chain magnet. In thin films, the chain length is controlled by deposition temperature and therefore systematic studies of the chain-length dependent properties can be made. Hysteresis loops of FePc thin-films with five different chain lengths ranging from approx. 30 nm to 300 nm were measured at a range of sweep speeds from 10.4 mT/s to 1.07 mT/s. Each measurement was repeated at 5 different temperatures in the interval from 2.5 K to 3.8 K, where hysteresis was observed. Significant reductions in coercivity with slower sweep speeds reveal the non-equilibrium behavior of the magnetic states. Mean-field theory based on one-dimensional chains within a Glauber-Ising model suggests a power law behavior of coercivity with sweep rate. Indeed all experimental data is consistent with that behavior. The critical exponent varies from 0.521 to 0.153 for short to long chains. Given the limited observational window, coercivity due to inter-chain coupling cannot fully be ruled out, yet a large dynamic response in the coercivity supports the notion of a single chain magnet.
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Patil, Anand. "Computational Simulation of Fluid Dynamics in Thin Films." Scholarship @ Claremont, 2001. https://scholarship.claremont.edu/hmc_theses/132.
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We investigate the formation of droplets in a thin liquid film on a solid substrate due to the combined action of surface tension and van der Waals forces. Current models for droplet formation assume that droplets have a shallow profile. By removing that assumption and numerically solving for stable droplet profiles, we have modelled droplets that separate from the substrate on which they sit.
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Zhang, Qiang. "Ultrafast spin dynamics in half-metallic ferromagnetic thin film /." View online version; access limited to Brown University users, 2005. http://wwwlib.umi.com/dissertations/fullcit/3174709.
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Moore, Thomas Arthur. "Dynamic hysteresis in thin magnetic films." Thesis, University of Cambridge, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.620716.
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Cuadra-Solís, Pedro-de-Jesús. "Vortex Dynamics in Superconducting Thin Films under Microwave Fields." Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/348552.
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In this thesis we have studied the vortex dynamics in type-2 superconducting thin films made of La1.82Sr0.18CuO4, patterned Pb and MgB2, by means of the combination of microwave, dc and ac measurements. In particular, we explore first the magnetic moment response in real time under continuous and pulsed microwave mode, and second commensurability effects both in presence of microwave fields under ac susceptibility mode and using microwave reflection spectrometry.
To carry out these measurements, we have designed and developed a low-temperature microwave setup to be used inside of an rf-SQUID-based magnetometer. This layout has been used to perform measurements under different microwave modes, namely sweeping, pulsed and power reflected. A theoretical model has been proposed to obtain an estimation of the characteristic frequencies and the electric and magnetic fields of the resonant structure formed by a multi-turn coil with a sample loaded in its core.
We presents the results on vortex dynamics of superconducting thin films made of La1.82Sr0.18CuO4, patterned Pb and MgB2 under continuous and pulsed microwave modes. In the first set of experiments, the temporal- and frequency-dependent magnetic moment has been investigated at different values of the temperature, dc magnetic fields, and nominal microwave power in the three samples. Irregularities forming ripples, small steps, jumps and negative peaks at discrete frequency values under different thermodynamics variables (temperature and dc magnetic field) and microwave nominal powers have registered. The presence of these frequency-triggered anomalies has been interpreted as nucleation of instabilities in the propagation of the flux front and explained by considering the energy fed at some specific resonant modes, the vortex dynamics in thin-film geometry, and the contribution from the microwave electric and magnetic fields generated in the coil. In the second set of experiments, the temporal evolution of the sample magnetization has been recorded when single microwave pulses are applied at fixed values of temperature, dc magnetic fields, pulse duration and nominal power in the La1.82Sr0.18CuO4, and MgB2 samples. The onset of a significant variation in the sample magnetization which exists below threshold values of temperature, dc magnetic field, and pulse duration is interpreted as an avalanche-like flux penetration. The microwave fields are suggested to contribute to the nucleation of the fast vortex diffusion. The additional microwave electric field is surmised to guarantees the occurrence vortex instabilities under adiabatic conditions via the enhancement of the flux flow resistivity.
We expose results obtained for patterned Pb under ac susceptibility and microwave power reflection techniques. The in-phase and out-of-phase components of the ac susceptibility are measured under the combination of crossed dc and microwave magnetic fields at different fixed values of microwave power and frequency for temperature close to Tc. The results show that commensurability effects are strongly dependent on the values of the frequency and nominal power of the microwave radiation. The magnetic field dependence of the microwave backward reflection coefficient is studied in a wide range of temperature (from 6.80 K to 7.20 K) at different fixed microwave resonant modes and powers. Commensurability effects related to the matching of the vortex lattice parameter and the antidot array spacing at integer and fractional matching field values have been observed as peaks in the magnetic field dependence of the microwave backward reflection coefficient for different values of temperature, frequency and power. These peaks appear as a result of the contribution of the vortex dynamics to the reflected signal a the matching fields and their observation depends on the values of the microwave power supplied to the sample.L’objectiu d’aquesta tesi és estudiar la dinàmica de vòrtexs en diverses capes primes superconductores de tipus-2. En particular, explorem la resposta del moment magnètic en temps real a camps continus i polsats de microones. A més, estudiem els efectes de commensurabilitat mitjançant mesures de susceptibilitat magnètica en presència de camps de microones, i fent servir també espectrometria de reflexió de microones. Les mostres utilitzades en aquesta tesis són mostres de capes primes superconductores fetes de LaSrCuO, Pb amb una formació periòdica micro-forats o antidots i MgB2. Les mesures dels moments magnètics, de la magnetització en funció del temps i de la susceptibilitat magnètica es van realitzar amb un magnetòmetre MPMS basat en un dispositiu rf-SQUID. Per realitzar mesures de microones a baixes temperatures, es va dissenyar una sonda formada per un cable coaxial semi-rígid el qual acaba en una bobina de múltiples voltes amb la mostra localitzada al seu nucli (CS). Per caracteritzar l’estructura ressonant formada pel CS, s’ha proposat un model teòric basat en el ressonador helicoïdal. L’estudi de la dinàmica de vòrtexs sota l’escombrat de freqüència es va dur a terme en les tres mostres esmentades anteriorment. La relaxació monòtona és interrompuda per la presència d’irregularitats en forma de salts, pics negatius, ondulacions i petits passos. Aquestes anomalies apareixen a cert valors de la freqüència de microones i a diferents valors de les variables termodinàmiques (temperatura i camp magnètic continu) i dels paràmetres d’excitació de microones (potència i freqüència). La presència d’irregularitats en la resposta del moment magnètic en funció de la freqüència apareix determinada per la freqüència ressonant del CS. Altres aspectes que poden afavorir l’aparició d’aquestes irregularitats són la geometria de la capa fina i la contribució dels camps elèctrics i magnètics de microones. Aquests últims resulten significatius a la vora de la regió mostra-bobina i poden ajudar a activar inestabilitats termo-electromagnètiques dels vòrtexs. Particularment, la contribució del camp elèctric pot facilitar el desenvolupament d’aquesta mena d’inestabilitat en condicions adiabàtiques. El registre de la variació temporal de la magnetització sota la influència d’un pols de microones es va dur a terme en las mostres LaSrCuO i MgB2. Les corbes d’evolució temporal de la variació de la magnetització mostren clarament un règim de ràpida difusió dels vòrtexs. Aquest règims existeixen dins d’un marge de valors del camp magnètic continu, la temperatura, i la durada del pols. A més, aquestes corbes presenten valors de màxima difusió en funció d’aquests mateixos paràmetres. La presència d’aquestes inestabilitats disparades pels pols sembla que resulten de la contribució dels camps elèctrics i magnètics de microones i de la geometria de capa prima. Les mesures dels components de la susceptibilitat magnètica en funció del camp magnètic continu irradiat amb diferents valors de potència i freqüència de microones mostren els característics efectes de commensurabilitat per a múltiples enters i fraccionaris dels camps de coincidència (matching). Les corbes a diferents valors de freqüència i potència mostra que l’augment de qualsevol d’aquest dos paràmetres resulta en la reducció de l’apantallament i l’increment de la dissipació. Aquest efecte va ser confirmat realitzant mesures de les components de la susceptibilitat magnètica en funció de la potència als diferents valors de la freqüència de microones. Les corbes del mòdul del coeficient de reflexió de microones en funció del camp magnètic continu a una potència i freqüència de microones fixes, mesurades a diferents valors de temperatura, mostren clarament els efectes de commensurabilitat. L’empremta d’aquest efecte es mostra en forma de pics a valors enters i fraccionaris dels camps de coincidència. L’observació dels pics a les corbes del coeficient de reflexió apareix com a resultat de la contribució de la dinàmica de vòrtexs al senyal reflectit als camps de coincidència. La presència d’aquest pics es pot explicar considerant els conceptes de la conductivitat complexa del model de dos fluids, la longitud de penetració de London i les forces que descriuen la dinàmica de vòrtexs en l’equació de balanç fenomenològic. Les limitacions tèrmiques de la sonda experimental han estat testades fent mesures del coeficient de reflexió en funció del camp magnètic continu a diferents valors de la potència de microones, per a valors fixos de temperatura.
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Alavi, Ali. "Molecular-dynamics studies of thin films and charge-transfer." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358367.
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Wu, Han. "Dislocation Dynamics Simulations of Plasticity in Cu Thin Films." Thesis, University of North Texas, 2013. https://digital.library.unt.edu/ark:/67531/metadc500046/.
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Strong size effects in plastic deformation of thin films have been experimentally observed, indicating non-traditional deformation mechanisms. These observations require improved understanding of the behavior of dislocation in small size materials, as they are the primary plastic deformation carrier. Dislocation dynamics (DD) is a computational method that is capable of directly simulating the motion and interaction of dislocations in crystalline materials. This provides a convenient approach to study micro plasticity in thin films. While two-dimensional dislocation dynamics simulation in thin film proved that the size effect fits Hall-Petch equation very well, there are issues related to three-dimensional size effects. In this work, three-dimensional dislocation dynamics simulations are used to study model cooper thin film deformation. Grain boundary is modeled as impenetrable obstacle to dislocation motion in this work. Both tension and cyclic loadings are applied and a wide range of size and geometry of thin films are studied. The results not only compare well with experimentally observed size effects on thin film strength, but also provide many details on dislocation processes in thin films, which could greatly help formulate new mechanisms of dislocation-based plasticity.
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Inoue, Rintaro. "Dynamics in Polymer Thin Films by Inelastic Neutron Scattering." 京都大学 (Kyoto University), 2008. http://hdl.handle.net/2433/57278.
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Slade, David Ronald James. "Gravity-driven thin liquid films : rivulets and flow dynamics." Thesis, University of Leeds, 2013. http://etheses.whiterose.ac.uk/5826/.
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The work presented in this thesis focuses on the classical problem of gravity-driven thin films flowing over rigid substrate. Two problems are considered, the formation of rivulets at the advancing front of a spreading liquid and the inner flow structures formed when a continuous fluid film flows over a substrate on whose surface topographical features are present. The governing equations for each problem are thus formulated in two distinct forms: one using the long-wave approximation theory and the other the full Navier-Stokes and continuity equations. Accordingly, two state-of-the-art computational methodologies are developed and utilised to extract tractable numerical solutions from the two equation sets. The first problem of rivulet formation, explored using an error-controlled adaptive multigrid method to solve the lubrication equations, builds on the seminal work of Huppert (1982). By constructing a systematic and thorough data set for both fully and partially wetting liquids, a new expression for the wavelength of the rivulet pattern is obtained incorporating the wetting properties of the film. Long-time solutions uncover the transient dynamics that are associated with rivulet formation such as the merging of neighbouring fingers. The study is extended to consider film flow on the outer and inner surfaces of a cylinder; curvature effects becoming prevalent as the radius of the cylinder decreases. The cylinder’s circumference counter-acts curvature effects in that at a critical value, the evolution of the contact line is restricted to a single rivulet. The impact of surface heterogeneities (topographic and chemical), as well as the presence of surface tension gradients, on rivulet evolution is also explored. Distinctly different in focus, the induction of the transport of liquid from separated re-circulating regions in the valleys of substrate topography is investigated. Results from this preliminary work demonstrate how pulsed surface waves passing over the topography to break the symmetry and excite the separatrix, forming lobes which transport liquid across the boundary between the bulk and eddy flow. Using particle tracking calculations to visualise this phenomena reveals the dependence of the transport enhancement on the size of the free-surface disturbance created.
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Richter, Kornel. "Study of the fast domain wall dynamics in thin magnetic wires." Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-01004612.
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The domain wall dynamics is used in many spintronic devices based on the uniaxial ferromagnetic wires to transport and store information. Therefore, the domain wall velocity is one of the main parameters that determine the operation speed of these devices. Recently, a big attention is being paid to amorphous glass-coated microwires due to the very high domain wall velocities that reach up to 20 km/s. In this work, the fast domain wall propagation in amorphous glass-coated microwires was found in the presence of two main factors: (i) relatively low magnetic anisotropy, (ii) complex geometry of magnetic anisotropies given by internal distribution of mechanical stresses. The domain wall dynamics was examined in amorphous glass-coated microwires of reduced diameter down to 1 μm. It was shown, that the domain wall dynamics in these wires is the same as in wires of bigger diameter. It proves that the high domain wall velocities in microwires are not the effect of microwire diameter value. The direct observation of the surface domain wall structure by use of MOKE microscope confirmed that the domain wall is inclined relatively to the main axis. A new method for magneto-optical observation of the samples with cylindrical geometry was proposed. The inclined structure of the domain wall was found to be partially responsible for the high apparent domain wall velocity measured by the Sixtus-Tonks method in microwires.
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Kumar, Shreyas. "Simulations of Surfactant Driven Thin Film Flow." Scholarship @ Claremont, 2013. http://scholarship.claremont.edu/hmc_theses/63.
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This thesis is intended to fulfill the requirements of the Math and Physics departments at Harvey Mudd College. We begin with a brief introduction to the study of surfactant dynamics followed by some background on the experimental framework our work is related to. We then go through a derivation of the model we use, and explore in depth the nature of the Equation of State (EoS), the relationship between the surface tension on a fluid and the surfactant concentration. We consider the effect of using an empirical equation of state on the results of the simulations and compare the new results against the results produced using a multilayer (EoS) as well as experimental observations. We find that the empirical EoS leads to two new behaviors - preserving of large gradients of surfactant concentration and the occurrence of dynamics in distinct regimes. These behaviors suggest that the empirical EoS improves the agreement of the model’s prediction with experiment.
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Spitzner, Matthew James. "Response of tin whiskers to dynamic input mathematical modeling and experimental property measurement /." [Ames, Iowa : Iowa State University], 2009. 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:1464391.
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Shim, V. P. W. "Dynamic crushing of thin-walled tube arrays." Thesis, University of Cambridge, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372916.
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Tian, Tian [Verfasser]. "Spring bloom dynamics in a coastal marine ecosystem : identification of key processes / Tian Tian." Kiel : Universitätsbibliothek Kiel, 2011. http://d-nb.info/1020166770/34.
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Xu, Kewei. "Single Molecule Studies of Diffusion Dynamics in Polymer Thin Films Near Tg." Thesis, Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/16233.
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For polymers near the glass transition, the dynamics in some regions can be orders of magnitude different compared with the dynamics in other regions only a few nanometers away, so called spatial heterogeneity [1]. In this thesis, single molecule fluorescence microscopy as a powerful tool, was applied to study the spatially heterogeneous dynamics, both orientational and translational, within the polymer matrix near the glass transition temperature. With our total internal reflection fluorescence microscopy (TIRFM) methods, many individual fluorescent dye molecules embedded in the poly (isopropyl acrylate) (PIPA) thin films can be simultaneously excited. Their emission patterns are analyzed using our orientation determination methods [2] to give the true 3D orientational trajectories of the individual molecules. At Tg < T < 1.2 Tg, single molecule tracking was used to study the dye molecules translational diffusion. Results show that, below 1.1 Tg, the probe molecules are in the confined flow region [3]; at T > 1.1 Tg, the diffusion follows normal diffusion model; at T = 1.2 Tg, although the statistical results shows that normal random walk behavior is followed, the individual molecules still show different diffusion behaviors, clear evidence of the spatial heterogeneity that still exists at this temperature.
The second part of this thesis is a development of the 3-detector method to determine the 3D orientation of single molecules [4]. This method is based on the work proposed by Fourkas [4] in 2001. Results utilizing this experimental setup are compared with our emission pattern fitting methods. The results show that, with a little bit higher error range (10º in θ, 20º in φ), the 3-detector method can give agreeable orientation fittings, further more, with higher time resolution of < 10 ms. This 3-detector method is useful and can be applied to study the fast orientation dynamics in different systems.
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Findlay, James. "A study of the vibrational characteristics of thin composite plates with manufacturing imperfections." Thesis, University of the West of Scotland, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266696.
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Strothkämper, Christian [Verfasser]. "Charge Carrier Dynamics in Thin Film Solar Cells / Christian Strothkämper." Berlin : Freie Universität Berlin, 2013. http://d-nb.info/1037725832/34.
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Saprykin, Sergey. "Nonlinear wave transitions and complex spatiotemporal dynamics in thin films." Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.440444.
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Zou, Xiao. "Fast magnetisation dynamics in magnetite and RE-TM thin films." Thesis, University of York, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.534933.
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Chang, Wendi. "Modification of exciton energies and dynamics for thin film optoelectronics." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/109011.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2017.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 157-171).
Organic and nano-crystal thin film semiconductors have proven to be effective materials for a range of optoelectronic applications including light emitting diodes, visible wavelength lasers, photovoltaics, and sensors. Mediating photons and charges, excitons are responsible for electrical and optical properties in these energetically disordered media. To improve current technology and develop novel applications, a thorough understanding of exciton dynamics is crucial. This thesis focuses on modifying exciton dynamics in organic and nanocrystal thin films with spectroscopic monitoring for optoelectronic applications. First, we study local dielectric effects in doped organic thin films, which depends on material deposition and molecular density. An external pressure technique is used to modify molecular density, tuning exciton energies and dynamics as explained by solvation theory and exciton energy transfer. We extend this molecular density tuning method, coupled with other measurements, including optical imaging, magnetic field effect, and electric field effect to modify and monitor charge transfer (CT) exciton energy and dynamics. As intermediaries between excitons and free charges in organic photovoltaic donor-acceptor material systems, CT exciton state dynamics is still a subject of much debate. The effect of CT spin states on photocurrent generation is explored, revealing guidelines for material selection and molecule engineering with potential benefits in optimizing molecular density. Further investigation of low-energy CT exciton transport leads to evidence of spatial motion between interfacial states, driven by local energy disorder. These techniques and results directly apply to optimizing OPV devices, but may also be extended to other applications. This thesis also includes an investigate of ultrafast electric field effect on organic and colloidal quantum dot thin films, largely unexplored in previous works. We observe exciton luminescence and non-perturbative energy tuning of exciton states under terahertz electromagnetic radiation, developing a potential platform for detectors and cameras for coherent terahertz sensing. Lastly, we discuss a new fabrication technique to integrate organic thin films into micro-electro-mechanical system microcavity device designs. The demonstrated electrically tunable microcavity structures not only applicable as wavelength-tunable lasers and pressure sensors, but also presents a good example of fabrication flexibility and challenges of employing organic and nano-crystal thin films.
by Wendi Chang.
Ph. D.
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Lappe, Tim [Verfasser]. "Non-Markovian Dynamics of Open Bose-Einstein Condensates / Tim Lappe." Bonn : Universitäts- und Landesbibliothek Bonn, 2021. http://d-nb.info/1230878653/34.
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Madaras, Scott. "Insulator To Metal Transition Dynamics Of Vanadium Dioxide Thin Films." W&M ScholarWorks, 2020. https://scholarworks.wm.edu/etd/1616444322.
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Vanadium Dioxide (VO2) is a strongly correlated material which has been studied for many decades. VO2 has been proposed for uses in technologies such as optical modulators, IR modulators, optical switches and Mott memory devices. These technologies are taking advantage of VO2’s insulator to metal transition (IMT) and the corresponding changes to the optical and material properties. The insulator to metal transition in VO2 can be accessed by thermal heating, applied electric field, or ultra-fast photo induced processes. Recently, thin films of VO2 grown on Titanium Dioxide doped with Niobium (TiO2:Nb), have shown promise as a possible UV photo detector with high quantum efficiency which utilizes a heterostructure between these two materials. In this work, the dynamics of the IMT on thin films of VO2 is explored. We show that surface plasmons generated in an Au thin film can induce the insulator to metal transition in a thin film of VO2 due to the enhanced electric field as well as help detect the IMT via changes in its resonance condition. Time resolved pump probe studies were also done on thin films of VO2 grown on TiO2 and TiO2:Nb, using UV photon energy of 3.1 eV (400nm wavelength). The fluence threshold of the IMT at 3.1 eV was significantly lower than published values for the 1.55 eV pump fluence. The time response of the IMT shows uncommon reflectivity dynamics in these samples. The response was partially attributed to internal interference of the reflected probe beam from the inhomogeneous layers formed inside the film by different phases of VO2, and can be elucidated by a diffusion model with respect to its optical properties. Finally, the photocurrent generation time constants for the sample with highest quantum efficiency are given and compared to its ultrafast photo induced IMT time constants.
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Sandler, Gene Michael. "Computational analyses of magnetization dynamics in thin film write heads /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC IP addresses, 1998. http://wwwlib.umi.com/cr/ucsd/fullcit?p9906468.
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Hu, Yanhong. "Molecular dynamics studies of thin film nucleation and substrate modification." [Gainesville, Fla.] : University of Florida, 2003. http://purl.fcla.edu/fcla/etd/UFE0000955.
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Joseph, P. V. "The compressive behaviour of thin-walled cold-formed steel columns." Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382225.
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Oguz, Cihan. "Control-oriented modeling of discrete configuration molecular scale processes applications in polymer synthesis and thin film growth /." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/19867.
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Thesis (Ph.D)--Chemical Engineering, Georgia Institute of Technology, 2008.Committee Chair: Gallivan, Martha A.; Committee Member: Hess, Dennis; Committee Member: Lee, Jay H.; Committee Member: Li, Mo; Committee Member: Ludovice, Pete.
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Choi, Jou-Young. "Flexible multibody analysis of thin structures with actuated components." Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/12532.
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