The present thesis is examining the forced vibrations of a circular cylinder in the low Reynolds number flow of 200. A numerical study is performed that employs an already existing algorithm developed by (Breuer 1998) and enhanced with the characteristic of the cylinder's motion by (MadaniKermani 2014) who employed the moving frame of reference method of (L. Li, Sherwin et al. 2002). The algorithm was extensively assessed for the benchmark studies of flow around a stationary circular cylinder. A new observation was made on the effect of the aspect ratio of the computational cells in the mid region of the wake. The studies so far are emphasizing on the characteristic of a dense mesh, with a small aspect ratio, in the high divergence areas in the near region of the cylinder surface, neglecting the effect of the regions away from the surface. The present study on a stationary circular cylinder flow, proved that the aspect ratio of the distant cells has a significant effect on the St number and the force coefficients. The main study of the thesis emphasizes on the lock-in region where the wake oscillates in unison with the harmonic motion of the cylinder. The study makes a new observation on the qualitative and quantitative description of the lock-in conditions. In particular, it reveals two regions of resonance and non-resonance lock-in. Despite the fact that the lock-in is achieved, when the frequency ratio is in the first part of the region away from the unity ratio, the forces are not greatly magnified. As the ratio approaches the unity the forces experience a resonance that reaches the highest value after the unity. Furthermore, the adaptation time of the flow to the motion of the cylinder is examined and extends the results of (Anagnostopoulos 2000) to the full extent of the lock-in and the non-lock-in regions. More precisely the flow strives to reach a steady state when it is in the lock-in region rather in the non-lock in cases it reaches the steady state faster. It is postulated that the adaptation time depends on both the numerical and the physical adaptation. Moreover, the force coefficients characteristic of sinusoidal behaviour in the lock-in region is attempted to be approximated by a Newton polynomial that is built by making use of the divided differences method. The amplitude of the forces is approximated by a third degree Netwon polynomial built from the results of the present thesis simulations. The use of an approximation is providing faster results ignoring the need for a full resolution of the Navier-Stokes equation.

The physical properties and the stability of alcohol containing emulsions made with sodium caseinate using two types of oil, canola oil and coconut oil, were investigated. The region of emulsion stability was presented on ternary phase diagrams. Emulsion stability was limited to emulsion compositions in the range of sodium caseinate solutions between 32-68 %wt, oil contents between 10-53 %wt and ethanol concentrations from 8 to 32 %wt. The type of oil had a minor effect on emulsion stability, but stability was sensitive to ethanol content and casein/oil ratio. Emulsions were classified as Newtonian fluids, with high ethanol content (> 20 %wt) being low viscosity and those of low ethanol content (< 20 %wt) being of high viscosity. Analysis of emulsion droplet sizes showed that the presence of ethanol affected the average droplet size. From lipid oxidation determinations, there was no clear correlation between casein/oil ratio and concentration of lipid hydroperoxides

The physical properties and the stability of alcohol containing emulsions made with sodium caseinate using two types of oil, canola oil and coconut oil, were investigated. The region of emulsion stability was presented on ternary phase diagrams. Emulsion stability was limited to emulsion compositions in the range of sodium caseinate solutions between 32-68 %wt, oil contents between 10-53 %wt and ethanol concentrations from 8 to 32 %wt. The type of oil had a minor effect on emulsion stability, but stability was sensitive to ethanol content and casein/oil ratio. Emulsions were classified as Newtonian fluids, with high ethanol content (> 20 %wt) being low viscosity and those of low ethanol content (< 20 %wt) being of high viscosity. Analysis of emulsion droplet sizes showed that the presence of ethanol affected the average droplet size. From lipid oxidation determinations, there was no clear correlation between casein/oil ratio and concentration of lipid hydroperoxides

Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 101-103). Also available via the Internet.

Previously published work on the development of the Pt-based superalloys for high temperature and special applications, as well as phase equilibria work, showed that there were problems and uncertainties with the available Pt-Al phase diagram. The aim of the current work was to make a comprehensive study of all relevant phases, and to clarify the phase boundaries of the phases: (Pt), Pt3Al (all temperature versions), Pt2Al (both phases), and Pt5Al3, by use of higher resolution SEM and XRD. A displacive transformation was confirmed for cubic Pt3Al to tetragonal Pt3Al and from high temperature Pt2Al to low temperature Pt2Al. The -phase was observed to be present, the phase reactions were confirmed and the eutectic composition was found. The Pt6Al21 phase was identified instead of Pt5Al21, and was deduced to be a different interpretation of the same phase, although the former had been described as a metastable phase. The phases and phase boundaries were found to generally agree with Massalski, and disagreed with Oya et al. ’s phase diagram

Investigações dos sistemas binários LiF-BiF3 e NaF-BiF3 foram realizadas com o objetivo de esclarecer o comportamento térmico e os equilíbrios de fase destes sistemas e das suas fases intermediárias, um requisito importante para a obtenção de cristais de alta qualidade. Amostras de toda a faixa de composições (0 a 100 mol% BiF3) de ambos os sistemas foram analisadas em ensaios de análise térmica diferencial (DTA) e termogravimetria (TG), e também de calorimetria exploratória diferencial (DSC). Algumas composições específicas foram selecionadas para difração de raios-X para complementação dos dados experimentais. Devido à grande vulnerabilidade do BiF3 à contaminação por oxigênio, sua volatilidade e propensão a danificar peças de metal quando aquecido, foi necessário determinar as condições ótimas para os ensaios de análise térmica antes de investigar os sistemas em si. As relações de fase no sistema LiF-BiF3 foram completamente elucidadas e um diagrama de fases foi proposto e avaliado teoricamente mediante o software comercial Factsage. O diagrama em si consiste em um sistema peritético simples, no qual o único composto interno, o LiBiF4 se decompõe em LiF mais uma fase líquida. O sistema NaF-BiF3 não pôde ser completamente elucidado, sendo que as relações de fase do lado pobre em NaF (> 50% BiF3) ainda não são conhecidas. No lado rico em NaF, entretanto, identificou-se a possível decomposição peritectóide do composto NaBiF4. Em ambos os sistemas, foram observadas estruturas cristalográficas discrepantes daquelas da literatura para os compostos mistos, LiBiF4 , NaBiF4 e uma solução sólida de NaF e BiF3 chamada de fase I. As estruturas observadas experimentalmente permanecem desconhecidas e explicações para as discrepâncias foram propostas. / Investigations of the binary systems LiF-BiF3 and NaF-BiF3 were performed with the objective of clarifying the thermal behavior and phase equilibria of these systems and their intermediary phases, an important requisite for high-quality crystal growth. Several samples in the entire range of compositions (0 to 100 mol% BiF3) of both systems were subjected to experiments of differential thermal analysis (DTA) and thermogravimetry (TG), and also of differential scanning calorimetry (DSC). A few specific compositions were selected for X-ray diffraction to supplement the experimental data. Due to the high vulnerability of BiF3 to oxygen contamination, its volatility and propensity to destroy metal parts upon heating, it was necessary to determine the optimal conditions for thermal analysis before investigating the systems themselves. Phase relations in the system LiF-BiF3 were completely clarified and a phase diagram was calculated and evaluated via the commercial software Factsage. The diagram itself consists in a simple peritectic system in which the only intermediary compound, LiBiF4, decomposes into LiF and a liquid phase. The NaF-BiF3 system could not be completely elucidated and the phase relations in the NaF poor side (> 50% BiF3) are still unknown. In the NaF rich side, however, the possible peritectoid decomposition of the compound NaBiF4 was identified. In both systems X-ray diffraction yielded crystal structures discrepant with the literature for the intermediary phases, LiBiF4, NaBiF4 and a solid solution of NaF and BiF3 called I. The observed structures remain unknown and explanations for the discrepancies were proposed.

本論文包括對 Jaynes-Cummings-Hubbard (JCH) 系統的研究。在這個系統中，每個耦合光學腔之內都放置了一顆雙態原子，偶極相互作用導致系統有激發光子和原子的自由度。對量子電動力學系統的研究，使我們對光子與原子間的相互作用以及量子相變有更深的認識。 / 我們研究了一維JCH系統中有兩個激發子的本徵態。我們發現當真空拉比頻率與腔間穿隧率之比超過某一臨界值，兩個激發子的束縛態就會出現。 / 我們還為兩個腔的JCH系統之演化作出研究，並指出系統的量子態在一定條件下可演變成薛丁格貓態。從相干態演化到薛丁格貓態所需的時間亦被估計。 / 最後，我們使用主方程來探討驅動JCH系統的去相干。在這篇論文中，我們提出了一些低激發量的穩態的例子。許多不同的穩態系統的光子統計將被討論。 / This thesis comprises of an investigation of the Jaynes-Cummings-Hubbard (JCH) system. In such a system, single two-level atoms are embedded in each coupled optical cavity, and the dipole interaction leads to dynamics involving photonic and atomic degrees of freedom. The investigation of quantum electrodynamics in the system provides insight about the behaviour of strongly interacting photons and atoms and quantum phase transition. / We examine the eigenstates of the one-dimensional JCH system in the two-excitation subspace. We discover that two-excitation bound states emerge when the ratio of vacuum Rabi frequency to the tunnelling rate between cavities exceeds a critical value. / We also study for the time evolution of a two-cavity JCH system, and indicate that the evolved state can be a Schrödinger's cat state under certain conditions. The time required for evolving a coherent state into a Schrödinger's cat state is also estimated. / Finally, we investigate the decoherence of a driven JCH system by using the master equation. In this thesis we present several examples of steady state when the total number of excitation is low. The photon statistics of the steady state of the system will be discussed. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Wong, Tsz Ching Max = Jaynes-Cummings-Hubbard模型的課題 / 黃子澄. / "November 2012." / Thesis (M.Phil.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 79-84). / Abstracts also in Chinese. / Wong, Tsz Ching Max = Jaynes-Cummings-Hubbard mo xing de ke ti / Huang Zicheng. / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Basic Description of the Jaynes-Cummings-Hubbard Model --- p.4 / Chapter 2.1 --- Jaynes-Cummings Model --- p.4 / Chapter 2.1.1 --- Hamiltonian --- p.5 / Chapter 2.1.2 --- Energy Eigenstates --- p.6 / Chapter 2.2 --- Coupled-cavity System without Atoms --- p.8 / Chapter 2.2.1 --- A One-dimensional Coupled-cavity Chain --- p.8 / Chapter 2.2.2 --- Normal Modes --- p.9 / Chapter 2.3 --- Jaynes-Cummings-Hubbard Model --- p.10 / Chapter 2.3.1 --- Eigenstates of Single Excitation --- p.11 / Chapter 2.3.2 --- Dynamics of Single Excitation --- p.12 / Chapter 2.3.3 --- Single Excitation in the Weak Coupling Limit --- p.15 / Chapter 2.3.4 --- Single Excitation in the Strong Coupling Limit --- p.16 / Chapter 3 --- Solution of the JCH Model with Two Excitations --- p.17 / Chapter 3.1 --- Two-particle Bound States in the Bose-Hubbard Model --- p.17 / Chapter 3.2 --- Two-polariton Bound States in the JCH Model --- p.19 / Chapter 3.2.1 --- Bound State Eigenvectors --- p.24 / Chapter 3.2.2 --- Bound State Eigenvalues --- p.26 / Chapter 3.2.3 --- Critical Coupling --- p.28 / Chapter 3.2.4 --- Analytic Approximations in Strong Coupling Regime n≫k --- p.30 / Chapter 3.3 --- Dynamics of Two Excitations in Strong Coupling Regime --- p.33 / Chapter 3.3.1 --- Initial Condition: --- p.33 / Chapter 3.3.2 --- Initial Condition: Superposition of j2; gin in Gaussian Distribution --- p.34 / Chapter 3.3.3 --- Initial Condition: Superposition of j1; gin j1; gim in Gaussian Distribution --- p.39 / Chapter 3.3.4 --- Initial Condition: Superposition of j1;+in j1; ¡im in Gaussian Distribution --- p.39 / Chapter 4 --- JCH Model in a Two-cavity Con¯guration --- p.41 / Chapter 4.1 --- Generation of SchrÄodinger's Cat State: Numerical Simulation --- p.41 / Chapter 4.2 --- Generation of SchrÄodinger's Cat States: Analytic Solution --- p.45 / Chapter 4.2.1 --- Estimation of Optimum Parameters --- p.53 / Chapter 4.3 --- Coherent States as Initial Conditions --- p.55 / Chapter 5 --- Decoherence of a Weakly Driven JCH Model --- p.60 / Chapter 5.1 --- Master Equation --- p.60 / Chapter 5.2 --- Driven JCH Model: N-cavity Configuration --- p.61 / Chapter 5.2.1 --- One-excitation Approximation --- p.63 / Chapter 5.2.2 --- Simple Harmonic Oscillator Limit --- p.66 / Chapter 5.3 --- Driven JCH Model: Two-cavity Configuration --- p.69 / Chapter 6 --- Conclusion --- p.76 / Bibliography --- p.79

Thesis. 1978. M.S.--Massachusetts Institute of Technology. Dept. of Materials Science and Engineering. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Includes bibliographical references. / M.S.

Thesis (Sc.D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 1981. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Vita. / Bibliography: leaves 523-531. / by Glenn Thomas Hong. / Sc.D.

The behavior of water confined at the nanoscale plays a fundamental role in biological processes and technological applications, including protein folding, translocation of water across membranes, and water filtration and desalination processes. Remarkably, nanoscale confinement can drastically alter the properties of water. Understanding these changes in the physical behavior of water can provide new insights into many scientific questions and technical challenges. This thesis focuses on phase diagrams of water confined by graphene and graphene oxide. First, by performing Molecular Dynamic (MD) simulations, we constructed phase diagrams of water confined by graphene, a hydrophobic smooth surface. We found that the phase behaviors of water confined by graphene are complicated. In the phase diagram, monolayer square ice, bilayer square ice, liquid and vapor phases were presented. The non-monotonic cavitation pressures as a function of walls separations was unexpected. The values of cavitation pressures significantly deviated from the classical prediction for bulk water. Next, I moved to water under hydrophilic confinements. The first model used was a hydrophilic graphene-based surface where graphene C-water O interactions were tuned to create a hydrophilic surface but maintaining the geometry of the graphene. The phase diagram of water confined by hydrophilic graphene is presented. The extremely high magnitude of cavitation pressures found in this analysis suggests that energy can be converted efficiently from changes in relative humidity. Furthermore, the oscillation of cavitation pressures as a function of walls separations is relevant to water transportation. By randomly distributing hydroxyl groups on graphene, we saw similar cavitation pressures in a graphene oxide (GO) model.