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The goal of this project is to obtain quantitative images of the lens and the ciliary body to validate EVAS-II (Second generation Ex Vivo Accommodation Simulator). To accomplish this goal it was necessary to develop methods, instrumentation and image processing techniques to acquire 3D images in EVAS-II, using UBM (Ultrasound Bio Microscope), and to apply these techniques to non-human primate eyes. The lens studies included measurement of speed of sound in the lens to reconstruct accurate images of the lens, development of instrumentation to measure the un-distorted lens shape and development of a mathematical model to quantify the whole lens shape. Speed measurements showed that the speed of sound exhibits a gradient profile in the equatorial plane, similar to refractive index and protein distributions in the lens. Lens shape measurements showed that the UBM can be used to accurately measure thickness, diameter, cross-sectional area, volume and surface area of the lens. The ciliary body studies included development of instrumentation and algorithms to obtain 3-D images of tissue in EVAS-II and development of methodology to quantify ciliary body movement during stretching. Studies showed that the accommodation process in young baboon eyes in EVAS-II is comparable to the in vivo process in rhesus monkeys. The UBM can be used to obtain reliable quantitative information about the lens and the ciliary body. 3-D UBM enables monitoring of ciliary body motion of the entire accommodative apparatus.

This master’s thesis deals with the construction and realization of an ultrasound anemo- meter. Individual types of anemometers are compared in this thesis, including mechanical, thermo anemometer and ultrasound anemometer. Different construction renderings and measurement principles of ultrasonic anemometers are analyzed. In addition, an experi- mental method of measuring the speed of sound by phase shift between two transmitting frequency is described in the document. This thesis includes the design of an control unit and the realization of a simple prototype of an ultrasonic anemometer. Experimental confirmation of the characteristics of the ultrasound anemometer is the last part of the document.

The subject of the submitted thesis „Low pressure water hammer“ is handling the problems of dynamic conduct of water in low pressures. In this work are developed problems of the effect of changing pressure on the speed of sound in liquid. The problem is solved in the time domain using the Lax - Wendroff method in the theoretical analysis. At the end the mathematical model solved using Lax - Wendroff method is confront with the experiment.

This thesis aims to investigate the acoustic properties of ultrasound contrast agents (UCAs) at high ultrasound frequencies. In recent years, there has been increasing development in the use of high frequency ultrasound in the fields of preclinical, intravascular, ophthalmology and superficial tissue imaging. Although research studying the acoustic response of UCAs at low diagnostic ultrasonic frequencies has been well documented, quantitative information on the acoustical properties of UCAs at high ultrasonic frequencies is limited. In this thesis, acoustical characterisation of three UCAs was performed using a preclinical ultrasound scanner (Vevo 770, VisualSonics Inc., Canada). Initially the acoustical characterisation of five high frequency transducers was measured using a membrane hydrophone with an active element of 0.2 mm in diameter to quantify the transmitting frequencies, pressures and spatial beam profiles of each of the transducers. Using these transducers and development of appropriate software, high frequency acoustical characterisation (speed and attenuation) of an agar-based tissue mimicking material (TMM) was performed using a broadband substitution technique. The results from this study showed that the acoustical attenuation of TMM varied nonlinearly with frequency and the speed of sound was approximately constant 1548m·s-1 in the frequency range 12-47MHz. The acoustical properties of three commercially available lipid encapsulated UCAs including two clinical UCAs Definity (Lantheus Medical Imaging, USA) and SonoVue (Bracco, Italy) and one preclinical UCAs MicroMarker (untargeted) (VisualSonics, Canada) were studied using the software and techniques developed for TMM characterisation. Attenuation, contrast-to-tissue ratio (CTR) and subharmonic to fundamental ratio were measured at low acoustic pressures. The results showed that large off-resonance and resonant MBs predominantly contributed to the fundamental response and MBs which resonated at half of the driven frequency predominantly contributed to subharmonic response. The effect of needle gauge, temperature and injection rate on the size distribution and acoustic properties of Definity and SonoVue was measured and was found to have significant impacts. Acoustic characterisations of both TMM and UCAs in this thesis extend our understanding from low frequency to high frequency ultrasound and will enable the further development of ultrasound imaging techniques and UCAs design specifically for high frequency ultrasound applications.

Dans le cadre d’une réduction d’émission de gaz à effets de serre, la possibilité d’introduire une quantité de biodiesel dans les diesels dits « traditionnels », c’est-à-dire issus des énergies fossiles est une possibilité envisagée par les groupes pétroliers. Cependant, la connaissance des propriétés thermophysiques des fluides sous pression est mince, que ce soient des mélanges ou des corps purs, où peu de données expérimentales existent. Dans le cadre de cette thèse, une nouvelle sonde de mesures des propriétés acoustiques sous pression a été développée dans le but de réaliser des mesures de toutes les propriétés thermophysiques en utilisant un volume d’échantillon minimum grâce à la fois, à une technique de mesure de vitesse du son via l’utilisation de transducteurs piézoélectriques et de viscosité via l’utilisation de cristaux de quartz. Si cette thèse s’inscrit dans une démarche visant à travailler sur les biodiesels et leurs corps purs, la sonde développée au cours de ces trois ans est amenée à être expérimentée dans un avenir proche, sur des fluides directement issus de champs pétroliers et/ou de synthèses, sous pression afin de déterminer des propriétés thermophysiques mais également des équilibres de phase sous pression. / Key words : speed of sound, compressibility, density, viscosity, biodiesel, methyl and ethyl esters, pressure.In the context of reduction of exhaust gases, the possibility to introduce a quantity of biodiesel inside traditional diesel from fossils fuels is one of the step taken by petroleum societies. However, the knowledge of thermophysical properties of fluids is scant, for mixture and pure compounds, where few data exist. In this work, a new measurement probe under high pressure, has been developed in the aim to realize measurements of thermophysical properties using a minimum volume sample, thanks a technique of measurements of speed of sound using piezoelectric transducers and viscosity using quartz crystals. If this thesis is focused on the work on the biodiesels and their pure components, this probe will be experimented, in a near future, on fluids directly from oil fields and/or syntheses ones under pressure, in the aim to determine thermophysical properties but also phase equilibria.

>Magister Scientiae - MSc / We begin by finding a system of differential equations for the background and linearly perturbed variables in the standard, ɅCDM model, using the Einstein Field Equations, and then solving these numerically. Later, we extend this to dynamical dark energy models parameterised by an equation of state, w, and a rest frame speed of sound, cs. We pay special attention to the large-scale behaviour of Δm, the gauge invariant, commoving matter density, since the approximation Δm ≃ δm, where δm is the longitudinal gauge matter density, is more commonly used, but breaks down at large scales. We show how the background is affected by w only, so measurements of perturbations are required to constrain cs. We examine how the accelerated expansion of the universe, caused by dark energy, slows down the growth rate of matter. We then show the matter power spectrum is not in itself useful for constraining dark energy models, but how redshift-space distortions can be used to extract the growth rate from the galaxy power spectrum, and hence how redshift-space power spectra can be used to constrain different dark energy models. We find that on small scales, the growth rate is more dependent on w, while on large scales, it depends more on cs.

Orientadores: Pedro Luiz Onófrio Volpe, Ricardo Belchior Tôrres / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-26T22:29:35Z (GMT). No. of bitstreams: 1 Hoga_HeloisaEmi_D.pdf: 3636468 bytes, checksum: 5e4d8bd5f23dc45b0e386f59f4dd3f74 (MD5) Previous issue date: 2015 / Resumo: Propriedades excesso têm sido um caminho qualitativo e quantitativo para predizer o desvio da idealidade de soluções líquidas binárias. Além disso, as grandezas excesso têm sido usadas para desenvolver modelos e novas teorias de soluções. Neste trabalho teve como objetivo o estudo experimental de grandezas volumétricas, viscosimétricas, acústicas e das entalpias excesso de soluções líquidas binárias de água + etanol, ou + etileno glicol, ou + dietileno glicol, ou + trietileno glicol, ou + polietileno glicol 200 (PEG 200), ou + polietileno glicol 300 (PEG 300), ou + polietileno glicol 400 (PEG 400), ou + polietileno glicol 600 (PEG 600), ou + glicerol em função da composição, a diferentes temperaturas e à pressão atmosférica. Os dados de densidade e de velocidade do som foram determinados usando um densímetro e velocímetro (Anton Paar, Modelo DSA 5000). Os valores de viscosidade foram determinados usando um viscosímetro (Anton Paar, Modelo SVM 3000). Os valores da entalpia foram determinados utilizando um microcalorímetro (Thermal Activity Monitor, Titration mode, LKB2277, Thermometric). As temperaturas estudadas foram de 293,15, 298.15, 303,15 e 308,15 K. Somente a entalpia foi estudada a 298,15 K. Os resultados experimentais foram usados para calcular o volume molar excesso, o desvio da compressibilidade isentrópica, o desvio da viscosidade, a energia de Gibbs de ativação excesso e a entalpia molar excesso. As propriedades excesso foram correlacionadas usando os polinômios do tipo Redlich-Kister e Myers-Scott. Os resultados foram comparados e discutidos com base nas interações intermoleculares entre os componentes estudados / Abstract: Excess properties have been a qualitative and quantitative way to predict ideality deviation of liquid binary mixtures. Moreover the excess properties have been used to development molecular theories and new solution models. In this study, density, speed of sound, viscosity and enthalpy of binary mixtures of water + ethanol, or + ethylene glycol, or + diethylene glycol, or + triethylene glycol, or + polyethylene glycol 200, or + polyethylene glycol 300, or + polyethylene glycol 400, or + polyethylene glycol 600, or + glycerol have been determined as a function of composition at several temperatures and atmospheric pressure. The density and speed of sound data were determined using a density and sound velocity meter (Anton Paar, Model DSA 5000) The viscosity data was determined using a viscometer (Anton Paar, Model SVM 3000). The enthalpy date was determined using a microcalorimeter (Thermal Activity Monitor, Titration mode, LKB2277, Thermometric). The temperatures studied were 293.15, 298.15, 303.15 and 308.15 K. Only enthalpy data was measured at 298.15 K. The experimental results have been used to calculated the excess molar, deviations in isentropic compressibility, deviations in viscosity, excess Gibbs free energy of activation of viscous flow and excess molar enthalpy. The excess properties were correlated by using a Redlich-Kister and Myers-Scott polynomial equation. The results were discussed on the basis of intermolecular interactions between the components of the analyzed mixtures / Doutorado / Físico-Química / Doutora em Ciências

This thesis describes the design and evaluation process of experimental measuring of the amount of bubbly air in water. The measuring principle is based on the assessment of speed of sound, which is dependent on the presence of air. Results were compared with the concentration calculated from the calibrated air flow through nozzles.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A descoberta de reservatórios de petróleo na camada do pré-sal abriu novas perspectivas para a economia brasileira. A grandes profundidades, com elevado teor de CO2 e submetidos a altas pressões e temperaturas, a exploração de petróleo das camadas de pré-sal constitui um considerável desafio tecnológico. Neste contexto, o conhecimento dos coeficientes de compressibilidade são fundamentais para o estudo do comportamento termodinâmico e escoamento dos fluidos destes campos de produção. Com este objetivo, foram determinadas experimentalmente nesta dissertação a massa específica e a velocidade do som de sistemas envolvendo quatro hidrocarbonetos puros: n-decano, n-hexadecano, decalina e tetralina, assim como para sistemas multicompostos envolvendo estes hidrocarbonetos e para uma amostra de condensado de petróleo. Os resultados obtidos permitiram o cálculo dos coeficientes de compressibilidade isentrópica, isotérmica e isentálpica. É apresentada uma avaliação sobre a capacidade de se correlacionar dados experimentais de velocidade do som aos dados calculados pelas equações de estado de Peng-Robinson e Lee-Kesler com regras de mistura: (i) Spencer e Danner e (ii) Lee-Kesler / The discovery of oil reservoirs in the pre-salt layer has opened new perspectives for Brazilian economy. In deep waters, with high levels of CO2 and subjected to high pressures and temperatures, the oil exploration in the pre-salt layer is a considerable technological challenge. In this context, knowledge of compressibility coefficients and phase equilibrium data are essential for studying the thermodynamic behavior and flow in these oil fields. With this objective, experimental data were obtained for density and sound velocity in systems involving four pure hydrocarbons: n-decane, n-hexadecane, decalin and tetralin, as well as in multi-component systems involving these hydrocarbons, and in a sample of oil condensate. The results obtained allowed the calculation of isentropic, isothermal and isenthalpic compressibility coefficients. An evaluation on the ability to correlate experimental data of sound velocity with data calculated from Peng-Robinson and Lee-Kesler equations of state with mixing rules: (i) Spencer and Danner and (ii) Lee-Kesler is presented