Made available in DSpace on 2014-10-09T12:38:06Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:53Z (GMT). No. of bitstreams: 1 05639.pdf: 6476184 bytes, checksum: 3037d7c0ce96c51e46c15baa5bdd114c (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP / FAPESP:92/01672-4

En septembre 2015, le détecteur LIGO a permis la première observation directe d'ondes gravitationnelles. Ce détecteur terrestre, tout comme le détecteur européen VIRGO, est basé sur des technologies purement optiques. Ces instruments sont extrêmement sensibles autour de 100 Hz mais ils sont limités en dessous de quelques dizaines de Hertz par différentes sources de bruit (bruit sismique, bruit newtonien...) qui ne sont pas distinguables de l'effet du passage d'une onde gravitationnelle.Le principe du projet MIGA (Matter wave – laser based Interferometer Gravitation Antenna) est de coupler un interféromètre optique avec plusieurs interféromètres atomiques séparés spatialement afin d'être sensible aux ondes gravitationnelles à plus basse fréquence (typiquement autour d'un Hertz). Les atomes froids sont lancés en configuration fontaine et sont séparés, réfléchis et recombinés par des impulsions laser effectuées dans une cavité optique de 300 m de long. Ces impulsions bénéficieront du gain optique intrinsèque au résonateur, leur permettant d'atteindre la puissance nécessaire à la réalisation de transitions de Bragg d'ordre élevé, augmentant ainsi la sensibilité des interféromètres atomiques. Chaque interféromètre mesure le champ gravitationnel local et les vibrations des miroirs. Le bruit sismique est donc rejeté dans le cas de mesures différentielles et en reconstruisant spatialement le champ gravitationnel, on pourra différencier le signal dû aux ondes gravitationnelles, qui est un pur gradient à l'échelle de l'instrument, du bruit newtonien qui a une signature spatiale.Les cavités de 300 m seront installées au LSBB (Laboratoire Souterrain Bas Bruit) à Rustrel, où l'antenne MIGA pourra bénéficier d'un environnement remarquablement calme. Cet instrument permettra de cartographier le champ gravitationnel du site, ce qui sera d'un grand intérêt pour l'étude géologique du massif karstique.Dans le cadre de ce projet, nous réalisons au LP2N une expérience préliminaire dont l'objectif est de générer un interféromètre de 87Rb en cavités en configuration de fontaine atomique. Cet instrument utilise une nouvelle architecture de résonateurs optiques demi-dégénérés afin de manipuler les atomes de façon cohérente avec des impulsions de Bragg. / In September 2015, the LIGO detector realized the first direct observation of gravitational waves. This ground-based detector, as well as the European detector VIRGO, is based on purely optical technologies. These instruments are extremely sensitive around 100 Hz but they are limited below few tens of Hertz by several sources of cavity length noise (seismic noise, Newtonian noise...) that mimic the effect of a gravitational wave.The idea of the MIGA (Matter wave-laser based Interferometer Gravitation Antenna) is to couple an optical interferometer with several atom interferometers spatially separated to be sensitive to gravitational waves at lower frequencies (typically around 1 Hz). The cold atoms are launched in a fountain configuration and are then split, deflected and recombined by laser pulses generated in a 300 m long optical cavity. These laser pulses will benefit from the intrinsic optical gain of the resonator, which will allow them to reach the needed power to generate high order Bragg transitions and to improve the sensitivity of the atom interferometers. Each interferometer measures the local gravitational field and the motion of the cavity. The seismic noise can be rejected by doing differential measurements and by reconstructing the spatial gravitational field, one can differentiate the gravitational wave signal, which is a pure gradient at the scale of our instrument, from the Newtonian noise that has a spatial signature.The 300 m long cavities will be implemented at the LSBB laboratory in Rustrel, where the antenna will benefit from an outstanding low noise environment. This instrument will allow to map the gravitational field of the site which will be of great interest for the geological study of the karstic massif.In the frame of this project, a preliminary experiment is currently under construction at the LP2N laboratory whose objective is to generate a 87Rb interferometer in a cavity in a atomic fountain configuration. This instrument uses a new architecture of half-degenerate optical resonators to manipulate coherently the atomic cloud with Bragg transitions.

Durante a década de 90 diversos trabalhos surgiram com o objetivo de investigar a localização de estados quânticos. No contexto da eletrodinâmica quântica de cavidades é possível localizar estados não clássicos de um dado campo externo aplicado ao sistema, uma cavidade preenchida com um material não linear inicialmente preparada no estado de vácuo. Baseado em tal cenário, propomos uma técnica de localização de estados vibracionais de um íon armadilhado. Para isso, considera-se um íon armadilhado em um potencial confinante cujos graus de liberdade vibracionais e os níveis eletrônicos do íon são acoplados por meio de um laser. Uma vez gerada a interação, faz-se uso da técnica de engenharia de reservatórios a fim de obtermos uma equação mestra na qual haja uma dinâmica emissiva e absortiva, ambas artificiais, promovidas por liouvillianos engenheirados, obtidos utilizando o sistema auxiliar (níveis internos do íon). Decorre-se disso uma dinâmica efetiva, já que a emissão espontânea é sempre presente. Sob um certo regime de parâmetros, a competição entre os liouvillianos leva o sistema de interesse para um estado vibracional estacionário caracterizando a localização. A técnica apresentada é mais geral pois mesmo partindo-se de um estado de máxima mistura, a localização é atingida com alta fidelidade em relação ao estado vibracional almejado. O papel exercido pela engenharia de interações para o sucesso da localização é o principal fator motivador deste trabalho. / In the 90s several works arose in order to investigate the localization of quantum states. In the context of quantum electrodynamics of cavities, it is possible to find non-classical states of a given external field applied to the system employing, for instance, a cavity (initially prepared in the vacuum states) filled with a non-linear material. In such scenario, we propose a trapped ion vibrational state localization technique. Consider a trapped ion confined in a potential whose vibrational and electronic degrees of freedom are coupled through two laser fields. Once such interaction is generated, we make use of the reservoir engineering technique in order to obtain a master equation in which there is an artificial dynamics of emission and absorption promoted by engineerined liouvillians obtained by using an auxiliary system (internal ion levels) within an effective dynamics, since the spontaneous emission is always present. Under a certain set of parameters, competition among liouvillians takes the system of interest to a vibrational steady-state featuring localization. The presented technique is interesting because the steady-state is achieved with high fidelity with respect to the desired vibrational state even when starting with highly mixed states. The role presented by the engineered interactions is fundamental for a successful localization and it is the primary motivation of this work.

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Orientador: Hugo Enrique Hernandez Figueroa / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-13T12:10:33Z (GMT). No. of bitstreams: 1 Jeronimo_JoiceLuiz_M.pdf: 4749050 bytes, checksum: f44d530638f8a8121e171afc306321ff (MD5) Previous issue date: 2009 / Resumo: Este trabalho trata do estudo de máquinas industriais de solda por indução eletromagnética na faixa de Rádio Freqüência (RF), visando modelos robustos baseados em circuitos de parâmetros concentrados. Tipicamente as máquinas industriais para a aplicação em questão, apresentam três estágios; a fonte (geração de energia eletromagnética), blindagem e filtragem (através de uma cavidade), e alimentação da carga. Por se tratar de um equipamento de alta potência (dezenas de KVs), a fonte consiste num oscilador à válvula, na faixa 20-50 MHz. A fonte excita uma cavidade que ressoa e funciona como um armazenador dessa radiação eletromagnética e um filtro de freqüência. Finalmente a energia da cavidade é extraída através de dispositivo análogo a uma linha de transmissão e colocado em contato com a carga, isto é, o material a ser soldado. Os modelos propostos fazem uso de circuitos equivalentes eficientes obtidos para as válvulas e as cavidades eletromagnéticas utilizadas, e foram validados através de testes experimentais minuciosos aplicados a uma máquina de fabricação nacional, líder de vendas no mercado latino-americano. / Abstract: This work is related to the study of electromagnetic weld industrial machines operating in radio frequency band aiming robust models based on concentrated parameters circuits. Typically, those machines have three steps: the power source (electromagnetic energy generation), shielding and filtering (through cavity) and load power supply. Since the equipment demands high power (dozen of KVs), the power source consists of a valve oscillator of 20-50MHz bandwidth. The power source excites a cavity that resonants and works like a storing of electromagnetic radiation and a frequency filter. Finally, the cavity energy is extracted through a device that works like a transmission line and sent to the load, that means, the material to be welded. The proposed models use efficient equivalent circuits found for the machine valves and cavities, and they were validated through detailed experiments on a machine produced for a Brazilian company, leader of the Latin American market. / Mestrado / Telecomunicações e Telemática / Mestre em Engenharia Elétrica

A invenção da Tomografia Computadorizada revolucionou o método de diagnóstico. Apesar de ser um exame de custo elevado, sua confiabilidade é de grande valia. Na década de noventa foram descritos os primeiros relatos da tomografia computadorizada Cone Beam para o uso na Odontologia. Esses aparelhos de tomografia computadorizada por feixe cônico, Cone Beam ou volumétrica são mais compactos, de menor custo e com menor tempo de exposição à radiação ao paciente, quando comparados aos aparelhos de tomografia computadorizada médica ou Fan Beam. Diante da grande utilização de implantes osseointegrados, algumas dificuldades foram despontando, visto que também paralelamente a este, os defeitos ósseos necessitavam de correção. Então os enxertos ósseos ou biomateriais de enxertia passaram a ser a alternativa que possibilitava a correção dessas perdas ósseas. Com o objetivo de estudar e avaliar qualitativamente os biomateriais de enxertia, inseridos em alvéolos dentais, em mandíbulas de suínos, por meio da tomografia computadorizada Cone Beam, utilizou-se de 20 mandíbulas dissecadas de porco, dos quais foram extraídos quatro dentes e nesses alvéolos foram introduzidos quatro biomateriais de enxertia de composições diferentes, com propriedades físico-químicas distintas, forma física, origem e de classificações diferentes. As mandíbulas de suínos foram submetidas a um exame de tomografia computadorizada volumétrica. As imagens obtidas foram avaliadas por um Software específico. Os resultados mostraram que não existiu diferença entre os cortes C (corte coronal) e S (corte sagital) e entre os cortes SS (corte parassagital) e o corte PAN (corte panorâmico), sendo que os corte C e S tiveram maior observação e os cortes SS e PAN, foram os de menor observação. Quanto ao material M-C (GenPhos HA TCP®, G 50, 0.5cc) foi o que obteve maior média de observação (com média 1, 81) enquanto que o M-B (OrthoGen®, G 75, 0.5cc) foi o mais difícil de ser observado, nos contes C (corte coronal) e S (corte sagital). Em relação a homogeneidade os materiais M-B (OrthoGen®, G 75, 0.5cc) e M-D (GenOx Inorg Esponjoso®) não apresentaram diferenças significativas, sendo portanto os materiais considerados menos homegêneos, quando se referem a densidade; observados nos cortes C (corte coronal) e S (corte sagital). Já os materiais M-C (GenPhos HA TCP®, G 50, 0.5cc) e M-A (Biogran® 300-350m, 50-45 mesh) segundo os p-valores não foram considerados estatisticamente diferentes, portanto os materiais que apresentaram as imagens mais homogêneas, igualmente aos demais materiais, foram observados nos cortes C (corte coronal) e S (corte sagital). O corte PAN (corte panorâmico) com média 1,43, foi a imagem que permitiu uma melhor observação dos biomateriais de enxertia. Todos os avaliadores afirmaram que identificaram o alvéolo ou o biomaterial de enxertia considerando a referência anatômica (lâmina dura). / The invention of Computed Tomography has radically changed the method of diagnosis. Even though it is a high-cost exam, its reliability is really worth it. The first reports about the use of Cone-Beam Computed Tomography in Dentistry were described during the 1990s. These conic bundle, Cone-Beam or volumetric computed tomography devices are more compact, less expensive and provide the lowest radiation dose for the patient when compared to other medical or Fan-Beam computed tomography devices. Once there has been a wide use of osseointegrated implants, some difficulties have emerged as, in parallel to this, there were some bone defects that required correction. Therefore, bone graftings or biomaterials for graftings have become an alternative that allowed correcting bone losses. With the objective to study and evaluate qualitatively the grafting biomaterial inserted pig mandibles dental cavities by Cone-Beam computed tomography, it was used 20 dissected pig mandibles, from which four teeth have been extracted and four biomaterial graftings of different compositions, different physical-chemical properties, physical shape, origin and classifications have been inserted into those cavities. The pig mandibles were submitted to a volumetric computed tomography. Images were evaluated by specific software. Results showed that there was no difference between C (coronal section) and S (sagittal section) sections, and between SS (parassagittal section) and PAN (panoramic section) sections. C and S sections had more observation and SS and PAN sections were the ones with less observation. Concerning the material, M-C (GenPhos HA TCP®, G 50, 0.5cc) was the one that obtained the highest observation average (1,81) while M-B (OrthoGen®, G 75, 0.5cc) was the most difficult to be observed on C (coronal) and S (sagittal) sections. About the homogeneity of materials, M-B (OrthoGen®, G 75, 0.5cc) and M-D (GenOx Inorg Esponjoso®) did not show significant differences, being, therefore, the materials considered the least homogeneous regarding density; observed in C (coronal) and S (sagittal) sections. According to p-values, materials M-C (GenPhos HA TCP®, G 50, 0.5cc) and M-A (Biogran® 300-350m, 50-45 mesh) were not considered statistically different. Thus the materials that presented the most homogeneous images, as well as the other materials, were observed in C (coronal) and S (sagittal) sections. The PAN (panoramic) section, with an average of 1,43, was the image that allowed the best observation of the grafting biomaterials. All evaluators affirmed to have identified the cavity of the grafting biomaterial considering the anatomic reference (hard slide).

RESUMO Esmalte e dentina são substratos dentários simultaneamente presentes na maioria das cavidades preparadas para restaurações adesivas, mas não há estudos sobre a morfologia regional das interfaces de união em uma mesma cavidade. Adesivos autocondicionantes incorporam a smear layer na camada híbrida e, conseqüentemente, as bactérias que porventura estejam presentes nela. Recentemente surgiu um adesivo autocondicionante com propriedades antibacterianas, conferidas pela adição de MDPB ao primer, mas ainda há poucas pesquisas sobre a morfologia da interface de união produzida por este material. Este estudo teve por objetivo analisar a morfologia de interfaces de união em diferentes regiões de cavidades MOD, através de microscopia eletrônica de varredura - MEV, em casos com adesivos autocondicionantes com ou sem MDPB. Como controle, foram usados dois adesivos de frasco único, cuja morfologia está amplamente descrita na literatura. Foram preparadas dezesseis cavidades Classe II em terceiros molares humanos hígidos, que foram restauradas com Z250 e um dos seguintes sistemas adesivos, aplicados segundo instruções dos fabricantes: ABF, Clearfil SE Bond, Single Bond e Prime & Bond NT. Após vinte e quatro horas de armazenamento em água destilada a 37ºC, os dentes restaurados foram seccionados em três planos de corte e preparados para análise em MEV, segundo o protocolo descrito por Montes et al. (2001). Também foram preparadas réplicas dos espécimes em resina epóxica. A morfologia das interfaces de união apresentou diferenças dependendo da região observada e também do tipo de sistema adesivo. A presença de MDPB não alterou a morfologia da interface de união dos adesivos autocondicionantes. A morfologia das interfaces de união em esmalte revelou perfeita adaptação ao substrato para todos os produtos estudados. / ABSTRACT Enamel and dentin are dental substrates simultaneously present in most cavity preparations for bonded restorations. Yet, no study can be found regarding the regional morphology of bonding interfaces present in a same cavity. Self-etching adhesive systems incorporate the smear layer into the formed hybrid layer, and consequently bacteria that might be present. Recently a self-etching system with antibacterial properties provided by the addition of MDPB was introduced in the market, but there is still little research on the interfacial morphology obtained with this material. This study aimed at analyzing the interfacial morphology in different areas of MOD cavities prepared using adhesive systems either with or without MDPB, by means of Scanning Electron Microscopy – SEM. Two single bottle adhesive systems whose morphology is widely described in the literature were used as control groups. Sixteen class II cavities were cut in sound human molars and restores using Z250 resin composite and one of the following adhesive systems, applied strictly according to the manufacturers’ instructions: ABF, Clearfil SE Bond, Single Bond and Prime & Bond NT. After 24-hour storage in distilled water at 37ºC, the teeth were sectioned in three directions and prepared for SEM analysis according to the protocol described by Montes et al. (2001). Replicas were also obtained from each specimen using epoxy resin. The interfacial morphology showed differences depending on the observed area, and also on the adhesive system. The presence of MDPB did not alter the interfacial morphology of the bonded interfaces obtained with self-etching adhesive systems. Bonded interfaces in enamel revealed perfect adaptation for all studied materials.

A resonant microwave cavity technique was employed to study the dielectric behavior of some polar and non-polar liquids near the phase transition temperatures at microwave frequencies of 7.2, 9.2 and 10.1 GHz. The Slater perturbation equations for a resonant microwave cavity are briefly discussed to show that the above technique can be used to determine both the real and imaginary parts of dielectric response. Abrupt changes in dielectric response were observed near the phase transition temperatures for the polar liquids studied in this investigation. The dielectric relaxation phenomenon in liquids has been treated as a chemical rate process and the abrupt change in the dielectric response of the liquids near phase transition temperatures is shown to be related to the dramatic changes in the free energy of activation of the molecules. Some values of the free energy of activation were deduced for the various compounds from data obtained in this investigation.

Omniphobic surfaces, which repel polar and non-polar liquids alike, have proven of value in a myriad of applications ranging from piping networks, textiles, food and electronics packaging, and underwater drag reduction. A limitation of currently employed omniphobic surfaces is their reliance on perfluorinated coatings/chemicals, increasing cost and environmental impact and preventing applications in harsh environments. Thus, there is a keen interest in rendering conventional materials, such as hydrocarbon-based plastics, omniphobic by micro/ nanotexturing rather than via chemical makeup, with notable success having been achieved for silica surfaces with doubly reentrant pillars (DRPs). We discovered a critical limitation of DRPs – they catastrophically lose superomniphobicity in the presence of localized physical damages/defects or on immersion in wetting liquids. In response, we pioneered bio-inspired gas-entrapping microtextured surfaces (GEMS) architecture composed of doubly reentrant cavities (DRCs). DRCs are capable of robustly entrapping air when brought into contact with liquid droplets or on immersion, which prevents catastrophic wetting transitions even in the presence of localized structural damage/defects. This dissertation presents our multifaceted research on DRCs via custom-built pressure cells, confocal laser scanning microscopy, environmental scanning electron microscopy, contact angle goniometry, high-speed imaging, and upright optical microscopy. Specific accomplishments detailed in this thesis include: (i) the microfabrication protocols for silica GEMS developed at KAUST; (ii) the characterization of GEMS’ omniphobicity via apparent contact angles and immersion; (iii) the demonstration of ~ 1000,000,000% delays in wetting transitions in DRCs compared to those in simple cavities (SCs) under hexadecane; (iv) a proposal for immersion of surfaces as a criterion for assessing their omniphobicity in addition to apparent contact angles; (v) effects of surface chemistry, hydrostatic pressure, and cavity dimensions on Cassie-to-Wenzel transitions in DRCs and SCs; (vi) the demonstration of “breathing” (liquid-vapor) interfaces in GEMS under fluctuating hydrostatic pressures; and (vii) the demonstration of directional wetting transitions in DRCs (or cavities in general) arranged in one- and two-dimensional lattices. The last chapter in the thesis presents future research directions such as breathing surfaces capable of preempting vapor condensation and gas replenishment.

[pt] A optomecânica é um campo em crescimento que estuda sistemas nos quais luz e movimento mecãnico estão acoplados por meio de pressão de radiação. Neste trabalho apresentamos a teoria básica acerca de cavidades ópticas e pinças ópticas, duas importantes ferramentes frequentemente utilizadas em experimentos de optomecânica, bem como suas implementações práticas. No que diz respeito a cavidades ópticas, nós apresentamos a implementação de cavidades de Fabry Pérot formadas por um espelho plano e um espelho esférico e de cavidades formadas por dois espelhos esféricos, tanto na configuração confocal como na configuração não confocal, e comparamos a performance dessas diferentes cavidades. No que diz respeito a pinças ópticas, nós apresentamos uma pinça óptica capaz de aprisionar esferas micrométricas em um meio aquoso e a usamos para estudar o movimento de partículas aprisionadas. / [en] Optomechanics is a growing field that studies systems where light and mechanical motion are coupled via radiation pressure. In this work, we present the basic theory regarding optical cavities and optical tweezers, two important tools that are often used in optomechanical setups, as well as their experimental implementations. On the subject of optical cavities, we present the implementation of Fabry Pérot cavities formed by one plane mirror and one spherical mirror and cavities formed by two spherical mirrors, both on the confocal and on the non-confocal configuration, and compare the performance of these different cavities. On the subject of optical tweezers, we present an optical tweezer capable of trapping micro-spheres in a water medium and use it to study the movement of trapped particles.