Submitted by Tiago Carneiro Gomes (tiagogomes.prof@gmail.com) on 2018-06-30T16:46:33Z No. of bitstreams: 1 Gomes_T_C_tese_de_Doutorado.pdf: 5694002 bytes, checksum: 22bc5318ec502694cd7a4a087cec549f (MD5) / Approved for entry into archive by Lucilene Cordeiro da Silva Messias null (lubiblio@bauru.unesp.br) on 2018-07-02T19:06:37Z (GMT) No. of bitstreams: 1 gomes_tc_dr_bauru.pdf: 5485212 bytes, checksum: 22c574afd417cd26b3380c78e8274909 (MD5) / Made available in DSpace on 2018-07-02T19:06:37Z (GMT). No. of bitstreams: 1 gomes_tc_dr_bauru.pdf: 5485212 bytes, checksum: 22c574afd417cd26b3380c78e8274909 (MD5) Previous issue date: 2018-03-27 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Transistores de filme fino de ZnO, cujo desempenho depende das condições de preparação da camada de ZnO e do dielétrico de gate, tem sido aplicados como sensores de radiação ultravioleta (UV), visando prevenir danos à saúde da pele. Este trabalho tem como objetivo a fabricação de transistores de ZnO/Al2O3, mediante o estudo simultâneo dos parâmetros relacionados à preparação das camadas de ZnO e Al2O3, bem como, o de transistores com dielétrico padrão (ZnO/SiO2) submetidos a diferentes condições de funcionamento. Estes estudos visam encontrar quais condições viabilizam as aplicações dos transistores como sensor UV. Os experimentos englobam a deposição de filmes de ZnO tanto por sputtering de um alvo de ZnO, quanto por spray pirolise de uma solução de acetato de zinco. O dielétrico SiO2 foi obtido comercialmente, enquanto que o Al2O3 foi crescido por anodização. Os transistores foram fabricados em diversas condições, as quais foram estabelecidas pelos métodos de planejamento experimental Taguchi e Plackett-Burman. As respostas das caracterizações foram interpretadas por técnicas de estatística (ANOVA). Os resultados demonstram que Al2O3 otimizado exibe correntes de fuga de até 10E-10 A e constante dielétrica de ~13. A identificação dos parâmetros mais importantes na preparação de filmes de ZnO por spray pirólise, permitiram produzir transistores de ZnO/Al2O3 com mobilidades de ~4,5 cm2/Vs. Os sensores UV, usando transistores de ZnO/SiO2 apresentaram mobilidades de 0,1 a 12 cm2/Vs, e indicaram que a sensibilidade do sensor UV depende de parâmetros relacionados as condições de operação do dispositivo. Portanto, mostra-se que é fundamental a compreensão dos parâmetros envolvidos na produção dos dispositivos, pois isto permite refinar o processo na busca pela alta performance de dispositivos de baixo custo, bem como, otimizar os dispositivos para aplicações como sensor de radiação UV. / ZnO thin film transistors have been applied as ultraviolet (UV) radiation sensors in order to prevent damage to skin's health. However, the performance of ZnO transistor depends on the preparation conditions of both ZnO layer and gate dielectric. This work aims to produce and evaluate ZnO/Al2O3 transistors by studying simultaneously the parameters regarding the preparation of ZnO and Al2O3 layers, as well as the fabrication of ZnO transistors with a standard dielectric (ZnO/SiO2), under different conditions of working. It is intended to investigate the conditions to apply ZnO transistors as UV sensor. The experiments involve the deposition of ZnO films by sputter coating and spray pyrolysis of a solution of zinc acetate. SiO2 dielectric was commercially purchased, while Al2O3 was grown by anodization. The transistors were fabricated under different conditions, which were established by both experimental design Taguchi and Plackett-Burman methods. The responses from the characterization were interpreted by statistical techniques (ANOVA). The results showed that optimized Al2O3 films exhibit leakage current until 10E-10 A and dielectric constant of ~13. It was essential to identify the most important parameters regarding to preparation of ZnO films by pyrolysis spray in order to fabricate ZnO/Al2O3 transistors with mobilities of ~4,5 cm2/Vs. UV sensors based on ZnO/SiO2 transistors showed mobilities from 0,1 to 12 cm2/Vs and demonstrated that the sensitivity of the UV sensor depends on parameters related to working conditions. Therefore, it is of great importance the understanding of the parameters involved in the production of the devices, as it allows to refine the process in the search for the high performance of low cost materials as well as optimize the device for application as UV sensor. / FAPESP: 2014/13904-8

The increasing level of the UV-B irradiation due to depleting of the ozone layer is considered to be one of the causes of global amphibian declines. The UV-B radiation causes damage to the DNA in the nuclei of the skin cells and their eventual death. In many amphibian species there was found a negative influence of the UV-B radiation on the hatching success of tadpoles and their subsequent viability. It has been assumed that tadpoles are able to actively avoid places with the higher exposure of the UV-B radiation thanks to their locomotion. In this experiment tadpoles could have chosen between a zone with the UV radiation (UV-B and UV-A) and without the UV radiation. The tadpoles have not been exposed to the UV radiation before the measurement started. The location of the tadpoles during the measurement was recorded by CCD camera. A computer program EthoVision then evaluated the time that these tadpoles spent in each of the zones and the total path length these tadpoles has swum in the zones. The measurements were performed for two groups of tadpoles differing in age to determine whether the level of development may affect the tadpoles' preference to the UV radiation. The tadpoles in both groups spent more time in the zone without the UV radiation. The tadpoles in the more advanced development phase have spent 7 times more time in average in the zone without the UV radiation than in the zone with it. The tadpoles from the second group have spent in average 2.5 times more time in the zone without the UV radiation than in the zone with the UV radiation. The total swimming path length of advanced tadpoles was almost 2.5 times longer in the zone without the UV radiation than in the zone with the UV radiation. Conversely, the total path length of younger tadpoles did not significantly differ between the zones. The total time spent in the zones with / without the UV radiation did not differ between the groups of tadpoles. Also the total path length did not differ between the groups in the zone with the UV-B radiation. However, the total path length of tadpoles had differed between groups in the zone without the UV radiation.

Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Candidate: Tereza Morávková Supervisor: Assoc. Prof. Přemysl Mladěnka, Pharm.D., Ph.D. Title of Thesis: Assessment of the complex stoichiometry of the active dexrazoxane metabolite ADR-925 with iron and copper by the standard Job'smethod Iron and copper are important trace elements which participate on many physiological processes in humans. Their kinetics in the organism is tightly regulated since both lack or excess of these elements are associated with pathological states. Free ions of iron and copper can catalyse reactive oxygen species (ROS) production and hence cause damage to proteins and DNA. Imbalance in these metals is linked with diabetes, cardiotoxicity, cirrhosis of the liver and neurodegenerative diseases as Alzheimer's disease or Parkinson's disease. Dexrazoxane is a drug with documented protecting effect against cardiotoxicity of anthracyclines. A former theory associated its protective effects against these cytotoxic drugs with the iron-chelating properties of its active metabolite ADR-925. The goal of this diploma thesis was to explore if ADR-925 is able to chelate Fe2+ , Fe3+ , Cu+ a Cu2+ ions at physiologically and pathophysiologically relevant pH values (4,5; 5,5; 6,8 and 7,5) and...

Ultraviolet –B (UV-B) radiation is an abiotic stress that has significant effects on plant growth, development, and gene regulation. Due to the depletion of the stratospheric ozone layer over the past several decades, the amount of UV-B light that is reaching the earth’s surface has significantly increased. As a result, research over the past few decades on the effects of UV-B light on plant growth, development, and the mechanisms that regulate a plant’s protection and survival against UV-B light has grown greatly. Brachypodium distachyon is a relatively new model system and one that has not been extensively studied. The aim of this study was to determine the UV-B dose time required to elicit a significant increase in phenolic content, while subsequently assessing protein production to qualitatively implicate whether or not the experimental dosage of UV-B administered was initiating a UV-B specific or non-specific response. In addition, this research annotated the genes that encode the protein sequences for UVR8 and CHS proteins to see if B. distachyon possessed the necessary proteins to undergo a UV-B specific response similar to that of Arabidopsis. The results of the study show that in response to artificial UV-B light, the dose time of UV-B required to elicit a significant increase in total phenolic content is 2 hours. The data also shows an increase in total protein content after 4 hours of UV-B exposure. In addition to the metabolic data, computational analysis of chalcone synthase (CHS) and UV-RESISTANCE LOCUS 8 (UVR8) revealed that there are seven genes in B. distachyon that encode the protein transcripts for CHS and CHS-like proteins, and two genes that code for UVR8 proteins. The results of this study suggest that the UV-B dose regimen used in this study may be initiating the non-specific UV-B signaling pathway. In addition, the presence of UVR8 and CHS protein sequences suggest that B. distachyon has the capacity to work through the UV-B specific signaling pathway.

Ces dernières décennies, des champs magnétiques ont été détectés dans quasiment tous les types d'étoiles. Ces découvertes ont donné lieu à des études innovantes sur la cartographie des champs magnétiques et leur impact sur l'environnement stellaire. Pour aller encore plus loin il est nécessaire d'allier la spectroscopie à la polarimétrie, dans l'UV et le visible. L'UV permet d'étudier les vents stellaires et l'environnement circumstellaire, tandis que le visible permet d'étudier la surface de l'étoile. La spectropolarimétrie UV+visible permet ainsi d'étudier les magnétosphères dans leur globalité. Ceci doit être fait sur au moins une période complète de rotation de l'étoile. Pour cela, il faut aller dans l'espace, à la fois pour atteindre le domaine UV et pour obtenir des observations ininterrompues sur une période de rotation stellaire complète. Le consortium international UVMag a été créé en 2010 pour discuter, étudier et promouvoir une mission spatiale pour l'étude des magnétosphères stellaires via de la spectropolarimétrie spatiale dans les domaines UV et visible simultanés. D'un point de vue technique, la spectroscopie spatiale pure, y compris dans l'UV, a déjà été utilisée avec succès, par exemple sur IUE, et serait très performante avec les détecteurs et les technologies disponibles aujourd'hui. Par contre, le spectropolarimètre UV+visible est la partie instrumentale la plus ambitieuse pour une future mission spatiale. En effet, alors que les français (en particulier le LESIA et l'IRAP) sont les spécialistes de ce type de spectropolarimètres dans le visible pour des télescopes au sol (comme ESPaDOnS au CFHT ou Narval au TBL), aucun instrument de ce type n'a encore été embarqué sur une mission spatiale, encore moins en UV. La première partie de ma thèse consistait à concevoir le design optique du module polarimétrique pour le spectropolarimètre de la mission Arago, dans le cadre du consortium UVMag. J'ai donc étudié et recherché différents concepts innovants qui pourraient s'adapter aux contraintes très particulières de cet instrument. En effet, les spécifications imposent l'utilisation d'un unique polarimètre pour tout le domaine spectral [119-888] nm. Les contraintes du spatial s'ajoutent à cela avec un besoin de compacité, légèreté et robustesse. Je me suis concentré sur 2 concepts de polarimètre différents, un premier basé sur le module de polarisation de l'instrument X-Shooter avec une modulation temporelle de la polarisation et une achromatisation des efficacités d'extraction des paramètres de Stokes et un second basé sur une modulation spatiale de la polarisation, permettant d'obtenir un polarimètre statique. J'ai adapté ces 2 concepts aux spécificités d'Arago et intégré ces 2 systèmes au design optique global de l'instrument. Le premier concept de modulation temporelle a été choisi pour l'instrument d'Arago qui a été soumis à l'ESA dans le cadre des appels Cosmic Vision M4 et M5. Dans un deuxième temps, l'objectif de ma thèse était de prouver la faisabilité des concepts évoqués plus haut. / Over the last few decades, magnetic fields have been detected in almost all kinds of stars. This led to innovative studies on the mapping of magnetic fields and their impact on the circumstellar environment. To go further, we need to use spectroscopy and polarimetry together, in the UV and visible range. The UV domain is used to study the stellar wind and stellar environment, whereas the visible range allows to study the surface of the star. UV+visible spectropolarimetry enables the global study of magnetospheres. This has to be done over at least one rotation period of the star. Therefore, we need to go to space in order to see the UV range and to obtain uninterrupted observations on a complete stellar rotation period. The international consortium UVMag has been created in 2010 to discuss, study and promote a space mission for the study of stellar magnetospheres using simultaneous UV and visible space spectropolarimetry. From the technical point of view, pure spectroscopy in space, both in the UV and visible ranges, has already been successfully used, for example on IUE, and would be very efficient with current detectors and technologies. On the other hand, the UV+visible spectropolarimeter is the most ambitious instrumental challenge for a future space mission. Indeed, until now, no such optical spectropolarimeter has flown on a space mission, despite the fact that the French (particularly the LESIA and IRAP laboratories) are the specialists for such instruments (such as ESPaDOnS at CFHT or Narval at TBL). The first part of my thesis consisted in elaborating the optical design of the polarimetric module for the spectropolarimeter of the space mission Arago, in the framework of the UVMag consortium. I studied various innovative concepts that could be adapted to the specific constraints of this instrument. The specifications indeed show the need for a unique polarimeter covering the complete spectral range [119-888] nm. Moreover, the usual compacity, lightness and robustness constraints of a space instrument are added to these specifications. I focused my work on 2 different polarimeter concepts, a first one based on the polarimetric module of the X-shooter instrument using a temporal modulation and an achromatization of the extraction efficiencies of the Stokes parameters, and a second one based on spatial modulation of the polarization, offering a static polarimeter. I adapted these 2 concepts to the specific constraints of Arago and integrated them to the complete optical design of the instrument. The first concept, using temporal modulation, has been chosen as the baseline for the instrument proposed to ESA for the Cosmic Vision calls M4 and M5. The goal was then to demonstrate the feasibility of the two concepts.

Avec l'objectif d'améliorer le rendement des lampes à excimères (Excilampe) à décharge à barrière diélectrique (DBD), un convertisseur en mode de courant, qui permet un ajustement précis de la puissance électrique injectée dans ce type des lampes, à été conçu et mis en oeuvre. Ce convertisseur fournit à la lampe un courant de forme d'onde carrée contrôlé au moyen de trois paramètres: l'amplitude, la fréquence et le rapport cyclique, pour obtenir un contrôle total de l'énergie électrique transmise à l'excilampe DBD. La mise en oeuvre intègre un transformateur élévateur comme interface entre la lampe et un commutateur. Les expériences démontrent le principe de fonctionnement de ce convertisseur, y compris les mesures de puissance du rayonnement UV. Les degrés de liberté du convertisseur sont utilisées pour analyser le comportement de la lampe sous différentes combinaisons de ces trois paramètres, et sont utilisés pour déterminer le point de fonctionnement optimal de la lampe. Ensuite, un convertisseur à résonance du type onduleur série, est proposé pour alimenter la lampe avec une grande efficacité électrique. Afin de contrôler effectivement la puissance de la lampe, le mode de fonctionnement de ce convertisseur utilise le mode de conduction discontinue et la commutation douce (ZCS), avec lequel on obtient aussi de faibles émissions électromagnétiques et l'on réduit les pertes de commutation. Les relations mathématiques obtenus à partir de l'analyse du diagramme de phase, ont été validées par des simulations et avec des résultats expérimentaux. Enfin, différentes topologies d'alimentations pour DBD sont comparées analytiquement et expérimentalement pour évaluer objectivement les avantages de chaque approche. Une des perspectives de ce travail est l'application de l'alimentation en créneaux pour l'étude de la performance d'autres types de réacteurs et d'excilampes DBD. / With the aim to provide a scientific tool for the enhancement of the Dielectric Barrier Discharge (DBD) Excimer Lamps (Excilamp) performance, a current-mode converter that allows an accurate adjustment of the electrical power injected into one of those lamps, is designed and implemented. With the proposed converter, the current supplied to the lamp has a square shape, controlled by means of three parameters: amplitude, duty cycle and frequency, which provides full control of the lamp electrical power. Implementation is made considering a step-up transformer interfacing the high-voltage lamp with the converter. Experiments demonstrate the operating principle of this converter, including UV power measurements for a DBD XeCl Excilamp. The capabilities of the converter are used to analyze the lamp behavior under different combinations of these three parameters, illustrating its capabilities for finding the optimal operating point. Then a series-resonant inverter for the supply of DBD) excilamp is proposed. In order to effectively control the lamp power, the operating mode of this converter combines discontinuous current-mode and soft-commutation (ZCS), obtaining as well low electromagnetic emissions, and reduced switching losses. The mathematical relationships obtained from state plane analysis, are validated with simulations and experimental results. Finally, several topologies of DBDs power supplies are compared analytical and experimentally to elucidate the advantages of each approach. After this work, one of the perspectives is the application of the square-shape supply in the performance study of other types of DBD excilamps and DBD reactors.

Submitted by DIEGO ROSSI null (rossi_diego@ig.com.br) on 2016-02-16T18:58:22Z No. of bitstreams: 1 Dissertação D.Rossi - FINAL.pdf: 4611767 bytes, checksum: 71f830e143f447c9e962c2305462a623 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-02-17T16:11:21Z (GMT) No. of bitstreams: 1 rossi_d_me_bauru.pdf: 4611767 bytes, checksum: 71f830e143f447c9e962c2305462a623 (MD5) / Made available in DSpace on 2016-02-17T16:11:21Z (GMT). No. of bitstreams: 1 rossi_d_me_bauru.pdf: 4611767 bytes, checksum: 71f830e143f447c9e962c2305462a623 (MD5) Previous issue date: 2015-12-21 / Este trabalho tem por finalidade a deposição de filmes finos de carbono amorfo hidrogenado (a-C:H) e de filmes finos de carbono amorfo hidrogenado com silício (a-C:H:Si). Analisar a incorporação gradativa de cloro nos filmes, tornando-os clorados (a-C:H:Cl e a-C:H:Si:Cl). As técnicas utilizadas para a deposição dos filmes foram: (i) a deposição à vapor químico assistido por plasma (PECVD) e (ii) implantação iônica por imersão em plasma (PIIID). Os filmes foram produzidos a partir de misturas de vapores de propanol, CH3(CH2)2OH, vapores de tetrametilsilano, Si(CH3)4, vapores de clorofórmio, CHCl3, e argônio, Ar, respectivamente monômero 1, monômero 2, comonômero e gás plasmogênico. O aumento do clorofórmio na alimentação do reator acarretou em mudanças nas estruturas químicas do material depositado e também alterações nas suas características ópticas. Para averiguar as modificações nas propriedades ópticas dos filmes foram calculados o coeficiente de absorção, o índice de refração e o gap óptico com base em espectros de transmitância óptica na região do Ultravioleta, Visível e Infravermelho Próximo, (Uv/Vis/NIR). As modificações nas estruturas químicas dos filmes foram analisadas por espectroscopia de absorção no infravermelho por transformada de Fourier, FTIR, visando revelar os grupos químicos presentes nos filmes. Espectroscopia de fotoelétrons de raios X, (XPS), foi a técnica utilizada para desvendar a composição química elementar dos filmes e a 6concentração dos elementos presentes. As características de molhabilidade dos filmes foram medidas em um goniômetro, através da análise da interação da gota de um fluído com a superfície dos filmes. Espessuras medidas por perfilômetria foram comparadas a valores teóricos provenientes das constantes ópticas. Os resultados do XPS demonstraram a presença de cloro nos filmes, a concentração máxima obtida foi de ~ 8% at. Houve um aumento na taxa de deposição dos filmes em função do aumento da proporção de clorofórmio na entrada do reator. O ângulo de contato apresentou-se em torno de 75° para os filmes aC:H:Cl e em torno de 80° para os filmes a-C:H:Si:Cl. As análises ópticas Uv/Vis/NIR apresentaram índice de refração de ~1.5, calculadas por modelos computacionais iterativos, o gap de Tauc aumentou de 1,9 eV para 2,5 eV para filmes finos a-C:H clorados. / Thin hydrogenated amorphous carbon (a-C:H) and (a-C:H:Si) films were produced and the gradual incorporation of chlorine turn into a-C:H:Cl films and aC:H:Si:Cl films. The a-C:H:Cl and a-C:H:Si:Cl films were produced by plasma enhanced chemical vapor deposition (PECVD) from mixtures of vapor of propane, CH3(CH2)2OH, tetramethylsilane, Si(CH3)4, chloroform, CHCl3, and argon gas, Ar; respectively monomer 1, monomer 2, comonomer and argon gas. The increase of chloroform in the film composition resulted in changes in the chemical structure of the material and also changes in its optical characteristics. To investigate the changes in the optical properties of the films, the absorption coefficient, refractive index and band gap were calculated from optical transmittance spectra in the Ultraviolet, Visible and Near Infrared (Uv/Vis/NIR) regions. The modifications in chemical structures of the films were analyzed by Fourier transform infrared spectroscopy FTIR. X-ray photoelectron spectroscopy (XPS) was the technique used to measure the chemical composition of the films. The wettability characteristics were measured using a goniometer, through the analysis of the interaction of a fluid drop on the surface of the films. Film thicknesses were measured using perfilometry and compared with theoretical values derived from optical data. The XPS results showed chlorine in the film, and the maximum concentration was about 8% at. There was an increase in the deposition rate as 8chloroform proportion reactor inlet was added. The contact angle showed around 75° to a-C:H:Cl films and around 80° to a-C:H:Si:Cl films. The optical analyses Uv/Vis/NIR showed refractive index of ~1.5, calculated for interactive computer models. The Tauc band gap increased from 1,9 eV to 2,5 eV for a-C:H chlorinated films.

Depuis la découverte de la première exoplanète en 1995 par Mayor et Queloz, le nombre de planètes extrasolaires découvertes n'a cessé d'augmenter, pour dépasser les 1000 planètes à la fin de l'année 2013. Depuis le début des années 2000, la détection s'est accompagnée d'une volonté de caractérisation de l'atmosphère des exoplanètes. Les méthodes utilisées jusqu'ici sont la spectroscopie de transit primaire et l'étude des émissions thermiques en transit secondaire ou via l'étude des courbes de phase. L'objet de cette thèse s'inscrit dans cette recherche de caractérisation des atmosphères exoplanétaires, en s'intéressant à une méthode jusqu'ici inexplorée : l'analyse des émissions thermosphériques, i.e. les émissions de la haute atmosphère induites par les entrées énergétiques, flux extrême UV de l'étoile hôte et précipitations électroniques principalement. La première partie de cette thèse s'intéresse aux émissions thermosphériques de la Terre primitive avec une approche basée sur la modélisation. Le but étant la détermination des différentes émissions de la Terre à travers son histoire, afin de disposer de proxies pour la recherche et la caractérisation d'exoplanètes telluriques. Dans un premier temps nous avons calculé l'émission de l'atmosphère primordiale de la Terre irradiée par le Soleil jeune dans la raie Lyman Alpha. Nous avons montré que la raie planétaire, principalement formée par diffusion cohérente, montre un rapport d'émission avec le Soleil de l'ordre de 10-8, inaccessible aux observations, avec les instruments actuels ou de prochaine génération. Ce premier résultat nous à conduit à étudier la faisabilité d'une méthode indirecte de détection d'une couronne dense d'hydrogène autour d'une planète tellurique possédant une atmosphère de CO2 par les émissions des sous-produits de dissociation et d'ionisation de CO2. Les calculs menés sur la raie verte de l'oxygène (état O1S) et le doublet UV de CO2+ (état B2Σu+) ont montré que ces émissions présentaient des contrastes de l'ordre de 10^-12 avec le Soleil dans le cas d'une Terre primitive, et de l'ordre de 10^-6-10^-8 pour une planète tellurique proche d'une naine M. La conclusion générale des ces investigations est que les raies fines (atomiques ou moléculaires) des émissions thermosphériques sont trop faibles pour être détectées par les instruments actuels. Une voie possible serait l'étude des bandes d'émission moléculaires, qui nécessite une meilleure compréhension de la distribution en intensité des différentes bandes à travers le spectre, compréhension qui passe par l'étude expérimentale de ces émissions. C'est dans ce cadre que se situe la deuxième partie de cette thèse, qui s'intéresse à l'analyse spectroscopique de la Planeterrella, simulateur d'aurores boréales initialement développé à des fins pédagogiques. Nous avons réalisé une étude spectroscopique à basse et haute résolution de l'air, afin de caractériser les émissions présentes dans l'expérience d'une part, et aussi de disposer d'un spectre de référence qui servira à terme de test pour un code Monte Carlo développé pour étudier le dispositif expérimental, la caractérisation du dispositif constituant une étape nécessaire pour faire de la Planeterrella un objet d'étude scientifique. Enfin, la spectroscopie basse résolution du CO2 a été réalisée, avec des applications potentielles à Mars. / Since the discovery of the first exoplanet in 1995 by Mayor and Queloz, the number of extrasolar planets discovered has continuously grown up, to overtake 1000 planets at the end of 2013. Since the beginning of the 2000's, came with the detection the will to characterize the atmospheres of these exoplanets. Until now, the methods used are the primary transit spectroscopy and the study of the thermal emissions in secondary transit or using phase curves. The purpose of this thesis belongs to that search for characterizing exoplanetary atmospheres, by looking at a method unexplored until now: the study of the thermospheric emissions, i.e. emissions from the upper atmosphere induced by the energetic entries, mainly the extreme UV flux and the electronic precipitations. The first part of this thesis concerns the thermospheric emissions of the primitive Earth with an approach based on modeling. The goal is the determination of the several emissions of the Earth through its history in order to have proxies for the search and the characterization of telluric exoplanets. Initially we calculated the emission of the primary atmosphere of the early Earth under the young Sun in the Lyman Alpha line. We showed that the planetary line in mainly due to coherent diffusion and that the emission ratio between the planet and the Sun in this line is of about 10-8, far from the capabilities of current or next generation instruments. This first result lead us to study the feasibility of an indirect method to infer the presence of dense hydrogen corona surrounding a telluric planet with a CO2-dominated atmosphere, by studying its influence on the emissions of two CO2 by-products. The calculations carried out on the oxygen green line (O1S state) and the UV doublet of CO2+ (B2Σu+ state) showed that theses emissions present contrasts of about 10^-12 with the young Sun in the case of a primitive Earth, and of about 10^-6-10^-8 for a close-in telluric planet around a M dwarf. The general conclusion of the investigations is that the thermospheric emissions of thin (atomic or molecular) lines are too weak to be detected. A possible way could be the study of the molecular bands, of which emissions need to be better understood, especially concerning the intensity distribution of the several bands through the spectrum. This comprehension implies experimental studies of these emissions. The second part of this thesis lies in this scope and concerns the spectroscopic analysis of the Planeterrella, an aurora borealis simulator initially designed for outreach purpose. We made a spectroscopic study at low and high resolution with air, in order to characterize the emissions existing in the experiment, and also to have a reference spectrum which will be a final test for a Monte Carlo code developed to study the experimental device, the characterization of this device being a necessary step for the Planeterrella to become suitable for scientific purpose. Finally, we made a low resolution spectroscopic study of carbon dioxide, with potential applications to Mars.

Made available in DSpace on 2014-06-11T19:29:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-12-20Bitstream added on 2014-06-13T20:19:01Z : No. of bitstreams: 1 pasqualotto_s_me_araiq.pdf: 3001560 bytes, checksum: 03f70975a62c3defd4e56c0d98704458 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A preocupação com a radiação ultra-violeta (UV) do espectro eletromagnético que atinge a superfície terrestre, devido ao aumento do índice de câncer de pele, tem incentivado a pesquisa de produtos para a proteção da pele. Este trabalho tem como objetivo a obtenção e estudo do filtro inorgânico ZnO:Ti4+ com 1, 5, 10, 20, 40, 50% em mol do dopante e a associação dos filtros dopados obtidos com o filtro orgânico 1-(4-terc-butilfenil)-3-(4- metoxifenil)propano-1,3-diona ou butil metoxi dibenzoil metano (bmdm), comercialmente denominado Eusolex 9020. Os filtros dopados foram obtidos pelo método sol-gel, com razão de hidrólise de 0,1 e de 0,01. As amostras foram caracterizadas por espectroscopia de absorção através de medidas de refletância difusa (RD), espectroscopia na região do infravermelho (IV), espectroscopia na região do ultravioleta – visível (UV-Vís), difratometria de raios X (DRX), colorimetria, medidas de potencial zeta, razão UVA/UVB e comprimento de onda crítico foram calculados para conhecer o desempenho dos filtros na região do UVA. Os resultados de DRX indicam a formação da fase ZnO wurtzita para dopagens de até 10%. Acima dessa porcentagem de “dopante”, observa-se a formação de fases de titanatos de zinco (Zn2TiO4 e ZnTiO3). Os espectros no IV apresentam bandas referentes à ligação metaloxigênio deslocadas para maiores números de onda com o aumento da quantidade de dopante, devido ao efeito da força de ligação e do tamanho do íon de titânio em relação ao de zinco nas interações metal-oxigênio. Os espectros de RD apresentam deslocamento das bandas para a região do visível. Os filtros dopados obtidos foram, então, associados com o filtro orgânico bmdm. Os filtros associados foram caracterizados pelas mesmas técnicas acima descritas. Nos espectros IV dos filtros... / The concern with UV radiation of the electromagnetic spectrum that reaches the earth's surface has encouraged the research of products for skin protection due to increased rates of skin cancer. This study aims to obtain and study the inorganic filter ZnO:Ti4+ with 1, 5, 10, 20, 40, 50 at% of doping and the association with doped filters developed through organic filter 1 - (4-tert- butyl phenyl) -3 - (4-methoxyphenyl) propane-1 ,3-dione or butyl methoxy dibenzoyl methane (bmdm), trade name Eusolex 9020®. Doped filters were obtained by the sol-gel method, with hydrolysis ratio of 0.1 and 0.01. The samples were characterized by absorption spectroscopy using diffuse reflectance (DR), infrared (IR) spectroscopy, ultraviolet - visible (UV-Vis), X-ray diffraction (XRD), colorimetric and zeta potential measurements. UVA/UVB ratio and critical wavelength were calculated to know the filter’s performance in the UVA region. XRD results indicate the ZnO wurtzite phase formation step for doping levels up to 10%. Above this percentage of doping, phases of zinc titanates (Zn2TiO4 and ZnTiO3) we observed. The IR spectra show bands of the metal-oxygen shifted to higher wave numbers and an increasing amount of dopant due to the bond strength and size effects of the titanium ion compared to zinc ion in metaloxygen interactions. The RD spectra show shifts of bands for the visible region. Doped filters were then associated with the bmdm organic filter. The associated filters were characterized by the same techniques just described above. In the IR spectra of the associated filters, there is also the band on the metal-oxygen, splitting and shifting of the band related to the carbonyl group when compared with the free bmdm, that indicates an association between the filters. The absorption bands of doped filters do not cover... (Complete abstract click electronic access below)

Submitted by Leandro William Franco (leandrowffisica@gmail.com) on 2018-04-17T21:41:32Z No. of bitstreams: 1 franco_lw_me_pru.pdf: 4808870 bytes, checksum: 40a212abf7d60d9ba97113c34fc078a0 (MD5) / Approved for entry into archive by Claudia Adriana Spindola null (claudia@fct.unesp.br) on 2018-04-18T12:57:53Z (GMT) No. of bitstreams: 1 franco_lw_me_prud.pdf: 4808870 bytes, checksum: 40a212abf7d60d9ba97113c34fc078a0 (MD5) / Made available in DSpace on 2018-04-18T12:57:53Z (GMT). No. of bitstreams: 1 franco_lw_me_prud.pdf: 4808870 bytes, checksum: 40a212abf7d60d9ba97113c34fc078a0 (MD5) Previous issue date: 2018-03-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Neste trabalho é proposta uma Sequência Didática para alunos do 2º Termo do Ensino Médio da Educação de Jovens e Adultos, abordando os efeitos desencadeados pela radiação ultravioleta (UV) à saúde humana. Na elaboração deste material foram utilizados vários referenciais teóricos: Lev Vygotsky, Antoni Zabala, Emico Okuno, Maria Apparecida Constantino Vilela e o Currículo de Física do Estado de São Paulo. Quanto ao objeto de ensino são abordadas situações cotidianas de excessiva exposição à radiação UV, em especial, à radiação solar. No desenvolvimento das atividades são apresentadas algumas fotografias e um questionário investigativo, além de vídeos, leituras de textos de divulgação científica, leitura e interpretação de gráficos representativos do índice UV e uma atividade experimental. Ressaltase que a produção deste trabalho valeu-se de uma pesquisa qualitativa e de natureza descritiva. Destaca-se também que o produto educacional pode ser utilizado num trabalho interdisciplinar no ensino de Física, Química e Biologia. Assim sendo, espera-se que a aplicação dessa Sequência Didática propicie aos estudantes a aquisição de novos conhecimentos, para assim, assumirem nova postura sobre os cuidados e medidas preventivas que possibilite a eles a ruptura de certas concepções em relação às situações de exposição à radiação UV. / This paper proposes a Didactic Sequence for students of the 2nd Term of Secondary Education of Young and Adult Education, addressing the effects of ultraviolet (UV) radiation on human health. In the elaboration of this material several theoretical references were used: Lev Vygotsky, Antoni Zabala, Emico Okuno, Maria Apparecida Constantino Vilela and the Curriculum of Physics of the State of São Paulo. Regarding the teaching object, daily situations of excessive exposure to UV radiation, especially solar radiation, are addressed. In the development of the activities are presented some photographs and an investigative questionnaire, as well as videos, readings of scientific dissemination texts, reading and interpretation of graphs representative of the UV index and an experimental activity. It is emphasized that the production of this work was based on a qualitative and descriptive research. It is also emphasized that the educational product can be used in an interdisciplinary work in the teaching of Physics, Chemistry and Biology. Therefore, it is expected that the application of this Didactic Sequence will allow the students to acquire new knowledge to take a new stance on the precautions and preventive measures that allow them to break certain concepts regarding the situations of exposure to radiation UV.