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Detecção da doença "mela-das-sementes da braquiária" em gramíneas forrageiras através de técnicas de sensoriamento remoto /Rosatti, José Carlos. January 2006 (has links)
Orientador: Erivaldo Antonio da Silva / Banca: Hélio Ricardo Silva / Banca: Rubens Augusto Camargo Lamparelli / Resumo: Imagens CCD/CBERS 2 nas bandas B2, B3 e B4, dos anos de 2004 e 2005, de Mirante do Paranapanema, SP (Brasil), foram transformadas em reflectância de superfície usando o modelo 5S de correção atmosférica e normalizadas radiometricamente tendo como base o trabalho desenvolvido por Hall et al. (1991). O objetivo foi caracterizar espectralmente áreas de pastagens de Brachiaria brizantha (Hoschst ex A. Rich) Stapt, em fase de florescimento, isentas e infectadas com a doença "mela-das-sementes da braquiária", no sentido de possibilitar a sua detecção através da comparação entre os valores de FRBS - Fator de Reflectância Bidirecional de Superfície. Ao mesmo tempo, objetivou-se também, avaliar a eficácia das imagens CCD/CBERS-2 para a obtenção de respostas espectrais de pastagens. Os valores de reflectância de superfície foram comparados e analisados através da variação espectral existente entre as áreas sadias e doentes e os resultados indicaram que as principais diferenças foram a diminuição da reflectância na banda B3 e o aumento da reflectância na banda B4 nas áreas doentes. Diferenças significativas também foram constatadas pela comparação entre dados obtidos de imagens índices de vegetação NDVI e RVI. A metodologia empregada com o uso de imagens CCD/CBERS-2 mostrou-se eficaz para descriminar áreas infectadas com a doença. / Abstract: CCD/CBERS 2 images in the spectral bands B2, B3 and B4 of the years 2004 and 2005, from Mirante do Paranapanema, SP (Brazil), were transformed in surface reflectance images using the model 5S of atmospheric correction and radiometrically normalized tends as base the work developed by Hall et al. (1991). The objective was characterize spectrally areas of pastures of Brachiaria brizantha (Hoschst ex A. Rich) Stapt, in your flowering phase, exempt and infected with the disease "mela-das-sementes da braquiária", in the sense of making possible your detection through the comparison among the FRBS - Surface of Bidirectional Reflectance Factor values. At the same time, it was aimed at to evaluate the effectiveness of the CCD/CBERS-2 images for the obtaining of spectral response of pastures. The surface of reflectance values were compared and analyzed through the existent spectral variation between the healthy and diseased areas and the results they indicated that the main differences were the decrease of the reflectance in the band B3 and the increase of the reflectance in the band B4 in the diseased areas. Significant differences were also verified by the comparison among obtained of vegetation indexes NDVI and RVI data. The methodology used with the use of CCD/CBERS-2 images it was shown effective for discrimination the areas infected with the disease. / Mestre
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Spectroscopic and Kinetic Characterization of Photochromic Ruthenium Chelating Sulfoxide ComplexesMcClure, Beth Anne January 2010 (has links)
No description available.
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Detecção da doença mela-das-sementes da braquiária em gramíneas forrageiras através de técnicas de sensoriamento remotoRosatti, José Carlos [UNESP] 23 February 2006 (has links) (PDF)
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rosatti_jc_me_prud.pdf: 4413126 bytes, checksum: 5ac8f38c862833923e7eac17a3667cba (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Imagens CCD/CBERS 2 nas bandas B2, B3 e B4, dos anos de 2004 e 2005, de Mirante do Paranapanema, SP (Brasil), foram transformadas em reflectância de superfície usando o modelo 5S de correção atmosférica e normalizadas radiometricamente tendo como base o trabalho desenvolvido por Hall et al. (1991). O objetivo foi caracterizar espectralmente áreas de pastagens de Brachiaria brizantha (Hoschst ex A. Rich) Stapt, em fase de florescimento, isentas e infectadas com a doença mela-das-sementes da braquiária, no sentido de possibilitar a sua detecção através da comparação entre os valores de FRBS - Fator de Reflectância Bidirecional de Superfície. Ao mesmo tempo, objetivou-se também, avaliar a eficácia das imagens CCD/CBERS-2 para a obtenção de respostas espectrais de pastagens. Os valores de reflectância de superfície foram comparados e analisados através da variação espectral existente entre as áreas sadias e doentes e os resultados indicaram que as principais diferenças foram a diminuição da reflectância na banda B3 e o aumento da reflectância na banda B4 nas áreas doentes. Diferenças significativas também foram constatadas pela comparação entre dados obtidos de imagens índices de vegetação NDVI e RVI. A metodologia empregada com o uso de imagens CCD/CBERS-2 mostrou-se eficaz para descriminar áreas infectadas com a doença. / CCD/CBERS 2 images in the spectral bands B2, B3 and B4 of the years 2004 and 2005, from Mirante do Paranapanema, SP (Brazil), were transformed in surface reflectance images using the model 5S of atmospheric correction and radiometrically normalized tends as base the work developed by Hall et al. (1991). The objective was characterize spectrally areas of pastures of Brachiaria brizantha (Hoschst ex A. Rich) Stapt, in your flowering phase, exempt and infected with the disease mela-das-sementes da braquiária, in the sense of making possible your detection through the comparison among the FRBS - Surface of Bidirectional Reflectance Factor values. At the same time, it was aimed at to evaluate the effectiveness of the CCD/CBERS-2 images for the obtaining of spectral response of pastures. The surface of reflectance values were compared and analyzed through the existent spectral variation between the healthy and diseased areas and the results they indicated that the main differences were the decrease of the reflectance in the band B3 and the increase of the reflectance in the band B4 in the diseased areas. Significant differences were also verified by the comparison among obtained of vegetation indexes NDVI and RVI data. The methodology used with the use of CCD/CBERS-2 images it was shown effective for discrimination the areas infected with the disease.
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Caracterização espectral de espécies de Mata Atlântica de Interior em nível foliar e de copa / Spectral characterization of species from Mata Atlântica de Interior in canopy and leaf levelMiyoshi, Gabriela Takahashi [UNESP] 29 February 2016 (has links)
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Previous issue date: 2016-02-29 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Florestas têm importante papel na manutenção da biodiversidade, retenção de carbono e regulação do regime hidrológico, além de garantir proteção ao solo e às fontes d’água. Podem ser classificadas em diferentes estádios de desenvolvimento, caracterizados pela presença de espécies secundárias e clímax. Atualmente, no Brasil, as florestas estão reduzidas em fragmentos espalhados em diversas regiões do país sendo seu monitoramento necessário para realização de planos de manejo. Uma das formas de realizar o monitoramento florestal é utilizando o Sensoriamento Remoto hiperespectral, que fornece informação espectral detalhada dos alvos as quais são úteis para a discriminação das espécies de vegetação que compõem o remanescente florestal. Sensores hiperespectrais acoplados a VANTs (Veículos Aéreos Não Tripulados) possibilitam a aquisição de dados para posterior delimitação das copas das espécies de vegetação. A Mata Atlântica, bioma rico em biodiversidade, está distribuída de norte a sul do Brasil, sendo classificada conforme a localização e características de cada formação florestal, dentre elas a Mata Atlântica de Interior. O objetivo desse trabalho é a caracterização espectral de espécies de vegetação em nível foliar e de copa para contribuir com informações que possam ser utilizadas para o monitoramento florestal. Foram adquiridas imagens hiperespectrais com câmara baseada no Interferômetro de Fabry-Perot acoplada em VANT. As imagens foram adquiridas na gleba Ponte Branca, pertencente à Estação Ecológica Mico-Leão-Preto. O processamento das imagens considerou 5 diferentes correções que permitiram mostrar a importância da geometria de aquisição das imagens e do ajustamento radiométrico em bloco. Copas de 12 espécies de vegetação foram delimitadas manualmente no mosaico de imagens gerado e nelas foram medidos valores de Fator de Reflectância Hemisférico Cônico. A caracterização espectral em nível foliar de 16 espécies de vegetação foi realizada em laboratório utilizando espectrorradiômetro. Por meio da análise de agrupamento, verificou-se a similaridade entre as respostas espectrais de tais espécies, tanto em nível de copa como foliar. Para minimizar a similaridade entre tais respostas, foram aplicados e normalizados 7 índices de vegetação. Por fim, utilizando os índices que apresentaram menor correlação entre si, uma nova análise de agrupamento foi realizada onde se verificou que a similaridade entre as espécies foi atenuada. / Forests have an important role to support biodiversity, carbon stocks and water regime. In addition, provide fundamental protection to soil and water resources. Pioneers and climax species characterize successional stages of forest. In Brazil, forests are reduced to fragments spread out over the country, being their monitoring necessary to perform management plans. Hyperspectral Remote Sensing provides detailed spectral information about targets and is feasible to discriminate trees species. Hyperspectral sensor attached to UAVs (Unmanned Aerial Vehicles) makes possible the delineation of trees canopies. The Atlantic Forest, biome rich in biodiversity, is distributed from north to south in Brazil, being classified according to the different locations and characteristics, such as the Interior Atlantic Forest. The main objective of this project is spectral characterization of tree species in leaf and canopy level to contribute with forest monitoring. Hyperspectral images acquired with camera based on Fabry-Perot Interferometer coupled to an UAV were acquired. The interest area, Ponte Branca, belongs to the ecological station called Estação Ecológica Mico-Leão-Preto in the western region of São Paulo State. Imaging process where realized with 5 different corrections showing the importance of geometry during image acquisition and radiometric block adjustment. Trees canopies from 12 species were manually delimited in the images mosaic and Hemispherical Conical Reflectance Factor were obtained. Leaf spectral characterization was realized in laboratory using spectrorradiometer. Clustering analyses were applied to verify similarity between spectral responses of species, in canopy and leaf level. 7 vegetation indexes were applied and normalized in order to reduce the similarity between the spectral responses. Lastly, a new clustering analyses was realized using the less correlated normalized indexes, concluding that the similarity between species was reduced. / CNPq: 130871/2014-1
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Vers les lasers XUV femtosecondes : étude des propriétés spectrales et temporelles de l'amplification de rayonnement XUV dans un plasma / Toward X-ray lasers : study of the spectral and temporal properties of X-ray radiation amplification in a plasmaLe Marec, Andréa 19 October 2016 (has links)
Cette thèse s’inscrit dans le contexte des travaux visant à réduire la durée d’impulsion des lasers XUV générés dans des plasmas au domaine femtoseconde. La bande spectrale très étroite du milieu amplificateur limite la durée minimum accessible (limite de Fourier). Le milieu amplificateur des lasers XUV sont des plasmas denses et chauds qui peuvent être créés aussi bien par décharge électrique rapide que par différents types de lasers de puissance. Il existe ainsi 4 types de sources lasers XUV distinctes dont les paramètres du plasma (densité, température) dans la zone de gain diffèrent. Or, les propriétés spectrales et temporelles du rayonnement émis sont fortement liées à ces paramètres. L’ensemble des 4 types de lasers XUV opèrent en mode d'amplification de l'émission spontanée (ASE) et 2 d'entre eux peuvent opérer en mode « injecté ». Cette technique consiste à injecter une impulsion harmonique d'ordre élevé femtoseconde, résonante avec la transition laser, à l'une des extrémités du plasma amplificateur. L'important désaccord entre la largeur spectrale du plasma et celle de l'harmonique ne permet pas de conserver la durée fs de cette dernière au cours de l'amplification. Les simulations (code Bloch-Maxwell COLAX) montrent que l'amplification est fortement non-linéaire dans ces systèmes, avec notamment l'apparition d’oscillations de Rabi. La génération d'oscillations de Rabi dans des lasers XUV en mode injecté est actuellement considérée comme un moyen prometteur de produire des lasers XUV fs, mais la manifestation de ces dernières n’a toutefois encore jamais été mise en évidence expérimentalement. Ainsi, une méticuleuse caractérisation expérimentale des propriétés spectrales des 4 types de lasers XUV en relation avec les conditions du plasma, associée à une meilleure compréhension des mécanismes d’amplification sous différentes conditions plasma basée sur des études théoriques et des simulations, sont nécessaires pour atteindre notre objectif. Une large campagne expérimentale visant à caractériser spectralement l'ensemble des différents types de lasers XUV a été menée par notre groupe sur la dernière décennie. La résolution spectrale nécessaire n'étant pas accessible avec les spectromètres actuels, la méthode employée consiste à mesurer la cohérence temporelle du laser XUV par autocorrélation du champ électrique à l'aide d'un interféromètre à division de front d'onde, spécifiquement conçu pour ces mesures, à partir desquelles la largeur spectrale peut être déduite. Le dernier type de laser XUV (PALS, Prague) a été caractérisé dans le cadre de cette thèse. Le temps de cohérence mesuré est de 0,68 ps, significativement inférieur aux valeurs mesurées sur les autres types de lasers XUV. L'analyse de l'ensemble des mesures a fait apparaître un comportement différent suivant que la durée d’impulsion est longue devant le temps de cohérence ou proche de celui-ci. Dans le premier cas les largeurs spectrales déduites sont en bon accord avec les calculs, dans le second l’accord est moins bon et la forme des traces d'autocorrélation n'était pas comprise. Ces observations ont motivé une étude détaillée de l'influence des propriétés temporelles de l'émission ASE des lasers XUV sur la méthode interférométrique employée pour caractériser leur largeur spectrale. Cette étude, basée sur un modèle emprunté aux lasers à électrons libres, a révélé un effet de la cohérence temporelle partielle sur les mesures d'autocorrélation en champ de ces sources. Elle ouvre des perspectives sur l'utilisation de notre méthode pour une mesure simultanée de la largeur spectrale et de la durée d'impulsion de la source. Enfin, une étude basée sur un modèle Bloch-Maxwell a été réalisée pour tenter de mieux comprendre les conditions d'apparition des oscillations de Rabi au cours de l'amplification de l'harmonique dans le plasma de laser XUV. Deux régimes d'amplification, adiabatique et dynamique, autour d'un seuil d'inversion de population ont été mis en évidence. / The work of this thesis was made in the context of the efforts made to reduce the pulse duration of plasma-based XUV lasers down to the femtosecond domain. The very narrow spectral width of the amplifier medium (~ 1E10 - 1E11 Hz) limits the minimum achievable pulse duration (Fourier limit). The amplifier medium of XUV lasers pumped by collisional excitation are dense and hot plasmas that can be created both by rapid electrical discharge and by different types of power lasers. There are thus 4 distinct types of XUV laser sources with different plasma parameters (density, temperature) in the gain region. Yet, the spectral and temporal properties of the emitted radiation are strongly linked to these parameters. All 4types of XUV lasers operate in amplification of spontaneous emission (ASE) mode, and 2 of them, for a few years, can operate in "seeded" mode. This technique consists in injecting a femtosecond high order harmonic pulse (the seed), resonant with the lasing transition, at one extremity of the plasma amplifier. Because of the major mismatch between the spectral width of the plasma and that of the seed the femtosecond duration of the latter is not preserved during amplification. Simulations (COLAX Maxwell-Bloch code) show that the amplification is highly non-linear in such systems, including the appearance of Rabi oscillations. Generating Rabi oscillations in seeded XUV lasers is currently considered a promising way to produce femtosecond XUV lasers. However Rabi oscillations have yet never been experimentally demonstrated. Thus, a meticulous experimental characterization of the spectral properties of the 4 types of XUV lasers in connection with the plasma conditions, combined with a better understanding of amplification mechanisms under different theoretical plasma conditions based on studies and simulations are needed to reach our goal. A wide experimental campaign aiming to spectrally characterize all different types of XUV lasers was conducted by our group over the past decade. The required spectral resolution is not available with the best current spectrometers, so the method we used consists on the measurement of the temporal coherence of the XUV laser through an electric field autocorrelation, using a wave front-division interferometer that was specifically designed for these measures, from which the spectral width can be deduced. The latter type of the four XUV laser types (PALS, Prague) was characterized during this thesis, closing this experimental campaign. The measured coherence time was 0.68 ps, which is significantly lower than the coherence times measured on the other XUV laser types. Analysis of the overall results revealed two different behavior whether the XUV laser has a long pulse duration compared to its coherence time or if the two durations are close. In the first case the inferred spectral widths are in good agreement with theoretical predictions, while in the second case the agreement was not as good and the shape of the electric field autocorrelation traces was not understood. This observation has prompted a detailed study of the influence of temporal properties of ASE XUV lasers on the interferometric methodology used to determine the spectral width of XUV lasers. The study, based on a model developed for X-free electron lasers, revealed an effect of partial temporal coherence in electric field autocorrelation measures of these sources. This study offers perspectives on a simultaneous measure of the spectral width and the duration of theses sources with our method. Finally, a study based on Maxwell-Bloch equations was carried out in order to understand better the conditions of apparition of Rabi oscillations. This study highlighted two amplification regimes, adiabatic and dynamic, around a population inversion threshold.
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Comportamento higroscópico do suco de laranja liofilizado / Higroscopic behavior of freeze-dried orange juicePitombo, Ronaldo Nogueira de Moraes 30 March 1990 (has links)
0 comportamento higroscópico do suco de laranja liofilizado, e aditivado com malto-dextrinas e lactose, e de misturas mecânicas do suco liofilizado com os aditivos secos, foi estudado através da cinética e das isotermas de sorção de água, em diferentes temperaturas. Avaliou-se as características espectrais no visível e ultravioleta, e o teor de vitamina C, de amostras de suco de laranja liofilizado expostas a diferentes umidades relativas e temperaturas. Estudou-se a influência do valor de pH e natureza do tampão sobre a retenção do limoneno emulsionado em soluções de lactose, liofilizadas. A liofilização praticamente não alterou o teor de vitamina C e as características espectrais do suco de laranja, mas aumentou o valor monomolecular da malto-dextrina (dextrose equivalente de 9 a 12%). A lactose liofilizada apresentou-se no estado amorfo. Os teores de umidade de equilíbrio das misturas aditivadas liofilizadas, foram menores que os das misturas mecânicas. Os aditivos reduziram a sorção de umidade em função do tempo. A retenção do limoneno foi influenciada pela sua concentração inicial, sendo que ocorreu a major perda, durante a liofilização na major concentração utilizada. / The higroscopic behavior of freeze-dried orange juice, with added maltodextrins and lactose and mechanical mixtures with this additives was studied through the kinetics and isoterms of water sorption in different temperatures. It was evaluated the spectral characteristics, in the visible and ultraviolet range, and the vitamin C content from samples of freeze-dried orange juice exposed at different relative humidities and temperatures. It was studied the influence of pH and buffer composition, on the limonene retention of freeze-dried emulsions. The spectral characteristics and vitamin C content showed no alterations after liofilization the maltodextrin (9-12 % dextrose equivalent monomolecular value increased. Freezedried lactose was amorphous. The equilibrium humidity content of the samples with additives were reduced when compared with mechanical mixtures. The additives also reduced the rate of water sorption. The limonene retention during freeze-drying was influenced by the initial concentration of the emulsion. The greater concentration studied showed the lower retention value.
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Comportamento higroscópico do suco de laranja liofilizado / Higroscopic behavior of freeze-dried orange juiceRonaldo Nogueira de Moraes Pitombo 30 March 1990 (has links)
0 comportamento higroscópico do suco de laranja liofilizado, e aditivado com malto-dextrinas e lactose, e de misturas mecânicas do suco liofilizado com os aditivos secos, foi estudado através da cinética e das isotermas de sorção de água, em diferentes temperaturas. Avaliou-se as características espectrais no visível e ultravioleta, e o teor de vitamina C, de amostras de suco de laranja liofilizado expostas a diferentes umidades relativas e temperaturas. Estudou-se a influência do valor de pH e natureza do tampão sobre a retenção do limoneno emulsionado em soluções de lactose, liofilizadas. A liofilização praticamente não alterou o teor de vitamina C e as características espectrais do suco de laranja, mas aumentou o valor monomolecular da malto-dextrina (dextrose equivalente de 9 a 12%). A lactose liofilizada apresentou-se no estado amorfo. Os teores de umidade de equilíbrio das misturas aditivadas liofilizadas, foram menores que os das misturas mecânicas. Os aditivos reduziram a sorção de umidade em função do tempo. A retenção do limoneno foi influenciada pela sua concentração inicial, sendo que ocorreu a major perda, durante a liofilização na major concentração utilizada. / The higroscopic behavior of freeze-dried orange juice, with added maltodextrins and lactose and mechanical mixtures with this additives was studied through the kinetics and isoterms of water sorption in different temperatures. It was evaluated the spectral characteristics, in the visible and ultraviolet range, and the vitamin C content from samples of freeze-dried orange juice exposed at different relative humidities and temperatures. It was studied the influence of pH and buffer composition, on the limonene retention of freeze-dried emulsions. The spectral characteristics and vitamin C content showed no alterations after liofilization the maltodextrin (9-12 % dextrose equivalent monomolecular value increased. Freezedried lactose was amorphous. The equilibrium humidity content of the samples with additives were reduced when compared with mechanical mixtures. The additives also reduced the rate of water sorption. The limonene retention during freeze-drying was influenced by the initial concentration of the emulsion. The greater concentration studied showed the lower retention value.
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Nouveaux concepts de filtres spectraux ultra-sélectifs pour spectroscopie embarquée / New ultra-narrow band optical filters for embedded spectroscopySharshavina, Ksenia 06 December 2016 (has links)
Les filtres spectraux à réseaux résonants, ou GMRF (Guided-Mode Resonance Filters), sont une nouvelle génération de filtres à bande étroite et constituent une alternative très prometteuse aux filtres conventionnels multicouches Fabry-Pérot. Le pic de résonance d'un GMRF peut être très fin spectralement et de longueur d'onde de centrage accordable en fonction de l'angle d'incidence. Ces propriétés sont particulièrement importantes pour la spectroscopie. Les travaux antérieurs ont permis de mettre en œuvre une structure originale comportant deux réseaux 1D croisés. Les performances de ce filtre surpassent celles des filtres conventionnels par leur réponse spectrale subnanométrique, leur accordabilité, et leur capacité à s'affranchir de l'influence de la polarisation de l'onde incidente sous incidence oblique. Le but de ce travail est d'explorer les performances ultimes de ce type de dispositif en termes de résolution et taux de réjection, par une approche mêlant théorie, technologie et caractérisation. Nous présentons des résultats expérimentaux d'un filtre en réflexion indépendant de la polarisation, accordable sur 40 nm avec 8.3nm/° d'accordabilité, ayant une réflexion de 10-3 sur une plage de 90nm en dehors de la résonance et un facteur de qualité supérieur à 5000. / Guided Mode Resonance Filters ( GMRF ) are a new generation of narrowband optical filters and are a very promising alternative to conventional multilayer Fabry-Perot filters. The resonance peak of GMRF can be spectrally extremely thin and with a centering wavelength tunable according to the angle of incidence of the light. These properties are particularly important for spectroscopy. Previous works have helped to implement an original structure with two 1D crossed gratings. The performance of this filter overpasses those of conventional filters in their spectral subnanometric response, tunability and their ability to overcome the influence of the polarization of the incident wave under oblique incidence. The aim of this work is to explore the final performances of such devices in terms of resolution and rejection rate, thanks to an approach combining theory, fabrication technology and characterization. We present experimental results of a polarization independent reflective filter, tunable over 40nm with a tunability of 8.3nm / °, having a reflection of 10-3 on a 90nm range outside the resonance and a quality factor over 5000.
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