Les performances de filtration des filtres de CTA vis-à-vis de particules et d’aérosols microbiens (AM) ont été étudiées ainsi quel’influence des conditions opératoires sur le comportement de microorganismes collectés sur les filtres. A l’échelle du laboratoire, une mini CTA ayant deux étages de filtration en série a été développée et validée pour l’étude de filtres prototypes ayant des géométries industrielles. Trois types de filtres de différentes efficacités ont été considérés : G4, F7 et F9 selon la norme EN 779. Deux configurations de filtres ont été étudiées : 1) G4 plan plissé/F7 à poches et 2) F7/F9 à poches. Les filtres ont été colmatés séquentiellement par des particules d’alumine, qui assurent une fraction minérale, puis du riz microniséqui apporte le champignon Penicillium chrysogenum et assure une fraction organique agissant comme substrat pour les microorganismes. Enfin, un AM composé d’endospores de Bacillus subtilis et de spores d’Aspergillus niger a été nébulisé pour la contamination des filtres. Après colmatage, des périodes de marche/arrêt de la ventilation de différentes durées (10 j ou 6 semaines) ont été simulées. Lors des reprises de la ventilation, des comptages de particules et d’AM en avaldes filtres ont été effectués. Les principaux résultats sont : (i) les filtres placés en 2ème étage présentent un colmatage plus faible que ceux du 1er étage de filtration, (ii) survie de B. subtilis, croissance de P. chrysogenum et décroissance d’A. niger sur les filtres quelle que soit la période d’arrêt de ventilation étudiée, et (iii) lors des reprises de ventilation, il n’a pas été observé de relargage d’AM pour la fraction échantillonnée.D’autre part, deux CTA à pleine échelle ont été étudiées pendant 6 mois. Une CTA ayant deux étages de filtration avec une configuration G4 plan plissé/F7 à poches, traite l’air extérieur et le souffle vers des locaux desservis. L’autre CTA correspond à l’extraction de l’air vicié d’un local pour le rejeter vers l’extérieur. La perte de charge des filtres, l’humidité relative, et la température de l’air ont été suivies en continu. L’efficacité des filtres vis-à-vis des particules et des aérosols microbiens a été mesurée une fois par mois. Une méthodologie originale de suivi mensuel de la concentration des microorganismescollectés sur les filtres a été mise en oeuvre. Les principaux résultats sont : (i) faible évolution de la perte de charge du filtre placé en 2ème étage, (ii) efficacité des filtres G4 comparable à celle des filtres G4 prototypes, (iii) efficacité du filtre F7 plus faible que celle des filtres prototypes, ce qui peut être expliqué par une différence de vitesse de filtration entre les deux échelles, (iv) le filtre G4 de la CTA-extraction contient une concentration de microorganismes 10 fois plus élevée que celle du filtre G4 de la CTA-soufflage après 6 mois de fonctionnement. / Filtration performances of Air Handling Units (AHU) filters regarding particles and microbial aerosols have been studied, as well as the influence of the AHU operational conditions on behavior of microorganisms collected on the filters. A lab-scale AHU with two successive filtration stages was developed and validated for the study of prototype filters with industrial geometries. Three types of filters of different efficiency have been considered : G4, F7 and F9 according to EN 779 Standard. Two configurations of filters were considered: 1) G4 pleated/F7 bag and 2) F7/F9 bag. Filters were sequentially clogged by alumina particles which assured a mineral fraction, and then by micronized rice particles which provides the fungi Penicillium chrysogenum and assures an organic fraction which acts as a substrate for microorganisms. Finally, a microbial aerosol composed by endospores of Bacillus subtilis and spores of Aspergillus niger was nebulized for filters contamination. After clogging, stops and restarts of ventilation were simulated for different durations (10 days or 6 weeks). During restarts of ventilation, particles and microbial aerosols samplings were performed downstream of the filters. Main results are: (i) level of clogging is significantly less important for the 2nd filtration stage than for the first one, (ii) survival of B. Subtilis, growth of P. Chrysogenum and decline of A.niger on the filters whatever the period of time studied, and (iii) during restarts of ventilation, microbial aerosols releasing was not detected for sampled fraction. Moreover, two full-scale AHU were studied during 6 months. One of the AHU studied is equipped with two filters in series: a G4 pleated filter in 1st stage and a F7 bag filter in 2nd stage. This AHU treats the outdoor air to blow it towards the indoor environments. The other one extracts the indoor air to reject it back outdoors. The filters pressure drop, relative humidity and temperature of the air were measured continuously. Filters efficiency regarding particles and microbial aerosols were measured once a month. An original methodology for the monthly estimation of the concentration of microorganisms on the filters was implemented. Main results are: (i) no significant evolution of the filter pressure drop in 2nd stage, (ii) efficiency of G4 filters are comparable to the prototype filtersone, (iii) efficiency of F7 filters are lower than prototype filters one, which can be explained by differences of filtration velocity between the two scales, (iv) after 6 months of operation, concentration of microorganisms on G4 filter of the AHU of extraction is 10 times higher than the G4 filter one of AHU who treats outdoor air.

Orientador: Arnaldo Alves Cardoso / Coorientador: Maria Angélica Martins Costa / Banca: Andrew George Allen / Banca: Maria Lúcia Arruda de Moura Campos / Resumo: Este estudo foi desenvolvido com o objetivo de avaliar possíveis impactos de fontes antropogênicas na composição da atmosfera no litoral norte do estado de São Paulo, município de Caraguatatuba. Desde a primeira década do século XXI, este local sofre forte impacto de mudanças nas atividades econômicas impulsionadas pelo projeto de extração de óleo e gás contidos em reservas do pré-sal, pois a região é um dos polos de recebimento e distribuição de petróleo e derivados. Espera-se que o continuo aumento das instalações industriais, trânsito de veículos e embarcações e expansão da área urbana tenham continuidade ainda por muitos anos. Apesar dos possíveis efeitos que essas mudanças podem causar no ambiente não existe nenhum dado sobre composição da atmosfera local e este trabalho apresenta as primeiras medidas de gases ácidos e aerossol atmosférico. As amostragens foram feitas próximo aos limites da área urbana e, de forma concomitante, no alto da Serra do Mar e com isso buscou-se reconhecer possíveis alterações na composição química de gases e aerossol durante os processos de circulação de ar que usualmente ocorrem entre o continente e o oceano e que são influenciados também pelas emissões locais e reações fotoquímicas. Para avaliá-los foi feita caracterização química da atmosfera em relação aos componentes iônicos solúveis do aerossol, aos gases ácidos na fase gasosa e à amônia. Os aerossóis foram coletados por amostrador Hi-Vol, para distribuição do material particulado em sei... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study was developed with the objective of evaluating the possible impacts of anthropic sources on the composition of the atmosphere of a littoral region (Caraguatatuba) located in the state of São Paulo (Brazil). This coastal region is under heavy impact from emissions of various compounds into the atmosphere. The site was chosen as a receiving center for oil and gas extraction products from deepwater reserves known as "pre-sal". The continued growth of industrial facilities, increased traffic of vehicles and ships, along with expansion of the urban area is expected to increase in the coming years. Despite the possible effects on the environment, there is no data on the composition of the local atmosphere. This work presents the first measurements made in the atmosphere of acid gases and aerosol. The samplings were made close to the urban limits of the city and concomitantly at a sampling point located high in the mountains. Possible changes in the chemical composition of gases and aerosols during air circulation processes, which usually occur between the continent and the ocean, have been studied. These processes are mainly influenced by local emissions, photochemical reactions and air circulation. Samples of formic acid, acetic acid, sulfur dioxide, hydrogen chloride and nitric acid were collected using sequential filtration with cellulose filters treated with sodium carbonate. Ammonia was collected with cellulose filter impregnated with oxalic acid. Samples of particu... (Complete abstract click electronic access below) / Mestre

D'abord développées pour traiter les maladies respiratoires (asthme, BPCO...), les thérapies inhalées sont depuis peu l'objet d'un intérêt particulier pour délivrer des molécules dans le sang via la barrière alvéolo-capillaire. Quelle que soit la cible de ces thérapies, leur efficacité dépend de la quantité de médicament qui arrive sur la zone à traiter dans l'arbre respiratoire. La région extrathoracique (appelée "région ET" et comprenant la bouche, l'oropharynx, le larynx et le début de la trachée) se comporte alors comme un "filtre" où se dépose une certaine masse de médicament. Afin d'optimiser une telle administration, il est nécessaire de connaître au mieux l'influence des facteurs caractéristiques de l'inhalation (entre autres, le débit d'inhalation, les diamètres des particules inhalées, les propriétés physiques du gaz porteur). Pour cela, un modèle réaliste de région ET a été construit à partir des données issues de l'imagerie médicale. Après la définition d'un maillage et le choix d'un modèle de turbulence et de paramètres adéquats, les équations de Navier-Stokes ont été résolues numériquement pour (i) décrire l'écoulement dans ce modèle et (ii) pour déterminer les trajectoires des particules inhalées. En parallèle, deux études expérimentales ont été menées sur l'exacte reproduction physique du modèle : l'une pour estimer les pertes de pression provoquées par des écoulements d'air et d'oxhel (mélange hélium (78 %) - oxygène (22 %)), l'autre pour mesurer les vitesses par IRM d'un écoulement d'hélium-3 hyperpolarisé. Les résultats obtenus en terme d'écoulement et de quantité de particules déposées dans la région ET sont en accord avec les rares données expérimentales existantes. Ils montrent l'influence prépondérante de la géométrie tant sur l'écoulement (marqué par la présence, vérifiée expérimentalement, du jet laryngeal) que sur le dépôt. Les zones préférentielles de dépôt se situent là où des variations géométriques brusques surviennent (rétrécissement de section et courbures près de l'épiglotte et en amont de la glotte), et là où le caractère turbulent de l'écoulement est prononcé (en fin de larynx notamment). Ces constatations ont permis de caractériser avec précision le dépôt à l'aide de deux nombres adimensionnés : le nombre de Stokes, caractéristique de l'impaction inertielle et le nombre de Reynolds, caractéristique du régime de l'écoulement. L'étude a permis une meilleure appréhension des influences des divers paramètres à considérer pour modéliser une inhalation d'aérosol médicament et, de surcroît, une prévision des quantités de médicament déposée et transmise à l'arbre respiratoire, soit un outil précieux pour l'optimisation des thérapies inhalées. La méthodologie, ainsi développée, est applicable aux morphologies issues d'une étude clinique en cours et permettra d'affiner la caractérisation / Inhaled therapies were originally developed to treat respiratory diseases (e.g., asthma and COPD). They are now the subject of research to deliver medicine to the blood through the alveolar-capillary barrier. The efficacy of such therapies lies in the quantity of medicine that reaches the targeted area in the respiratoy tree. The extrathoracic region (called "ET" and including the mouth, the oropharynx, the larynx and the beginning of the trachea) has the role of a "filter" limiting the amount of medicine that is deposited in the targeted area. In order to optimize the administration of aerosol medicine, it is necessary to know the influence of the various parameters of an inhalation (among others, the inhalation flow rate, the diameter of inhaled particles, the physical properties of the cariier gas). Therefore, a realistic model of the ET region has been constructed from data obtained from medical imaging. The Navier-Stokes equations were numerically solved (i) to describe the flow in the model and (ii) to determine the trajectories of inhaled particles. The numerical analysis required the development of an appropriate mesh and the choice of turbulence model and parameters. In parallel, two experimental studies were performed on an exact physical reproduction of the model : one to estimate the pressure losses in air and oxhel (a helium (78 %) - oxygen (22 %) mixture) flows and another to measure the velocity field using a MRI of a hyperpolarized helium-3 flow. The flow and deposition results that were obtained in the model of the ET region are in agreement with the few existing experimental data. They show the dominant effect of the geometry not only on the flow (marked by the experimentally verified presence of the laryngeal jet) but also on the particle deposition. The major areas of deposition are located where sudden geometrical changes are observed (like the constrictions and the bends near the epiglottis and upstream the glottis) and where the turbulent character of the flow is pronounced (particulary at the end of the larynx). These observations allowed for the accurate characterization of the deposition with non-dimensional numbers : the Stokes number, characteristic number of the inertial impaction, and the Reynolds number, characteristic number of the flow regime. The study allows for the improved comprehension of the influences of the various parameters that must be considered to model the inhalation of aerosol medicine. Furthermore, predictions in terms of the deposited and transmitted mass of medicine were possible. The methodology explained herein will be applicable to the morphologies that are to be obtained from an on-going clinical study

Os aerossóis e nuvens desenvolvem um papel muito importante nos processos climáticos terrestres por meio das suas contribuições diretas e indiretas no balanço radiativo da atmosfera. A dificuldade na previsão dos processos de mudanças climáticas estão associadas às incertezas na distribuição e propriedades dos aerossóis e nuvens, assim como em suas interações em escala global. Tendo como principal objetivo desenvolver estudos que ajudem na diminuição dessas incertezas, a NASA, em parceria com a agência espacial francesa CNES, desenvolveu a missão do Satélite CALIPSO, que possui a bordo um sistema Lidar denominado CALIOP capaz de estudar o perfil e a distribuição vertical dos aerossóis e nuvens e os processos de interação entre eles. Uma vez que as propriedade ópticas medidas pelo CALIOP são recuperadas utilizando um complexo conjunto de algoritmos, torna-se necessário o desenvolvimento de estudos e metodologias de validação para inferir qual a acurácia das medidas desse sistema. Nesse contexto, foi desenvolvida uma metodologia de avaliação e validação dos valores de Razão Lidar utilizados a priori pelos algoritmos do CALIOP utilizando dois instrumentos de sensoriamento remoto instalados em solo, um sistema Lidar de retroespalhamento elástico instalado no IPEN - São Paulo e o fotômetro solar da rede AERONET instalado em cinco diferentes localidades, Rio Branco - Acre (RB), Alta Floresta - Mato Grosso (AF), Cuiabá - Mato Grosso (CB), Campo Grande - Mato Grosso do Sul (CG) e São Paulo - São Paulo (SP). Foram determinados os dias de medidas correlativas entre os sistemas em solo e o CALIOP e analisados os dados para os dias de medidas com condições livre de nuvens e com trajetórias de massas de ar se deslocando das regiões de medidas do satélite para as regiões de medidas pelos instrumentos fixos. Foram calculados novos valores de Razão Lidar obtidos pelo Modelo Aeronet/Caliop (Modelo A/C) proposto. Esses valores mostraram-se coerentes com aqueles utilizados inicialmente pelo algoritmo do sistema CALIOP. Realizando uma comparação quantitativa, obteve-se uma diferença percentual de 2,17 ± 30,12%, esse valor mostra-se compatível com outros valores obtidos na literatura de validação desse sistema Lidar a bordo do Satélite CALIPSO. Essa subestimação nos valores de Razão Lidar utilizados pelo CALIOP pode estar ocorrendo devido um problema no processo de calibração dos dados do sistema CALIOP, uma vez que o território brasileiro se encontra na região da Anomalia do Atlântico Sul (SAA). A diferença percentual dos valores de Razão Lidar utilizados pelo CALIOP com aqueles obtido por meio de medidas com o sistema Lidar do IPEN forneceram valores de 2,34 ± 17,53%, demonstrando que o modelo de validação proposto é aceitável e acurácia nos valores de Razão Lidar utilizados a priori pelo CALIOP está dentro das margens de incerteza de 30%. / Aerosol and clouds play an important role in the Earths climate process through their direct and indirect contributions to the radiation budget. The largest difficulty in predicting the climate change processes is associated with uncertainties in the distribution and properties of aerosols and clouds, as well as their interactions on a global scale. The CALIPSO mission was developed as part of the NASA program, in collaboration with the French space agency CNES, with the main goal to develop studies that will help to quantify the uncertainties about aerosols and clouds. The CALIPSO satellite carried a Lidar system on board, named CALIOP, as a primary instrument, able to provide the aerosol and cloud vertical profiles and distribution, as well as their interactions. Once the optical properties measured by CALIOP are retrieved, using a complex set of algorithms, it is necessary to study and develop methodologies in order to assess the accuracy of the CALIOP products. In this context, a validation methodology was developed in order to verify the assumed values of the Lidar Ratio selected by the CALIOP algorithms, using two ground-based remote sensing instruments, an elastic backscatter Lidar system (MSP) installed at IPEN in São Paulo and the AERONET sunphotometers operating at five different locations in Brazil, Rio Branco - Acre (RB), Alta Floresta - Mato Grosso (AF), Cuiabá - Mato Grosso (CB), Campo Grande - Mato Grosso do Sul (CG) e São Paulo - São Paulo (SP). Those days when the CALIOP system and ground-based instruments spatially coincided, were selected and analyzed under cloud-free conditions, as well as days when the trajectories of air masses indicated the transport of air parcels from the CALIOP track towards the ground-based sensors. The Lidar Ratio values from the Aeronet/Caliop proposed model was determined and showed good consistency with those initially assumed by the CALIOP Algorithm. Based on the quantitative comparison, a mean difference of 2,17 ± 30,12%. This value shows to be in good agreement with other papers in the CALIPSO validation literature, demonstrating the accuracy of the proposed model. The apparent underestimation in the CALIOP Lidar Ratio values indicates a possible problem with the calibration process, since the Brazilian territory is in the so-called South Atlantic Anomaly (SSA) Region. The Lidar Ratio retrieved by the MSP-Lidar system at IPEN provided a mean difference of 2,34 ± 17,53%, confirming that the accuracy in the Lidar Ratio assumed a priori by the CALIOP algorithms is within the uncertainty range of 30%.

Os efeitos da interação entre aerossóis e nuvens foram estudados neste trabalho através da análise das propriedades ópticas de nuvens em função da profundidade óptica do aerossol (AOD). A região de trabalho foi a Amazônia, particularmente durante a estação seca e na transição entre a estação seca e a chuvosa, quando as queimadas lançam grande quantidade de partículas na atmosfera. Foram utilizados produtos derivados do MODIS (Moderate Resolution Imaging Spectroradiometer), sendo dois artigos utilizados como referência (Yu et al., 2007 e Koren et al., 2008). Observou-se comportamento de correlação entre fração de cobertura de nuvens e AOD conforme previsto em Koren et al. (2008) para outros anos estudados (2002 a 2008), nas estações seca e de transição entre seca e úmida, e em seis áreas menores de estudo de diferentes regiões da Amazônia, utilizando resultados das passagens da manhã (satélite Terra) e da tarde (satélite Aqua). Essas análises também foram realizadas restringindo-se os dados a situações atmosféricas semelhantes, conforme conteúdo de vapor dágua e instabilidade atmosférica, sendo observado o efeito microfísico através de médias, mas o radiativo não foi observado. / The effects of the interaction between aerosols and clouds are studied in this work by analyzing the optical properties of clouds as a function of the aerosol optical depth (AOD). The studied area is the Amazon region, particularly during the dry season and the transition between the dry to wet season, when fires release large amounts of particles in the atmosphere. MODIS (Moderate Resolution Imaging Spectroradiometer) products are used and two papers are used as reference (Yu et al., 2007 and Koren et al., 2008). As observed by Koren et al. (2008), correlation between cloud cover fraction and AOD was observed in this study, for a larger database, including years 2002 to 2008, both during the dry seasons and the transition between dry to wet. Six smaller areas in the Amazon were also investigated, using results from morning (Terra satellite) and afternoon (Aqua satellite) overpasses. These tests were also conducted by restricting the data according to atmospheric conditions such as water vapor content intervals and atmospheric instability. In this case, only the microphysical effect was observed, but not the radiative.

A região amazônica constitui um complexo ecossistema, integrando a floresta, o sistema hídrico e a atmosfera. A região tem passado por profundas mudanças no uso do solo, com a troca de floresta por pastagens e culturas agrícolas, alterando o funcionamento natural do ecossistema. Tais alterações vêm sendo estudadas pelo Experimento de Grande Escala da Biofera-Atmosfera na Amazônia (LBA). Fazendo uso do modelo MAPS (Model for Aerosol Process Studies), do tipo caixa de dimensão zero, foram simulados os processos dinâmicos de produção de aerossóis orgânicos a partir de precursores gasosos (VOCs - Volatile Organic Compounds), e da formação de núcleos de condensação de nuvens (CCN - Cloud Condensation Nuclei) na Amazônia. Os resultados deste trabalho mostram que o processo de conversão gás-partícula altera as propriedades físico-químicas da população de aerossóis e CCNs. A oxidação dos monoterpenos, compostos orgânicos voláteis emitidos pela vegetação, leva à produção de aerossóis secundários na moda fina. A conversão de floresta para pastagem reduz as emissões de monoterpenos, com uma conseqüente diminuição na produção de novas partículas orgânicas. Em 24 horas de simulação, o modelo MAPS calcula uma concentração de 2.0 ug/m POT.3 de aerossóis orgânicos secundários para o ambiente de floresta, em comparação com o valor de 0.69 ug/m POT.3 previsto para o ambiente de pastagem. A produção de aerossóis orgânicos secundários, devido à conversão gás-partícula, traz conseqüências para os processos de produção de CCN e formação de nuvens. A partir de uma população natural de aerossóis constituída majoritariamente por compostos orgânicos, o modelo prevê a ativação de 90% das partículas à supersaturação de 0.5%, evidenciando o papel dos aerossóis biogênicos orgânicos no processo de formação de nuvens na Amazônia. O material particulado das estações seca e chuvosa da Amazônia apresenta características muito diversas, ) no que diz respeito à distribuição de tamanho e de espécies químicas. A partir das propriedades físico-químicas dos aerossóis de queimadas, o modelo calculou uma concentração de 250 partículas de CCN por cm POT.3 a uma supersaturação de 0.15%, em oposição às 100 partículas de CCN por cm POT.3 produzidas a partir de aerossóis naturais, sob condições idênticas de umidade. A maior quantidade de CCNs na estação seca interfere nos processos físicos de produção de nuvens, podendo provocar uma diminuição da taxa de crescimento de gotas, um aumento no tempo de residência das nuvens, e a conseqüente redução da taxa de precipitação na Amazônia. / The Amazon Forest is a very complex ecosystem, which integrates its vegetation, its hydrological system, and the atmosphere. The Amazonian vegetation, with its natural metabolism, emits a large amount of biogenic particles and trace gases to the atmosphere. The region is passing through deep changes with respect to land use and land cover. The conversion of forest to pasture or agricultural land alters the ecosystem natural behavior. Using a zero dimensional box model named MAPS (Model for Aerosol Processes Studies),the dynamical processes of gas-to-particle conversion and cloud condensation nuclei (CCN) formation have been simulated for Amazonia. The parameters that constraint the model were based on data collected during the Large Biosphere-Atmosphere Experiment in Amazon (LBA). This work shows that gas-to-particle conversion processes affects the physical and chemical properties of natural aerosol population. Oxidation of monoterpenes, volatile organic compounds emitted by vegetation, causes a fine mode secondary organic aerosol production. The conversion of forest to pasture land reduces monoterpene emissions, diminishing the production of new organic particles as consequence. In 24 hours of simulation, the model predicts a secondary organic aerosol concentration of 2.0 g/m³ for forest, and 0.69 g/m³ for pasture environment. The production of secondary organic aerosol, due to gas-to-particle conversion, influences CCN population and cloud processes formation. From a natural aerosol population composed mainly by organic compounds, the model predicts that 90% of the particles activates at 0.5% of ambient supersaturation, showing the important role of organic aerosol on CCN formation in Amazon. Dry and wet season particulate matter in Amazonia shows very distinct characteristics of size and chemical species distribution. From a typical burning season aerosol, the model predicted a concentration of 250 CCN/cm³ at a supersaturation of 0.15%. With similar humidity conditions, a concentration of 100 CCN/cm³ was calculated from natural wet season aerosol. The increased number of CCN during the dry season affects cloud formation, and can reduce the growth rate of droplets, enlarge cloud lifetime, and consequently diminish cloud precipitation rates.

Os aerossóis e nuvens desenvolvem um papel muito importante nos processos climáticos terrestres por meio das suas contribuições diretas e indiretas no balanço radiativo da atmosfera. A dificuldade na previsão dos processos de mudanças climáticas estão associadas às incertezas na distribuição e propriedades dos aerossóis e nuvens, assim como em suas interações em escala global. Tendo como principal objetivo desenvolver estudos que ajudem na diminuição dessas incertezas, a NASA, em parceria com a agência espacial francesa CNES, desenvolveu a missão do Satélite CALIPSO, que possui a bordo um sistema Lidar denominado CALIOP capaz de estudar o perfil e a distribuição vertical dos aerossóis e nuvens e os processos de interação entre eles. Uma vez que as propriedade ópticas medidas pelo CALIOP são recuperadas utilizando um complexo conjunto de algoritmos, torna-se necessário o desenvolvimento de estudos e metodologias de validação para inferir qual a acurácia das medidas desse sistema. Nesse contexto, foi desenvolvida uma metodologia de avaliação e validação dos valores de Razão Lidar utilizados a priori pelos algoritmos do CALIOP utilizando dois instrumentos de sensoriamento remoto instalados em solo, um sistema Lidar de retroespalhamento elástico instalado no IPEN - São Paulo e o fotômetro solar da rede AERONET instalado em cinco diferentes localidades, Rio Branco - Acre (RB), Alta Floresta - Mato Grosso (AF), Cuiabá - Mato Grosso (CB), Campo Grande - Mato Grosso do Sul (CG) e São Paulo - São Paulo (SP). Foram determinados os dias de medidas correlativas entre os sistemas em solo e o CALIOP e analisados os dados para os dias de medidas com condições livre de nuvens e com trajetórias de massas de ar se deslocando das regiões de medidas do satélite para as regiões de medidas pelos instrumentos fixos. Foram calculados novos valores de Razão Lidar obtidos pelo Modelo Aeronet/Caliop (Modelo A/C) proposto. Esses valores mostraram-se coerentes com aqueles utilizados inicialmente pelo algoritmo do sistema CALIOP. Realizando uma comparação quantitativa, obteve-se uma diferença percentual de 2,17 ± 30,12%, esse valor mostra-se compatível com outros valores obtidos na literatura de validação desse sistema Lidar a bordo do Satélite CALIPSO. Essa subestimação nos valores de Razão Lidar utilizados pelo CALIOP pode estar ocorrendo devido um problema no processo de calibração dos dados do sistema CALIOP, uma vez que o território brasileiro se encontra na região da Anomalia do Atlântico Sul (SAA). A diferença percentual dos valores de Razão Lidar utilizados pelo CALIOP com aqueles obtido por meio de medidas com o sistema Lidar do IPEN forneceram valores de 2,34 ± 17,53%, demonstrando que o modelo de validação proposto é aceitável e acurácia nos valores de Razão Lidar utilizados a priori pelo CALIOP está dentro das margens de incerteza de 30%. / Aerosol and clouds play an important role in the Earths climate process through their direct and indirect contributions to the radiation budget. The largest difficulty in predicting the climate change processes is associated with uncertainties in the distribution and properties of aerosols and clouds, as well as their interactions on a global scale. The CALIPSO mission was developed as part of the NASA program, in collaboration with the French space agency CNES, with the main goal to develop studies that will help to quantify the uncertainties about aerosols and clouds. The CALIPSO satellite carried a Lidar system on board, named CALIOP, as a primary instrument, able to provide the aerosol and cloud vertical profiles and distribution, as well as their interactions. Once the optical properties measured by CALIOP are retrieved, using a complex set of algorithms, it is necessary to study and develop methodologies in order to assess the accuracy of the CALIOP products. In this context, a validation methodology was developed in order to verify the assumed values of the Lidar Ratio selected by the CALIOP algorithms, using two ground-based remote sensing instruments, an elastic backscatter Lidar system (MSP) installed at IPEN in São Paulo and the AERONET sunphotometers operating at five different locations in Brazil, Rio Branco - Acre (RB), Alta Floresta - Mato Grosso (AF), Cuiabá - Mato Grosso (CB), Campo Grande - Mato Grosso do Sul (CG) e São Paulo - São Paulo (SP). Those days when the CALIOP system and ground-based instruments spatially coincided, were selected and analyzed under cloud-free conditions, as well as days when the trajectories of air masses indicated the transport of air parcels from the CALIOP track towards the ground-based sensors. The Lidar Ratio values from the Aeronet/Caliop proposed model was determined and showed good consistency with those initially assumed by the CALIOP Algorithm. Based on the quantitative comparison, a mean difference of 2,17 ± 30,12%. This value shows to be in good agreement with other papers in the CALIPSO validation literature, demonstrating the accuracy of the proposed model. The apparent underestimation in the CALIOP Lidar Ratio values indicates a possible problem with the calibration process, since the Brazilian territory is in the so-called South Atlantic Anomaly (SSA) Region. The Lidar Ratio retrieved by the MSP-Lidar system at IPEN provided a mean difference of 2,34 ± 17,53%, confirming that the accuracy in the Lidar Ratio assumed a priori by the CALIOP algorithms is within the uncertainty range of 30%.

Liu Hua. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 139-143). / Abstracts in English and Chinese. / Table of Contents --- p.I / Acknowledgement --- p.VII / Abstract --- p.VIII / Abstract (Chinese) --- p.X / List of Tables --- p.XV / List of Figures --- p.XXIV / List Symbols and Abbreviations / Chapter Chapter One --- Introduction / Chapter 1.1. --- Rationale of study --- p.2 / Chapter 1.2. --- Drug Delivery to the lungs --- p.5 / Chapter 1.3. --- Particle transport and deposition mechanisms --- p.8 / Chapter 1.4. --- Factors affecting particulate interactions --- p.9 / Chapter 1.4.1. --- Particle size --- p.9 / Chapter 1.4.2. --- Particle shape --- p.10 / Chapter 1.4.3. --- Surface texture --- p.10 / Chapter 1.4.4. --- Surface energy --- p.11 / Chapter 1.4.5. --- Contact area --- p.12 / Chapter 1.4.6. --- Relative humidity --- p.12 / Chapter 1.4.7. --- Electrical properties --- p.13 / Chapter 1.5. --- Fine powder production technologies applicable to dry powder inhalation formulations --- p.13 / Chapter 1.5.1. --- Batch crystallization and micronization --- p.14 / Chapter 1.5.2. --- Spray drying --- p.15 / Chapter 1.5.3. --- Supercritical fluid crystallization --- p.17 / Chapter 1.6. --- Physical characterization of aerosol powders --- p.18 / Chapter 1.6.1. --- Microscopy and particle size analysis --- p.19 / Chapter 1.6.2. --- Powder X-ray diffractometry --- p.19 / Chapter 1.6.3. --- Thermal analysis --- p.20 / Chapter 1.6.4. --- In-vitro deposition assessment --- p.20 / Chapter 1.6.5. --- Surface energy measurement by inverse gas chromatography (IGC) --- p.21 / Chapter 1.7. --- Scope of study --- p.22 / Chapter Chapter Two --- Materials and Methods / Chapter 2.1. --- Materials --- p.25 / Chapter 2.2. --- Equipment --- p.25 / Chapter 2.3. --- Methods --- p.27 / Chapter 2.3.1. --- Determination of aqueous solubility of salbutamol sulphate in water --- p.27 / Chapter 2.3.2. --- Preparation of spray-dried salbutamol sulphate powders under different operating conditions --- p.27 / Chapter 2.3.3. --- Preparation of spray-dried salbutamol sulphate powders at various lecithin concentrations --- p.30 / Chapter 2.3.4. --- Preparation of spray-dried salbutamol sulphate powders at various oleic acid concentrations --- p.32 / Chapter 2.3.5. --- Physical characterization of spray-dried salbutamol sulphate powders --- p.34 / Chapter 2.3.5.1. --- Scanning electron microscopy --- p.34 / Chapter 2.3.5.2. --- Specific surface area determination --- p.34 / Chapter 2.3.5.3. --- Particle size distribution measurements --- p.35 / Chapter 2.3.5.4. --- Water content determination --- p.36 / Chapter 2.3.5.5. --- Isothermal water vapour sorption studies --- p.37 / Chapter 2.3.5.6. --- Powder X-ray diffraction --- p.37 / Chapter 2.3.5.7. --- Thermal analysis --- p.38 / Chapter 2.3.5.8. --- Surface energy measurement by inverse gas chromatography --- p.39 / Chapter 2.3.5.8.1. --- Calculation of surface thermodynamic parameters --- p.40 / Chapter 2.3.5.8.1.1. --- Standard Free Energy of Adsorption and Related Thermodynamic Parameters --- p.40 / Chapter 2.3.5.8.1.2. --- Dispersive Component of Surface Free Energy and Related Thermodynamic Parameters --- p.41 / Chapter 2.3.5.8.1.3. --- Specific Interactions and Associated Acid-Base Properties --- p.42 / Chapter 2.3.5.9. --- In-vitro deposition measurement by multi-stage liquid impinger --- p.43 / Chapter Chapter Three --- Results and discussion / Chapter 3.1. --- Influence of spray drying operating parameters --- p.46 / Chapter 3.1.1. --- Drying temperature --- p.46 / Chapter 3.1.1.1. --- "Particle size, particle morphology, and specific surface area" --- p.46 / Chapter 3.1.1.2. --- "Crystallinity, moisture sorption and thermal behaviour" --- p.53 / Chapter 3.1.1.3. --- Surface thermodynamic properties --- p.60 / Chapter 3.1.1.4. --- Aerodynamic properties and in-vitro deposition --- p.64 / Chapter 3.1.2. --- Feed solution concentration --- p.67 / Chapter 3.1.2.1. --- "Particle size, particle morphology and specific surface area" --- p.69 / Chapter 3.1.2.2. --- "Crystallinity, moisture sorption and thermal behaviour" --- p.69 / Chapter 3.1.2.3. --- Surfacethermodynamicproperties --- p.70 / Chapter 3.1.2.4. --- Aerodynamic properties and in-vitro deposition --- p.70 / Chapter 3.1.3. --- Feed speed --- p.72 / Chapter 3.1.3.1. --- "Particle size, particle morphology, and specific surface area" --- p.72 / Chapter 3.1.3.2. --- "Crystallinity, moisture sorption and thermal behaviour" --- p.73 / Chapter 3.1.3.3. --- Surfacethermodynamicproperties --- p.73 / Chapter 3.1.3.4. --- Aerodynamic properties and in-vitro deposition --- p.73 / Chapter 3.2. --- Influence of formulation additives --- p.78 / Chapter 3.2.1. --- Influence of lecithin as additive --- p.78 / Chapter 3.2.1.1. --- "Particle morphology, particle size and specific surface area" --- p.79 / Chapter 3.2.1.2. --- "Crystallinity, moisture sorption and thermal behaviour" --- p.84 / Chapter 3.2.1.3. --- Surfacethermodynamicproperties --- p.90 / Chapter 3.2.1.4. --- Aerodynamic properties and in-vitro deposition --- p.94 / Chapter 3.2.2. --- Influence of oleic acid as additive --- p.101 / Chapter 3.2.2.1. --- "Particle morphology, particle size and specific surface area" --- p.101 / Chapter 3.2.2.2. --- "Crystallinity, moisture sorption and thermal behaviour" --- p.106 / Chapter 3.2.2.3. --- Surfacethermodynamicproperties --- p.123 / Chapter 3.2.2.4. --- Aerodynamic properties and in-vitro deposition --- p.127 / Chapter Chapter Four --- Conclusion and Future Work / Chapter 4.1. --- Conclusion --- p.134 / Chapter 4.1.1. --- Influence of spray drying operating parameters --- p.134 / Chapter 4.1.2. --- Influence of formulation additives --- p.135 / Chapter 4.2. --- Future Work --- p.137 / References --- p.139

This thesis presents a new technique to identify a 2D mask showing the extent of particulate aerosol distributions in satellite imagery. This technique uses a supervised texture classication approach, and utilises data from two distinct satellite sources. The vertical feature mask (VFM) product from the CALIPSO lidar, provides an accurate description of the aerosol content of the atmosphere but has a limited footprint and coverage. The CALIPSO VFM is used to provide training data in order to for classiers to be applied to other imagery, namely data from the spinning enhanced visible and infrared imager (SEVIRI) on the MSG satellite. The output from the classication is a 2D mask representing the locations of the particulate aerosol of interest within the SEVIRI image. This approach has been demonstrated on test cases over land and ocean, and shows a good agreement with other techniques for the detection of particulate aerosol. However, the supervised texture approach provides outputs at a higher resolution than the existing methods and the same approach is applicable over land and ocean and therefore shows the advantages compared to the current techniques. Furthermore, the coverage of the approach can be further extended using signature extension and chain classication. Signature extension was applied to one of the test cases to monitor the same geographical region with temporal extension away from the initial supervised classication. The experiments showed that it was possible to extend the coverage for ±90 minutes from the original classication and indicates the possibility of greater extension over larger temporal windows.

by Tai Fai Fok. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (p. 211-215). / Microfiche. Ann Arbor, Mich. UMI, 1998. 3 microfiches ; 11 x 15 cm.