Thèses : « Particulate matte »

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Gomes, Nogueira Ana Paula. « Particulate Matter Emission Issues in Brake Systems ». Doctoral thesis, Università degli studi di Trento, 2022. http://hdl.handle.net/11572/348039.

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Automotive brake systems are source of particulate matter (PM) emissions, particularly in the urban areas. Several human ill-health are related with this kind of pollution. Along tire wear, road wear and dust from resuspension, the brake wear comprises the most relevant non-exhaust source of road traffic related emissions. Aiming at studying the PM brake emissions, this thesis is composed of an introductory part containing the main concepts and the state of art of the main subjects; and the experimental part, which comprehends three investigations. Chapters 2, 3, 4 and 5 are dedicated to the introduction part. Chapter 2 provides a brief description of the friction and wear, as well as the fundamental principles of braking by contact. Chapter 3 discuss the disc braking system, with particular attention to the pad friction materials. Chapter 4 is dedicated to friction layer: the layer usually developing at the disc/pad interface, affecting the performances of the tribological system. Finally, Chapter 5 provides an extensive discussion of the issues related to the particulate matter originated from disc brake systems. The experimental part is presented in the Chapters 6, 7, 8 and 9. Chapter 6 describes the methodology applied in all the investigations. Chapter 7 investigates the PM emissions behavior and its interaction with the friction and wear, aiming to identify the mechanism of generation the PM emissions. A copper-containing and a copper-free commercial friction materials were used, with particular emphasis on the effect of the scorching treatment. The Chapter 8 is dedicated at investigating the tribological behavior and the corresponding PM emissions in two Cu-free commercial friction materials, aiming to a better understanding the effect of abrasive ingredients on the emissions generation. Finally, the Chapter 9 investigated the addition of natural ingredient rice husk in a new eco-friendly Cu-free brake friction material composition, focusing the attention on the tribological and emissions behavior. All tests were carried out using a pin-on-disc tribometer equipped with an enclosure, especially designed for investigating the tribological properties, as well as the airborne particles generated by contact. Low-metallic friction materials, both commercial and laboratory-produced, were tested against cast iron discs. The tests parameters used correspond to mild sliding conditions resembling those faced in real braking. Such conditions are characteristic of driving in urban areas, where the expose to traffic PM is concentrated. A specific methodology of analysis was developed, based on SEM/EDXS techniques. Using this methodology, comparative investigations between the elemental composition of the virgin friction materials, the worn surfaces of the friction materials and the airborne particles collected during the tribological tests were carried out. The results point out the triboxidative wear as the main mechanism of the PM brake emissions generation. Moreover, particles produced by abrasive wear can be also directly emitted to the environment.

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Costa, Talitha Lopes Ferreira da. « Origem e composição da matéria orgânica particulada no complexo estuarino-lagunar de Mundaú-Manguaba utilizando lipídios como marcadores moleculares ». Universidade do Estado do Rio de Janeiro, 2010. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=1626.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
O Complexo Estuarino Lagunar Mundaú-Manguaba está sofrendo um processo acelerado de degradação ambiental devido a muitas atividades antrópicas como crescimento urbano desordenado, processamento de cana-de-açúcar, pecuária, efluentes industriais e domésticos. O objetivo deste trabalho é avaliar a composição e distribuição do material particulado em suspensão através de traçadores geoquímicos orgânicos para identificar as fontes potenciais e os padrões de mistura da matéria orgânica no CELMM durante duas campanhas: uma realizada no período seco e a outra no período úmido. As amostras de água foram coletadas na superfície (< 1 m de profundidade), utilizando garrafas de vidro de 4L de capacidade. Os n-alcoois, esteróis e ácidos graxos foram extraídos por Soxhlet e analisados por cromatografia em fase gasosa acoplada a espectrometria de massas. Considerando os resultados obtidos, constatou-se que há uma predominância de matéria orgânica autóctona em ambos os períodos de amostragem no sistema em questão. Contudo, também foi observada a presença de fontes alóctonas e antrópicas, tendo estas uma menor influência durante o período seco.
The Mundaú-Manguaba estuarine lagoon system is located in Maceió, Alagoas, Brazil. This region has been suffering an accelerated process of environmental degradation through many antropic activities like urban growth, sugar-cane processing, cattle breeding, industrials waste and sewage. The aim of this work is to evaluate the suspended particulate matter composition and distribution with organic geochemistry markers to identify the potential sources and mixing processes in the system during the wet and the dry period. The water samples were collected at the surface (<1m of depth), using a 4L glass bottle. Lipids were extracted by Soxhlet and quantified by gas chromatography-mass spectrometry. Considering the obtained results, a predominance of autochthonous sources of organic matter was established for the system. However, the presence of alochthonous and anthropic also was observed with lower influence during the dry period.

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Gómez, Ana Maria Mosquera. « Modelagem da dispersão de material particulado na atmosfera a partir de fontes estacionárias utilizando fluidodinâmica computacional ». Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-24102017-151559/.

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Neste trabalho propõe-se uma análise da dispersão de material particulado gerado por fontes estacionárias, aplicando ferramentas de Fluidodinâmica Computacional (em inglês Computatonal Fluid Dynamics, CFD), usando um modelo Euleriano para o escoamento e Lagrangeano para as partículas, em estado estacionário no software Fluent. A verificação da modelagem é apresentada em duas sessões, a primeira compreende o estudo do escoamento atmosférico em condições de estabilidade neutra incluindo os efeitos das heterogeneidades do terreno, no caso, um monte de 126m de altura em escala real. Foram comparados diferentes modelos de turbulência: padrão, RNG e parametrizado para o caso atmosférico. Os três modelos apresentaram desempenho semelhante e descrevem satisfatoriamente as tendências dos dados experimentais. A segunda, o modelo lagrangeano baseado no tempo de vida dos turbilhões (em inglês Discrete Random Walk, DRW) foi utilizado para representar a distribuição de concentrações de material particulado em um ambiente confinado. Os resultados numéricos descrevem satisfatoriamente os perfis de concentrações das partículas, porém subestimam os valores na região próxima à parede, o que indicaria que uma melhor aproximação da deposição das partículas deve ser considerada. Após estes estudos, esta abordagem euleriana-lagrangeana foi aplicada ao caso da dispersão de material particulado em condições de atmosfera neutra em uma região do Polo Cerâmico de Santa Gertrudes-SP, local responsável pela maior produção de revestimentos cerâmicos do Brasil. O trânsito de caminhões nas estradas não pavimentadas foi identificado como fonte de material particulado que atinge o perímetro urbano da cidade. Estudaram-se também as contribuições das atividades referentes à exploração das minas de argila e a preparação do solo para uso agrícola, apesar desta última não soma uma carga relevante ao ser comparada com as duas anteriores. Além da influência das fontes mencionadas, fontes de origem industriais localizadas dentro da cidade também foram consideradas no cenário.
In this study an analysis of the dispersion of particulate matter generated by stationary sources is proposed, by applying Computational Fluid Dynamics (CFD) tools, using an Eulerian model for the flow and a Lagrangean model for the particles, under steady-state conditions in the Fluent software. The model validation is presented in two sessions, the first comprises the study of the atmospheric flow under conditions of neutral stability, including the effects of the heterogeneities of the terrain. In this case, the air flow past a 126m high hill in real scale was adopted. Different turbulence models were compared: standard k-?, k-? RNG and parametrized k-?. The three models presented similar performance and described satisfactorily the trends of the experimental data. Subsequently, the Lagrangean model based on the Eddy life time (DRW - Discrete Random Walk) was used to represent the distribution of particulate matter concentrations in a confined environment. The numerical results satisfactorily describe the particle concentration profiles, but underestimate the values in the region near the wall, which would indicate that a better approximation of the particle deposition should be considered. After these studies, this Eulerian- Lagrangean approach was applied to the case of dispersion of particulate material under neutral atmosphere conditions in a region around the city of Santa Gertrudes-SP, where the Ceramic Complex is responsible for the largest production of ceramic tiles in Brazil. Transit of trucks on unpaved roads has been identified as a source of particulate matter that reaches the urban perimeter of the city. The contributions of the activities related to mining and the preparation of the soil for agricultural use were also studied, although this last one does not add a significant load when compared with the two previous ones. In addition to the influence of the mentioned sources, industrial sources located inside the city also contribute to the scenario.

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Faccio, Andréa Tedesco. « Abordagem metabolômica no estudo da exposição gestacional à poluição atmosférica ». Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-07122015-101244/.

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Há fortes evidências dos efeitos negativos da exposição gestacional a poluentes atmosféricos. No entanto, mecanismos de atuação de poluentes não são bem compreendidos. Alterações fisiológicas anômalas na progenitora, durante o período de gravidez, podem causar mudanças permanentes na prole, que podem desencadear futuras doenças na vida adulta. Portanto, o estudo dessas alterações maternas é importante. A metabolômica é definida como a análise global do metaboloma de um organismo em experimentos comparativos, com o objetivo de observar mudanças relativas da abundância dos metabólitos, o aparecimento ou desaparecimento de metabólitos, e pode fornecer uma melhor compreensão dos mecanismos de funcionamento celular dos organismos a nível molecular. Nesse trabalho, um estudo experimental de exposição gestacional materna, ao material particulado fino (MP2,5), foi realizado, para avaliar os efeitos dessa exposição no metabolismo, por meio da análise metabolômica global da urina de camundongos fêmeas progenitoras expostas ao MP2,5 (grupo teste) ou a ar filtrado (grupo controle) durante a gestação. Um método cromatográfico e de preparo de amostra para metabolômica urinária por HILIC-MS foram otimizados. Para a otimização da condição cromatográfica, foram investigados a influência de aditivos, concentração de sal e pH da fase móvel, bem como, a rampa do gradiente. A melhor condição foi escolhida por meio da avaliação do formato de pico, da intensidade relativa e do CV do tempo de retenção para 15 m/z selecionados, assim como, pelo número total de molecular features e CV da intensidade desses molecular features. A melhor condição obtida apresenta 20 mmol/L de formiato de amônio em sua composição do solvente B da fase móvel e 95% acetonitrila e 5% solução aquosa 400 mmol/L de formiato de amônio na composição do solvente A. Para o preparo de amostra, foram examinados diferentes solventes orgânicos e suas misturas, para a precipitação de proteínas da urina. O isopropanol foi o solvente apresentou os melhores resultados para o preparo de amostra. Dessa forma, com o método analítico otimizado, as amostras de urina de camundongos fêmeas prenhas foram submetidas à analise metabolômica global por HILIC-MS. O metaboloma dos animais foi bastante alterado pela exposição gestacional ao material particulado. Observou-se alteração dos níveis de carnitinas, aminoácidos, peptídeos, entre outros. Há também indícios de que a poluição atmosférica alterou a microbiota intestinal dos animais, devido ao aumento de N-óxido de trimetilamina, um metabólito que também é relacionado ao processo de aterosclerose. Níveis de metabólitos relacionados ao metabolismo da histidina também foram alterados devido a exposição ao MP2,5. Níveis de carnitina e acilcarnitinas foram aumentados no teste, sugerindo alteração da produção de energia na mitocontria.
There are strong evidences regarding negative effects of gestational exposure to air pollution. However, the mechanisms of action of air pollutants are not well established. Maternal anomalous physiological changes during pregnancy may cause permanent changes in offsprings, that might initiate future diseases in adult life. Therefore, the study of those maternal changes during pregnancy is important. Metabolomics is defined as the global analysis of the metabolome of an organism in comparative studies, for the measurement of relative changes in the metabolite abundance, appearance or disappearance. Metabolomics might provide a better understanding of cellular functioning at the molecular level. In this work, an experimental study of maternal gestational exposure to fine particulate matter (PM2.5) was accomplished to evaluate the effects of this exposure to the metabolism, by an untargeted metabolomics analysis of urine from pregnant mice exposed to PM2.5 or to filtered air during pregnancy. A chromatographic and sample preparation methods for urinary untargeted metabolomics analysis by HILIC-MS were optimized. For the chromatography optimization, the influence of mobile phase additives, salt concentration and pH, as well as, the gradient ramp were investigated. The best condition was chosen by the evaluation of peak shape, relative intensity and retention time CV of 15 selected m/z, as well as, the total number of molecular features and the intensity CV of those molecular features. The best condition comprises of 20 mmol/L of ammonium formate as solvent B, and 95% acetonitrile and 5% 400 mmol/L of ammonium formate as solvent A, in the composition of the mobile phase. For the sample preparation, different solvents, along with, their mixtures were examined for the urine protein precipitation. Isopropanol was the solvent that presented the best results for sample preparation. Thus, after the analytical method optimized, urine samples from the progenitors were submitted to untargeted metabolomics analysis by HILIC-MS. The animals\' metabolome were significantly changed by the gestational exposure to particulate matter. It was observed changes in the levels of carnitines, amino acids, peptides, among others. There is some indication that the air pollution has altered the gut microbiota, due to the enhancement of trimethylamine N-oxide (TMAO), a metabolite that is also related to the atherosclerosis process. The level of metabolites related to histidine metabolism were also altered due to PM2.5 exposure. Carnitine and acylcarnitine levels were also increased in the test group, suggesting an altered energy production in the mitochondria.

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Souza, Milena Gouveia Oliveira de. « Avaliação da concentração de arsênio em partículas fracionadas por tamanho na atmosfera do Recôncavo Baiano ». reponame:Repositório Institucional da UFBA, 2011. http://www.repositorio.ufba.br/ri/handle/ri/10027.

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Atualmente, um dos maiores problemas mundiais é a poluição atmosférica, oriunda essencialmente de fontes antrópicas. Os grandes impactos ambientais, como a degradação da qualidade do ar, são resultados dos processos de desenvolvimento urbano e industrial. O material particulado (MP) tem sido alvo de vários estudos devido aos efeitos nocivos causados ao meio ambiente e a saúde humana. O arsênio, um metalóide que apresenta características tanto de metal como de não-metal, é considerado altamente tóxico. A associação do arsênio ao material particulado pode provocar sérios danos à saúde da população. Os níveis de toxicidade do arsênio são dependentes de sua forma química. As espécies inorgânicas de arsênio, arsenito (AsIII) e arseniato (AsV), são também consideradas agentes carcinogênicos. O Recôncavo Baiano é uma região que apresenta grande importância ambiental, social e econômica para o estado da Bahia. Nesta área encontram-se portos, terminais marítimos e diversos pólos industriais que são as principais fontes de emissão de poluentes para o meio ambiente. O presente trabalho teve por objetivo verificar a concentração do arsênio presentes tanto nas partículas finas, quanto nas partículas grossas do material particulado atmosférico do Recôncavo Baiano, para avaliar as contribuições deste poluente à saúde da população exposta. A determinação de arsênio em material particulado, utilizando a digestão, com HNO3, e a técnica de espectrometria de fluorescência atômica acoplada à geração de hidreto (HG-AFS), mostrou-se eficiente para a matriz estudada com limite de detecção e quantificação de 0,3 ng m-3 e 1 ng m-3, respectivamente. As concentrações médias de arsênio, obtidas no material particulado em algumas regiões do Recôncavo Baiano, estavam em torno de 30 ng m-3, valor cinco vezes maior que o recomendado pela União Européia (6 ng m-3). O arsênio presente no material particulado encontra-se substancialmente nas partículas finas. Alertando para os riscos de exposição da população, nos municípios onde foram feitas as amostragens. Os resultados apresentados neste trabalho são indicativos da necessidade de se atualizar os padrões de qualidade do ar para o Brasil, incluindo outros poluentes como o arsênio
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Golly, Benjamin. « Etude des sources et de la dynamique atmosphérique de polluants organiques particulaires en vallées alpines : apport de nouveaux traceurs organiques aux modèles récepteurs ». Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENA019/document.

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Récemment, la qualité de l'air dans la région Rhône-Alpes est devenue un sujet sensible depuis sa mise en demeure par l'Union Européenne pour non respect des normes en vigueurs concernant les taux de particules fines (PM). Effectivement, certaines zones géographiques de la région connaissent de nombreux dépassements en PM10, particulièrement dans les vallées alpines durant la période hivernale. Ces dépassements en particules sont aussi accompagnés de fortes concentrations en composés organiques comme les hydrocarbures aromatiques polycycliques (HAP) constituants ces PM. Un accroissement des connaissances sur les sources de pollution atmosphérique particulaire et leurs dynamiques au sein des vallées alpines est alors nécessaire, ceci afin d'améliorer la mise en place des politiques de diminution des émissions grâce à une meilleure connaissance de l'influence des différentes sources au niveau régional. Ces travaux de thèse sont axés autour des émissions des sources industrielles encore mal connues et plus particulièrement l'industrie du carbone très présente dans les bassins industriels de ces fonds de vallées. Les approches classiques par les éléments métalliques n'étant pas spécifiques, l'exploration de la fraction organique a permis de proposer un profil chimique organique complet et d'avancer le benzo(b)naphtho(2,1-d)thiophène (BNT(2,1)), composé particulaire majoritaire de la famille des Hydrocarbures Aromatiques Polycycliques soufrés (HAPS) comme traceur de cette source. Ce composé a été détecté et quantifié sur plusieurs sites en proximité d'activités industrielles confirmant ainsi sa source potentielle. De plus le profil industriel a été introduit comme profil « source » afin d'évaluer sa robustesse dans les méthodologies de type modèle récepteur de bilan de masse comme le « Chemical Mass Balance » (CMB) et statistique comme la « Positive Matrix Factorization » (PMF). Les résultats ont confirmé l'intérêt de l'ajout des composés organiques à ces méthodologies. Ainsi, le profil industriel et les composés organiques HAPS ont permis de mieux tracer la source appelée génériquement « industrie du carbone » (combustions de charbon, de coke et de matériaux graphitiques) dans les vallées alpines mais aussi sur différents sites urbains français. En parallèle, un modèle de régression non linéaire multivarié (MRNL) a été développé pour la quantification des sources de HAP, basé sur l'utilisation de traceurs spécifiques de source (lévoglucosan, hopanes….) et de données météorologiques (gradient thermique). Son application a été validée sur un ensemble de sites alpins des vallées de l'Arve et de la Tarentaise. Un couplage entre ce modèle et les données de mesures optiques du carbone suie (BC) par aéthalomètre, a permis de proposer une solution aux mauvais résultats de corrélation entre les HAP mesurés et modélisés par le modèle MRNL sur le site de la vallée de la Maurienne. Ces faibles corrélations peuvent être liées à une mauvaise représentativité des composés organiques utilisés à tracer correctement les sources d'émission sur certains sites.Enfin, l'inter-comparaison de ces méthodologies pour la détermination des sources de HAP et plus particulièrement de la source industrielle permet de valider cette méthodologie dans une perspective opérationnelle de suivi des sources de HAP sur ces différents sites. Ces travaux réalisés au cours de cette thèse mettent en évidence l'intérêt de la caractérisation de la fraction organique des PM et les biais qui peuvent exister sur l'utilisation des composés organiques pour l'étude des sources d'émissions. Des alternatives y sont proposées afin de soulever ces ambiguïtés et d'améliorer l'étude des sources de HAP par les modèles récepteurs
Recently, Air quality has become a sensitive topic for Rhône-Alpes region due to the formal notice which was addressed by the European Commission for non-compliance with legislation in force. Indeed, certain geographic areas in the region present a lot of overruns in PM10, especially in Alpine valleys during winter. These overruns particles are also accompanied by high concentrations of organic compounds such as polycyclic aromatic hydrocarbons (PAHs), which constitute these PMs. An increase in khowledge about the sources of particulate air pollution and their dynamics in Alpine valleys is necessary, in order to improve the implementation of policies to reduce emissions through better knowledge of the influence of different sources at regional level. This thesis is focused around emissions from industrial sources still poorly known and particularly of the carbon industry highly present in these industrial areas of the valley bottoms. Traditional approaches by metallic elements being not specific, exploration of the organic fraction allowed to propose a complete organic chemical profile. In addition they led us to evidence the benzo(b)naphtho(2,1-d)thiophene (BNT(2,1)), the most abundant particulate compound of the family of sulfur-containing polycyclic aromatic hydrocarbons (PASHs), as a tracer of this source. This compound was detected and quantified on multiple sites in near industrial activities confirming its potential source. In addition the industrial profile was introduced as profile “source” in order to assess its robustness in methodologies of receptor model like the “Chemical Mass Balance “(CMB) and the “Positive Matrix Factorization” (PMF). The results confirmed the interest of the addition of organic compounds to these methodologies. Thus, the industrial profile and the PASHs compounds have allowed to better trace the source usually called “carbon industry” (coal, coke and graphite materials combustions) in the Alpine valleys but also in different French urban sites. In parallel, a non linear regression model (NLRM) was developed to PAH source apportionment, based on the use of specific molecular markers (levoglucosan, hopanes…) and of meteorological data (altitudinal temperature lapse rate). Its implementation has been validated on a set of sites of the Alpine valleys of Arve and Tarentaise. Coupling between this model and the optical measurements of black carbon (BC) by aethalometer, allowed to propose a solution to the poor performance of correlation between PAHs measured and modeled by NLRM model on this site of the Maurienne valley. These low correlations may be related to poor representativeness of organic compounds used to correctly trace the emission sources at some sites. Finally, the inter-comparison of these methodologies for the determination of PAH sources and especially of industrial source allows to validate this methodology in an operational perspective of monitoring of PAH levels on these sites. The work performed during this thesis highlights the interest of the characterizatin of the organic fraction of PM and the biases that may exist on the use of organic compounds for the study of the emission sources. Some alternatives are suggested to clarify ambiguities and improve the source apportionment of PAHs by receptor models

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Válio, Vinícius Mori. « Análise do material particulado atmosférico em uma região de São Carlos-SP ». Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-13082015-144101/.

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O presente trabalho avaliou a qualidade do ar de uma área central da cidade de São Carlos-SP, mais precisamente no campus 1 da Universidade de São Paulo. Nessa região há grande movimentação de pessoas e veículos, principalmente durante o horário comercial. Esta avaliação foi feita com base na determinação de um dos parâmetros utilizados para verificar a qualidade do ar, o material particulado (MP) inalável em suspensão, ou seja, partículas que possuem diâmetro aerodinâmico menor ou igual a 10 μm e podem penetrar no sistema respiratório, sendo portanto, nocivas à saúde humana. O MP foi determinado em suas frações de 2,5 e 10 μm de diâmetro (MP10 e MP2,5). Duas metodologias diferentes foram utilizadas para determinar a concentração do material particulado em suspensão, fotometria por espalhamento de luz, através do equipamento ADR-1500 e gravimetria, através do PEM (Personal Enviromental Monitor). Os valores obtidos pelo método gravimétrico foram superiores aos resultados encontrados através da fotometria. As concentrações obtidas foram comparadas com os limites recomendados pela Organização Mundial da Saúde para o MP em suas frações de 2,5 e 10 μm, iguais respectivamente a 25 e 50 μg/m3. Além do material particulado foram obtidos dados para temperatura, umidade relativa e precipitação. As médias obtidas para as concentrações de MP10 e MP2,5, com o método gravimétrico, o qual fornece os resultados mais confiáveis, foram iguais respectivamente a 48,8 e 23,1 μg/m3, muito próximas portanto, de seus limites correspondentes. As menores concentrações obtidas para o MP10 foram, em sua maioria, verificadas em dias chuvosos, tanto através do PEM como do ADR. As concentrações de MP2,5, obtidas somente através do PEM, também apresentaram os menores valores em dias com chuva. Foi desenvolvido um modelo matemático que prevê o comportamento do MP10 durante as precipitações, evento este que se mostrou o mais importante na influência da concentração de material particulado atmosférico.
This study evaluated the air quality of a central area of the city São Carlos-SP, more precisely on the Campus 1 of the University of São Paulo. In this region there is a large movement of people and vehicles, manly during business hours. This evaluation was made based on determination of one parameter used to verify air quality, the inhalable particulate material (PM) suspended in the air, in other words, particles which have aerodynamic diameter less or equal to 10 μm and can penetrate in the respiratory system, therefore, harmful to human health. The PM was determined in its fractions from 2,5 and 10 μm of diameter (PM10 e PM2,5).). Two different methodologies were used to determinate the concentration of particulate suspended material, photometry by scattered light, using the equipment ADR-1500, and gravimetry, thru PEM (Personal Environmental Monitor). The data obtained from gravimetry were higher than the results found thru photometry. The concentrations found were compared to the limits recommended by World Health Organization for PM and its fractions of 2,5 and 10 μm, equal to 25 and 50 μg/m3. Besides PM, temperature, relative humidity and precipitation were measured. The average values for the concentrations of PM10 and PM2,5 , using gravimetry, which provide more reliable results, it were equal to 48,8 and 23,1 μg/m3, therefore really close to their corresponding limits. The lower concentrations seen for PM10 were, mostly, verified on rainy days, using PEM and ADR. The concentrations of PM2,5 , obtained just using PEM, also had the lowest values during rainy days. A mathematical model was developed to predict PM10 behavior during precipitations, this event has shown to have the most important influence on the concentration of atmospheric particulate matter.

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Sánchez, Soberón Francisco. « Assessment of the human health risks and toxicity associated to particles (PM10, PM2.5 and PM1), organic pollutants and metals around cement plants ». Doctoral thesis, Universitat Rovira i Virgili, 2018. http://hdl.handle.net/10803/525816.

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Les partícules en suspensió (PM) són el contaminant aeri més perillós per a la salut humana. Aquestes es componen de partícules sòlides i líquides que floten a l’aire i que tenen mida i composició química diversa. Les PM solen classificar-se segons la seva mida. Així, aquelles que presenten un diàmetre menor de 10 micres es nomenen PM10, les menors de 2,5 micres es coneixen com PM2.5, i les menors de 1 micres es nomenen PM1. Una de les indústries tradicionalment reconegudes com a font de PM són les cimenteres. Encara que hi ha nombrosos estudis dedicats a les PM al voltant de cimenteres, aquests solen enfocar-se en les PM10, ignorant la importància d'aquelles més petites, i que poden arribar a zones més profundes de l'aparell respiratori. En la present tesi es van recollir PM10, PM2.5 i PM1 en una àrea influenciada per una cimentera durant diferents estacions. Posteriorment, es va dur a terme una caracterització fisicoquímica d'aquestes partícules, per estudiar els seus riscos inhalatoris i contribució de la cimentera al total de PM ambiental. A més, part d'aquestes partícules es van dedicar a fer assajos in-vitro amb cèl·lules respiratòries, per avaluar la seva toxicitat. Els majors nivells de PM es van registrar a l'hivern. A més, es va trobar que més del 60% de les partícules respirables són PM1. Aquesta última fracció va contenir els majors nivells d'alguns metalls pesats i hidrocarburs policíclics, presentant els majors riscos per a la població. Les proves in-vitro van revelar que la fracció fina (PM2.5) donava lloc a una toxicitat general més gran que les PM10. Finalment, la contribució de la cimentera al total de PM ambiental va resultar patent i dependent de l'estat productiu de la planta. Els resultats d'aquesta tesi mostren la importància d'estudiar les partícules fines (PM2.5 i PM1) en entorns influenciats per fàbriques de ciment.
Las partículas en suspensión (PM) son el contaminante aéreo más peligroso para la salud humana. Éstas se componen de partículas sólidas y líquidas que flotan en el aire y que tienen tamaño y composición química diversa. Las PM suelen clasificarse según su tamaño. Así, aquellas que presentan un diámetro menor de 10 µm se nombran PM10, las menores de 2,5 µm se conocen como PM2.5, y las menores de 1 µm se nombran PM1. Una de las industrias tradicionalmente reconocidas como fuente de PM son las cementeras. Aunque hay numerosos estudios dedicados a las PM alrededor de cementeras, éstos suelen enfocarse en las PM10, ignorando la importancia de aquéllas más pequeñas, y que pueden llegar a zonas más profundas del aparato respiratorio. En la presente tesis se recogieron PM10, PM2.5 y PM1 en un área influenciada por una cementera en diferentes estaciones. Posteriormente, se llevó a cabo una caracterización fisicoquímica de estas partículas, para estudiar sus riesgos inhalatorios y contribución de la cementera al total de PM ambiental. Además, parte de estas partículas se dedicaron a hacer ensayos de in-vitro con células respiratorias, para evaluar su toxicidad. Los mayores niveles de PM se registraron en invierno. Además, se encontró que más del 60% de las partículas respirables son PM1. Esta última fracción contuvo los mayores niveles de algunos metales pesados e hidrocarburos policíclicos, presentando los mayores riesgos para la población. Las pruebas in-vitro revelaron que la fracción fina (PM2.5) daba lugar a una toxicidad general mayor que las PM10. Por último, la contribución de la cementera al total de PM ambiental resultó patente y dependiente del estado productivo de la planta. Los resultados de esta tesis muestran la importancia de estudiar las partículas finas (PM2.5 y PM1) en entornos influenciados por fábricas de cemento.
Particulate matter (PM) is the most dangerous air pollutant for human health. Particulate matter is composed of solid and liquid particles floating in the air and having different size and chemical composition. PMs are usually classified according to their size. Thus, those with a diameter smaller than 10 μm are named PM10, those smaller than 2.5 μm are known as PM2.5, and those smaller than 1 μm are referred as PM1. Cement plants are one of the industries traditionally recognized as sources of PM. Although there are numerous studies dedicated to PM around cement factories, they tend to focus on PM10, ignoring the importance of smaller PM, which can reach deeper areas of the respiratory system. In the present thesis PM10, PM2.5 and PM1 were collected in an area influenced by a cement plant in different seasons. Subsequently, a physicochemical characterization of these particles was carried out to study their inhalation risks and the cement plant's contribution to the total environmental PM. In addition, to evaluate their toxicity part of these particles was dedicated to performing in-vitro tests with respiratory cells. The highest PM levels were recorded in winter. In addition, it was found that more than 60% of the respirable particles are PM1. This last fraction contained the highest levels of some heavy metals and polycyclic hydrocarbons, presenting the greatest risks for the population. In-vitro tests revealed that the fine fraction (PM2.5) resulted in a higher overall toxicity than PM10. Finally, the contribution of the cement company to the total environmental PM was clear and dependent on the productive state of the plant. The results of this thesis highlight the importance of studying fine particles (PM2.5 and PM1) in environments influenced by cement factories.

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Alves, Leandro Augusto Bassi. « Avaliação da qualidade ambiental de estabelecimentos comerciais da região central de São Carlos, SP ». Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-03102013-113541/.

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Este estudo apresenta o diagnóstico da qualidade do ambiente interno de estabelecimentos comerciais da região central da cidade de São Carlos, localizada no interior do estado de São Paulo. Foram determinados os seguintes parâmetros: concentração mássica do material particulado em suspensão, em suas frações MP10 e MP2,5, níveis de ruído, temperatura e umidade relativa. A coleta de dados foi realizada em três locais por um período de sete horas diárias, das 10 h às 17 h. Os estabelecimentos comerciais da região central da cidade de São Carlos possuíram, em média, valores de temperatura 5,1°C maiores e de umidade relativa 35,5% menores que aqueles encontrados na estação meteorológica localizada na área rural da cidade. Foi encontrado alto coeficiente de correlação entre os dados climáticos das lojas e da estação meteorológica, indicando que o ambiente externo possui grande influência nos ambientes internos estudados. Do total dos dias amostrados, 54% foram indicados como desconfortáveis termicamente. As concentrações de MP2,5 variaram de 11,4 a 40,6 μg.m-3, estando acima do padrão de referência de 24 h da OMS (25 μg.m-3) em 35% dos dias amostrados. As concentrações de MP10 variaram de 18,4 a 85,7 μg.m-3, estando acima do padrão de referência de 24 h da OMS (50 μg.m-3) em 33% dos dias amostrados. A razão interno/externo (I/E) do material particulado foi em média de 0,82 para o MP2,5 e de 0,86 para o MP10. A concentração média das amostras de material particulado realizadas na estação seca foi 1,8 vezes maior do que das amostras realizadas na estação chuvosa para o MP10 e 1,2 vezes maior para o MP2,5. A razão MP2,5/MP10 média das amostras foi de 56%. O coeficiente de correlação entre os equipamentos utilizados para medida do material particulado foi de 0,40 para o MP2,5 e 0,53 para o MP10, sendo que as concentrações obtidas pelo equipamento contador de partículas foram em média 4,2 e 2,0 menores que as concentrações obtidas pelo equipamento gravimétrico para o MP2,5 e MP10, respectivamente. Os dados de ruído variaram de 50,6 a 67,2 dBA no ambiente interno e de 56,6 a 72,8 dBA no ambiente externo, com uma razão I/E média de 0,91. Com relação ao limite de 70 dBA estipulado pela OMS, 9% dos dias amostrados no ambiente externo ultrapassaram este valor. O ponto amostral mais ruidoso foi aquele localizado em frente à via com maior tráfego de veículos, e o menos ruidoso era localizado em frente a uma via com tráfego frequentemente congestionado.
This study presents the indoor environmental quality of stores in central São Carlos, an inner city of the state of São Paulo, in Brazil. The following parameters were monitored: mass concentration of particulate matter, in its fractions PM10 and PM2.5, noise levels, temperature and relative humidity. Data was collected in three stores in the center of town during seven hours daily, from 10 a.m. to 5 p.m. The stores had, in average, temperature values 5.1 °C higherand relative umidity 35.5% lower than those observed in a weather station located in the countryside. High correlation coefficient between the climate data in the stores and in the weather station was found, indicating that the external environment has great influence in the internal environments studied. Of all samples, 54% indicated thermal discomfort. PM2.5, mass concentrations ranged from 11.4 to 40.6 μg.m-3, exceeding the 24 h WHO guideline (25 μg.m-3) in 35% of the samples. PM10 mass concentrations ranged from 18.4 to 85.7 μg.m-3, exceeding the 24 h WHO guideline (50 μg.m-3) in 33% of the samples. The average inside/outside (I/O) ratio of the particulate matter was of 0.84 for the PM2.5 and 0.88 for the PM10. Mass concentration was 1.8 times greater in the dry season than in rainy season for the PM10, and 1.2 times greater for the PM2.5. Average PM2.5/PM10 ratio was 56%. Correlation coefficient between the gravimetric and particle counter equipments used to determine PM mass concentration was of 0.40 for the PM2.5 and 0.53 for the PM10, and latter had average means 4.2 and 2.0 times smaller, for PM2.5 and PM10, respectively. Noise levels ranged from 50.6 to 67.2 dBA in the internal environment and 56.6 to 72.8 dBA in the external environment, with an average I/O ratio of 0.91. Concerning the 70 dBA daily exposure limit estipulated by WHO, 9% of the sampled days exceeded that value. The location with higher noise pollution was located in front of the street with higher vehicle traffic, and the one with lower noise pollution was located in a street with often congested traffic.

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Pires, Adriana. « Efeito da exposição ao material particulado (PM2,5) da poluição atmosférica na espermatogênese de duas gerações de camundongos ». Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/5/5144/tde-09122009-154418/.

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Este trabalho caracteriza os efeitos das condições reais de exposição ao material particulado urbano na espermatogênese por meio de análises histológicas de testículos de duas gerações de camundongos BALB/c durante o período gestacional, pósgestacional ou em ambos os momentos combinados. A geração parental foi exposta à poluição do ar em câmaras com ou sem filtros para PM2,5 (câmaras filtrada e não filtrada, respectivamente) por 4 meses, formando dois grupos: não exposto; e exposto. Estes animais foram acasalados e a freqüência do plug vaginal apresentou tendência de queda nas fêmeas expostas (p>0,05). O número de fêmeas prenhes também foi reduzido (p=0,007) e o número de nativivos foi menor na câmara não filtrada (186) quando comparada com a filtrada (268), contudo, o número de animais por ninhada não foi alterado (p>0,05). Após o acasalamento os machos foram eutanasiados, seus testículos pesados, fixados em solução de Bouin ou paraformaldeído 4% e corados com HE, PCNA, Ki67 ou TUNEL. Metade dos animais produzidos na primeira geração, constituída de animais de 1 dia de vida, foi transferida de uma câmara para outra formando os grupos pré-natal e pós-natal. Os animais remanescentes das câmaras filtrada e não filtrada constituíram os grupos não exposto e pré+pós-natal, respectivamente. Após 90 dias, os animais da primeira geração foram eutanasiados e seus testículos foram retirados, pesados, fixados e corados da mesma forma que sua geração parental. Os animais expostos ao PM2,5 da geração parental apresentaram aumento do peso dos testículos (p=0,002), dos epidídimos (p<0,001) e do peso relativo testículo/corpo (p=0,003), epidídimo/corpo (p=0,001). Não houve alteração no número de células germinativas e somáticas e nem na proliferação celular (p>0,05). A apoptose pela coloração de HE foi reduzida no estádio IV (p=0,046) e aumentada no estádio VIII (p=0,019) da espermatogênese. Pela técnica de TUNEL os estádios IV (p=0,017), V (p=0,035) e VIII (p=0,024) mostraram apoptose menor nos animais do grupo exposto. O estádio IV foi identificado como o de maior apoptose espontânea nas duas técnicas empregadas, HE (p<0,001); e TUNEL (p<0,001), entre os animais não expostos. O ciclo do epitélio seminífero foi alterado com freqüência reduzida do estádio IV entre os animais expostos (p=0,005). Os animais da primeira geração expostos no período pré-natal apresentaram redução de peso corpóreo (p<0,001) e dos testículos (p=0,012), bem como, aumento do peso relativo testículos/corpo (p=0,013). O número de células somáticas não foi alterado, mas o de espermatócitos nos grupos pós-natal (p=0,011) e pré+pós-natal foi aumentado (p=0,035) enquanto nos grupos pré-natal e pós-natal houve redução no número de espermátides alongadas (p<0,001). Não houve diferença significativa na taxa de proliferação, apoptose e freqüência dos estádios do ciclo do epitélio seminífero entre os grupos de exposição (p>0,05). O estádio IV mostrou-se o mais sensível para a ocorrência de apoptose espontânea nas duas técnicas empregadas: HE (p<0,001); e TUNEL (p<0,001). A freqüência normal dos estádios entre os animais não expostos mostrou que os estádios finais são os mais freqüentes (VI, VIII e VII, nesta ordem) e os iniciais os menos freqüentes (II e I, nesta ordem) para ambas as gerações. Estes resultados fornecem dados que sugerem que o PM2.5 da poluição atmosférica urbana é capaz de alterar o sistema reprodutivo masculino e a espermatogênese não dependendo do período da vida (durante ou após a gestação) em que os animais são expostos.
The present paper describes the effects of real exposure to urban PM2.5 on spermatogenesis by histological analysis of testes of mice (BALB/c) from two generations during fetal or postnatal phases of development and of mice exposed in both phases of development. Parental generations (BALB/c mice) were exposed to air pollution in chambers with or without filters for PM2.5 for 4 months (filtered and non-filtered chambers, respectively), forming two groups, namely non-exposed and exposed. These animals were mated and a frequency of decrease on vaginal plug in the exposed females was observed (p>0.05). The number of pregnant females was reduced as well (p=0.007) and the number of born alive decreased in the non-filtered chamber (186) when compared to the filtered chamber (268); however, the litter size was not altered (p>0.05). After mating, the male were killed, their testes were weighed and fixed in Bouins solution or 4% paraformaldehyde and stained in H&E, PCNA, Ki67 or TUNEL. Half of 1-day old offspring was crossed over between chambers forming the prenatal and postnatal groups; remaining offspring from filtered and non-filtered chambers comprised the non-exposed and pre+postnatally exposed groups, respectively. After 90 days, the animals from first generation were killed and their testes were removed, weighed, fixed and stained like the parental generation. The animals exposed to PM2.5 from the parental generation showed increased testis weight (p=0.002), epididymis weight (p<0.001), relative testis weight (p=0.003), and relative epididymis weight (p=0.001). The germ and somatic cells number was not reduced, and neither was cell proliferation (p>0.05). The apoptosis labeled by H&E was reduced in stage IV (p=0.046) and increased in stage VIII (p=0.019) of spermatogenesis. By using the TUNEL technique, stages IV (p=0.017), V (p=0.035) and VIII (p=0.024) showed fewer apoptosis in the exposed animal group. Stage IV was identified as the most spontaneous apoptosis in both methods: HE (p<0.001) and TUNEL (p<0.001), among the non-exposed animals. The cycle of the seminiferous epithelium was altered with reduced frequency of stage IV between the exposed animals (p=0.005). The animals from the first generation exposed during the prenatal period had a reduced body (p<0.001) and testis weight (p=0.012) and an increased relative testis weight (p=0.013). Differences in germ cell proliferation, apoptosis, and staging were not significantly different among treatment groups (p>0.05). Nevertheless, germ cell populations of post- (p=0.011) and pre+postnatally (p=0.035) PM-exposed animals contained an increased percentage of spermatocytes, while pre- and postnatal groups (p<0.001) had a reduced number of elongated spermatids. Stage IV was shown to be the most sensitive for the occurrence of spontaneous apoptosis in both methods used: H&E (p<0.001); and TUNEL (p<0.001). The normal frequency of the stages between non-exposed animals showed that the final stages are more frequent (VI, VIII e VII) and the beginning stages less frequent (II e I) to both generations. These results suggest that PM2.5 from urban air pollution is capable of altering the male reproductive system and spermatogenesis independently of the period of life when the animals are exposed to it (during or after pregnancy).

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Reis, Dayane Cristina Oliveira dos. « Caracterização dos íons majoritários do material particulado da atmosfera de Ribeirão Preto, uma cidade canavieira do estado de São Paulo ». Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/59/59138/tde-21102016-102025/.

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O material particulado (MP) presente na atmosfera tem papel importante na reflexão da luz solar, na visibilidade, no regime de chuvas e na saúde da população. As coletas de MP foram realizadas entre 2015 e 2016 na cidade de Ribeirão Preto (campus da USP), utilizando amostrador sequencial. Os íons majoritários solúveis para o material grosso e fino foram analisados por cromatografia de íons. As espécies predominantes na composição química do material particulado fino em ng m-3 (n=50) foram: SO42- (502 ± 306), K+ (149 ± 129) e NH4+ (135 ± 82), sendo estas principalmente derivadas da queima de biomassa. Na fração grossa, as espécies predominantes foram NO3- (216 ± 118), SO42- (146 ± 107), Ca2+ (123 ± 71), que estão correlacionadas à ressuspensão do solo, emissão veicular e absorção de ácido nítrico. Maiores massas de MP foram encontradas no período de safra da cana de açúcar, quando há maior queima de biomassa, maior ressuspensão do solo (devido ao intenso uso de maquinário), e menor quantidade de chuva. Houve um aumento significativo na concentração da maioria das espécies no período de safra da cana (período seco). No caso do material fino, as maiores concentrações de SO42- e NO3- foram observadas no período seco, durante o dia, demonstrando a importância da formação dessas espécies por reações fotoquímicas. Na fração grossa, a maior evidência de sazonalidade foi observada para os íons Ca2+, Mg2+ e K+ relacionados com uma maior ressuspensão do solo. O cálculo do balanço iônico mostrou que há um déficit de ânions, que pode estar relacionado ao fato dos íons HCO3-, CO32- e espécies aniônicas orgânicas, não terem sido quantificadas. A razão entre formiato e acetato (F/A) na fração fina foi de 1,7 ± 1,1 (n=40), demonstrando que a formação secundária de ácido fórmico é predominante em relação a emissão direta dos ácidos. A análise exploratória estatística mostrou que no caso da fração fina, a fonte de emissão de maior relevância é a queima de biomassa no período seco/safra. A ressuspensão do solo foi a principal fonte de emissão da fração grossa principalmente no período seco. Este trabalho demonstrou que as concentrações de todas as espécies analisadas no MP, com exceção do íon amônio na fração grossa, tiveram uma diminuição significativa com relação àquelas obtidas para amostras de MP coletadas em Araraquara, há cerca de 15 anos. Em comparação com trabalhos mais recentes em Araraquara, também foi observada uma diminuição na concentração de cálcio e magnésio na fração grossa, e de todas as espécies na fração fina.
Atmospheric particulate matter (PM) has an important role in the reflection of solar radiation, visibility, rainfall pattern and in the human health. PM samples were collected between 2015 and 2016 at the University of São Paulo campus in the city of Ribeirão Preto, using a sequential sampler. Soluble major ions from coarse and fine fractions were determined by ion chromatography. Predominant species in the chemical composition of fine MP in ng m-3 were (n= 50): SO42- (502 ± 306), K+ (149 ± 129) and NH4+ (135 ± 82), being mainly derived from biomass burning. Predominant species in the course fraction were: NO3- (216 ± 118), SO43- (146 ± 107) and Ca2+ (123 ± 71), being correlated with soil dust resuspension, vehicular emission and nitric acid adsorption. Higher mass of PM was found in the harvest period of sugar cane, when there is still partial burning of the leaves, high soil dust resuspension (due to intense use of agricultural machinery), and less amount of rain. There was a significant increase in the concentration of most species in the sugarcane harvest period. In the case of fine PM, the highest SO42- and NO3- concentrations were observed during the day and in the harvest period, demonstrating the importance of the formation of these species by photochemical reactions. In the case of coarse fraction, the greatest evidence of seasonality was observed for Ca2+, Mg2+ and K+ ions, related to higher soil dust resuspension. The calculation of ionic balance showed that there is a deficit of anions, which may be related to the fact of HCO3-, CO32- ions and organic anionic species have not been quantified. The ratio of formate and acetate (F/A) on the fine fraction was 1.7 ± 1.1 (n=40), demonstrating that the secondary formation of formic acid is predominant over the direct emission of the acids. The statistical exploratory analysis showed that in the case of fine fraction, the emission source of greater relevance in the harvest is the biomass burning, while the photochemical reactions are the major source in the non-harvest period. Soil dust resuspension was the primary source of emission of coarse fraction during the whole year. This study showed that the concentrations of all species analyzed in the PM (except for ammonium ions in the coarse fraction), had a significant decrease compared with those obtained for PM samples collected in Araraquara city, about 15 years ago. In comparison to more recent work in Araraquara it was also observed a decrease in the concentration of calcium and magnesium in the coarse fraction, and all species in the fine fraction.

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Lui, Elaine Schornobay. « Previsão de material particulado a curto e médio prazos com o uso de redes neurais artificiais ». Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-30032017-163007/.

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A preocupação com a qualidade do ar é crescente. Nos últimos anos, as emissões industriais e veiculares acarretam em muitos casos, especialmente em áreas urbanas, condições inadequadas para a saúde da população. Diversos estudos relacionam aumento em internações hospitalares, especialmente por problemas respiratórios, durante episódios de altas concentrações de material particulado. O objetivo deste estudo foi coletar dados diários de concentração de MP10 e compará-los com uma série de dados de quase 10 anos de coleta disponíveis para a cidade de São Carlos-SP. Além disso, ambas as séries de dados foram utilizadas para criar modelos de previsão da concentração de material particulado utilizando como ferramenta as redes neurais artificiais. O local escolhido para aquisição dos dados foi a Praça Voluntários da Pátria, no centro de São Carlos, em função da grande circulação de pessoas e veículos. As duas séries de dados foram coletadas com um equipamento amostrador de grande volume (AGV-MP10). A série 1 (1997-2006) foi obtida para caracterizar o MP de São Carlos. As coletas eram realizadas alternando-se os dias na semana. Para a série 2 (2014-2015) foram realizadas coletas diárias, com o mesmo equipamento e no mesmo local de amostragem da série 1. Para a criação dos modelos de previsão foram utilizados dados do Banco de Dados Meteorológicos para Ensino e Pesquisa (BDMEP) do Instituto Nacional de Meteorologia (INMET), de temperatura (°C), umidade relativa (%), velocidade do vento (m/s) e o acumulado de precipitação (mm). Os modelos foram desenvolvidos no softwareMatLab, utilizando duas arquiteturas de redes neurais, uma do tipo MLP (Multilayer Percetron) e outra do tipo NARX (nonlinear autoregressive network with exogenous inputs). Comparando os dados de MP10 da série 1 e da série 2, foi observado que houve uma redução nos índices de concentração de MP10 ao longo do tempo. Isto se deve à implantação de leis mais rigorosas e o desenvolvimento de tecnologias menos poluentes. Em relação aos modelos de previsão, para os dados da série 1, a utilização do modelo para previsão de médias mensais de concentração de MP10 foi mais eficiente do que o modelo para previsão de médias diárias, ambos tiveram como neurônios de entrada apenas variáveis climáticas, compostas de médias diárias e médias mensais, respectivamente. Para a previsão da série 2, o modelo utilizando a rede neural NARX, que utilizou como neurônios de entrada as variáveis climáticas e o MP10 do dia anterior, apresentou o maior erro absoluto médio (7,13), no entanto, o modelo NARX apresentou a convergência mais rápida. O menor erro absoluto (6,00) foi obtido pelo modelo em que foi utilizada a rede do tipo MLP, que apresentava como neurônios de entrada as médias diárias das variáveis climáticas e da concentração de MP10 do dia anterior. A rede MLP também foi utilizada para criação de um modelo em que apenas as variáveis climáticas eram utilizadas, para este modelo foi encontrado o valor de 6,52 como erro absoluto. A apresentação do dado de concentração de MP10 do dia anterior torna o desempenho dos modelos de previsão mais eficiente.
Concern about air quality is growing. In recent years, industrial and vehicular emissions have in many cases, especially in urban areas, resulted in inadequate conditions for the health of the population. Several studies have reported an increase in hospital admissions, especially due to respiratory problems, during episodes of high concentrations of particulate matter. The objective of this study was to collect daily PM10 concentration data and compare them with a series of data of almost 10 years of collection available for the city of São Carlos-SP. In addition, both sets of data were used to create forecasting models of the concentration of particulate material using artificial neural networks as a tool. The place chosen for data collect was Praça Voluntários da Pátria, in the center of São Carlos, due to the great circulation of people and vehicles. The two data series were collected with a high volume air sampler. The series 1 (1997-2006) was obtained to characterize the PM of São Carlos. The collections were carried out alternating the days in the week. For the series 2 (2014-2015) daily collections were carried out with the same equipment and in the same sampling site of the series 1. For the creation of the forecast models we used data from the Banco de Dados Meteorológicos para Ensino e Pesquisa (BDMEP) do do Instituto Nacional de Meteorologia (INMET), de temperature (°C), relative humidity (%), wind speed (m/s) and precipitation (mm). The models were developed in the MatLab software, using two neural network architectures, one of the MLP (Multilayer Percetron) type and another of the NARX (nonlinear autoregressive network with exogenous inputs) type. Comparing PM10 data from series 1 and series 2, it was observed that there was a reduction in PM10 concentration indices over time. This is due to the implementation of stricter laws and the development of cleaner technologies. In relation to the prediction models, for the data of the series 1, the use of the model to predict monthly means of concentration of PM10 was more efficient than the model for prediction of daily means, both had as input neurons only climatic variables, daily averages and monthly averages, respectively. For the prediction of series 2, the model using the NARX neural network, which used as input neurons the climatic variables and PM10 of the previous day, presented the highest mean absolute error (7,13), however, the NARX model presented the better convergence. The lowest absolute error (6.00) was obtained by the model in which the MLP type network was used, which presented as input neurons the daily averages of the climatic variables and PM10 concentration of the previous day. The MLP network was also used to create a model in which only the climatic variables were used, for this model was found the value of 6.52 as absolute error. Presenting an PM10 concentration data from the previous day improves the performance of forecast models.

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Schornobay, Elaine. « Caracterização de ambientes internos da região central de São Carlos/SP : material particulado e poluição sonora ». Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-30082012-145027/.

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Este trabalho teve como objetivo avaliar a qualidade ambiental interna de lojas da região central na cidade de São Carlos/SP. Foram monitorados os seguintes parâmetros: concentração e análise química de MP10 e de MP2,5, \'CO IND.2\', níveis de ruído, temperatura e umidade relativa do ar. A coleta de dados foi realizada de maneira simultânea em ambientes internos e externos de quatro lojas do centro da cidade por um período de oito horas diárias, das 9 h às 17 h. Dois pontos estavam localizados de frente para vias de grande circulação de veículos e dois no calçadão da cidade (sem trânsito de veículos). Os valores de concentração, tanto de MP10 como de MP2,5, se apresentaram, na maior parte dos dias de coleta, com os valores internos superiores aos externos. Para o período chuvoso, em que foi realizado o maior número de coletas, os valores de concentração não ultrapassaram os limites estabelecidos pela OMS, de 25 \'mü\'g/\'M POT.3\' para o MP2,5 e de 50 \'mü\'g/\'M POT.3\' para o MP10. Quanto à análise química, foi observado que não há diferenças significativas entre os ambientes interno e externo. Sendo que, em ambos os ambientes, foram encontrados Si, S, Ca, Fe, Al, K e Cu, elementos comumente observados em áreas urbanas. Em relação ao \'CO IND.2\', o seu monitoramento não se mostrou relevante, já que todos os ambientes monitorados realizavam trocas de ar com o ambiente externo de forma natural, dessa forma a concentração não atingiu valores preocupantes. Os níveis de poluição sonora monitorados no ambiente externo foram superiores aos do ambiente interno em todos os dias monitorados. Os pontos de monitoramento que ficavam direcionados para as vias de circulação de veículos apresentaram valores superiores aos encontrados no calçadão da cidade. Em todos os dias monitorados, os valores de ruído dos ambientes interno e externo não apresentaram acordo com o padrão estabelecido pela NBR 10.151/2.000, de 50 dB(A) e 60 dB(A), respectivamente. Sendo que os valores externos ficaram entre 61 dB(A) e 66,8 dB(A) e, para o ambiente interno, os valores variaram de 53,9 dB(A) a 63,6 dB(A). A temperatura e a umidade relativa do ar apresentaram variações ao longo do dia e, de acordo com a RE/ANVISA nº 09/2003 e o índice HI, a maioria dos dias monitorados sugere sensação de desconforto térmico aos ocupantes desses locais.
This study aimed to evaluate the indoor environmental quality of shops in the central region in São Carlos/SP. The following parameters were monitored: the concentration and chemical analysis of MP10 and MP2,5, \'CO IND.2\', noise levels, temperature and relative humidity. Data collection was performed simultaneously in internal and eternal environments of four stores in the center of town for period of eight hours daily, from 9 am to 5 pm. Two points were located in front of large circulation routes for vehicles and two on the sidewalk of the city (no vehicle traffic). The values concentration both PM10 and PM2,5 are presented, in most days of collection, with the internal values higher than the outside. For the rainy season, which was held in the greatest number of samples, the concentration values did not exceed the limits set by OMS of 25 \'mü\'g/\'M POT.3\' for MP2,5 and 50 \'mü\'g/\'M POT.3\' for MP10. In the chemical analyses, it was not observed significant differences between the internal and external environments, since in both environments were found Si, S, Ca, Fe, Al, Cu and K, elements commonly seen in urban areas. In relation to the \'CO IND.2\' monitoring was not relevant, since all monitored environments performed ais exchanges with the external environment in a natural way, producing values concentration not concern. The noise levels monitored in the external environment were superior to the internal environment every day. The monitoring points directed to the traffic routes of vehicles had higher values than those found on the sidewalk of the city. On each day the monitored noise vaues of the internal and external environments not presented inside of the standard established by NRB 10.151/2000 of 50 dB(A) e 60 dB(A), respectively, since external values were between 61 dB(A) and 66,8 dB(A), and the internal environment values ranged from 53,9 dB(A) and 63,6 dB(A). The temperature and relative humidity showed variations thoughout the day, and according to RE/ANVISA nº 09/2003 and the index HI, most of the days monitored suggests thermal discomfort to the occupants of these places.

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Backes, Audrey Ann. « Evaluation of Particulate Matter Inside Control Rooms at a Quarry and Processing Facility ». University of Toledo Health Science Campus / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=mco1418321178.

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Rotiroti, Arthur Sanches. « Monitoramento da qualidade ambiental no mercado municipal da cidade de São Carlos, SP : material particulado em suspensão, temperatura, umidade e ruído ». Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-03102013-114129/.

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Este trabalho apresenta uma caracterização ambiental do Mercado Municipal da cidade de São Carlos-SP, localizado na região central da cidade, onde ocorre grande movimentação de pessoas e veículos, em horário comercial. Foram analisados os níveis de material particulado em suspensão no ar, nas suas frações MP10 e MP2,5, níveis de ruído, temperatura e umidade relativa do ar relativa, nos ambientes internos e externos do Mercado. Os valores das concentrações de material particulado, tanto para MP10, como MP2,5, apresentaram-se, em geral, maiores no ambiente interno do que no externo. Os valores encontrados para MP2,5 chegaram a 66,60 g/m³, no ambiente interno, e 60,56 g/m³, no externo. Para a fração MP10, a concentração interna alcançou o valor de 117,74 g/m³ e a externa atingiu os 134,51 g/m³. Duas metodologias diferentes foram utilizadas para a determinação da concentração de material particulado em suspensão, a gravimetria pelo Personal Enviromental Monitor (PEM), e a fotometria por espalhamento de luz pelo aparelho ADR-1500 e pDR-1500. A técnica da gravimetria apresentou, em geral, os valores mais elevados. Uma análise do material particulado foi realizada, por meio da técnica de Fluorescência de Raio-X, para identificação dos elementos químicos presentes. Foram encontrados: Ba, Ca, K, Zn, S, Fe, e Rb. Já em relação à temperatura e umidade relativa do ar, os níveis oscilaram bastante durante o dia, com médias da temperatura interna entre 14°C e 34°C, e a umidade com valores entre 19% e 58%. Foi calculado o Índice de Calor (Hi - Heat Index), revelando desconforto térmico na maior parte dos dias, com as temperaturas internas normalmente acima das externas. Os níveis de ruído encontrados no ambiente interno e externo chegaram a 71,42 e 85,43 dB(A), respectivamente. Foi aplicado um questionário sobre qualidade ambiental aos funcionários do Mercado: 67% dos respondentes acham o local muito quente e 33 % consideram o local muito ruidoso.
This study presents an environmental characterization of the Municipal Market in the city of São Carlos, SP, located at the downtown area, where there is a great movement of people and vehicles, mainly during business hours. The levels of suspended particulate matter in the air were analyzed, in its fractions PM10 and PM2,5, noise levels, temperature and relative humidity in indoor and outdoor environments of the Market. The concentrations of the particulate material for both MP10 and PM2,5, are presented in general higher in the internal environment than the outer and exceeded the limits of the World Health Organization-WHO. The values for PM2,5 reached to 66,60 g/m³, the internal environment, and 60,56 g/m³, externally. For PM10 fraction, the internal concentration reached a value of 117,74 g/m³ and external reached 134,51 g/m³. Two different methods were used to determine the concentration of suspended particulate matter, gravimetry by The Environmental Monitor-PEM and light scattering photometric by the device ADR-1500 and pDR-1500. The gravimetric technique showed in general the highest values. An analysis of the particulate matter was performed by the technique of X-ray fluorescence for the identification of chemical elements. Were found: Ba, Ca, K, Zn, Fe and Rb. In relation to temperature and relative humidity, levels oscillated during the day, with average of the internal temperature between 14°C and 34°C, and humidity with values between 19% and 58%. Were calculated the Heat Index (Hi), revealing thermal discomfort in most of the days, with internal temperatures usually above the external. The noise levels in the internal and external environment reached 71,42 and 85,43 dB(A), respectively. A questionnaire about the environmental quality was applied on the officials Market: 67% of respondents thought the place was very hot and 33% considered the place very noisy.

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Emygdio, Ana Paula Mendes. « Identificação de bioaerossóis de origem fúngica na cidade de SãoPaulo ». Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/100/100136/tde-22042016-190752/.

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Há poucos estudos relacionados com a caracterização dos componentes biológicos presentes no material particulado atmosférico, chamados bioaerossóis. Esses componentes biológicos podem assumir uma relação direta com a deflagração de doenças e também estão relacionados com os processos climáticos, em especial como núcleos de formação de gelo. Dentre os bioaerossóis, foram estudados, neste trabalho, os fungos anemófilos, sendo os principais os Basidiomycota, Ascomycota e os Fungos mitospóricos. O objetivo desse trabalho foi estimar a contribuição dos aerossóis fúngicos para a composição biogênica do material particulado atmosférico da Região Metropolitana de São Paulo. Foram realizadas medidas em dois sítios: na Cidade Universitária e no Pico do Jaguará. Para isso, foram caracterizados os tipos fúngicos utilizando-se um microscópio ótico e estimada a massa dos aerossóis de origem fúngica utilizando-se biomarcadores. Foram realizadas coletas durante 2013, 2014 e 2015 com o amostrador Burkard 7-day Recording Sampler, sendo que em 2015 também foram realizadas coletas com filtros de quartzo com o amostrador Airmetrics MiniVol portable Sampler. Foram identificados e obtida a concentração dos tipos fúngicos observados na atmosfera da RMSP, sendo encontrados 39 grupos principais de fungos, sendo os principais os Basidiomycotas. A concentração média total foi de 5736 (± 2459) esporos/m³ por dia. Os Ascomycota, Basidiomycota e os fungos mitospóricos se correlacionaram com as variáveis meteorológicas de forma diferente. Observou-se variação da concentração de esporos durante os diferentes períodos do dia, sendo que a maior concentração de esporos ocorreu na madrugada, possivelmente devido às condições meteorológicas (elevada umidade e temperaturas mais amenas), contudo a concentração dos fungos mitospóricos foi maior durante o período da tarde, principalmente devido aos mecanismos de liberação de esporos. No verão e na primavera foram obtidas as maiores concentrações de Ascósporos e Basidiósporos e no inverno e outono foram obtidas as maiores concentrações dos fungos mitospóricos. Além disso, observou-se uma correlação positiva e significativa entre a concentração de esporos totais e o material particulado inalável (MP10), indicando que ambos são influenciados da mesma forma pelas variáveis meteorológicas e/ou tem uma fonte em comum, como por exemplo a ressuspensão da poeira do solo. O Arabitol, Manitol, Treitol e os esporos de fungos são positivamente correlacionados, indicando que os três açucares podem ser traçadores de esporos de fungos na atmosfera. Utilizando-se um fator de conversão proposto na literatura foi possível estimar que 2% da concentração do MP10 e 8% da concentração do OC estão associados aos esporos de fungos, indicando a importância dos esporos fúngicos. Com o uso de modelos receptores foram observadas 6 fontes para o MP10: queima de biomassa resultante de processos industriais; queima de biomassa resultante da queima da vegetação; aerossóis fúngicos; formação de aerossol secundário; ressuspensão do solo e emissão veicular. Esses resultados constituem um avanço para a pesquisa em bioaerossóis no Brasil, já que muitas dessas análises ainda não haviam sido realizadas em áreas urbanas no Brasil
Although the biogenic components of Particulate Matter (PM) can have a direct relationship with the outbreak of respiratory diseases and can be linked to changes in climate processes there are very few studies related to its characterization in the atmospheric aerosols. Among the bioaerosols, the airborne fungi were studied, and the Basidiomycota, Ascomycota and Mitosporic fungi were the main characterized. The goal of this work was to estimate the contribution of the fungal aerosol to the RMSP atmosphere, with samplings in two sites: Cidade universitária (USP) and Pico do Jaraguá (PJ). For that, the fungi types were characterized using an optical microscope and it was estimated the mass of the fungal aerosol using biomarkers. Sampling was carried out during 2013, 2014 and 2015 with the \"Burkard 7-day Recording Sampler\", and in 2015, filters were sampled with the \"Airmetrics MiniVol portable Sampler. It was identified and determined the concentration of the fungi types observed in the RMSP atmosphere, and were found 39 main groups of fungi. The main group was the Basidiomycota. The mean concentration of the total fungi was 5736 (± 2459) spores/m³ per day. The Ascomycota, Basidiomycota and the mitosporic fungi correlated in different ways with the meteorological variables. A variation of the spores concentration during different times of the day was observed, with the occurrence of the highest concentration of spores at dawn, possibly due to weather conditions (high humidity and cooler temperatures), but the concentration of the mitosporic fungi was higher during the afternoon, mainly due to the spores release mechanisms. In the summer and spring were observed higher concentrations of Ascospores and Basidiospores and in the autumn and winter were obtained higher concentration of Mitospores. Besides that, it was also observed a positive and significant correlation between the fungal spore with the particulate matter, indicating that both are influenced in the same way by weather variables and/or has a common source such as soil resuspension. Arabitol, Mannitol, Threitol and the fungi spores are positive correlated, indicating that these three sugar alcohols can be a tracer for fungi spores in the atmosphere. Using the conversion factor proposed in the literature was possible to estimate that 2% of the PM10 concentration and 8% of the OC concentration it is due to fungi spores, indicating its importance. Using receptor modeling it was identified six sources for PM10, the biomass burning resulting from industrial processes, the biomass burning resulting from vegetation burning, the fungal aerosol, the secondary formation aerosol, the soil resuspension and vehicular emission. These results are a breakthrough for research on bioaerosols in Brazil, since many of this analyzes had never been performed in urban areas in Brazil

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Estapa, Margaret L. « Photochemical Reactions of Particulate Organic Matter ». Fogler Library, University of Maine, 2011. http://www.library.umaine.edu/theses/pdf/EstapaM2011.pdf.

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Holstius, David. « Monitoring Particulate Matter with Commodity Hardware ». Thesis, University of California, Berkeley, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3640465.

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Health effects attributed to outdoor fine particulate matter (PM_2.5) rank it among the risk factors with the highest health burdens in the world, annually accounting for over 3.2 million premature deaths and over 76 million lost disability-adjusted life years. Existing PM_2.5 monitoring infrastructure cannot, however, be used to resolve variations in ambient PM_2.5 concentrations with adequate spatial and temporal density, or with adequate coverage of human time-activity patterns, such that the needs of modern exposure science and control can be met. Small, inexpensive, and portable devices, relying on newly available off-the-shelf sensors, may facilitate the creation of PM_2.5 datasets with improved resolution and coverage, especially if many such devices can be deployed concurrently with low system cost.

Datasets generated with such technology could be used to overcome many important problems associated with exposure misclassification in air pollution epidemiology. Chapter 2 presents an epidemiological study of PM_2.5 that used data from ambient monitoring stations in the Los Angeles basin to observe a decrease of 6.1 g (95% CI: 3.5, 8.7) in population mean birthweight following in utero exposure to the Southern California wildfires of 2003, but was otherwise limited by the sparsity of the empirical basis for exposure assessment. Chapter 3 demonstrates technical potential for remedying PM_2.5 monitoring deficiencies, beginning with the generation of low-cost yet useful estimates of hourly and daily PM_2.5 concentrations at a regulatory monitoring site. The context (an urban neighborhood proximate to a major goods-movement corridor) and the method (an off-the-shelf sensor costing approximately USD $10, combined with other low-cost, open-source, readily available hardware) were selected to have special significance among researchers and practitioners affiliated with contemporary communities of practice in public health and citizen science. As operationalized by correlation with 1h data from a Federal Equivalent Method (FEM) β-attenuation data, prototype instruments performed as well as commercially available equipment costing considerably more, and as well as another reference instrument under similar conditions at the same timescale (R² = 0.6). Correlations were stronger when 24 h integrating times were used instead (R² = 0.72).

Chapter 4 replicates and extends the results of Chapter 3, showing that similar calibrations may be reasonably exchangeable between near-roadway and background monitoring sites. Chapter 4 also employs triplicate sensors to obtain data consistent with near-field (< 50 m) observations of plumes from a major highway (I-880). At 1 minute timescales, maximum PM_2.5 concentrations on the order of 100 μg m^–3 to 200 μg m^–3 were observed, commensurate with the magnitude of plumes from wildfires on longer timescales, as well as the magnitude of plumes that might be expected near other major highways on the same timescale. Finally, Chapter 4 quantifies variance among calibration parameters for a large sample of the sensors, as well as the error associated with the remote transfer of calibrations between two sufficiently large sets (± 10 % for n = 12). These findings suggest that datasets generated with similar sensors could also improve upstream scientific understandings of fluxes resulting from indoor and outdoor emissions, atmospheric transformations, and transport, and may also facilitate timely and empirical verification of interventions to reduce emissions and exposures, in many important contexts (e.g., the provision of improved cookstoves; congestion pricing; mitigation policies attached to infill development; etc.). They also demonstrate that calibrations against continuous reference monitoring equipment could be remotely transferred, within practical tolerances, to reasonably sized and adequately resourced participatory monitoring campaigns, with minimal risk of disruption to existing monitoring infrastructure (i.e., established monitoring sites). Given a collaborator with a short window of access to a reference monitoring site, this would overcome a nominally important barrier associated with non-gravimetric, in-situ calibration of continuous PM_2.5 monitors. Progressive and disruptive prospects linked to a proliferation of comparable sensing technologies based on commodity hardware are discussed in Chapter 5.

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Healey, Katherine. « The genotoxicity of urban particulate matter ». Thesis, University of Leeds, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.422089.

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Vincent, Keith John. « Atmospheric particulate matter and historic buildings ». Thesis, Middlesex University, 1993. http://eprints.mdx.ac.uk/13435/.

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Atmospheric particulate matter, along with gaseous and precipitation pollutants, were collected close to three historic buildings; Lincoln Cathedral, Bolsover Castle and Wells Cathedral, in order to estimate the amount of sulphur and nitrogen deposited onto each. Results obtained showed that the gaseous dry deposition of both sulphur and nitrogen was the main deposition pathway at Lincoln and Bolsover, whereas as a result of high precipitation amounts the wet deposition pathway was the most significant at Wells. At each sampling site the amount of sulphur and nitrogen deposited as dry particulate matter was relatively insignificant. Estimated washout values for both SO² and SO²⁻, indicated that the former provided approximately 80% of the sulphur in precipitation arriving at the building surfaces. The important role of the gas was reinforced by the significant correlation between the sulphur level in precipitation and sulphur dioxide. The concentration of sulphur in precipitation was found to decrease at high precipitation volumes, whereas the nitrogen concentration was unaffected by precipitation volume. A high sulphate to sulphur dioxide concentration ratio during the summer months was indicative of photochemical oxidation processes. Conversely, during the winter months the relatively low sulphate to sulphur dioxide concentration ratio suggested that sulphate and sulphur dioxide were released from common sources. Multivariate statistical techniques, comprising principal component analysis and multiple regression analysis, were used to infer characteristics about the origin of the constituent parts of the collected particulate matter. In general, three sources of material; secondarily formed particulate matter, sea-salt and crustal material, were estimated to contribute to the collected particulate matter.

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Jurinski, Joseph Bernard Jr. « Geochemical Investigations of Respirable Particulate Matter ». Diss., Virginia Tech, 1998. http://hdl.handle.net/10919/30632.

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Over the course of our lives we are exposed to airborne particulate matter in the workplace, home, and environment that results in the deposition of millions of particles in the lung. These exposures may result in disease if they are significant enough. The potential for harmful exposure depends in part on the dust's biodurability and the bioavailability of harmful constituents derived from the particles. A mixed flow reactor was used to evaluate two applications of geochemical methods to characterize the behavior of inhaled particles in the body. Dissolution rates of a well-characterized sample of powdered talc were measured in solvents that mimic fluids found in the human lung. These studies showed that variation of solvent chemistry, including the addition of organic chelators and proteins at intercellular fluid concentrations, does not markedly affect the measured dissolution rate of talc at 37 degrees Celcius and the data further indicate that the dissolution mechanism for talc in aqueous solutions is independent of pH over a range of pH from 2 to 8. The dissolution rate, determined by measuring the silicon release rate per unit surface area of talc is 1.4 (+/- 1.0) x 10-11 mol Si/(m2 -sec). A geometric shrinking particle model using this dissolution rate predicts an estimated lifetime (upper limit) of approximately 8 years for a 1 micron talc particle under pulmonary conditions. Talc dissolves considerably faster than quartz, but slower than chrysotile and olivine in the body. These data can be used to place constraints on the role of particle dissolution in the disease models associated with airborne respirable particulate matter. Secondly, the bioavailability of As and Cr was determined from a sample of coal fly ash from an eastern U.S. power plant. The time-release profiles of As and Cr were determined for these materials in physiologically-based solvents and incorporated into a toxicokinetic model to predict the exposure potential to As and Cr from occupational exposures to the coal fly ash. Predicted occupational exposure contributions from the ash relative to total environmental exposures were insignificant. The exposure predicted from the geochemical approach was compared with results observed in a cohort occupationally exposed to coal fly ash and found to be within one order of magnitude of the response of the occupational cohort. These results support the application of geochemical techniques to evaluate exposures to complex respirable materials.
Ph. D.

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Farnoud, Ali. « Electrostatic removal of diesel particulate matter ». Ann Arbor, Mich. : ProQuest, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3303839.

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Thesis (Ph.D. in Civil Engineering)--S.M.U.
Title from PDF title page (viewed Mar. 16, 2009). Source: Dissertation Abstracts International, Volume: 69-03, Section: B, page: 1799. Adviser: Alfredo Armendariz. Includes bibliographical references.

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Hammonds, Mark David. « Characterisation of carbonaceous particulate matter in Edinburgh ». Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/6236.

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Airborne particulate matter (PM) has important harmful effects on human health, as well as a number of other important atmospheric effects. Although progress has been made in understanding the sources and effects of PM, there remains considerable uncertainty on a number of issues, including the nature of a lot of the carbonaceous material, which comprises 30{50% on average of PM mass. This project aims to compare different methods of PM measurement, and contribute understanding to the nature and origin of the carbonaceous fraction of PM. Daily samples of PM10 were collected from three sites in the Edinburgh area using Partisol-Plus 2025 Sequential Air Samplers: 1) Urban Background (20 August 2008 until 21 April 2010); 2) Rural (25 February 2009 until 21 April 2009); and 3) Roadside (10 September 2009 until 21 April 2010). These localities provided PM that was, respectively, representative of: 1) city-wide background air; 2) air at a location distanced from population centres, roads and industrial areas; and 3) air influenced by the emissions associated with traffic. Gravimetric PM10 concentration (µgm-3) was determined for each daily filter sample, after a blank correction to compensate for the relative humidity (RH)-influenced change in filter mass over time. The correction was successful, with good agreement attained between the Partisol and a PM10 Tapered Element Oscillating Microbalance Filter Dynamics Measurement System (TEOM-FDMS) co-located at the Urban Background site. The general levels of PM10 measured in this monitoring campaign indicate that the air in Edinburgh was relatively clean. The main factor causing exceedance of the daily European Union (EU) limit value was shown to be transport of PM10 from areas of mainland Europe. High PM10 concentrations were also strongly associated with calm weather conditions in Edinburgh, which allowed the build-up of particulate pollution over time. Aethalometer-equivalent daily concentrations of black carbon (BC) were determined by measuring the optical reflectance of the PM10 filters from the Partisol samplers. The conversion of reflectance values to BC concentrations relied on a number of correction factors, which may have impacted on the accuracy of the results with time and location. The concentration of BC in Edinburgh was shown to be relatively low, with the daily variation being controlled by local emissions and meteorology. BC as a proportion of PM10 increased with sampling location in the order: Rural < Urban Background < Roadside. Predominantly traffic-related BC concentrations increased during periods of low wind speed and were not greatly influenced by long-range transport of aerosol. Daily water-soluble organic matter (WSOM) concentrations were obtained by aqueous extraction of the filter samples and measurement of the dissolved organic carbon (DOC). About 11% on average of the Edinburgh PM10 was WSOM. The majority of this WSOM seemed to have originated from air masses outside of the city, although there was a minor contribution from urban traffic sources. A solid phase extraction (SPE) procedure was used to isolate about one-third of the WSOM as hydrophobic compounds and this revealed a relative increase in the amount of less oxygenated material from traffic sources. Higher than average WSOM concentrations were strongly associated with calm weather conditions that allowed the transient build-up of particle concentrations. Some of the peaks in WSOM concentration were related to the transport of air masses from areas of mainland Europe where biogenic secondary organic aerosol (SOA) and biomass burning were likely sources. Analysis of the WSOM samples by UV-Vis absorption spectroscopy showed clear seasonal trends in the composition of hydrophobic watersoluble organic matter (HWSOM), interpreted as predominance of lower molecular weight aliphatic compounds in summer but predominance of larger aromatic and polyconjugated compounds in winter. Raman spectra were obtained for different carbonaceous reference materials. The results of curve fitting for these spectra gave D1 band full width at half maximum (FWHM) values that distinguished between diesel exhaust particles from a local bus and a humic acid sample. Analysis of Edinburgh PM10 samples using Raman microspectroscopy (RM) showed a variation in the structural order of the carbon compounds present between that of soot and HUmic-LIke Substances (HULIS), with a tendency towards more soot-like material being present. There was no strong relationship between carbonaceous order and BC concentration, showing that coloured organic compounds have the potential to influence reflectance measurements. The combination of these measurement approaches has yielded insights into the nature and variation in carbonaceous PM material with time and sampling location.

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Alemany, Adair Aparecida Santos. « Influência da dieta hipercolesterolêmica em camundongos knock-out LDLr -/- expostos as partículas ambientais concentradas sobre o sistema pulmonar ». Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-25092013-151131/.

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Introdução: Os dados epidemiológicos e experimentais têm mostrado efeitos adversos da exposição pré e pós natal ao material particulado (MP2,5) sobre a saúde fetal e adulto. Entretanto, poucos estudos abordaram a toxicidade fetal da exposição gestacional à poluição do ar ambiental, bem como efeitos a longo prazo de adversos da exposição pré-natal sobre o desenvolvimento pós-natal e maturação de vários sistemas de órgãos. Objetivos: O objetivo deste estudo foi determinar se a exposição pré-natal e / ou pós-natal ao material particulado, influencia o desenvolvimento pulmonar e resposta vascular pulmonar em um modelo de camundongo suscetível a aterosclerose (LDLr-/- camundongos knockout). Métodos: Camundongos LDLr-/- foram expostos durante a gestação ao ar filtrado (AF) ou ar poluído (AC). Após o período de desmame, os filhotes foram subdivididos e novos quatro grupos foram formados de acordo com a exposição gestacional ou a exposição pós natal contínua no ar poluído. Atingindo a idade de 3 meses, esses grupos foram novamente subdivididos, formando um total de 8 grupos e uma dieta hipercolesterolêmica foi introduzida. Os seguintes parâmetros foram analisados: desfechos gestacionais, dosagem de colesterol total (CT) e triglicerídeos (TG) do fígado, avaliação de citocinas no LBA, e avaliação imunohistoquímica da resposta vascular pulmonar . Resultados: Nos grupos que receberam dieta hipercolesterolêmica (DH) os níveis de colesterol apresentaram-se aumentados (p=0,002); A expressão da IL6 no LBA mostrou-se elevada (p=0,01) somente no grupo que não foi exposto a poluição em nunhum período da vida e recebeu dieta postnatalmente. Diferenças significativas também foram observadas na expressão pulmonar vascular dos seguintes imunomarcadores: endotelina (p=0,05); ENOS (p=0,04); IL1? (p=0,005); INOS (p=0,002); ISOP (p=0,001); NOX2 (0,01) e ICAM (0,04) quando comparados ao grupo controle. O volume pulmonar total também se mostra alterado em decorrência do tratamento. Assim, conclui-se que a resposta do desenvolvimento pulmonar à exposição gestacional à poluição particulada do ar pode ser evidenciada mais tarde durante a vida adulta e agir como um fator modulador de insultos pós-natal devido à exposição a poluição do ar e a uma dieta hipercolesterolemica em individuos predispostos aterosclerose
Epidemiological and experimental data have shown adverse effects of gestational and post natal exposure to ambient particulate matter (PM) on the fetal and adult health. However, few studies addressed the fetal toxicity of gestational exposure to environmental air pollution as well as long-term adverse consequences of prenatal exposure on postnatal development and maturation of several organ systems. The aim of this study was to determine if prenatal and/or postnatal exposure to concentrated ambient particles influences lung development and pulmonary vascular response in an atherosclerosis susceptible mouse model (LDLr-/- knockout mice). LDLr-/- mice were exposed during the pregnancy to either filter (AF) or polluted air (CAP). After weaning period, pups were subdivided and new 4 groups formed according to gestational and continuous or not post natal exposure to air pollution. Reaching the age of 3 months these groups were again subdivided and a hypercholesterolemic (HC) diet introduced and a total of 8 groups were formed. Then the following parameters were analyzed: evaluation of the offspring outcomes, assessment of airway responsiveness, evaluation of cytokines in BALF, dosage of total cholesterol (TC) and triglycerides (TG) in the liver and pulmonary vascular response by immunohistochemistry. Results: Animals that received HC diet presented higher levels of cholesterol (p=0.002) when compared to those animals that received normal diet. Expression of IL-6 was only increased in the groups of mice exposed not exposed to particulate air pollution and that received the HC diet (p=0.01). Significant differences were also observed in vascular expression of immunomarkers in the lung endothelin (p=0.05); ENOS (p=0.04); IL1? (p=0.005); INOS (p=0.002); ISOP (p=0.001); NOX2 (0.01) e ICAM (0.04). Total lung volume was also different, there was an increase in those animals receiving a HC diet. In conclusion, the response of the lung development to gestational exposure to particulate air pollution can be evidenced later in life and act as a modulator factor for postnatal insults due to exposures to particulate air pollution and hypercholesterolemic diet in individual predisposed to atherosclerosis

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Bowsmer, Jason Paul. « Evaluation and development of numerical algorithms for multi component aerosol modelling in London ». Thesis, Imperial College London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272411.

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Ramires, Letícia Ogushi Romeiro. « Análise da fonte e composição da poluição atmosférica em diferentes locais da região metropolitana de São Paulo ». Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-27032013-094910/.

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Grandes cidades, como São Paulo, são afetadas de forma significante pela poluição atmosférica. É de grande importância a caracterização das fontes emissoras da poluição atmosférica, não somente nas regiões centrais, mas também nas regiões periféricas, pois a composição da poluição pode não ser homogênea em toda a extensão da cidade. Neste estudo foram caracterizados os componentes da poluição atmosférica em quatro regiões dentro cidade de São Paulo. Para este fim foram Coletados Material Particulado (PM2.5) durante vinte dias no período de inverno de 2011 e vinte dias durante o período de verão de 2011. O material foi coletado através de filtros de policarbonato com 24 h de exposição, e foi submetido a análises gravimétricas, determinação da concentração de Black Carbon por refletância e determinação da composição elementar por Fluorescência de Raios-X. A identificação das diferentes fontes geradoras de material particulado foi baseada na análise de Componentes Principais (ACP). A variação da concentração da massa do material particulado fino (PM2.5) em g/m3 não teve diferença significativa entre os locais amostrados, mas mostrou diferença entre as estações do ano, sendo maior no período do inverno em todos os locais. A proporção do Black Carbon teve um comportamento diferente da massa. O Black Carbon não variou significantemente entre as estações do ano, porém apresentou diferença entre os locais amostrados, destacando-se no Parque do Ibirapuera e na Zona Leste. Foram encontrados 3 Fatores que explicam 75% da variabilidade. O Fator 1 é constituído pelos elementos Ti, V, Mn, Fe, Ni, Pb, P, S Cr e K e foi atribuído como sendo associado à ressuspensão de solo e emissões veiculares, O Fator 2 é composto por V, P, BC, e S e foi interpretado como sendo representativo de emissões veiculares de combustíveis com alto teor de enxofre. O Fator 3 é 7 associado aos elementos BC e Ni e foi interpretado como sendo produzido por emissões veiculares em geral
Large cities such as São Paulo are significantly affected by air pollution. It is of great importance to characterize the emission sources of air pollution, not only in the central regions of the city of São Paulo, but also in peripheral regions, do to the fact that the composition of pollution may not be homogeneous across the city area. This study shows the Characterized the components of air pollution in four different areas of the metropolitan region of São Paulo. Particulate matter (PM 2.5) was collected during the winter of 2011 and summer of 2011. It was collected 24-h PM2.5 samples, employing gravimetry to determine PM2.5 mass concentrations; reflectance to quantify black carbon concentrations and X-ray fluorescence to characterize elemental composition. A receiver model based on principal component analysis (PCA) was used to identify the involvement of the different sources for the generation of particulate matter. The fine particulate matter (PM2.5) in g/m3 did not differ significantly among the locations. However, the results collected showed differences according the seasons evaluation, being higher in the winter for all regions sampled. The proportion of Black Carbon behaves differently than the mass. It does not vary significantly between the seasons, but between the different regions. The proportion of Black Carbon was higher in Ibirapuera Park and the East Zone. Was found 3 factors explaining 75% of the variability. Factor 1 consists of the elements Ti, V, Mn, Fe, Ni, Pb, P, S Cr e K and was related to crustal emission (soil) and vehicle emissions, Factors 2 consists of the elements V, P, BC, e S and can be related to vehicular emissions of fuels with high sulfur content. Factor 3 consists of the elements BC and Ni was associated to vehicle emission

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Navel, Simon. « Rôle des échanges à l’interface eau-sédiment et de l’activité des invertébrés sur la dégradation de la matière organique particulaire dans le milieu hyporhéique ». Thesis, Lyon 1, 2011. http://www.theses.fr/2011LYO10291.

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Les réseaux trophiques des cours d'eau de tête de bassin sont généralement dépendants d'apports extérieurs de matière organique particulaire (MOP), principalement des feuilles provenant des berges. Ces dernières sont dégradées par les effets conjoints de facteurs abiotiques (lessivage, abrasion, fragmentation physique) et d'un cortège d'organismes : bactéries, champignons et invertébrés. Une part importante des apports de MOP est enfouie dans la zone sédimentaire des cours d'eau (zone hyporhéique) dont les caractéristiques physiques influencent l'activité des microorganismes en contrôlant les conditions chimiques dans les sédiments et déterminent la distribution verticale des invertébrés benthiques. A l'heure actuelle, peu de travaux ont cherché à quantifier l'influence des interactions entre le milieu physique et les activités des organismes sur le processus de dégradation de la MOP enfouie dans le sédiment des cours d'eau. Dans ce contexte, cette thèse a pour but d'étudier le processus de dégradation de la MOP (sous forme de feuilles), et en particulier l'impact des caractéristiques sédimentaires sur la contribution des différentes communautés d'acteurs impliquées dans ce processus (microorganismes et invertébrés). Ma thèse a permis de montrer que la structure physique du milieu influence indirectement la dégradation en contrôlant l'accessibilité (taille des interstices) de la litière enfouie pour les déchiqueteurs, et dans une moindre mesure directement, quand les échanges avec la surface sont très fortement modifiés (colmatage). Les invertébrés déchiqueteurs peuvent accélérer directement la dégradation de la matière organique lorsque cette dernière est accessible. L'impact indirect des invertébrés est lié à leur capacité à remanier le sédiment (bioturbateur ou non) et modifier les conditions physicochimiques dans le sédiment
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Boswell, Colin R. « Atlanta automotive particulate matter exposure and evaluation ». Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34679.

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The following thesis titled, Atlanta Automotive Particulate Matter Exposure and Evaluation, presents data obtained as a part of a joint project with Emory University, Rollin's School of Public Health. The Atlanta Commuters Exposure (ACE) Study uses both real-time and time-integrated sampling techniques for ambient aerosol concentrations. The ACE study is unique in that it will correlate the ambient aerosol concentrations with the concurrent health measurements. The primary objective of this thesis is to measure the concentration, size distribution and the chemical composition of PM2.5 inside the vehicle cabin for several commuters. The vehicles followed a scripted route along roadways in the Atlanta metropolitan region during periods of peak traffic volume, while the compact air sampling package of both real-time and time-integrated instruments recorded data. Real-time measurements for Particulate Matter (PM) were made using compact Optical Particle Counters (OPC), a Condensation Particle Counter, and a MicroAethalometer. The time-integrated measurements for Elemental Carbon (EC), Organic Carbon (OC), Water Soluble Organic Carbon (WSOC), particulate elemental concentrations, and speciated organics required filter collection methods. Thus a compact air-sampling package was created to combine both sets of real-time and time-integrated instruments. The following results are presented for the first four commutes. The framework for analyzing and presenting results is developed, and will be used for future commutes.

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Patra, Aditya Kumar. « Particulate matter emission from paved road surfaces ». Thesis, Imperial College London, 2006. http://hdl.handle.net/10044/1/11860.

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Song, Wei Wei. « Personal exposure to particulate matter in buses ». Thesis, University of York, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.485138.

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Personal exposure levels to particles inside buses were investigated in two northern UK cities (Bradford and York). Mass concentrations of particles in two size fractions (PMlO and P~h.5) and number concentrations of particles 0.3 to 15 um were measured by using two real-time optical monitors. Factors which may result in high exposure to particles in different size classes were recorded and statistically analysed. In order to further numerical understanding of the concentrations of particles in buses, a three-dimensional computer model was developed from a previous indoor model. The model was used to simulate and predict particle concentrations in buses, based on empirically determined parameters, and compared with measured in-bus and out-bus particle concentrations. Personal exposures to particles were found to be higher than corresponding ambient roadside particle concentrations, as well as those measured in previous studies in other indoor microenvironments, such as homes and offices. PMlO and PM2.5 levels were higher in morning and evening rush hours, compared to off-peak periods. Statistical analysis indicated that factors which were associated with higher concentrations included ambient particle concentrations, numbers of bus stops, numbers of traffic stops, passenger activity, routes, types of buses, seat position and window status. The effect of these different factors varied between particle size classes. Re-suspension by passenger activity was identified as a major factor especially for coarse particles. This was also used as the only in-bus. emission source for the in-bus model (IBAIR) simulations. The simulation results indicated that the IBAIR model could broadly simulate the particle concentrations inside buses, and could be used to assess the contribution of activities within buses and outside concentrations to particle levels within buses. The results of both measurements and models suggest that exposure of regular commuters inside buses could be of potential health significance and needs further assessment given policies to encourage the use of public transport. Keywords: particulate matter, personal exposure, bus, transport, size distribution, modeling

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Abdullahi, Lami Karimatu. « Characterisation of particulate matter emissions from cooking ». Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7397/.

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Cooking fume have been found to be a significant component of ambient particulate matter and also to contribute to high concentrations of aerosol indoors. A linkage of individual exposure to cooking emissions with adverse health effects has been found and thus has led to the need for further understand the composition of this source of particulate matter. This study was concerned with gaining further insights into the chemical composition of aerosol generated from typical styles of cooking and the understanding of trends of the formation of particles among different culinary methods. Cooking source profile for African, Chinese, Western and Indian styles was obtained in a specially designed laboratory based kitchen. These profiles were used as input in a Chemical Mass Balance model where ambient data collected in Birmingham, UK were analysed in order to apportion the quantity of organic matter from cooking sources in the location sampled. It was found that cooking generated a significant mass of aerosol with the particle sizes largely within the respirable size range. The Chinese style of cooking was found to generate the highest concentration of particles with PM mass of 21.61µg/m3. The source profile from cooking obtained from the study were found to correlate well with each other with Indian and Western profiles exhibiting the highest correlation. When used for the CMB model runs, these two profiles provided the best output with the model runs apportioning 16% of the Organic Carbon to be from cooking, with traffic, wood smoke and soil debris contributing 44%, 18% and 24% respectively.

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Wheeler, Amanda Jane. « Children's personal exposure to airborne particulate matter ». Thesis, Middlesex University, 2001. http://eprints.mdx.ac.uk/13438/.

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Personal exposure to particulate matter (PM₁₀ and PM₂.₅) for ten children aged 9 - 11 years was measured between January and September 1997 in the London Borough of Barnet. Personal, home, garden and classroom micro environmental monitoring was successfully completed for all ten children. Each child was monitored for five consecutive days during winter, spring and summer, with the exception of one child who did not complete the summer session. All children completed daily time activity diaries to provide infonnationon any activities that could potentially influence their exposure patterns. Each evening parents completed a household activity questionnaire providing information on all particle generating activities such as cooking and cleaning. Personal Environmental Monitors were used for the personal sampling and Harvard Impactors for the microenvironmental sampling. The children's mean personal exposure concentrations for PM₁₀ during winter, spring and summer were 69, 69 and 32 ug/m³ respectively and for PM₂.₅ 21, 24 and 15 ug/m³ respectively. The strongest and most consistent associations were found between the personal and indoor exposure concentrations. The most significant correlations were observed between personal and home PM₁₀ with a median rs = 0.66. Classroom concentrations were the highest of all the sampled environments which could be attributed to the number of children present and the resuspension of particles. Ambient contributions of PM₂.₅ to PM₁₀ during the day were estimated to be 56%, which is comparable to other UK research. Indoor/outdoor concentrations were influenced by heating in the homes, however no significant specific particle generating activities in the home were found during the day. At night, home concentrations of PM₂.₅ appeared to be influenced by the presence of smokers. To determine potential sources of particulate matter, analysis of a sub sample of filters was undertaken using Scanning Electron Microscopy. Within the home particle composition was influenced by human activities predominantly; resuspended soil dust, skin flakes and fibres. The outdoor particles were predominantly biological in origin; pollen and insect debris. The composition of the personal exposure filters was a mixture of both environments and was dependant upon how much time each child spent in each of these environments. Smooth globular particles c.2um in diameter were found on all filters and could be combustion related, possible vehicle derived or from cooking activities. Measured data, along with the reviewed literature, provides some insight into the source apportionment of particulate matter. Analysis of questionnaire and time activity diaries also provides information on individual children's exposure patterns. Some estimation of potential health outcomes is discussed.

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Saunders, Vanessa C. « Mechanisms of Particulate Matter-Induced Experimental Asthma ». University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1267738359.

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Liu, Di. « Integral Measurement of Atmospheric Particulate Matter (PM) ». VCU Scholars Compass, 2018. https://scholarscompass.vcu.edu/etd/5573.

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Atmospheric aerosol particles also known as atmospheric particulate matter or particulate matter (PM) are microscopic particles (solid or liquid) suspended in air, which is one of six air pollutants in US air quality standard. PM is classified as coarse particles with diameters between 2.5 to 10 mm, fine particles with a diameter less than 2.5 mm (PM2.5), and ultrafine particles with the diameter less than 0.1 mm (PM0.1). Epidemiological studies have already showed the adverse health effects (such as asthma, lung cancer and respiratory and cardiovascular disease) resulted from exposure to the fine and ultrafine particles. Monitoring the PM concentration (i.e., either mass or surface area concentration of PM) is critical for the protection of public health and environment and for the regulatory control. Various PM sensors are now available in market. A majority of these PM sensors are optical sensors, whose readouts are highly depended on the physical property and composition of PM. Several PM monitors based on the measurement principle of electrical charging are also available. However, the empirical calibration of the readout of these electrical PM monitors via the use of standard dust particles makes it difficult to obtain the true mass concentration of PM when PM size distribution is different from that of standard dust. The overall objective of this dissertation is to advance our scientific knowledge on the performance of cost-effective PM monitors for measuring either mass or surface area concentration of fine and ultrafine PM. This thesis includes two parts: (1) is on the evaluation of existing PM sensor for PM mass concentration measurement; (2) is on the development of new PM monitor for PM surface area concentration measurement. For the first part of this dissertation, four low-cost optical sensors, one Personal Dust Monitor (PDM) and DustrakTM were experimentally evaluated. Particles in the size distribution having different mean size, standard deviation value and material were used as test aerosol particles. The readouts of these low-cost and portable sensors are compared to that of a standard TEOM (Tapered Element Oscillation Microbalance). For the second part of this dissertation, a new electrical PM monitor, consisting of a corona-based aerosol charger, a precipitator and high sensitive current meter, has been proposed for measuring surface area concentration of fine and ultrafine PM. Particles are electrically charged upon entering an electrical PM monitor. Instead of using Faraday cage and current meter to measure the charges carried by particles in existed electrical PM sensors, the new PM monitor measures the current carried by particles deposited directly on the wall of the precipitator. A thorough evaluation has been carried out to evaluate the fundamental performance of this new PM monitor. In addition, small cyclones (i.e., quadru-inlet and tapered-body cyclones) were also evaluated as the size-selective inlet of these PM sensors/monitors to minimize the potential interface from the presence of PM with large sizes in the air. The small quadru-inlet cyclone is to resolve the issue of directional sampling; and the tapered-body cyclones is to reduce the cyclone pressure drop while having small cyclone cutoff particle size. Each cyclone has been evaluated via the measurement of particle penetration curve and pressure drop. Semi-empirical models have been obtained for the prediction of cyclone performance.

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Kayes, David J. (David Jonathan) 1972. « Particulate matter formation in spark-ignition engines ». Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/9417.

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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1999.
Includes bibliographical references (leaves 180-184).
Recent health concerns over airborne particulate matter (PM) have prompted examination of the mechanisms by which PM is formed in spark ignition (SI) internal combustion engines. A study was undertaken in order to understand the effects of dilution on measured PM, to examine and model the effect of steady state engine operating conditions on engine-out PM, and to characterize the effect of transient engine conditions on particle growth and dynamics. Particle dynamics in diluted SI and compression ignition (Cl) engine exhaust are examined and discussed in the context of SI exhaust dilution. Temperature measurements in the exhaust pipe and dilution tunnel reveal the degree of mixing between exhaust and dilution air, the effect of flowrate on heat transfer from undiluted and diluted exhaust to the environment, and the minimum permissible dilution ratio for a maximum sample temperature of 52°C. Measurements of PM concentrations as a function of dilution ratio, using a Scanning Mobility Particle Sizer (SMPS), show the competing effects of temperature and particle/vapor concentrations on particle growth dynamics, which result in a range of dilution ratios - from 13 to 18 - where the effect of dilution ratio, independent of flowrate, is kept to a minimum and is therefore optimal in order to achieve repeatable PM concentration measurements. Particle dynamics in transit through the dilution tunnel are measured and compared to previous research. PM emissions are strongly affected by steady state engine parameters that affect global and local air/fuel ratios, the concentration of liquid fuel in the cylinder, and the availability of soot precursors. PM emissions vary by up to six orders of magnitude between the fuels tested, when at the same fuel/air equivalence ratio. Minimum PM concentrations are emitted at a global fuel/air ratio within 10% of stoichiometric, with the exact value depending on the particular fuel, and concentrations can increase by more than three orders of magnitude when the fuel/air ratio is either increased or decreased 30% from stoichiometric. Burning liquid fuel is a significant source of PM, as evidenced by the fact that open valve fuel injection increases PM emissions by up to three orders of magnitude relative to closed valve injection. Coolant and oil temperatures, spark timing, and Exhaust Gas Recirculation (EGR) affect PM through their effect on intake port and cylinder temperatures, as well as through the effect on the availability of liquid fuel in the cylinder. Particles derived from oil consumption were found to be between zero and 40% of the total PM concentration for the oils used in the present experiments. Differences in PM emissions with and without the catalytic converter are not statistically significant. Particulate number and mass concentrations plus particle sizes are addressed in the present paper, as is the correlation between PM and emissions of gaseous pollutants - hydrocarbons (HCs), oxides of nitrogen (NOx), oxides of carbon (CO and CO2) - as well as oxygen and characteristic temperatures and pressures during the engine cycle. A model of PM formation via homogeneous- and heterogeneous-phase reactions, growth via condensation and adsorption/absorption of vapors, and diminution via oxidation explains the observed behavior of PM emissions with respect to each of the engine, fuel, and dilution parameters above. PM emissions during transient engine operation are generally a first-order time response with characteristic times similar to those involved in the fuel evaporation process, suggesting that PM emissions respond to instantaneous engine conditions and may be modeled using a quasi-steady state application of the model.
by David Kayes.
Ph.D.

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Perez-Castillo, Fernando. « Sedimentation of organic matter on the Hebridean slope ». Thesis, Bangor University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287026.

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Fuchs, Luiz Fernando Portugal. « Efeitos da poluição do ar na adrenal de camundongas : aspectos histomorfométricos e imunoistoquímicos ». Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/5/5139/tde-25112014-112036/.

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INTRODUÇÃO: A poluição em centros urbanos é produzida, principalmente, pela queima de combustíveis fósseis. Constitui problema que afeta a saúde da população, provocando doenças tanto no sistema respiratório, como sistemicamente em vários órgãos. Dentre as funções afetadas, realça o impacto da poluição sobre o sistema endócrino, podendo acometer as adrenais, tanto, no ser humano, como em roedores. Todavia, pouco se conhece sobre a ação nesta glândula. Assim, propusemo-nos a analisar os efeitos do ar poluído sobre as adrenais em duas gerações consecutivas de camundongas. OBJETIVOS: Analisar os efeitos do ar concentrado com material particulado (MP) 2,5um sobre as adrenais, avaliando as alterações histomorfométricas; a angiogênese pelo fator de crescimento vascular endotelial (VEGF-A); a pela proliferação celular por meio da proteína Ki-67 e o índice de apoptose pela caspase 3-clivada nas três zonas do córtex da adrenal. MATERIAL E MÉTODOS: Utilizaram-se 20 camundongas alocadas em biotério livre de poluentes, as quais foram acasalados na proporção de um macho para duas fêmeas. Após confirmação da cópula, foram divididas em 2 grupos de 10 animais cada. Acondicionou-se um grupo diariamente em uma câmara, onde as camundongas foram expostas a MP 2,5um à concentração de 600ug/m³ (G0P). O outro grupo, com 10 animais, foi alocado em outra câmara com ar filtrado (G0NP). A exposição ocorreu diariamente durante toda a prenhez das camundongas. Ao nascimento os conceptos, foram amamentados por 30 dias em amamentação, período onde não houve exposição aos poluentes. Após este período, as mães foram eutanasiadas para coleta das adrenais e as filhas sofreram o mesmo protocolo de exposição (G1P e G1NP - submetidas e não submetidas à poluição), não foram acasaladas, sendo eutanasiadas para coleta das adrenais ao fim do protocolo. As adrenais passaram por processamento histológico para coloração de H.E. e imunoistoquímico. RESULTADOS: As adrenais do grupo G0P apresentaram maior espessura da zona glomerulosa e as do G1P apresentaram maior quantidade de espongiócitos na zona fasciculada. As adrenais do grupo G1P tiveram maior imunoexpressão de VEGF-A na zona glomerulosa do que as do G1NP. A imunoexpressão do Ki-67 foi maior na zona reticulada no grupo G0P; no grupo G1P houve maior expressão do Ki-67 na zona glomerulosa do que no grupo G1NP. A imunoexpressão da caspase-3 clivada foi maior nos grupos G0P e G1P do que nos demais. CONCLUSÃO: A exposição ao ar poluído com material particulado 2.5?m determinou alterações histomorfométricas e imunoistoquímicas nas três zonas do córtex da adrenal de duas gerações consecutivas de camundongas. Estas alterações poderiam causar distúrbios endócrinos e cardiovasculares
INTRODUCTION: The pollution in urban centers is produced mainly by the burning of fossil fuels. It\'s a concern of public health, causing diseases in both the respiratory system and the other organs. Among the affected functions, it is important to highlight the impact of pollution on the endocrine system and this effect on the adrenal glands, both in humans and in rodents. However, little is known on the action of pollutants on this gland. Therefore, the aim of this study was to analyze the effects of polluted air on the adrenal in two consecutive generations of female mice. OBJECTIVES: To assess the effects of concentrate air with particulate matter (PM) 2.5um on the adrenal cortex evaluating histomorphometric changes; angiogenesis by vascular endothelial growth factor (VEGF-A); the cell proliferation by Ki-67 index and apoptosis by cleaved caspase-3 in the three zones of the adrenal cortex. MATERIAL AND METHODS: We used 20 female mice in their cages free of pollutants. Those animals were mated at a ratio of one male to two females. After mating confirmation, animals were divided into 2 groups of 10 animals each. A group was daily allocated in a chamber where the female mice were exposed to PM 2.5um at a concentration of 600ug/m³ (G0P). The other group of 10 animals was allocated in another chamber with filtered air (G0NP). The exposure occurred daily throughout pregnancy period. At birth, the fetuses were breastfed for 30 days. During breastfeeding period there was no pollutants exposure. After this period, mothers were euthanized for adrenal collection and daughters suffered the same exposure protocol (G1P and G1NP - exposed and not exposed to pollution), but those were not mated, being euthanized for adrenal collection at the end of the protocol. The adrenal underwent histological processing for H.E. staining and immunohistochemistry. RESULTS: The adrenal of the G0P group had increased thickness of the zona glomerulosa and the G1P presented more espongiocytes in the zona fasciculata. The adrenal of the G1P group had higher immunoreactivity of VEGF-A in the zona glomerulosa than one of the G1NP. The immunoreactivity of Ki-67 in the zona reticularis of G0P group was higher one of G0NP; there was a higher expression of Ki-67 in the zona glomerulosa of the G1P group compared to G1NP group. The immunoreactivity of cleaved caspase-3 in G0P and G1P was higher than ones of other groups. CONCLUSION: Exposure to air pollution with particulate matter 2.5um determined histomorphometric and immunohistochemical changes in the three adrenal cortical zones of the two consecutive generations of mice. These changes could cause endocrine and cardiovascular disorders

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Sineri, Jaclyn R. « Assessment of Particulate Matter Exposure in Franklin County, Ohio : A Comparison of Static and Dynamic Approaches ». The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1269018692.

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Pan, Xiaoxi. « Fibrin clot structure alterations after particulate matter exposure ». Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/14310/.

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Particulate matter (PM) as an important part of ambient air pollution has been associated with increased risks of cardiovascular diseases. Fibrin clot structure alteration is an emerging risk factor of many cardiovascular diseases, especially thrombosis. Therefore, the aim of this study was to investigate whether and how air particulate matter affects fibrin clot structure and endothelial cell behaviour. Turbidity assay, turbidity lysis assay and laser scanning confocal microscopy were used to analyse clots formed from normal pooled plasma or purified fibrinogen, in the presence of varying concentrations of PM. It was found that clots formed from plasma with higher concentrations of particles led to prolonged lysis time compared to control. No differences were seen for clots formed from fibrinogen. In a study of clots formed from plasma samples collected as part of a previous study on the effects of air pollution on deep vein thrombosis (DVT), alterations were observed in clots formed from plasma of DVT patients exposed to high levels of PM compared to those exposed to low levels, but the same differences were not observed in clots formed from plasma of control subjects. To investigate the potential role of venous endothelial cells in moderating clot structure following exposure to PM, human umbilical vein endothelial cells (HUVEC) were treated with PM for 24 hours and clots subsequently formed on the cells. Clots formed from plasma on the treated cells were altered compared to controls. RT-PCR and ELISA results showed increased gene expression of tissue factor (TF), protein expression of von Willebrand Factor (VWF) and plasminogen activation inhibitor-1 (PAI-1) and decreased thrombomodulin mRNA expression which were consistent with changes observed in clot structure. Engineered SiO2 nanoparticles caused denser clot structure in clots formed from normal pooled plasma. The gene expression of thrombomodulin was inhibited by SiO2 nanoparticles, but there were no significant difference in the TF mRNA expression between control and treated cells. Silica NPs caused increased concentrations of VWF, but not PAI-1 produced by endothelial cells. The results presented here show that PM can induce changes to clot structure and function, and that changes in gene expression induced in endothelial cells may be a mechanism by which a prothrombotic state is induced in response to PM exposure. Furthermore, some, but not all, similar changes were observed in clots and cells exposed to SiO2 nanoparticles, raising the possibility that such engineered nanoparticles may also have the potential to contribute to cardiovascular toxicity.

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Chan, Wing-man Polly. « Aspects of air quality management for particulate matter / ». View the Table of Contents & ; Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37120803.

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Chung, Winson. « Characterisation of particulate matter in the urban environment ». Thesis, University of Sheffield, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.505424.

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At present, airborne particulate matter (PM) is considered to be one of the most important environmental pollutants. Conventional epidemiological studies and PM monitoring methods are dated and are not a proper representation of the actual effects of airborne PM on the environment and human health. There are numerous studies over the years identifying particles emitted from their source, however, less is known about particles which exists in the urban environment other than size distribution data and bulk chemical analysis. Thus the main objective of this research project was to develop a comprehensive receptor level characterisation of particulate matter in the urban environment. The overall objective was achieved by using a three-stage approach. In the first stage, tapered element oscillating microbalance (TEOM) samples were collected from sites around the city of Sheffield over a period of one year. The Andersen instrument was then used to collect samples from kerb-side and elevated locations, Ladybower (a forest environment) and from a UK energy-from-waste plant. Then in the second stage, samples were subjected to individual particle morphology andú chemical composition analysis. Finally, the samples were analysed for bulk chemical composition for the purpose of source apportionment and identification of emission trends over the one-year period. Tests showed that the monitoring stations in residential environments were dominated by transportation derived particles and other migratory particulates such as sea salt, cenospheres, dust, etc. The results from the city centre monitoring stations showed that transportation and biological particles were dominant, with biological particles abundant for the site closest to the River Don. The monitoring station located close to the Tinsley industrial area, despite only 200 meters away from the Ml motorway, has low contribution of nonexhaust particulates from vehicles. Instead, the particulates collected from this site were dominated by industrial sources. Additionally, an air dispersion model was carried out using the Airviro program. The model was set-up to simulate the dispersion of particulate matter from all points and road sources in the city over the one-year sampling period. Results from the modelling corresponded with the results obtained in the experimental program. It further suggests that the high background PMlO levels could be attributed to the construction and demolition work around the city. This PhD has yielded valuable information that can be used for future health and environmental studies in order to improve the way in which PM exposure is assessed. Furthermore, the methodology of this study can be used to identify and characterise even finer particles such as nano-particulates. The information on the morphology and chemical characteristics of individual particulates can also be used to design or improve the current abatement systems.

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Chan, Wing-man Polly, et 陳詠文. « Aspects of air quality management for particulate matter ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B45013354.

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Micallef, Alfred. « Concentrations and vertical profiles of airborne particulate matter ». Thesis, University of Nottingham, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285453.

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Lingard, Justin Jonathan Nicholas. « Size distributional analysis of urban airborne particulate matter ». Thesis, University of Leeds, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.414252.

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Brujić, Jasna. « Experimental study of stress transmission through particulate matter ». Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.615997.

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Hibbs, Leon R. « Metal content of airborne particulate matter in Edinburgh ». Thesis, University of Edinburgh, 2002. http://hdl.handle.net/1842/12077.

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Daily 24 hour (00:00 - 24:00) co-located PM₁₀, PM_2.5, and Black Smoke samples were collected for a period of 1 year (September 1999 to September 2000) at an urban background site in central Edinburgh, and monthly at a rural site 30 km SSW of Edinburgh. Sample mass concentrations were determined gravimetrically, and the daily water and acid (2.8:1 HCl/HNO₃ v/v) extractable metal concentrations of Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Cd, and Pb, determined by ICP-MS. Median urban background PM_2.5 water soluble metal concentrations ranged from 0.05 ng m^-3 for Ti to 5.06 ng m^-3 for Pb, and in PM₁₀ from 0.18 ng m^-3 for Ti to 11.74 ng m^-3 for Fe. Median PM_2.5 total (water + acid) extractable metal concentrations ranged from 0.30 ng m^-3 for As to 27.60 ng m^-3 for Fe, and in PM₁₀ from 0.37 ng m^-3 for As to 183.44 ng m^-3 for Fe. Fe concentrations represented c. 80% of the total (water + acid) metal exposure from metals analysed in the PM₁₀ fraction, although Pb and Zn constituted over 50% of the water soluble metal exposure in PM_2.5. Significant seasonal differnces (P <0.05) were observed in the metal concentrations, which varied with metal, coupled with an overall shift towards a higher proportion of acid extractable/lower proportion of water soluble metal in the winter months. Seasonal differences were also present in the urban : rural ratio, which ranged from ~3 in the spring to up to ~10 in winter. Urban background metal concentrations were also found in general to correlate more strongly with BS ‘mass concentration equivalent’ than with PM₁₀ or PM_2.5 mass concentrations. Hierarchical clustering of 5 day air mass back trajectories demonstrated that there were significant differences (P <0.05) in metal concentrations (ng m^-3) and metal ‘enrichment factors’ (EFs, ng μg^-1 particulate matter) depending on air mass source/direction.

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Nguyen, Thu Ha. « Flocculation dynamics of cell-associated suspended particulate matter ». Thesis, University of Sydney, 2020. https://hdl.handle.net/2123/23148.

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Transport of suspended particulate matter (SPM) plays a vital role in controlling large-scale processes related to geophysical flows such as dispersal and sinking of organic matter and contaminants to offshore and deep waters, nutrient cycles, food web stability, morphodynamics and sedimentation in both limnetic and pelagic ecosystems. Although it has been recognized that small-scale microbial processes can introduce substantial differences to the way in which SPM moves in natural waters, the extent to which the attached biological matter affects SPM dynamics is still not well characterized. This thesis focuses on quantifying the attached biomass fraction on SPM aggregates and investigating its contribution to SPM flocculation dynamics, which consequently control SPM aggregate geometrical properties and transport. A novel laboratory-based Optical Measurement of Cell Colonization (OMCEC) system and a microbiological-physical model (BFLOC2) are the main achievements of this thesis that allow the analyses of the correlations between environmental conditions, aggregate-attached biomass fraction, cell colonization patterns, aggregate size, fractal dimension and settling velocity. OMCEC is an experimental system that can simultaneously measure the material composition, geometric properties, and motion of individual suspended aggregates in a non-invasive and non-destructive way. OMCEC consists of a full-color high-resolution optical system and real-time algorithms for (i) material segmentation based on light spectra emission analysis, (ii) quantification of various geometrical properties, and (iii) motion detection with micro particle tracking velocimetry (μPTV). OMCEC was applied herein on three types of aggregates: cell-associated minerals, cell-associated microplastics, and three-phase aggregates made of minerals, microplastics, and biological matter. OMCEC application on Saccharomyces cerevisiae-colonized minerals at four sucrose concentrations showed the likelihood of cell colonization to increase with increasing nutrient concentration. The attached biomass fraction was found to increase nonlinearly regarding an increase of aggregate size but almost constant with fractal dimension variation. Cell distribution on mineral surfaces was then analyzed and classified into three colonization patterns: (i) scattered, (ii) well-touched, and (iii) poorly-touched, with the second being predominant. Cell clusters in the well-touched pattern were found to have lower fractal dimension than those in the other patterns. A strong correlation of colonization patterns with aggregate biomass fraction and properties suggests dynamic colonization mechanisms from cell attachment to minerals, to joining of isolated cell clusters, and finally cell growth over the entire aggregate. OMCEC application on microplastics (MPs) being colonized by natural biological matter from Hawkesbury River, NSW, Australia demonstrated that the biomass fraction of MP aggregates has substantial control over their size, shape and, most importantly, their settling velocity. Polyurethane MP aggregates made of 80% biological matter had an average size almost double that of MP aggregates containing 5% biological matter and sank two times slower. Based on our experimental data, we introduce a settling velocity equation that accounts for the shape irregularity and fractal structure of MP aggregates. This equation can capture the settling velocity of both virgin MPs and cell-associated MP aggregates with 7% error and can be applied widely to predict the settling flux of MP aggregates made of different polymers and various types of biological matter. To consider the complex genesis of cell-associated mineral aggregates, the BFLOC2 model was introduced to predict aggregate geometry and settling velocity under simultaneous effects of hydrodynamic and biological processes. While minerals can contribute to aggregate dynamics through collision, aggregation, and breakup, living microorganisms can colonize and establish food web interactions that involve growth and grazing, and modify the aggregate structure. Modeling of cell-associated mineral aggregate dynamics over a wide range of environmental conditions showed that maximum aggregate size, biomass fraction, and settling velocity could occur at different optimal environmental conditions. Unlike mineral aggregates, which have maximum size when shear rates tend to zero, a relative maximum size of cell-associated mineral aggregates can be reached at intermediate shear rates as a result of microbiological processes. The settling velocity was ultimately controlled by aggregate size, fractal dimension, and biomass fraction. The innovative aspect of this thesis is the simultaneous quantification of composition, architecture, and settling velocity of individual aggregates. Therefore, it puts forth the analysis and prediction of cell colonization impacts on dynamics and transport of suspended particulate matter in natural waters. The output of this thesis can be used in natural water monitoring programs to estimate the biological content based on SPM size, capacity dimension, and settling velocity, which can be measured using in-situ methods. Furthermore, the evidence and tools to quantify the sinking and floating of microplastic subjected to bio-fouling can be implemented in microplastics transport models to enable the three-dimension modeling of both low- and high-density microplastics. The BFLOC2 model can be coupled to traditional sediment transport models to better describe the sediment formation dynamics, thus giving a more precise prediction of sedimentation and carbon flux to deep waters and offshore.

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Beauboeuf, Daniel P. « Microscopy investigations of ash and particulate matter accumulation in diesel particulate filter surface pores ». Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/59894.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2010.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 60).
There has been increased focus on the environmental impact of automobile emissions in recent years. These environmental concerns have resulted in the creation of more stringent particulate matter emissions regulations in the United States and European Union. These limits have forced diesel engine manufacturers to reduce particulate matter (PM) emissions by an order of magnitude beginning in 2007. Diesel particulate filters (DPF) provide the most effective means of reducing PM emissions from diesel exhaust. DPFs can reduce over 99% of PM in the exhaust. DPF effectiveness is limited by the accumulation of ash. Ash is comprised of incombustible material from engine lubricants. Engine oil additives based on P, Zn, S, Ca, and Mg are responsible for the majority of ash. Ash accumulation in DPFs reduces their useful life by plugging the filter's inlet channels. Ash deposition leads to increased pressure drop across the DPF, which reduces the engine's performance and negatively impacts fuel economy. The process of ash accumulation in DPF channels is not well understood. This research is focused on exploring the ash interactions with DPF walls, pores, and the catalyst washcoat. Based on scanning electron microscopy analysis of ash loaded DPFs from the field and from filters loaded with ash in the laboratory, a mechanism for ash accumulation is presented.
by Daniel P. Beauboeuf.
S.B.

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Moraes, Alexandre Perri de. « Qualidade do ar interno com ênfase na concentração de aerodispersóides nos edifícios ». Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/3/3146/tde-17112006-134242/.

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No presente trabalho, é avaliada a qualidade do ar interno com ênfase na concentração de aerodispersóides presentes em edifícios comerciais e residenciais com sistema de ventilação natural ou condicionamento de ar. De fato, algumas doenças de origem ocupacional são causadas pela inalação de aerodispersóides nocivos à saúde. O método utilizado para avaliar a qualidade do ar interno nos edifícios comerciais e residenciais consistiu primeiramente em caracterizar os medidores de aerodispersóides e em seguida passou-se para a análise das concentrações e das características ambientais. A pesquisa mediu a concentração de aerodispersóides em edifícios com sistemas de ventilação diferentes (1a fase), e identificou as principais fontes de emissão de aerodispersóides em um apartamento residencial (2a fase). Observou-se que as concentrações obtidas na pesquisa estão acima dos valores recomendados na RE n° 9 (ANVISA, 2003) e por Morawska et al. (1999) que atribuem valores de 80 µg/m³ e 7.400 part./cm³, para concentrações médias em massa e em número, respectivamente. Com base nas observações acima, chegou à conclusão que as concentrações médias em massa e em número de aerodispersóides, durante as atividades domésticas (cozimento, reforma, limpeza, entre outras), foram várias vezes maiores do que as concentrações obtidas em ambientes com atividades profissionais ou com menor ocupação durante o dia.
This paper is the result of quality evaluation of indoor air quality with emphasis on the concentration of aerodispersoid in commercial and residential buildings with natural ventilation or air conditioning systems. In fact, some of the occupational diseases are caused by the inhalation of aerodispersoids hazardous to health. The method applied to evaluate the indoor air quality in commercial and residential buildings consisted firstly of characterizing the aerodispersoid measuring devices and subsequently analyzing the concentration levels and environmental characteristics. This research measured the concentration of aerodispersoids in buildings equipped with a variety of ventilation systems (phase1) and next it identified the main emission sources in a residential apartment (phase 2). It was observed that the concentration levels measured were above the specifications recommended by RE n° 9 (ANVISA, 2003) and by Morawska et al. (1999) which attribute values of 80 µg/m³ and 7.400 part./cm³, for average concentration in mass and number respectively. Based on the above information it was concluded that the average concentration levels of aerodispersoids in mass and number in home related activities (cooking, restoration, cleaning, etc) were many times higher than the concentration levels found in business environments or in environments with less occupation during the day.

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Martins, Bruno Henrique. « Aspectos químicos e potencial de sequestro de carbono em áreas sob diferentes manejos de solo ». Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/75/75135/tde-24022014-111711/.

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O objetivo do presente estudo foi avaliar a dinâmica e reatividade da matéria orgânica do solo (MOS) e substâncias húmicas (SH) em duas situações distintas, no que concerne ao manejo de solo, práticas agroflorestais e condições climáticas, avaliando o potencial de sequestro de C e mitigação de efeitos do aumento do efeito estufa. O estudo foi conduzido em dois campos experimentais, sendo o primeiro, instalado em Beltsville - Maryland, Estados Unidos, sob coordenação do Departamento de Agricultura norte-americano (USDA/ARS), composto por sistemas agrícolas convencionais com manejo mínimo (PC), plantio direto sem manejo (PD) e orgânicos com plantio direto (2, 3 e 6 anos, com adição de esterco aviário). O segundo campo experimental, instalado em Itatinga - São Paulo, Brasil, compreende área de reflorestamento de floresta de eucalipto, em duas fazendas (Entre Rios - ER - e Areona - AN) com perfis de solo diferentes (Latossolo e Neossolo quartzarênico, respectivamente) com e sem adição de biossólido. Para o primeiro campo foram coletadas amostras de solo até 30 cm em 5 incrementos, sendo realizado, em seguida, o fracionamento físico da MOS, em matéria orgânica particulada livre (MOPl) e oclusa (MOPo) para análises de espectroscopia na região do infravermelho (MIR) e pirólise acoplada a GC/MS (PY-GC/MS). Para o segundo campo experimental foram coletadas amostras de solo até 20 cm, seguindo de extração de SH para análises espectroscópicas. No campo experimental americano, observou-se maior teor de C nos sistemas de plantio direto, sobretudo nos sistemas orgânicos, em comparação ao sistema convencional (cerca de 24% de aumento). Os dados obtidos através da espectroscopia de MIR mostraram maiores graus de condensação e hidrofobicidade, influindo em maior humificação e resistência à atividade microbiana para as amostras nos sistemas orgânicos. Os resultados de PY-GC/MS foram analisados por testes não paramétricos de Kruskal-Wallis e Mann-Whitney, sendo observada a maior incidência de estruturas moleculares de caráter fenólico aromático em amostras de MOPo para os sistemas orgânicos considerados, e a maior ocorrência de núcleos condensados, oriundos de lignina e outras fontes, ligados a cadeias alifáticas em amostras de MOPl para os mesmos sistemas, em relação aos demais analisados em estudo. Os resultados obtidos para o campo experimental americano ilustrou maior impacto do manejo orgânico do solo, frente aos demais considerados, no que concerne ao potencial acumulo de carbono e incidência de estruturas mais condensadas e de maior recalcitrância. Os dados do segundo campo experimental, em áreas de reflorestamento de eucalipto no estado de São Paulo, demonstraram comportamentos distintos com maior teor de C e menor grau de humificação (cerca de 25 e 30%, respectivamente) para áreas submetidas à adição de biossólido para a fazenda Areona (AN), sendo observado perfil inverso para a fazenda Entre Rios (ER) (decréscimo de cerca de 20% para C e aumento de, aproximadamente, 100% no grau de humificação). Através dos dados obtidos através de espectroscopia de infravermelho, pôde-se observar maiores índices de condensação (grau de humificação), em ambas as fazendas, nas áreas sob adição de biossólido, ao passo que somente na fazenda ER foram observados maiores índices de hidrofobicidade (resistência à degradação microbiana) nestas mesmas áreas. Assim como nos resultados obtidos as amostras de solo intacto, foi observado maior grau de humificação para amostras de AH na fazenda ER, em áreas condicionadas com biossólido, ao passo que menor grau de humificação para as mesmas áreas na fazenda AN. Assim sendo, conforme mencionado, uma das áreas de reflorestamento tratada com biossólido mostrou aumento no teor de carbono no solo (em solo arenoso) e a outra mostrou decréscimo (solo com teor mediano de argila). As análises qualitativas, como determinação do grau de humificação da matéria orgânica em amostras de solos e substâncias húmicas, foram coerentes com o aumento ou decréscimo dos teores de carbono nos dois solos, dando consistência as observações das duas situações de campo analisadas. Dessa maneira, verificou-se o maior impacto da adição da aplicação de biossólido em Latossolos em relação à área de Neossolo quartzarênico. O entendimento e avaliação da resposta da matéria orgânica e seus constituintes húmicos frente a diferentes situações é de extrema importância para obtenção de sustentabilidade ambiental, no que concerne à mitigação de efeitos inerentes às mudanças climáticas globais.
The aim of the following study was to evaluate the dynamics and reactivity of soil organic matter (SOM) and humic substances (HS) in two different situations, regarding soil tillage, forestry practices and climate conditions, considering C sequestration potential and greenhouse effects mitigation. The study was conducted in two different field experiments, being the first one a long-term field trial project installed in Beltsville, Maryland - United States, coordinated by the United States Department of Agriculture (USDA), comprising different soil tillage systems as it follows: chiesel till (CT), no till (NT) and 2, 3 and 6-year organic agriculture (with poultry manure addition). The second experimental field was installed in Itatinga, São Paulo - Brazil, comprising an eucalyptus forestry system being two farms (Entre Rios - ER, and Areona - AN), presenting different soil prolife (Oxisol and Quartzarenic Neosoil) and sewage sludge (SS) amended areas. For the first experimental field soil samples were collected to 30 cm depth in 5 increments, followed by SOM physical fractionation in occluded and free particulate organic matter (oPOM and fPOM, respectively) for mid infrared (MIR) spectroscopy and pyrolysis coupled with gas chromatography/mass spectrometry (PY-GC/MS) analysis. For the second experimental field, soil samples were collected to 20 cm depth, followed by HS extraction and spectroscopic analysis. The results for the first experimental field showed a C content increase (about 24%) for the organic systems, comparing to the others considered. Data obtained by MIR spectroscopy showed higher condensation and hydrophobicity degrees, resulting in higher humification and microbial decomposition resistance, for the organic systems samples. The results obtained by PY-GC/MS were analyzed by Kruskal-Wallis and Mann-Whitney non parametric tests and it was observed a higher incidence of phenolic and aromatic molecular structures in oPOM samples, and a higher occurrence of condensed structures, derived from lignin and other sources, bonded to aliphatic chains, in fPOM samples for the organic systems analyzed, comparing to the others systems considered. This way, the results obtained for the American experimental field showed a higher impact of organic tillage systems, regarding the soil carbon accumulation potential and the incidence of more condensed and recalcitrant structures. The results regarding the second experimental field showed an interesting behavior with C content increase and humification degree decrease in the SS amended areas (about 25 and 30%, respectively) for the Areona (AN) farm, nevertheless, being observed an inverse behavior for the Entre Rios (ER) farm samples (about 20% C content decrease and nearly 100% humification degree increase). From the infrared spectroscopy data it could be observed higher condensation degree (inferring higher humification degree) in the SS amended areas for both farms considered, however only for the ER samples it was noted a higher hydrophobicity degree (higher microbial decomposition resistance). The same way noted for the soil samples, it was observed higher humification degree for humic acids samples in the SS amended areas for the ER farm, while for the AN samples it was noted smaller humification degree for its respective SS amended area. This way, as mentioned before, one of the SS amended forestry areas showed an increase in the soil C content (in the quartzarenic neosoil) while the other one presented soil C content decrease (oxisoil, with about 20% clay content). The qualitative analysis, such as organic matter humification degree determination for soil and HS samples were coherent to the C content increase or decrease observed for both soil profiles, being consistent to the results obtained on the field experiment scenario. This way, the results for the Brazilian experimental field showed a higher impact of the sewage sludge application in the Oxisol area, comparing to the Quartzarenic Neosoil one. The understanding and evaluation about organic matter and humic constituents response regarding different field situations is extremely important to achieve environmental sustainability and climate change effects mitigation.

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