281 |
Development of graph-based artificial intelligence techniques for knowledge discovery from gene networks / 遺伝子ネットワークからの知識発見に資するグラフベースAI技術の開発Tanaka, Yoshihisa 23 March 2022 (has links)
京都大学 / 新制・課程博士 / 博士(薬学) / 甲第23844号 / 薬博第851号 / 新制||薬||242(附属図書館) / 京都大学大学院薬学研究科薬学専攻 / (主査)教授 山下 富義, 教授 石濱 泰, 教授 金子 周司 / 学位規則第4条第1項該当 / Doctor of Pharmaceutical Sciences / Kyoto University / DFAM
|
282 |
Determinação de clorobenzenos em água por cromatografia de fase gasosa com headspace / Determination of chlorobenzenes in water by gas chromatography headspaceMargarida Maria Sartori Tavares 29 February 2012 (has links)
As preocupações com o meio ambiente em particular com a água, adquirem especial importância, porque as demandas estão se tornando cada vez maiores, sob o aspecto crescente da população e das atividades industriais. Quando se fala em água subterrânea, a primeira ideia que surge é que ela seja potável. Mas nem sempre isso é uma verdade. Em área urbana, os crescentes números de problemas devido a contaminação, na maioria das vezes por vazamentos de combustíveis oriundos dos tanques de armazenamento dos postos de gasolina. Sem falar nas indústrias que também oferecem potencial risco de contaminação para esses corpos hídricos e são pouco divulgadas. O presente trabalho tem como foco determinar os compostos clorobenzenos por cromatografia de fase gasosa com headspace (CG-HS) em matriz água e validar a metodologia. A metodologia usada neste estudo foi cromatografia de fase gasosa com headspace (CG HS), por ser uma técnica excelente e sensível e é utilizada para determinar compostos voláteis em baixas concentrações. Os dados obtidos foram tratados estatisticamente de modo avaliar a seletividade, os limites de detecção e quantificação, a faixa linear de trabalho, a linearidade e a recuperação. As recuperações variam de 80 a 110%, os coeficientes de variação obtidos foram menor que 20%, todas as substâncias estudadas apresentaram linearidade na faixa de trabalho de 0,8 a 100g.L-1.
Foram estudadas 10 amostras de água subterrânea do Município do Rio de Janeiro e nas amostras analisadas foram encontrados todos os compostos em estudo, com faixa de concentração: monoclorobenzeno (<0,8 a 2,988g.L-1); 1,3-diclorobenzeno (<0,8 a 23,067g.L-1); 1,4-diclorobenzeno (nd a 16,160g.L-1); 1,2-diclorobenzeno (<0,8 a 48,685g.L-1); 1,3,5-triclorobenzeno (<0,8 a 21,900g.L-1); 1,2,4-triclorobenzeno (1,007 a 183,808g.L-1) e 1,2,3-triclorobenzeno (<0,8 a 126,886g.L-1) / The concerns with the environment, in particular with water, acquire special importance, because the demands become ever higher, under the growth of the population and industrial activities aspects. When speaking about underground water, the first notion that comes to mind is that it is potable water. But thats not always a true. In urban areas, the increasing numbers of problems due to contamination, is caused, most of time, by leaking gas tanks of gas stations. Not to mention industries that also offer the potential risk of contamination of these water bodies and that less divulged. The present work is focused in determining chlorobenzenes by headspace gas chromatography (HS-GC) in the water and validating its methodology. The methodology used in this work was headspace gas chromatography (HS-CG), because of its excellence technique and sensitive, applied for determining low concentrations volatile compounds. The data was statistically treated so to evaluate the selectivity, quantitation and detection limits, work range linearity, linearity and recovery. The recoveries vary between 80 to 110%, the variation obtained were less than 20%, all compounds present linearity in the work range 0,8 of 100g.L-1. .
Ten samples of underground water of Rio de Janeiro were tested, and all the samples contained the studied compounds, as and range concentration: chlorobenzene (<0,8 a 2,988g.L-1), 1,3-dichlorobenzene (<0,8 a 23,067g.L-1), 1,4-dichlorobenzene (nd a 16,160g.L-1), 1,2-dichlorobenzene (<0,8 a 48,685g.L-1), 1,3,5-trichlorobenzene (<0,8 a 21,900g.L-1), 1,2,4-trichlorobenzene (1,007 a 183,808g.L-1) and 1,2,3-trichlorobenzene (<0,8 a 126,886g.L-1)
|
283 |
Oxidation of toluene traces in gas phase in presence of manganese-oxide based catalysts : relationship structure-activity / Oxydation de traces de toluène en phase gazeuse en présence de catalyseurs à base de manganèse : relation structure réactivité. / Ossidazione di tracce di toluene in fase gassosa in presenza di catalizzatori a base di ossido di manganese : relazione struttura-attivitàSihaib, Zakaria 26 February 2018 (has links)
Dans la première partie de mon travail, j'ai préparé quatre catalyseurs différents à base d'oxydes de manganèse: une perovskite (LaMnO3), par voie sol-gel; un oxide simple (Mn2O3), par méthode rapide et un tamis moléculaire octahedrique (OMS-2) par deux méthodes de préparation différentes, via l'état solide (OMS) et la méthode hydrothermale (OMSh). Les propriétés physicochimiques de ces catalyseurs ont été caractérisées par diffraction des rayons X (DRX), adsorption-désorption de N2, analyses thermogravimétriques (ATD/ATG), analyses chimiques (ICP-OES) et réduction en température programmée (H2-RTP). Leurs performances catalytiques ont été évaluées dans la réaction d’oxydation du toluène. Trois cycles catalytiques consécutifs ont été réalisés pour chaque catalyseur afin de confirmer les performances. Afin d'évaluer la stabilité des catalyseurs dans des conditions réactionnelles, les performances catalytiques ont été étudiées sur des expériences de longue durée à température constante, pendant 24 h à 25% de conversion du toluène. Des tests d'oxydation du toluène sur un catalyseur de référence, type Pd/Al2O3 contenant 0,78% en poids de Pd, ont également été effectués à des fins de comparaison. Les caractéristiques cristallines détectées dans les modèles DRX sont bien compatibles avec la formation des structures désirées. Sur la base de leur surface spécifique et de leur réductibilité à basse température, les catalyseurs ont été classés comme suit : OMSs > Mn2O3 > OMS > LaMnO3. Cette tendance est en bon accord avec les performances observées dans l'élimination catalytique du toluène. Un modèle cinétique a été proposé et un bon accord a été obtenu lors de l'ajustement avec les données expérimentales. Dans la seconde partie de mon travail, des catalyseurs LaMnO3 (LM) avec un rapport molaire acide citrique (CA) sur nitrates métalliques (Mn et La) allant de 0,5 à 2 (LM 0,5 à LM 2) ont été synthétisés par méthode sol-gel citrate, afin d'étudier l'effet du rapport de l'acide citrique sur les propriétés physico-chimiques et les performances catalytiques. Les propriétés physicochimiques de ces catalyseurs ont été caractérisées par diffraction des rayons X (DRX), adsorption-désorption de N2 et par spectroscopie d'émission atomique de plasma à couplage inductif (ICP-AES). Sur des échantillons sélectionnés, des caractérisations supplémentaires par analyse thermogravimétrique et thermique différentielle (ATD/ATG), une réduction programmée en température par de l'hydrogène (H2-TPR) et une spectroscopie de photoélectrons X (XPS) ont été réalisées. Les résultats montrent que le rapport molaire acide citrique sur nitrates métalliques influence significativement le profil obtenu en ATD/ATG des solides non calcinés ainsi que les propriétés physico-chimiques des catalyseurs. Les caractéristiques cristallines détectées par DRX sont bien compatibles avec la formation de la phase perovskite LaMnO3. De petites caractéristiques de Mn2O3 ont été détectées dans les diagrammes de diffraction de tous les catalyseurs LM, à l'exception du rapport molaire élevé des nitrates CA / (Mn + La) (1,9 et 2,0). Inversement, des pics La2O3 sont observés pour des valeurs allant de 1,6 à 2, l'intensité la plus élevée étant détectée au rapport molaire égal à 2. Les performances catalytiques ont été évaluées dans l'oxydation du toluène en réalisant trois cycles catalytiques consécutifs pour atteindre des performances stables. Afin d'évaluer la stabilité des catalyseurs dans des conditions de réaction, des expériences à température constante ont été effectuées pendant 24 h à 17% de conversion du toluène. Les catalyseurs LM1.2, LM1.3 et LM1.5 ont montré les meilleures performances catalytiques en oxydation totale du toluène, tandis que LM1 et LM1.7 présentaient un comportement intermédiaire et LM0.8 était peu actif / In the first part of my work, I have prepared four different catalysts based on manganese oxides: a perovskite (LaMnO3), via sol-gel method; a simple oxide (Mn2O3), by rapid method and an Octahedral Molecular Sieve (OMS-2) by two different preparation methods, via solid state (OMSs) and hydrothermal method (OMSh). The physicochemical properties of these catalysts were characterized by X-ray diffraction (XRD), N2 adsorption–desorption, TGA/DTA, ICP-OES and H2-TPR. Their catalytic performances were evaluated in the oxidation of toluene. Three consecutive catalytic cycles were performed for each catalyst in order to reach steady state performances. In order to assess the stability of the catalysts under reaction conditions, the catalytic performances were studied upon long-term experiments running for 24 h at 25% of toluene conversion. Tests of toluene oxidation over a typical industrial catalyst, such as a commercial Pd/Al2O3 catalyst containing 0.78 wt% Pd, were also performed for comparison purposes. The crystalline features detected in the XRD patterns are well consistent with the formation of the desired structures. Based on their specific surface area and their low-temperature reducibility, the catalysts were ranked as follows: OMSs> Mn2O3> OMSh> LaMnO3. This trend was in good agreement with the performances observed in the catalytic removal of toluene. A kinetic model was proposed and a good agreement was obtained upon fitting with the experimental data. In the second part of my work, LaMnO3 (LM) catalysts with molar ratio of citric acid (CA) to metal nitrates (Mn and La) ranging from 0.5 to 2 (LM 0.5 to LM 2) were synthesized by citrate sol–gel method, in order to study effect of citric acid ratio on the physico-chemical properties and the catalytic performances. The physicochemical properties of these catalysts were characterized by X-ray diffraction (XRD), N2 adsorption–desorption and by inductively coupled plasma atomic emission spectroscopy (ICP-AES). Over selected samples, additional characterizations by thermogravimetric and differential thermal analysis (TGA/DTA), temperature-programmed reduction by hydrogen (H2-TPR) and X-ray photoelectron spectroscopy (XPS) were carried out. The results show that the molar ratio of citric acid to metal nitrates significantly influenced the TGA/DTA profile of gels along with the physico-chemical properties of the catalysts. The crystalline features detected by XRD are well consistent with the formation of LaMnO3 perovskite phase. Small features of Mn2O3 were detected in the diffraction patterns of all LM catalysts except for high CA/Mn+La nitrates molar ratio (1.9 and 2.0). Conversely, La2O3 peaks appeared for values ranging from 1.6 to 2, the highest intensity being detected at molar ratio equal to 2. The catalytic performances were evaluated in the oxidation of toluene, performing three consecutive catalytic cycles in order to reach steady-state performances. In order to assess the stability of the catalysts under reaction conditions, long-term experiments running for 24 h at 17 % of toluene conversion were carried out. The catalysts LM1.2, LM1.3 and LM1.5 showed the best catalytic performances in terms of toluene conversion, LM0.8 was poor performing, while LM1 and LM1.7 exhibited an intermediate behaviour
|
284 |
Conception et développement des réseaux de capteurs MEMS en silicium et en diamant pour la détection de vapeurs / Design and development of silicon and diamond MEMS sensors arrays for gas detectionPossas Abreu, Maira 05 December 2016 (has links)
Les systèmes multi-capteurs intelligents de gaz (ou nez électroniques), sont déjà déployés dans des domaines aussi divers que la parfumerie, l'industrie alimentaire, la surveillance de l'environnement et à des fins militaires et médicaux. La collaboration engagée dans le cadre du Projet Européen SNIFFER, s'est focalisée sur le développement d'un système type nez-électronique innovant basé sur des capteurs MEMS combinés à des bio-récepteurs olfactifs pour la détection de substances illicites. Dans un autre contexte et ce, dans une démarche interne à ESIEE-Paris, nous avons aussi choisi d'élargir le sujet à la conception d'un système multi-capteurs pour une application en détection de composés organiques volatils.Ainsi, dans la perspective d'une amélioration des technologies par l'utilisation de capteurs MEMS, cette thèse traite de la conception, la fabrication et la caractérisation de capteurs de type micro-poutre résonante en silicium et en diamant et également de la preuve de concept d'un système multi-capteur pour la détection de gaz. Si le choix du silicium en tant que matériaux pour la fabrication de nos capteurs a pour avantage l'énorme éventail de connaissances disponible, le diamant fait sa place dans le monde de la microtechnologie grâce à ses remarquables propriétés physiques et chimiques. Même si certaines études portant sur le développement de dispositifs et de procédés MEMS en diamant sont décrites dans la littérature, une comparaison entre les performances des deux matériaux pour le développement d'un même capteur n'a jamais été étudiée. En conséquence, cette thèse est axée sur l'utilisation de ces deux matériaux pour la conception de micro-poutres résonantes, afin d'établir des éléments de comparaison pour les deux technologies.Dans un premier temps, nous avons mis en place des procédés de micro-structuration du diamant développés auparavant dans notre laboratoire afin de les optimiser pour une fabrication totalement compatible avec les techniques de salle blanche et indépendante des variations des conditions de synthèse du diamant. Nous avons, pour la première fois, réalisé des micro-poutres en diamant avec des jauges en silicium polycristallin intégrées. Nous avons caractérisé le module d'Young du diamant en utilisant deux méthodes différentes aboutissant dans le cas le plus précis à la valeur de 1080 GPa. Ensuite, la sensibilité massique des poutres en silicium et en diamant fabriquées a été évaluée. Dans le meilleur des cas, et pour des fréquences de résonance très proches, les poutres en silicium présentent une sensibilité de 89 Hz/ng tandis que pour les poutres en diamant, la sensibilité s'élève à 212 Hz/ng. Nous avons également observé que pour des faibles variations de masse, l'impact de l'ajout de masse sur le coefficient de qualité des poutres était plus critique pour les structures en silicium.Finalement, une preuve de concept de l'utilisation du système multi-capteur à base de micro-poutres en silicium et en diamant pour la détection de composés organiques volatils a été mise en place. Nous avons démontré la détection de plusieurs composés dans des concentrations de l'ordre de la dizaine de ppm de manière totalement automatique et sans recours à des instruments de mesure. Les résultats de ces détections forment une base de données à partir de laquelle nous avons, par l'application de méthodes statistiques multivariées, abouti à la discrimination des composés testés / Smart multi-sensor systems for gas detection (or electronic noses), are already deployed in areas as diverse as cosmetics and food industry, environment monitoring and military and medical purposes. The ongoing collaboration within the European SNIFFER Project, focused on the development of an innovative electronic nose-like system based on MEMS sensors combined with olfactory bioreceptors for the detection of illicit substances. In another context and, within an internal approach to ESIEE-Paris, we have also chosen to expand the topic to design a multi-sensor system for application in volatile organic compounds detection.Thus, in view of improving these technologies through the use of MEMS sensors, this manuscript comprehensively investigates the design, fabrication and characterization of silicon and diamond resonant micro-cantilevers sensors, and also presents a proof of concept of a multi-sensor system for gas detection. To date, silicon has been used as a building block of micro sensors, whose features are very well known and argued extensively in the literature. On the other hand, diamond as a unique material in terms of its superior physical and chemical properties, has been received attention in microelectronics. Although the realization of diamond MEMS sensors has been presented before, it has been never compared to silicon MEMS gas sensors. Therefore, to establish elements of comparison for the two technologies, this thesis aimed to use these two competitive materials as a building block of micro-cantilever based MEMS gas sensors.Firstly, we set up specific micro-machining processes for the realization of diamond patterns that have been previously developed in our laboratory in order to optimize them for a fully clean room compatible manufacturing, independent of changes in diamond synthesis conditions. We have, for the first time, realized diamond micro-cantilevers with integrated polysilicon gauges. The Young's modulus of diamond was characterized using two different methods resulting in the best case of the value as 1080 GPa. Then, the mass sensitivity of silicon and diamond microcantilevers was evaluated. In the best case, for sensors presenting very similar resonant frequencies, the silicon microcantilever have a sensitivity of 89 Hz / ng whereas for the diamond microcantilever, the sensitivity is 212 Hz / ng. It has been also observed that the impact of adding mass on the beam quality factor was more critical to the silicon structures for low mass load cases.Finally, a proof of concept for the use of the multi-sensor system based on silicon and diamond micro-cantilevers for the detection of volatile organic compounds was established. We demonstrated the detection of several compounds in concentrations of the order of tens of ppm in a fully automatic way and without the use of measuring instruments. The results of these detections form a database from which we resulted in the discrimination of the compounds tested by applying multivariate statistical methods
|
285 |
How do plants defend themselves? : Study of the Tomato - Tuta absoluta pathosystem in interaction with nitrogen fertilization / Fonctionnement de la plante agressée : étude du pathosystème Tomate - Tuta absoluta en interaction avec la fertilisation azotéeCoqueret, Victoire 12 December 2017 (has links)
L’identification des réponses écophysiologiques des plantes est un préalable pour améliorer les défenses naturelles des plantes et réduire l’usage d’intrants chimiques dans les cultures. Les réponses des plantes vis-à-vis d’une agression herbivore fait intervenir des mécanismes de résistance et de tolérance. Les réponses à une agression d’une larve mineuse sont peu documentées contrairement aux insectes piqueurs ou broyeurs. L’objectif de ma thèse a été de caractériser les traits de réponse de la tomate vis-à-vis de Tuta absoluta afin de déterminer les réponses locales et systémiques en termes de composés solubles et volatils. Nous avons regardé les réponses de la tomate soumise à deux niveaux contrastés de la disponibilité en azote, sachant que l’azote est un levier sur lequel il est possible de s’appuyer pour modifier le niveau de défense des plantes. Nous avons travaillé sur la tomate, une solanacée cultivée en hydroponie et sujette à un ravageur Tuta absoluta. Notre stratégie de recherche s’est portée sur l’identification et la quantification des composés de défense solubles et volatils, et sur la détermination du pouvoir nutritionnel des tissus foliaires. Nous avons montré que la plante de tomate met en place une résistance induite par l’herbivore se traduisant par une augmentation de la concentration en acide chlorogénique, caffeoyl putrescine et tomatine localement au niveau de la zone parasitée et / ou de manière systémique dans les autres compartiments foliaires non infestés. Le rôle de ces molécules dans la défense de la tomate vis-à-vis de Tuta absoluta doit encore être confirmé. Nous avons montré aussi que la tomate met en place une défense indirecte contre Tuta absoluta, basée sur l’émission de composés volatils au voisinage des plantes. Nous avons identifié plusieurs nouveaux COVs synthétisés lors de l’herbivorie par Tuta absoluta (m-cymène, menthatriène, ß-cis-ocimène, ß-phellandrène, terpinolène, ß−caryophyllène, humulène). Parmi tous les COVs que nous avons identifiés, certains sont connus pour être émis en plus grande quantité lors d’une attaque herbivore et jouer un rôle dans l’attraction des insectes prédateurs ou la répulsion des femelles pondeuses. Ainsi, leur élicitation semble générique de l’herbivorie et pas spécifique de Tuta absoluta. La spécificité des interactions tomate - Tuta absoluta pourrait être renforcée par des analyses plus poussées en métabolomique, transcriptomique (expression de gènes RNAseq) et en s’intéressant aux voies de signalisation induite. Contrairement à ce qui était attendu, nos résultats montrent peu d’effets de la limitation en azote sur les réponses observées. Néanmoins, comme ce qui a été démontré précédemment, la limitation azotée impacte le développement larvaire. Mes travaux ont permis de renforcer l’hypothèse "trophique" du ralentissement du développement larvaire par la limitation en azote. Ainsi, la stœchiométrie du bol alimentaire est fortement modifiée et les larves doivent consommer plus de matières pour acquérir l’azote nécessaire à leur développement. Néanmoins nous ne pouvons pas écarter l’hypothèse "composés de défense". En effet, nous avons montré que les concentrations en composés phénoliques et tomatine et des émissions de COVs supposés être impliqués dans la défense constitutive, sont plus fortes en cas d’une limitation en azote. La diversité et la complémentarité des expérimentations permettront aux données acquises d’alimenter un modèle de fonctionnement de la plante agressée qui pourrait comporter une fonction de défense réactive à la nutrition azotée / The identification of ecophysiological responses of plants is a prerequisite for improving the natural defences of plants and reducing the use of chemical inputs in crops. Plant responses to herbivorous attack involve defence and tolerance mechanisms. Plant responses to a leafminer larva are pourly documented, in contrast to chewing and piercing insects. The objective of my Ph.D. was to characterize the tomato trait responses to Tuta absoluta herbivory in order to determine the local and systemic responses in terms of soluble and volatile compounds. We looked at the responses of tomatoes subjected to two contrasting levels of nitrogen availability, knowing that nitrogen is a lever to promote the basal plant defence level. We worked on tomato, a Solanaceae, grown in hydroponics and subjected to Tuta absoluta. Our research strategy has focused on identifying and quantifying soluble and volatile defence compounds and determining the nutritional value of foliar tissues. We have shown that tomatoes establish an induced- resistance against the herbivore, which results in a concentration increase of chlorogenic acid, caffeoyl putrescine and tomatine locally at the level of the parasite zone and / or systemically in the others non-infested foliar compartments. The defence role of these molecules on Tuta absoluta has yet to be confirmed. We have also shown that tomatoes set up an indirect defence against Tuta absoluta, based on the emission of volatile compounds in the vicinity of plants. We have identified several new herbivore-induced VOCs (m-cymene, menthatriene, ß-cis-ocimene, ß-phellandrene, terpinolene, ß−caryophyllene, humulene). Some of the identified VOCs are known to be emitted in greater quantities during a herbivorous attack and to play a role in attracting predatory insects or repelling egg-laying females. Thus, their elicitation seems generic to herbivory and not specific to Tuta absoluta. The specificity of tomato - Tuta absoluta interactions could be enhanced by further analysis in metabolomics, transcriptomics (expression of RNAseq genes) and by investigating the induced signaling pathways. Contrary to what was expected, our results show little effect of the nitrogen limitation on the observed responses. Nevertheless, as demonstrated previously, nitrogen restriction affects larval development. My work has reinforced the “trophic“ hypothesis of slowing larval development by a limited nitrogen availability. Thus, the stoichiometry of the food bowl is highly modified and the larvae have to consume more material to acquire the nitrogen necessary for their development. Nevertheless, we can not exclude the hypothesis “compounds of defence“. Indeed, we have shown that the concentrations of phenolic compounds and tomatine and of the VOC emission supposed to be involved in the constitutive defence are increased in the case of nitrogen limitation. The diversity and complementarity of the experiments will allow the acquired data to feed a functional model of the attacked plant. This model might include plant nitrogen regimes as a reactive plant defence factor
|
286 |
Influência dos compostos orgânicos voláteis no potencial de formação do ozônio troposférico na Grande Vitória-ESGalvão, Elson Silva 06 June 2014 (has links)
Submitted by Elizabete Silva (elizabete.silva@ufes.br) on 2015-11-23T19:08:09Z
No. of bitstreams: 2
license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5)
INFLUÊNCIA DOS COMPOSTOS ORGÂNICOS VOLÁTEIS NO POTENCIAL DE FORMAÇÃO DO OZÔNIO TROPOSFÉRICO NA GRANDE VITÓRIA-ES.pdf: 3636611 bytes, checksum: 18bc0a9ce6ff16e16830e30e01febabc (MD5) / Approved for entry into archive by Morgana Andrade (morgana.andrade@ufes.br) on 2016-01-05T10:15:50Z (GMT) No. of bitstreams: 2
license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5)
INFLUÊNCIA DOS COMPOSTOS ORGÂNICOS VOLÁTEIS NO POTENCIAL DE FORMAÇÃO DO OZÔNIO TROPOSFÉRICO NA GRANDE VITÓRIA-ES.pdf: 3636611 bytes, checksum: 18bc0a9ce6ff16e16830e30e01febabc (MD5) / Made available in DSpace on 2016-01-05T10:15:50Z (GMT). No. of bitstreams: 2
license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5)
INFLUÊNCIA DOS COMPOSTOS ORGÂNICOS VOLÁTEIS NO POTENCIAL DE FORMAÇÃO DO OZÔNIO TROPOSFÉRICO NA GRANDE VITÓRIA-ES.pdf: 3636611 bytes, checksum: 18bc0a9ce6ff16e16830e30e01febabc (MD5)
Previous issue date: 2014 / CNPQ / Neste estudo, foi avaliado o potencial de formação do ozônio troposférico (PFO) a partir da influência dos compostos orgânicos voláteis (COV) presentes na atmosfera da Região Metropolitana da Grande Vitória (RMGV) entre os períodos de 05/02/2013 a 05/04/2013 e entre 16/05/2013 a 21/06/2013. Cada espécie de COV reativo possui um determinado potencial na formação do ozônio, por isso, a importância no conhecimento dessas espécies presentes na atmosfera local é de suma importância na proposição de medidas de controle da poluição do ar. Por meio de amostradores passivos um total de 96 amostras foram coletadas em três estações da rede de monitoramento da qualidade do ar (RAMQAr) da RMGV, localizadas nos bairros Laranjeiras, Enseada do Suá e Ibes. A caracterização qualitativa e quantitativa dos COV possibilitou quantificar o PFO da região através do método de escala de reatividade máxima por incremento (MIR) proposta por Carter (1994). Os resultados indicaram que o grupo de COV predominante na RMGV é dos ácidos orgânicos, seguido pelos álcoois e aromáticos substituídos. Entre os COV com maior potencial de formação do ozônio, os compostos undecano, tolueno, etilbenzeno e o,m,p-xileno são os de maior abundância na RMGV, apresentando médias, respectivamente, de 0,855 μg m-3, 0,365 μg m-3 , 0,259 μg m-3 e 0,289 μg m-3 no período entre 16/05/2013 a 21/06/2013. Os resultados ainda indicaram que os BTEX, grupo constituído por benzeno, tolueno, etilbenzeno e o,m,p-xilenos, encontraram-se abaixo dos valores considerados prejudiciais a saúde da população na RMGV. O PFO na RMGV calculado a partir de todos os compostos do grupo COV precursores foi de 22,55 μg m-3 para o período de 05/02/2013 a 05/04/2013 e de 32,11 μg m-3 para o período de 16/05/2013 a 21/06/2013, sendo que, os compostos, tolueno e o-xileno foram responsáveis por aproximadamente 37% de todo o PFO produzido a partir do grupo COV precursores. Uma avaliação revelou que o valor geral da razão COV/NOx para a RMGV foi de aproximadamente 1,71, indicando que a região apresenta uma condição COV-limitante na produção do ozônio. Portanto, a adoção de medidas apenas para remoção de NOx da atmosfera da RMGV poderá favorecer as reações entre o OH e os COV, formando radicais que possibilitam regenerar o NO2 e favorecendo o aumento da taxa líquida de produção do ozônio na região. / In the present study, the ozone forming potential (OFP) from volatile organic compounds (VOCs) in the atmosphere of Metropolitan Region of Grande Vitória (RMGV) has been studied on the periods between 02/05/2013 to 04/05/2013 and 05/16/2013 to 06/21/2013. Each species of VOC has a particular reactivity on ozone forming potential, so the knowledge of these species in the local atmosphere is of great importance in proposing measures to control of air pollution. Passive samplers were installed at three of air quality monitoring stations (RAMQAr) of RMGV, and a total of 96 samplings were collected between the two sampling periods. By the characterization and quantification of VOC was possible to quantify the OFP applying the scale of maximum incremental reactivity (MIR) proposed by Carter (1994). The results indicated that the predominant group of VOCs in the RMGV is the organic acids, followed by alcohols and substituted aromatics. Among the VOCs with the greatest OFP, the undecane, toluene , ethylbenzene and m, p-xylene compounds are the most abundant in RMGV, presenting the means of 0,855 μg m-3, 0,365 μg m-3 , 0,259 μg m-3 and 0,289 μg m-3, respectively, on the period 05/16/2013 to 06/21/2013. The results also indicated that the BTEX group consisting of benzene, toluene, ethylbenzene and m,p-xylenes are below of the limits considered harmful to the health of the population in RMGV . The ozone forming potential in RMGV calculated from all the precursors VOC group was 22.55 μg m-3 in summer period and 32.11 μg m-3 in the winter period. The toluene and o-xylene compounds are responsible for approximately 37 % of all OFP produced from precursors VOC group. The assessment of the VOC/NOx ratio revealed that the overall value of that ratio in RMGV is approximately 1.71, indicating that the region has a VOC-limiting condition for the production of ozone. Therefore, the adoption of measures only to remove NOx from the atmosphere of RMGV could favor reactions between OH and VOC, forming radicals that enable regenerate NO2 increasing the net rate of ozone production in the region.
|
287 |
Determinação de clorobenzenos em água por cromatografia de fase gasosa com headspace / Determination of chlorobenzenes in water by gas chromatography headspaceMargarida Maria Sartori Tavares 29 February 2012 (has links)
As preocupações com o meio ambiente em particular com a água, adquirem especial importância, porque as demandas estão se tornando cada vez maiores, sob o aspecto crescente da população e das atividades industriais. Quando se fala em água subterrânea, a primeira ideia que surge é que ela seja potável. Mas nem sempre isso é uma verdade. Em área urbana, os crescentes números de problemas devido a contaminação, na maioria das vezes por vazamentos de combustíveis oriundos dos tanques de armazenamento dos postos de gasolina. Sem falar nas indústrias que também oferecem potencial risco de contaminação para esses corpos hídricos e são pouco divulgadas. O presente trabalho tem como foco determinar os compostos clorobenzenos por cromatografia de fase gasosa com headspace (CG-HS) em matriz água e validar a metodologia. A metodologia usada neste estudo foi cromatografia de fase gasosa com headspace (CG HS), por ser uma técnica excelente e sensível e é utilizada para determinar compostos voláteis em baixas concentrações. Os dados obtidos foram tratados estatisticamente de modo avaliar a seletividade, os limites de detecção e quantificação, a faixa linear de trabalho, a linearidade e a recuperação. As recuperações variam de 80 a 110%, os coeficientes de variação obtidos foram menor que 20%, todas as substâncias estudadas apresentaram linearidade na faixa de trabalho de 0,8 a 100g.L-1.
Foram estudadas 10 amostras de água subterrânea do Município do Rio de Janeiro e nas amostras analisadas foram encontrados todos os compostos em estudo, com faixa de concentração: monoclorobenzeno (<0,8 a 2,988g.L-1); 1,3-diclorobenzeno (<0,8 a 23,067g.L-1); 1,4-diclorobenzeno (nd a 16,160g.L-1); 1,2-diclorobenzeno (<0,8 a 48,685g.L-1); 1,3,5-triclorobenzeno (<0,8 a 21,900g.L-1); 1,2,4-triclorobenzeno (1,007 a 183,808g.L-1) e 1,2,3-triclorobenzeno (<0,8 a 126,886g.L-1) / The concerns with the environment, in particular with water, acquire special importance, because the demands become ever higher, under the growth of the population and industrial activities aspects. When speaking about underground water, the first notion that comes to mind is that it is potable water. But thats not always a true. In urban areas, the increasing numbers of problems due to contamination, is caused, most of time, by leaking gas tanks of gas stations. Not to mention industries that also offer the potential risk of contamination of these water bodies and that less divulged. The present work is focused in determining chlorobenzenes by headspace gas chromatography (HS-GC) in the water and validating its methodology. The methodology used in this work was headspace gas chromatography (HS-CG), because of its excellence technique and sensitive, applied for determining low concentrations volatile compounds. The data was statistically treated so to evaluate the selectivity, quantitation and detection limits, work range linearity, linearity and recovery. The recoveries vary between 80 to 110%, the variation obtained were less than 20%, all compounds present linearity in the work range 0,8 of 100g.L-1. .
Ten samples of underground water of Rio de Janeiro were tested, and all the samples contained the studied compounds, as and range concentration: chlorobenzene (<0,8 a 2,988g.L-1), 1,3-dichlorobenzene (<0,8 a 23,067g.L-1), 1,4-dichlorobenzene (nd a 16,160g.L-1), 1,2-dichlorobenzene (<0,8 a 48,685g.L-1), 1,3,5-trichlorobenzene (<0,8 a 21,900g.L-1), 1,2,4-trichlorobenzene (1,007 a 183,808g.L-1) and 1,2,3-trichlorobenzene (<0,8 a 126,886g.L-1)
|
288 |
Avaliação das concentrações de BTEX em ambiente indoor: estudo de caso da sala de spinning de uma academia de ginástica Rio de Janeiro / RJ. / Assement of concentration of BTEX in indoor enviroment: case study of a spinnin room - Rio de Janeiro, RJ.Mônica Domingues Monteiro 16 March 2011 (has links)
Muitos dos locais onde as atividades são realizadas nas academias de ginásticas são salas pequenas e fechadas com sistema de climatização artificial, freqüentados por um grande número de alunos realizando seus exercícios e profissionais auxiliando as atividades. Com isso, há uma intensa transpiração desses indivíduos, uma freqüente rotina de limpeza do piso e de equipamentos com pequenos intervalos, possibilitando a alterações da qualidade do ar indoor. O presente trabalho busca mostrar as tendências de variações nos valores das concentrações dos poluentes atmosféricos BTEX em ambiente indoor, especificamente na sala de spinning de uma academia de ginástica do Rio de Janeiro. Para o monitoramento da qualidade do ar foram utilizados cartuchos de carvão ativado SKC, acoplado a uma bomba KNF com vazão de 1l min. Para a extração de cada amostra foi feita a análise cromatográfica com cromatógrafo a gás modelo 6890 acoplado a um espectrômetro de massa modelo 5973 da marca Agilent. Foram analisadas 34 amostras coletadas na salas de spinning durante as aulas com atividades aeróbicas, o que intensificava a respiração dos indivíduos, possibilitando uma maior inalação destes COVs. Em contrapartida, também foram coletadas 5 amostras outdoor, 4 delas pareadas indoor/ outdoor para uma análise comparativa das concentrações destes poluentes. Dentre os compostos orgânicos voláteis analisados, o tolueno é o BTEX mais abundante obtido neste trabalho, representando 81% destes COVs indoor. Todas as amostras medidas em pares indoor/ outdoor tiveram concentrações maiores no interior, exceto para o benzeno no dia 3/12/2010. Simples atividades usualmente realizadas pelo homem, como a inserção de piso emborrachado, manutenção do sistema de climatização artificial, e limpeza podem alterar o ar indoor. As conclusões alcançadas após as medições das concentrações de BTEX foram de que o ar indoor estava mais poluído do que o outdoor. Este monitoramento da qualidade do ar indoor ainda é escasso no Brasil. Alguns esforços tem sido feito em relação a ambientes confinados como a Portaria n˚3523 do Ministério da Saúde, regulamentando o controle dos ambientes climatizados e a Resolução n˚9 da Agência Nacional de Vigilância Sanitária, além da Resolução CONAMA n ˚3 estabelecendo padrões de qualidade do ar para alguns compostos químicos, porém muitos compostos químicos ainda não são legislados ou não possuem a devida atenção, não sendo suficientes para contemplar a complexidade do assunto / In many gyms work-out activities take place in small enclosed rooms where the climate is controlled artificially. Normally, those rooms are full of students doing their workout and trainers helping them. Intense human transpiration requires a frequent floor and equipment cleaning routine. This routine, performed at short intervals can affect the indoor air quality. This study is aimed at showing varying concentration levels of the BTEX air pollutant at a gym in Rio de Janeiro, Brazil, specifically the spinning room. To monitor the air quality, activated charcoal cartridges (SKC) were used, coupled to a KNF pump with a flow rate of 1l min. For the extraction of each sample, a gas chromatographic analysis machine model 6890 was used coupled to an Agilent mass spectrometer model 5973. We analyzed a total of 34 air samples collected in the spinning room during active aerobic classes; the increased respiration from the subjects allow for a greater inhalation of VOCs. In Contrast, five samples were also collected outdoors; four of them were paired indoor / outdoor for comparative analysis of these pollutants. Among the volatile organic compounds analyzed, toluene was the most abundant BTEX found in this study, representing 81% of indoor VOCs. In all the indoor / outdoor paired samples, the concentration was higher in the interior samples, with one exception, benzene on 3/12/2010. Simple changes that can easily be done by man, such as the installation of rubberized flooring, regular maintenance of the air acclimatization equipment, and general cleanliness can greatly affect the indoor air quality. The conclusion achieved after looking at the BTEX measurements was that the indoor air was more polluted than the air outdoors. This air quality monitoring is still scarce in Brazil. Some efforts have been made in relation to confined spaces such as Ordinance n˚ 3523 from the Ministry of Health, which regulates the air of air-conditioned environments and Resolution n˚ 9 of the National Agency for Sanitary Vigilance, as well as Resolution CONAMA n˚ 3 by setting standards for air quality for some chemical compounds, unfortunately many chemical compounds are not yet legislated or receive proper attention in this matter, therefore not giving this indoor air pollution matter enough grounds to address the complexity of the subject
|
289 |
Avaliação das concentrações de BTEX em ambiente indoor: estudo de caso da sala de spinning de uma academia de ginástica Rio de Janeiro / RJ. / Assement of concentration of BTEX in indoor enviroment: case study of a spinnin room - Rio de Janeiro, RJ.Mônica Domingues Monteiro 16 March 2011 (has links)
Muitos dos locais onde as atividades são realizadas nas academias de ginásticas são salas pequenas e fechadas com sistema de climatização artificial, freqüentados por um grande número de alunos realizando seus exercícios e profissionais auxiliando as atividades. Com isso, há uma intensa transpiração desses indivíduos, uma freqüente rotina de limpeza do piso e de equipamentos com pequenos intervalos, possibilitando a alterações da qualidade do ar indoor. O presente trabalho busca mostrar as tendências de variações nos valores das concentrações dos poluentes atmosféricos BTEX em ambiente indoor, especificamente na sala de spinning de uma academia de ginástica do Rio de Janeiro. Para o monitoramento da qualidade do ar foram utilizados cartuchos de carvão ativado SKC, acoplado a uma bomba KNF com vazão de 1l min. Para a extração de cada amostra foi feita a análise cromatográfica com cromatógrafo a gás modelo 6890 acoplado a um espectrômetro de massa modelo 5973 da marca Agilent. Foram analisadas 34 amostras coletadas na salas de spinning durante as aulas com atividades aeróbicas, o que intensificava a respiração dos indivíduos, possibilitando uma maior inalação destes COVs. Em contrapartida, também foram coletadas 5 amostras outdoor, 4 delas pareadas indoor/ outdoor para uma análise comparativa das concentrações destes poluentes. Dentre os compostos orgânicos voláteis analisados, o tolueno é o BTEX mais abundante obtido neste trabalho, representando 81% destes COVs indoor. Todas as amostras medidas em pares indoor/ outdoor tiveram concentrações maiores no interior, exceto para o benzeno no dia 3/12/2010. Simples atividades usualmente realizadas pelo homem, como a inserção de piso emborrachado, manutenção do sistema de climatização artificial, e limpeza podem alterar o ar indoor. As conclusões alcançadas após as medições das concentrações de BTEX foram de que o ar indoor estava mais poluído do que o outdoor. Este monitoramento da qualidade do ar indoor ainda é escasso no Brasil. Alguns esforços tem sido feito em relação a ambientes confinados como a Portaria n˚3523 do Ministério da Saúde, regulamentando o controle dos ambientes climatizados e a Resolução n˚9 da Agência Nacional de Vigilância Sanitária, além da Resolução CONAMA n ˚3 estabelecendo padrões de qualidade do ar para alguns compostos químicos, porém muitos compostos químicos ainda não são legislados ou não possuem a devida atenção, não sendo suficientes para contemplar a complexidade do assunto / In many gyms work-out activities take place in small enclosed rooms where the climate is controlled artificially. Normally, those rooms are full of students doing their workout and trainers helping them. Intense human transpiration requires a frequent floor and equipment cleaning routine. This routine, performed at short intervals can affect the indoor air quality. This study is aimed at showing varying concentration levels of the BTEX air pollutant at a gym in Rio de Janeiro, Brazil, specifically the spinning room. To monitor the air quality, activated charcoal cartridges (SKC) were used, coupled to a KNF pump with a flow rate of 1l min. For the extraction of each sample, a gas chromatographic analysis machine model 6890 was used coupled to an Agilent mass spectrometer model 5973. We analyzed a total of 34 air samples collected in the spinning room during active aerobic classes; the increased respiration from the subjects allow for a greater inhalation of VOCs. In Contrast, five samples were also collected outdoors; four of them were paired indoor / outdoor for comparative analysis of these pollutants. Among the volatile organic compounds analyzed, toluene was the most abundant BTEX found in this study, representing 81% of indoor VOCs. In all the indoor / outdoor paired samples, the concentration was higher in the interior samples, with one exception, benzene on 3/12/2010. Simple changes that can easily be done by man, such as the installation of rubberized flooring, regular maintenance of the air acclimatization equipment, and general cleanliness can greatly affect the indoor air quality. The conclusion achieved after looking at the BTEX measurements was that the indoor air was more polluted than the air outdoors. This air quality monitoring is still scarce in Brazil. Some efforts have been made in relation to confined spaces such as Ordinance n˚ 3523 from the Ministry of Health, which regulates the air of air-conditioned environments and Resolution n˚ 9 of the National Agency for Sanitary Vigilance, as well as Resolution CONAMA n˚ 3 by setting standards for air quality for some chemical compounds, unfortunately many chemical compounds are not yet legislated or receive proper attention in this matter, therefore not giving this indoor air pollution matter enough grounds to address the complexity of the subject
|
290 |
Étude d'un procédé propre couplant l'absorption gaz/liquide microstructurée avec la distillation pour le traitement d'air chargé par un Composé Organique Volatil / Study of a clean process coupling microstructured gas/liquid absorption with distillation for treament of air contaminated by a volatil organic compoundMhiri, Neïla 26 June 2009 (has links)
Cette thèse porte sur le développement d’un procédé industriel propre constitué par un couplage absorption-distillation, destiné aux traitements d’effluents gazeux chargés par un Composé Organique Volatil (COV). L’absorption est effectuée dans un microabsorbeur à film tombant. La première étape de ce travail consiste à caractériser le transfert de matière dans cet appareil, lors de l’absorption gaz/liquide du Perchloroéthylène (PCE) par le Di(2-EthylHexyl)Adipate (DEHA). Les expériences ont montré la faisabilité et l’intérêt de cette opération dans un micro-contacteur. En effet, les efficacités d’épuration obtenues sont comparables à celles des procédés classiques (jusqu’à 97%) et les quantités de solvant d’absorption utilisées sont très faibles. Une étude paramétrique a révélé une intensification significative du transfert de matière, côté gaz, et un gain en compacité, à la suite de la minimisation de l’épaisseur de la veine de gaz (2mm) et du débit de la phase gazeuse. Cette étude a également montré la limite du microabsorbeur à traiter de grands débits de gaz avec de bonnes efficacités, causée par la faible influence qu’exerce la vitesse du gaz sur le coefficient de transfert de matière. Ce comportement a été expliqué, grâce à des simulations en 2D, par une dispersion importante des profils de concentration indiquant une limitation diffusionnelle. Cette dernière provient essentiellement du régime laminaire lisse et de la petite taille caractérisant ce type de micro-procédé. Pour s’affranchir de cette limitation, la turbulence doit être favorisée dans le gaz. La deuxième étape de ce travail concerne l’extrapolation du microabsorbeur de laboratoire à l’échelle industrielle des PME/PMI, basée sur le concept du numbering-up. A l’issu des calculs, un absorbeur microstructuré efficace (95%), et compact (surface occupée ˜ 0,5m2) a été développé. Pour rentabiliser son fonctionnement, un recyclage par distillation flash du solvant d’absorption a été étudié. Les résultats obtenus ouvrent la voie sur une technique d’épuration prometteuse, qui nécessite néanmoins une validation théorique et expérimentale du couplage absorbeur-distillateur / This project focuses on the development of an industrial process, in which a coupled absorption/distillation unit is developed to treat gaseous effluents contaminated by a Volatile Organic Compound (VOC). Absorption is performed in a falling film microabsorber. The first stage of this work consists in characterizing the mass transfer in this device. The gas/liquid absorption of Perchloroethylene (PCE) by Di (2-EthylHexyl) Adipate (DEHA) is used as test case. Experiments showed the feasibility and the benefit of this separation process operated in a micro-contactor. Indeed, the purification efficiencies obtained are comparable to those of conventional processes (97%). Moreover, the required absorption solvent quantities are very low. A parametric study revealed significant mass transfer intensification on gas side and a gain in compactness due to the minimization of gas cavity thickness (2mm) and gas flowrate. This study also showed the limits of microabsorbers to handle large gas flowrates with good efficiencies, due to a low influence of gas velocity on the mass transfer coefficient. This behaviour was explained, thanks to 2D simulations, by a significant dispersion of concentration profiles, which indicates a diffusion limitation. The latter comes mainly from smooth laminar flow and the small size, a typical characteristic of micro-processes. To overcome this limitation, turbulence should be promoted in the gas. The second stage of this work concerns the microabsorber extrapolation from laboratory scale to industrial SMEs, based on the numbering-up concept. Calculations predict high throughputs with a microstructured absorber of competitive efficiency (95%) and high compactness (area occupied ˜ 0.5 m2). For profitable operation, solvent absorption recycling by a flash distillation is studied. The results lead to a promising treatment technique, which still requires a theoretical and experimental validation of the coupled absorber-distiller unit
|
Page generated in 0.0578 seconds