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Airborne measurements of pollutants in the sphere of influence of the Radford Army Ammunition PlantMoore, James D. January 1982 (has links)
Nitrogen oxides, sulfur dioxide, ozone, light scattering and relative humidity were measured in the sphere of influence of the Radford Army Ammunition Plant using an airborne platform. Data were obtained on twelve days between May and July 1980 and were used to map the upwind-downwind pollutant concentrations around the arsenal.
Results of this investigation indicate that an airborne platform can be used successfully in characterizing pollutant parameters in the sphere of influence of an area source. Results also indicate the complexity of NO-NO<sub>2</sub>-O<sub>3</sub> cycle when hydrocarbons and sulfur dioxide are present.
Benefits of this type of study may prove useful for the technical and administrative decision making processes of regulatory agencies and munitions manufacturing personnel. / M. S.
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[pt] AVALIAÇÃO DA QUALIDADE DO AR NO RÉVEILLON EM COPACABANA, RIO DE JANEIRO / [en] NEW YEAR S AIR QUALITY ASSESSMENT IN COPACABANA, RIO DE JANEIROANA CAROLINA DE OLIVEIRA CARVALHO 18 October 2022 (has links)
[pt] O Réveillon em Copacabana, no Rio de Janeiro, na virada do dia 31/12 para
o dia 01/01, ocorre com a queima de 17 a 25 t de fogos de artifícios com duração
entre 12 a 17 minutos. Estudos realizados em outros países durante comemorações
com queima de fogos mostram um aumento significativo de alguns poluentes no ar.
Este estudo avaliou a qualidade do ar em Copacabana durante as comemorações do
ano novo de 2015 a 2020, considerando as concentrações do MP10, SO2, CO e O3
amostrados na estação automática. Pelo teste de Shapiro-Wilk, uma distribuição
assimétrica no banco de dados foi observada, e através do teste não paramétrico as
concentrações diárias entre os dias 31 de dezembro e 01 de janeiro foram testadas.
A composição química MP2,5 amostrado na estação semiautomática de Copacabana
em 2019, foi realizada através das técnicas analíticas de cromatografia de íons (CI)
e espectrometria de massa por plasma acoplado indutivamente (ICP-MS), traduzido
do inglês, inductively coupled plasma mass spectrometry. Durante o ano de 2019,
as concentrações diária e anual do MP(2,5) não ultrapassaram os padrões nacionais de
qualidade do ar, mas segundo os padrões recomendados pela OMS, a qualidade do
ar esteve inapropriada. As concentrações elementares e iônicas determinadas por
ICP-MS e CI indicaram espécies características de fontes veiculares e naturais. Em
01 de janeiro de 2020 a concentração dos íons Cl(-) e Na(+), foi atribuída ao spray marinho, e a ausência dos ânions C2H3COO(-), CH2(COO)2(2-) CHOO(-) e C2O4(2-) foi atribuída à diminuição da circulação urbana. / [en] New Year s Eve in Copacabana, Rio de Janeiro, at the turn of 12/31 to 01/01,
takes place with the burning of 17 to 25 t of fireworks lasting between 12 and 17
minutes. Studies carried out in other countries during celebrations with fireworks
show a significant increase in some pollutants in the air. This study evaluated the
air quality in Copacabana during the New Year celebrations from 2015 to 2020,
considering the concentrations of PM10, SO2, CO and O3 sampled at the automatic
station. By the Shapiro-Wilk test, an asymmetry distribution in the database was
observed, and through the non-parametric test the daily concentrations between
December 31st and January 1st were tested. The chemical composition PM2.5
sampled at the semi-automatic station in Copacabana in 2019 was performed using
analytical techniques of ion chromatography (IC) and inductively coupled plasma
mass spectrometry (ICP-MS). During the year 2019 concentrations of PM2.5 not
exceeded to national air quality standards, but according to the standards
recommended by the WHO, the air quality was inappropriate. The elemental and
ionic concentrations determined by ICP-MS and CI indicated species characterized
from vehicular and natural sources. On January 1, 2020, the concentration ions of
Cl(-)and Na(+) was attributed to marine spray, and the absence of the anions C2H3COO(-), CH2(COO)2(2-) CHOO(-) e C2O4(2-) was attributed to the lowest urban circulation.
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An indoor air quality case study: the diagnosis and remediation of Cowgill Hall's IAQ problemHilten, Craig Steven 05 September 2009 (has links)
This case study documents the entire indoor air quality (IAQ) problem experienced by the students, faculty and staff of Cowgill Hall on the campus of Virginia Polytechnic Institute and State University from August 1987 to August 1988, recommends a general IAQ solution process and makes several specific suggestions to prevent the reoccurrence of the problem in Cowgill Hall. Background information on Cowgill Hall and the indoor air quality issue are also provided.
This document is addressed to students of architecture, engineering and related disciplines. It emphasizes the growing importance and possible repercussions of their design decisions on the total environment; both in and out of doors. / Master of Science
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An evaluation of sensory comfort components of survey questionnaires used for indoor environment problems in buildingsHart-Schubert, Patrice 07 October 2005 (has links)
The efficacy of indoor environment evaluation is, in part, a function of the reliability and validity of the different measures used. This thesis presents results of a study, conducted in a building without known problems, which compares the reliability and validity of sensory comfort components from three well-known survey questionnaires. A review of literature reveals that sensory comfort theory draws upon many disciplines including, hedonics, psychometrics, and olfaction theory. The fundamental domains thermal, air quality, lighting, and acoustics and their dimensions are identified. The conceptual model integrates these theories underlying human response to sensory comfort.
The research questions involved in the selection of survey questionnaires are explored by examining sixteen indoor environment survey questionnaires. A meta-evaluation reveals that these questionnaires have three major functions, proactive, reactive, and re-evaluative studies.
Finally, the methods used to analyze survey questionnaires for reliability and validity are examined. An analysis of variance shows that the order in which questions were presented did not affect responses. The reliability of the measures tested ranged from poor to good. Examination of content and face validity by expert and untrained judges demonstrates inconsistencies in common or accepted meanings of the measures considered in evaluating the indoor environment. Analysis of construct validity indicates that not all survey questionnaire variables were categorized under their expected dimensions.
Contrary to advice found in the literature, this thesis suggests that the practice of combining items from different questionnaires is problematic. Finally, in buildings with known problems we can expect a relatively high degree of reliability and validity. However, the utility of such questionnaires in inventorying and assessing buildings without known problems will prove to be questionable. / Master of Urban and Regional Planning
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The response of 12 clones of eastern white pine (Pinus strobus L.) to ozone and nitrogen dioxideNicholson, Christopher Robin 12 June 2010 (has links)
Grafts were made using 2-0 rootstock and scion from 12 ortets of eastern white pine (Pinus strobus L.) growing at the Radford Army Ammunition Plant (RAAP). The 12 ortets represented 4 symptom severity classes (3 ortets/class) ranging from trees with > 25% of their crowns exhibiting necrotic tipburn (Class I) to those with healthy crowns (Class IV). Grafts were made in spring 1976 and ramets were grown in a greenhouse drawing charcoal filtered air. Each treatment was performed twice, on separate days for a total of 10 ramets/clone/ treatment. Five ramets/clone were used in each 6 hour treatment. The current years growth was 7-10 weeks old when treated. The treatments were as follows: 1) 0₃-10 pphm, 2) 0₃-30 pphm, 3) NO₂-10 pphm, 4) NO₂-30 pphm, 5) 0₃-10+NO₂ -10 pphm, 6) 0₃-10+NO₂ -30 pphm, 7) no pollutant. The fumigation chamber was a modified open-top field chamber located indoors. Environmental conditions during the 14 treatments averaged: 26 C, 64% RH, and 16 Klux. The ramets were evaluated prior to fumigation and then 2, 7, and 14 days thereafter for visible symptoms. The overall injury was generally light with only 11% of the clone treatment combinations exhibiting injury on > 25% of the needle fascicles. Clones I-1 and I-2 were the most sensitive clones while clones III-1, IV-2 and to a lesser degree clones III-3 and IV-1 were tolerant. These results agree with field ratings of eastern white pine sensitivity at the RAAP and provide the first step in the development of an air pollution bioindicator system at the installation. / Master of Science
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Computerized feedback control of an environmental chamberRamachandran, Gurumurthy 12 June 2010 (has links)
Most existing environmental chambers cannot simulate dynamically changing environmental conditions. Hence there is a need for a dynamically controlled artificial environment for plant studies. This project demonstrates the control of temperature, humidity and SO₂ concentration in a Continuous Stirred Tank Reactor (CSTR) system using feedback control through a computer.
An IBM-PC was connected to the measuring instrumentation and control equipment through a data acquisition and control system. Temperature and humidity were controlled by an ON-OFF control scheme. Sulfur dioxide concentration was controlled by means of a modified proportional derivative control algorithm.
The system is capable of achieving a wide range of temperatures (7°C to 40°C), humidities (30% to 97%), and SO₂ concentrations. Temperature is maintained within ±0.5°C of the desired value and humidity is controlled within ±4% of the desired value. Sulfur dioxide concentration is kept within ±10% of the desired concentration.
It was found that as humidity increases, the supply rate of SO₂ must be increased to maintain a given concentration. Software response time is slow. This causes time lags in the modification of the controlled parameters to achieve desired values. The heating and cooling characteristics of the system can be improved by better insulation of the chamber walls. The system demonstrates that computerized feedback control is practical for application to controlling environmental parameters in a fumigation chamber. / Master of Science
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Engineering the Environment: Regulatory Engineering at the U.S. Environmental Protection Agency, 1970-1980Lee, Jong Min 05 September 2013 (has links)
My dissertation addresses how engineers, scientists, and bureaucrats generated knowledge about pollution, crafted an institution for environmental protection, and constructed a collective identity for themselves. I show an important shift in regulators\' priorities, from stringent health-based standards to flexible technology-based ones through the development of end-of-pipeline pollution control devices, which contributed to the emergence of economic incentives and voluntary management programs. Drawing on findings from archival documents, published sources, and oral history interviews, I examine the first decade of the EPA amid constant organizational changes that shaped the technological and managerial character of environmental policy in the United States. Exploring the EPA\'s internal research and development processes and their relationship with scientific and engineering communities sheds light on how the new fields of environmental engineering and policy were co-produced in the 1970s.
I argue that two competing approaches for environmental management, a community health approach and a control technology approach, developed from EPA\'s responses to bureaucratic, geographical, and epistemic challenges. I focus on researchers and managers from the Office of Research and Development at Research Triangle Park, North Carolina, as they were engaged in (1) controversy about integrated aerometry and epidemiology research intended to correlate air pollution and health, (2) intra-agency debate about the government\'s responsibility for introducing catalytic converters for tailpipe emissions reduction and responding to the potential environmental and social consequences, and (3) inter-agency activities for the demonstration of scrubbers for smokestack emissions and further application of the control technology approach in energy-related environmental problems.
My principal conceptual contribution is "regulatory engineering." I define regulatory engineering as an approach to sociotechnical problems in which engineering practices are incorporated into regulatory and organizational changes, which in turn influences technical knowledge and identity formation. As EPA activities became closely associated with energy and economic issues toward the end of the 1970s, I argue that engineers took the initiative in demonstrating and evaluating control technologies for pollution abatement and energy development, scientists carefully studied environmental and health effects of these technologies, and regulators set up pollution standards and attainment deadlines accordingly. Studying the co-production of knowledge, institution, and identity through the lens of regulatory engineering helps us to understand technoscientific and managerial aspects of environmental governance beyond the 1970s EPA where technical feasibility considerations, economic incentives, and cooperative management expanded into legislation and regulation. / Ph. D.
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Ambient air pollution and low birthweight: a European cohort study (ESCAPE)Pedersen, M., Giorgis-Allemand, L., Bernard, C., Aguilera, I., Andersen, A.N., Ballester, F., Beelen, R.M.J., Chatzi, L., Cirach, M., Danileviciute, A., Dedele, A., van Eijsden, M., Estarlich, M., Fernandez-Somoano, A., Fernandez, M.F., Forastiere, F., Gehring, U., Gražulevičienė, R., Gruzieva, O., Heude, B., Hoek, G., de Hoogh, K., van den Hooven, E.H., Haberg, S.E., Jaddoe, V.W.V., Klumper, C., Korek, M., Kramer, U., Lerchundi, A., Lepeule, J., Nafstad, P., Nystad, W., Patelarou, E., Porta, D., Postma, D., Raaschou-Nielsen, O., Rudnai, P., Sunyer, J., Stephanou, E., Sorensen, M., Thiering, E., Tuffnell, D.J., Varro, M.J., Vrijkotte, T.G.M., Wijga, A., Wilhelm, M., Wright, J., Nieuwenhuijsen, M.J., Pershagen, G., Brunekreef, B., Kogevinas, M., Slama, R. January 2013 (has links)
No / Ambient air pollution has been associated with restricted fetal growth, which is linked with adverse respiratory health in childhood. We assessed the effect of maternal exposure to low concentrations of ambient air pollution on birthweight.
We pooled data from 14 population-based mother-child cohort studies in 12 European countries. Overall, the study population included 74-178 women who had singleton deliveries between Feb 11, 1994, and June 2, 2011, and for whom information about infant birthweight, gestational age, and sex was available. The primary outcome of interest was low birthweight at term (weight <2500 g at birth after 37 weeks of gestation). Mean concentrations of particulate matter with an aerodynamic diameter of less than 2·5 μm (PM2·5), less than 10 μm (PM10), and between 2·5 μm and 10 μm during pregnancy were estimated at maternal home addresses with temporally adjusted land-use regression models, as was PM2·5 absorbance and concentrations of nitrogen dioxide (NO2) and nitrogen oxides. We also investigated traffic density on the nearest road and total traffic load. We calculated pooled effect estimates with random-effects models.
A 5 μg/m3 increase in concentration of PM2·5 during pregnancy was associated with an increased risk of low birthweight at term (adjusted odds ratio [OR] 1·18, 95% CI 1·06-1·33). An increased risk was also recorded for pregnancy concentrations lower than the present European Union annual PM2·5 limit of 25 μg/m3 (OR for 5 μg/m3 increase in participants exposed to concentrations of less than 20 μg/m3 1·41, 95% CI 1·20-1·65). PM10 (OR for 10 μg/m3 increase 1·16, 95% CI 1·00-1·35), NO2 (OR for 10 μg/m3 increase 1·09, 1·00-1·19), and traffic density on nearest street (OR for increase of 5000 vehicles per day 1·06, 1·01-1·11) were also associated with increased risk of low birthweight at term. The population attributable risk estimated for a reduction in PM2·5 concentration to 10 μg/m3 during pregnancy corresponded to a decrease of 22% (95% CI 8-33%) in cases of low birthweight at term.
Exposure to ambient air pollutants and traffic during pregnancy is associated with restricted fetal growth. A substantial proportion of cases of low birthweight at term could be prevented in Europe if urban air pollution was reduced. / The European Union
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Urban air-pollution modeling at gray- zone resolutionsWeger, Michael 11 July 2024 (has links)
Die vorliegende Doktorarbeit beschäftigt sich mit der numerischen Ausbreitungssimulation von Luftschadstoffen im urbanen Raum. Als Strömungshindernisse prägen Gebäude maßgeblich das kleinskalige Windfeld und damit den horizontalen Transport und die Verteilung von urbanen Luftschadstoffen. Die häufig im Rahmen von Großwirbelsimulationen (engl.: Large Eddy Simulation, LES) zur expliziten Darstellung von Gebäuden verwendeten hohen räumlichen Auflösungen in Bereich von wenigen Metern erforden einen hohen Rechenaufwand und beschränken daher die Anwendung meist auf wenige Gebäudeblöcke.
Mittels eines neuen Diskretisierungsansatzes können Gebäude auch bei deutlich geringeren Auflösungen in Bereich der sogenannten urbanen Grauzone (horizontale Gitterweite > 10m) mittels diffuser Gebäudekanten explizit dargestellt werden. Im Rahmen dieser Arbeit wurde das urbane Dispersionsmodells CAIRDIO (v1.0) mit diesem neuen Diskretisierungsansatz entwickelt. Das Modell wurde zunächst mit einem Windkanalexperiment, welches die turbulente Ausbreitung eines Test-Tracers in einer Modellstadt beinhaltet, validiert. Dabei konnte bis zu einer horizontalen Auflösung von 40m noch eine hinreichend gute Übereinstimmung des Modells mit Konzentrationsmessungen erzielt werden, es wurde jedoch nur ein Bruchteil der Rechenzeit einer Referenzsimulation mit 5m Gitterweite benötigt. Der Ansatz mit diffusen Gebäuden erlaubt daher den Anwendungsbereich mikroskaliger Simulationen im Vergleich zu klassischen LES Simulationen erheblich zu erweitern, z.B. auf die Simulation ganzer Städte.
In einer ersten realistischen Fallstudie wurde das Modell CAIRDIO auf die Stadt Leipzig in Mitteldeutschland angewandt. Dabei wurde die Ausbreitung von realistischen Feinstaub und Ruß-Emissionen bei einer horizontalen Auflösung von 40m für das gesamte Stadtgebiet über einen Zeitraum von 2 Tagen (Anfang März 2020) berechnet und mit Messungen validiert. Es konnten die Auswirkungen der variablen Grenzschichtdynamik auf den urbanen Luftschadstofftransport mit dem Modell qualitativ korrekt wiedergegeben werden. Nur für verkehrsnahe Standorte führte eine höhere räumliche Auflösung von bis zu 5m noch zu einer besseren Übereinstimmung mit den Messungen. Insgesamt stellten jedoch bereits bei 40m Auflösung die Unsicherheiten in den Emissionen und den Randbedingungen den größten Anteil am Modellfehler dar.
In einer zweiten Fallstudie wurde eine weiter entwickelte Version des Modells CAIRDIO auf die Stadt Dresden im Elbtal angewandt. Der Fokus dieser Studie lag diesmal auf der den urbanen Raum umgebenden Orographie, welche erhebliche Auswirkungen auf die lokale Luftqualität bei Inversionswetterlagen haben kann. Dazu wurde das Dresdner Becken mittels geländefolgender Koordinaten zusammen mit den nach wie vor diffus repräsentierten Stadtgebäuden auf der Skala der urbanen Grauzone im Modell dargestellt. Neben der Dispersion von Ruß-Emissionen wurde auch die Ruß-Alterskonzentration, welche sich besonders gut zur Identifikation von orographisch bedingten Akkumulation von Luftschadstoffen eignet, über einen Zeitraum von insgesamt 24 Tagen modelliert. Die räumliche Verteilung der Alterskonzentrations-Hotspots wurde bei stabilen Wetterlagen neben den Gebäudeeffekten maßgeblich durch die Orographie beeinflusst, während bei neutraler Schichtung orographische Effekte nur gering ausgeprägt waren.
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Environmental risk factors and stroke pathophysiology : impact of particulate matter on vascular functionsEl Moghrabi, Yara 29 January 2024 (has links)
Titre de l'écran-titre (visionné le 11 janvier 2024) / Les accidents vasculaires cérébraux (AVC) constituent une cause majeure de décès et d'handicap des adultes au Canada. Les AVC ischémiques sont causés par l'interruption du débit sanguin cérébral par une thrombose ou embolie, et représentent 87 % des AVC. Les études épidémiologiques récentes ont souligné un rôle important, mais sous-estimé, des facteurs de risque environnemental dans les AVC ischémiques, notamment la pollution de l'air. L'exposition aux polluants atmosphériques, et en particulier aux particules fines (particulate matter; PM), corrèle avec une incidence élevée des AVC. Les données actuelles suggèrent que les PM induisent un stress oxydatif et conduisent au dysfonctionnement du système vasculaire et subséquemment à la progression des dommages cérébraux. Cependant, les mécanismes associés aux effets des PM sur la pathobiologie des AVC, restent peu étudiés. Après AVC ischémique, les fonctions de l'unité neurovasculaire qui intègre les interactions entre les cellules neuronales, gliales et vasculaires pour maintenir l'homéostasie cérébrale, sont dérégulées. Les études récentes suggèrent que les PM sont capables de traverser la barrière hémato-encéphalique (BHE) pour s'accumuler dans l'espace périvasculaire. Les péricytes sont des cellules périvasculaires multifonctionnelles qui jouent un rôle central dans la régulation des fonctions neurovasculaires. L'AVC induit le dysfonctionnement des péricytes, contribuant à la dérégulation de l'unité neurovasculaire. Les péricytes sont localisés dans l'espace périvasculaire ce qui les rend particulièrement exposés aux PM. Malgré cela, l'impact des PM sur les péricytes reste méconnu. Dans ce projet, nous avons étudié l'impact de l'exposition des péricytes aux PM in vitro, et avons évalué la réponse inflammatoire, la viabilité, le stress oxydatif et la mobilité des cellules. Nos résultats ont révélé que les PM activent la voie de signalisation stress-activated protein kinase (SAPK), impliquée dans la réponse des cellules exposées au stress. Nous avons démontré également que la viabilité des péricytes était fortement atténuée par les PM, surtout en conditions ischémiques. Ensuite, nous avons observé une altération de la voie endocytaire-lysosomale dans les péricytes exposés aux PM, ainsi qu'une dérégulation de leur capacité migratoire. Ces observations ont été associées à l'internalisation des PM par les péricytes. Nous avons établi que les cellules endothéliales cérébrales sont plus résistantes comparativement aux péricytes suite à l'exposition aux PM, et donc, l'impact des PM sur les fonctions vasculaires est médié essentiellement par le dysfonctionnement des péricytes. L'ensemble de nos résultats suggère que les PM induisent le dysfonctionnement des péricytes, entraînant ainsi la dérégulation des fonctions neurovasculaires et potentiellement la progression des dommages après AVC ischémique. / Stroke constitutes a major cause of death and handicap in adults in Canada. Ischemic stroke is caused by the interruption of the cerebral blood flow (CBF) by a thrombus or embolus, and represents 87% of all stroke cases. Epidemiological studies have highlighted an important, yet underestimated, role of environmental risk factors in ischemic stroke, notably air pollution. The exposure to atmospheric pollutants, and more particularly to particulate matter (PM), correlates with a high incidence of stroke. Recent findings suggest that PM induces oxidative stress and leads to the dysfunction of the vascular system, and subsequently to the progression of cerebral damage. However, the mechanisms associated with the effects of PM on the pathobiology of stroke, remain not fully studied. Following ischemic stroke, the functions of the neurovascular unit (NVU), which integrates the interactions among neuronal, glial, and vascular cells to maintain brain's homeostasis, are deregulated. Recent studies suggest that PM can cross the blood-brain barrier (BBB) to accumulate within the perivascular space. Pericytes are multifunctional perivascular cells that play an essential role in regulating neurovascular functions. Stroke induces the dysfunction of pericytes, leading to the deregulation of the NVU. Pericytes are localised in the perivascular space, which makes them particularly exposed to PM. Nevertheless, the impact of PM on pericytes remains elusive. In this project, we have studied the impact of the exposure of pericytes to PM in vitro, and have evaluated the inflammatory response, the viability, oxidative stress, and the mobility of cells. Our results have revealed that PM activates the stressactivated protein kinase (SAPK) signaling pathway, which is implicated in the responses of cells tostress stimuli. We have also demonstrated that the viability of pericytes was severely attenuated by PM, mainly under ischemic conditions. Next, we have observed alterations of the endocytic-lysosomal pathway in pericytes exposed to PM, as well as a deregulation of their migratory capacity. These observations were associated with the internalisation of PM in pericytes. We have as well established that brain endothelial cells are more resistant to PM exposure compared to pericytes, hence, the impact of PM on the vascular functions is mainly mediated by the dysfunction of pericytes. Our overall results suggest that PM induces the dysfunction of pericytes, leading to the deregulation of neurovascular functions, and potentially to the progression of damage following ischemic stroke.
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