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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
461

Radon als Tracer in der Luftqualitätsüberwachung

Westphal, Michael 25 February 2019 (has links)
Die Luftverschmutzung ist weltweit nach wie vor eines der größten Umweltprobleme. Bei der Ursachenanalyse gestaltet es sich als besonders schwierig den höchst variablen Einfluss der meteorologischen Bedingungen auf die Schadstoffkonzentration zu eliminieren (Immission) und damit wirksame Luftreinhaltemaßnahmen zu entwickeln. Mit der vorliegenden Arbeit werden Methoden vorgestellt und diskutiert, die das natürlich vorkommende radioaktive Edelgas Radon als atmosphärischen Tracer nutzen, um den Einfluss der meteorologischen Bedingungen auf die Immissionskonzentration auszuschalten und damit unterschiedliche Schadstoffkonzentrationen objektiv vergleichbar zu machen. Für einen Zeitraum von vier Jahren wurden hierfür an einer Luftgütemessstation des städtischen Hintergrunds die Luftschadstoffe Stickstoffdioxid (NO2) und Feinstaub als PM10 und PM2.5 sowie das radioaktive Edelgas Radon gemessen. Zudem wurden Daten einer verkehrsnahen Station verwendet sowie meteorologische Daten. / Air pollution is one of the main environmental problems worldwide. Beside the emission the spread of air pollutants is affected by the shape of the earth surface, the land use and the meteorological conditions of the near surface atmosphere. In this conection the meteorological conditions are very difficult to estimate, because these conditions are a result of the combination of many variables which furthermore change in a short period. With this work are methods presented and discussed which use the naturally occurring noble gas Radon as a tracer in the atmospheric boundary layer. Measured data were analyzed with statistical methods and the Radon-Tracer-Method. For a period of four years there were measured the air pollutants nitrogen dioxide (NO2) and particulate matter (PM10, PM2.5) and the tracer Radon. The measurement took place at an air quality control station in the urban background. Furthermore, there were used data from an urban traffic station at a high frequented main street (hot spot) and meteorological data.
462

Borne in Fire - A Study of Black Carbon Emitted from Coal Fired Power Plants in West Bengal, India.

Hendricks, Ra'eesah January 2023 (has links)
Black carbon has been reported to have major impacts on climate, environmental quality, and health. A chemothermal oxidation method, ordinarily used to isolate black carbon from soils, sediments and aquatic samples was applied to explore atmospheric samples. The results were then compared with thermal optical reflectance measurements, and then investigated in parallel with a health survey conducted during sampling. This study assesses atmospheric emissions from the NTPC Farakka coal-fired power plant in West Bengal, the distribution of emissions, the mobilization of black carbon, and its impact on pulmonary and cardiovascular conditions among respondents in Murshidabad and Malda, in West Bengal, India. Two measurement campaigns were conducted during winter and summer (November 2021 – June 2022); a total of 81 samples (Murshidabad) and 65 samples (Malda) were collected and analyzed and 193 respondents were surveyed for lung functionality. Over the study period, the mean concentration of PM2.5 and soot were observed to be 147 μg/m³; 113 μg/m³ and 1.52 μg/m³; 1.54 μg/m³ respectively. From the spirometry tests, it was concluded that there was chronic exposure to PM2.5 at both the sites, during the winter and monsoon campaigns. With increases in PM2.5 corresponding with higher numbers of restrictive and obstructive cases.
463

Particulate Matter Matters

Meyer, Holger J., Gruner, Hannes, Waizenegger, Tim, Woltmann, Lucas, Hartmann, Claudio, Lehner, Wolfgang, Esmailoghli, Mahdi, Redyuk, Sergey, Martinez, Ricardo, Abedjan, Ziawasch, Ziehn, Ariane, Rabl, Tilmann, Markl, Volker, Schmitz, Christian, Serai, Dhiren Devinder, Gava, Tatiane Escobar 15 June 2023 (has links)
For the second time, the Data Science Challenge took place as part of the 18th symposium “Database Systems for Business, Technology and Web” (BTW) of the Gesellschaft für Informatik (GI). The Challenge was organized by the University of Rostock and sponsored by IBM and SAP. This year, the integration, analysis and visualization around the topic of particulate matter pollution was the focus of the challenge. After a preselection round, the accepted participants had one month to adapt their developed approach to a substantiated problem, the real challenge. The final presentation took place at BTW 2019 in front of the prize jury and the attending audience. In this article, we give a brief overview of the schedule and the organization of the Data Science Challenge. In addition, the problem to be solved and its solution will be presented by the participants.
464

The Potential of Electrification in reducing Emissions from Passenger Cars in Stockholm County by 2030 : A Modeling Study of the Potential of Plug-In Hybrids and All-Electric Cars in reducing Greenhouse Gas Emissions and Air Pollution / Potentialen av elektrifiering att minska utsläppen från personbilar i Stockholms län till 2030 : En modelleringsstudie av potentialen av laddhybrider och elbilar att minska utsläppen av växthusgaser och luftföroreningar

Hedbäck, Arvid January 2021 (has links)
This study examines the potential of electrification in reducing greenhouse gas emissions and air pollution from passenger cars in a short- to mid-term time perspective. Using Stockholm County as a case study, this has been done in a three-step process by modeling the relative change in emissions between 2019 and 2030. Firstly, four scenarios have been created for 2030, each of which state the number of gasoline cars, diesel cars, PHEVs and EVs in use on a municipality-level. Secondly, for each scenario, the movement of traffic has been modeled on a car-by-car basis using the Scaper/MATSim transportation model at KTH. Thirdly, using emission factors from HBEFA, an emission model for 17 pollutants has been created for the modeling of hot emissions, cold start emissions, evaporation losses and non-exhaust emissions. Compared to 2019 emission levels, with EVs and PHEVs accounting for 64.5 % of the car fleet, the optimistic scenarios suggest that emissions of CO2, NMHC and NOx could decrease by up to 43.6, 63.5 and 84.7 %, respectively, by 2030. Besides electrification, for NMHC and NOx, these emission reductions are largely a result of technological improvements of combustion vehicles. Conversely, emissions of particulate matter (PM10 and PM2.5) are projected to increase by up to 45.6 % in the optimistic scenarios. Roughly corresponding to the increase in the total driving distance, this increase can be attributed to the lower cost of driving of electric cars and the projected population increase of 15.5 %.
465

Integration of Analysis and Deliberation to Evaluate Biodiesel Occupational and Environmental Exposures

Traviss, Nora M. 24 July 2008 (has links)
No description available.
466

[pt] CARACTERIZAÇÃO DA MATÉRIA ORGÂNICA PARTICULADA NA TRANSIÇÃO BAÍA DE GUANABARA OCEANO COSTEIRO USANDO MARCADORES ISOTÓPICOS E MOLECULARES / [en] CHARACTERIZATION OF PARTICULATE ORGANIC MATTER IN A GUANABARA BAYCOASTAL OCEAN TRANSITION USING ISOTOPIC AND MOLECULAR MARKERS

JULIANNA MARIA DE ALMEIDA MARTINS 17 July 2020 (has links)
[pt] A matéria orgânica particulada (MOP) em suspensão presente entre a Baía de Guanabara e o oceano costeiro foi caracterizada através de composição elementar (C e N), razões isotópicas (delta 13C e delta 15N) e marcadores moleculares (esteróis, n-álcoois e ácidos graxos) em dois períodos (verão e outono) ao longo de um transecto e de um fundeio de 25h. As assinaturas elementares (C/N = 5 a 23) e isotópicas (delta 13C = -27,7 a -16,2 por mil e delta 15N = 2,4 a 11,2 por mil) foram típicas de predomínio de matéria orgânica planctônica. Ácidos graxos (totais de 12,08 ± 7,78 Micrograma L–1 no verão e 22,06 ± 1,75 Micrograma L–1 no outono para o transecto; e de 13,47 ± 5,15 Micrograma L–1 no verão e 15,84 ± 3,61 Micrograma L–1 no outono para o fundeio de 25h) ocorreram como compostos de cadeia curta, mono- e poli-insaturados. Concentrações totais de esteróis variaram de 0,04 a 7,32 Micrograma L-1, com predominância de colesterol e fitoesteróis. n-álcoois foram um componente menos importante (0,01 a 5,67 Micrograma L-1). A abordagem multiparâmetros revelou a contribuição predominante de fontes autóctonas de MOP, o que reflete a influência da Baía de Guanabara sobre processos ecológicos na zona de transição aqui considerada. A contribuição fecal sobre a MOP também foi identificada, mas sendo um componente menos significativo, possivelmente pela diluição causada pelas fontes autóctonas ou pela degradação dos marcadores fecais. Além disso, a MOP de origem terrestre não é exportada da baía e, portanto, deve sofrer um processo de acúmulo nos sedimentos internos da baía. Isso suporta a necessidade de quantificar essa contribuição continental para melhor estabelecer o balanço de carbono na baía. / [en] Suspended particulate organic matter (POM) present between Guanabara Bay and the coastal ocean was characterized by elemental composition (C and N), isotopic ratios (delta13C and delta15N) and molecular markers (sterols, n-alcohols and fatty acids) in two periods (summer and fall) along a transect and a fixed station. Elemental (C/N of 5 to 23) and isotopic (delta13C= -27.7 to -16.2 per thousand and delta15N = 2.4 to 11.2 per thousand) signatures were typical for the predominance of planktonic organic matter. Fatty acids (totals of 12.08 ± 7.78 microgram L–1 in summer and 22.06 ± 1.75 microgram L–1 in the fall for the transect, and 13.47 ± 5.15 microgram L–1 in summer and 15.84 ± 3.61 microgram L–1 in the fall for the fixed station) were presente as short-chain, monoand poly-unsaturated compounds. Total sterol concentrations ranged from 0.04 to 7.32 microgram L–1, with the predominance of cholesterol and phytosterols. n-alcohols were a minor component (0.01 to 5.67 microgram L–1 ). The multi-proxy approach revealed an overwhelming contribution of autochthonous POM sources, reflecting the influence of the Guanabara Bay outflow on ecological processes in the transition zone considered herein. Fecal contribution to POM was also identified, albeit as a less significant component, possibly due to dilution caused by autochthonus sources or degradation of fecal markers. Moreover, the terrestriallyderived POM was not exported from the bay and, therefore, must experience an accumulation process in the inner bay sediments. This supports the need to quantify such continental contribution to better establish the carbon balance in the bay.
467

[en] AIR QUALITY ASSESSMENT IN RIO DE JANEIRO: FROM THE OLYMPIC GAMES TO THE PANDEMIC / [pt] AVALIAÇÃO DA QUALIDADE DO AR NO RIO DE JANEIRO: DAS OLIMPÍADAS À PANDEMIA

ELIZANNE PORTO DE SOUSA JUSTO 25 May 2022 (has links)
[pt] Este trabalho teve como finalidade o estudo dos níveis da composição química do MP2,5 e MP10 e gases coletados em áreas urbanas-costeiras, a fim de avaliar o impacto dos Jogos Olímpicos Rio 2016 e pandemia na qualidade do ar na Região Metropolitana do Rio de Janeiro. Os resultados mostraram o aumento de MP2,5 e MP10 devido às atividades urbanas desenvolvidas durante os Jogos Olímpicos e as obras que ainda estavam sendo realizadas no primeiro semestre de 2016. Em todas as estações as espécies inorgânicas refletiram a influência de aerossóis secundários e contribuições marinhas. As espécies Fe e Cu foram os elementos mais abundantes encontrados nas partículas, detectados principalmente em MP10. As fontes de emissão no MP10 foi obtido através do Positive Matrix Factorization (PMF); quatro fontes de aerossóis foram identificadas nos locais: veicular, spray marinho, formação secundária e um misto de ressuspensão do solo e industrial. Um total de 37 HPA foram determinados e a concentração média da soma dos 16 HPA considerados prioritários representou > 30 %. Para a maioria das estações, a distribuição foi caracterizada pela predominância de compostos com massa molecular entre 252 e 276. Em relação a pandemia, os resultados mostraram que o bloqueio parcial afetou os níveis de poluentes por meio da redução das emissões. Foram observadas a diminuição nos poluentes SO2, NO2 e CO; enquanto houve um aumento na concentração de O3. No geral, o bloqueio parcial contribuiu para a melhoria da qualidade do ar na cidade do Rio de Janeiro. / [en] This work aimed to study the levels of the chemical composition of PM2.5 and PM10 and gases collected in urban-coastal areas, in order to assess the impact of the Olympic Games and the pandemic on air quality in Rio de Janeiro. The results showed the increase of PM2.5 and PM10 due to urban activities developed during the Olympic Games and the works that were still being carried out in the first half of 2016. In all sites inorganic species reflected the influence of secondary aerosol and marine contributions. The vehicular emitted species Fe and Cu were the most abundant elements found in the particles, mostly detected in PM10. The source apportionment was obtained with Positive Matrix Factorization (PMF); four aerosol sources were identified at the sites: vehicular, marine spray, secondary formation and a mix of industrial and soil resuspension. A total of 37 PAHs were analyzed. The average concentration of the 16 PAHs sum considered priority represented > 30 %. For most stations, the distribution was characterized by the predominance of compounds with a mass between 252 and 276. Regarding the pandemic, the results showed that the partial lockdown affected pollutant levels by reducing sources emission. A decrease in SO2, NO2, and CO was observed; while there was an increase in O3 concentration. Thereby, the partial lockdown contributed to improving air quality in Rio de Janeiro City.
468

Design and implementation of a data acquisition system with filter quality evaluation / Design och implementering av ett datainsamlingssystem med filterkvalitet utvärdering

Karlsson, Örn Arnar January 2019 (has links)
Particulate matter is a growing health concern that is considered to contribute to many diseases. To develop appropriate air filtration systems, we need to understand how particulate matter affects air filters. In this project, we implement an automated data acquisition system for an air filter test rig. The data acquisition system allows us to gather empirical data on how particle matter affects air filters over time. Although the quality of the air filters does not reach critical levels, there is a measurable degradation. The collected data is used to train and validate a machine learning model that can evaluate air filter quality. This machine learning proved to be a powerful tool in air filter evaluation and performs with 99% accuracy on test data. The result of this project is a fully functioning data acquisition system along with a user interface that considerably reduces the number of man-hours needed to perform tests of filters. In addition, the automated data acquisition system can notify the operator when the rig needs a change of filter or when certain faults occur. Unfortunately, the project did not reach its original goal of being able to automatically determine when the test rig needs maintenance or re-calibration. / Luftburna partiklar är en växande hälsorisk som anses bidra till ohälsa. För att utveckla lämpliga luftfiltreringssystem måste en bättre förståelse nås för hur luftburna partiklar degraderar luftfilter. I det här projektet så implementeras ett automatiskt datainsamlingssystem i en testrigg för luftfilter. Datainsamlingssystemet samlar in empiriska data för hur luftburna partiklar degraderar filter över tid. Även om luftfiltren inte når kritiska nivåer, visar testerna på en mätbar degradering. Insamlat data används för att träna och validera en maskininlärningsmodell för att utvärdera filterkvalitet. Maskininlärning visade sig vara en kraftfull metod för att utvärdera luftfilter med 99% noggrannhet för testdata. Resultatet av det här projektet är ett fullt fungerande datainsamlingssystem tillsammans med ett användargränssnitt som avsevärt minskar tidsåtgången för att utföra test och utvärdera filter. Dessutom kan det automatiska datainsamlingssystemet meddela operatören när riggen behöver byta filter eller när vissa fel uppstår. Återstående arbete består i att implementera när testriggen behöver service eller kalibrering.
469

Evaluation of Indoor Aerosol and Bioaerosol Methods and a HEPA Intervention

Cox, Jennie D. 22 May 2018 (has links)
No description available.
470

Health impact of airborne particulate matter in Northern Lebanon : from a pilot epidemiological study to physico-chemical characterization and toxicological effects assessment / Impact sur la santé des particules atmosphériques au Nord Liban : enquête épidémiologique, caractérisation physico-chimique et étude des effets toxicologiques

Melki, Pamela 02 March 2017 (has links)
L'exposition à la pollution atmosphérique, notamment aux particules fines (PM₂.₅), représente un risque majeur pour la santé dans le monde entier, et d'autant plus dans les pays en développement.Le Nord du Liban est ainsi affecté par plusieurs sources de pollution d'origine anthropique, urbaine et industrielle. Pourtant, dans cette région, aucune étude ne s'est intéressée à l'impact des PM₂.₅ sur la santé publique. Il faut également souligner que les mécanismes de toxicité des PM₂.₅ ne sont pas totalement identifiés. Le but de ce travail est d'étudier la nature et l'impact sanitaire de la pollution atmosphérique particulaire dans le Nord du Liban. Nous avons procédé à une enquête épidémiologique, et prélevé des particules fines que nous avons caractérisées sur les plans physico-chimiques et toxicologiques. Deux régions ont été considérées dont une est située à proximité d'activités industrielles. L'étude épidémiologique et de perception menée dans les deux zones du Nord du Liban (310 questionnaires/zone traitée), a montré une relation entre gêne, maladies respiratoires et proximité des industries. Cette enquête a ainsi confirmé l'intérêt de mener une étude toxicologique dans cette région. Afin de renforcer les connaissances sur la toxicité pulmonaire des aérosols atmosphériques particulaires avec une attention toute particulière portée à l'étude de certains des mécanismes d'action suspectés d'être impliqués dans la cancérogénécité, les caractéristiques physico-chimiques et toxicologiques des particules fines (PM₂.₅₋₀.₃) prélevées sur les deux sites ont été étudiées. Les particules collectées ont montré une composition similaire sur les deux sites concernant les espèces majeures. La contribution des activités industrielles a été mise en évidence par des teneurs légèrement plus élevées de certains éléments traces, d'HAP et surtout par une teneur jusqu'à 100 fois plus élevée en dioxines. Nos résultats ont mis en évidence l'influence de nombreuses sources de combustion (diesel, essence, charbon et biomasse) ; la combustion de déchets et d'autres procédés industriels sont également suspectées. Un potentiel génotoxique et mutagène plus prononcé a été mis en évidence pour les particules collectées sur le site sous influence industrielle par rapport aux particules provenant du site sous influence rurale, à l'aide du test d'Ames en milieur liquide et le SOS chromotest. Les effets observés sont très probablement influencés par la fraction organique des particules. Afin d'approfondir la recherche des mécanismes génotoxiques des PM, des cellules bronchiques humaines (BEAS-2B) ont été exposées à différentes concentrations de particules. Les mécanismes de toxicité, tels que l'activation métabolique des HAP(CYP1A1) et les cassures double-brins (quantification de yH2AX par cytométrie de flux et in-cell western), ont été induits par les deux échantillons de PM₂.₅₋₀.₃ avec un effet plus prononcé pour les particules industrielles. Par ailleurs, les PM ont montré une tendance à perturber le fonctionnement du système de réparation de l'ADN (par l'expression des gènes OGG1, NTH1, APE1, NUDT1, DNMT1, MGMT, XPA et XRRC1, et l'expression des protéines PARP1, DNMT1 et OGG1). Les mécanismes de réparation des dommages de l'ADN ont ainsi été réprimés jusqu'à 48h d'exposition aux PM, notamment aux PM₂.₅₋₀.₃ collectées sous influence industrielle, et réactivés après 72h d'exposition. Ces dommages concernent les adduits encombrants à l'ADN, et ceux causés par le stress oxydant, des cassures des brins d'ADN et la méthylation. Nos résultats suggèrent des mécanismes d'action mutagènes, génotoxiques et épigénétiques impliqués dans la cancérogénécité des particules fines, en partie liés à la composition de la fraction organique. / Exposure to air pollution, especially fine particulate matter (PM₂.₅), remains a major health risk, mainly in the developing countries. Northern Lebanon is affected by several sources of anthropogenic, urban and industrial pollution. However, no studies have examined the impact of PM₂.₅ on public health in this region. In addition, it should be noted that the toxicity mechanisms of PM₂.₅ are not fully identified. The aim of this work is to study the composition and the health impact of the atmospheric particulates in Northern Lebanon. An epidemiological survey was performed and fine particles were extracted and characterized physico-chemically and toxicologically. This study was conducted in two sites, one of which is influenced by industrial activities. Perception and epidemiological survet, conducted in two areas in Northern Lebanon, rural and industrial (310 treatable questionnaires/area), showed a relationship between annoyance, respiratory diseases and living in proximity to industrial activities. Moreover, results confirmed the interest in conducting a toxicological study in this region. Hence, to contribute to fulfill the gap of knowledge about the pulmonary toxicity of particulate matter and the mechanisms of action involved in the carcinogenicity, the study of physicochemical characteristics and toxicological endpoints of PM₂.₅₋₀.₃ from both sites were performed. Physicochemical analyses of the collected particles evidenced similar characteristics in major species. In particular, we have shown slightly higher levels of PAHs and trace metals and up to 100 times higher dioxins concentrations at the vicinity of industries. Our results evidenced the influence of numerous combustion sources (diesel, gasoline, coal and biomass burning) ; waste combustion and other industrial processes are also suspected. A more pronounced genotoxic and mutagenic potential was evidenced after exposure to particles collected at the vicinity of industries when compared to the rural ones, using the Ames fluctuation test and SOS chromotest. The effects of the collected particles are probably related to their organic composition. In order to assess the underlying toxic mechanisms, human bronchial epithelial cells (BEAS-2B) were then exposed to different concentrations of the sampled PM₂.₅₋₀.₃. Genotoxicity mechanisms such as metabolic activation of organic compounds (CYP1A1) and consecutive DNA damages such as DNA strands breaks (yH2AX quantification by flow cytometry analysis and in-cell western assay) were induced by the two samples of PM₂.₅₋₀.₃ , with a more pronounced effect of industrial particles. Moreover, PM showed tendency to alter the DNA repair process (OGGI, NTH1, APE1, NUDT1, DNMT1, MGMT, XPA, XRRC1 gene expression and PARP1, DNMT1, OGG1 proteins expression). DNA repair mechanisms were repressed up to 48h of exposure to PM especially to the industrial influenced PM₂.₅₋₀.₃ and reactivated after 72h of exposure. The DNA damages involve bulky DNA adducts, oxidative stress damages, DNA strand breaks and methylation. These results suggest mutagenic, genotoxic and epigenetic mechanisms of action involved in the carcinogenicity of fine particles, partly related to their organic composition.

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