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Aerosolassoziierte Respiratorische NotfalleinsätzeBauer, Martin 15 March 2011 (has links) (PDF)
Luftverschmutzung ist ein zentrales Thema der Umweltmedizin. Dabei beeinflusst partikuläre Luftverschmutzung entscheidend die Luft, besonders auch in Leipzig. Die Problematik „Feinstaub“ steht aktuell im Fokus von Politik, Rechtssprechung, Presse und Wissenschaft. Zahlreiche Studien belegen die Zusammenhänge zwischen aerosolbelasteter Luft und vielgestaltigen Gesundheitsgefährdungen. Insbesondere das respiratorische System kann durch luftgetragene Partikel gravierende Schädigung erfahren.
Lange Zeit wurden ausschließlich die Massekonzentrationen der Partikel untersucht. Jüngere Forschungsbemühungen auf diesem Gebiet konzentrieren sich jedoch verstärkt auf chemische und physikalische Eigenschaften der Partikel.
Die vorliegende Arbeit untersucht die Einflüsse von Partikelkonzentrationen auf die respiratorische Gesundheit im prähospitalen Bereich der notfallmedizinischen Versorgung in Leipzig. Es galt hierbei vorrangig die Einflüsse von Anzahl, Oberfläche und Volumen der luftgetragenen Partikel auf die respiratorischen Notfallrisiken zu untersuchen.
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Emissions from realistic operation of residential wood pellets heating systemsWin, Kaung Myat January 2015 (has links)
Emissions from residential combustion appliances vary significantly depending on the firing behaviours and combustion conditions, in addition to combustion technologies and fuel quality. Although wood pellet combustion in residential heating boilers is efficient, the combustion conditions during start-up and stop phases are not optimal and produce significantly high emissions such as carbon monoxide and hydrocarbon from incomplete combustion. The emissions from the start-up and stop phases of the pellet boilers are not fully taken into account in test methods for ecolabels which primarily focus on emissions during operation on full load and part load. The objective of the thesis is to investigate the emission characteristics during realistic operation of residential wood pellet boilers in order to identify when the major part of the annual emissions occur. Emissions from four residential wood pellet boilers were measured and characterized for three operating phases (start-up, steady and stop). Emissions from realistic operation of combined solar and wood pellet heating systems was continuously measured to investigate the influence of start-up and stop phases on total annual emissions. Measured emission data from the pellet devices were used to build an emission model to predict the annual emission factors from the dynamic operation of the heating system using the simulation software TRNSYS. Start-up emissions are found to vary with ignition type, supply of air and fuel, and time to complete the phase. Stop emissions are influenced by fan operation characteristics and the cleaning routine. Start-up and stop phases under realistic operation conditions contribute 80 – 95% of annual carbon monoxide (CO) emission, 60 – 90% total hydrocarbon (TOC), 10 – 20% of nitrogen oxides (NO), and 30 – 40% particles emissions. Annual emission factors from realistic operation of tested residential heating system with a top fed wood pelt boiler can be between 190 and 400 mg/MJ for the CO emissions, between 60 and 95 mg/MJ for the NO, between 6 and 25 mg/MJ for the TOC, between 30 and 116 mg/MJ for the particulate matter and between 2x1013 and 4x1013 /MJ for the number of particles. If the boiler has the cleaning sequence with compressed air such as in boiler B2, annual CO emission factor can be up to 550 mg/MJ. Average CO, TOC and particles emissions under realistic annual condition were greater than the limits values of two eco labels. These results highlight the importance of start-up and stop phases in annual emission factors (especially CO and TOC). Since a large or dominating part of the annual emissions in real operation arise from the start-up and stop sequences, test methods required by the ecolabels should take these emissions into account. In this way it will encourage the boiler manufacturers to minimize annual emissions. The annual emissions of residential pellet heating system can be reduced by optimizing the number of start-ups of the pellet boiler. It is possible to reduce up to 85% of the number of start-ups by optimizing the system design and its controller such as switching of the boiler pump after it stops, using two temperature sensors for boiler ON/OFF control, optimizing of the positions of the connections to the storage tank, increasing the mixing valve temperature in the boiler circuit and decreasing the pump flow rate. For 85 % reduction of start-ups, 75 % of CO and TOC emission factors were reduced while 13% increase in NO and 15 % increase in particle emissions was observed.
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Spatial distribution of summertime particulate matter and its composition in Greece / Η χωρική κατανομή και σύνθεση των αιωρούμενων σωματιδίων στην Ελλάδα την περίοδο του καλοκαιριούΤσιφλικιώτου, Μαρία 05 February 2015 (has links)
A field campaign was conducted in Greece during the summer of 2012 (June 8 –
July 26) to investigate ambient particulate matter (PM) levels, chemical composition and
contribution of regional and local sources. Simultaneous collection of PM1, PM2.5 and
PM10 samples took place in seven different sampling sites in Greece. The sampling sites
included: i) one urban and one suburban station in Patras, ii) one suburban in
Thessaloniki, iii) one suburban and one background station in Athens, iv) one rural
background station at the Navarino Environmental Observatory (NEO) in southwest
Peloponnese and v) one remote background site at Finokalia in the northeast part of
Crete. These different sites were chosen in order to estimate the contributions of the local
emissions sources and long range transport. A suite of continuous/online instruments was
deployed in selected sites including an Aerodyne High Resolution Time of Flight Aerosol
Mass Spectrometer (HR-ToF AMS), an Aerosol Chemical Speciation Monitor (ACSM),
a Proton-Transfer Reaction Mass Spectrometer (PTR-MS), a PM2.5/PM10 Tapered
Element Oscillating Microbalance (TEOM), filter samplers (PM1, PM2.5 and PM10),
nephelometers, aethalometers and gas-phase monitors.
The campaign PM2.5 average ranged from 14 to 20 μg m-3 for the different sites.
The fine PM mass concentration and chemical measurements were quite similar in all
sites suggesting significant contributions of transported regional pollution and smaller
contributions of local sources. Sulfate and organics were major PM2.5 components in all
sites. Also nitrate, dust and sea-salt for the coastal areas were also important components
of the PM10 fraction. The sulfate levels were similar in all sites, while the concentration
of the organics and dust were more variable. Most of the organic aerosol was highly
oxygenated. Back trajectory analysis, based on FLEXPART, identified five source
regions (Greece, Athens, Turkey, Balkans, marine) each of which influenced the PM1
aerosol composition. / --
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In-Vitro Analysis of the Respiratory Toxicities of Fossil Fuel Combustion AshesOkeson, Carl D. January 2006 (has links)
Epidemiological studies have linked exposure to elevated levels of airborne particulate matter with increased incidences of several types of respiratory disease, hospital admissions and morbidity. Millions of tons of airborne particulate matter are generated and released into the atmosphere each year. However, particulate matter resulting from the combustion of fuel oil and coal are of particular concern, because they are generally composed of small particles that can easily penetrate deep into the lungs, and can contain significant concentrations of toxic transition metals, such as zinc, iron and vanadium. Pulmonary toxicity (i.e. damage caused to lung tissues) of particulate matter is currently evaluated via time-consuming in-vivo testing, or via in-vitro testing. Compared to in-vivo testing, in-vitro testing offers significant advantages in terms of time savings and sample throughput. Unfortunately, the number of in-vitro testing methods are currently very limited, and do not allow a thorough investigation of the mechanisms of particulate matter toxicity. In light of these issues, the goals of the study described here were three-fold: *To adapt several in-vitro toxicity assays currently used in other applications to use in measuring particulate matter toxicity on lung cell layers; *To use these adapted assays to quantify the toxicity of numerous types of oil and coal ashes with varying particle sizes and transition metal concentrations, and; *To use the same assays to quantify the toxicities of several transition metals found in coal and oil ashes to better understand their relative contributions to overall particulate matter toxicity. Three colorimetric in-vitro assays were chosen for adaptation, and proved effective in measuring adverse cellular response to particulate matter exposure. Particle size was shown to have a large effect on the overall cytotoxicity of particulate matter; fine (less than 2.5 μm aerodynamic diameter) particles proved substantially more toxic than coarse (larger than 2.5 μm aerodynamic diameter) particles. Dose-response experiments measuring the toxic effects of the transition metals zinc, vanadium and iron revealed that zinc was the most toxic; a concentration of 0.6 mM caused a 50% drop in cellular metabolism, compared to 3 mM and 4 mM for vanadium and iron respectively.
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Characteristics of Engine Emissions from Different Biodiesel BlendsWan, Curtis 04 January 2012 (has links)
Engine exhaust characteristics from two different biodiesel blends, formulated from soy and animal fat biodiesel blended with ultra-low sulphur diesel, were tested during two different test programs with similar operating conditions. Engine exhaust was measured in real-time for nitrogen oxides, total hydrocarbons, particle-bound polyaromatic hydrocarbons, and particle size distribution. Diesel particulate matter was collected on filters and subsequently analyzed for organic carbon, elemental carbon, soluble organic fraction, cations, and anions. The use of biodiesel was found to increase nitrogen oxide emissions, but decrease total hydrocarbons and particulate matter emissions. The most significant impact on emissions was the difference between the engine operating conditions rather than the fuel type. Minor differences were found between the soy and animal fat biodiesel blends through speciation of the diesel particulate matter.
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Characteristics of Engine Emissions from Different Biodiesel BlendsWan, Curtis 04 January 2012 (has links)
Engine exhaust characteristics from two different biodiesel blends, formulated from soy and animal fat biodiesel blended with ultra-low sulphur diesel, were tested during two different test programs with similar operating conditions. Engine exhaust was measured in real-time for nitrogen oxides, total hydrocarbons, particle-bound polyaromatic hydrocarbons, and particle size distribution. Diesel particulate matter was collected on filters and subsequently analyzed for organic carbon, elemental carbon, soluble organic fraction, cations, and anions. The use of biodiesel was found to increase nitrogen oxide emissions, but decrease total hydrocarbons and particulate matter emissions. The most significant impact on emissions was the difference between the engine operating conditions rather than the fuel type. Minor differences were found between the soy and animal fat biodiesel blends through speciation of the diesel particulate matter.
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Measurement of Ammonia, Methane and Particulate Matter Emissions from a Dairy BarnMali, Darius 04 September 2013 (has links)
The demand for meat and other animal products over the past couple decades has led to a changeover from small family operated farms, into large commercial facilities. The increase in animal density and population has created new issues related to waste management and pollution. Aerial pollutants, such as carbon dioxide, methane, ammonia, nitrous oxide and particulate matter, are all byproducts of agricultural processes. This study examines the concentrations, emission rates, and emission factors of ammonia, methane, and particulate matter that are emitted from a commercial dairy barn.
The commercial dairy facility was located near New Hamburg in Ontario, Canada. It has the capacity to house 501 animals total, split between lactating cows, dry cows, heifers, bulls and calves. Lactating cows are confined in tie stalls while the rest of the herd used free stall pens. The barn is mechanically ventilated and uses a set of 14 fans with diameters of 1.22 m to ventilate the barn.
Concentration data were measured over two sampling periods; the first took place in January – March 2013 and the second from May – July 2013. The pollutant concentrations, ventilation rates, and animal weights were used to generate emission factors based on an animal unit (AU – equivalent to 500 kg live mass) basis. The emission factors for ammonia, methane, PM10 and PM2.5 averaged over the two campaigns were 1.12 g hr-1 AU-1, 25.08 g hr-1 AU-1, 9.33 mg hr-1 AU-1 and 4.96 mg hr-1 AU-1, respectively and agree well with reported values in the literature.
The time of year had an impact on the emission levels as all of the pollutants, except methane, were higher in the second sampling campaign compared to the first. A large increase was seen in the ammonia and particulate matter, while a more moderate change
was seen in the methane. Peaks in ammonia emissions correlated well with feed times, and are highly influenced by animal activity. Methane emissions were dominated by the digestive process in the rumen, and have a lag period after feeding before the emissions spike. Although particulate matter increased, it was not correlated to a specific event in the barn. / Agriculture and Agri-Food Canada, Ontario Ministry of Agriculture Food, Ontario Ministry of Rural Affairs, Dairy Farmers of Canada, Dairy Farmers of Ontario
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Integration of Satellite Remote Sensing and Ground-based Measurement for Modelling the Spatiotemporal Distribution of Fine Particulate Matter at a Regional ScaleTian, JIE 18 November 2009 (has links)
Accurate information on the spatial-temporal distributions of air pollution at a regional scale is crucial for effective air quality control, as well as to impact studies on local climate and public health. The current practice of mapping air quality relies heavily on data from monitoring stations, which are often quite sparse and irregularly spaced. The research presented in this dissertation seeks to advance the methodologies involved in spatiotemporal analysis of air quality that integrates remotely-sensed data and in situ measurement. Aerosol optical depth (AOD) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) is analyzed to estimate fine particulate matter (PM2.5) concentrations as the target air pollutant.
The spatial-temporal distribution of columnar aerosol loading is investigated through mapping MODIS AOD in southern Ontario, Canada throughout 2004. Clear distribution patterns and strong seasonality are found for the study area. There is a detectable relationship between an AOD level and underlying land use structure and topography on the ground. MODIS AOD was correlated with the ground-level PM2.5 concentration (GL-[PM2.5]) at various wavelengths. The AOD-PM2.5 correlation is found to be sensitive to spatial-temporal scale changes. Further, a semi-empirical model has been developed for a more accurate prediction of GL-[PM2.5]. The model employs MODIS AOD data, assimilated meteorological fields, and ground-based meteorological measurements and is able to explain 65% of the variability in GL-[PM2.5]. To achieve a more accurate and informative spatiotemporal modelling of GL-[PM2.5], a method is proposed that integrates the model-predictions and in situ measurements in the framework of Bayesian Maximum Entropy (BME) analysis. A case study of southern Ontario demonstrates the procedures of the method and support for its advantages by comparison with conventional geostatistical approaches. The BME estimation, coupled with BME posterior variance, can be used to depict GL-[PM2.5] distribution in a stochastic context. The methodologies covered in this work are expected to be applicable to the modelling or analysis of other types of air pollutant concentrations. / Thesis (Ph.D, Geography) -- Queen's University, 2009-01-08 14:43:49.333
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A climatology of particulate pollution in ChristchurchAppelhans, Tim January 2010 (has links)
The research presented in this thesis provides a quantitative analysis of atmospheric influences on particulate matter pollution in Christchurch across a wide range of spatial and temporal scales. A complex interaction of low level flow characteristics that form in response to local and regional features of complex terrain, together with an urban setting that is characterised by low density housing, mostly comprised of single storey dwellings that are poorly insulated, regularly leads to nocturnal smog events during winter in Christchurch. Provided synoptic flow is weak, the above mentioned flow interaction promotes flow stagnation over the city, when nocturnal katabatic drainage flows and day-time north-easterly on-shore winds converge over the city. Additionally, undercutting of the density currents promotes highly stable atmospheric stratification close to the surface, so that, in combination, both horizontal and vertical air movement is suppressed. As particulate emission release from solid fuel burning for home heating coincides with this poor atmospheric dispersion potential, particle concentrations can increase substantially so that national air quality guidelines are regularly exceeded during winter in Christchurch.
At the core of this thesis is a classification based approach that examines the day-to-day probabilities of breaches of the national air quality guideline for PM over the last decade at a single location in Christchurch as a result of variations in meteorological conditions alone. It is shown that, based on variations in temperature and wind speed, up to 85% of exceedence occurrence can be explained. From this, concentration trends over time, when meteorological variability is kept to a minimum, are assessed and evidence is found that recent regulatory measures to enhance air quality are beginning to show positive effects. Atmospheric processes that control pollution dispersion on the mesoscale are investigated through means of atmospheric numerical modelling in a novel approach that assimilates observational climatic wind field averages to drive low level flow for two idealised case studies. It is shown that this approach is able to reproduce the observed diurnal concentration patterns very well and that much of these patterns can be attributed to mesoscale circulation characteristics and associated atmospheric dispersion potential, namely flow stagnation and recirculation of contaminants. When timing of stagnation and subsequent recirculation is such that it occurs within a few hours after peak emission release, concentration increase is enhanced and dilution is delayed, thus severely exacerbating the problem. Links between exceedence probabilities and synoptic situations that favour the degradation of air quality are established and various synoptic transition scenarios are examined with regard to local air quality. The progression of anticyclones across the country is identified to be the dominant synoptic control mechanism and it is shown that latitudinal variation in the progression path determines the extent of expected exceedence probability. On interdecadal hemispheric scales, it is found that a particular combination of local and synoptic atmospheric conditions that favours air quality degradation, shows a re-occurring pattern of frequency maxima (and minima) with a periodicity of approximately 14 - 16 years. For the synoptic part of this interdecadal variability, a close relationship to Southern Hemispheric pressure anomalies in high latitudes is revealed. Finally, for verification of the combined findings and to assess their prediction capability, a validation case study is given which shows that the applied methodology is able to capture day-to-day variations in pollution levels with acceptable (statistically significant) accuracy.
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Effects of particulate air pollution on cardiorespiratory admissions in Christchurch, NZ.McGowan, James Andrew January 2000 (has links)
Abstract Objective: In Christchurch there is concern that winter air pollution, dominated by particulate matter (PM₁₀) from domestic heating, causes a local increase in cases of cardiorespiratory disease. Our aim was to investigate whether the particulate levels did influence emergency hospital admissions, and if so to what extent. Method: Air pollution and meteorological data was obtained from a Canterbury Regional Council monitoring station. Two local hospitals provided data on emergency admissions for both adults and children with cardiac and respiratory disorders. All data was obtained for the period from June 1988 to December 1998. Missing PM₁₀ data was interpolated from other known pollution values when necessary. The PM₁₀ data was compared to the admissions data using a time series analysis approach, with weather variables controlled for using a generalised additive model. Results: There was a significant association between PM₁₀ levels and cardiorespiratory admissions. For children and adults combined there was a 3.4% increase in respiratory admissions for every interquartile (14.8 µg/m³) increase in PM₁₀. In adults there was a 1.3 % increase in cardiac admissions for each interquartile increase in PM₁₀. There was no relationship between PM₁₀ levels and appendicitis, the condition that we selected to be our control. Conclusion: In Christchurch there is a significant relationship between particulate levels and the admissions for cardiac and respiratory illnesses. The size of the effect is comparable to other international studies, and the greatest impact is seen on the respiratory system.
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