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Pollen charakterisation in size segregated aerosol
Kolpakova, Anna ; Hovorka, Jan (advisor) ; Zíková, Naděžda (referee)
This bachelor thesis, in literature review, deals with bioaerosol issue, describes meaning of pollen, ways of pollen spreading and its influence on human health, summarize methods of pollen sampling from the air and common ways of pollen grains identification. In the experimental part, the use of the first stage of a High Volumetric Cascade Impactor (Hi-Vol) BGI-900 for bioaerosol sampling and subsequent SEM analysis was proved. Method of pollen separation from the impaction substrate, polyurethane foam, into homogeneous deposit on Nylon filter was optimized. Representative portion of the deposit was analyzed by SEM. There were taken 485 SEM pictures from 12 samples in 3 localities in the ČR. Pollen grains were identified in 295 SEM and determined into 9 genus and 4 families and grain deformities were quantified to be 24, 18, 50% for Prague, Brezno and Láz localities. Number of pollen increased with total aerosol mass in Prague locality only. Thre aleo identified insect secrction products borochomomes in the samples. Key words: pollen, pollen grain, bioaerosol, cascade impactor, SEM.
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Size segregated atmospheric aerosol in selected workspaces of coal strip mine
Basslerová, Barbora ; Hovorka, Jan (advisor) ; Svoboda, Petr (referee)
The workers are exposed to aerosol particles in a coal strip mine. These particles are usually generated by the Bucket-wheel excavators which break the mined rock. The goal of the thesis thesis was to compare the concentrations of atmospheric aerosol particles - PM on the Bucket-wheel excavator Schrs 1320, the Stacker ZPDH 6300 and the Bucket- wheel excavator K 800/N2 in the coal quarry Doly Nástup Tušimice, and then to answer the questions what is the main cause of increased concentration PMx and whether the mining machines are different from each other. The measurement was realized stepwise on every mining machine in the time period from 12. 8. to 2. 9. 2016. The concentrations of PM1, PM2,5 and PM10 were measured by two portable laser nephelometers in the cab drivers and the outdoor walkway of the mining machines with the integration time of 1 minute. The air temperature and the relative humidity were monitored in both types of settings in every five minutes. The PMx concentrations variability is usually determined by the type of work and by the type of smoking. Consequently, PM concentrations on the mining machines were compared at the morning exchanges and evening exchanges, during the outdoor cleaning by sweeping, the indoor cleaning by hoovering and during the smoking. The highest...
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Atmospheric aerosol vertical distribution in boudary layer
Dočekalová, Veronika ; Hovorka, Jan (advisor) ; Jančík, Petr (referee)
Particulate matter (PM) air pollution is one of the most important topics in the field of environmental protection, and coal strip mining is a significant source of coarse atmospheric aerosol. In order to implement appropriate regulations to improve air quality, we need to identify the major sources of pollution. PM is usually measured in a ground-based manner and its dispersion is only modelled. Therefore, the objective of this study was to measure concentrations of coarse aerosol in the atmospheric boundary layer above the area of the coal strip mine through experimental airborne measurements and to estimate pollution contribution of mining to the surroundings. Measurements were carried out from November 11 to November 26, 2012, at Vršany coal mine, Czech Republic. An electrically powered airship was used with a specially designed gondola carrying aerosol monitors DustTrak DRX and P-Trak. Temperature and relative humidity data were also recorded. Repeated flights were performed at several heights above mine edge level. PM1-10 and GPS data were recorded every second. Average airship velocity ranged from 6 to 7 ms-1 . Flight measurements were also compared to ground-based measurements of PM10 and meteorological data. Weather during our measurements was characterised by low temperatures, high relative...
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Urban street dust: mineralogy and shape analysis of aerosolized fraction
Lebedenko, Viktoriia ; Hovorka, Jan (advisor) ; Vodička, Petr (referee)
One important source of coarse particulate matter in urban atmosphere is the resuspended street dust. The aim of this study was to determine the emission potential of street dust samples, to conduct shape and mineralogical analysis of resuspendable fraction and on the bases of the findings carry out a comparison between the different sampling sites. The dust samples were collected in February 2014 in three cities: Ostrava, Prague and Pilsen. For the purpose of this study, nine samples from the selected sites were dispersed in a resuspension chamber. The samples were collected in the center of every city in the following locations: the main square, the tram railway and the curbside. Morphological and elemental analysis was performed using a Scanning Electron Microscope with EDS detector. The presence of mineral components such as quartz, chlorite, calcite, feldspar and kaolinite was observed. In samples from Ostrava were found spherical-shaped particles composed of iron oxides. The samples of Pilsen contained amphibole mineral fibers - actinolite. X-ray Powder Diffraction at high sensitivity showed the presence of amphibole asbestos in the samples from Ostrava and Prague. The mass of each size fraction of resuspended samples was determined. The mass size distribution was bimodal (2.5 µm and 8 µm),...
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A detailed study on aerosol particle size distribution in indoor and outdoor environments with attention to ammonium nitrate transormations
Talbot, Nicholas Philip ; Ždímal, Vladimír (advisor) ; Hovorka, Jan (referee) ; Vojtíšek, Michal (referee)
Due to its prevalence over large, densely populated areas, ammonium nitrate is an important chemical species in aerosol research. However, due to its volatility at ambient temperatures and over low temperature gradients, ammonium nitrate can be a difficult species to accurately measure. The volatility of ammonium nitrate is known to be dependent on temperature, relative humidity, the internal mixing state of the particle, and availability of the precursor gas constituents. The particle's physical state affects the equilibrium constant value of the ammonium nitrate - nitric acid / ammonia exchange and helps determine the dissociation rate. For indoor aerosol research, the outdoor originating aerosol particles' exposure to the new physical conditions indoors, such as changes in temperature, humidity, and particle-surface reactions within the microenvironment all accelerate ammonium nitrate dissociation. This increased rate of partitioning can generate artifacts on datasets, increase indoor particle formation, and accelerate the corrosion of cultural antiquities through acidification. The magnitude of these impacts is uncertain due to the current lack of knowledge on particle transformation processes when outdoor originating particles migrate indoors. To address this gap in knowledge, this thesis...
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The impact of building isolation on CO2 concentration in flats
Čejková, Eliška ; Hovorka, Jan (advisor) ; Holcátová, Ivana (referee)
1 ABSTRACT This diploma work investigates the influence of thermal insolation at residential buildings on the concentration of CO2 (carbon dioxide) in indoor environment. The studied area is a housing estate of panel buildings (flats) in Sezimovo Ústí city. The present work notices a positive impact of thermal insolation on energy demands of buildings and it is mainly saving consumed heat energy which is also connected with emission lowering of carbon dioxide emissions. The main problem which is soluted in the work is that total insolation is usually done without any ventilation solution. It means that it has later a negative impact on indoor environment/air quality in flats. The main part if this work presents measurements of indoor air quality - CO2 concentration, air change rate, temperature and relative humidity in an insolated (with plastic windows) and a non-insolated (with the original wooden windows) flats. The measurement lasted for three days in selected pairs of flats - with plastic and wooden windows. The measuremet took place in bedrooms because the behaviour of residents of households was very similar during their sleep. The air change rate was then caculated from CO2 concentration decay during period of 3 hours without residents. The main aim is to quantify these differences. The conclusion...
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Aerosol size distribution of PAH in urban atmosphere
Bendl, Jan ; Hovorka, Jan (advisor) ; Mikuška, Pavel (referee)
The aim of the study was to determine the 13 health risk PAHs (phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenzo(a,h)anthracene, benzo(g,h,i)perylene, ideno(1,2,3-cd)perylene and coronene; c-PAU highlighted) in the fractions of size-segregated aerosol of the urban air in Ostrava (2012, 2014) and Mlada Boleslav (2013) at low temperatures in winter, and to verify experimentally a sampling artifact, i.e., to quantify PAHs in the gas phase. For the particle size separation high-volume cascade impactor Hi-Vol BGI 900 was used. PAHs were determined by HPLC-FLD/PDA. In Ostrava in 2012 during the winter inversion (up to -25 řC), mean concentration of 13 PAHs in aerosol was 432 ng.m-3 ; in fraction 10 - 1 µm 119 ng.m-3 , 1 - 0,5 µm 185 ng.m-3 , 0,5 - 0,17 µm 91 ng.m-3 , in fraction < 0,17 µm 37 ng.m-3 and in the gaseous phase of min. 40 ng.m-3 . In the most unfavorable day 2. 2. 2012 (-18.6 ř C) reached the 24-hour average of 13 PAHs 890 ng.m-3 , the sum of carcinogenic PAHs 237 ng.m-3 and benzo(a)pyrene 32.3 ng.m-3 . An irregular and different decline of PAHs concentrations after inversion was measured: in fraction 1 - 10 µm 2.8 times, 0.5 - 1 µm 4.2 times, 0.5 - 0.17 µm 4 times and for <0.17 µm up to 7.6 times....
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Influence of local heating to PM10 levels in urban atmosphere
Píšová, Martina ; Hovorka, Jan (advisor) ; Škrabalová, Lenka (referee)
This master thesis evaluates the spatial variability of concentrations of PM10 on the area of towns Mladá Boleslav, Kosmonosy and small village Plazy during one month in the winter of 2013. Using a network measurements, we tried to determine whether sources of pollution are inside the city, or whether these harmful substances are transferred from the outside of the city to the area of the city. For the measurements we used a set of 9 portable laser nephelometers DustTrak (8520, TSI), which were placed on the roofs of schools. In the same time the device called beta-prachoměr (beta dust-meter) was continuously measuring concentrations of PM10, and we also monitored basic meteorological parameters (temperature, humidity, wind speed and direction). All these parameters were continuously measured at five minutes intervals. Also we did personal walks through the city, during which we measured personal exposure to PM10 concentrations. This exposure was compared with exposure of stationary monitors, and finally the differences were quantified. In Mladá Boleslav and in Kosmonosy, the same trend of concentrations of PM10 was observed at all selected locations in the city. Different trend of PM10 concentrations was observed in the village Plazy, where the peaks were higher and more frequent, especially in...
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Characteristic of aerosol particles in indoor environment of different types of libraries and archives
Mašková, Ludmila ; Smolík, Jiří (advisor) ; Hovorka, Jan (referee) ; Barták, Martin (referee)
Aerosol particles are one of the major pollutants in outdoor and indoor air. Particulate matter (PM) can be harmful for works of art by causing soiling and chemical damage, depending on particle size and chemical composition. This study includes indoor/outdoor monitoring of air quality in five archives in the CR, representing different outdoor environments: Zlatá Koruna (rural), Třeboň (small town), Teplice (industrial area), and two archives (National Library - NL and National Archives - NA) in Prague (large city with traffic). The NL and the archives in Zlatá Koruna, Třeboň and Teplice are only naturally ventilated, while NA in Prague is equipped with ventilation and filtration system. The measurements were performed during 4 intensive campaigns in different seasons of the year at every location. The measurements included particle number/mass concentrations, size distributions and chemical composition. Additional measurements were carried out in 2 museums, a depository, and a church. The aim of this study is to investigate concentrations, sources, and chemical composition of PM in the indoor environment, and to establish the relationship between the indoor and outdoor environment. The results showed that concentrations of fine particles in the indoor environment of the NA in Prague were...
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Source apportionment of atmospheric aerosol fraction using by highly time resolved characterisation
Pokorná, Petra ; Hovorka, Jan (advisor) ; Havránek, Vladimír (referee) ; Schwarz, Jaroslav (referee)
The effective air quality management in the heavy polluted areas has to be based on high-quality monitoring with properly designed monitoring network and targeted measurements, which provided information required to source apportionment. The thesis aim was to apportion sources of atmospheric aerosol based on highly time resolved data of mass concentration of size segregated aerosol, its temporal and spatial variability, elemental composition, OC/EC and size distribution of carcinogenic polyaromatic hydrocarbons. Sampling campaigns went during winter and summer in small settlement Březno by Chomutov, residential area Ostrava - Radvanice a Bartovice and Mladá Boleslav in the years 2008 - 2010, 2012, 2013. We determined mass concentrations of PM10, PM1-10, PM1.15-10 and PM0.15-1.5 and their size fraction ratios. Based on the size ratios, the source apportionment of fine fraction (PM0.15-1.15) with focus on PM0.34-1.15 is crucial. We examined seasonal and spatial variability of PM10, PM.2.5, PM1 and PM1-10. Based on the examination, we obtained representative highly-time resolved data with regards to season and sampling locality. We analysed dynamic of size distribution of particle-bond eight carcinogenic polycyclic hydrocarbons. Based on the results the source apportionment of PM0.34-1.15 is crucial....
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