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Approaches to quantification of occult deposition of sulphur and nitrogen from fog and rime
Šrédlová, Kamila ; Hůnová, Iva (advisor) ; Hovorka, Jan (referee)
The aim of this bachelor thesis is to summarize available approaches for quantification of occult deposition of sulphur and nitrogen from fog and rime. Atmospheric deposition is a complex of processes by which pollutants are transferred from the air to the earth's surface and therefore it contributes to the atmosphere's self-cleaning. At the same time it represents an input of these pollutants to other components of the environment. Atmospheric deposition consists of dry deposition, which occurs in the absence of precipitation, and wet deposition, which occurs during precipitation. Wet deposition further consists of a vertical component (rain, snow, hail) and an occult component (fog, rime, hoarfrost). The common approach to quantifying total deposition nowadays is simply combining dry plus vertical wet deposition. But when applying this approach and neglecting occult deposition we are likely to substantially underestimate the true total deposition (e.g. Hůnová et al., 2011). This means we don't know the actual amount of pollutants transferred to the environment. The importance of occult deposition rises with increasing altitude (Lange et al., 2003). Occult precipitation also often contains higher concentrations of ions and stays longer in contact with the vegetation than vertical precipitation. There are...
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Droplet size evolution during rain event
Kim, Yong Min ; Hovorka, Jan (advisor) ; Braniš, Martin (referee)
This work will focus on measuring the rain drop size distribution during several episodes of precipitation. From the data matrix a simplified graph - color contour maps were drawn. The dynamics of the size of rain drops during a rain will be linked to the type of precipitation and global movement of air masses from withholding episode.
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Aerosol in indoor microenviroment of homes
Pařík, Radim ; Braniš, Martin (advisor) ; Hovorka, Jan (referee)
This literature review is composed of resources from Web of Science. The study deals with problematics of the indoor air pollution of homes. It is focused on the aerosol, especially PM2,5 particles, which present the biggest danger for human health. This work points out the analysis of indoor and outdoor emission sources, distribution of particles, levels of pollution in the different geografical, social and cultural regions and health effects of these particles. Key words: aerosol, homes, indoor environment, air quality, fine particles
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The effect of size, location and occupancy on air quality of classrooms
Stupková, Kateřina ; Braniš, Martin (advisor) ; Hovorka, Jan (referee)
This thesis is focused on investigation of size differentiated mass concentrations of aerosol in relation with size, location and occupancy of classrooms. The motivation to write this thesis was research of aerosol effects on human health. People in developed countries spend most of their time indoors thus indoor air quality affects their performance, well-being and health. The aerosol particles could be toxic, allergenic and carcinogenic. Higher concentration of particulate matter (PM) could affect performance and well-being of students during lessons. The aims of the study were examination of outdoor/indoor relation of PM according to classrooms locations and occupancy effect on the PM concentrations. Microclimatic and meteorological factors (e.g. temperature, humidity) were also assessed. Measurements were performed simultaneously in three size different classrooms in a building of Charles University in Prague (Benátská 2) and outside the building. The measurements were undertaken during one year, when each campaign contained 3 or 4 days of a month. The occupancy and changes in natural ventilation were monitored in each classroom during every campaign. Cascade impactors Sioutas were used for 24-hours PM collecting. The concentrations were determined gravimetrically. Concentrations of fine...
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Assessment of odour annoyance in Štětí
Mikšovská, Petra ; Hůnová, Iva (advisor) ; Hovorka, Jan (referee)
This thesis solves the odour issue in the ambient air. Due to the rising of a standard of living, people are no longer tolerant to excessive odours in the environment. Subject of the research is a perception of odour by inhabitants of the town Štětí. Štětí belongs to areas facing odour annoyance of its inhabitants, where the main source is a paper mill Mondi Štětí a.s. The goal of this thesis is to find out if the inhabitants of the town percieve the odour annoyance coming from the paper mill as problematic and explore their opinion of the odour situation in the area with respect to a near past, wish to the future and frequency of annoyance. Next goal is to find out if there exist a relation between immission concentrations of odours typical for a paper mill industry (sulfane, TRS) and subjective assessment of odour intensity by enquired inhabitants, and also what effect have different factors affecting odour perception (age, sex, pregnancy, smoking, personal and family relationship to the paper mill and adaptation to odours) on this relation. Method chosen to get the answers is a repetitive questioning of the inhabitants. In years 2010-2011 there were 16 events on which were made personal interviews with the inhabitants of Štětí near the immission measuring stations in Štětí. Totally 538 people...
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Surface ozone influence on native vegetation: results based on ozone visible symptoms and stomatal flux
Matoušková, Leona ; Hůnová, Iva (advisor) ; Albrechtová, Jana (referee) ; Hovorka, Jan (referee)
Regarding the vegetation, the most affected areas by high levels of surface ozone (O3) are the mountain ridges. Our study has been carried out in the Jizerske hory Mts. High O3 levels together with the convenient environmental conditions for stomatal conductance could be a threat for the health of recovering ecosystems in this area. The aims of this study was both to assess the influence of O3 on vegetation in the Czech mountains and to provide recommendations and outlooks for possible future using of relatively new methods (visible symptoms and stomatal O3 flux modelling) used for O3 impact assessment on native vegetation in the field; that means physiologically relevant methods for the determination of O3 influence. During 2006 and 2007, O3-like visible symptoms were assessed on the leaves of seven species at four sites. Symptoms on only two species (Fagus sylvatica L. and Rubus idaeus L.) have been determined as O3-induced. To our knowledge, it is the first study in the Czech Republic in which the O3-like symptoms on native plants have been verified by the Ozone Validation Centre for Central Europe. Our results based on O3-induced symptoms indicate that ambient O3 is likely to have a much lower impact than expected, considering the measured O3 concentrations (measured with passive samplers) and...
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Environmental tobacco smoke in bars and restaurants
Tesař, Tomáš ; Braniš, Martin (advisor) ; Hovorka, Jan (referee)
Tobacco smoking has been proved to be harmful to human health and is a known cause of many diseases. It has been shown that not only active smoking can cause health inconveniences - even an exposure to the environmental tobacco smoke (so called secondhand - SHS - or passive smoking) is a serious threat to human health, in some aspects nearly as severe as active smoking. Being aware of these risks, many countries have recently amended their policies which more or less restrict smoking in public places, especially workplaces and hospitality venues. In the Czech Republic, the smoke-free policy belongs to the less strict related to other countries, because it does not restrict smoking at all public places - restaurant and bar owners can choose whether their venue is smoke-free or not and their duty is only to label their venue both outside and inside. The law also enables the option of setting smoking and non-smoking spaces within the restaurant or bar. In a representative sample (over 100) of smoking and non-smoking sections of these restaurants and bars the concentrations of PM2.5, a marker of SHS concentrations, were measured with a photometer. The venues were divided into 3 groups according to the extent of separation of the sections. Parallel to the measurements, the gender composition and smoking...
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Concentrations of indoor submicrometer and supermicrometer particulate matter in a primary school in Prague
Štolcpartová, Jitka ; Braniš, Martin (advisor) ; Hovorka, Jan (referee)
Children are a susceptible group to environment pollution. The environment, in which they spend the most time, is the home, the second is the school. Therefore, the indoor environment of a school affects their health, wellbeing and even school results. The present work investigated concentrations of air pollutant, aerosol particles, in the specialized classrooms (computer lab, arts and biology/chemistry) in an elementary school, Prague. Direct reading instruments measuring mass concentration of four aerosol fractions and number concentration of submicrometer particles were used for measurement. Measurements were carried out for four weekdays in each month from November 2011 to July 2012. It was found that mass concentrations of submicrometer particles were dependent on outdoor concentrations, in contrast to supermicrometer particles which were affected mainly by physical activities of students and outdoor concentration had a minimal effect. Increased number concentrations of submicrometer particles were observed only during children presence, concentrations were probably induced by student activities during lessons. Seasons also influenced mass concentrations, when the highest indoor and outdoor concentrations were recorded in a spring/autumn season. Classroom location affected submicrometer...
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PAH bond to nanoparticles of atmospheric aerosol: substrate specifity.
Bendl, Jan ; Hovorka, Jan (advisor) ; Cajthaml, Tomáš (referee)
Polycyclic aromatic hydrocarbons (PAHs) are reviewed including their chemical and chemical- physical features, their impact on health and the environment. Different behaviour of PAHs is mentioned. The detailed instruction for the measurement using high-volume cascade impactor BGI 900 (Hi-Vol) is described. Cleaning, equilibration, weighting, protection against contamination of the substrates and technique of the measurement were introduced. The experiment was done: under the last teflon back-up filter the extra PUF substrate was placed, where after the air exposition the significant amounts of gaseous phase of phenanthrene, anthracene, fluoranthene, pyrene and benzo(a)anthracene were captured. The extent of the volatile PAHs capture correlated positively with the vapour pressure (ranging from 10-4 to 10-1 Pa.). The other measured PAHs (coronene, benzo(ghi)perylene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenzo(a,h)anthracene and indeno(1,2,3-cd)pyrene) with vapour pressure from 10-5 to 10-10 Pa were not captured. The experiment found out that polyurethane (PUF) substrates captured in noticeable amount the volatile phase of PAHs and therefore the correction for the capture of gaseous phase in the particle size fractions of PAHs was calculated. The deduction for the...
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