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Spatio-temporal distribution of atmospheric aerosol in urban and rural environment
Bendl, Jan
Air quality in Europe remains a significant environmental concern, affecting the health and quality of life of its population. While stationary network ambient air quality monitoring allows for the observation of main trends, it is not fully representative of personal exposure of citizens due to high spatio-temporal variability of atmospheric aerosol. Therefore, highly time-and- space resolved measurements with state-of-the-art instruments and methods are needed to observe the aerosol variability, dynamics, identify hot-spots, and pollution sources, which are necessary for successful targeted mitigation measures. This thesis addresses this gap focusing on the characterization of spatio-temporal distribution of atmospheric aerosol in inhabited environments. Novel mobile measurement systems were developed and employed to investigate diverse environments, including rural, urban and suburban area. Aerosol source-apportionment were conducted, and the toxicological effects associated with these environments were also investigated. A novel mobile measurement system was developed for personal exposure measurements and pollution mapping in urban and rural environments. The system was used to measure air quality in the Munich subway, revealing high aerosol dynamics with significantly higher concentrations of...
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Analysis of organic compounds in the soil-biochar-salad system
Hlaváčová, Josefína ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
The bachelor’s thesis presented focuses on the analysis of polycyclic aromatic hydrocarbons extracted from lettuce, soil, biochar and soil mixed with biochar. Polycyclic aromatic hydrocarbons are introduced into the biochar during the production process, i.e., pyrolysis. After applying the biochar to the soil, the polycyclic aromatic hydrocarbons can be released into the soil and contaminate it. The theoretical part of the thesis focuses on the production and characterisation of biochar, its applications to the soil and subsequent changes it induces within the soil. The experimental part focuses on the optimization of the microwave-assisted extraction process. Furthermore, experiments were carried out, assessing the influence of the added biochar on the concentration of polycyclic aromatic hydrocarbons within soil and lettuce. The sample analysis included microwave-assisted extraction and quantitative and qualitative determination using GC/MS/MS. The samples analysed were assessed for the presence and concentration of 16 different polycyclic aromatic hydrocarbons, prioritised by the U.S. Environmental Protection Agency. The analysis of the samples of lettuce grown in the soil containing biochar display a higher concentration of polycyclic aromatic hydrocarbons compared to samples without biochar. The analysis of the lettuce roots showed identical results.
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Determination of content of organic compounds in biochar
Novotná, Martina ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
Biochar is created during the pyrolysis of organic biomass. Once added into the soil, it can improve its features. Biochars made from sewage sludge have various compositions. It is because of the vast difference between entrance materials. Organic pollutants can be absorbed into its surface during the cooling proces sof pyrolysis. If released into the enviroment, these compounds can cause inhibition of plant growth, get into food chains and adversely affect living organisms. Organic pollutans are determined most often by GC/MS after organic solvent extraction.
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Needles as bioindicators for assessing contamination levels of PAHs
Mikulíková, Iva ; Zlámalová Gargošová, Helena (referee) ; Vávrová, Milada (advisor)
Bioindicators are used to monitor the level of the environmental pollution. Plant bioindicators are most frequently used, particularly mosses, lichens and conifers. This thesis focuses of the monitoring of polycyclic aromatic hydrocarbons alkyl-derivates concentration in the needles, that were taken in different locations in the Czech Republic. Analytes were extracted by mixture of n-hexane and dichlormethane. The acquired extract was cleaned up by column chromatography with activated silicagel and florisil. Gas chromatography - mass spectrometry was used for final analysis.
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Determination of organic substances in tar formed after biomass combustion and gasification
Hájek, Radek ; Mravcová, Ludmila (referee) ; Vávrová, Milada (advisor)
Biomass pyrolysis and gasification techniques count among basic technological procedures for its use as a source of energy. As a side-effect, production of tar can be considered. Tar is a complex mixture of various organic compounds and affects negatively both the environment and the facilities where biomass is processed. Within the scope of this master thesis the analysis of tar samples from different materials was performed. As an appropriate analytical method the gas chromatography combined with flame ionization detection (GC-FID) and time-of-flight mass spectrometry (GC-TOF-MS) was chosen. The concentrations of volatile organic compounds known as BTEX, polycyclic aromatic hydrocarbons (PAH) and phenolic compounds were assessed.
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Substituted polyaromatic compounds in environmental components
Kubalík, David ; Mravcová, Ludmila (referee) ; Vávrová, Milada (advisor)
This work is focused on substituted polycyclic aromatic hydrocarbons (PAHs) in environmental compartments. The thesis examined the development of these compounds and their entry into the ecosystem. Due to their proven negative characteristics to be addressed also their toxicology. The next section discusses the appropriate methods, including sampling, sample preparation and final determination. The conclusion of this work forms draft standard operating procedure for their determination.
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Analysis of organic substances present in biochar
Bača, Ondřej ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
This master's thesis deals with the analysis of organic substances, which are present in biochar. Biochar contains a number of organic compounds, that can be toxic and also carcinogenic to living organisms. In order for biochar to be used to improve soil quality or to be used for other applications, its safety must be declared by European or international certifications. Relevant European and international standards have been created for the determination of organic substances, that could be present in biochar. The theoretical part of the thesis was focused on selected organic substances, the process of pyrolysis and thermochemolysis, biochar characterisation and the used analytical methods. The experimental part of the thesis consisted of extraction with toluene and after that the determination of concentration of the 38 polycyclic aromatic hydrocarbons was performed. Qualitative analysis was performed by two-dimensional gas chromatography. Biochar samples were also subjected to thermochemolysis method and then they were analysed on GC-MS again. In both analytical methods, a large number of substances from groups such as PAHs, carboxylic acids, amines, substituted naphthalenes etc. was found, as well as smaller number of eg. polychlorinated biphenyls.
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Detailed characterization of pyrolysis oil by separation techniques and mass spectrometry
Žvaková, Veronika ; Mravcová, Ludmila (referee) ; Čáslavský, Josef (advisor)
The aim of this work is detailed characterization of pyrolysis oil by advanced analytical separation methods and mass spectrometry. During the pyrolysis process decomposition of complex organic material take place in the presence of high temperatures and the absence of oxygen. Condensable part of vapours and aerosols forms viscous liquid called pyrolysis oil which is a complex mixture of large amount of compounds. In this work samples from microwave pyrolysis of woodchips and sewage sludge from wastewater treatment plant Brno-Modřice were analysed. Samples were provided by Bionic Laboratories company. Samples were separated by column chromatography on activated silica. For detailed characterization of each fraction gas chromatography with mass spectrometry detection and comprehensive two-dimensional gas chromatography with mass spectrometric detection with time of flight analyser were used. Substances that have been identified can be divided into several groups: alkanes, alkenes, aromatic hydrocarbons, polycyclic aromatic hydrocarbons, alcohols, aldehydes, esters, carboxylic acid and heterocycles.
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Analysis of tar formed by combustion of biomass
Chytil, Václav ; Čáslavský, Josef (referee) ; Vávrová, Milada (advisor)
This bachelor's thesis is focused on the analysis of the tar formed during combustion of biomass. Samples of the tar were provided by Energy Institute, Faculty of Mechanical Engineering, Brno University of Technology. BTEX, polycyclic aromatic hydrocarbons (PAHs) and n-alkanes were chosen as groups of target compounds. Samples (tar solutions in acetone) were refined before the final analysis. In the case of BTEX and n-alkanes, only filtration and dilution were used. In the case of polycyclic aromatic hydrocarbons, samples were filtered and then cleaned-up by column chromatography using silica gel. Gas chromatography with flame ionization detector (GC-FID) was chosen as an appropriate analytical method for the determination of target compounds from selected groups of BTEX and n-alkanes. Target compounds from the group of polycyclic aromatic hydrocarbons were determined by gas chromatography with mass spectrometric detection (GC-MS).
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