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Impact of soil samples treatment and used measurement methods on heavy metals concentrations.
Kejík, Marek ; Marko, Michal (referee) ; Hajzler, Jan (advisor)
This bachelor thesis aims to explore the possibilities of treatment of soil samples and compare the suitability of selected analytical methods of analysis for determining the concentration of heavy metals. 7 reference certified materials of various soil types and one soil sample from the recreational area located in Brno were selected. Each soil sample was subjected to three different treatments. It is a method of melting into a solution, decomposition in aqua regia and aqueous extract. All thus treated samples were subsequently subjected to analytical methods for determining the concentration, specifically the ICP-OES and GF-AAS methods were used. To assess the suitability of selected methods of treatment of soil samples and analytical methods of determination, the 4 most risky elements were selected, namely arsenic, cadmium, copper and lead. The measured concentrations were compared with reference values of soil samples. Finally, the suitability of combinations of different sample preparation procedures and selected methods of analytical determination of the content of determined elements from soil samples was assessed.
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Validation of an innovative approach to the design of alkali-activated materials
Kejík, Marek ; Kucharczyková, Barbara (referee) ; Bílek, Vlastimil (advisor)
This thesis presents an approach to express the composition of alkali-activated materials based on three main characteristics. These are the type of activator, the molarity of the activator, and the volume fraction of the precursor or aggregate. The aim of this work is to provide a practical verification of this approach, in particular with respect to the amount of precursor, aggregates, and activator at a constant molarity of the three basic activator types (Na2CO3, NaOH, sodium water glass). The effects of these factors on their basic properties, namely workability, shrinkage, and mechanical properties, were studied for the prepared samples of pastes and mortars based on alkali-activated slag. These results were further supported by mercury intrusion porosimetry and electron microscopy. The results obtained confirmed the assumed key influence of the volumetric representation of the precursor, aggregates, and activator on the absolute values of the studied properties as well as on their relative changes. These were very different for the different activators, which is mainly due to the different abilities of the hydration products formed to fill the space between the slag and aggregate grains. The result of this work is a summary of the knowledge about the properties of alkali-activated materials over a given range of compositions, anchored by a universal approach for the design of the composition of these materials, which can be used in further research in this field.
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Impact of soil samples treatment and used measurement methods on heavy metals concentrations.
Kejík, Marek ; Marko, Michal (referee) ; Hajzler, Jan (advisor)
This bachelor thesis aims to explore the possibilities of treatment of soil samples and compare the suitability of selected analytical methods of analysis for determining the concentration of heavy metals. 7 reference certified materials of various soil types and one soil sample from the recreational area located in Brno were selected. Each soil sample was subjected to three different treatments. It is a method of melting into a solution, decomposition in aqua regia and aqueous extract. All thus treated samples were subsequently subjected to analytical methods for determining the concentration, specifically the ICP-OES and GF-AAS methods were used. To assess the suitability of selected methods of treatment of soil samples and analytical methods of determination, the 4 most risky elements were selected, namely arsenic, cadmium, copper and lead. The measured concentrations were compared with reference values of soil samples. Finally, the suitability of combinations of different sample preparation procedures and selected methods of analytical determination of the content of determined elements from soil samples was assessed.
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