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Influence of titanium dioxide nanoparticles on soil properties
Zoufalá, Anna ; Řezáčová, Veronika (referee) ; Kučerík, Jiří (advisor)
This masters thesis deals with the influence of TiO2 nanoparticles on soil properties. Even though synthetic nanoparticles pose potential environmental risk, their impact on the environment is not researched enough. TiO2 nanoparticles are one of the most used and widespread nanoparticles and contamination of the environment with these nanoparticles is inevitable. One of the properties, thanks to which these nanoparticles are used, is the possibility of photocatalysis when the nanoparticles are illuminated with light in the UV wavelength. During this process, especially in the presence of water, highly reactive radicals are formed, which can oxidize organic compounds, which is mainly used for the degradation of organic pollutants. Therefore it is possible that in soil contaminated with TiO2 nanoparticles photocatalytic degradation of soil organic matter could occur. On the other hand, it is possible that polymerization reactions occur too. Thus the aim of this work is to clarify which processes occur after irradiating soil contaminated with TiO2 nanoparticles. To asses the impact of TiO2 nanoparticles and UV irradiation were caried out experiments during which soil contaminated with TiO2 nanoparticles was irradiated at different humidities. These samples were analyzed using thermogravimetry and FTIR spectrometry. No changes caused by TiO2 nanoparticles and UV light were detectable using thermogravimetry. Data acquired from FTIR spectrometry were processed using two different statistical methods – correlation analysis and principal components analysis. Correlation analysis was found not to be suitable method of data evaluation for the purpose of this work. Principal components analysis proved, that higher concentration of nanoparticles (5 wt. %) in combination with UV light does have impact on the composition of soil organic matter and its decomposition occurs mainly.
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Study of drugs intake by lettuce
Amrichová, Anna ; Zlámalová Gargošová, Helena (referee) ; Řezáčová, Veronika (advisor)
The aim of this thesis is to analyze the content of selected groups of drugs in cultivated lettuce. The theoretical part includes a chapter dedicated to the drugs used, their use, physicochemical properties, and their impact on the environment. Other chapters focused on analytical methods for determining drugs, hydroponic cultivation of lettuce, and some parameters of ecotoxicological tests. The experimental part began with the optimization of the QuEChERS extraction procedure. The optimized procedure was then applied to hydroponically grown samples of roots and leaves of lettuce containing selected groups of drugs, which were subsequently analyzed using liquid chromatography – mass spectrometry. The experimental part also addressed the ecotoxicological impact of different drug concentrations on hydroponically grown lettuce.
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Simultaneous determination of ultratrace concentration of nitric acid and nitrates in air using chemiluminescent online analysers
Čmelíková, Dorota ; Řezáčová, Veronika (referee) ; Alexa,, Lukáš (advisor)
The diploma thesis is focused on the development, optimization and real use of a continuous flow analyser for online determination of nitric acid and nitrates in air. The principle of analysis is photolytic conversion of nitrate in solution to peroxynitrite with subsequent detection by chemiluminescence reaction with luminol. The main aim of this thesis was to optimize parameters of analyser followed by practical use for analysis of urban air. The detection limit of gaseous nitric acid was 0,13 g·m3, resp. 0,10 g·m3 for nitrates in aerosol. The measured online concentrations were compared with reference offline analysis. The analysis of urban air was realized in two campaigns (September 2022 and February 2023) at Institute of Analytical Chemistry of CAS in Brno. The apparatus was placed in laboratory on the second floor and samples were collected from the window at Veveří street.
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Assessment of PHB effects at organismal and sub-organismal levels through E. fetida.
Demová, Kristína ; Řezáčová, Veronika (referee) ; Zlámalová Gargošová, Helena (advisor)
The use of biodegradable plastics, which are competitive with synthetic plastics and have the ability to be completely degraded by micro-organisms, is gaining ground. In real life conditions, biodegradation does not always proceed as expected, and these plastic particles may persist in the environment for long periods of time. Therefore, the verification of the safety of these plastics is the subject of many studies. This was also the aim of the present thesis, which deals with the impact of poly-3-hydroxybutyrate microparticles (representative of biodegradable plastics) on the organism Eisenia fetida (representative of soil organisms). Its effects were assessed using classical ecotoxicological tests. Methods to observe effects at the sub-organism level - using selected biomarkers - were also introduced and implemented. From the obtained results, no significant effect of the investigated biodegradable plastic on the test organism E. fetida was demonstrated, but the introduced methods can be used in the future to obtain more results to assess the effect at the sub-organismal level of the organism in a relevant way.
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Research on the content of risk elements in the material of PET bottles
Kryštofová, Petra ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This thesis deals with the research of the content of risk elements in the material of rPET (recycled polyethylene terephthalate), supplied from various countries, and the study of different factors (type of liquid, temperature) on the migration of antimony from this material. The recycling process has the potential to increase the content of unwanted substances and promote the formation of degradation products of chemical additives and by-products of polymerization, thus contributing to higher migration of these substances into food or food simulants [1]. The supplied rPET samples were subjected to total decomposition in an environment of concentrated sulfuric and nitric acid under the influence of microwave radiation prior to analysis. Prepared samples were analyzed by atomic absorption spectroscopy (AAS) techniques. The contents of Sb and Zn were determined by flame atomic absorption spectrometry (FAAS), and the concentrations of Pb, Cu, Zn, Cd, Cr, and Ni were determined by electrothermal atomic absorption spectrometry (ETAAS). Additionally, the concentrations of Sb were determined by this method in migration experiments. This thesis builds upon the author's bachelor's thesis, which included pilot experiments.
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Methodology to identify missing genetic resources in culture collections, strategy to fill the gaps
Komínek, Petr ; Komínková, Marcela ; Křížková, Iva ; Krejzar, Václav ; Aulický, Radek ; Kubátová, Alena ; Bár, Ladislav ; Kubizniaková, Petra ; Brožová, Jana ; Lebeda, Aleš ; Eichlerová, Ivana ; Malenovská, Hana ; Hanzalová, Alena ; Mertelík, Josef ; Kavková, Miloslava ; Mrázková, Marcela ; Kmoch, Martin ; Novotný, David ; Pánková, Iveta ; Skuhrovec, Jiří ; Petrželová, Irena ; Svoboda, Petr ; Reichelová, Markéta ; Urban, Marian ; Řezáčová, Veronika ; Valentová, Lucie ; Sedláček, Ivo ; Vendl, Tomáš ; Sedlářová, Michaela
The methodology was created under the National programme on conservation of microbial genetic resources of economical imortance. Its preparation was planned in the beginning of a current period of solving the National programme (2018-2022). The methodology describe procedures for the evaluation of specialization of individual collections from the point of view variability of genetic resources held on the collections. The goal of the methodology is to improve the work of microbial collections for the sustainable conservation of microbial genetic resources.
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Study of the content of risk elements in soils and plant material
Vlčková, Renáta ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the study of the content of selected heavy metals (Zn, Ni, Fe, Mn) in soils and mushrooms. The flame atomic absorption spectrometry method was used to determine the heavy metal content. Fungi and soil samples were collected at 18 sites in the Jeseníky region. The concentrations of heavy metals in the mushrooms were in the range from 140–582 mg/kg Zn, 48–380 mg/kg Fe, 5–19 mg/kg Mn and 3–8 mg/kg Ni. Zinc had the highest concentration value in all mushroom species. In soils, the concentrations of heavy metals ranged from 10–72 g/kg Fe, 52–1,000 mg/kg Mn, 29–115 mg/kg Zn and 6–50 mg/kg Ni. Iron was the most abundant element in the soils. Mushrooms contamination was assessed as a health risk in the study area. However, the pollution of forest soils was assessed as satisfactory and thus the productive function of the soil is not impaired. The type of forest cover was found to have minimal effect on the chemical composition of the soils.
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Risks associated with the use of biochar in the terrestrial ecosystem
Valeeva, Adeliia ; Řezáčová, Veronika (referee) ; Zlámalová Gargošová, Helena (advisor)
The aim of this bachelor thesis was to assess the ecotoxicity of biochar produced from sewage sludge in Ingolstadt. Biochar is one of the carbon storage options and it’s applied to the soil. Biochar has an effect not only on the terrestrial ecosystem in direct contact of organisms with the sample, but also on aquatic in the leaching of substances from biochar into water. Therefore, contact and aquatic tests were chosen to assess the ecotoxicological effect. The representative of the decomposers was the earthworm Eisenia fetida, the primary producer – the plant Lactuca Sativa and the Daphnia magna was chosen from the aquatic organisms. The test results differed slightly, but the lowest negative effect on the test organisms was shown by soil samples with the addition of 5 g/kg and 10 g/kg granular biochar.
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Study of surface water quality in the Ivančice area
Jonášová, Simona ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
Selected physical and chemical water quality parameters were measured at four sampling localities on the Jihlava River. Using UV-VIS spectrophotometry, inorganic forms of nitrogen, chlorides, total phosphorus and CODCr were determined. BOD5 was determined by the dilution method. Na+, K+ and Ca2+ ions, whose concentrations ranged from 5,75–108 mgl 1, were measured by flame emission photometry. Selected metals (Cu, Ni, Pb, Zn, Hg, Cr, Fe, Mn) were determined in water by the ET-AAS method. Decomposed sediments were determined by the FAAS method. Concentrations of Cr, Cu, Pb and Ni in water were in the range of 0,05–2,84 gl1. Metal concentrations in sediments ranged from 0,02–293 mgkg1, where nickel concentrations were above the limit. The occurrence of iron and manganese is due to the geological subsoil. For the other elements, anthropogenic source is assumed. From the measured data, the water quality is slightly variable in this locality and is classified as fourth or fifth class, i.e. as highly polluted water.
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Study of the influence of nanoparticles on water properties
Šram, Matěj ; Komendová, Renata (referee) ; Řezáčová, Veronika (advisor)
This work deals with the study of the influence of platinum nanoparticles with a size of 3 nm on the properties of water in a porous system. SiO2 with a defined pore size was used as a porous system, which can simulate the mineral component of the soil. The theoretical part deals with the properties of free and porous water and the impact of nanoparticles on the environment. In the experimental part, the properties of free water, water in the porous system and the influence of the presence of platinum nanoparticles on these systems are investigated using differential scanning calorimetry (DSC). The observed processes were melting, solidification and evaporation, and derived quantities such as crystallization and melting point.
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