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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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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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Study of the influence of polyethylene terephthalate recycling on the quality of the resulting recyclate
Mach, Jakub ; Řezáčová, Veronika (referee) ; Kučerík, Jiří (advisor)
Plastics and recycling of plastics is a frequently discussed topic. The output of sythetic polymers is rising exponentially every year. In accordance with the sustainable development, development of effective recycling techniques enabling to process these huge amounts of waste and convert it back into useful material is essential. The aim of this work was to study qualitative effects of production methods, various types of recycling processes and degree of degradation of polyenthylene terephtalate on results of differential scanning calorimetry (DSC) analysis. In experimental part, analyzes of 62 regranulates of recycled PET were performed. The samples from various manufacturers differed (manufacturers use different technologies) in terms of mechanical and physico-chemical properties or additives. The results confirmed that the properties of recycled PET have an impact on thermophysical properties recorded using DSC. A simple DSC run enables distinguishing a number of fundamental qualitative properties of PET, in particular crystallinity, melting point and enthalpy, temperature and enthalpy of crystallization and glass transition temperature and in this work we show that their mutual relationship enables to estimate the quality of recycled material and the possibilities of its further use.
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Analysis of pesticides in the environment using the QuEChERS method
Vašinková, Alena ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
This thesis focuses on pesticides in the environment, more specifically in cereals. Pesticides were monitored in various samples of cereals (barley, rye, oats, and wheat) within the thesis. The monitored substances were isolated in selected samples and concentrated using the QUECHERS method. Gas and liquid chromatography were used to determine pesticides. The theoretical part consists of the common types of pesticides, divided by the ease with which these substances into food and their impact on humans and environment. It also mentions current health protection legislation and environmental legislation.
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Analysis of fluoroquinolone antibiotics in the soil
Vdolečková, Monika ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
The thesis dealt with the global problem of the occurrence of pharmaceuticals in the environment, specifically fluoroquinol antibiotics (ciprofloxacin and enrofloxacin), which are among other critically important antibiotics. These drugs enter the soil environment through the application of already contaminated animal waste (e.g. manure) or through wastewater used in irrigation or through the application of treated sewage sludge, which may contain drug residues. Increasing concentrations of these antimicrobial drugs in the environment provide an environment for the emergence and spread of microbial resistance. The accumulation of these drugs then leads to the emergence of resistance to these antibiotics. The experimental part of the thesis focused on the optimization of a method for the extraction and subsequent determination of fluoroquinolones in soil and litter. For this purpose, parameters related to the extraction yield of fluoroquinolones from the soil matrix were optimized, such as sample weighting, selection of a suitable extraction medium, SPE performance, elution method from the SPE, etc. Extraction recoveries of 70 to 140 % were achieved as part of the optimization. Finally, the optimised method for extraction of fluoroquinolones from poultry litter and soil samples provided by the ÚKZÚZ was used. The experimental results confirm the long-term persistence of these drugs in the environment.
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Application of a novel continuous sampler for the determination of compounds in ultrafine aerosol
Hlaváčková, Hana ; Řezáčová, Veronika (referee) ; Alexa,, Lukáš (advisor)
The diploma thesis is focused on the use of new type of continuous sampler for the determination of compounds in ultra-fine aerosol. The aim of the study was to optimize parameters of the aerosol sampler CGU-ACTJU (Condensation-Growth Unit – Aerosol Counterflow Two-Jets Unit) and its application for the real aerosol samples. The ACTJU sampler connected to upstreamed CGU enables sampling of ultra-fine fraction of particulate matter to the diameter about few nanometers. The measured results from CGU-ACTJU were compared with commercial sampler (cascade impactor) with subsequent offline analysis. The atmospheric aerosol was sampled in two campaigns (July–August 2021 and February 2022) on the terrace of Institute of Analytical Chemistry of CAS in Brno. Theoretical part of the study contains information about analytical methods for the characterization of aerosol, the experimental part describes used methods in detail and the results of experiments are discussed.
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