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Possibilities of removing metals from drinking water sources by water treatment processes
Marzinová, Kristýna ; Látal,, Milan (referee) ; Biela, Renata (advisor)
In my diploma thesis I focused on the issue of metals, their occurrence in drinking water sources in the Czech Republic and the possibility of their removal by water supply processes. Heavy metals degrade the quality of water resources, so more complex water treatment technologies are needed. The first part describes the metals, their properties, their significance and occurrence in water, then the possibility of removing metals using water supply processes. In the practical part of the diploma thesis I performed a laboratory experiment to remove iron, manganese and nickel by adsorption on selected filter materials, which are Filtrasorb F100, Filtrasorb F 400, Bayoxide E33 and GEH. The experiment was used to compare the effectiveness of selected sorption materials.
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Comparison of Selected Adsorbents for Removing Metals from Water
Moravčíková, Světlana ; Biela, Renata
Various metals and their compounds are among the number of substances that currently pollute drinking water sources. A laboratory experiment was performed to compare selected sorption materials for removing metals from water. Filter columns filled with selected sorption materials GEH and Bayoxide E33 were used for experimental comparison. The metals arsenic, nickel and lead were removed from the water by sorption. Based on several criteria, Bayoxide E33 was evaluated as a more suitable material.
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Mobility of metals in peat profile
Shevchenko, Anna ; Mihaljevič, Martin (advisor) ; Vaněk, Aleš (referee)
There are a lot of scientific publications, where the main target of research is mobility of metals in peat profile. For a brouder overview, in this Barchelor thesis, are described results of studies from geographically distant localities. But even with regard to this variability, there are some common trends in the mobility of certain metals. Numerous scientific publications suggest, for example, the ability of Pb to immobilize in peat and remain relatively immobile in the vertical direction. In contrast, radionuclides, as suggested, tend to migrate to the lower parts of peat profile. From mobility characteristics of various metals in peat, we can conclude about their applicability in atmospherically deposed material dating. It can also be useful for predicting the behavior of toxic elements in peat with regard to changes in physicochemical characteristics. Key words: metals, peat, mobility
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Workplace for measuring electrochemical potential of metals
Cápal, David ; Kazda, Tomáš (referee) ; Libich, Jiří (advisor)
This bachelor's thesis describes the issues related to corrosion in electrical engineering. Thesis describes corrosion itself, historical mentions and causes. It also deals in deatail with electrochemical corrosion and the behavior of ions at the electrode-electrolyte interface together with the redox processes that accompany them. This thesis describes the origin and use of these electrochemical reactions as a way of creating electrochemical potential in liquid electrolytes at the metal-electrolyte interface. Thesis also describes measuring methods and evaluation of measured results using polarization curves and Tafel diagrams.
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Návrh kovového nábytku
Dembinná, Magdaléna
The Master´s thesis consists of two parts. In theoretical part are processed topics like metal division, their qualities, metal processing and metal surface adjustment. We can find here the describtion of selected typological group, storage furniture. Practical part contains research and proposal from the first sketches to the visualization. There is also the describtion of materials, surface adjustment and proposal construction.
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Nanouhlíkové materiály pro bioaplikace a detekci těžkých kovů =: Nanocarbon materials for bioapplications and heavy metals detection /
Bytešníková, Zuzana
The aim of this thesis was the synthesis of carbon nanomaterials and their composites for environmental applications, application as an antibacterial agent, and crop protection. As the basic constituent of all prepared nanomaterials, graphene oxide (GO) prepared by the modified Hummers method was successfully used. In order to improve the desired properties, the prepared GO was further reduced and modified with magnetic nanoparticles (MPs) and nanoparticles (NPs) of metals or metalloids to form composites. In the prepared nanocomposites, the synergistic effect of graphene oxide and nanoparticles was utilized. In the case of nanocomposite formed from reduced graphene oxide (rGO) and MPs, this composite was used to bind Se (IV) as a heavy metal from an aqueous medium. In addition, the advantage of this material was its reusability after a recovery in ethanol. To protect agricultural crops against Xanthomonas euvesicatoria (X. euvesicatoria), which causes the bacterial spot disease of tomato and pepper and considerable economic casualties, nanocomposite containing GO and copper and silver NPs was used. This nanocomposite was selected for application to tomato and pepper plants after previous microbiological tests in vitro.
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Vliv lesa na migraci a sedimentaci rizikových prvků a vybrané environmentální problémy
Juřička, David
The research of the dissertation thesis was focused on the ability of forests to activate and immobilize metals in the environment with their huge grants from deep mining of mineral resources. The research was be located in the area of Rožná with ongoing uranium mining, and area of Olší with ended uranium mining in the Czech Republic. During the years 2014 and 2015 was at the alluvial streams of Nedvědička (Rožná) and Hadůvka (Olší) recipients of pollution by radionuclides and metals from mining, taken in spring and autumn aspect of the overall 380 samples of leaves from trees, herb layer and river sediments. The samples were analyzed by the XFR and ICP-OES methods. In the organic matter were found such as elements Al, Cl, Cu, Cr, Fe, Mn, Mo, Ni, Rb, S, Sr, U, Zn and Zr, in many cases at high concentrations corresponding to polluted areas in the mining or industrial areas. A statistically significant difference in the concentrations of chemical elements in the fytomasss and river sediment between the upper, middle and lower stream areas of interest was not found. In the area of Nedvědička were found higher concentrations of a greater range of metals than in the area of Hadůvka. In the area of Hadůvka were by ICP-OES found significantly higher levels of uranium in the leaves than in the area of Nedvědička, reaching up to 34.86 mg.kg-1 in the dried material.The seasonal dynamics of the content of chemical elements in fytomass was confirmed. The species composition of the forest growth in the areas of interest with a predominance of Picea abies and the type of management has been evaluated as unfavorable for immobilization of metals in the environment. In the area of Nedvědička were suggested corrective actions - planting vegetation with a predominance of Fagus silvatica which should have a beneficial effect on soil and water pH by a suitable character of waste and contribute to the spread of inhibition of metals in the environment. In the area of Hadůvka are the suggested measures focused on the redevelopment of existing vegetation with a predominance of Picea abies on vegetation with a predominance of deciduous trees, especially Fagus silvatica, in order to adjust gradually the pH of the soil and thereby reduce the mobility of metals in the environment.
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Vliv akumulace manganu na vybrané rostliny
Švec, Pavel
In this work we investigated the effect of high doses on the agriculture important crop plants (Brassica napus, Hordeum vulgare, Zea mays), herb Matricaria chamomilla and freshwater microalgae Scenedesmus quadricauda. In particularly, we studied the growth rate, activity of antioxidant enzymes, and the amount of some secondary metabolites. We have found that high doses of manganese negatively influenced the growth, which resulted in a reduction of biomass which we observed in all studied groups, except algae. Manganese (Mn) is accumulated in roots and part of such absorbed Mn is transported to the shoot system. In the plants, the distribution of Mn is more balanced compared to copper and cadmium. We observed changes in the content of aliphatic organic acids, and the total amount of thiols. Higher activity was determined in several antioxidant enzymes according to the kind of plant. Abundance of manganese has been considered more toxic for the Brassica rapa than for the ontogenetic older Matricaria chamomilla, where we indicated a higher tolerance to the high concentration of Mn. We also found that the nitrogen oxide showed the positive effect on the toxicity of Mn and improved the plant viability. This improvement was reflected by decrease in uptake of Mn ions, decrease of ROS production and lipid peroxidation and also better growth parameters in the tested plants. The bioavailability of the Mn was influenced by pH however the uptake of Mn was not affected. We also found out that competition between Mn2+ and Ca2+ occur in the both land plants and also freshwater microalgae Scenedesmus quadricauda.
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Study on the Reactivity of Extracellular Polysaccharides Produced by Bacteria
Vacková, Barbora ; Smilek, Jiří (referee) ; Kalina, Michal (advisor)
This bachelor thesis deals with the reactivity of bacterial extracellular polysaccharides. The experimental part deals with extracellular polysaccharide FucoPol. Due to the presence of acyl groups, the polymer has an anionic character and can promote interactions with other positively charged substances. In this bachelor thesis interactions of FucoPol with metals were studied. For measuring, an isothermal titration calorimeter was used, and sorption experiments were performed. The main objective of the work was optimization of conditions for measuring interactions between metals and FucoPol. Connection of metal cations to FucoPol matrix were confirmed by titration calorimetry and sorption experiments. The interaction rate was different depending on the metal which was used. Co2+, Pb2+ a Zn2+ ions showed very weak binding, otherwise Cu2+ a Fe3+ ions had high affinity for the studied biopolymer. FucoPol, as a biodegradable biopolymer, can be in the future one of important industrially produced polysaccharides. It could be used for packaging, biofuel production and production of anti-inflammatory and immune-boosting drugs.
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Complex characterisation of medical herbs and study of their utilization in food industry as a source of functional components
Burdějová, Lenka ; Kráčmar, Stanislav (referee) ; Šilhár, Stanislav (referee) ; Polovka, Martin (advisor)
Presented thesis deals with the complex characterization of extracts from medical plants using spectroscopic and chromatographic techniques, with emphasis on the influence of solvent, post-harvest treatment of the sample, location and year of production on selected parameters. Part of the work is devoted to application of selected extracts from medical plants in suitable form into beverages. The thesis is divided into two parts. At the first part of the work combination of electron paramagnetic resonance, ultraviolet visible spectroscopy, liquid chromatography and inductively coupled plasma optical emission spectrometry was applied for characterization of aqueous, ethanol and dimethylsulfoxide extracts from 10 selected medical plants, which were collected from two different locations during two years (2015, 2016) and post-harvestly treated by two ways (freezing, drying). In total, 39 parameters were determinated: namely total phenolic compounds content, total flavonoids content, 14 specific phenolic compounds, colour characteristics in the CIE L*a*b* system (L *, a*, b *, C*, h°, BI), radical-quenching activity using the cation radical of the 2,2'-azino-bis- (3-ethylbenzothiazoline-6-sulfonic acid), antioxidant/pro-oxidant activity using the spin trapping technique in the presence of 5,5-dimethyl-1-pyrrolin-N-oxide (DMPO)/potassium peroxodisulphate and content of 15 minerals (Al, As, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, P, Pb, Zn). The results confirmed that the studied parameters of medical plants are influenced by the extraction system, post-harvest treatment of samples, year of production, origin of samples (locality) and species composition. It has been shown that the type of extraction solvent significantly affects the composition of the extracts. On the basis of these analyzes, for food application – the isolation of the main functional components (phenolic compounds, flavonoids) –50% ethanol, post harvest treatment by drying and samples of Mentha piperita, Melissa officinalis, Hypericum perforatum and Salvia officinalis were selected. The second part of the thesis was focused on the application of selected extracts of medical plants to beverages (syrups). The above mentioned plants, 25% ethanol instead of 50% ethanol (due to the limitation of the ethanol content in final raw material), were selected for the application. At first, extraction of medical plants was optimized. Suitable ratio of material and solvent (1:10), extraction time (8 h) and herb absorbency (50–62 %) were determined. The prepared extract after filtration was applied to the syrup concentrate in different ratios to produce one-species syrups and further sensorially tested to select the suitable recipe, the best flavour and basis for the production of two-species syrups. The mint syrup was the most tasty and generally the most acceptable one-species syrup, and sage syrup was selected as the basis for two-species syrups. Further, the most appropriate recipes of the two-species syrups were chosen, the most sensorially acceptable one was selected and further tested if it would be appropriate to colour them. Preferentially, it has been found that it is not necessary to colour two-species syrups. On the basis of the sensory analysis, it has been found that peppermint and sage-peppermint syrups were the most tasty and acceptable syrups, which could be, after further testing, produced industrially to enrich the food market.
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