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Monitoring of inorganic contaminants in moravian white wines
Šebek, Richard ; Slavíková, Zuzana (referee) ; Pořízka, Jaromír (advisor)
This bachelor thesis is focused on monitoring of selected inorganic contaminants, especially metallic elements and macro elements, in Moravian white wines. The aim of this thesis is to compare the element composition of wines according to the geographical origin, different production system and vine varieties. Two spectrometric techniques were used for elemental analysis of wine samples: Inductively coupled plasma with mass spectrometer and inductively coupled plasma with optical spectrometer (ICP–MS and ICP–OES). Evaluation of the results was carried out using statistical method of variance analysis (ANOVA). Vanadium, copper, lead and magnesium were evaluated as statistically significant in at least one Moravian sub-region. No statistically significant results were found in other comparisons.
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Determination of selected metals in edible mushrooms in the Kladno district
ŠIMŮNKOVÁ, Eliška
The aim of this work was to determine the concentrations of rubidium, zinc, iron, copper, strontium and manganese in samples of edible mushrooms and to compare our results with other studies. The literary research contains brief information about mushrooms, soils, metals, used analytical method and research site. During the summer months of 2020 and 2021 twelve samples of seven edible mushroom species were collected from the forest between the former mines of Kladno for the purpose of the practical part. The whole practical part of the bachelor thesis was performed in the laboratory of the Department of Applied Chemistry, Faculty of Agriculture and Technology of the University of South Bohemia in České Budějovice. Measured values were recorded in tables and statistically processed. Through analysis we found out that a parasol mushroom belongs to mushroom species with the highest ability to accumulate metals. Among the analyzed samples we found the highest content of iron (1148 mg/kg), copper (150 mg/kg) and the second highest of manganese (339 mg/kg). On the other hand the least able to cumulate metals between analyzed mushroom species was red cracking bolete which contained the lowest contents of manganese (15 mg/kg) and strontium (1,6 mg/kg). The stink snake is worth mentioning because of its high strontium (10,1 mg/kg) and manganese (643 mg/kg) accumulation. Measured manganese content significantly exceeded the values measured in other analyzed samples.
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Využití litinových materiálů v konstrukci dopravní a manipulační techniky
HAKLOVÁ, Lenka
The content of this research work is devoted as comprehensively as possible to the issue of basic types of cast irons, from their origin as one of the iron alloys, to their characteristics, properties and use as a construction material in the field of transport and handling technology. The work is supplemented by information about iron as a chemical element, iron ores, metals, crystallographic systems and, last, but not least, a diagram of iron - carbon, which is directly related to cast iron
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Elemental analysis of selected types of herbal teas
Adámková, Petra ; Hraníček, Jakub (advisor) ; Šíma, Jan (referee)
In this bachelor thesis the concentrations of magnesium, potassium, manganese, zinc, copper, chromium, cadmium and lead in selected herbal teas and their infusions were determined. Teas from two competing producers on the Czech pharmaceutical market were selected for analysis. The aim of this work was a mutual comparison of selected tea samples in terms of their elemental content. An indicative study of the effect of water temperature and leaching time on the release of elements into the solution during the preparation of the pickle was carried out. The applied method included the decomposition of samples in a microwave device in the presence of concentrated nitric acid and analysis of the composition of the prepared solutions using ICP-MS. The results showed that the element contents differ according to the type of plant and according to the producer. Furthermore, it was proven that the leaching time has a greater influence on the release of elements into the solution than the water temperature. In this work, it was also verified that the ICP-MS method was suitable for determining the concentrations of all selected metals due to low detection limits. Key words Mass spectrometry, inductively coupled plasma, herbal teas, metals, microwave decomposition
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3D metal printing by wire welding methods
Přibyla, Dalibor ; Izák, Josef (referee) ; Sigmund, Marian (advisor)
This thesis presents the most commonly used technologies of 3D metal printing by wire welding methods, like WLAM, EBAM and WAAM. Deals with their principles, sub methods, applications, suppliers and also with current researches and trends, which are focused on deposition of thin layers. CMT technology is closely described, with attention on its certain kinds, like Cycle step, Advanced, Pulse Advanced, Pin and Braze+. Then, the CMT workplace at IMID DREAD, FME BUT is described by individual components, automatization and robotization. Final evaluation shows, that the chosen workplace is appropriate for required 3D print of magnesium alloys and overhanging structures, due to cold metal transfer technology and low purchase price.
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Paper, plastics and metals recycling
Kaireshev, Ruslan ; Benešová, Libuše (advisor) ; Doležalová, Markéta (referee)
The latest trends in the field of waste management and recycling show an annual increase in the proportion of municipal waste, especially the municipal solid waste folder, in total waste production in the Czech Republic and in the world. The constant pressure specified by latest amends in the waste and packaging legislation, regulation by the European Union directives on reducing the amount of waste deposited in landfills, pushing the waste management system to increase the rate of recycling of waste, especially of individual commodities such as paper, plastic, metal and cartons. Recycling has its advantages and disadvantages, the current challenge for expert public is to find ways of waste management in the future. Currently, expert public is interested not only with solution of recycling problems itself, but with possibilities of alternative forms of waste recovery. In 2010, thanks to the recycling of paper, plastics, glass and metals saved 23.3 million MJ of energy that may not be produced, which represents one percent of the total energy consumption of the Czech Republic. Recycling reduced the overall green gas emissions by less than one percent, corresponding to 0.96 million tonnes of CO2 equivalent (EKO-KOM). Key words : recycling, paper, plastic, metals
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Water and sediment chemistry of fluvial lakes of the Elbe River
Chalupová, Dagmar ; Janský, Bohumír (advisor) ; Jelínek, Emil (referee) ; Benešová, Libuše (referee)
The presented paper aims at the problems of fluvial lakes in middle course of the Elbe River which has been influenced by the human activity since the Middle Ages. The oxbow lakes which are extremely precious ecosystems contributing to the stability of the river ecosystem show not only the changes of the course of the Elbe River. With regard to sedimenting a great amount of pollutants, these lakes also tell about the industrial pollution to which the river was exposed mainly in the second half of the 20th century due to insufficient precautions on industrial sources causing contamination. 5 cut lakes between Hradec Králové and Mělník have been studied within this research. These lakes differ in the intensity of communication with the river, in the distance from significant sources of industrial pollution and in the use of nearby land. The research included morphometric and bathymetric measures, observation of hydrological regime, seasonal measures in the water column and regular analysis of surface water samples. Profiles of sediments in the length that the used technology allowed were sampled, so that older anthropogenic load could be found out. The amount of organic carbon and concentration of selected metal and arsenic (Ag, Cd, Cr, Cu, Fe, Hg, Mn, Pb and Zn) were stated apart from grain size...
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