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Monitoring of arsenic forms in foodstuffs
Harkabusová, Veronika ; Hrstka, Miroslav (referee) ; Vitoulová, Eva (advisor)
The diploma thesis is dealing with monitoring of arsenic in foodstuffs. The aim of this thesis is the determination of arsenic in samples of fish and rice and the study of forms, in which arsenic occurs, using speciation analysis. Arsenic is known as a toxic element, but its measure of toxicity depends on the chemical form it occurs in. Arsenic is present in the environment naturally or it gets in the environment by human activities. Complete characterization of arsenic compounds is necessary to understand intake, accumulation, transport, detoxification and activation of this element in the natural environment and living systems. The field of arsenic speciation analysis has grown rapidly in recent years, because determination of the total element content is not sufficient in the case of arsenic. Speciation method was done using separation by high performance liquid chromatography and detection by atomic fluorescence spectrometry with hydride generation. Extractable arsenic was present in the form of nontoxic arsenobetaine in all analysed samples of fish. In samples of rice there was confirmed the presence of toxic inorganic species of arsenic, esspecially As (III), but their concentration was at low level.
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Comparison of extraction methods for agriculture soil elemental analysis
Štursa, Václav ; Vespalcová, Milena (referee) ; Diviš, Pavel (advisor)
This bachelor thesis handles with optimization of preparation process of soil samples from vineyards for elemental analysis performed by ICP-MS. First part of the thesis deals with element analysis and its usage in agrotechnics and viticulture, description of toxic and nutrition properties of individual elements and legislation defining appropriate concentration limits of elements in agricultural land. Next part describes commonly used methods for elemental analysis such as AES, AAS, roentgen fluorescence spectrometry and ICP-MS. Finally, sampling methods and methods for sample preparation such as digestion and extraction are described. Experimental part follows up comparison of selected extraction methods (2M HNO3 extraction, temperature assisted 2M HNO3 extraction, aqua regia extraction and microwave-assisted digestion using mixture of HNO3 and H2O2). These methods were applied on certified reference materials. Extracts were analysed by ICP-MS technique Best results were achieved by 2M HNO3 extraction. This extraction method was subsequently applied on real soil samples from vineyard.
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Rhodium in the environment
Ondreášová, Klára ; Nevrlá, Jana (referee) ; Komendová, Renata (advisor)
This bachelor thesis focuses on the characteristic of rhodium, its use in the automotive industry, the occurrence in environmental compartments (air, soil, vegetation, water), accumulation and transformations. In this thesis there are also described methods of sampling for determination, the types of sample preparation, separation and preconcentration techniques necessary prior to instrumental analysis. The work also focuses on the most commonly used analytical methods of rhodium determination, which are spectrophotometric methods, AAS, ICP-AES and ICP-MS.
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Recycling of steel-works flue dusts from electric arc and inductive furnaces
Huczala, Vít ; Koplík, Jan (referee) ; Šoukal, František (advisor)
This bachelor thesis deals with an application of electric arc furnace dust from steel production as secondary raw material for production of zinc and industrially process able zinc products. In this thesis the dust was processed by methods based on various physical and chemical properties. The most experiments were performed during the treatment with leaching in sulphuric acid. For this leaching the optimal concentration of sulphuric acid and the optimal ratio acid:dust was determined. The final products were prepared by precipitation or by evaporation of filtrate obtained after leaching. There were also used hydrolysis of dust and oxidative precipitation of filtrate during the processing. These steps led to increase of the quality of the final products. The price balance was also performed for the prepared products.
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Substituted polyaromatic compounds in environmental components
Kubalík, David ; Mravcová, Ludmila (referee) ; Vávrová, Milada (advisor)
This work is focused on substituted polycyclic aromatic hydrocarbons (PAHs) in environmental compartments. The thesis examined the development of these compounds and their entry into the ecosystem. Due to their proven negative characteristics to be addressed also their toxicology. The next section discusses the appropriate methods, including sampling, sample preparation and final determination. The conclusion of this work forms draft standard operating procedure for their determination.
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Determination of ergosterol content in brewing materials
Matyáš, Martin ; Ing.Pavla Kožušníková, Ph.D. (referee) ; Benešová, Karolína (advisor)
Presented bachelor’s thesis is focused on determination of ergosterol content in barley and malt. In theoretical part the presence of ergosterol in barley and malt has been elaborated, the purposes of its determination, detailed overview of previously applied methods of extraction from samples of barley and malt as well as other biological materials and methods of quantification. Practical part is focused on optimizing of extraction and determination of ergosterol by high performance liquid chromatography with diode array detection (HPLC – DAD).
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Multiresidual methods for the determination of pesticides in waters
Matušková, Monika ; Kubíčková, Kristýna (referee) ; Vávrová, Milada (advisor)
This bachelor´s work of theoretical character deals with multiresidual determination of pesticides in water. It is especially focused on pesticides generating residues in surface water, which - due to their toxicity and persistence in environment - require goal-directed monitoring. The division of pesticides is stated, and their properties, toxicity and elimination process are described in the work. Furthermore, possibilities of analytical determination, especially the methods of gas and liquid chromatography are introduced here. In the last chapter, the complete analytic procedure for determination of organochlorine pesticides is described.
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Exploitation of Infrared Spectroscopy for Determination of Polymer Admixtures in Cement Composites
Novotný, David ; Hodná, Jana (referee) ; Petránek, Vít (advisor)
In the thesis deals with the possibilities of determining the amount of polymer additives FTIR. Are described in detail various polymeric ingredients which are used in concrete mixtures. Then thoroughly discuss the use of recyclable polymer additives polyvinylbutyral (PVB), its production, the primary use, recycling and subsequent use. Next, I will discuss methods for determining the amount of polymer in the substance. In the experimental part were blended with several samples with different percentage for each polymer. Where we conducted appropriate tests and assessments, and individual samples are briefly described, evaluated and compared.
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Problems of phenols in water
Tylichová, Petra ; Čáslavský, Josef (referee) ; Doležalová Weissmannová, Helena (advisor)
This bachelor`s thesis deals with the issue of phenols in the waters. The theoretical part summarises the information about the characteristics of the phenols, its use, appearance in the environment, and its effects on human health. There are described methods of determination these substance in the waters. The last chapter disserts on possible methods of eliminating the phenols from the aqueous environment with special attention paid to the adsorption method. Part of this thesis is also dedicated to the chlorinated phenols which originate from chlorination of the phenolic waters and which cause the sensory interferences of the waters. The experimental part of this thesis is dedicated to removing the phenol from a model water through the adsorption into a powdery active carbon Norit SA SUPER.
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