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The study of contamination of forested areas of the Czech Republic by mercury
Trávníčková, Gabriela ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the issue of mercury in the environment. It focuses on determining the concentration of total mercury in edible mushrooms and in the soil in 12 localities in the Jeseníky Mountains. A single-purpose absorption spectrometer AMA 254 was used to determine the mercury content. The sites where sampling took place were divided into 6 sites with spruce stand and 6 sites with beech stand. No relationship was found between the type of stand and the amount of accumulated mercury in the mushrooms. On a representative sample of yellow-boletus mushrooms found in each locality, it was found that the higher the amount of mercury in the mushroom, the lower the amount of mercury in the soil. The fungi are therefore able to accumulate mercury from the environment. Thus, they can become a potential source of intoxication when ingested. The mobility of heavy metals in the soils depends on many soil properties (pH, carbon and sulfur content). Metals form more soluble compounds in lower pH environments. The soil pH was very low and the lower the soil pH, the higher mercury concentration in the soil. This fact could be supported by acid fallout. The relationship between the mercury content and the carbon content of the soil confirmed that carbon has the ability to bind mercury. The higher the amount of carbon in the soil, the higher the amount of mercury.
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Bioavailability of metals species in water ecosystem
Tandler, Ágnes ; Řezáčová, Veronika (referee) ; Vávrová, Milada (advisor)
Koncentrace volných kovových iontů je často jen malou částí celkové koncentrace kovu v prostředí. Přes tento malý obsah, je ve většině případů koncentrace volných kovových iontů klíčovým faktorem při určování biodostupnosti a toxicity pro organizmus. Membránová technika Donnan se používá k měření koncentrace volných kovových iontů a v této diplomové práci je ověřena pro směsi kovů (Pb + Cu) při absenci a přítomnosti malých organických ligandů. Olovo a měď jsou environmentálně důležité kovy díky své toxicitě a rozdílným vazebným vlastnostem ve vztahu ke studovaným ligandům.
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Determination of organic tin compounds in the environment
Fojt, Jakub ; Mravcová, Ludmila (referee) ; Řezáčová, Veronika (advisor)
Organotin compounds are one of the most produced and most used organometallic compounds. Some of these substances are endocrine disruptors, persistent organic polutants and their high toxic effects are observed. That’s why their presence in the environment caused by human activity could endanger many organisms. The aim of this thesis is summarize their properties and their occurrence in the environment. Then the quick, easy and relatively cheap method for determination of trialkyltin compounds in heavily poluted aquatic sediments using capillary zone electrophoresis is developed.
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Pesticide glyphosate and possibilities of its determination
Stará, Kristýna ; Mravcová, Ludmila (referee) ; Řezáčová, Veronika (advisor)
This bechelor thesis deals with determination of glyphosate employing capillary isotachophoresis technique. The literature review is devoted to pesticide, their distribution and use, properties and methods for the glyphosate determination, capillary zone isotachophoresis and its use. Experimental part focuses on the application of capillary isotachophoresis for determination of glyphosate, for determination of glyphosate in commercial preparations and testing of glyphosate sorption in soil.
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Assessment the impact of the application of excavated sediments from the dam Luhačovice on the content of risk elements in arable soil
Kratěnová, Pavla ; Komendová, Renata (referee) ; Řezáčová, Veronika (advisor)
This diploma thesis focuses on an issue concerning an excavated sediment application on an arable soil and its impact on the soil quality based on a particular case of a deposition of the sediment from the dam Luhačovice on an adjacent agricultural area. The theoretical part of this thesis is focused on a soil and sediment characteristics and functions, contained risk elements, sampling methods, determination possibilities of particular risk elements and a description of conditions which emerged from a need for the deposition of sediment obtained during scavenging of the dam Luhačovice. In the experimental part was described the process of sampling, samples processing and determining of concentration values for chosen risk elements (Cd, Cu, Hg, Ni, Pb) using flame or electrothermal atomic absorption spectrometry methods. This part also contains an evaluation of obtained results and a validation of an approval for the sediment deposition.
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Use of derivatization methods in gas chromatography
Kaprinay Bréda, Boglárka ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
This study is focused on verifying the possibility of derivatization in gas chromatography for the determination of fatty acids in oil samples and on the use of derivatization for the determination of organic substances in a sample of vine seed extract. The theoretical part deals with the characteristics of individual analytes. In the next section derivatization methods and transesterifications for fatty acid determination are described. The last chapter deals with the basic knowledge of gas chromatography and its instrumentation. The experimental part was divided into three chapters: analysis of fatty acids by transesterification, determination of mono- , di-, and triglycerides by derivatization and analysis of grape seed extracts. Three types of oils were analyzed in the experimental part: poppy, linseed and nut oil. The most common fatty acids in plant oils are palmitic, stearic, oleic, linoleic and linolenic acids. The optimization method was carried out using the derivatizing agent MSTFA. The determination of fatty acid methyl esters was measured on a gas chromatograph with a flame ionization detector. To confirm the presence of fatty acids, additional analysis was used on gas chromatograph with a mass spectrometer. Analysis of the grape extract was also performed on GC/MS. The method was most convenient using MSTFA, BSTFA and BSA+ TMCS derivatizing agents.
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Determination of tensides in waters by separation methods
Brestovská, Marta ; Řezáčová, Veronika (referee) ; Čáslavský, Josef (advisor)
Surfactants are synthetically made surface-active agents contained in washing and cleaning products. They decrease the surface tension and remove dirt. Surfactants can be divided into three basic classes: anionic, cationic and non-ionic. Thanks to the massive use they penetrate into waste water and can disturb the environment. This diploma thesis deals with the occurrence of surfactants in water and their determination by separation methods, especially LC / MS.
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Determination of organic acids in wine
Michálková, Kateřina ; Mravcová, Ludmila (referee) ; Řezáčová, Veronika (advisor)
This bachelor thesis deals with determination of organic acids in wine by capillary zone isotachophoresis method. The theoretical part is devoted to the properties of wine, its composition, its benefit to human health and capillary zone isotachophoresis and its practical use. The practical part deals with determination of organic acids in wine by capillary zone isotachophoresis. Organic acids are determined in three phases of white and red wine production.
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