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Determination of titanium dioxide nanoparticles in personal care products
Košík, Juraj ; Čáslavský, Josef (referee) ; Vávrová, Milada (advisor)
Předkládaná diplomová práce se zabývá extrakcí nanočástic oxidu titaničitého z produktů osobní péče, konkrétně opalovacích krémů a následnou charakterizací těchto částic. Počet komerčně dostupných produktů s obsahem nanočástic TiO2 se neustále zvyšuje a to se sebou přináší potřebu vyhodnotit potenciální osud a nepřímou expozici TiO2 nanošástic o různých velikostí a tvarů a zkoumat jejich celý životní cyklus. Bylo zkoumáno použití ultrafiltrace a ultracentrifugace jako extrakční metody. Dvě metody pro extrakci TiO2 nanočástic byly vyvinuty a aplikovány na vzorky opalovacích krémů. Extrahované částice mohou být použity pro ekotoxikologické studie, případně experimenty v mesokosmu. Velikost částic byla stanovena pomocí metody dynamického rozptylu světla a transmisní elektronové mikroskopie.
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Hormones in waste waters
Petrušová, Pavlína ; Vávrová, Milada (referee) ; Čáslavský, Josef (advisor)
This bachelor thesis gives the overview of waste water contaminants of steroid hormones type. A short description of these compounds and of their physical-chemical properties is given and sources of these substances in the environment are characterized, as well as their impact on organisms The fate of these compounds and methods used for their isolation from environmental compartments methods of their final analysis are characterized.
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Structural stury of carboranes by mass spectrometry
Navrátilová, Romana ; Vávrová, Milada (referee) ; Čáslavský, Josef (advisor)
Boron cluster compounds are substances clearly synthetic, which don't exist outdoors. This group covers boranes, heteroboranes and their derivatives. They are synthesized and examined mostly for their extraordinary structural and bonding properties. Their study also brought many remarkable findings and even allowed practical use of these compounds in science and technology. This thesis is focused on the application of mass spectrometry for the identification of boranes and heteroboranes and on the study of their fragmentation mechanisms using tandem mass spectrometry on spherical ion trap.
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Application of passive sampling for the analysis of hormones in drinking water
Remerová, Martina ; Mravcová, Ludmila (referee) ; Čáslavský, Josef (advisor)
The thesis focuses on the use of passive sampling during an analysis of hormones in drinkable water. In the theoretical part there are described selected passive samplers and the sample of the type of POCIS is described at fuller length. The next chapter engages with steroid hormones and an input of estrogenic hormone into the environment. The thesis contains chapters dealing with possibilities of the determination of hormones in water. It is specialized on the analysis of drinkable and surface water. In the last chapter of the theoretical part there are introduced water works where samples for an experimental assessment were collected from. The experimental part of the thesis presents the specification of the extraction of analytes and an adjustment of used device. In the thesis there are specific calibrations for individual assessment of hormones. The results of the assessment for each collection point are ordered to a well-arranged table. Increased levels of targeted estrogens were not approved in most of sampling points.
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Analytical methods applied for the evaluation of environmental contamination by uranium ore mining
Bílek, Jiří ; Holubová, Zuzana (referee) ; Čáslavský, Josef (advisor)
This thesis deals with the testing procedures used in monitoring of environmental contamination after uranium ore mining in the uranium mine in Dolní Rožínka. It deals with the determination of radioactive elements radium, uranium and radon. The methods used for the determination of radioactive elements in mine laboratory in Dolní Rožínka are described. The thesis also mentions other applicable methods for determination of uranium. The metods of determination of manganese, iron and other metallic elements are also summarized in brief.The values of concentrations of monitored analytes in selected locations are presented at the end of the thesis. These values, which were provided by laboratories in Dolní Rožínka, are valid for 2010.
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Photocatalytic water splitting by oxide semiconductors modified with graphen/graphenoxide
Marek, Jiří ; Čáslavský, Josef (referee) ; Cihlář, Jaroslav (advisor)
This master thesis deals with the topic of alternative production of hydrogen as the energy carrier of the future. The primary focus is on the production of hydrogen based on photocatalytical water splitting in the presence of semiconductor materials (especially modified and unmodified TiO2). The aim of the thesis is a synthesis of nanostructured oxide, graphene/graphene oxide particles and its composites, and a study of its structures and photocatalytical properties regarding photolysis of water. Products of the syntheses are described from the point of view of phase composition, surface area and photocatalytical activity. The main output of the thesis is a discussion of the influence of alkaline complex forming reagents on the hydrothermal low-temperature synthesis of biphasic TiO2, and a study of the influence of graphene/graphene oxide modification on photocatalytical activity of biphasic TiO2.
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Determination of selected musk compounds in biotic samples
Blahová, Eliška ; Čáslavský, Josef (referee) ; Vávrová, Milada (advisor)
Musk compounds (MUSK) or synthetic fragrances are organic substances commonly used as fragrant constituents of detergents, soaps, cosmetics, personal care products, industrial and in-house cleaning agents, industrial plasticizers, chewing tobacco and fresheners. The big attention is pushed ahead studying these compounds, their fate in different parts of ecosystems and studying their characteristics at present, because musks infiltrate many environmental components, particularly aquatic and marine ecosystems, through their large application and their ability to be perzistant. This diploma thesis was focused on four synthetic “classical” fragrances used over the world. The aim of this study was to perform a method optimisation for the determination of selected fragrances in biotic matrix. There was made an evalution of ability of selected water treatment plant to clear away musks from water, these results were used for evaluating contamination measurement of aquatic ecosystem. The identification and quantification of analytes was carried out by high resolution gas chromatography - mass spectrometry (HRGC/MS).
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Study of degradation of biocompatible copolymers
Oborná, Jana ; Čáslavský, Josef (referee) ; Vávrová, Milada (advisor)
This diploma thesis is focused on biocompatible polymers degradation study. Copolymers were studied based on poly(lactic-co-glycolic) acid and poly(ethylene glycol) PLGA-PEG-PLGA and further these copolymers modified with itaconic acid ITA-PLGA-PEG-PLGA-ITA. This paper investigated the influence of pH phosphate solution on the degradation of polymers. Degradation of polymers occurred at 37 °C in phosphate solution with pH 4.2, 7.4 and 9.2. High performance liquid chromatography with UV-VIS detection of diode-array type was used for quantitative determination of lactic acid and glycolic acid as the final degradation products. For qualitative identification of additional degradation products were used tandem connection liquid chromatography and mass spectrometry. Gel permeation chromatography with refractive index detector was used to determine the molecular weight decrease polymer chain after the degradation.
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