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Infrared spectroscopy of thin films
Kiss, Andrej ; Čáslavský, Josef (referee) ; Čech, Vladimír (advisor)
Cílem této bakalářské práce je literární rešerše v oblasti tenkých vrstev, plazmochemické depozice z plynné fáze a infračervené spektroskopie Fourierovou transformací, a měření infračervených spekter tenkých vrstev a charakterizace jejich chemické struktury na základě změřených spekter. Pomocí infračervené spektroskopie Fourierovou transformací bylo měřeno pět vzorků tenkých polymerních vrstev z tetravinylsilanu, vytvořených na křemíkovém substrátu pomocí plazmochemické depozice z plynné fázi s efektivním výkonem v rozmezí od 2 W do 150 W. Měření odhalilo chemické vazby přítomné ve vzorcích a jak se struktura měnila s měnící se efektivním výkonem. Snížení absorpčních pásů s přítomností vodíku naznačuje zvýšení zesítění se zvýšeným efektivním výkonem. Také snížení absorpčních pásů s přítomností křemíku poskytuje důkaz pro zvýšení poměru C/Si. Tyto výsledky nám pomáhají porozumět charakteristikám těchto tenkých vrstev a přispívají k pochopení procesu plazmochemické depozice z plynné fáze.
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Monitoring of the plasmachemical process using mass spectrometry
Ondra, Zdeněk ; Čáslavský, Josef (referee) ; Čech, Vladimír (advisor)
This bachelor thesis deals with plasma-enhanced chemical vapor deposition (PECVD) and the use of mass spectrometry to monitor the processes in plasma during the deposition of thin film. Tetravinylsilane plasma was used in the process of forming a thin film on the silicon wafer. The background of the spectrometer, the residual gases in the plasma reactor at basic pressure were characterized and the plasma polymerization process was monitored. This process was monitored with increasing effective power (2-150 W). The obtained mass spectra were assigned and described in detail. The plasma species that showed the greatest change were then characterized as a function of time during film deposition.
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Monitoring of air quality in the Ostrava industrial agglomeration
Krejčí, Blanka ; Dombek,, Václav (referee) ; Holoubek,, Ivan (referee) ; Čáslavský, Josef (advisor)
Presented thesis deals with the evaluation of air quality in Ostrava industrial area, especially with regard to highly concentrated suspended particles and sorbed on them toxic polyaromatic hydrocarbons. Their above-limit concentrations are the main cause of negative effects on the health of humans and other organisms in one of the most outstanding European "hot- spot"regions, in the industrial agglomeration of Ostrava. The first part of the work is devoted to the evaluation of pollutant concentrations and contributions of identified types of air pollution sources in the wider influence area of a large industrial source in the Ostrava region. It was confirmed the concentrations of all pollutants show very significant inter-seasonal differences between the warm and cold parts of the year. The measured concentrations of PAHs in the cold season were 3 to 5 times higher than in the warm season. Less pronounced differences in concentration levels were seen between day and night samples. The air-pollution load was highest at the Radvanice site, compared to Vratimov and the background area of Poruba. The pollution caused by suspended particles originating from the emissions of the industrial complex in the annual scale contributes significantly to the resulting air quality image on the site, but is not an exclusive source. Other identified sources of the contributions to the PM2.5 concentrations are regional sources and operating seasonally sources (local heating). The second part of the thesis is an assessment of the character and regularities of air mass transmission in the ground-level layer of the troposphere in the Czech-Polish border area, as regional and long-range pollution transport plays a significant role, manifested in the resulting reduced air quality. The contribution of cross-border pollution sources is an important component of often alarming concentrations of atmospheric pollutants, especially during winter smog situations. It was shown within the northeast steady flow is dominated by the shift of higher concentrations of suspended particles from Poland to the Czech Republic. On the other hand, with the opposite prevailing direction of steady flow, particle concentrations on the Polish side of the territory are not increasing dramatically. At least half the year there are situations with variable wind direction, or low flow velocities during which the entire area on both sides of the border there are maximum concentrations of particles, including sorbed polyaromatics with the most serious health effects.
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Chemical analysis of organic residues in archaeological ceramic vessels
Bunžová, Aneta ; Mravcová, Ludmila (referee) ; Čáslavský, Josef (advisor)
The presented bachelor thesis deals with the analysis of organic residues in archaeological ceramic vessels. Apart from theoretical characterisation of residues, the thesis focuses on the possibility of the extraction of residues and subsequent analysis, which is executed on real samples from archaeological sites. In the research, two different derivatizational reagents were used for the subsequent determination using the technique of gas chromatography in combination with mass spectrometry (GC/MS). The thesis endeavours to certain extent to sketch the diet of the users of the analyzed ceramic vessels.
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Analysis of biochar aqueous extracts by separation methods
Tučková, Dominika ; Čáslavský, Josef (referee) ; Mravcová, Ludmila (advisor)
This master's thesis deals with the analysis of biochar extracts by separation methods. All analyzed biochar was produced from waterworks sludge by microwave pyrolysis. The aim of the thesis is the optimization of the sample preparation method and its analysis in a laboratory environment. With the ever-growing world population, the problem of a sustainable economy in both agriculture and waste management is becoming increasingly urgent. This fact has led most countries to consider promoting the so-called Circular Economy. The use of sewage sludge as a feedstock for biochar production is perfectly in line with this strategy. So far, however, the short term and the long term benefits and risks of using biochar have not been sufficiently described. Potentially hazardous organic substances were extracted from the biochar extracts by three techniques: liquid-liquid extraction, solid-phase extraction, and solid- phase micro-extraction. The obtained samples were analyzed using the GS-MS/TOF method. The individual methods were compared. Several biochar samples from WWTP Brno and WWTP Drahovice were selected and analyzed to verify the suitability of the selected sample analysis method.
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Regulation of Epithelial-Mesenchymal transition by the ERK pathway.
Čáslavský, Josef ; Vomastek, Tomáš (advisor) ; Brábek, Jan (referee) ; Gregor, Martin (referee)
Typical epithelium is uniformly polarized solid structure defined by the presence of cell-cell contacts that are connected to well-organized network of actin cytoskeleton. While epithelium is considered to be rather static, during embryogenesis or cancer development epithelial tissues undergo considerable dynamic changes in their integrity that are characterized by loss of epithelial polarity, disruption of cell-cell adhesions and gaining mesenchymal or mesenchymal-like migratory phenotype. These changes, collectively termed as epithelial-mesenchymal transition (EMT), allow cells to effectively invade surrounding tissues and are considered to be a main factor underlying the formation of metastatic cancer. The MAPK/ERK cascade, comprised of protein kinases Raf, MEK and ERK, induces the breakdown of epithelial integrity and cell autonomous migration in various cell lines. In the ERK pathway, ERK is an effector protein kinase which, depending on the cellular context, phosphorylates a number of different substrates. Spatiotemporal phosphorylation of specific constellation of ERK substrates drives specific biologic outcome. The question arises whether, during conversion of multicellular epithelium to autonomously migrating cells, ERK regulates a "master" controller or whether the ERK regulatory function...
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Degradation of Heat Transfer Fluids in Thermal Solar Systems and Propane-1,3-diol as a New Option
Mikšík, František ; Professor, Takahiko Miyazaki, (referee) ; Skolil, Jan (referee) ; Tocháček, Jiří (referee) ; Čáslavský, Josef (advisor)
Stárnutí teplonosných kapalin na organické bázi je dlouhodobým problémem, který je znám od počátku jejich používání. První část této disertační práce je tak věnována případové studii funkčního experimentálního systému, který byl jako nový naplněn teplonosnou kapalinou na bázi propan-1,2-diol a pozorován po období 7 let. Pro analýzu stárnutí kapaliny v tomto systému byly sledovány základní provozní vlastnosti kapaliny jako jsou hustota, viskozita, teplota tuhnutí, pH a obsah kovů. Skrze tyto vlastnosti tak bylo sledováno stárnutí kapaliny nepřímo. Přímé sledování stárnutí bylo posléze provedeno analýzou degradačních produktů, jako jsou organické kyseliny a změny ve složení směsi pomocí izotachoforézy a hmotnostní spektrometrie. Pro srovnání byly taktéž analyzovány vybrané vzorky z několik dalších systémů plněných identickou kapalinou s prokazatelně pokročilou formou degradace. V druhé části práce jsou představeny základní fyzikálně-chemické vlastnosti směsí propan-1,3-diolu s vodou a jejich analytické hodnocení a matematické modelování pro universální použití jakožto nového základu pro nemrznoucí teplonosné kapaliny. Na základě dostupných informací je pak hodnocena použitelnost této směsi. Výhoda propan-1,3-diolu je spatřována především ve výrobě z obnovitelných zdrojů a v některých fyzikálních a chemických vlastnostech, které dle dosavadních poznatků předčívají doposud používané glykolové směsi.
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Determination of TauroLock stability
Matejčíková, Eva ; Mravcová, Ludmila (referee) ; Čáslavský, Josef (advisor)
This diploma thesis deals with the study of the anticoagulant and antimicrobial agent TauroLockTM, which is manufactured by the german company TauroPharm GmbH. Based on the background research and taking into account the equipment of analytical laboratories of the Institute of Chemistry and Technology of Environmental Protection, optimal methods of analysis were proposed and a series of experiments were carried out which focused on the determination of the active substance and degradation products of taurolidine in TauroLockTM which was stored for a certain period of time in real conditions. The main task of this work was to determine the presence of taurolidine as the active substance and formaldehyde as the undesirable product of its decomposition.
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Hormones in sewage sludge
Jagošová, Klára ; Vávrová, Milada (referee) ; Čáslavský, Josef (advisor)
Currently there is a spate of interest in the presence of pharmacologically active substances in the environment. These substances are excreted in active or metabolized form and with wastewater pass the wastewater treatment plant. Current treatment technologies do not always eliminate all pharmaceuticals effectively and therefore they enter the environment. One of these active groups is the group of steroid hormones. Steroid hormones belong to the group of endocrine disruptors and they are considered to be dangerous for the ecosystems. Due to the hydrophobic character of steroid hormones they undergo partial or total sorption from wastewater to sludge. Sewage sludge is the by product of wastewater treatment and contains heavy metals, organic contaminants and pathogenic bacteria. A part of produced sewage sludge is used as a fertilizer in the Czech Republic. This issue follows the regulation 347/2016 – conditions of agricultural use of sewage sludge. Waste policy of EU will alter the conditions of sludge disposal, so it is necessary to obtain data about the concentration levels, fate and behaviour of those pollutants. This thesis was focused on five natural female hormones and four synthetic, which are used as a part of contraceptive pills and substitutional hormonal therapy. Determination of hormones was performed in four steps including ultrasonic assisted extraction, clean up by solid phase extraction, derivatization and final analysis by gas chromatography with mass spectrometry on triple quadrupole in MS/MS mode.
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