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Optimization of hydrogel carrier for assessment of antimicrobial activity of biocidal surfaces
Antálek, Adam ; Jančovičová, Viera (referee) ; Králová, Marcela (advisor)
This diploma thesis deals with the optimization of the composition and properties of hydrogels as carriers of microbial populations for the evaluation of the antimicrobial effects. There are standardized procedures for assessing antimicrobial surfaces, but they have shortcomings, such as the necessity of testing exclusively under laboratory conditions. In the presented work, a new evaluation methodology is proposed, which utilizes a modified resazurin test and hydrogels as platforms for bacterial seeding, enabling the assessment of the investigated antimicrobial surface. The composition and properties of hydrogel carriers were successfully optimized with respect to their swelling and mechanical properties, thereby improving recovery compared to standardized procedures. Tests on antimicrobial materials showed that the bacteria used on hydrogels continued to grow, rendering the use of composite hydrogels for this application impractical.
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Preparation and charakterization of WO3 layers by brick and mortar method
Blecha, Tomáš ; Pekárková, Jana (referee) ; Králová, Marcela (advisor)
This master’s thesis deals with thin films of tungsten trioxide, which are prepared by combining nanoparticles and a binder. The composite consisted of either milled WO3 nanoparticles of different sizes or the combination of milled nanoparticles and dopamine stabilized peroxotungstic acid. The prepared compositions with the addition of templating agent polyethylene glycol were deposited on conductive FTO glass by spin coating method and further used as a photoanode in a photoelectrochemical cell. This work then focuses on studying the influence of the milled particle size and the amount of binder in the composition on the physicochemical properties of WO3 photoanodes in an attempt to measure the highest photocurrrents.
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Photoelectrochemical oxidation of aqueous polutants
Pachovská, Martina ; Králová, Marcela (referee) ; Dzik, Petr (advisor)
The thesis is focused on the use of photochemical reactions and their applications for removal of aqueous pollutants such as organic acids. For evaluation of photochemical oxidation was used benzoic acid as model pollutant. Decreasing of concentration and oxidation products were monitored by UV-VIS spectrometry. The formation of oxidation products was observed by fluorescence measurement. Subsequently the stability and properties of model aqueous pollutant and electrochemical properties of used photoelectric cells were studied. The aim was to determine the appropriate reaction conditions and limits of degradation reaction.
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Self-cleaning Properties of Thin Printed Layers of Titanium Dioxide
Králová, Marcela ; Brezová, Vlasta (referee) ; Krýsa, Josef (referee) ; Veselý, Michal (advisor)
Tenké vrstvy oxidu titaničitého byly imobilizovány na sodnovápenatá skla a skelný uhlík použitím jak techniky materiálového tisku tak metodou chemického napařování. Pro přípravu titaničitých solů byly použity metody sol-gelu a nebo hydrotermální syntézy. Struktura připravených vrstev byla zkoumána rastrovací elektronovou mikroskopií a mikroskopií atomárních sil. Krystalická struktura připravených TiO2 byla analyzovány pomocí XRD metody. Fotoindukováná superhidrofility pripravených vzorků byla charakterizována měřením kontaktních úhlů. Fotokatalytická aktivity připravených vzorků byla testována na fotokatalytické oxidaci 2,6-dichlorindofenolu a kyseliny mravenčí. V případě sol-gel vrstev byl zkoumán vliv množství naneseného TiO2 a množství PEG, který byl do solu přidán jako praskliny potlačující činidlo. V případě hydrotermálních vrstev byl zkoumán vliv času a teploty syntézy a množství vrstev na výslednou účinnost vzorku. U chemicky napařených vzorků byl zjišťován vliv intenzity záření. Byla porovnána fotokatalitická aktivita vrstev připravených materiálovým tiskem a chemickým napařováním a byl vyhodnocen nejaktivnější vzorek.
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Investigation of Methacrylated PVAl Photochemical Crosslinking
Králová, Marcela ; Čeppan, Michal (referee) ; Dzik, Petr (advisor)
This diploma thesis deals with a detailed study of photoinitiated radical polymerization of macromers base on PVAl containing lateral GMA moieties. The main goal is the evaluation of the influence of photoinitiator concentration, polymerisable group content and/or other aditives on the polymerisation rate. Other goals include the study of possible influencing the photochemical speed by lowering the glass transition temperature, compatibility with various photoinitiators etc. Attention is also paid to the study of prepared 3D polymeric networks properties
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Photocatalytic activity of hybrid titanium dioxide layers treated by plasma
Koukolová, Anna ; Králová, Marcela (referee) ; Veselý, Michal (advisor)
The bachelor thesis deals with photocatalytic activity of thin layer of titanium dioxide deposited onto PET flexible foil treated by plasma. Photocatalytic activity is measured by two different methods, degradation of dye Acid Orange 7 and benzoic acid. Possible model compounds for evaluation of photocatalytic activity as well as deposition techniques for preparing thin layers of photocatalyst were discuss in the theoretical part. Changes of photocatalytic activity were found insignificant with plasma treatment. Evaluation used Acid Orange 7 is suitable. Unlike method with benzoic acid was discovered inappropriate for measuring of photocatalytic activity for photocatalyst deposited onto PET foil.
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Outdoor applications of photocatalytic materials
Šimončičová, Monika ; Králová, Marcela (referee) ; Veselý, Michal (advisor)
This bachelor thesis deals with the evaluation and optimization of the method for the determination of photocatalytic activity of facade coating layers with and without photocatalyst admixture titanium dioxide. The layers are tested by the photooxidation of the organic dyes Acid orange 7 and methylene blue, which are model compounds of pollution. Degradation of organic dyes is monitored by UV-VIS spectrophotometry and evaluated by determination of rate constants and specific photoactivity. The aim is to find out which of the facade coating has the highest photoactivity.
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UV dosimeter for safer sunbath
Hinca, Sven Barbara ; Králová, Marcela (referee) ; Veselý, Michal (advisor)
V dnešní době je veřejnost konstantně vystavená slunečímu světlu a tím také UV záření. Protože UV radiace je prokázaným karcinogenem a kvůli rapidnímu zmenšování ozonové vrstvy v nedávné minulosti, monitorování osobního vystavení UV záření, a povědomí o riskantnosti ozáření vyššího než je bezpečná dávka, je důležitější než kdykoliv předtím. Tato práce je zaměřená na vývoj a zjednodušení osobní UV dozimetrie pro použití veřejností tak, aby každý uměl vyhodnotit riskantnost delšího vystavení UV radiaci.
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Hydrogel carriers of microbial cultures for contact sampling of biocidic surfaces
Antálek, Adam ; Králová, Marcela (referee) ; Dzik, Petr (advisor)
This bachelor thesis is focused on the development and optimization of material for biological sampling of active surfaces with biocidal properties. The aim was to modify polyvinyl alcohol with methacrylic groups, to determine the degree of conversion of the prepared polymer, to optimize the preparation of hydrogels. Furthermore, the aim was to investigate the effect of copolymerization aditives of sodium methacrylate and polyethylene glycol dimethacrylate on the swelling and mechanical properties of hydrogels. It was found that 20% vol. the content of polyethylene glycol dimethacrylate most significantly increases the swelling rate in the initial phase of water absorption. The hydrogels of this composition and the hydrogels consisting only of pure methacrylated polyvinyl alcohol, despite the assumption, increase the mechanical resistance after swelling to equilibrium. The hydrogels of the composition containing both copolymer aditives absorb water at equilibrium to the highest extent of the investigated compositions.
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Optimization depozition variables during material printing of titania coatings
Mlčkovová, Hana ; Králová, Marcela (referee) ; Dzik, Petr (advisor)
This thesis studies the effect of conditions in the printing material layers of titanium dioxi-de sol-gel formulations for the print properties of the resulting films – TiO2, which were pre-pared from a precursor of titanium tetraisopropoxide (TTIP). Thin films were deposited on the printing material soda lime glass and the layer thickness was controlled by repeatedly apply-ing. Prepared films were subjected to observation under an optical microscope, and the thic-kness of the layers was measured by mechanical profilometry.
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