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Analysis of the life service of PVC roofing foils
Rosecký, Pavel ; Žák,, Antonín (referee) ; Žižková, Nikol (advisor)
Roofing foils are known for several years as building material for roof hydro insulation but their life service is not yet fully known. This thesis is focused on problematics of life service of roofing foils. In theoretical part there is discribed structure of foils and impacts which assist degradation processes. Practical part modifies the methodology artificial aging which is simulated in QUV tester and Q-SUN XE3 tester lumber-rooms. The thesis is trying reach with the results to natural aging as close as possible. The testing captures attributes which are more prone to degradation.
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Photochemical generation of volatile species of cobalt for analytical atomic spectrometry
Vyhnanovský, Jaromír ; Musil, Stanislav (advisor) ; Nováková, Eliška (referee)
This master's thesis deals with the optimization of conditions for photochemical generation of volatile species of cobalt. Volatile species of cobalt were generated in a flow injection system using a high-efficiency flow through UV generator from formic acid based medium. For detection a high-resolution continuum source atomic absorption spectrometer was used. The volatile species were atomized using a diffusion flame atomizer because of its high robustness. First the optimizations of the parameters affecting the atomization in the diffusion flame and the parameters affecting the transport of the volatile species from the UV generator into the atomizer were carried out (flow rates and composition of the gases, type of a separator, observation height). After that, the optimization of the parameters of the photochemical generation itself was carried out. These were the composition of a reaction medium (concentration of formic acid and formate, type of formate salt) and irradiation time. The possibility of generation of the volatile species from acetic acid based medium was also investigated, but no signal was observed. At chosen optimal conditions of generation the influence of potential interferents was examined, mainly from inorganic acids (HNO3 and HCl) and some transition metals (Fe, Cu and Ni)....
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Optimization of methods for determining the durability of wood coating systems
Škvařil, Michael ; Žák, Antonín (referee) ; Vaněrek, Jan (advisor)
The bachelor thesis deals with the optimization of methods for determining the durability of wood coating systems. The theoretical part deals with a detailed analysis of wood coating systems, including the specification of their composition, especially with a focus on modern water-borne coating systems. In the practical part an experiment was carried out, where on the selected types of coatings applied to lumber was performed analysis of selected durability parameters of coatings after exposure to short-term and long-term exposure to degradation factors
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Design and Operation of Water Disinfections Plants
Krupicová, Simona ; Rajnochová, Markéta (referee) ; Kučera, Tomáš (advisor)
In the first part of my bachelor thesis I deal with individual disinfectants used for hygienic supply of drinking water based on chlorine and without chlorine. Then I mention the operation without chlorine disinfectants. In the second part of this thesis I describe individual plants using various disinfection methods and at the end of the thesis I compare these methods and use it in practice.
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Photosensitive thin polymeric layers
Rudická, Andrea ; Klusoň, Petr (referee) ; Veselý, Michal (advisor)
This bachelor thesis deals with photosensitive thin polymeric layers. The experimental part deals with the composition preparation and layers coating. The prepared layers were exposed and studied in detail for their color response to the light. The aim was to prepare a dosimeter, to achieve significant color change between individual doses, to improve the mechanical resistence of the layers and to adjust the sensitivity of the compositions to UVB radiation.
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Simple Electrochemical DNA Biosensor for Detection of DNA Damage Caused by UV Radiation
Arustamian, Daria ; Vyskočil, Vlastimil (advisor) ; Dejmková, Hana (referee)
Ultraviolet (UV) radiation is a common DNA damaging agent. Major DNA lesions, such as cyclobutane pyrimidine dimers (CPDs) and pyrimidine-(6-4)-pyrimidone (6-4PPs) photoproducts, are carcinogenic and mutagenic. UV induced DNA damage was investigated using a simple electrochemical DNA biosensor based on an ultra-trace graphite electrode (UTGE) and low molecular weight doble-stranded DNA (dsDNA) from salmon sperm. Biosensor was prepared using adsorption of dsDNA on a surface of the UTGE and then used to detect UV-induced DNA damage. Effects of UV radiation were investigated using a combination of several electrochemical technics: square-wave voltammetry (SWV) for direct monitoring of DNA base oxidation and cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), as non-direct methods, using redox-active indicator [Fe(CN)6]4-/3- . CV and EIS, which allow characterization of electrode surface, were used to optimize preparation of the dsDNA/UTGE biosensor. Prepared dsDNA/UTGE biosensor was exposed to UV radiation using UV lamp with two set wavelengths: UVC of 254 nm and UVA of 365 nm. UVC radiation was used to damage DNA. Relative signal decrease was 50% after 20 minutes of exposure to UVC radiation. UVA radiation was used to compare effects of different types of UV radiation. Obtained...
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Generation of ozone by photochemical processes in CO2
Kucserová, Aneta ; Salyk, Ota (referee) ; Mazánková, Věra (advisor)
The bachelor thesis deals with the measurement of ozone concentration, which was produced by dielectric barrier discharge, corona discharge and UV lamp. The concentration of ozone in the air was also measured. The theoretical part deals with the basic properties of ozone, its use and determination of concentration by various methods. In the experimental part, ozone generation is described by the above-mentioned discharges.
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Svetlostálosť morených povrchových úprav
Machunková, Andrea
This bachelor thesis deals with the influence of artificial UV radiation on plywood samples made of chosen woods - oak (Quercus), alder (Almus) and ash (Fraxinus) and examines the influence of surface conditioning on light permanency of wood surface. Samples were stained by water-soluble and solvent stains and finished by water-soluble and solvent lacquers. Samples were examined by standardized tests in the laboratory. We have determined the influence of type of stains on the speed of drying times and hardness and roughness of the coatings and evaluated changes in color depending on the surface conditioning.
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Study of properties of Fiber-Reinforced Polymers
Fojtášek, Martin ; Hela, Rudolf (referee) ; Bodnárová, Lenka (advisor)
Bachelor thesis deals with monitoring the properties of the FRP reinforcement when exposed to aggressive environments that cause degradation. In the theoretical part of this thesis there are described the method of production, the most commonly used types of FRP profiles, the composition of the FRP profiles, durability of FRP profiles against the action of aggressive environment and durability of the FRP material in the damage environment. Further more there are briefly described the most common types of tests on FRP profiles. In the experimental part of this thesis there are defined conditions for laboratory testing of FRP samples, which were stored in an alkaline environment at temperatures of 20 degrees, 40 degrees and 60 degrees. These samples of the FRP were stored and tested after 90 days. Subsequently there are described the changes of the physical properties of rebar in a time when saving in an aggressive environment.
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Mechanisms of DNA repair in the moss Physcomitrella patens
Holá, Marcela ; Angelis, Karel (advisor) ; Bříza, Jindřich (referee) ; Fajkus, Jiří (referee)
Over the course of an organism's life, its genome is exposed to endogenous and exogenous chemical, physical and biological agents - genotoxins. These genotoxins alter its basic structural components - sugar residues, phosphodiester bonds, and nitrogenous bases. Organisms have therefore evolved a plethora of different strategies to both repair DNA lesions and maintain genomic stability. These DNA repair pathways are linked with several other cell pathways, including chromatin remodelling, DNA replication, transcription, cell cycle control, apoptosis - programmed cell death (PCD), thereby providing a coordinated cellular response to DNA damage. Biochemical mechanisms of DNA repair are relatively well understood in yeast and mammals, however, far less so in plants. While these repair mechanisms are evolutionary conserved, significant differences still remain. Therefore, further investigation is required. This thesis summarises the introduction of a novel plant model - the moss, Physcomitrella patens (Physcomitrella). As a haploid gametophyte with unique characteristics of high frequency of homologous recombination (HR), and apical growth of filaments, it is an ideal organism to study DNA repair in plants. Previous research on Physcomitrella regarding mechanisms of DNA lesion repair induced by...
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