The presented dissertation thesis deals with the use of UV-photochemical generation of volatile compounds (UV-PVG) as a derivatization technique for the combination of high-performance liquid chromatography (HPLC) and atomic absorption spectrometry (AAS) detection. Two model elements arsenic and mercury and their compounds were selected for the speciation analysis. The work was divided into several parts that follow. In the first part of the research, the apparatus for the UV-photochemical generation of the volatile mercury compounds and their detection with a new continuum source and high-resolution atomic absorption spectrometer (HR-CS AAS) with an externally heated detection tube was constructed. The analytical method was adapted for use with atomic fluorescence detection with the aim to improve sensitivity of the determination. Furthermore, apparatus for the electrochemical generation of cold mercury vapor with AAS detection was built. The construction of the apparatus was followed by optimization of the reaction conditions (concentration and flow of electrochemical reagents: sulfuric and hydrochloric acid, mobile phase, carrier medium, flow rate of the carrier gas and localization of its introduction), determination of the analytical figures of merit, and comparation of the methods. Both...

Anaerobic membrane bioreactors (AnMBR) have been established as an efficient method of wastewater treatment to obtain high-quality effluent with low energy consumption. However, membrane fouling leading to flux reduction and an increase in operational costs can negate potential benefits associated with AnMBR. Today’s conventional membrane cleaning process includes physical and chemical approaches, both of which have their own drawback. For this reason, the biological approach was proposed as an alternative to dangerous, energy-consuming, and environmentally unsafe treatment techniques. The combination of UV-C and bacteriophage offers an alternative chemical-free approach for biofouling control. This dissertation aims to test the different order of using UV-C and bacteriophage to clean anaerobic membrane. This dissertation also demonstrates a proof-of-concept to achieve semi-online cleaning using UV-C and bacteriophage, thus increasing the feasibility of described technology. As a result of this work, it was shown that preliminary UV exposure enhances bacteriophage propagation into thick biofilms, and that the bacteriophages are able to affect total cell number and extracellular polymeric substances (EPS) compared to the control. Compared to the control, the semi-online cleaning strategy also resulted in a membrane that took a longer time for the transmembrane pressure to increase in the next operation cycle after cleaning.

Zinc oxide nanoparticles are highly variable materials capable of producing positive and negative responses to their effects on plants. Negative effects are often associated with their excessive concentration, which can cause oxidative stress in plants.Conversely, suitable dosages lead to positive manifestations of growth and improvement in the properties studied. ZnO nanoparticles provide plants with a more acceptable form of zinc that is well accessible and easier to use. However, information about their pos-sible toxic effect in combination with another stress factor is lack. The aim of this work was to compare and evaluate the effects of zinc in the form of nanoparticles (ZnO NPs) with the effects of zinc bound in chelate bonding (Zn-EDTA), in combination with UV-C stress factor in plants Solanum lycoperscicum L. Results of this pilot experiment show that both ZnO and Zn-EDTA nanoparticles of 10.95 mg Zn2+ /l in combination with UV-C radiation have a negative effect on vitality and induce oxidative stress in treated plants. The decisive effect on the toxic effect was based on the concentration used and the form of zinc applied. Differences were expres-sed in expression levels of genes affected by oxidative stress. The results obtained from the expression analysis of the genes made it possible to observe the individual transcripts used to respond to oxidative stress and also to provide information on the possible sy-nergistic effect of UV-C radiation and zinc in both studied forms (Zn-EDTA and ZnO NPs).

This diploma thesis is divided into two parts. In the first, literary one, a basic overview of materials, the reasons for use of surface treatment and its impact on the environment is mentioned. Also, the thesis contains a vast chapter on paints. In the second, exprimental part, the thesis deals with properties of three considered UV cured paints applied on two underlying materials, one of which was inert (plate glass) and the second one was a veneered component (chipboard, 8 mm thickness + venner of spruce, cherry tree and walnut tree). The paints mentioned were applied on the underlying material by glass rod and plastic spatula. Then they were cured within UV tunnel, manufactured by a company called FUSION. The curing took place under two different conditions, which had significant influence on the final properties - those conditions were different settings of transportation belt speed in the tunnel and different average intensity of the quicksilver lamps. Properties and endurance of these paints were verified by four selected tests. First of them verified hardness of the finished surface in accordance to methodology of determination of coat hardness by pendulum impact testing machine, which is based on standard ČSN 67 3076, the second test verified coats´ grinding ability using device Erichsen 255. Another test verified so-called chemical resistances of the finished surface according to standard ČSN EN 12 720: Assessment of surface resistance to cold liquids. Verifying of assessed paints´ mechanical endurance was integral to this thesis´ experimental part, where verifying of coat´s resistence to the abrasion in accordance to standard ČSN 91 0276 was chosen. Afterwards, on the basis of the knowledge gained from the experimental part of the diploma thesis a methodology for verifying of assessed properties of UV curable paints and its utilization in practice was suggested.

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Pesticide testing is of practical interest in various areas of today’s world due to their prevalence and toxicity. These areas include agriculture, environmental, chemical plants, and many others. Herbicides, like Roundup, contain secondary amines such as glyphosate. The ability to detect secondary amines could offer a method for glyphosate detection in agricultural and environmental samples. Secondary amines can interact with metal complexes through electron charge transfer. Such interactions can cause a change in the metal’s electron configuration and energy state and can be seen in the UV-Vis spectrum. Metal phthalocyanines (MPc’s) and other organometallic complexes have been of interest for these reasons and may be applicable to glyphosate detection without extensive laboratory tests. UV-Vis absorption can further provide quantitative measurements. An evaluation of FeTSPc’s ability to aid in remediation via adsorption supports was also examined.

Möjligheten att syntetisera UV-härdande bindemedel från enbart förnyelsebara startmaterial (syra A och alkohol A) eller från kombinationer av dessa med konventionella monomerer (syra B, C och D; alkohol B, C, D, E samt cyklisk ester A) utvärderades. Effekten av två katalysatorer, tenn(II)oktanoat och butyltenn, på direkt förestring och på ringöppning utvärderades. Totalt framställdes 22 polyestrar som analyserades med avseende på syratal, medelmolekylvikt (SEC), kulörindex (Gardner), och strukturell sammansättning (NMR). Bindemedlen formulerades med UV-initiator och härdades med UV-ljus. De torra filmerna utvärderades med avseende på hårdhet (pendelhårdhet), flexibilitet och kemisk resistens.   Det var möjligt att framställa polyestrar baserade på ovan nämnda monomerer. Några monomer gav bäst egenskaper med avseende på pendelhårdhet och flexibilitet medan andra byggstenar resulterade i bättre kemisk resistens.