This diploma thesis deals with the study of inkjet print degradation on handmade paper modified by polymer layer containing light stabilizers and inorganic filler. The polymer layer coated on the medium consisted of polyvinylalcohol, titanium dioxide and light stabilizer. The influence of light promoted degradation and light stabilizers was observed. The experiments were carried out on Q-SUN Xenon Test Chamber device, Model Xe-1-B/S. Colorimetric values of test chart were measured and the influence of different light stabilizers on the color difference between original and faded sample was evaluated.

This diploma thesis focuses on the photocatalytic effect of titanium dioxide and ultraviolet light. Theoretical part shows the effect of titanium dioxide and aplication in various branches. Antibacterial effect of titanium dioxide iluminated by ultraviolet light was observed in the flow tube reactor on the yeast Hansenula anomala. After adjusting the optimal flow rate experimented with different inicial concentration of yeast cells. To increase desired effect also silver was used in the photocatalytic system. As observed in many previous studies, silver decreases the time needed for killing the microorganisms. The optained date were analysed.

In this diploma thesis, photocatalytic effect of titanium dioxide with addition of silver was described and demonstrated on inactivation of the yeast Candida vini. Titanium dioxide was prepared by sol-gel process and deposited by printing metod on soda-lime glasses. On the deposit of titanium dioxide was added silver in various concentrations which increased effect of TiO2. Inactivation of yeasts was examined by effectiveness of UV light with intensity 170 and 100 W/m2.

Heterogenous photocatalysis using titanium dioxide seems to be a promising method for disposal xenobiotics from the environment. The aim of this diploma thesis is the study of degradation of selected xenobiotics and biologically active substrances applying this method. Theoretical part of diploma thesis deals with the principals of heterogenous photocatalysis by means of a semiconductor TiO2 and the examples of its possible application are mentioned too. The compounds which could be appropriate for a study of degradation were selected from the group of pharmaceuticals and pesticides. The properties of target substances and their environmental impact were described. Furthermore, a bibliographic search focused on the possibilities of their analytical determination was conducted. The experimental part of the thesis describes the experiments with photocatalyst in a form of powder as well as with immobilized photocatalyst in thin layer on a carrier. Identification and quantification of analytes was realized by high performance liquid chromatography with mass spectrometic detection.

The diploma thesis describes monitoring of photocatalytic activity of titanium dioxide thin films and photocatalytic degradation of azo dyes, the degradation was also experimentally researched in thin film with polymer matrix. Suitable dye for construction of optical sensor for UV light was chosen from the rate of the azo dyes fading by UV and VIS light. The bleaching rate of the sensors was influenced by addition of another dye into the composition and also by concentration of photocatalyst, polymer and calibration agents. At the end of this thesis, the reciprocity test of prepared compositions was made.

Tato diplomová práce se zabývá testováním vhodných indikátorových inkoustů k ohodnocení fotokatalytické aktivity. V teoretické části jsem studovala literaturu související s možnostmi stanovování fotokatalytické aktivity a zaměřila se také na kinetiku, kterou je zmíněnou fotokatalýzu možné ohodnotit. V experimentální části jsem mnou vybraná barviva natiskla na skleněný substrát obsahující vrstvu oxidu titaničitého a následně je otestovala. Došlo také k úpravě aparatury, aby bylo možné měřit větší škálu barev. Po otestování a vybrání vhodných barviv jsem se pokusila o optimalizaci podmínek tisku. Nakonec jsem optimalizovala i samotnou aparaturu.

This thesis deals with the study of cells on nanostructured surfaces of titanium dioxide, which are produced by the electrochemical method called anodic oxidation. The theoretical part is formed by an overview of manufacturing nanostructured surfaces using anodic oxidation method. It mentions the influence of external factors on the geometric parameters of the structure and description of methods of characterization structures. Furthermore there is processed outline of use for biomedical application and the description of interaction of the cell with surface. The practical part includes description of the production of nanoporous and nano-tubular structures made on thin films of titanium by direct method of anodic oxidation on which was studied the influence of external factors. Described a procedure and production of nanorods structures and nanodots generated using alumina template (AAO) which is subsequently carried out the study of the behavior of cells, which includes tests of adhesion, examination of morphology of cells, assays of proliferation and differentiation. Structures are under investigation of the interaction of cells with the nanostructured layer compared with the smooth surface of the titanium dioxide.

The subject of this theses is a preparation of chemical UV dosimeters working on diverse principles and their printing. Three UV dosimeters were prepared. The first one is based on a photocalalytic reaction of titanium dioxide with redox dyes. Two other dosimeters are based on a reaction of a photolabile substance able to produce an intermediate reacting with a dye. Prepared dosimeter compositions were coated using a material roll-to-roll printing machine on a corona-treated PET foil. Prepared dosimeter compositions were calibrated for desired exposition to UV radiation doses. Validity of a reciprocity law was verified.

This diploma thesis deals with changing properties of the thin layered titanium dioxide dispersion depending on the time of ball-milling. Titanium dioxide is immobilized on glass or conductive glass using the spin-coating method and the prepared thin layers are then characterized by various analytical methods. All of used analytical methods are described in theoretical and experimental sections, these methods include scanning electron microscopy, profilometry, dynamic light scattering, integrating sphere, ellipsometry, BET isotherm, voltammetry and chronoamperometry. At the summary of this diploma thesis is described how the properties of titanium dioxide thin layers change during ball-milling process.

Le dioxyde de titane suscite un grand intérêt dans le domaine de la photocatalyse. Cependant, il n'utilise que la composante UV du flux solaire soit 4-5 % de l'énergie disponible. Un objectif de cette thèse est d'élaborer un matériau capable d'absorber dans le visible tout en restant actif sous lumière UV. Des nanoparticules de dioxyde de titane modifiées avec de l'or et/ou de l'azote ont été synthétisées par pyrolyse laser. Les poudres obtenues ont été caractérisées systématiquement par différentes techniques physico-chimiques (analyse ICP-AES), structurales (DRX), morphologiques et texturales (MET, MEB, BET), optiques (Spectroscopie UV-Visible) et électroniques (XPS, RPE et TRMC). Les particules présentent une structure cristalline majoritairement anatase, avec une taille moyenne de l'ordre de 7-10 nm. Leur efficacité photocatalytique a été évaluée par HPLC vis-à-vis de la dégradation d'acides carboxyliques (C1-C4) sous lumière UV et Visible. Les résultats photocatalytiques obtenus sur un polluant modèle (l'acide formique) ont révélé que sous UV le TiO2 préparé par pyrolyse laser est nettement plus actif que la référence commerciale. La modification à l'or améliore encore l'efficacité en facilitant le transfert de charge, alors que le dopage à l'azote introduit des sites de recombinaison provoquant donc un effet négatif. Ces résultats ont été corrélés à la dynamique des porteurs de charge étudiée par TRMC (Time Resolved Microwave Conductivity). La combinaison des deux élèments Au et N montre une efficacité proche de la référence commerciale, tout en introduisant une activité dans le visible. Dans le cas des acides à plus longue chaîne, la photoactivité des différents photocatalyseurs est proche de la référence commerciale sous lumière UV, mais reste très limitée dans le visible. La compréhension des mécanismes de dégradation a été abordée par la Résonance Paramagnétique Electronique (RPE). / Titanium dioxide is the most widely used photocatalyst due to its amazing properties. However, TiO2 is activated by UV radiation which represent about 4-5 % of solar light. One aim of this work is to shift the adsorption of TiO2 to the visible range while maintaining photoactivity under UV. Therefore N-doped and gold modified TiO2 nanoparticles have been synthesized in one step by laser pyrolysis. The materials have been characterized; their photocatalytic activity was evaluated by the degradation of carboxylic acids (C1-C4) under both UV and Visible irradiation. When dealing with the decomposition of formic acid under UV light, all samples exhibit a higher activity compared to commercial P25. Modification with Au increases the reaction rate by enhancing charge separation, while N-doped sample are less efficient due to recombination centers induced by Nitrogen. These results were correlated to the dynamic of electron/hole pairs studied by TRMC (Time Resolved Microwave Conductivity). Moreover, the combination of Au and N showed an efficiency similar to commercial P25 under UV irradiation associated to photoactivity in the visible range. In the case of C2-C4 acids, photocatalytic performances of all photocatalysts are similar to commercial P25 under UV, but very weak under visible light. Degradation mechanisms were investigated by ESR (Electron Spin Resonance).