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This thesis is focused on the study of the influence of plasma activation of powder ceramic materials on sintered microstructure. In this experiment Diffuse Coplanar Surface Barrier Discharge (DSCBD) device was used for plasma treatment and two materials were chosen to be investigated – Al2O3 (TAI) and ZrO2 doped with 3 mol % Y2O3 (TZ). Two methods of powders dispergation in suspension were used – ultrasound and ball milling. The effect of using of DCSBD on alumina and zirconia powders was investigated by mercury intrusion porosimetry, dilatometry and by evaluation of final relative densities and grain sizes. Generally, was investigated that plasma surface activation of ceramic particles has measurable influence on the final microstructure. In comparison with the non-plasma treated alumina powders, plasma activated powders disperged with ultrasound and ball milling achieved lower values of grain size at comparable relative densities. In case of zirconia powders was observed that plasma treated powders achieve higher relative densities, if ultrasound was used. On the other hand, plasma treated zirconia powders disperged with ball milling achieve lower relative densities compared with non-plasma treated zirconia powders. Final sintering trajectory of plasma treated TZ powders disperged with ultrasound is comparable to the sintering trajectory of non-plasma treated zirconia powders disperged with ball milling and vice versa. Plasma surface treatment is the way of more ecological friendly preparation of suspension and its stabilization than the conventional stabilization methods using chemical additives.

<p>Metalne nanočestice spadaju u nanomaterijale sa širokim spektrom<br />primena u plazmonici, elektronici, katalizi i biomedicini.<br />Razvijene su brojne metode njihove fabrikacije. U ovoj disertaciji<br />predstavljena je mogućnost sinteze metalnih nanočestica korišćenjem<br />jednog novog metoda, u kojem se koristi granični sloj elektrolita i<br />plazme. Niskotemperaturni joni iz plazme se pomoću električnog polja<br />uvode u elektrolit sa prekursorskim materijalom. Ovako uvedeni joni<br />iniciraju oksido-redukcione reakcije sa prekursorom metala u<br />nanometarski tankom sloju na površini elektrolita.<br />Razvijen je generator niskotemperaturne plazme baziran na<br />konfiguraciji dielektričnih barijernih pražnjenja. Urađena je njegova<br />karakterizacija i merenje struje formiranih reaktivnih jona. Metod je<br />verifikovan na primeru nanočestica srebra i platine.</p> / <p>Metallic nanoparticles are nanomaterials with wide range of applications in<br />plasmonics, electronics, catalysis and biomedicine. Thus, a number of<br />methods for their fabrication exist. In this dissertation a possibility of<br />synthesis of metallic nanoparticles using а new method, which exploits an<br />interface between plasma and electrolyte. By means of an electric field, lowtemperature<br />ions from plasma are introduced into the electrolyte with<br />precursor material. The ions from plasma start redox reactions with metal<br />precursor ions within a nanometer-thin layer on the surface of the electrolyte.<br />Nonthermal plasma generator based on dielectric barrier discharges was<br />developed and characterized. Currents of generated reactive ions were<br />subsequently measured. The developed method was verified by synthesis of<br />silver and platinum nanoparticles.</p>

Silybin is the main component of silymarin, a standardized extract obtained from the seeds of milk thistle (Silybum marianum). Flavonolignan silybin has antioxidant, hepatoprotective, chemoprotective and antitumor activities. Natural silybin occurs as an approximately equimolar mixture of two diastereoisomers - silybin A and silybin B. Analytical separation of these diastereoisomers is possible but preparative separation is complicated. The biological activity of the silybin A is different from the silybin B. Silybin diastereoisomers are mainly conjugated to glucuronides and sulfates in organism. A mixture of both silybin diasteroisomers is used in the majority of reported biological, chemical and pharmacokinetic studies. For the first time, optically pure silybin A and silybin B were used for pharmacokinetic study in this thesis. The object of this work was determination of the concentration of free and total silybin in rats plasma in relation to time. Theoretical introduction describes the current state of the problem of chemistry, pharmacology and pharmacokinetics of silybin diastereoisomers. Second part is focused on the selection of appropriate analytical column, chromatographic method and suitable procedure for preparation of biological samples for the determination of the silybin...

This thesis deals with the study of turbulence in tokamak plasma and im- provement of an computer model ESEL. The first chapter deals with the theory related to the study of turbulence in the plasma. For the study of these tur- bulences the results of the probe measurements on the ASDEX Upgrade and COMPASS tokamak and model results from a computer model of the turbulent ESEL are used. The second chapter describes the used probes and the third chapter describes the model ESEL. Contribution of the work is mainly in the fourth and fifth chapter, which summarize the results of the comparisons be- tween the experimental data and model ESEL. The sixth chapter summarizes the most important conclusions from these comparisons. Some agreements and discrepancies were shown. One of the main results of the thesis is the impor- tance of one extra term in one governing equation of the ESEL, which means its improvement. However at present the ESEL is still not able to fully describe the tokamak plasma boundary. 1

This diploma thesis builds on my bachelor thesis, which was focused on the application of low-pressure hydrogen plasma and argon-hydrogen plasma on layers of corrosion products. According to results of the experiments, an appropriate temperature for plasma chemical treatment of lead samples was detected. However, the process of corrosion removal through plasma chemical treatment needs to be further optimized to prevent potential damage to the original historical artefacts. Optimization of the treatment process is therefore the main subject of this work’s research. The model samples with artificial corrosion layers with dual composition were prepared. These samples were put to desiccator with sand and organic acid. The samples corroded in environment of acetic acid or formic acid with the aim of creating the corrosion, which would be at least partially simulated with corrosion on the original artefacts. The process of corrosion lasted for eleven months. After that, the samples were dried out under reduced pressure, put to the protecting foil with humid and oxygen absorbers. In contrast with my bachelor thesis where the continuous regime was chosen for the treatment, the pulse regime with three different condition settings is used. Process of experiment was monitored by OES, surface of samples was analyzed by SEM, EDX, XRD methods. Results from experiments with model samples were used for treatment of original artefacts with missing documentation, so their eventual damaging was acceptable.

Į kieto kūno paviršių krentant jonų srautui, jo paviršiuje vyksta procesai, keičiantys medžiagos elementinę sudėtį. Todėl medžiagos paviršiuje susidaro pakeistasis sluoksnis, kuris gali turėti didelę įtaką paviršiaus erozijai. Pavyzdžiui, termobranduolinės energetikos srityje, tokių elementų kaip volframas, anglis ir berilis maišymasis yra svarbūs procesai įtakojantys pirmosios sienelės eroziją, vandenilio išlaikymą ir prasiskverbimą su plazma sąveikaujančioje medžiagoje bei pirmosios sienelės degradaciją. Fizikiniai procesai sukeliantys šiuos pokyčius nėra pilnai suprasti. Darbe pristatomas fenomenologinis plazmos sąveikos su pirmąją sienele modelis. Modelyje atsižvelgiama į keletą galimų vienalaikių plazmos – paviršiaus sąveikos procesų: joninį dulkėjimą, dalelių iš plazmos adsorbciją ant paviršiaus, nudulkėjusių dalelių resorbciją, terminę difuziją, plazmos dalelių implantaciją sienelėje ir jų sukeltą kaskadinį maišymąsi. Taip pat į modelį yra įtraukta pasirinkta cheminė reakcija. Pateikiami modelio taikymo mažų energijų vandenilio plazmos su 0,1 ir 0,8% anglies priemaišų sąveikos su volframo sienele skaičiavimams rezultatai. Gauti modeliavimo rezultatai yra palyginami su eksperimentų duomenimis. Skaičiavimų rezultatai parodo kaskadinio maišymosi svarbą anglies atomų pernašai taikinyje. / If a material is subjected to an ion flux, atomic composition of the material surface layer (first wall) can be modified by various plasma – first wall interaction processes. Therefore, a modified surface layer of the material is formed due to the plasma – first wall interaction. Effects of mixed materials can be a serious concern for the surface erosion. E.g., mixing of materials such as tungsten, carbon and beryllium in the fusion devices can influence important wall parameters such as a wall life time and hydrogen retention and permeation. Physical processes, which cause this modification, are not completely understood. A phenomenological model of plasma – first wall interaction is presented in the paper. Several possible simultaneous processes of plasma – first wall interaction are considered in the model: ion sputtering, adsorption of plasma particles on the surface, resorption of sputtered particles, thermal diffusion, implantation of plasma particles into the wall and cascade mixing. Selected chemical reaction is included in the model as well. Results of the simulation of low energy hydrogen plasma with 0.1% and 0.8% of carbon impurities interaction with tungsten surface are presented. Obtained results of the simulation are compared to the experimental results. Results of the calculation show importance of cascade mixing to the transport of carbon atoms in the target.

Objective of this diploma thesis was to evaluate internal environment of racehorses according to physical load. Experiment was done on ten english thoroughbred horses. These horses were prepared in training for the plain racing. Blood collections for analysis were done at rest, 5 and 10 minutes after physical load. Analysis were done by metabolic profile test. Biochemical and hematologic measurements were studied on horses. All horses showed high values of selen, from 278,62 to 337,48 umol/l. Thanks to biochemical measurements, at creatine kinases, the biggest value that was find out was 8,13 ukat/l at rest, after 5 minutes of rest, it was in range of 3,72 - 8,23 ukat/l and after 30 minutes, in range between 3,01 - 12,88 ukat/l. At rest the lactate was established at biggest value 6,58 mmol/l, after 5 minutes of rest values on all tested horses increased to biggest measured value 8,98 mmol/l. Factor LDH has increased too, after 5 minutes of rest it has increased from the standing point to the biggest measured value at 9,97 ukat/l. Intensive training of race horses causes that the tracked measurements arent going back to the optimal values after the 30 minute rest. Majority of tracked measurements, especially biochemical, exceeds upper minimum of reference values. We conclude that it would be appropriate adjusting the reference values and standards for english thoroughbred in physical load.

Water pollution by organic contaminants and other anthropogenic substances is one of the major global problems nowadays. The aquatic contaminants include pesticides, pharmaceuticals and personal care products (PPCPs), steroid hormones and synthetic dyes. Traditional processes such as UV irradiation at disinfection doses, coagulation, flocculation, precipitation, microfiltration and ultrafiltration are ineffective for the complete removal of organic contaminants in water, whereas the so called advanced oxidation processes (AOPs) are very effective in the oxidation of numerous organic compounds. The most widely used AOPs include heterogeneous photocatalysis based on near UV or solar visible irradiation, electrolysis, the Fenton's reaction, ozonation, ultrasound and wet air oxidation. AOPs are based on the generation of highly reactive hydroxyl radicals (oOH), which will attack the organic pollutants. However, the lifetimes of these radicals are so short to utilize them effectively. Therefore, the direct radical generations by non-thermal plasmas are widely researched. Three different types of plasma discharges (Dielectric Barrier Discharge, DBD, Gliding Arc Discharge, GAD, and Electrohydraulic Spark Discharge, ESD) were applied to investigate the degradation kinetics of the target pollutants in water. Firstly, the degradation of atrazine, verapamil and hydrocortisone was conducted successfully in the DBD reactor. After 90 min DBD treatment all the target pollutants were almost completely removed. Presence of the intermediates was confirmed by HPLC/UV analysis. The efficiency of dielectric barrier discharge on the degradation of atrazine and hydrocortisone was investigated. Atrazine was almost completely degraded after 90 min DBD treatment. The rate constant of this process was 0.029 min-1 and the corresponding half-life time was 24 min. After 90 min treatment time 54% of the atrazine was converted to CO2. Hydrocortisone was also completely degraded after 90 min DBD treatment. The rate constant of this process was 0.050 min-1 and the corresponding half-life time was 14 min. After five hours of treatment 21% of the hydrocortisone was converted to CO2. Structure of the intermediates was identified by HPLC/MS analysis. Plausible mechanisms for the degradation of target pollutants were also proposed. Degradation kinetics and degradation mechanism of verapamil in water under GAD was investigated. In the final part, the degradation kinetics of verapamil and atrazine by using electrohydraulic spark discharge and ozonation was investigated. During spark discharge, 87% of verapamil and 83% of atrazine were degraded within 40 min. The rate constants of the degradation processes were 0.065 min-1 and 0.094 min-1 for verapamil and atrazine respectively. The power introduced in the discharge was 60 W and is very low compared to the power of GAD. As a result, relatively high energy yields 5.1 × 10-2 g/kWh and 2.3 × 10-2 g/kWh were achieved for verapamil and atrazine respectively. Verapamil was completely removed by ozonation within 1.5 min., while atrazine was almost completely removed within 4 min. The rate constants of the degradation processes were 2.56 min-1 and 0.769 min-1 for verapamil and atrazine respectively. The power applied during ozonation was very low (20 W), compared to plasma discharges, leading to high energy yields 9.4 g/kWh and 1.6 g/kWh for verapamil and atrazine respectively. The degradation kinetics of verapamil and atrazine in water under DBD, GAD, ESD and ozonation were compared. The shortest half-lives of verapamil and atrazine were observed during ozonation. So, we can say that among our AOP systems, ozonation is the most efficient in degrading verapamil and atrazine in water.

Aim of diploma work is research of plasma influence on seed germination in some plant species (wheat and oat). The complex work includes parts both physical-technological and biological. The work discusses a selection of useful seeds for the plasma treatment and describes parameters of plasma processing. It discusses results of germination testing and early growth of seedlings. Parts of the work are electron microscopy output, data processing result, and appendix.