The subject of diploma thesis is to gather knowledge in the production and use of hydrogen. This work is devoted to a comparison of the previously existing processes for producing hydrogen, where the vast majority is filled of fossil fuel. Another section is devoted to new materials for the study based on a number of selected patents and the experiment promising new method for decomposition of water. Based on available data will be carried out energy balance and consequently will be drafted energy system using hydrogen as fuel. In conclusion will be future possibilities evaluated in the field of hydrogen energy.

Thesis on Electron beam welding of ODS materials is divided into theoretical and experimental part. In the first part the theoretical research work focuses on the accurate description of the candidate materials in a research fusion reactor ITER. Following are detailed constructional ODS materials and tungsten alloy as a material of the first wall. The second part of the theoretical research deals with various possibilities of joining high-melting dissimilar materials such as brazing or electron beam welding as well, which will be established in the experimental section. The experimental part of the thesis deals with a joining ODS steel MA 956 with sintered carbide WC-Co and ODS tungsten. These materials are welded by electron beam. Individual samples are distinguished used filler material, preheating or welding parameters. This thesis contains photographic documentations of microstructure the welding samples, results from scanning electron microscopy, and measurements of microhardness across the weld metal.

Divertors are in-vessel, plasma-facing, components in magnetic-confinement fusion reactors. Their main function is to remove the fusion reaction ash (α-particles), unburned fuel, and eroded particles from the reactor, which adversely affect the quality of the plasma. A significant fraction (~15 %) of the total fusion thermal power is removed by the divertor coolant and must, therefore, be recovered at elevated temperature in order to enhance the overall thermal efficiency. Helium is the leading coolant because of its high thermal conductivity, material compatibility, and suitability as a working fluid for power conversion systems using a closed high temperature Brayton cycle. Peak surface heat fluxes on the order of 10 MW/m^2 are anticipated with surface temperatures in the region of 1,200°C to 1,500°C. Recently, several helium-cooled divertor designs have been proposed, including a modular T-tube design and a modular finger configuration with jet impingement cooling from perforated end caps. Design calculations performed using the FLUENT® CFD software package have shown that these designs can accommodate a peak heat load of 10 MW/m^2. Extremely high heat transfer coefficients (~50,000 W/(m^2 K)) were predicted by these calculations. Since these values of heat transfer coefficient are considered to be outside of the experience base for gas-cooled systems, an experimental investigation has been undertaken to validate the results of the numerical simulations. Attention has been focused on the thermal performance of the T-tube and the finger divertor designs. Experimental and numerical investigations have been performed to support both divertor geometries. Excellent agreement has been obtained between the experimental data and model predictions, thereby confirming the predicted performance of the leading helium-cooled divertor designs for near- and long-term magnetic fusion reactor designs. The results of this investigation provide confidence in the ability of state-of-the-art CFD codes to model gas-cooled high heat flux plasma-facing components such as divertors.