Zinc is widely used as an alternative to antibiotic in piglets. Recent studies demonstrated the antibacterial effect of zinc nanoparticles. It is believed that zinc nanoparticles will exhibit better antibiotic effects than previously used medication zinc. There is a need to define ZnNPs effect on the organism. This thesis compares the influence of administration of zinc oxide nanoparticles and zinc standard forms at the dose of 2000 mg/Zn/kg diet in rat organism. The antioxidant status of rats and toxicity of zinc and zinc nanoparticles were monitored. The level of accumulated zinc for blood was on average 12 mg / kg ± 6 mg / kg, for liver 74 mg / kg ± 50 mg / kg, for kidneys 37 mg / kg ± 30 mg / kg for both nanoparticles and normal zinc . ZnNPs and zinc oxide did not extremely influence antioxidant status of samples of blood, liver and kidney. A significant effect was observed with GSH levels. Histological study of liver and duodenum showed slight tissue damage after administration of both zinc and nanoparticles. Zinc nanoparticles demonstrated beneficial effects as well as standard form.

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Thesis is focused on verification of suitability of Laser-TIG technology for penetrating welding of galvanized sheets, made of WSS M1A 365-A14 50G steel and DC01 steel. Electric arc functions here as a preheating for evaporation of zink layer. Electric current was chosen as a variable parameter of magnitudes 0, 20, 30 and 40 A. Test welds were made, which have been subjected to a tensile test and metallographic evaluation. The positive influence for electrolytically galvanized steel WSS M1A 365-A14 50G was registered and determination of optimal welding parameters was successful. The electric arc also had a positive effect on welding of hot-dip galvanized steel DC01, but at the selected test parameters not enough to achieve a reliable connection.