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The influence of alloying elements n the hardenability of carburization steels
Komoráš, Miroslav ; Helán, Jiří (referee) ; Jan, Vít (advisor)
This bachelor thesis is dealing with material analysis of cams used in radial hydraulic motors. The goal of this bachelor thesis is to identify root causes for not proper quenching of some parts made of material 34Cr4 by using microstructure analysis and hardness measurement. Theoretical part of thesis looks into influence of alloying particles on quenchability of carburizing steels, methods of heat treatment and carburizing. Experimental part follows up microstructure analysis and case depth hardness of analysed samples.
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Heat treatement of tool steels
Kubín, Matěj ; Moravčík, Igor (referee) ; Jan, Vít (advisor)
This thesis deals with heat treatment of tool steels. The work is divided into two parts. The theoretical part includes marking, properties and theoretical processing of tool steels. It also contains the technique which is used for sample preparation. In the experimental part there is an examination of the two common sold drills. Samples were made from the drill, on which metallographic analysis and heat treatment was performed.
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Composite Dental Biomaterials - Structure, Analysis and Properties
Matoušek, Aleš ; Vaněk,, Jiří (referee) ; Lapčík,, Lubomír (referee) ; Cihlář, Jaroslav (advisor)
The aim of this work is to define relations between grain size and bioaktivity of oxide ceramics, specifically ZrO2, Al2O3 and HA. Ceramic materials with grain size from 100 nm up to 10 m, with various surface roughness, were tested for its bioactivity. Ceramography analysis was performed for all tested materials to precisely describe microstructures. Biological properties of the ceramic materials were tested via dilation tests directly in-vitro and by in-vitro extraction. Three cell culturing lines: osteoblast MG63, fibroblast L929, and epithelioid HeLa, were used for our testing. An influence of the grain size on the biological response was only found for the ceramic materials which had been thermally etched. The thermally etched nanocrystalline samples had larger areas covered by cells than ceramics with coarse grain microstructure. Biological tests on layered composites Al2O3×ZrO2 showed the cell selection determined by the type of material, where ZrO2 surfaces were preferably covered. Improved biological response of nanocrystalline ZrO2 was demonstrated on ceramic ZrO2, Al2O3 and SiO2 substrates with nanocrystalline coating of ZrO2. In this work a novel technological process for the formation of defect-free coatings was developed. Sintered coatings were tested using in-vitro technique with cell line HeLa, L929 and MG63 for up to 72 hours. The results of the biological tests of nanocrystalline coatings were consistent with results from the bulk nanocrystalline thermally etched ZrO2 ceramics.
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Light microscopy and its applications
Pokorný, Pavel ; Prochazka, David (referee) ; Lošťák, Martin (advisor)
This bachelor´s thesis describes problems of light microscopy for readers. Part of this bachelor´s thesis is dedicated to basic terms of the light microscopy. Next chapters are dedicated to observing techniques - brightfield illumination, darkfield illumination, oblique illumination, Rheinberg illumination, phase contrast, differential interference contrast, polarized light microscopy and fluorescence illumination.
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Microscopy 2008
Hozák, Pavel
Two-day conference responding to novel trends in light and electron microscopy and their impact on researchers in the Czech Republic and Slovakia. Contributions were presented in biomedical as well as physics and material science fields. The Conference was held in a sports area in the heart of the Czech-Moravian Heights and was closed by an opulent rout with wine degustation.
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