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Comparison of different approaches in ab initio modeling of mechanical and magnetic properties of materials
Čavojec, Martin ; Řehák, Petr (referee) ; Zelený, Martin (advisor)
Tato diplomová práce se zabývá zkoumáním vlivu kvantově-mechanického popisu mezi-atomárních interakcí na výsledky ab initio výpočtů magnetických a mechanických vlastností Fe, -TiAl a Ni2MnGa. Zkoumány byly dvě metody pro popis interakcí, jmenovitě metoda projektovaných přidružených vln a metoda lineární kombinace atomových orbitalů, které jsou implementovány v ab initio softwarech VASP a SIESTA. Hodnoty magnetických momentů v závislosti na objemových a tetragonálních deformačních drahách poukazují na relativní srovnatelnost napříč těmito metodami. Avšak výsledky elastických konstant poukazují na nevhodnost ab initio softwaru SIESTA pro výpočet elastických konstant metodou napětí-deformace (stress-strain metoda). Součástí praktické části této diplomové práce je vytvoření skriptu pro výpočet elastických konstant v programovacím jazyku Python.
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Materials for biodegradable bones based on Fe
Hrabovský, Jan ; Vondrák, Jiří (referee) ; Sedlaříková, Marie (advisor)
The thesis deals with biodegradable bone implants which must have good mechanical properties and also good compatibility with the human body. The thesis contains literary research in the area of bone physiology, biogenic materials and implants for the human body. The thesis focues on the selection of suitable materials for biogenic implants. It is also described the preparation of iron powder mixtures and application onto selected materials. The selected samples were subjected to thermal analysis.
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Bone implants based on Fe
Bachmayer, Marek ; Vondrák, Jiří (referee) ; Sedlaříková, Marie (advisor)
This thesis deals with usage of metal materials in bone implats creation process. This work also includes information about structure and attributes of bones, body fluids and content of iron in human organism. Following part of the paper deals with osteosynthesis, therefore commonly used methods of treating bone defects. Next part of this bachelor’s thesis is discussing the issue of biomaterials, biocompatibility and biodegradability of metal materials. Sample preparion procedure and description of samples, electrochemical corrosion and microscopic observation is included altogether with a pictorial documentation at the last chapters of this paper.
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Assesment of Economic Performance of Selected Company
Páleníková, Tereza ; Hanušová, Helena (referee) ; Režňáková, Mária (advisor)
The bachelor´s thesis focuses on the evaluation of the financial situation of the company MR STEEL GROUP, s.r.o. It is based on analysis of the financial statements from the years 2012 – 2016. To determinate the economic performance I have chosen the financial analysis. The thesis contains the theoretical part and the practical part. The practical part contains the introduction of the company, the analysis of the economic performance and the proposals for its improvements. The comparison of the company with the competitors of the same size is also included in the practical part.
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Study of the effect of myocardial fibrosis on elemental distribution in rat soft tissues using Laser Ablation ICP-MS
Machalová, Martina ; Zlámalová Gargošová, Helena (referee) ; Vašinová Galiová, Michaela (advisor)
The most common cause of death in the Czech Republic continue to be cardiovascular diseases. The field of heart failure therapy still keeps moving forward. Yet myocardial fibrosis is one of the consequences and causes of heart failure for which there exists no effective medical care. The solution would be predicting the advancement of fibrosis and a preventive therapy. Many medical methods are being developed now in this regard, and the element distribution in affected tissue could help them. That is the reason why this work centers on the research of the element distribution in rat hearts with an induced myocardial fibrosis. An influence of sample couloration on the analysis was observed during its course. Special attention was paid to the distribution of iron in the fibrotic tissue as well as to the comparisson of the images of myocardial fibrosis. It seems that the iron distribution specificly could be helpful in recognising a damaged myocardium.
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Ellipsometry of Thin Films
Novotný, Zbyněk ; Navrátil, Karel (referee) ; Nebojsa, Alois (advisor)
Diploma thesis deals with ageing process of thin films of Co and Cu on Si substrate, prepared by the IBAD method. The process of film ageing, which depends on time of exposition to the atmosphere at room conditions, was investigated with spectroscopic ellipsometry (VIS+UV) and atomic force microscopy. In case of thin Co films, approximately four days long incubation period was observed. During this time period, a change in the optical parameters of the film occurs without a measurable change of the film topography. Using non-contact atomic force microscopy, a growth of the transitional film in the island growth regime was observed. During the ageing of thin Cu films, two stages of growth of the transitional layer were observed - nucleation stage and growth stage. Both of these time periods of the transitional layer growth show direct logarithmic dependence. Using non-contact atomic force microscopy, the growth of the transitional film was observed. Using atomic force microscopy in non-contact regime, time dependent measurement was done and the process of forming of one monolayer of the transitional layer was documented. Within the diploma thesis, a series of experiments on ultra high vacuum system were performed in order to investigate phase transformation of thin Fe films (22 monolayers) on Cu(100) stabilized by CO absorption. The transformation from fcc phase to bcc phase was induced by Ar+ ion beam bombardment with the ion energy in the range (0.5-4) keV. The process of phase transformation was observed by surface magneto-optic Kerr effect, Auger electron spectroscopy and low energy electron diffraction.
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Phase Transformations during Heat Treatment of Fe - C Materials
Škvarka, Jakub ; Pacal, Bohumil (referee) ; Molliková, Eva (advisor)
The goal of this thesis is a study of heat treatment of iron-carbon alloys from a physical angle. Characteristics of main components from this system and their modifications are described there. There is also described what is going on during heat treatment especially from an angle of thermodynamics and kinetics, thanks to available information from literature. The knowledge is applied on specific types of heat treatment of material and processes which can follow it.
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