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Effect of Organic Additives on Electrochemical Processes Influencing Zn-Air Battery parameters
Smejkal, Jan ; Čech, Ondřej (referee) ; Chladil, Ladislav (advisor)
The diploma thesis is focused on the study of the influence of selected organic additives on the properties and morphology of zinc deposit on the negative electrode when used in zinc-air accumulators. Organic additives have been selected based on the study of literature and previously done experiments. The deposition was made on the tin plate electrodes in a solution of 6 mol/l KOH saturated with ZnO with added additives. All chosen additives were studied with a focus on the morphology of zinc deposit and with regard to their ability to suppress dendritic growth. Zinc morphology was studied by using a Tescan Vega 3 electron microscope and a Rigaku MiniFlex HR 600 X-ray diffractometer.
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Morphology of Polyamide 12 and Polyamide 11 formed at overpressure and underpressure
Bělašková, Marie ; Tocháček, Jiří (referee) ; Bálková, Radka (advisor)
In this master thesis it was studied morphology of polyamide 12 (PA12), polyamide 11 (PA11) and their blends in the percent ratios 95/5, 75/25, 50/50, 25/75 and 5/95 formed at pressure 7 MPa in a calorimeter both after continual heating and cooling and after annealing and isothermal crystallization. Neat polyamides and blends were further characterized by thermogravimetric analysis, differential scanning calorimetry at atmospheric pressure, Fourier-transform infrared spectroscopy in attenuated total refection, and X-ray diffraction analysis. The increased pressure improved level of polyamide chains ordering in crystal lamellae. Thermal annealing improved especially ordering of PA12, isothermal crystallization led to considerable increase of crystallinity, whereas PA11-rich blends supported perfection of PA12 crystals. Partial transformation of - to -structure occurred in case of neat PA12 at high pressure, the change of the chain conformation into the closer one occurred in neat PA11 without transformation of the type of crystal structure.
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Effect of body fluids on setting, structure and mechanical properties of phosphate bone cements
Bednaříková, Vendula ; Michlovská, Lenka (referee) ; Vojtová, Lucy (advisor)
Předložená diplomová práce se zabývá přípravou a charakterizací vzorků z kompozitního kostního cementu na bázi fosforečnanu vápenatého (CPC). V teoretické části jsou popsány vlastnosti a struktura fosforečnanů vápenatých, včetně jejich interakce s tělním prostředím. Experimentální část nejdříve popisuje stanovení optimální techniky přípravy vzorků pomocí experimentů prováděných v ultračisté vodě. Optimální technika pro vytvrzování zahrnuje použití formy z paměťové pěny, ukončení vytvrzovacích reakcí pomocí absolutního chladného etanolu a sušení vzorků ve vakuové sušárně. Následně je v práci popsána příprava vzorků a proces vytvrzování CPC jak v přirozeném (prasečí krev), tak v prostředí simulovaných tělních tekutin (fyziologický roztok, Hankův a Ringerův roztok). Byla provedena morfologická studie pomocí skenovací elektronové mikroskopie (SEM) pro vzorky vytvrzené 1 den, 1 týden, 2 týdny a 1 měsíc kvůli očekávané významné změně v jejich krystalické struktuře, která byla taktéž zkoumána pomocí rentgenové difrakce (XRD), stanovující přeměnu -fosforečnanu vápenatého na kalcium deficitní hydroxyapatit (CDHA). Porozita vzorků byla zkoumána rentgenovou mikrotomografií (-CT) a vzorky vytvrzené v krvi vykazovaly mírně vyšší porozitu. Mechanické vlastnosti CPC vzorků byly zkoumány pomocí mechanických kompresních testů. Výsledky testů ukázaly stabilní pevnost cementových vzorků vytvrzených ve fyziologickém roztoku už po jednom dni vytvrzování, zatímco vzorky vytvrzené v krvi vykazovaly nárůst pevností dokonce i po jednom měsíci vytvrzování. Naopak pevnost vzorků vytvrzených jak v Hankově, tak v Ringerově roztoku rychle klesla po 2 týdnech vytvrzování pravděpodobně důsledkem mírně kyselého pH vytvrzovacích roztoků, které urychluje rozpad CPC vzorků. Výsledky práce ukazují významný vliv vytvrzovacích prostředí na vlastnosti CPC kostních cementů. Vzorky vytvrzené v krvi oproti vzorkům vytvrzených v umělé tělní plazmě vykázaly lepší vlastnosti, protože krev imituje in vivo podmínky.
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Synthesis of ferroelectric and dielectric ceramic composite materials
Čípová, Eva ; Salamon, David (referee) ; Částková, Klára (advisor)
The topic of the thesis is preparation of ferroelectric and dielectric composite materials, particularly the work deals with the preparation of barium strontium titanate. In the theoretical part the possibilities of BST synthesis and its processing are described. The experimental part deals with precipitation synthesis of barium strontium titanate. Prepared powders were characterized in terms of morphology and phase composition. Further, pressureless sintering and hot isostatic pressing (HIP) were used for preparation of dense ceramics. Pure BST powders, that were formed and sintered, were prepared by sol-gel precipitation synthesis. The highest density was reached by slow sintering cycle (slow increase of temperature and delay during sintering) and sintering by HIP.
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Derivational Morphology of Czech on Large Corpus Data
Faltusová, Marie ; Dytrych, Jaroslav (referee) ; Smrž, Pavel (advisor)
Subject of this thesis is study of word formation in the Czech language. The main aim is to create a module acquiring derivations from data of the electronic Dictionary of the Czech Language. This problematics has been solved by constructing three-level processing based on dictionary data. The first level is to obtain derivations from lemma definitions, the second step is making groups of basic forms according to their similarities, and the third stage is the evaluation of derivation pairs by number tag of derivation class to which they belong. I have managed to get more than 4 500 new words and evaluate over 20 000 derivative couples. The module has become a full-fledged part of the Morphological Analyzer of the Knowledge Technology Research Group, working at the Faculty of Information Technology of the Brno University of Technology.
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The Gallery of Brno Grand Prix
Sikora, Zbigniew ; Boleslavská, Yvona (referee) ; Žalmanová, Petra (advisor)
The main task of this thesis was to create an architectural study of The Gallery of Brno Grand Prix based on previous urban study from previous semester works. The proposal is focused on the iconic circuit’s former glory restoration, on providing new content for raceway complex and creating decent and presentable place for the presentation of the rich history of Czech and Czechoslovak motorsport. The result is a study of an object that meets these needs while respecting the historical and morphological values of the place. The building creates new themed attraction and creates the potential for further development of near circuit.
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Information Technologies in Psychology
Ižák, Tomáš ; Fapšo, Michal (referee) ; Smrž, Pavel (advisor)
This work is interested in possibilities of personal character's recognition from text data with computer contribution. It's based on Kreitler & Kreitler method that's why it's focused on separating sentences into meaning units, assigning a dimension to a meaning unit and gaining characters of author (neuroticism and extroversion) from meaning unit's dimensions.
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Metallurgy and properties of heavy steel castings
Kubík, Jiří ; Čech, Jan (referee) ; Záděra, Antonín (advisor)
The work deals with the determination of the chemical composition and morphology of inclusions in experimental casting foundry in operating conditions as ŽĎAS in compliance with the optimum content appropriate deoxidation depending on the conditions of solidification. The introductory part is devoted to theoretical analysis of possible defects in castings. We also describe the experimental casting, sampling sites and their markings. Subsequently evaluated morphology microanalysis inclusions and the effect of inclusions on the mechanical properties and the formation of defects in the casting. The conclusion summarizes the results and proposal for further direction in the production of heavy steel castings.
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