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Optimalization of experimental method for study on penetration of humic acids into leaves.
Smilková, Marcela ; Pekař, Miloslav (referee) ; Sedláček, Petr (advisor)
This bachelor’s thesis is focused on the study of penetration of humic substances trough the plant cuticle. The main objective of the thesis aimed at a literature search on foliar fertilization and transport of substances in the plant leaves. According to the literature search, experimental technique was suggested and tested in order to study penetration of humic substances through the leaf cuticle. The method consists of observation of diffusion transport of humic acids between two inert agarose gels separated by the plant cuticle. Cuticles were prepared by the means of three different isolation procedures.
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Fatigue properties of AZ61 magnesium alloy
Provazníková, Andrea ; Juliš, Martin (referee) ; Pantělejev, Libor (advisor)
This master’s thesis is dealing with low-fatigue behavior of magnesium alloy AZ61, prepared via squeeze casting method. The main aim of this work was to obtain the basic mechanical properties as well as the low cycle fatigue data. Additional metallographical evaluation of microstructure and fractographical analysis after fatigue tests was made.
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The Influence of Nanoparticles on The Properties of Hard Polyurethane Foams
Eliáš, Filip ; Kotlík, Josef (referee) ; Petrůj, Jaroslav (advisor)
The theoretical part of the thesis focuses on general principles of polyurethane chemistry. Nanotechnologies are also discussed, in particular using nanoparticles in the production of polyurethane foams. There are also mentioned selected preparation methods of silver and titanium dioxide nanoparticles. The experimental part describes mainly a novel method for synthesis of the concentrated solution of titanium dioxide nanoparticles in glycerol and their analysis by using confocal microscopy, scanning electron microscopy, dynamic light scattering and UV-VIS spectroscopy. Finally, there are suggested particular steps for further investigation of prepared nanoparticles for the production of rigid polyurethane foams, and also for other applications.
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Physical Load Analysis In Woman's Beach Volleyball
Maciolková, Hana ; Vorálek, Rostislav (advisor) ; Buchtel, Jaroslav (referee)
Title: Physical Load Analysis In Woman's Beach Volleyball Objectives: The objective is to examine time characteristics, cardiac strain, movement pattern and the individua! volleyball skills in woman playing beach volleyball. The results will help aid athletes and coaches to improve individua} and team performance in the sport. Methods: Analyses of the thirteen game records were used to compile data for statistical time measurements, movement pattems and individua! volleyball skill. Through the use of sport testers, four individua} athletes in four separate toumaments had their heart rates recorded. These heart rates were further analyzed to collect the appropriate data for cardiac strain characteristics. Results: The average game time was 37 minutes with 5 - 9 seconds exercise loads and 15 seconds recovery time. Beach volleyball is high to middle level intensity game with mixed aerobic- anaerobic energy supply system in use. The average heart rate falls in the interval of 150 and 180. The jumping load is about 41 and more jumps counting serve jump, block and spike. The prevalent movement distance is within 4 meter range. The results also shows that the blocking player is under large physical stress while changing repeteadly position between defence on the net and in the field. Keywords: Beach...
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Study of the synthesis and structure of ceramic perovskite materials for energy applications
Strejček, Josef ; Bartoníčková, Eva (referee) ; Cihlář, Jaroslav (advisor)
Method, so called “glycin- nitrate process”, combined with high temperature solid state reaction, of preparation multi- component ceramic perovskite materials was studied. Two types of perovskite systems were prepared by this method. Firs one, based on LaNiO3 doped by calcium and aluminium and second one, based on SmFeO3 doped by calcium and nickel or cobalt. This method made possible preparation of one phase perovskite or perovskites with few percent of nickel in form of oxide. In systems containing both nickel and calcium another phases rich in calcium and nickel appeared.
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Propagation of inclined cracks to the interface of ceramic laminates
Novotná, Lenka ; Trunec, Martin (referee) ; Chlup, Zdeněk (advisor)
Composite materials with laminated structure provide advantages which are utilised during component design. Low density, temperature and chemical stability are the profitable properties predetermining application of ceramic laminates. The main obstacle for wide spread of ceramic materials is their inherent brittleness. Therefore, in this thesis, the crack propagation in ceramics laminates has been extensively studied. Laminated structures with various volume fractions of components (alumina and zirconia) were prepared by electrophoretic deposition. Evaluation of crack propagation through the interface and determination of basic mechanical properties was conducted on the basis of extensive literature search. Crack deflection originated in both presence of internal stresses and differences in elastic modulus during the crack interface passing was monitored. A special type of specimen geometry was employed with the aim to set arbitrary angle between crack and interface. It was experimentally found that the degree of crack deflection is dependent on entering angle and volume fraction of components. Higher crack deflection was already found in the bulk of the test piece comparing to the test piece surface. The 3D fracture surface reconstruction generated using laser confocal microscopy was used in this detailed crack propagation study. Further basic elastic and strength characteristics of laminates were determined and compared to those obtained from monolithic materials. The validity of the mix rule for elastic characteristics was confirmed by comparing of elastics modulus. The most reliable method for elastic modulus determination was marked the dynamic resonance method due to low scatter and consistency in measurement. The flexural strength of all laminates tends to be close to the flexural strength of the weakest component. Therefore the mix rule is not applicable for flexural strength estimation on the contrary of elastic characteristics. The change of component volume fraction leads only to change of flexural strength scatter. Thanks to gained knowledge about crack propagation and basic characteristic determination will be possible to design ceramic laminates more efficiently for given needs of application.
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12M-IMMEDIATE Research Report: Preparation of Pt on Carbon Black Supported Catalysts
Kaluža, Luděk ; Zdražil, Miroslav ; Gulková, Daniela ; Vít, Zdeněk ; Šolcová, Olga ; Soukup, Karel ; Maixnerová, Lucie
The aim of this work was to elucidate on advanced preparation of Pt/C catalysts from TimCal carbon black and H2PtCl6. The attention was directed to residual content of chloride in the prepared catalysts and scale-up to the amount about 1 gram of final product. The textrual properties of the supports and selected catalyst were studied by nitrogen physisorption. The analytical methods such as instrumental neutron activation analysis (INAA), liquid ion chromatography (LC), and titration with silver nitrates were applied for Cl analysis. Electron probe micro analysis (SEM-EDX), hydrogen chemisorption, temperature programed desorption of hydrogen (TPD) and a simplified determination of ignition temperature in air flow were used for Pt/C catalysts characterization.
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Achievement motivation in synchronized swimming training
Kopecká, Kateřina ; Jurák, Daniel (advisor) ; Peslová, Eva (referee)
Název práce: Výkonová motivace v tréninku synchronizovaného plavání Cíle práce: Cílem diplomové práce je pomocí dotazníkové metody zjistit, jakým způsobem trenéři synchronizovaného plavání motivují své svěřence v tréninku a v průběhu soutěží. Na základě získaných informací vytvoříme doporučení, které bude trenérům v praxi nápomocno v řešení problematiky motivace v tréninkovém procesu. Metoda: Experiment bude prováděn metodou kvalitativního dotazníku sestaveného pro trenéry synchronizovaného plavání na území ČR. Klíčová slova: synchronizované plavání, sportovní výkon, psychologická příprava, motivace, výkonová motivace, prostředky regulace, trenér Abstrakt Title: The Achievement Motivation in Synchronized Swimming Training The Aim of The Thesis: The aim of the thesis is to find out how the coaches of synchronized swimming motivate their athletes during training and competitions. We will create recommendation for coaches based on recieved information. This suggestions will be helpfull in solving the problems of motivation in training. Method: Experiment will be provided by using qualitative questionnaires established for synchronized swimming coaches in the Czech Republic. Key Words: synchronized swimming, sports achievement, psychological preparation, motivation, achievement motivation, means of...
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