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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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Modelling of Phase Composition of Heat Resistant Steels and their Welds
Dvořáček, Ondřej ; Foret, Rudolf (referee) ; Jan, Vít (advisor)
This work deals with the effects of high temperature exposition of low alloyed creep resistant steels on their structural stability and structural stability of their weld joint. The theoretical part of this work gives an overview of creep resistant steels considering their chemical and phase composition and their connection to high temperature mechanical properties. The CALPHAD method is presented as generally accepted approach for equilibrated calculations and Thermo-Calc and DICTRA software packages are introduced as CALPHAD applications. Thermo-Calc software is used for calculation of phase composition of the examined materials and for calculation of the phase diagrams. Software DICTRA is used for simulations of diffusion controlled phase reactions in the analysed weld. Experimentally one weld joint of the steels 15 128 and 15 313 has been studied after four different annealing procedures. The experimental results include chemical profiles across the welds, microhardness profiles and metallographic analysis of significant regions of the welds. These experimental results are compared with the simulation results. The comparison shows a reasonable agreement between experimental and simulation data.
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Application of Technique of Oriented Foils in TEM
Buček, Petr ; Kruml, Tomáš (referee) ; Petrenec, Martin (advisor)
The master’s thesis is focused on the application of the technique of oriented foils in transmission electron microscopy. Dislocation structures were identified by this technique in both phases of polycrystalline austenitic-ferritic stainless steel SAF 2507 formed during low cycle fatigue at two plastic strain amplitudes ap. In individual grains the stress axis and the Schmid factors of active slip systems were determined. In austenitic grains, the planar structures were determined at both ap. In ferritic grains, the dislocation arrangement was different for the two observed ap. Individual screw dislocations and pile-up´s of edge dislocations were found at low ap = 1x10-4. Mixture of vein and wall dislocation structures were formed at high ap = 2x10-3. Observed dislocation structures were discussed in relation with the cyclic plastic response of the duplex stainless steel.
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Analysis of drive corned filler including feed worm and conveyer
Mahút, Tomáš ; Dočkal, Aleš (referee) ; Dvořáček, Jiří (advisor)
This final project solves a proposal of mechanism for splitting of unfilled cans before a can filling process in the food industry. From all possible options such as the one with a simple conception, easy applicated in practice and at a low price, should be chosen. The selected option is constructed and drawn in a 3D programme called AUTODESK Inventor 10. Please, see the attached technical drawings for the chosen parts.
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Analysis EKG by paramedic in pre-hospital care
KOLLNEROVÁ, Kateřina
This Bachelor thesis deals with the issue of monitoring and evaluation of electrocardiography (ECG). The monitoring of ECG belongs to the basic diagnostic methods of heartbeat. It is also irreplaceble in prehospital emergency care (PEC). That is why a paramedic must be sure in manipulation with the ECG machine and he or she must faultlessly distinguish typical deviations in ECG curve, especially in case of life-threatening and frequent arrhythmia because a proper treatment in PEC usually has a decisive influence on a patient´s life. In the theoretical part of the thesis I dealt with basic knowledge about the anatomy and physiology of heart. Then I focused on electrocardigraphy as a basic diagnostic method, I mentioned various types of ECG and described ECG machine used in PEC. I also delineated electrodes and downspouts and their classification. I added a procedure of monitoring ECG by means of defibrillation electrodes and by means of downspouts. In the next chapter I dealt with physiological ECG curve, its description and assessment of cardiac rhythm. A considerable part of the theoretical part is devoted to heart rhythm disorders and classification of these disorders. In the last charter I mapped options of heart rhythm disorders treatment pharmacological as well as therapy without drug application. The research part of the thesis is based on qualitative and quantitative form of research. Data were gained by method of interview and by additional knowledge test designated for paramedics from the South Moravian Region. The interviews were carried out with paramedics from the Emergency Medical Service of the South Moravian Region. The additional test consists of 16 open as well as closed questions. Results of the research were processed and depicted by means of bar charts. These express numerical value of the research results. The main aim of the thesis was an analysis of paramedics´ procedure when evaluating ECG curve. The minor aim of the thesis was to map a paramedic´s knowedge in te field of ECG curve evaluation. The theoretical part of the thesis can be used as a study material for paramedic students and also for students of other medically-oriented branches who study the issue of ECG. On the basis of the thesis results a manual was made out which could simplify the evaluation of ECG curves.
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Cemented carbides and theirs effective use
Salajka, Jaroslav ; Sedlák, Josef (referee) ; Humár, Anton (advisor)
The aim of this thesis is a complex processing of obtained technical findings in the area of cutting materials, especially the evaluation and comparison of work possibilities recommended by prime world manufacturers for effective usage and application of coated and uncoated cemented carbides. Characteristics of cemented carbides in terms of production, marking method, physical and mechanical properties and application. Comparison of cemented carbides in the range of production of the most significant world tool and cutting material producers. Cutting efficiency evaluation of the tool. Recommended areas and operating conditions for effective usage of cemented carbides and their technical economic evaluation.
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Measurement of temperature characteristics of resistivity of Cu bulk
Bartušek, Karel ; Fiala, P.
This contribution brings results of numerical modeling during design of measurement method for determine of thermal characteristic of specific resistance of Cu bulk. Combine of numerical modeling and experimental verification brings very effective procedure during suggestion and application in cryogenic region. Result of this work are used in research activities of Czech Academy of Science, ISI-Brno.
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Assessment of service conditions of the screw grips of testing machine MTS 810
Votroubek, Tomáš ; Čermák, Jan (referee) ; Náhlík, Luboš (advisor)
This diploma thesis is aimed to assessment of safety of screw grips of testing machine MTS 810. Some parts of grips are predisposed to damage at low temperature (-180°C), e.g. spacer, isolating ceramics lamellas, etc. To guarantee its perfect function under hard laboratory conditions the finite element analysis was performed and suitable modifications grips parts have been suggested with respect to maximum of application of recent parts. Part of the thesis is devoted to suggestion of suitable tightening torque of experimental sample under different temperatures. For necessary numerical computations FEM system Ansys was used.
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