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SMV-2012-15: Examination of microstructure of heat-proof steels by means of the low energy electron microscopy
Mikmeková, Šárka
The CB steel is meant for casted components of turbines – valves and shell. From the COST F and COST FB2 steels, welded rotors are made similarly as from a combination of the F steel and a nickel alloy, which is, however, used for higher temperatures. In order these materials preserve their desired strength for long-time load at high temperatures, slip movement of dislocations should be effectively blocked. In the given materials, this is secured with the help of fine precipitates, which, however, coarse during exploitation and are replaced with particles of different phases that have reduced ability to retard the dislocation movement. By means of the low energy electron microscopy the microstructure of heat-proof metallic materials has been examined, which provided detection and chemical and phase classification of tiny particles of the fine precipitates.
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Use of transition metal catalyzed reactions in synthesis of biologic active compouds
Novák, Petr ; Kotora, Martin (advisor) ; Veselý, Jan (referee) ; Čermák, Jan (referee) ; Pour, Milan (referee)
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Syngas Cleaning with Using Metal Catalysts
Baláš, Marek ; Noskievič, Pavel (referee) ; Kabát, Viktor (referee) ; Skála, Zdeněk (advisor)
Gasification of biomass is a one of the several technologies for energy production from biomass. Biomass is a promising renewable source of energy and is in a centre of attention of energy industry not only in the Czech Republic, but also in the EU and in the world. Gasification is a thermo chemical transformation of fuel with access of understoicheiometric amount of oxidizer which produces gas of low heating value. Its main combustible components are hydrogen, carbon dioxide and methane. Produced gas may be further used in power and heating plants. Besides combustible and neutral components, gas also contains pollutants such as sulphur compounds, chlorine compounds, ash and tar. It is tar which is considered to be the underbelly of gasification as it causes, along with ash, fouling in transport tracks and terminal equipment, and blocks direct application of gas. This dissertation thesis presents design of filter for elimination of tar from the gas generated in fluid gasification equipment. This work is closely related to current research at Energy Institute at Faculty of Mechanical Engineering at Brno University of Technology. First part deals with theoretical background of this issue. Biomass properties are mentioned in relation to gasification. Types of gasification equipment are described and principle of gasification including chemical reactions is given in detail. Special part is dedicated to pollutants in the gas, especially to production of tar and its properties, which is important for consequent work. Main focus is on possibilities of catalytic cleaning of gas from tar. Principle of tar decomposition is described and types and properties of catalysts are given. Part of the thesis tackles the issue of real operations and loss of efficiency of catalyst due to sulphur compounds, sintering and carbon fouling. Based on experience and analysis in the first part of the thesis, concept of elimination of tar from gas was laid out. In addition to that, method for measurement at Biofluid 100 experimental unit was outlined and filter for testing of industrial catalysts using metal was designed. Series of experiments were further conducted in order to find out efficiency of three opted catalysts for tar decomposition. Results of these experiments are described in detail and assessed in the conclusion of this thesis which also contains outline for economic assessment of method of gas cleaning using catalysts.
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Hydrodesulfurization CoMo/Al2O3 and CoMo/C Catalysts Prepared with Nitrilotriacetic Acid without Use of NH4OH
Kaluža, Luděk ; Zdražil, Miroslav ; Vít, Zdeněk
We have calculated and experimentally confirmed that in the catalysts without NTA before sulfidation, the deposited phase takes up only about 5% of the pore volume of Al2O3 support. The deposited Co-Mo-O phase forms a monolayer and all Co-Mo-species are in physical and chemical contact with the support surface. In NTA catalysts before sulfidation, the deposited NTA-Co-Mo phase takes up about 60% of the pore volume of Al2O3. During sulfidation, the metal-support interaction of the majority of the Co and Mo species is blocked not only chemically by their own NTA ligands, but also physically by the surrounding supported solid. The majority of deposited solid in dried NTA catalysts is sulfided as if it were in the unsupported form. This leads to different morphology and structure of Co-Mo sulfides as compared with the catalysts without NTA. It was concluded that the overall NTA action is a combination of not only chemical effects described in the literature, but also of the above physical effect.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22014082908312 - PDF
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Design of structures with FRP reinforcement
Matušíková, Anna ; Vácha, Jaroslav (referee) ; Štěpánek, Petr (advisor)
This diploma thesis presents available FRP software for calculating load bearing capacity of the structures reinforced with FRP and compares them between each other. Furthermore theory and algorithm of my own software is presented here. Load bearing capacity of structures which are reinforced with non-metallic reinforcement and loaded by combination of normal force and bending moment can be solved by my programme. Effects of high temperatures on the concrete structures can be included in the calculation. In the second part of the thesis is calculated load-bearing capacity and deflection of the real beam reinforced with FRP reinforcement and load-bearing capacity of member with FRP reinforcement with effect of elevated temperature. This has been done using my software. Comparison of results from hand calculation and laboratory load-bearing testing is done at the end. This laboratory testing was accomplished by Institute of Concrete and Mansory Structures at our faculty.
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Raw materials of Manětín area and their presentation in the form of educational patthway
Čada, Martin ; Přikryl, Richard (advisor) ; Matějka, Dobroslav (referee)
This bachelor thesis focuses on the geological history (Late Proterozoic to Quaternary) of the Manětín Permian-Carboniferous basin. It also studies the historical and present use of raw materials (ores, non-metallics, caustobiolites) in the Manětín area, the northern part of the Plzeň-sever district. In appendix, information panels of the educational pathway are proposed. The Manětín basin consists of two structural levels. The lower one (Proterozoic metapelites) forms the base of the basin. The upper one (Permian-Carboniferous clastic sedimentary rocks) is the filling of the basin. There are also a few Proterozoic and Tertiary volcanic bodies. In the past, ore deposits (gold, silver, iron) had been exploited in the Manětín area. Non-metallics (glass sand, ocher, pyrite-slate, roof-slate, structural clay products, arkose) had been largely used, too. There was only a small scale extraction of caustobiolites (humites). Today's extraction is focused on natural stone (crushed stone) only (Zahrádka and Březín deposits). The proposal of the educational pathway contains seven information boards, that show the geological history of the Manětín basin and the use of local mineral raw materials (gold, slate, natural stone) with it's influence on the landscape, society and industry, particularly glass production. The...
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Structure and magnetism of transition metal-based nanoparticles
Mantlíková, Alice ; Kalbáčová Vejpravová, Jana (advisor) ; Prchal, Jiří (referee)
The aim of the work is characterization of structure and magnetic properties of various CoFe2O4/SiO2 nanocomposites. Emphasis was put on the corelation of the magnetic properties with particle size (samples with different annealing temperature) and with strenght of the interparticle interactions (samples with different Fe/Si ratio or without silica matrix). Structure properties of all samples were determinated by powder x-ray diffraction, scanning and transmission electron microscopy. Magnetic properties were determinated by standard (temperature dependence of magnetization, magnetization isotherms) and advanced (a.c. susceptibility, memory effects) magnetic measurements. A sharp increase of the values of blocking temperature and coercivity with increase of strenght of the interparticle interactions and with increase of particle size was observed. Particle size determines the maximum value of coercivity and blocking temperature and strengh of the interparticle interactions shift this values in the interval determined by particle size.
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Contributions to Volatile Compound Generation of Arsenic, Silver and Gold by Tetrahydroborate Reaction for Atomic Absorption Spectrometry
Musil, Stanislav ; Rychlovský, Petr (advisor) ; Kanický, Viktor (referee) ; Spěváčková, Věra (referee)
(EN) The presented dissertation thesis summarizes the results contained in five original research papers that were published in prestigious international scientific journals in the field of analytical chemistry and atomic spectrometry. It is devoted to the method of generation of volatile compounds using a tetrahydroborate reaction and detection in a quartz multiatomizer by atomic absorption spectrometry. The thesis can be divided into two thematic parts - speciation analysis of arsenic based on hydride generation technique with collection and separation in a cryogenic trap and generation of volatile species of transition metals. In the first thematic part pre-reduction of pentavalent inorganic and methylated arsenicals has been studied. A simple setup for on-line pre-reduction employing thioglycolic acid as a fast pre-reductant has been developed, connected with a current hydride generator and applied/verified to oxidation state specific arsenic speciation analysis of human urine samples. In the same method the possibility of drying the gaseous phase from water vapor has been investigated to avoid incidental blocking the cryogenic trap by frozen water and to decrease fluctuations of signal baseline. Pronounced losses of methylated species have been discovered on Nafion tube dryer currently used in...
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Synthesis of unsymmetrical derivatives of azaphthalocyanines IV.
Dvořáková, Zuzana ; Zimčík, Petr (advisor) ; Doležal, Martin (referee)
Synthesis of unsymmetrical derivatives of azaphthalocyanines IV. Zuzana Dvořáková Department of Pharmaceutical Chemistry and Drug Control, Faculty of Pharmacy in Hradec Kralove, Charles University in Prague, Heyrovskeho 1203, Hradec Kralove, 50005, Czech Republic Phthalocyanine (Pc) and their azaanalogues (AzaPC, which have some carbons in their macrocyclic system replaced by nitrogens) belong to group of photosensitizers, which are used for photodynamic therapy in treatment of various cancer diseases. The effect is given by ability to generate reactive oxygen species (e.g. singlet oxygen) after light absorption. The aim of the work is to synthesize AzaPc with optimal properties and with a high efficiency in singlet oxygen production. New unsymmetrical AzaPc with different numbers of pyridyl on periphery were synthesized with zinc as central metal. Different ZnAzaPc were prepared using a statistical condensation starting from two precursors (5,6-bis(tert-butylsulfanyl)- pyrazine-2,3-dicarbonitrile (A) and 5,6-di(pyridin-2-yl)pyrazine-2,3-dicarbonitrile (B)). From the mixture of six posibble AzaPc, four of them (AAAB, ABAB, AABB, ABBB) were isolated by column chromatography. The symmetrical (AAAA, BBBB) substances were not isolated from the mixture, they were compared with standards. All prepared substances...
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Restrictions on activities of the courts during emergencies
DOSTÁL, Petr
The thesis discusses the limitations of courts during emergencies and the meaningfulness of the classification system of justice in critical infrastructure. Judicial power is in addition to legislative and executive branches in a classic triangle of state power. The scope of its activities is to introduce the first part. With an analysis of relevant laws to the reader's raised the breadth and importance to society. The text below is followed by a list of incidents that affect the limitations on the exercise of judicial power. They provide a list of departmental emergency preparedness plan and have added two new current threats. The last part of the introductory essay to speak of critical infrastructure, which includes the judiciary. The thesis aims to determine how the judicial administration immune to the impact of emergencies. Whether the system needs more investment in security measures applied so far as eliminating the effect of well-defined emergencies, and if justice is rightly placed in the framework of critical infrastructure. For the actual processing of the results is the methodology used in operational analysis. Specifically, it is the discipline of multi-criteria evaluation of alternatives. The method itself is appropriate for the assessment of phenomena, where the value of multiple criteria. The results are processed according to the principles of the WSA (weighted sum) and Fuller (comparison and scoring method). Naturally, there is comparison of the results of both disciplines. Examined measures designed to limit exposure incidents are classified into thematic blocks. The ranking of construction services, technology, internal structure and physical site security. Taking the first and third block is formed by means of passive protection and the second and fourth block is formed by means of active defense. It is interesting comparison between the blocks and those stand block. A summary of results and their own and departmental analysis of threats to judicial authorities indicate readiness for the events listed in the Plan of departmental emergency preparedness as an emergency.
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