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Interaction between TiAl melt and coated oxide refractories
Dočekalová, Kateřina ; Dlouhý, Antonín ; Zemčík, L. ; Fiala, J.
The present study focuses on reactions between ceramic crucibles and molten TiAl intermetallics. Coating strategies are investigated that exhibit a potential in slowing down the decomposition of the crucible wall. Uncoated crucibles (system TiAl melt - Al2O3 crucible) and crucibles with the coat (system TiAl melt - CaO coat - Al2O3 crucible) were used in melting and casting experiments. The reference state of the coated crucible before the melting trial was also investigated. Results of the SEM, EDAX and X-ray diffraction analysis contributed to the identification of the reaction zone and its chemical composition. The melt contamination with oxide inclusions results from the erosion process in which individual components of the melt diffuse along grain boundaries of the refractory and activate chemical reactions that decompose the crucible wall. Assessment of thermodynamic parameters associated with the chemical reactions helped in identifying the nature of the erosion process.
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Vakuová metalurgie intermetalik TiAl
Zemčík, L. ; Dlouhý, Antonín ; Król, S. ; Pražmowski, M.
To be able to melt successfully type gamma TiAl alloys it is absolutely necessary to solve the fundamental metallurgical problems associated with the reactions between the melt and the refractories of crucibles and ceramic moulds, with the reactions between the melt and residual gases in the furnace chamber, and with the evaporation of aluminium from the melt. The paper deals with the physico - chemical analyses of the above processes and gives their evaluation based on the results of experimental melts of the type of Ti48Al2Cr2Nb1B (at.%) obtained in vacuum induction furnace. The work also gives the results of oxidation tests for the Ti48Al2Cr2Nb1B(at.%) alloy.
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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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Splicing of atypical introns in S. cerevisiae
Cit, Zdeněk ; Půta, František (advisor) ; Pichová, Alena (referee)
Pre-mRNA splicing is a vital process of gene expression important for all eukaryotic organisms. For the proper function of this very complex and dynamic event the presence of few specialized RNA and many proteins that hold a variety of tasks is necessary, not only inside the splicing complex itself, but also beyond this complex. The Prp45 is one of the proteins involved in pre-mRNA splicing in yeast Saccharomyces cerevisiae. Its human homologue, SNW1/SKIP, is involved in splicing but also in other crucial cell processes. The Prp45 protein was reliably reported only to participate in the second transesterification reaction of splicing. But there are also data suggesting its possible involvement in the first transesterification reaction. This work provides further evidences linking protein Prp45 with the first splicing reaction, obtained by the research of cells carrying the mutant allele prp45(1-169). Cells carrying this allele show dropped splicing and accumulation of pre-mRNAs. This thesis therefore also investigated the possible influence of Prp45 protein on the RNA export from the nucleus to the cytoplasm. But no connection between this protein and RNA transport was discovered. Keywords pre-mRNA splicing; Saccharomyces cerevisiae; Prp45; Mer1; Mud2; Prp22; Rrp6; AMA1; SNW1/SKIP
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An Athletic Club
Hmirová, Marcela ; Vindušková, Jitka (advisor) ; Krátký, Petr (referee)
AN ATHLETIC CLUB Thesis objectives: The aim of this diplomy thesis is to provide a description of my work with an athletic club. The objectives are organization, contents of the activities and children's reactions. Methods: While working on the thesis I used these methods: observation, symposium, discussion and description. From my point of view the most effective method was a discussion. Children could express their attitude towards the given activity. Results: Children of the age 6 to 9 rather play group games and activities. Those 10 and 11 years old prefer competing with each other, where they can compare their performance with friends. Keywords: athletics, an athletic club, exercise, children, competition, game
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Agression measurement and assessment using methods of psychological diagnostics
Harsa, Pavel ; Žukov, Ilja (advisor) ; Hynek, Karel (referee) ; Kratochvíl, Stanislav (referee)
We have tried in doctoral thesis to objectively verify usability of questionnaires and projective methods in evaluation of aggressiveness of psychiatric patients. In the theoretical part of the study we discuss definitions of aggression and aggressiveness. There is a number of theoretic interpretations of aggressiveness and aggression in which these general terms are characterized. Most authors and single theory are in full agreement of views that there are two types of aggression, aceptable and unacceptable for society. We have aimed at bio-psycho-social aspects of aggression and the structure of aggressive personality. Nowadays there are many branches of science, which are engaged in aggressiveness, for example genetics, biology and psychology. It is evidence to support the view that aggressiveness is a serious problem in human society. At the same timee it is difficult to find empiric assessment of aggression. (...) In conclusion: These results verify clinical and forensic experience with assessment and measurement of aggressiveness. Test methods show much more general temperament dispositions, tendency to emotional reaction and to explosive reactions. Information and experience from this thesis could be helpful for assessment of emotional aggression in psychiatric patients and for forensic practie....
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Diagnostics and therapy of spiritual emergency - orienting study
Janečková, Barbora ; Bahbouh, Radvan (advisor) ; Břicháček, Václav (referee) ; Hájek, Karel (referee)
The doctoral dissertation contains of a definition of spiritual emergency, differential diagnosis, description of kinds of spiritual emergency. It looks on the therapeutical possibilities in working with these states. Part of the dissertation is analysis of semistructured interviews with clients and therapists who work with these kinds of problems. In the analysis of the interviews with therapists I center on their experience with the dynamics of spiritual emergence, its manifestation and possible existence of similar traits of clients with this diagnosis. Important parts of the interviews are the most effective ways of working with these clients. I was also interested in their own perception on how spiritual emergence occurs and on the possible change in the quality of life of the client after this episode. In the analysis of the interviews with the clients I question when spiritual emergence occurred, how it started, how long did it last and what were the reactions from outside. Important part is centered on the interventions which the client experienced and their efficiency. Case studies demonstrate typical traits described at spiritual emergency, as quite dramatic beginning, complete recovery and also an important change in value system.
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Synthesis and cytostatic activity of 3,5-disubstituted pentenolides analogous to gelastatin
Pavlík, Jan ; Pour, Milan (advisor) ; Starý, Ivo (referee) ; Dvořák, Dalimil (referee)
Within the framework of this thesis, a large series of 5-(acyloxymethyl)-3-aryl-5,6- dihydro-2H-pyran-2-ones was prepared and their cytostatic activity investigated. The key steps in the preparation of the compounds were alkylation of esters of substituted phenylacetic acids with 2-iodomethyl-5,5-dimethyl-1,3-dioxane, followed by cyclization to furnish a saturated lactone into which a double bond was introduced in the next step. Some of the target compounds displayed interesting cytostatic activity (IC50 < 10 µmol/L) against a panel of standard cell lines including both leukemic cells and those derived from solid tumours. The activity against colorectal carcinoma HT29 cell line, which is otherwise resistant against the standard combination of cytostatic agents used in the treatment of these tumours is especially remarkable. In the next part, the development of the synthesis of the 5-alkylidene analogues of these compounds, which are also analogous to bioactive natural products, such as the gelastatins and CR377, is described. Successful strategy is based on the use of 2-iodo allylic alcohols as the starting materials, which are converted into the target 3-substituted-5-alkylidene pentenolides via an array of Pd-catalyzed reactions, including Sonogashira coupling with methyl propiolate,...
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