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Control of Linear Motor based on Ultrasonic Detection
Veselá, Klára ; Kolářová, Jana (referee) ; Sekora, Jiří (advisor)
The focus of this bachelor thesis is to do research on possibilities of contactless distancemeasurement and linear stage construction. The first part describes four types of enginespossible to use in linear stages, their principles, advantages and disadvantages. Nextpart is focused on possibilities of contactless distance measurement. Based on thedescriptions, the most suitable modules are selected for the design of the system. Thissystem will maintain a constant distance from the object by using contactless distancesensor and linear motors.
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Influence of bases on heterogeneous Lewis acid catalyzed hydrogen transfer reactions
Veselá, Klára ; Přech, Jan (advisor) ; Bulánek, Roman (referee)
Heterogeneous Lewis acid zeolites catalyzed Meerwein-Ponndorf-Verley (MPV) reduction (transfer hydrogenation), where ketones and aldehydes are reduced to the corresponding alcohols. The hydrogen is taken from a secondary alcohol. These Lewis acid zeolite catalysts have a great advantage over homogenous catalysts as they are well separable from the reaction mixture and recyclable. Lewis acid zeolites are materials that contain incorporated tin or zirconium species, which act as Lewis acid sites. MPV reduction of citronellal provides citronellol as a product. However, the reaction of citronellal with 2- propanol also proceeds via a parallel reaction pathway providing isopulegol as the major product. Addition of pyridine (an organic base) to the reaction mixture switches the selectivity of the reaction, i.e., citronellol becomes the main product of the cited citronellal reaction with 2-propanol. It was investigated whether this phenomenon would also be observed for reactions with the addition of different bases. To answer these questions, Sn-BEA and Zr-BEA were prepared by hydrothermal synthesis. Impreg-Zr-BEA and impreg-Sn-BEA were prepared by postsynthesis metal incorporation. In addition, highly porous 2D Self-pillared pentasil zeolites containing tin and zirconium were hydrothermally synthesized....
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The fate of phosphorus in root wastewater treatment plants
Veselá, Klára ; Sobotníková, Jana (advisor) ; Nováková, Eliška (referee)
This bachelor's thesis deals with the determination of phosphorus in constructed wetlands. Phosphorus in wastewater must be eliminated effectively because there is a government regulation that permits maximal permissible concentration of phosphorus on the exit of wastewater treatment plants. Increased concentration in water leads to eutrophication, which causes the death of aquatic animals and plants. The aim of this bachelor's thesis is the validation of an easy and functional method for the determination of phosphorus in the water matrix. This method uses a complex with malachite green. The next aim was the determination of phosphate in the samples from model constructed wetlands. It's possible to make conclusions about the efficiency of model constructed wetlands out of this. For the determination UV-VIS spectrophotometry was used. The measured absorbance was recalculated to a concentration of phosphorus and after that to the concentration of phosphate. During the validation calibration, accuracy measurement, repeatability measurement, and measurement of absorbance dependence on time were performed. Sensitivity (by comparing the malachite green method with the normed method using phosphomolybdate blue), linearity, trueness, robustness, the limit of detection, and the limit of quantification were...
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Conics in projective plane
Veselá, Klára Alexandra ; Halas, Zdeněk (advisor) ; Zamboj, Michal (referee)
This master thesis deals with conics in the real projective plane. The goal was to com- prehensibly introduce conics in the projective plane to high-school students and teachers. In order to fulfill this goal, the projective plane and homogenous coordinates were intro- duced, and harmonic set and priniple of duality were studied closely. The conics in the projective plane were approached from the perspective of history, and various definitions. Well-motivated introduction of a pole and a polar was emphasized.
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Control of Linear Motor based on Ultrasonic Detection
Veselá, Klára ; Kolářová, Jana (referee) ; Sekora, Jiří (advisor)
The focus of this bachelor thesis is to do research on possibilities of contactless distancemeasurement and linear stage construction. The first part describes four types of enginespossible to use in linear stages, their principles, advantages and disadvantages. Nextpart is focused on possibilities of contactless distance measurement. Based on thedescriptions, the most suitable modules are selected for the design of the system. Thissystem will maintain a constant distance from the object by using contactless distancesensor and linear motors.
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Structural Analysis of Trickster Tales and Myths of Native Americans of North America (illustrated on the example of the tribes of Plains and Prairies)
Veselá, Klára ; Vrhel, František (advisor) ; Korecká, Zuzana (referee)
The aim of the thesis is to analyse selected trickster tales of Native Americans of North America with focus on the tales of the tribes of Plains and Prairies. The method took inspiration from was Lévi-Strausse's structural analysis. We Lévi-Starusse's terms such as mytheme, group of myths or formal structure of a myth to analyse and find a hoden meaning in a selected group of trickster tales. We call the ‚hidden meaning' the semantic meaning of a mytheme. We focused on the following mythemes: direction down and up, change and getting new physical abilities, one's ambition or wish, a prime number, duality of a mytheme. The mythemes listed above were analysed in terms of their formal structure. Then we suggested the semantic meaning of the mythemes.
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The possibility of usage of the Danube-Oder-Elbe canal for the river transportation within the countries of the central Europe
Zajíčková, Šárka ; Zelený, Lubomír (advisor) ; Veselá, Klára (referee)
This thesis analyses potential benefits of Danube-Oder-Elbe canal to the states of the central Europe. In order to do that it is necessary to describe the current importance of inland navigation within these states as well as the condition of the waterways. The main bottlenecks on existing infrastructure are the missing locks. The paper also looks into the development of support of the Danube-Oder-Elbe canal from the first reference in 1700 to the year of 2014. The last part of the work deals with the calculation of estimated direct costs and profits of the construction. Besides the direct there are also indirect expenses, which cover not only the necessary repairs and maintenance, but also external costs. External costs of inland water navigation are estimated to be six times lower than those of road transport. This difference could be a significant competitive advantage of the river transportation.
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