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Synthesis of the C15-C20 tiacumicin fragment
Havlíček, Vojtěch
In the diploma thesis, a method for preparation of the unsaturated C15-C20 tiacumicin fragment was developed. Tiacumicin is classified as a macrolidone antibiotic. Although three syntheses of tiacumicin have been recently published, this study has aimed to develop a novel pathway for its preparation utilizing catalytic reactions instead of stoichiometric ones. In the second part, an enantioselective allylation of (E)-3-jod-2-methylpropenal has been developed applying catalysis by a series of N,N'-dioxide catalysts. The asymmetric induction achieved in the allylation was up to 99% ee. This procedure allows relatively simple, straightforward and efficient preparation of wide range of natural products. Keywords tiacumicin, asymmetric synthesis, allylation, catalysis, chiral Lewis bases, organocatalysis
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Synthesis of the C15-C20 tiacumicin fragment
Havlíček, Vojtěch ; Kotora, Martin (advisor) ; Veselý, Jan (referee)
In the diploma thesis, a method for preparation of the unsaturated C15-C20 tiacumicin fragment was developed. Tiacumicin is classified as a macrolidone antibiotic. Although three syntheses of tiacumicin have been recently published, this study has aimed to develop a novel pathway for its preparation utilizing catalytic reactions instead of stoichiometric ones. In the second part, an enantioselective allylation of (E)-3-jod-2-methylpropenal has been developed applying catalysis by a series of N,N'-dioxide catalysts. The asymmetric induction achieved in the allylation was up to 99% ee. This procedure allows relatively simple, straightforward and efficient preparation of wide range of natural products. Keywords tiacumicin, asymmetric synthesis, allylation, catalysis, chiral Lewis bases, organocatalysis
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Synthesis of novel C-nucleosides with modified sugar
Havlíček, Vojtěch ; Hocek, Michal (advisor) ; Janeba, Zlatko (referee)
In this bachelor thesis, a new method of preparation of C-nukleosides with 2'-deoxy-2',2'-difluoro modified sugar part was developed. During the research, nucleophilic addition on furanolacton was used and for this modification, the method of modular approach was developed. Using this method, it is possible to prepare a series of structurally similar compounds. We succeeded in preparing two C-nukleosides, potentially biologically active substances.
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Using artifical neural network for ice phenomena prediction on the lower Berounka
Šebestová, Lucie ; Máca, Petr (advisor) ; Havlíček, Vojtěch (referee)
Ice phenomena on watercourses are commonly occurring effect in winter period. In most places do not cause any complication, but in certain places their occurrence is more frequent and in conjunction with forming ice phenomena into dangerous, as a break-up ice jam or a freeze-up ice jam, can lead to the formation of ice flood. Such places is affected lower Berounka watercourse in section Křivoklát - Vltava confluence. Occurrence and formation of ice phenomena depends on ice regime, which lower Berounka causing frequent problems. Ice regime is the interplay of many factors and ice phenomena are thus generally very difficult to predict because of strongly nonlinear relationships. Artificial neural networks excel in ability to learn on examples, in this case historical data, and ability to apply the knowledge gained on the data present and the future. This work uses multilayer perceptron neural network to realization of ice phenomena prediction based on historical flow and temperature data from the years 1887 - 1940 from the measuring station Křivoklát, which is a place of frequent occurrence of dangerous ice phenomena. The results provided by the learned neural network are comparable to the standard model used in modeling of ice phenomena. Obtained outputs confirmed the possibility of the successful application of neural networks in this area. Their use is possible as e.g. a part of information (warning) system or a system for predicting the occurrence of ice phenomena during winter season, which may lead to the alleviation of their impact on watercourse, surrounding area and residents.
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Project of small water reservoir in the cadastral area of Drsník
Šrámková, Michaela ; Havlíček, Vojtěch (advisor) ; Jan, Jan (referee)
The Diploma thesis is a project for issuance of a building permit of a small reservoir designed on the plot NO. 234/2 KN in cadastral area of Drsník. The project was drawn up at the request of the investor and according to his requirements. The purpose of the small resevoir is mainly landscape-forming and recreational but it will be use for an extensive fish farming as well. The small water reservoir is to be found on the watercourse of the brook Stržený in the Central Bohemia district approximately 8,5 km south-east of Příbram. Its area is 2457 m2 and its cubic content is 1943 m3 for the normal water level. The dam is designed as a homogenous earth one with the incline on the water side 1:3 and on the air-side 1:2 with the dam crest width 3 m. The drain system is an open runoff with two rectangular walls 2200 mm high and with runoff pipes DN 300. The safety spillway will be placed in the left dam bound and the proposed rate of flow Q100 will be proceded without an overflow of the dam crest.
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Project of small water reservoir in the cadastral area of Senomaty-Přílepy
Hoffmann, Jakub ; Havlíček, Vojtěch (advisor) ; Jiří, Jiří (referee)
This thesis is focused of design of small water reservoir in cadastral Senomaty-Přílepy. Aim of the proposal is to create a significant landscape element that will perform particularly water retention.
Reservior will flow, connected to Kolešovicky creek, which is left hand tributary of Rakovnický stream in the river basin Berounka. Planned area of water surface at normal levels is 22,75 ha. The project includes accompanying report, technical report and drawing part.
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Revitalization of small water reservoir in cadastral Nežichov
Čapek, František ; Havlíček, Vojtěch (advisor) ; Roub, Radek (referee)
This work deals with the revitalization of small water reservoir in cadastral area Nežichov. The form of project is on the level for territorial permit. As main underlay was used hydrologic data from ČHMŮ, cadastral data from ČÚZK and AutoCAD software in sense of outputs of project. In this work is also theoretic part talks about basic issues and principles of revitalization in terms of small water reservoirs.
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Design of small water reservoir in cadastral area Volenice
Harnisch, Karel ; Havlíček, Vojtěch (advisor) ; Jan, Jan (referee)
The theme of this diploma theses is project of the small water reservoir on Mačický brook in cadastral Volenice. Water reservoir is designed mainly for the accumulation function, Water reservoir can improve water flow in the catchment area behind reservoir.
In the first part of this thesis is the literature searches which process the topic of the climate changes. Designed reservoir can work as a measure for mitigation one of the consequences of climate change drought. Further this section dealt with possibilities of design of all required elements for project of water reservoir.
The second part is focused on the very characteristics of the selected area which are used as base for the design.
The third part dealt with the design of the required individual objects for proper operation of the reservoir and their verification by using hydrotechnical calculations and flood wave transformation. Also is specified the design of the integration of the reservoir into the countryside by using riparian vegetation.
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Determination of floodplains and hydrotechnical assessment of Mastník water flow based on the DMR 5G data
Čápová, Pavlína ; Roub, Radek (advisor) ; Havlíček, Vojtěch (referee)
This work engages in the watercourse called Mastník. It focuses on the determination of flooded areas for couple of series (Q5, Q10, Q50, Q100) and hydro-technical assessment of particular objects. The chosen section is situated on cadastral area of town Sedlčany in the Central Bohemia region. Its length is 1.973 kms and there is located 5 water management objects reaching to the flow profile of the watercourse.
The data for this dissertation has been gained by the Czech State Administration of Land Surveying and Cadaster. It is about the digital relief of the 5th generation of aerial laser scanning. The laser rays are not capable of penetration the water surface, and thus describe the shape of the water-sources bed. So the tool called CroSolver was used to dig the water-sources bed. Then the hydrodynamic model has been created in program called HEC-RAS.
From the results of hydrodynamic model then was evaluated the real water-technical state of the object.
The outgoing data (dots defining the flood range to the surroundings) was after then inserted to the program ArcMap. Here the flood lines and from them the flood zones were created based on the particular series of the flows.
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Project of small water reservoir in the cadastral area of Milín.
Křivánek, Milan ; Havlíček, Vojtěch (advisor) ; Václav, Václav (referee)
This thesis deals with the design of a small water reservoir in the cadastral territory of local town Milin. The proposed reservoir will be multifunctional and its main purpose will be landscaping features. In addition, the reservoir will support biodiversity and will increase water supplies in the given area.
The reservoir is designed as a flow through and is inserted into the stream of the nameless brook. This brook is right tributary of the pond Kotalík. Basic parameters of the reservoir and other functional objects are designed, where all these have been verified by hydro-technical calculations. The project includes covering report, technical report and drawings.
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