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The effect of reaction conditions and type of active sites on the kinetics of heterogeneously catalysed formylation of amines
Olšovská, Adéla ; Veselý, Ondřej (advisor) ; Kubička, David (referee)
Formamides are valuable compounds in pharmaceutical production and organic synthesis; however, their common synthesis methods suffer from number of drawbacks including low reaction rate and contamination with heavy metals leached from a catalyst. According to several articles, these problems could be overcome by using zeolite-based catalysts. Nevertheless, the mentioned articles provide somewhat conflicting results and also lack a clear description of which centres in zeolites are catalytic active. Therefore, we prepared a set of zeolite-based catalysts commonly described in the literature (zeolite Beta ion exchanged to H+ and Cu2+ form) in order to test them as catalysts and clarify their catalytic behaviour and nature of the active sites. We chose formylation of N-methylaniline by formic acid as the model reaction for our research and performed a series of experiments under varying conditions (solvents, concentration of reactants, temperature). In contrast to the published articles, none of the investigated materials demonstrated significant catalytic activity in our experiments. Moreover, we found that the often pronounced catalyst: zeolite Beta ion-exchanged into the copper form, is unstable in the presence of formic acid, which causes leaching of copper into the reaction mixture. At the same...
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Preparation of hierarchical zeolites for fine chemical synthesis
Veselý, Ondřej ; Eliášová, Pavla (advisor) ; Přech, Jan (referee)
Preparation of hierarchical zeolites for fine chemical synthesis Author: Bc. Ondřej Veselý Supervisor: Mgr. Pavla Eliášová, Ph.D. Prague, 2019 Abstract (in english): The thesis is focused on synthesis of hierarchical (micro-mesoporous) zeolites by several different methods and their application in catalytic reactions. Performance of hierarchical materials prepared by different approaches has been investigated, as well as the effect of framework topology and type of acidity on the outcome of the reactions. The work was elaborated in the Department of Physical and Macromolecular Chemistry of Charles University under the supervision of Mgr. Pavla Eliášová, Ph. D. The work is divided into three parts. In the first part several methods of preparation of hierarchical zeolites have been investigated and compared in catalytic reactions. Desilication, selective removal of silicon from the framework, is a post-synthetic method that can be used to introduce additional mesoporosity into a zeolite. The process leads to formation of mesopores by introducing defects into the zeolite structure. The resulting mesopore size is very broad. To partially control the pore size, alkylammonium cations may be added to the solution to protect the crystal surface. The desilication was performed on MTW zeolite which contains...
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Machining of hardened steels
Veselý, Ondřej ; Osička, Karel (referee) ; Jaroš, Aleš (advisor)
Diploma thesis on Machining hardened steels is focused on the analysis of longitudinal turning of hardened steel 14 109 by using a tool from PKNB in terms of measuring the force load using a dynamometer and then evaluating the surface quality. The theoretical part deals with the issue of turning technology, cutting materials and heat treatment of steel. In the practical part, the influence of cutting conditions on the resulting values was assessed during the experiment. Twelve samples with different combinations of cutting conditions were tested, then was selected a sample that met the criterion of combining minimum cutting forces values and surface quality. The experiment shows that force load values can be achieved twice less by combining cutting conditions with an appropriate combination.
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Technological design of shaft production
Veselý, Ondřej ; Fiala, Zdeněk (referee) ; Kalivoda, Milan (advisor)
Bachelor thesis on Technological design of shaft production deals with machining processes in order to realization of production in the conditions of series production, based on the drawing of the part, when the appropriate material and semi-finished product is gradually determined following technological process. This is assigned to suitable machines and tools, the technical economic evaluation related to the production process is carried out. In conclusion it will be used CAD/CAM technology, the prototype component will be made on CNC machine using Edgecam software.
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The Apartment block Novolisenska
Veselý, Ondřej ; Erben, Adam (referee) ; Pavlovský, Tomáš (advisor) ; Šuhajda, Karel (advisor)
This bachelor thesis deals with the design of a new "viladum" (a smaller apartment building with a higher standard of living) in Brno Líšeň. The work is based on a previously developed architectural study developed within the course AG32. "Viladum" usually referres to as older urban villas, which have been converted to host more housing units. Today this is a very comfortable and desirable form of housing. The topic of the thesis was to create a design of a smaller apartment house, typologically emerging from the "viladum". The proposed building has one underground and three above-ground floors. Each of the above floors contains one dwelling unit. The proposal uses the height difference on the site to create a ramp for vehicles in the basement where garages are located. The volume and location of the house on the parcel is mainly based on the limits given by the development plan. The house was deliberately designed with a higher standard of living. From the elevator you can enter directly into the apartments. The ground floor apartment is completed with a garden, an apartment on the third floor, southwest oriented to the terrace. The south and east side of the apartments are illuminated by French windows and balconies. The building meets the requirements for low-energy buildings according to ČSN 73 0540-2: 2011. The basement consists of a monolithic reinforced concrete structure made of waterproof concrete on the principle of "white bathub". Above-ground floors are made of porous concrete blocks combined with monolithic reinforced concrete ceilings. The roof is designed as a green roof.
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Preparation of hierarchical zeolites for fine chemical synthesis
Veselý, Ondřej ; Eliášová, Pavla (advisor) ; Přech, Jan (referee)
Preparation of hierarchical zeolites for fine chemical synthesis Author: Bc. Ondřej Veselý Supervisor: Mgr. Pavla Eliášová, Ph.D. Prague, 2019 Abstract (in english): The thesis is focused on synthesis of hierarchical (micro-mesoporous) zeolites by several different methods and their application in catalytic reactions. Performance of hierarchical materials prepared by different approaches has been investigated, as well as the effect of framework topology and type of acidity on the outcome of the reactions. The work was elaborated in the Department of Physical and Macromolecular Chemistry of Charles University under the supervision of Mgr. Pavla Eliášová, Ph. D. The work is divided into three parts. In the first part several methods of preparation of hierarchical zeolites have been investigated and compared in catalytic reactions. Desilication, selective removal of silicon from the framework, is a post-synthetic method that can be used to introduce additional mesoporosity into a zeolite. The process leads to formation of mesopores by introducing defects into the zeolite structure. The resulting mesopore size is very broad. To partially control the pore size, alkylammonium cations may be added to the solution to protect the crystal surface. The desilication was performed on MTW zeolite which contains...
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Utilization of the Relationship between German, English and Czech in Teaching German as a Foreign Language
Veselý, Ondřej ; Lobenstein-Reichmann, Anja (advisor) ; Zeman, Dalibor (referee)
The thesis examines the utilization of linguogenetic (Proto-Indo-European) and cultural- historic (through borrowing) relationships among European languages in instruction and self- study of foreign languages, and as a means of strengthening European unity. As an example serves German, English and Czech, occasionally Latin and Old Greek, in Teaching German as a Foreign Language. The methods are secondary sources research (to present concise history of the languages and their ancestral proto-languages), analysis of linguistic relationships (between 450 lexemes of the German basic vocabulary and their semantic equivalents - translations - in English, Czech, occasionally Latin and Old Greek) and an opinion survey (among 75 respondents about their interest in the historiolinguistic approach and about their belief in this improving the international relations). The results showed that more than a half of the 450 German words are linguogenetically cognate to English and a significant amount of them also to Czech and Latin. On the contrary, borrowings did not play such an important role within the basic wordstock. Most respondents expressed some kind of interest into the historiolinguistic approach and many of them also believed this approach to have a positive impact on intercultural aspects. KEY WORDS...
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