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Preparation and properties of building blocks of specialty polymers
Šichová, Kristýna
This Diploma Thesis presents results obtained by solution of two partial projects: a) Preparation of monomers from renewable sources using metathesis and tandem hydrogenation catalyzed with ruthenium compounds - project solved during my Erasmus stay at the Université de Rennes 1 in France; b) Preparation and properties of ,-bis(tpy)quarterthiophene oligomers carrying ionic side groups as oligomonomers for polyelectrolyte conjugated dynamers - project solved at the Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague. Project a): Self-metathesis of 1,2-epoxyhex-5-ene (but-3-enyloxirane) and its cross-metathesis with methyl acrylate and acrylonitrile catalyzed with ruthenium compounds as well as tandem design of these metatheses and consecutive hydrogenation of their products by gaseous hydrogen have been optimized. The following influences have been studied and tuned: (i) type of the catalyst (Grubbs, Hoveyda, Zhan) and its concentration and method of dosing, (ii) concentration of reactants and additives, (iii) type of solvent, and (iv) reaction temperature. Reactions were monitored by the GC, GC and MS methods and the products were characterized by the NMR method. Methyl 6,7-epoxyheptanoate (methyl 5-oxiranylpentanoate) obtained by the tandem...
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Preparation and properties of building blocks of specialty polymers
Šichová, Kristýna ; Svoboda, Jan (advisor) ; Sedláček, Jan (referee)
This Diploma Thesis presents results obtained by solution of two partial projects: a) Preparation of monomers from renewable sources using metathesis and tandem hydrogenation catalyzed with ruthenium compounds - project solved during my Erasmus stay at the Université de Rennes 1 in France; b) Preparation and properties of ,-bis(tpy)quarterthiophene oligomers carrying ionic side groups as oligomonomers for polyelectrolyte conjugated dynamers - project solved at the Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague. Project a): Self-metathesis of 1,2-epoxyhex-5-ene (but-3-enyloxirane) and its cross-metathesis with methyl acrylate and acrylonitrile catalyzed with ruthenium compounds as well as tandem design of these metatheses and consecutive hydrogenation of their products by gaseous hydrogen have been optimized. The following influences have been studied and tuned: (i) type of the catalyst (Grubbs, Hoveyda, Zhan) and its concentration and method of dosing, (ii) concentration of reactants and additives, (iii) type of solvent, and (iv) reaction temperature. Reactions were monitored by the GC, GC and MS methods and the products were characterized by the NMR method. Methyl 6,7-epoxyheptanoate (methyl 5-oxiranylpentanoate) obtained by the tandem...
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Structure and magnetic properties of f-electron compounds and their hydrides
Mašková, Silvie ; Havela, Ladislav (advisor) ; Kamarád, Jiří (referee) ; Reiffers, Marián (referee)
Title: Structure and magnetic properties of f-electron compounds and their hydrides Author: Silvie Mašková Department: Deparment of Condensed Matter Physics Supervisor: Doc. RNDr. Ladislav Havela, CSc., Deparment of Condensed Matter Physics, Faculty of Mathematics and Physics, Charles University, Prague, The Czech Republic Abstract: Magnetic properties were studied in several types of actinide- and lanthanide-based ternary compounds. We have shown indirect that anisotropy of compressibility and thermal expansion can be related to the direction of magnetic moments at U-compounds with "soft" directions (where the closest U-U links are) perpendicular to the moments direction. Comparison of U and RE compounds of the 2-2-1 type indicates that contrary to U compounds, RE compounds can absorb much more hydrogen. The involvement of the f-states in metallic bond, which takes place at actinides and not in lanthanides, makes the U-based compounds apparently more stable against hydrogenation. Basic electronic properties were established for ζ -Pu19Os, which is a close analogy to β-Pu, and for its low-temperature variety η -Pu19Os. The results confirm that the volume is not the main parameter driving Pu properties, as β-Pu with intermediate volume is the most strongly correlated Pu phase. Keywords: uranium compounds,...
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Selective hydrogenation/Oxidation of CVD graphene using AFM
Přikryl, Vojtěch ; Švarc, Vojtěch (referee) ; Bartošík, Miroslav (advisor)
Graphene is a perspective material for utilization in electronics due to its high charge carrier mobility. However, in order to be applicable in practice the bandgap opening is necessary. One way of achieving this is modification of graphene by hydrogenation or oxidation. This work concerns the possibility of using AFM for local hydrogenation/oxidation of graphene depending on the bias voltage between the tip and the sample. The presence of hydrogenation/oxidation was examined by Kelvin probe force microscopy and Raman spectroscopy. The possibility of oxidation was proved but hydrogenation was not proved.
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Preparation of organocatalysts derived from monosaccharides
Nekvinda, Jan ; Veselý, Jan (advisor) ; Trnka, Tomáš (referee)
This bachelor thesis is focused on the synthesis of organocatalysts derived from monosaccharides, in particular D-glucose and D-glucosamine, with various protecting groups. Synthesis of various thiourea catalysts and the attempt to prepare new squaramide catalysts is described. ABSTRAKT Tato bakalářská práce je zaměřena na syntézu organokatalyzátorů odvozených od monosacharidů, zejména z D-glukózy a D-glukosaminu, s různými chránícími skupinami. Dále je popsána syntéza různých thiomočovinových katalyzátorů a pokus o přípravu katalyzátoru obsahující derivát kyseliny čtvercové.
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Induced Oscillatory Behaviour During 2-Methylpropene (Isobutene) Hydrogenation in a Packed Bed Microreactor.
Vajglová, Zuzana ; Stavárek, Petr ; Jiřičný, Vladimír ; Kolena, J.
This contribution focuses on the induced oscillatory behaviour observed during the continuous hydrogenation of 2MP in a packed bed microreactor. Induced reproducible oscillations have been studied using the on-line gas chromatograph (GC-FID/TCD) and a catalyst bed temperature monitoring. Effects of the temperature, thermal conductivity and space velocity on the properties of induced oscillations have been investigated in detail. The study results revealed extremely high sensitivity of the oscillatory behaviour to the heat transfer conditions in the system. Experimental tests focusing on the space velocity effect revealed a significant influence on the oscillation amplitude height and period phase length with the high reaction rate. Based on the character of the induced oscillations, they have been classified as thermo-kinetic oscillations1 as they are resulting from the interaction between the exothermic reaction, heat transfer and a reversible decrease in the catalyst activity.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22016111814300 - PDF
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The optimization the production of selected medicinal substances
Fránek, Jan ; Ing.Oldrřich Smékal (referee) ; Omelková, Jiřina (advisor)
Mgr. Jan Fránek 2011: The optimization the production of selected medicinal substances The diploma thesis dealt with optimization of production of fingolimod by hydrogenation. During the optimization of production, there was reduction of benzylic hydroxygroup and nitrogroup of nitrofingotriol. Reduction of two different groups caused dividing process of hydrogenation into two phases. The original intention was to optimize production only in the autoclave, but the need of using acidic catalytical medium in first phase led to dividing the production into reduction in the reactor and following catalyzed hydrogenation, already in neutral conditions, in the autoclave. The way of preparation of active substance by using an autoclave had not been explored in detail before. Evaluation of optimization is a part of results. There are also production charges on pilot plant included in results. Because the results of procedure of the pilot unit were not uniform, it was necessary to continue in optimization even after finishing the production in pilot plant. Following procedure modified according to the latest experiments was passed to the operating process.
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