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Characterization of poly(1,4-diethynylbenzene) by IGC method
Petrášová, Sabina ; Sedláček, Jan (advisor) ; Pacáková, Věra (referee)
Poly(1,4-diethynylbenzene) ( -conjugated polymer) was prepared as an insoluble polymer network via chain coordination polymerization of 1,4-diethynylbezene catalyzed with [Rh(NBD)acac] complex. Thermodynamic properties and acid-base characteristics of the prepared poly(1,4-diethynylbenzene) were studied by means of Inverse Gas Chromatography (IGC) in the temperature range 80-100 řC. Retention data of selected testing substances were used to determine the Gibbs energy of sorption, the sorption enthalpy and their acid-base and disperse parts as well as the disperse contribution to the surface energy and parameters of KA, KD, ANHPS and DNHPS quantifying the acid-base character of the studied polymer. The results showed that poly(1,4-diethynylbenzene) interacted more efficiently with Lewis bases than with Lewis acids. The values of experimental sorption enthalpy were used for the determination of the parameters KA and KD. Values of these parameters classify poly(1,4-diethynylbenzene) as the material with a slightly acid character. This conclusion is further supported by the results of H. P. Schreiber method based on the application of ANHPS and DNHPS parameters for the evaluation of the acid-base properties of the material. The infrared spectroscopy proved that poly(1,4-diethynylbenzene) contained...
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Deposited palladium catalysts for C-C bond forming reactions
Semler, Miloslav ; Štěpnička, Petr (advisor) ; Sedláček, Jan (referee)
Palladium based catalysts are widely used for C-C bonding reactions. This work describes the preparation of several such catalysts deposited onto siliceous, SBA-15 type support and common silica gel, whose surface was modified by organic chains with amine donor groups. The prepared catalysts have been tested in coupling reactions of organotin compounds and organic halides (Stille reactions) under various conditions.
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Study of molecular weight and configurational stability of substituted polyacetylenes
Trhlíková, Olga ; Sedláček, Jan (advisor) ; Netopilík, Miloš (referee) ; Žigon, Majda (referee)
3 ABSTRACT Complexes [Rh(cycloolefin)(acac)] (cycloolefin = norborna-2,5-diene, cycloocta- 1,5-diene and cyclooctatetraene) were investigated as catalysts of polymerization of monosubstituted acetylenes into stereoregular cis-transoid polyacetylenes. All complexes were highly active in arylacetylenes polymerizations in both coordinating and non-coordinating solvents. Selection of solvent and cycloolefin ligand of the catalyst allowed the control over polymer MW. The onset of initiation in the [Rh(cycloolefin)(acac)]/monomer systems proceeded as the proton transfer from the monomer molecule to the acac ligand under the release of acetylacetone and coordination of -C≡CR ligand to Rh(cycloolefin) moiety. Cis-transoid poly(phenylacetylene) and poly[(2,4-difluorophenyl)acetylene]s with required initial MW were prepared with these catalysts and submitted to the long-term ageing in which the polymers were exposed to the atmosphere and diffuse daylight either dissolved in tetrahydrofuran or in the solid state. Tightly connected processes of cis-to-trans isomerization of the polymer main-chains double bonds and oxidative degradation were found to proceed during polymers ageing in the solution. Besides, the formation of corresponding cyclotrimers accompanied the polymers ageing. However, the cyclotrimers amount was...
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The reaction of newspapers Severočeský deník and Reichenberger Zeitung on the foundation of the political party SDH W 1933
Sedláček, Jan ; Köpplová, Barbara (advisor) ; Bednařík, Petr (referee)
Diplomová práce "Reakce Severočeského deníku a Reichenberger Zeitung na založení Sudetendeutsche Heimatfront (Sudetoněmecká vlastenecká fronta) v roce 1933" v úvodní části představuje Sudetendeutsche Heimatfront, jsou přiblíženy okolnosti, které se týkaly jejího založení, a popsány události, které měly k jejímu založení úzký vztah. V další části popisuje práce společenskou situaci v Liberci v roce 1933. Ústřední, komparačněanalytická část práce porovnává podle předem stanovené metody články, které otiskly deníky Severočeský deník a Reichenberger Zeitung v období od 1. do 15. října 1933 v reakci na založení Sudetendeutsche Heimatfront Konradem Henleinem 1. října 1933.
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Porous polymer networks prepared from ethynylpyridines
Titlová, Štěpánka ; Sedláček, Jan (advisor) ; Sedláček, Ondřej (referee)
Series of new micro/mesoporous polymer networks with high content of pyridine segments was prepared. For the preparation were used ethynylpyridine type of monomers which were successfully homopolymerized and copolymerized with hydrocarbon diethynylarenes by chain-growth coordination polymerization catalyzed with [Rh(NBD)acac] complex. Polymerizations provided polyacetylene networks with main chains densely cross- linked by pyridine or arylene links. Prepared pyridine networks showed specific surface area SBET from 308 m2 /g to 923 m2 /g and variable content of pyridine segments in an interval from 3,27 mmol/g to 7,86 mmol/g. In networks, pyridine segments made part of interchain links or side groups. Networks with pyridine segments were successfully quaternized by heterogeneous postpolymerization reaction with bromoethane to form well covalently defined networks containing N-ethylpyridinium segments. Quaternized networks containing pyridinim segments in amount from 2,41 mmol/g to 4,24 mmol/g had preserved micro/mesoporous texture with values of SBET from 331 m2 /g to 592 m2 /g. Polyacetylene networks with N-ethylpyridinium segments were prepared also by catalyst-free (spontaneous) quaternization polymerization of diethylpyridines. These networks were worse covalently defined and had proved lower...
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Price Development of Apartments in Opava
Olbrechtová, Zuzana ; Sedláček, Jan (referee) ; Klika, Pavel (advisor)
This master’s thesis focuses on the price development of apartments in the central part of the city Opava. The introductory part defines the methodology of the apartment appraisal and the basic terms used in this topic. Further on, the database used in this thesis to achieve stated objectives is specified and evaluated. The Data are based on a documented purchase price of apartments, existing market value appraisal and ascertained assessed value. The development of purchase prices, market value and assessed value are being researched in the city of Opava. Furthermore, the development of the above-mentioned prices and values is researched in particular cadastral areas in the central part of Opava. The impact of aspects relating to apartment, building and locality are being evaluated. In conclusion, results of the local research are compared with the Czech Republic and selected countries of the European Union.
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