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Study of Thiophene Oligo-copolymers: Synthesis and Optoelectronic Properties
Krajčovič, Jozef ; Mazal,, Ctibor (referee) ; Kapička, Vratislav (referee) ; Friedl, Zdeněk (advisor)
Thesis presents synthesis and study of thiophene monomers, oligomers and polymers. The new series of thieno[3,4-b]pyrazine copolymers based on 3-dodecylthiophene and pyrazine monomers were prepared by oxidative polymerization with FeCl3. The effective synthetic method for preparation of 3-alkylthiophenes and thiophene oligomers was developed by optimizing of Kumada cross-couplig. The mentioned method could be realized for multikilos scale with possibility of transfer to pilot plant production. The second part of thesis focuses on synthesis and study of new thiophene compounds, which consist of both 2,3-diazo-1,3-butadiene bridge with two terminal chromophores and two thiophene units linked together via -position by pyrazine or hydrazine bridge. Finally, the new type of regular alternating copolymer consists of 2,2´:5´,2´´-terthiophene-5,5´-dicarboxylic acid (TEDA) and polyethyleneoxide (PEO) was prepared. Formation of polymer nano-subunits as separated phases in solid state was confirmed by TEM.
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Biomass as renewable energy resources
Přichystal, Lukáš ; Kizlink, Juraj (referee) ; Friedl, Zdeněk (advisor)
Bachelor’s thesis deals with an exploitation of a biomass as an energy carrier and the manners of obtaining this energy. Currently the most widely used methods of conversion of the biomass to various forms of energy, from burning to anaerobic digestion are described here. This work adverts to use the biomass not only in energetics, but also in the transport industry, as alternative fuel of vehicle engines. It describes not only the production of bioethanol from organic material, but also the techniques of hydrogen production as the fuel of future, and its use in fuel cells.
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Thermochemistry of high nitrogen heterocyclic compounds
Bartošková, Monika ; Pekař, Miloslav (referee) ; Friedl, Zdeněk (advisor)
The prediction of detonation properties of the new generation of high-nitrogen energetic materials (HNEM) is based on knowledge of their heats of formation, which are sum of values of particular nitrogen heterocyclic fragments. The diploma thesis describes theoretical calculations of heats of formation in gas phase ?f H°(298,g) for series of azines (number of N atoms 2-6) and azoles (number of N atoms 2-5) by means of quantum chemical methods. The semiempirical methods as PM3, DFT methods utilizing isodesmic approach and finally thermochemical G-recipes were used. All calculated values of heats of formation were scrutinized and for future application to HNEM materials the DFT B3LYP/cc-pVTZ method and thermochemical recipe T1 were recommended.
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Biotransformation of nitro aromates
Tomeček, Jaromír ; Bednařík, Karel (referee) ; Friedl, Zdeněk (advisor)
Contamination by nitroaromatic compounds, such as explosives, pesticides or other nitroaromatic compounds, is worldwide environmental problem. This text focuses on contamination by compounds from military and ammunition industry, most especially 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitro-1,3,5-triazinane (RDX) and 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX). First goal of this work is to provide the reader with a aerobic biodegradation and transformation processes of nitroaromatic compounds named above. The second goal is to compare the toxicity of initial nitroaromates and their transformation intermediates.
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Possibilities of waste glycerol reprocessing
Hýža, Bohumil ; Friedl, Zdeněk (referee) ; Kizlink, Juraj (advisor)
The aim of my bachelor thesis is to describe the possibilities of waste glycerol reprocessing. The thesis is purely theoretical and the information were obtained from various literary sources. Introduction of the study deals with the technological aspects of production of biodiesel by esterification of vegetable oils with methanol. Futhermore, there is described the amount of biodiesel produced in various countries around the world. In the theoretical part of the study are mentioned physical and chemical properties of glycerol and its traditional uses include the manufacture of nitroglycerin, the pharmaceutical use, etc. There are presented different technological methods for processing large quantities of glycerol too, such as steam reforming, which generates syngas which can be used for production of liquid fuels via Fischer-Tropsch synthesis. There is also desribed reduction of glycerol to propylene glycol with hydrogen. Other methods are dehydroxylation of glycerol to 1,3 - propanediol, halogenation of glycerol to produce epichlorohydrin, the catalytic dehydration of glycerol to acrolein and 3-hydroxy-propionic aldehyde, oxydehydration to polyacrylic acid, glycerol butylation over the Amberlyst catalyst and the formation of glycerol-tert-butyl ethers used as additives for fuels , polymerization of glycerol to polyglycerols, glycerol hydrothermal conversion to lactic acid catalyzed by alkali, esterification of carboxylic acids and glycerol to form glycerol esters, selective oxidation of glycerol to glyceric acid, tartronic acid and dihydroxyacetone, and glycerol as an additive for cement.
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Chirality and its importance in environmental organic analysis
Svobodová, Dagmar ; Friedl, Zdeněk (referee) ; Čáslavský, Josef (advisor)
This bachelor thesis is elaborated as literature search focused on the characterization of chirality and its importance for the environment. This work also gives review of the analytical methods and procedures aplicable for the chiral analysis of the organic pollutants. Obtained information showed that the importance of the chirality in the environmental chemistry is great. Individual enantiomers exhibit different toxicity and biological activity in the environment and therefore their monitoring by chiral analytical methods is essential.
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Environmental Aspects of Pyrotechnic Mixtures.
Mešková, Michala ; Bednařík, Karel (referee) ; Friedl, Zdeněk (advisor)
The submitted bachelor thesis deals with the study of pyrotechnic compositions and their influence on the health and environment. It explains the nature and ingredients used in pyrotechnic compositions. During burning these compositions release different compounds, toxic or non-toxic into the atmosphere in large quantities. In this work the issue of toxicity of selected alkali, alkaline earth metals and the other harmful metals was explored. The pyrotechnic compositions containing Ba, As, Pb and Cd were investigated in more detail. When burning the pyrotechnic compositions release noxious substances into the air first. Then these substances reach due to wet or dry transport mechanism the other components of the environment and mix with them. These compounds have diverse negative effects both on humans and the environment and other animals.
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