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Microrheology with Fluorescence Correlation Spectroscopy
Kábrtová, Petra ; Sedláček, Petr (referee) ; Mondek, Jakub (advisor)
A comparison of three passive microrheological techniques was made with the emphasis on FCS. Fluorescently labelled and unlabelled polystyrene particles were used to probe a microrheological response of glycerol solutions, Mili-Q water and sodium hyaluronate solutions. In addition, for FCS technique an approximated equation for calculation of MSD values was derived and verified. It was found that FCS outmatches current microrheological techniques of DLS and video-based particle tracking by its ability to gain a broader data range including the area in which, until now, it was impossible to describe a microrheological behaviour of samples reliably.
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Potential use of waste lipid substrates and glycerol to production of carotenoids by yeasts
Kostovová, Iveta ; Obruča, Stanislav (referee) ; Márová, Ivana (advisor)
The aim of this study was use of lipid waste substrates and waste glycerol as carbon sources for red yeasts. Six yeast strains, namely Rhodotorula glutinis, Rhodotorula rubra, Rhodotorula aurantiaca, Cystofilobasidium capitatum, Sporobolomyces roseus and Sporobolomyces shibatanus were used for cultivation. All studied yeast strains were able to utilize glycerol and rapeseed oil as a carbon source. Cultivation in oil medium was in most of strains accompanied by decreased production of carotenoids. Increased production of ergosterol, lycopene and biomass was observed in some strains only. Most of yeast strains cultivated in glycerol medium produced increased amount of biomass as well as carotenoids. The best producer of bi-omass and pigments was yeast strain Sporobolomyces roseus CCY 19-6-4 grown in medium containing glucose and glycerol in a 1:1 ratio.
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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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Non - freezing heat transfer liquids on the polyol platform
Solný, Tomáš ; Čáslavský, Josef (referee) ; Kotlík, Josef (advisor)
This diploma thesis is focused on the evaluation of changes in non-freezing heat transfer liquid composed of mixture of polyols and water, used in the real solar thermic system. On the base of the research a new heat transfer liquid is proposed on the platform of 1,3-polyols. The emphasis is put on the non-toxic properties of such system revealing the two chemical candidates for a new heat transfer liquid: 1,3-propanediol and glycerol. These chemicals are mixed together with water using different volume concentrations and properties of such liquids are evaluated.
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Production of carotenoids grown on waste fat
Holub, Jiří ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
Carotenoids are lipid-soluble pigments which are contained in plants and microorganisms. Carotenoids are known for their antioxidant effects. Lipids are predominantly non-polar substances, which are essential and present in all types of organisms. The research was made by theoretical and practical form. It was dealing with production of carotenoids pigments and different lipophilic substances by yeasts of Rhodotorula glutinis, Rhodosporidium toruloides and Sporidiobolus metaroseus, cultivated in media containing waste fat or glycerol. Further, methods for obtaining lipid substances from microorganisms and with further analysis of samples by gas or liquid chromatography were optimized. The main task of the research was to find out which types of media and yeasts are the most suitable for production of lipid substances. For production of lipid substances in glycerol media, as the best producing strain Rhodosporidium toruloides was found, which simultaneously reported the highest concentrations of carotenoids on fatty and fatty hydrolyzed media.
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The Influence of Nanoparticles on The Properties of Hard Polyurethane Foams
Eliáš, Filip ; Kotlík, Josef (referee) ; Petrůj, Jaroslav (advisor)
The theoretical part of the thesis focuses on general principles of polyurethane chemistry. Nanotechnologies are also discussed, in particular using nanoparticles in the production of polyurethane foams. There are also mentioned selected preparation methods of silver and titanium dioxide nanoparticles. The experimental part describes mainly a novel method for synthesis of the concentrated solution of titanium dioxide nanoparticles in glycerol and their analysis by using confocal microscopy, scanning electron microscopy, dynamic light scattering and UV-VIS spectroscopy. Finally, there are suggested particular steps for further investigation of prepared nanoparticles for the production of rigid polyurethane foams, and also for other applications.
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Dielectric Relaxation Spectroscopy of Glycerol
Stráník, Rostislav ; Liedermann, Karel (advisor)
This doctoral thesis deals with the analysis of dielectric spectra of glycerol with dielectric relaxation spectroscopy (DRS). Dielectric spectra of glycerol have been measured in the frequency range 20 Hz to 10 MHz and in the temperature range 10 K to 300 K. The observed dielectric spectra featured a typical relaxation maximum, which could be in the first approximation described by the Arrhenius equation. The activation energy of the relaxation process observed was 90 MJ/kmol. The relaxation strength as well as the shape of the relaxation peak remained in the temperature interval 180 K - 230 K (visibility of peak) almost the same, thus indicating that no change of the relaxation mechanism comes about. Much attention was in the thesis paid to the analysis of the excess component of the relaxation alfa process, in the literature commonly denoted as "excess wing". The thesis puts forward a procedure for the quantification of the magnitude of the excess wing. The excess wing magnitude thus determined turns out to increase monotonously with increasing temperature. The excess wing is here interpreted as a manifestation of a weakly-pronounced beta relaxation.
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Use of starch and glycerin in polymer films with controlled life span
Almásyová, Zuzana ; Pospíšil, Ladislav (referee) ; Jančář, Josef (advisor)
This diploma thesis deals with preparation and testing of biodegradable materials for use in the packaging indrustry. The task of this work is to prepare set of laboratory made films based on wheat starch, glycerol, polyvinyl alcohol with the addition of a suitable additive, which has been selected as citric acid. A suitable composition meeting the requirements of the packaging foils has been found. Quaternary blends from all components achieve the best results. It has been found that citric acid can influence the chemical structure and thus affect the mechanical and thermal properities and also the degree of solubility. The films were characterized in terms of mechanical properities by tensile testing and thermal stability by means of thermogravimetric analysis with respect to the phase structure. The structure was characterized by Fourier transform infrared spectroscopy and confocal laser scanning microscopy. The biodegradability of the film was tested by its solubility in aqueous medium.
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Waste Recycling Possibilities of Rigid PU Foams from the Production of KingSpan CZ
Figalla, Silvestr ; Kučera, František (referee) ; Petrůj, Jaroslav (advisor)
The theoretical part of the bachelor thesis evaluates methods and trends of recycling polyurethane materials with the emphasis on rigid polyurethane foams used as thermo isolation building material. The experimental part is focused on glycerol process verification as an alcoholization agent in the regenerative process of polyol, together with perspective microwave heating of reaction mixture. The final part of the work suggests further steps in the development of above mentioned process with the aim of its transforming into technical practice.
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