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Partial Oxidation of High-Boiling Hydrocarbon Mixtures on the Pilot Unit
Hanika, Jiří ; Lederer, J. ; Nečesaný, F. ; Nečesaný, F., jr. ; Poslední, W. ; Tukač, V. ; Veselý, Václav
The research on partial oxidation (POX) of high-boiling hydrocarbons with oxygen in the presence of water vapor was motivated to ensure increased demand on hydrogen, which is essential for a deeper hydrorefining of petroleum oils to ensure better quality of motor fuels. Experiments on improved pilot apparatus installed in Litvínov, UNIPETROL, a.s. have been implemented in cooperation the Institute of Inorganic Chemistry, a.s., Ústí n. l., Institute of Chemical Process Fundamentals AS CR, v. v. i., and Institute of Chemical Technology Prague. In the course of tests have been demonstrated good performance of the pilot plant unit and reproducibility of the experiment as well. A significant impact water vapor on the selectivity of the partial oxidation of high-boiling hydrocarbons with regard to the composition of the exhaust gas was detected in the study. Furthermore, it was stated that hydrogen content of the reaction product being during the partial oxidation of mixture of visbreaking distillate and residue, diluted with pyrolysis fuel oil reached 50 percent. Content of components in a gaseous product was in very good conformity with a synthesis gas composition produced by the plant unit of the UNIPETROL RPA Co., designed and build according to the license of the Shell Co.
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Mercury and its Future in the Czech Republic
Navrátil, Tomáš ; Vytopilová, M. ; Vlčková, Š. ; Mrázová, K. ; Zakharov, S. ; Honsová, Š. ; Pelclová, D.
Toxicity of mercury has been discussed for many years by specialists as well as by laymen. Legislative tools connected with measures and conditions concerning the trade, manufacture, use and interim storage of mercury, mercury compounds, mixtures, mercury-added products and the management of mercury waste are currently being prepared. Some suggestions and prepared measurements are mentioned and discussed in this contribution. Of course, it is necessary to differentiate among various forms of it, i.e., metallic form, vapors, amalgams, soluble and insoluble inorganic and organic compounds.

Development of Composite Mortar and Cement Mixtures
Hlavinková, Eva ; Gemrich, Jan (referee) ; Fridrichová, Marcela (advisor)
This diploma thesis deals with the design of composition and the study of properties of the ternary binding system based on purposeful ettringite formation, which was subsequently used for the preparation of self-leveling floor materials, specifically self-levelling underlay and thin-layer floor screed. In the designed compositions of the mixtures is then focused attention on optimizing the dosage of two kinds of plasticizer agents, followed by assessing their impact on the technological properties of these materials.

Magnetic particles as analytical tool in medicine
Gablech, Evelína ; Pekárková, Jana (referee) ; Hubálek, Jaromír (advisor)
This work reports on knowledge of magnetic nanoparticles, modification of their surface and their using in different areas. Literature review describes using MNPs in separation techniques of analytic biochemistry to imobilizate nucleic acids and proteins. The matter of experimental part is synthesis of MNPs using coprecipitation of iron salts and next modification of their surface. In MNPs preparation the effect of the presence of PEG in the reaction mixture and the temperature effect on the resulting properties of MNPs was examined. MNPs surface was modified by two different methods, emulsion polymerization method with precursors MMA and AAc, and carboxylation method using 11 -mercaptoundecanoic acid. PEG or temperature had little effect on the properties of the prepared MNPs. Establishing carboxyl groups succeeded only when the method of emulsion polymerization was used.

Influence of Organic Electrolytes Presence on Swelling of Nafion Membrane in Methanol-Water Mixtures
Randová, A. ; Hovorka, Š. ; Izák, Pavel ; Bartovská, L.
The anisotropic swelling of Nafion 112 foil in methanol - water - inorganic salt was examined. Our results show that even small addition of inorganic salt into methanol - water mixture affects kinetics as well as the swelling equilibrium. The effect of inorganic salts LiCl, NaCl, KCl, CsCl, CaCl2, CdCl2, K2CO3, KNO3, NH4Cl, and AgNO3 was studied. Swelling kinetics of Nafion in ternary mixtures including salt show maximum suggesting that effect of methanol-water is faster but effect of inorganic salt is stronger. Theexperimental data, presented in this work allow us to assume that swelling of Nafion decreases with increasing ionic radius of cation.

Production of polyhydroxyalkanoates employing Haloferax mediterranei
Hlináková, Kristýna ; Kučera, Dan (referee) ; Obruča, Stanislav (advisor)
This bachelor thesis is focused on study of selected effects on production of both polyhydroxyalkanoates (PHA) and extracellular polysaccharides (EPS) by halophile Archae Haloferax mediterranei. Theoretical part deals with a brief characterization of biopolymers and provides overwiev of the relevant microbial producers. The experimental part is focused on selection of a suitable substrate, concentration of sodium chloride and glucose in culture medium for a optimal production of biopolymers. Effects of light and suitable cultivation temperature were studied as well. UV-VIS spectrophotometry and gravimetry were used for analysis of biomas content. The content of PHA was analysed by gas chromatography with FID detection. PHA produced by H. mediterranei is a copolymer P(3HB-co-3HV), 3HV content is about 10%. The mixture of glucose and glycerol proved to be the most suitable substrate for a production of PHA, with a content od 80,6% of PHA. Further, we investigated optimal concetration of NaCl, which was found at 200 g/l. Interestingly, microbial culture responded to various salt concertations by differences in pigment formation. Finally, the last parameter optimalized in this work was temperature of cultivation. The highest content of PHA was obtained at 37°C, but the culture was capable of PHA accumulation and growing also at 50°C.

Electrophoretic separations of saccharides in short capillary.
Vochyánová, Blanka ; Opekar, František (advisor) ; Jelínek, Ivan (referee)
A new laboratory system has been developed for rapid electrophoretic separations and determinations of inorganic and organic ions. The instrument employs short fused silica capillary in combination with contactless conductivity detection. The basic functions of the apparatus have been tested using mixture of inorganic ions. It has further been applied to separations of neutral mono- and disaccharides. The model mixture contains five saccharides (sucrose, lactose, glucose, fructose and ribose). The technique developed has been used to determine sucrose, glucose and fructose in high-energy drinks.

Cr(VI) adsorption to synthetic mixture of soil minerals
Pehová, Edita ; Veselská, Veronika (advisor) ; Tomáš, Tomáš (referee)
Due to its toxicity, the Cr(VI) is known as a substance with negative effects on the environment. Understanding of Cr mobility, speciation and its toxicity helps to prevent negative impacts of this contaminant in soils, natural waters and atmosphere. This diploma thesis deals with a mechanism of Cr(VI) adsorption on to mixture of selected soil minerals as quartz, kaolinite and ferrihydrite based on mineralogical and chemical composition of the real contaminated soil. Main goal of diploma thesis is to test the selected surface complexation model, the DLM (diffuse layer model), which could be able to capture the process of Cr(VI) adsorption in natural heterogenic systems like soils. Component additivity approach (CA) was tested. The adsorption experiments were performed with three different concentrations of Cr(VI) (10-4, 10-5, 10-6) as a function of pH at different ionic strengths. Obtained data were used for modelling of adsorption edges and for DLM testing. Results confirmed, that Cr(VI) adsorption in synthetic mixture of enlarged soil minerals, is controlled mainly by presence of Fe-(oxy)hydroxides. The mechanistic surface complexation models used for modelling of Cr(VI) adsorption onto synthetic mineral mixtures, based on real mixed ratios of representative mineral phases in soils, can be useful for prediction of processes responsible for transport and retention of the Cr(VI) in soils.

Filling materials for vertical and horizontal constructions using renewable raw materials
Gregor, Petr ; Vacula, Miroslav (referee) ; Bydžovský, Jiří (advisor)
This thesis deals with industrial hemp and its use in vertical and horizontal structures. The work is mainly focused on the fillers of industrial hemp and inorganic binder. In the practical part of the feasibility study for future use of industrial hemp in the construction industry as a filling materiál in vertical and horizontal structures. This area has been targeted by all test samples. They are presented here and evaluated and compared the results of tests on unconfined compressive strength, compressive strength, depending on the deformation density of fresh and hardened mixture and the termal conductivity of different types of inorganic binders and fillers such as hemp.

The proposal of acceptable fluoride salts mixtures for PuF.sub.3./sub. and higher actinides transmuter
Valenta, Václav
The selection of fluorides salts of type Li-Be-Na/F with acceptable properties for actinides transmuter, where is operated in interval temperature 600-700.sup.o./sup.C, is mentioned in this work. Solubility of tri-fluorides XF.sub.3./sub. in individual fluoride salts mixture from temperature 550-700.sup.o./sup.C and thermo-physical properties (melting temperature, density, thermal expansibility, kinematic viscosity, heat capacity, thermal conductivity) for salts without fuel part and with fuel part with 3% mole of TRUF.sub.3./sub.(trifluorides of Pu, higher actinides and fission product) are showed.