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Alternative Powertrains and Fuels
Ondica, Rastislav ; Prokop, Aleš (referee) ; Dundálek, Radim (advisor)
This thesis explores different options about how to drive a vehicle, than using petrol and diesel. It discusess alternative fuels for combustion engines. It also explains hybrid and electric powertrains. It concentrates mostly on aspects such as ecology, costs, safety and the possibility of using those solutions.
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Diagnostics of plasma generated in mixtures of water and alcohols
Adámková, Barbora ; Slavíček, Pavel (referee) ; Kozáková, Zdenka (advisor)
This diploma thesis is aimed to the corona-like discharge in solutions of alcohols, specifically in ethanol, methanol, glycerol, butanol and isopropyl alcohol. The electric discharge was diagnosed by two methods. The first method was the measuring of electrical characteristics. Current-voltage characteristics were constructed from the measured average values of voltage and current. The breakdown voltages were determined from the current-voltage characteristics. The breakdown voltages of the individual alcohol solutions were dependent on the alcohol concentration, polarity of the electrodes in the reactor and solution conductivity. The breakdown voltage was determined for solutions of butanol, glycerol and isopropyl alcohol with a concentration of 20 vol. % and conductivity of 200 µS. The highest value of the breakdown voltage was determined for solution of glycerol at 580 V. The lowest voltage at which the discharge was observed was estimated for butanol (320 V), but due to the limited miscibility with water this value is inaccurate, and therefore in the second part of experiment butanol was not used. Alcohol series was supplemented with methanol. The second diagnostic method was the proton ionization mass spectrometry with the time of flight analyzer. The products formed in the reactor due to the plasma discharge were identified from the mass spectrum. Mostly, aliphatic hydrocarbons and their radicals were detected. The amount of products was observed in the dependence on the changing experimental conditions: alcohol concentration in the solution, the polarity of the electrodes in the reactor and the duration of the discharge. Only a small amount of compounds were detected in methanol. However, more molecules were formed with the increasing carbon chain in the alcohol molecule. More compounds were also detected with the increasing alcohol concentration and in case of the negative polarity of the main electrode. The formation of acetaldehyde as a typical discharge product was studied in details. Its production in time was observed and the reaction pathways of its formation in the ethanol solution were suggested.
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Detailed characterization of pyrolysis oil by separation techniques and mass spectrometry
Žvaková, Veronika ; Mravcová, Ludmila (referee) ; Čáslavský, Josef (advisor)
The aim of this work is detailed characterization of pyrolysis oil by advanced analytical separation methods and mass spectrometry. During the pyrolysis process decomposition of complex organic material take place in the presence of high temperatures and the absence of oxygen. Condensable part of vapours and aerosols forms viscous liquid called pyrolysis oil which is a complex mixture of large amount of compounds. In this work samples from microwave pyrolysis of woodchips and sewage sludge from wastewater treatment plant Brno-Modřice were analysed. Samples were provided by Bionic Laboratories company. Samples were separated by column chromatography on activated silica. For detailed characterization of each fraction gas chromatography with mass spectrometry detection and comprehensive two-dimensional gas chromatography with mass spectrometric detection with time of flight analyser were used. Substances that have been identified can be divided into several groups: alkanes, alkenes, aromatic hydrocarbons, polycyclic aromatic hydrocarbons, alcohols, aldehydes, esters, carboxylic acid and heterocycles.
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The influence of alcohols on the flow properties of sodium hyaluronate
Habartová, Lucie ; Pekař, Miloslav (referee) ; Smilek, Jiří (advisor)
This bachelor’s thesis examines the influence of alcohol presence on the conformation of sodium hyaluronate aqueous solutions primarily about the use of flow methods utilizing. Two molecule masses of sodium hyaluronan were studied, namely 1500-1750 kDa further referred to as high-molecular sodium hyaluronan and 500-750 kDa referred to as low-molecular. The flow and viscosity properties of high-molecular sodium hyaluronate have been studied in the presence of methanol, ethanol, isopropyl alcohol and terc-butanol in the concentration range 0-80 wt. %. Low-molecular sodium hyaluronate, and above all its flow and viscosity properties, were measured in the presence of ethanol and isopropyl alcohol in the concentration range 0-80 wt. %. Based on measured data, viscosities were assessed at infinitesimal stresses consistent with zero-rate viscosity. The high-molecular sodium hyaluronate ranged up to 327 mPas in terc-butanol solution. Viscosity values increased with the increasing length of the alcohol chain. The low-molecular sodium hyaluronate reached a maximum of 39 mPas in an isopropyl alcohol solution. The viscosity curves of low-molecular sodium hyaluronate were close to that of the Newtonian liquid.
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Stanovení vybraných obsahových látek ve vínech metodou kapalinové chromatografie
Hermanová, Veronika
This thesis deals with the analysis of wines using high-pressure liquid chromatography in order to analyze the content of alcohols, organic acids, and carbohydrates in wine. The most important groups and their representatives are presented in the literary review, as well as the theoretical basis of chromatographic methods, selected types of detectors, and used stationary and mobile phases. In the experimental part, analytical parameters of wines from the retail network, laboratory-prepared must and wines prepared by fermentation were measured using liquid chromatography methods with refractometric and UV detection. The results indicate the suitability of this combination of detectors for the selected wine analyses.
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Application of selected food industry wastes in the biotechnology of carotenogenic yeasts with a focus on optimizing yield coefficients.
Obračaj, Jan ; Němcová, Andrea (referee) ; Szotkowski, Martin (advisor)
This diploma thesis is focused on cultivation of selected carotenogenic yeasts on industrial waste substrates. These microorganisms are able to produce valuable metabolites with use in many industrial sectors, which primarily include pharmaceutical and food industries. Within this experiment, it was necessary to map the growth of these microorganisms on various alcohols and on other components of these waste substrates. Subsequently, the yield coefficients and amount of produced metabolites were compared, within the different strains and used source of nutrients. In theoretical part of the thesis are described used strains of yeasts, studied metabolites and their methods of extraction and analysis. The studied metabolites include carotenoid pigments, ubiquinone, ergosterol, microbial lipids and -glucans. The experimental part contains list of the equipment used, laboratory techniques, laboratory and analytical methods, chemicals, and list of the strains of microorganisms used. The result section then compares the amount of metabolites produced within the strain used and substrate used for cultivation, which took place both on a small scale and on a larger scale – fermentors. The results of this work can provide valuable information with application in industrial biotechnology of carotenogenic yeasts and reduce their economic demandingness and at the same time provide aid with ecological disposal of selected industrial wastes.
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QSAR Analysis of the Acute Toxicity Indices Determined by Alternative Methods
Kanásová, Mária ; Rucki, Marian (advisor) ; Dvořáková, Markéta (referee)
1 Abstract The goal of the thesis is to determine acute toxicity indices of seven alcohols (2-ethoxyethanol, 1-propanol, 3-methyl-1-butanol, 3-methyl-2-butanol, 3-hexanol, 2-methyl-3-hexanol, 1-nonanol) by two different alternative methods. Another goal is to create QSAR models to predict the acute toxicities of alcohols which belong into model limits. First of the methods used is based on the movement inhibition of lower animals Tubifex tubifex. The method provides the acute toxicity indices EC50. The second method uses the cell line of mouse fibroblasts called Balb/c 3T3 and it provides the acute toxicity indices IC50. The IC50 were recalculated to the LD50 values that correspond to the oral administration of alcohols to a rat. It has been found that 1-nonanol is included into the category of alcohols classified as acute oral toxic according to the EU CLP system. Other six alcohols are non-classified as acute oral toxic. Subsequently, accurate QSAR models has been created in order to predict the acute toxicity of other alcohols using Tubifex tubifex specie or Balb/c 3T3 cell line. The models are suitable for saturated, branched, ethoxy- and cyclic alcohols with the log POW value from −0.74 to 3.07. It was necessary to exclude the acute toxicity indices of 1-nonanol from these models as some solubility...
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Drama-Based Science Teaching
Scholzová, Veronika ; Teplý, Pavel (advisor) ; Janoušková, Svatava (referee)
The master thesis deals with Drama-Based Science Teaching. The theoretical part of the work deals with the literature research on the topic. It presents basic information about dramatization methods, sets straight the record on some common misconceptions and categorizes dramatization methods. Furthermore the fundamental role of plays and simulations in the learning is discussed. Research also provides evidence that dramatization methods can be and should be included in science teaching. They are suitable e.g. for the implementation of key competencies and teaching of Cross-Curricular Subjects as defined by The Framework Educational Programme (for Secondary General Education). Finally, specific examples of dramatization methods are shown, and the benefits and pitfalls of these methods are discussed. Practical part describes a dramatization teaching material created by the author. The topic is alcohols with a focus on pupils' understanding the formation of methanol and ethanol and the difference between these two. This material was tested on the sample of about 150 high school pupils in Prague. There is also author's solution as well as several pupils' worksheets included. The impact of the activity on the pupils' knowledge was measured and evaluated. The shortcomings of the original version were...
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The influence of alcohols on the flow properties of sodium hyaluronate
Habartová, Lucie ; Pekař, Miloslav (referee) ; Smilek, Jiří (advisor)
This bachelor’s thesis examines the influence of alcohol presence on the conformation of sodium hyaluronate aqueous solutions primarily about the use of flow methods utilizing. Two molecule masses of sodium hyaluronan were studied, namely 1500-1750 kDa further referred to as high-molecular sodium hyaluronan and 500-750 kDa referred to as low-molecular. The flow and viscosity properties of high-molecular sodium hyaluronate have been studied in the presence of methanol, ethanol, isopropyl alcohol and terc-butanol in the concentration range 0-80 wt. %. Low-molecular sodium hyaluronate, and above all its flow and viscosity properties, were measured in the presence of ethanol and isopropyl alcohol in the concentration range 0-80 wt. %. Based on measured data, viscosities were assessed at infinitesimal stresses consistent with zero-rate viscosity. The high-molecular sodium hyaluronate ranged up to 327 mPas in terc-butanol solution. Viscosity values increased with the increasing length of the alcohol chain. The low-molecular sodium hyaluronate reached a maximum of 39 mPas in an isopropyl alcohol solution. The viscosity curves of low-molecular sodium hyaluronate were close to that of the Newtonian liquid.
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Diagnostics of plasma generated in mixtures of water and alcohols
Adámková, Barbora ; Slavíček, Pavel (referee) ; Kozáková, Zdenka (advisor)
This diploma thesis is aimed to the corona-like discharge in solutions of alcohols, specifically in ethanol, methanol, glycerol, butanol and isopropyl alcohol. The electric discharge was diagnosed by two methods. The first method was the measuring of electrical characteristics. Current-voltage characteristics were constructed from the measured average values of voltage and current. The breakdown voltages were determined from the current-voltage characteristics. The breakdown voltages of the individual alcohol solutions were dependent on the alcohol concentration, polarity of the electrodes in the reactor and solution conductivity. The breakdown voltage was determined for solutions of butanol, glycerol and isopropyl alcohol with a concentration of 20 vol. % and conductivity of 200 µS. The highest value of the breakdown voltage was determined for solution of glycerol at 580 V. The lowest voltage at which the discharge was observed was estimated for butanol (320 V), but due to the limited miscibility with water this value is inaccurate, and therefore in the second part of experiment butanol was not used. Alcohol series was supplemented with methanol. The second diagnostic method was the proton ionization mass spectrometry with the time of flight analyzer. The products formed in the reactor due to the plasma discharge were identified from the mass spectrum. Mostly, aliphatic hydrocarbons and their radicals were detected. The amount of products was observed in the dependence on the changing experimental conditions: alcohol concentration in the solution, the polarity of the electrodes in the reactor and the duration of the discharge. Only a small amount of compounds were detected in methanol. However, more molecules were formed with the increasing carbon chain in the alcohol molecule. More compounds were also detected with the increasing alcohol concentration and in case of the negative polarity of the main electrode. The formation of acetaldehyde as a typical discharge product was studied in details. Its production in time was observed and the reaction pathways of its formation in the ethanol solution were suggested.
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