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Problems of phenols in water
Tylichová, Petra ; Čáslavský, Josef (referee) ; Doležalová Weissmannová, Helena (advisor)
This bachelor`s thesis deals with the issue of phenols in the waters. The theoretical part summarises the information about the characteristics of the phenols, its use, appearance in the environment, and its effects on human health. There are described methods of determination these substance in the waters. The last chapter disserts on possible methods of eliminating the phenols from the aqueous environment with special attention paid to the adsorption method. Part of this thesis is also dedicated to the chlorinated phenols which originate from chlorination of the phenolic waters and which cause the sensory interferences of the waters. The experimental part of this thesis is dedicated to removing the phenol from a model water through the adsorption into a powdery active carbon Norit SA SUPER.
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Determination of organic substances in tar formed after biomass combustion and gasification
Hájek, Radek ; Mravcová, Ludmila (referee) ; Vávrová, Milada (advisor)
Biomass pyrolysis and gasification techniques count among basic technological procedures for its use as a source of energy. As a side-effect, production of tar can be considered. Tar is a complex mixture of various organic compounds and affects negatively both the environment and the facilities where biomass is processed. Within the scope of this master thesis the analysis of tar samples from different materials was performed. As an appropriate analytical method the gas chromatography combined with flame ionization detection (GC-FID) and time-of-flight mass spectrometry (GC-TOF-MS) was chosen. The concentrations of volatile organic compounds known as BTEX, polycyclic aromatic hydrocarbons (PAH) and phenolic compounds were assessed.
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Effect of species composition change of forests on the quality of litter and derived soil organic matter
Roblíková, Věra ; Jandová, Kateřina (advisor) ; Bartuška, Martin (referee)
Climate change will alter the species composition of forests, which will cause changes in litter amounts and quality and potentially affect the carbon content and its stability in forest soils. With the knowledge of inputs to the biogeochemical carbon cycle, we can design methods of forest management and effectively mitigate climate change with forest cover. The aim of this thesis is to summarize information about i) change in species composition of temperate forests in Europe and the Czech Republic, ii) differences in litter amount and quality, iii) effect of litter quality on the stability of carbon in soils. I propose a master's thesis with an observational and experimental investigation of forest species change's effect on carbon content in soils. Climate change will shift species ranges northward and to higher altitudes. While species do not differ in the production of above-ground litter, they differ in the quality of above-ground litter and the quantity and quality of below-ground litter. The rate of decomposition is affected by the litter quality of tree species. Through their effect on the fauna, tree species affect the amount of carbon stored in the mineral horizon. However, the effect of litter quality on carbon stability in mineral horizons is unknown, in terms of both the density fractions of...
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The influence of the surface pretreatment of boron doped diamond electrodes on electrochemical oxidation of phenol and its derivatives
Hnízdilová, Lucie ; Schwarzová, Karolina (advisor) ; Nesměrák, Karel (referee)
The aim of this thesis is the study of electrochemical oxidation of para-substituted phenol derivates using cyclic voltammetry (CV) and ,,direct current" voltammetry (DCV) on boron-doped diamond electrode (BDD) and comparison with some analogous meta-substituted compounds. Among the studied substances were p-cresol, 4-methoxyphenol, 4-hydroxybenzoic acid, 3-(4-hydroxyphenyl)propionic acid, 4-nitrophenol, 4-chlorophenol and 3-(trifluoromethyl)phenol. The oxidation of the analytes was performed in an acidic (pH 2,0) and basic (pH 11,0) Britton-Robinson buffer on mechanically polished, oxidated and hydrogenated surfaces. Another subject of the thesis is to analyze the influence of different substituents, characterized by the Hammett constant, on the oxidation potential of selected phenols. They are oxidized at more positive redox potentials in acidic media, than in basic media, where they are dissociated. The oxidation on the polished and hydrogenated surfaces were similar, whereas were shifted to higher values on the oxidated surface. Further, the signal intensity decreased on the oxidated one, and the oxidation of phenols was not recognizable in basic media. The passivation of the electrode was less significant in pH 2,0 buffer. The best result of Hammett correlation was achieved on a polished and...
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Modifikace barvy dřeva nanočásticemi železa
Kmoníčková, Petra
This thesis clarifies the influence of the content of polyphenolic substances on the color change of oak and larch wood after the modification of surface by iron. The samples were modified by solution of iron nanoparticles at two different concentrations. After that the change of color components was determined. The analysis of polyphenols by Folin-Ciocalteu by spectrophotometric method was made for each sample and also dry matter in the extracts was determined. The final data were subjected to statistical analysis and correlation and regression analysis were performed. Statistically significant correlations for both species were found.
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Vliv kvasinkové kultury na aromatický profil bílých vín
Fráňová, Anna
The Diploma thesis deals with the topic of yeasts culture and its influence on aromatic profile of white wines. The first part of the thesis focuses on literature overview, where we can find more details about wine yeasts and its species. The main focus is on possibilities of reproduction these yeasts. The result can be seen on growth curve, which shows the speed and intensity of multiplication of the yeasts. We will see the proces of alcoholic fermentation and determine the difference between spontaneuos fermentation and controled fermentation using special active dry wine yeasts. Smoothly going to second part of literature overview, where we can learn about aromatic properties of wines, especially the aromatic profile that is typical for variety Grüner Veltliner. The beginning of the experimental part will familiarize us with brief description of variety Grüner Veltliner, that were used for the experiment and its origin. Then we can see clear diagram describing the proces of the experiment following the analysis of analytic parametrs. The parametrs are concered about the stum and description of the proces of fermentation of partial variations. In the result part we can find analytical of resultant wines from spectrophotometric apparatuses ALPHA and MIURA and the results of senzoric evaluation done by committee of seven degustators. The final part of the thesis is about comparison of results within discussion and final results listed in the chapter conclusion.
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Vliv geologických a půdních podmínek na kvalitativní parametry vín
Kupsa, Jan
Aim of this thesis was to answer question how big is influence of geological and pedological conditions on qualitative parameters of wines. Four sites with variety Ryzlink rýnský have been choosen on vineyard Velká Vendule in Velké Žernoseky based on differect pedological a geological characteristics. Site have been closely described from pedological point of view. Wine samples from vintages 2012 to 2014 have been made from every site via unified vinification so 51 wine properities could be measured. Results have undergone canonical diskriminant analysis. It was found content of elements in soil isn't in clear relation to content in wine, mainly because different climatic conditions each year. In spite of this it was possible to clearly separate all wine samples by sites by chossing selected parameters (D/H)II, 13C, B, Ca, K, Mg, P, catechin a trans-piceid. They could be therefore called markers for tracking wine authenticity in relation to geological and pedological conditions.
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Vliv vybraných stanovištních faktorů na proteolytickou aktivitu lesních půd s důrazem na organické a anorganické látky
Holík, Ladislav
PhD thesis focuses on soil biochemistry, namely the effects of organic and inorganic substances on proteolytic ktivity in forest soils. The thesis is composed of several impacted journal articles and two manuscripts. Selected organic compounds feature L- and D-tartaric acid, phenolics, proteinogenic and non-proteinogenic amino acids, auxins and cytokinins, whilst inorganic substances are represented by salts. Furthermore, an article dealing with the effects of different forest management practises on soil enzymatic ktivity (including proteases) is adjoined. Its aim is to monitor the effect of forest regenerative elements (forest stand gaps) on enzymatic ktivity, whereas the intervention into forest ktivity changes the moisture and thermal conditions of the site. The results show that out of the organic substances tested L- and D-tartaric acid, proteinogenic and non-proteinogenic amino acids and auxins have a positive effect on the proteolytic ktivity. Conversely, phenols and cytokinins acted as inhibitors. Soil salinization also had a negative effect on proteolytic ktivity of forest soils. The Influence of forest management through forest regenerative elements on soil protease ktivity was not detected. Potential urease ktivity was the only enzyme that reacted to the change of climatic conditions of forest habitat; however, ktiv not a principal topic of this work.
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Možnosti vinifikácie fortifikovaného vína
Hanúsek, Martin
The diploma thesis deals with the possibilities of vinification of fortified wine. In the literary part, it deals with the history of the production of fortified wines and describes their basic types. In addition, it explains the individual methods of spirit adding, selection of distillate and conditions for production in Slovakia and the Czech Republic. At the end of the literary section, individual groups of phenolic compounds are described as important compounds contained in fortified wines. In the experimental part, an attempt is made for the Alibernet variety. It was fortified in the beginning, in the middle and at the end of the alcoholic fermentation in two series - must and mash. Complete phenolic substances, titratable acids and pH were measured over three months. The resulting wines were sensitized. All the results were statistically processed and the practice recommendation was then drawn.
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Stanovení flavonoidů ve vybraném sortimentu rodu Iris L. a možnosti jejich použití jako rostlinných barviv
Valešová, Barbora
The thesis deals with the determination of the content of substances in the rhizomes and flowers of the selected variety of the genus Iris L. and the possibilities of using the iris as a dyeing plant. The literary part of the diploma thesis deals with the characteristics of the selected species and its cultivars of the genus Iris L., a description of species important in phytotherapy. Furthermore, the description of phenolic substances, flavonoids, anthocyanins, antioxidant capacities and methods of determination of these substances are described. In the practical part, the described methods are applied, the results are compared and statistical data evaluated. In the flowers of the iris, phenols, flavonoids, antioxidant capacity and anthocyanins were determined. The rhizomes determined phenols, flavonoids and antioxidant capacity. The diploma thesis also partially follows the bachelor's thesis, which compares the results of the color scale for individual samples of substances. In the diploma thesis we used to stabilize the character of metal salts (these salts in BP were not used). Several variants of the dyeing bath were used for dyeing. The filter extract of flowers in combination with vinegar, Salt, salt, edible soda, and blue rock were sampled by cold and boiling in both ways for 30 and 60 minutes. The samples were soaked in Soil Solution No. 1, which included 5 different substances (Soda, Savo, Salt, Vinegar, and Blue Scalp) and No. 2 (Blue Scalp, Vinegar and Water). As a control, samples were used that passed only the color bath without additives or pre-soaking.
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