|
| |
|
|
Effect of pH on quantitative determination of additives in nanofibers
Grufíková, Jana ; Marek, Pokorný (referee) ; Knotková,, Kateřina (advisor)
The object of my thesis was to prepare a nanofiber layer with dye additives and to quantify the additive content in dependence on pH. The nanofiber layers with additives were prepared by means of electrospinning. The analysis of the additive content in samples was performed by UV-VIS spectrophotometry. Concretely Erythrosine, Eriochrome Black, Riboflavin and Brilliant Blue were analysed. Each of this colors has different chemical structure and charge. The pH was defined by use of buffers, namely acetate buffer (pH 5), phosphate buffer (pH 7,4) and carbonate buffer (pH 10). For Erythrosine and Eriochrome Black the research was extended to study the effect of ionic strength on the quantitative determination of these dyes. It was found that the quantity of the determined additive depends on the pH and also on the ionic strength. However, this dependency is different for each additive. This confirms the assumption of influenced chemical structure and charge by interaction with polymers and buffers used in this experiment. The accuracy of evaluation is influenced by the way of data processing.
|
|
| |
|
|
Research on the Preparation of Masonry Mortars
Koláček, Tomáš ; Dvořák, Karel (referee) ; Gazdič, Dominik (advisor)
This thesis deals with development in the preparation of masonry mortars. The theoretical part focuses on basic knowledge of mortars, individual types of mortar, preparation methods and individual components from which the mortar is composed. The practical part deals with the proposed reference and modified mortar mixtures and compares their technological properties.
|
|
|
Monitoring of the wheat quality for food production
Slavíčková, Radka ; Hýsková, Eva (referee) ; Omelková, Jiřina (advisor)
The aim of this study was to monitor the quality of wheat Triticum aestivum, imported into the laboratory MORAGRO after harvest by eight different suppliers, and to evaluate the main quality parameters decisive for the final use of cereal crops. The introduction of the theoretical part was devoted to understanding commercial and agricultural importance of wheat and description of morphological and physiological characteristics of wheat grain. The core of the theoretical part has been focused on the description and explanation of physical and chemical properties of the wheat grain, which largely affect the final product quality of wheat. External factors affecting final quality and yields of wheat were also commented. The experimental part was based on measurements of main quality parameters of wheat (moisture content, bulk density, falling number, amount of gluten and the wheat proteins, sedimentation value and content of additives and impurities). In most cases, measurements were carried out using automated instruments. The quality of wheat was determined based on the obtained results, which allows deciding, whether it is appropriating for food production.
|
|
|
New electrode structures for alkaline accumulators
Fusek, Petr ; Novák, Vítězslav (referee) ; Vrbický, Jiří (advisor)
Master´s thesis is focused on development of electrodes used in alcaline accumulators, by using new kinds of materials and compounds. Basic possitive eletrode was made of nickel, on this electrode were applied new layers of Ni(OH)2 by using the method called electrodeposition. For electrodeposition was used solution with Ni(NO3)2 in diverse concentrations. Later on, this material was enriched with aluminium admixtures to increase stability of alfa modification in Ni(OH)2. These concentrations were measured and analysed in diagrams. For measurement was used device Biologic. The diagrams were commented with recommendations for production use in accumulators.
|
|
| |
|
|
Analysis of filler types onto the wood plastics composites
Blaha, Lukáš ; Pospíšil,, Ladislav (referee) ; Vaněrek, Jan (advisor)
Wood polymer composite (WPC) is a material that combines the wood material and the thermoplastic matrix. As filler to be used as wood flour and thermoplastic matrix will be used in primary or recycled polypropylene. WPC will be made by injection molding. The aim of the thesis is to find the optimal ratio between primary and recycled polymer in which the result will be the best physical and mechanical properties.
|
|
|
Lubrication of combustion engines in 21st century
Súkeník, Juraj ; Nevrlý, Josef (referee) ; Křupka, Ivan (advisor)
Lubrication is inseparable part of internal combustion engines. It primary influences operation, lifetime and efficiency of internal combustion engine. This bachelor`s thesis summarizes present state and future view of internal combustion engine lubrication. The work deals with tribology of several engines sections and composition of present lubricants for internal combustion engines.
|
|
|
An overview of industrial oils
Ondrouch, Dušan ; Ficza, Ildikó (referee) ; Šperka, Petr (advisor)
Methods of production of base oils and their branching are described in the introduction of the thesis. Essential properties, which are the prime aspect of diversification of particular oils, are described in the following part. Commonly used additives, which adjust properties of base oils, are outlined thereafter. The last part of the thesis deals with industrial applications and requirements, which are set for particular application.
|
guest ::
