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Utilization of flow-coulometry in study of transport metal ions in humic gels
Kalina, Michal ; Pabst, Willi (referee) ; Klučáková, Martina (advisor)
This diploma thesis deals with the study of non-stationary diffusion of cupric ions in humic gels. The main objective of the work was the optimalization of conditions for using the electrochemical analyzer EcaFlow 150 GLP for the study of diffusion experiments. Next part was focused on reaching of constant concentration profiles of cupric ions in humic gel. Last aim of the study was the bond strength between cupric ions and humic acids. Diffusion was characterized by the values of the diffusion flux and cupric ions concentration profiles in humic gel. The data necessary for calculation were obtained by the electrochemical analyses of the extracts of each slice after diffusion on the EcaFlow 150 GLP. It has been proved that after application of several adjustment is this method suitable for the study of diffusion experiments. By using of different extraction agents was obtained the fractionalization of cupric ions according to the bond strength to humic acids.
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The issue of determination of tin in environmental matrices
Bušinová, Markéta ; Sommer, Lumír (referee) ; Doležalová Weissmannová, Helena (advisor)
This diploma thesis deals with the retrieval of the content of tin in environmental media, the circulation in them and possibilities of the determination of tin in the environment. Summarizes available information on the properties of tin and its compounds, the occurrence and circulation of tin in environmental and determination of tin in environmental media, attention is paid to the determination of total tin content using method of ET-AAS. The experimental part is focused on optimization methods of determination for the ET AAS and selection of a suitable extraction procedure for determination of total tin content in soils and sediments. The best procedure for the determination of tin in the ET-AAS was applied to samples of soil, sediment and water. As the optimum matrix modifier was chosen the solution of Pd (NO3)2 in 5% ascorbic acid, the optimum pyrolysis temperature was 1400 °C and atomization temperature 2400 ° C. Neither of extraction procedures examined were found to be an appropriate procedure for the determination of tin in environmental samples and further work is necessary to optimize the method of separation.
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Detection, Extraction and Measurement of the Length of the Metacarpal Bones in X-Rays of the Human Hand
Chalupnik, Alexandr ; Rydlo, Štěpán (referee) ; Drahanský, Martin (advisor)
The aim of the bachelor thesis is the design and implementation of an algorithm for the detection, extraction and measurement of the length of the metacarpal bones in x-rays of the human hand. The first part is focused on the principles of x-rays and the anatomy of the human hand. The second part contains the design and implementation of the task. The algorithm is based on image processing methods, such as thresholding or edge detection. In the end, the measurement results are evaluated on a set of images, which were provided by the Department of Anthropology at Masaryk University.
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Way of assign of stereoregularity of polypropylene
Hoza, Adam ; Tocháček, Jiří (referee) ; Kratochvíla, Jan (advisor)
The purpose of this work is to evaluate and compare isotactic index value determination of polypropylene homopolymer using extraction and solubility methods. A series of nine PP samples in a powder form specified by molecular weights in the range from 29 to 154 kg/mol was investigated. The methods afforded separation of polypropylene into two portions, the soluble fraction, and the insoluble one. Extractions were carried out in a modified Kumagawa extractor. Polypropylene extracts were obtained using several organic solvents (pentane, hexane, heptane, and octane) at their boiling points. Soluble fractions were obtained by dissolving the PP sample in high boiling point solvents (xylene, decahydronaphthalene, and 1,2,3,4-tetrahydronaphthalene) and cooling the polymer solution to 23°C. All the fractions were characterized using 13C-NMR, SEC, and DSC methods. Comparison of the extraction and solubility methods showed significant differences in the amount, stereochemical structure, molecular weight, and crystallinity of soluble, and insoluble fractions.
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Keyword Extraction from Scientific Articles
Kyjovský, Marek ; Schmidt, Marek (referee) ; Smrž, Pavel (advisor)
The main goal of this thesis is to explore basic methods which is using for extraction of important words from articles. After that try to understand character of using keywords from the available set of testing English articles. Based on these findings, try to design and to implement a system which is using this methods. Then created system testing on the real English articles and after that try to analyse results.
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Multiresidual methods for the determination of pesticides in waters
Matušková, Monika ; Kubíčková, Kristýna (referee) ; Vávrová, Milada (advisor)
This bachelor´s work of theoretical character deals with multiresidual determination of pesticides in water. It is especially focused on pesticides generating residues in surface water, which - due to their toxicity and persistence in environment - require goal-directed monitoring. The division of pesticides is stated, and their properties, toxicity and elimination process are described in the work. Furthermore, possibilities of analytical determination, especially the methods of gas and liquid chromatography are introduced here. In the last chapter, the complete analytic procedure for determination of organochlorine pesticides is described.
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Main Text Extraction from Web Documents
Mrózek, Daniel ; Burget, Radek (referee) ; Bartík, Vladimír (advisor)
This thesis deals with the main text extraction from the web documents in HTML format. It describes some methods that are already used and their separation. The goal of the practical part is to propose an algorithm for main text detection in HTML pages using primarily text features in combination with position features. Block classification is solved by multilayer perceptron. It also describes implementation of the proposed algorithm, the testing procedure and presentation of the obtained results.
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Acoustic signal classification
Pospíšil, Aleš ; Balík, Miroslav (referee) ; Atassi, Hicham (advisor)
Bachelor's thesis is focused on automatic music genre classication. First part of work evaluates present situation and refer to published studies. Gained knowledge from there is applied in this work. In terms of nding solution for problem the work summarize and describe suitable music features and classication techniques like neural networks and k-nearest neighbor. Four selected classication classes were classical, electro, jazz and rock music. Result of work is user-friendly system that provides automatic music genre recognition. Achieved classication performance is more less comparable to human music genres recognition.
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Preparation of hydrogels with the addition of grape pomace extract
Mojžíšek, Jan ; Veselá, Mária (referee) ; Kovalčík, Adriána (advisor)
The scope of this bachelor thesis is the preparation of hydrogels with antioxidant properties. These properties are achieved by the addition of grape pomace extract. The theoretical part of the thesis briefly summarizes the basic characteristics of the gels and describes the basic quantities in rheology. Furthermore, the classification, preparation and use of hydrogels are described. Attention is paid in particular to gels falling into the category of edible hydrogels. Information on antioxidants and matolins is also given. In the experimental part, extracts from grape pomace are characterized in terms of carbohydrate content, phenolic compounds and antioxidant properties. The extraction itself was carried out in different concentrated aqueous ethanol solutions. The extract with the highest total antioxidant activity, as determined by the ABTS method, was used for the preparation of the hydrogels. Agarose is used for the preparation of hydrogels. The change in the rheological properties of the hydrogels due to the addition of the prepared extracts was observed. The specific structures in the hydrogels were determined by FTIR.
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