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Computer Modelling of Macromolecules
Khirnova, Oleksandra ; Uhlík, Filip (advisor) ; Jirsák, Jan (referee)
In the present work we study diffusion of linear and cyclic polymers. We run simulations using Brownian dynamics in θ-solvent and good solvent with several hydrodynamic models. Obtained results were compared with existing theories. In the present work we study diffusion of linear and cyclic polymers. We run simulations using Brownian dynamics in θ-solvent and good solvent with several hydrodynamic models. Obtained results were compared with existing theories. In the present work we study diffusion of linear and cyclic polymers. We run simulations using Brownian dynamics in θ-solvent and good solvent with several hydrodynamic models. Obtained results were compared with existing theories. In the present work we study diffusion of linear and cyclic polymers. We run simulations using Brownian dynamics in θ-solvent and good solvent with several hydrodynamic models. Obtained results were compared with existing theories. In the present work we study diffusion of linear and cyclic polymers. We run simulations using Brownian dynamics in θ-solvent and good solvent with several hydrodynamic models. Obtained results were compared with existing theories.
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Effect of polymers on the physical properties of waterworks sludge
Svěrák, Michal ; Benešová, Libuše (advisor) ; Vašek, Petr (referee)
Water treatment sludge disposal has been an important issue for decades. The actual system of sludge treatment is still not satisfying. The whole area is mainly focused on sludge volume reduction - dewatering. Sludge dewatering efficiency is based on many factors. Most important are the quality of raw water, technology of water treatment and sludge storage system. Two laboratory methods are used for measuring sludge dewatering ratio - capillary suction time (CST) and specific resistance to filtration (SRF). As a dewatering method filtration is mostly used, but centrifugation and clarification are also popular. The latest trend in sludge dewatering is usage of polymers, which improves and supports the dewatering of sludge. Dewatered and thickened sludge can be used as a secondary material or disposed at dumps.
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Study of various materials for solar cells-
Růžička, Aleš ; Toušková, Jana (advisor) ; Prokeš, Jan (referee)
Sluneční články jsou slibnou a rozvíjející se alternativou ke klasickým zdroj·m elektrické energie. V této práci studujeme r·zné parametry křemíkových a organických slunečních článk·. Ze získa- ných temných voltampérových charakteristik křemíkového článku naměřených při více teplotách byl určen mechanismus transportu náboje v porovnání s teoretickými modely. Taktéž u organické vrstvy polymeru P3CT byl z temné voltampérové charakteristiky za pokojové teploty navržen me- chanismus transportu náboje. Pro měření voltampérových charakteristik slunečních článk· za osvětlení byl použit simulátor slunečního záření. Z naměřených osvětlených voltampérových charakteristik byly určeny výstupní parametry křemíkových a organických slunečních článk·, přičemž byl kladen d·raz na účinnost přeměny sluneční energie na energii elektrickou. Zjištěná účinnost křemíkového článku byla η = 13, 21% a maximální účinnost organických článk· byla η = 1, 51%.
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Selection and development of educational materials for high school support webpage www.studiumchemie.cz
Zaspalová, Jana ; Šmejkal, Petr (advisor) ; Petrželová, Simona (referee)
This diploma thesis deals with selection, design and creation of new education materials for high school teacher supporting webpage www.studiumchemie.cz. The selection of the proper theme was done on the basis of research and evaluation of recent materials on the mentioned webpage and materials created at the Department of chemical education of Faculty of Science of Charles University in Prague. Preliminarily, the themes of synthetic macromolecular materials and new materials were selected. The convenience of the selected themes was confirmed by research and evaluation concerned to the preliminarily selected theme of recent high school textbooks and webpages. Consequently, educational materials in the form of PowerPoint presentations, websites, worksheets, tests, games and experiments focused on the themes of synthetic macromolecular substances and new materials were created. Materials were processed in accordance with the Framework Education Programme for Secondary General Education (Grammar Schools) as well as in accordance with the requirements of the Catalogue of graduation exam requirements from chemistry. The PowerPoint presentation and the webpage on synthetic macromolecular materials were roughly evaluated by group of teachers and the results of the evaluation are also part of the thesis....
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Počítačové modelování větvených polymerů
Preisler, Zdeněk ; Uhlík, Filip (advisor) ; Netopilík, Miloš (referee)
In this work we study properties of branched polymers in a good solvent. We focus on problematic related to the size exclusion chromatography and predicting elution behavior of randomly branched polymers. We developed a software for generating self-avoiding walks (SAW) of any given non-looping architecture on a cubic lattice using Monte Carlo (MC) simulation and vali- date its reliability by presenting the scaling of different architectures: linear, 3-arm star and 6-arm star and asymmetric star. We calculate distribu- tion coefficients and calibration curves for size exclusion chromatography for various architectures to validate that the hydrodynamic radius is more suitable for predicting elution volume than the radius of gyration. Then we propose a new method for, although approximate, a very fast estimation of radius of gyration and hydrodynamic radius for different architecture using a graph method. It is done by comparing MC results with results obtained from graph theory. Then we introduce a correction to graph-theory results to fit the MC. At the end we present depletion layer calculation from MC and self-consistent field (SCF) method for polymers and their comparison. We show how calculation of depletion layer using SCF can be improved to get significantly better agreement with MC results. v
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Assessment of degradation of coatings for cement composites with organic fillers due to aggressive environments
Pernicová, Kateřina ; Vacula, Miroslav (referee) ; Bydžovský, Jiří (advisor)
There are many methods and techniques for assessing the degradation rate of coatings for cement composites with organic fillers. However, it is necessary to choose appropriate combination of various adverse conditions including intensity level of corrosive media and duration of action of these compounds on the material to simulate their complex effect in relation to the real exposure of structures. Part of the theoretical work is focused on the kinds of coatings that are suitable for cement composites with organic fillers and then there are listed devaluing environments which these coatings affect. There is also a proposal for a testing a complex simulation of a real environment. The practical part describes the tests that were performed on cement bonded particleboards with applied coatings.
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Electrical properties analysis of epoxy resins with various fillers
Horák, Luděk ; Kazelle, Jiří (referee) ; Frk, Martin (advisor)
Presented bachelor thesis is focused on studying electroinsulating epoxy resin-based sealings. It describes the chemical composition, production, properties and measuring methods of basic electric quantities of these materials. This work also embodies a preparation of composite epoxy resin samples with different kinds of micro-ground siliceous sand as a filling. The samples given are measured on the temperature dependency of relative permitivity, dissipation factor and inner resistivity.
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Recyclation of Plastics
Lasota, Ondřej ; Němec, Karel (referee) ; Molliková, Eva (advisor)
Plastic materials thanks to their properties like strength, durability, versatility and relatively low cost has gained this much popularity. With their constantly increasing amounts contribute to the waste. Most frequent method of waste disposal is landfill, which is due to plastic’s durability undesirable and causes serious problem for the environment. This bachelor thesis focuses on the use of secondary raw materials obtained from polymer waste. Large amounts of generated polymer waste can be appropriately designed methods processed to produce fuel, to modify asphalt mix and to reinforce concrete. Different methods are analyzed and their advantages and disadvantages are shown.
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Machining of polymericMaterials
Ondráček, Ivo ; Němec, Karel (referee) ; Molliková, Eva (advisor)
This bachelor’s thesis deals with the machining of polymeric materials and the major differences between the machining of metals and polymers or plastics. Introduction describes the basic elements in the history of the discovery and use of plastics. The thesis focuses on the basic division, further definitions and internal structure of the polymers. There are also discussed the most widely used machining technology and requirements for tools and materials. At the end of the work we are specified properties and selected types of plastic materials intended for processing. Practical informations were obtained during the visit to Brno company Belt Plast, Ltd.
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Degradation test of polymer material
Darebný, Tomáš ; Špinka, Jiří (referee) ; Vaněk, Jiří (advisor)
Basic knowledge of photovoltaic energy transformation, devices and materials, used in photovoltaics are summarized in this bachelor’s thesis. Sort of degradation factors of the photovoltaic panels and the norm ČSN EN 61215, are described there. The main purpose of this research is monitoring the change of volume and surface resistivity of selected covering materials. These covering materials were influenced of increased humidity.
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