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Modeling of anisotropic viscoelastic fluids
Šípka, Martin ; Tůma, Karel (advisor) ; Průša, Vít (referee)
In this thesis, we aim to create a framework for the derivation of thermodynamically consistent anisotropic viscoelastic models. As an example we propose simple models extending the isotropic Oldroyd-B and Giesekus models to illustrate the models' behavior and the process of finding the correct equations. We show what behavior in sheer we can expect and continue with a 3D simulation inspired by the experiment on a real liquid crystal mixture. Finally, we compare the simulation and the experiment to find similarities and possible further research topics.
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Modeling of anisotropic viscoelastic fluids
Šípka, Martin ; Tůma, Karel (advisor) ; Průša, Vít (referee)
In this thesis, we aim to create a framework for the derivation of thermodynamically consistent anisotropic viscoelastic models. As an example we propose simple models extending the isotropic Oldroyd-B and Giesekus models to illustrate the models' behavior and the process of finding the correct equations. We show what behavior in sheer we can expect and continue with a 3D simulation inspired by the experiment on a real liquid crystal mixture. Finally, we compare the simulation and the experiment to find similarities and possible further research topics.
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Elemental analysis of the flat display devices for urban mining
Štípek, Radek ; Strnad, Ladislav (advisor) ; Mihaljevič, Martin (referee)
aaaaaRare earth elements (Sc, Y and group 15 lanthanides) and their compounds currently have significant practical use in metallurgy, glass industry, as highly active catalysts for the production of so-called. NiMH batteries, alloys for the manufacture of permanent magnets and e.g. moderators rods in the nuclear energy, but above all they have an irreplaceable role in modern electronics for phosphors TV screens, CRT earlier today, PDP and LCD monitors and displays, tablets, mobile phones etc., which give them a high-quality picture and sound. Unlike most base and precious metals are concentrated in the conquerable ore deposits, occur in the form of compounds as part of mixed minerals in the rarely economically exploitable concentrations, a mining and processing is costly and negative impacts on the environment, paradoxically towards the title but their overall content in the crust is relatively high, the average concentration in the range of about 150 to 220 ppm. The main world producer of REE, China, in 2010, significantly reduced exports by 40 %, making prices of some REE increased up to 1500 % during the month. Demand for REE is growing, so often talks about the recycling of valuable materials back into production, as called. "Urban mining", ie "urban mining", thereby reducing the amount of...
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Transport systems used in cosmetics
Škopová, Jitka ; Kramářová,, Daniela (referee) ; Zemanová, Jana (advisor)
Between transport systems in cosmetics belong liposomes, liquid crystals and also chosen substances, which speed under given conditions a transport of active compounds, so-called accelerators of trans-dermal penetration. Liposomes are used topically (i.e. directly onto the place of their action in surface structures of organism) in dermatological and cosmetic preparations, they facilitate the penetration of active substances into the deeper layers of the skin and make possible their more expressive treatment. Some properties of liquid crystals are similar to the properties of live organisms. Analogous to the vital cells are they sensitive to light, sound, warm, mechanical straining and chemical changes. And by contraries, some scientists mark vital cells as liquid crystals. Thanks to this similarity are liquid crystals characterized by their excellent ability to penetrate by the skin, which is probably comparable only with liposomes. Accelerators of trans-dermal penetration otherwise accelerators of penetration by the skin are substances, which change structure of the skin or derma to be more permeable for other compounds. The trans-dermal penetration of active substances is an important part of medical researches. Those results are however applied also in other branches as for example is cosmetic industry. From the point of view of the chemical texture of these materials form they a very heterogeneous group and an elucidating of mechanisms of their incidence is so far rather in beginnings.
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