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Polymer nanocomposites with PMMA matrix
Kostková, Jana ; Žídek, Jan (referee) ; Jančář, Josef (advisor)
This bachelor thesis deals with s study of mechanical and viscoelastic properties of nanocomposites with PMMA matrix filled with different types of surface-modified silica, which differed by the specific surface area, surface treatment and particle size. Nanocomposites were prepared by dissolving, where nanofillers were injected into the dissolved matrix. Nanocomposite samples were tested in tensil and viscoelastic properties were determined till the softening point by dynamic-mechanical analysis (DMA). All types of nanofillers had almost no effect on tensile modulus of nanocomposites at room temperature (it was not reduced) one type of silica at a content 2 %, which was also confirmed by the DMA. The temperature DMA measurements showed that samples containing 2 % of silica were generally thermally more stable compared with nanocomposites containing 1 % of silica. Storage modulus of nanocomposites, except two ones, were similar or lower such pure PMMA to temperature 66 C, then the trend reversed. Loss modulus of all samples was one order of magnitude lower then the elastic modulus.
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Properties comparison of two products used for skating rink based on ehtylene-propylene-dien rubber
Kostková, Jana ; Kučera, František (referee) ; Bálková, Radka (advisor)
This master thesis deals with characterization of two black and white products based on ethylene-propylene-diene rubber (EPDM) used for skating rink. Products marked with A and are different in their diameter of circular tubes trough which cooling medium passes and also in the distance of these tubes. Both of materials were characterized in order to determine whether it is the EPDM and how are they different. The characterization methods were used: differential scanning calorimetry, thermogravimetric analysis, attenuated total reflectance Fourier transform infrared spectroscopy, tensile test, swelling test, thermooxidative test. The composition of both materials, including fillers and others additives is almost the same but difference is in structure of EPDM and probably also in interaction with fillers, what exhibits different mechanical properties, thermooxidative stability and thermal capacity. These differences which have been found are essential for long-term use properties of both materials.
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Discrete Surface Fairing
Matýsková, Martina ; Kostková, Jana (advisor) ; Suk, Tomáš (referee)
This thesis proposes a new method for fairing of surfaces, which are represented by a triangulated mesh. Motivation for our task is a 3D reconstruction, which results in a triangulated mesh. Such mesh is typically corrupted by noise (due to data and processing inaccuracy), which is required to be faired out. We solve the problem on a discrete surface, where two criteria for optimization are defined: surface curvature and non-uniformity. The curvature deals with surface smoothness, while the non-uniformity with surface regularity. The problem of fairing is solved by a discrete diffusion. Since our aim is to fair surfaces with boundaries, first we describe the fairing of curves, then fairing of closed urfaces, and finally fairing of surfaces with boundary (which is in fact a combination of the former ones). We have tested the algorithm's performance on synthetic as well as real data with good results. The experiments showed that our proposed algorithm is robust, stable and does not shrink an object, while its main surface characteristics are preserved.
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Nemoci králíků a jejich prevence
Kostková, Jana
This Bachelor thesis with topic of Rabbit Diseases and Prevention starts with the history of rabbit domestication, brief description of its anatomy and its taxonomic rank. Its main focus was to descript the most substantial viral, bacterial, parasitic and gastrointestinal diseases, which appear the most in domestic breeding. As significant viral diseases we have chosen myxomatosis and rabbit plague. Chosen bacterial diseases are pasteurellosis, rabbit rhinitis, colibacillosis and rabbit spirochetosis. Coccidiosis and Toxoplasmosis were selected among parasitic diseases. For every disease, characteristic, etiology, pathogenesis, symptomatology, diagnostic and prevention were listed. The end of the thesis was dedicated to prevention of disease, breeding hygiene and sanitation.
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Discrete Surface Fairing
Matýsková, Martina ; Kostková, Jana (advisor) ; Suk, Tomáš (referee)
This thesis proposes a new method for fairing of surfaces, which are represented by a triangulated mesh. Motivation for our task is a 3D reconstruction, which results in a triangulated mesh. Such mesh is typically corrupted by noise (due to data and processing inaccuracy), which is required to be faired out. We solve the problem on a discrete surface, where two criteria for optimization are defined: surface curvature and non-uniformity. The curvature deals with surface smoothness, while the non-uniformity with surface regularity. The problem of fairing is solved by a discrete diffusion. Since our aim is to fair surfaces with boundaries, first we describe the fairing of curves, then fairing of closed urfaces, and finally fairing of surfaces with boundary (which is in fact a combination of the former ones). We have tested the algorithm's performance on synthetic as well as real data with good results. The experiments showed that our proposed algorithm is robust, stable and does not shrink an object, while its main surface characteristics are preserved.
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Properties comparison of two products used for skating rink based on ehtylene-propylene-dien rubber
Kostková, Jana ; Kučera, František (referee) ; Bálková, Radka (advisor)
This master thesis deals with characterization of two black and white products based on ethylene-propylene-diene rubber (EPDM) used for skating rink. Products marked with A and are different in their diameter of circular tubes trough which cooling medium passes and also in the distance of these tubes. Both of materials were characterized in order to determine whether it is the EPDM and how are they different. The characterization methods were used: differential scanning calorimetry, thermogravimetric analysis, attenuated total reflectance Fourier transform infrared spectroscopy, tensile test, swelling test, thermooxidative test. The composition of both materials, including fillers and others additives is almost the same but difference is in structure of EPDM and probably also in interaction with fillers, what exhibits different mechanical properties, thermooxidative stability and thermal capacity. These differences which have been found are essential for long-term use properties of both materials.
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Polymer nanocomposites with PMMA matrix
Kostková, Jana ; Žídek, Jan (referee) ; Jančář, Josef (advisor)
This bachelor thesis deals with s study of mechanical and viscoelastic properties of nanocomposites with PMMA matrix filled with different types of surface-modified silica, which differed by the specific surface area, surface treatment and particle size. Nanocomposites were prepared by dissolving, where nanofillers were injected into the dissolved matrix. Nanocomposite samples were tested in tensil and viscoelastic properties were determined till the softening point by dynamic-mechanical analysis (DMA). All types of nanofillers had almost no effect on tensile modulus of nanocomposites at room temperature (it was not reduced) one type of silica at a content 2 %, which was also confirmed by the DMA. The temperature DMA measurements showed that samples containing 2 % of silica were generally thermally more stable compared with nanocomposites containing 1 % of silica. Storage modulus of nanocomposites, except two ones, were similar or lower such pure PMMA to temperature 66 C, then the trend reversed. Loss modulus of all samples was one order of magnitude lower then the elastic modulus.
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