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Machinable bioceramic foams prepared by gelcasting method
Šťastný, Přemysl ; Částková, Klára (referee) ; Trunec, Martin (advisor)
Diploma thesis is focused on development of method for preparation individualized bioscaffolds prepared by milling of HA foam prepared by gel casting method and consolidated via epoxy curing reaction. Diploma thesis continues in bachelor thesis Modern processing methods of porous bioceramics. Literature search is filled in the newest knowledge from the field of bioactivity enhancement of scaffolds. Experimental part of diploma thesis described development of system for individualized scaffold manufacturing from HA suspension preparation, preparation of ceramic blocks used as material for machining to final blocks machining. Pressure strength of foam were evaluated, too. Chosen samples were coated with calcium polyphosphate coating for biological response enhancement. Coated samples were given for in-vivo test to partner university in Beijing under the terms of project FP7-NMP-2013-EU-China: "Bioscaffolds"
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Electrospinning of polyvinylidenfluoride based fibers
Hošek, František ; Šťastný, Přemysl (referee) ; Částková, Klára (advisor)
Electrospinning is one of the rapidly developing methods for obtaining fibers of very small thickness. There is a wide-scale use of nanofibers, and it has a great potential in many fields, such as in medicine, biology, chemistry, electronics, environmental protection, energy-harvesting, and other. Polyvinylidene fluoride (PVDF) appears to be a promising material for fiber production for its excellent mechanical and chemical properties. It is a chemically inert substance, very resistant to thermal stress. The aim of this bachelor thesis is the preparation of PVDF fibers by electrospinning and the study of the influence of three different surfactants on the spinnability of PVDF, on the arrangement and the shape of fibers which are formed during electrospinning. The effect of surfactant concentration (1 wt%; 0.5 wt%; 0.25 wt%) on the spinning process at electrical voltages of 25 kV and 50 kV was studied. The theoretical part describes the properties and the division of polymers and looks at polyvinylidene fluoride (PVDF) as a source material in more detail. Furthermore, the electrospinning method is described, including process conditions and external parameters influencing the process of obtaining fibers. The experimental part describes the preparation of samples by electrospinning and their characterization. Fiber thickness, its appearance, arrangement, and the occurrence of defects when using individual surfactants were evaluated. It was found that the used ionic surfactants affect the thickness of the fibers and their morphology. Homogeneous fibers with a predominant arrangement in one direction, without defects, were obtained.
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Preparation of nanocrystalline ceramic materials made from zirconia oxide
Vlček, Ondřej ; Prajzler, Vladimír (referee) ; Šťastný, Přemysl (advisor)
Bachelor thesis is focused on preparation of nanocrystalline stabilized zirconia ceramics. The theoretical part is dedicated to zirconia ceramics. Theoretical part describes and unveil the transformation-induced toughening mechanism in partially stabilized zirconia ceramics, the processing routes of these ceramic materials and their utilization. The research part describes preparation of yttria partially stabilized nanocrystalline zirconia ceramics by slip casting method.
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Doped ceramic substrates for plasma aplications
Hliničan, Jan ; Šťastná, Eva (referee) ; Šťastný, Přemysl (advisor)
This bachelor thesis summarizes findings on subject: Doped ceramic substrates for plasma aplications. The thesis is divided into two parts. The first part is a literary research focused on topic: production of thin ceramic tapes by tape casting and their use. The second part is experimental. It deals with the preparation of alumina tapes doped with magnesium spinel (MgAl2O4) in different amounts. Phase composition and microstructure will be evaluated on prepared structures. The prepared samples will be used for the production of electrodes for atmospheric plasma discharge.
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Flexible ceramic sheets based on ziconium dioxide
Hliničan, Jan ; Částková, Klára (referee) ; Šťastný, Přemysl (advisor)
The diploma thesis is focused on preparation of thin and highly flexible ceramic tapes from zirconia with a thickness from 70 to 200 m. The thesis is divided into two parts. The first part presents a literary research that focuses on the properties of zirconium dioxide, the preparation of thin ceramic foils and the evaluation of the mechanical properties of ceramic materials. The second part is experimental. It deals with the preparation of thin ceramic foils from colloidal ceramic suspensions produced by epoxy gel-tape casting method. The suspensions were prepared from zirconium dioxide stabilized by 2 and 3 mol.% of yttrium oxide. The maximum deflection and strength was determined on sintered foils. The maximum biaxial strength of 1806 MPa was achieved for 3Y-PC 75 foils with a thickness of 190 m. The maximum deflection of 10.5 mm at a ceramic foil thickness of 75 m was achieved in a 3-point bend with a support span of 30 mm on 3Y-PC 75 samples. At a support distance of 50 mm, the samples were pushed through the gap without damage. These results indicate excellent mechanical properties of the prepared ceramic foils.
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Modern processing methods of porous bioceramics
Šťastný, Přemysl ; Částková, Klára (referee) ; Trunec, Martin (advisor)
Bachelor thesis is written with focusing to bioscaffolds. Thesis is devided into three parts. First part is focused to colloid suspensions, their preparation and consolidation. Second part is focused to preparation methods of porous ceramics. The third part describes scaffolds and their use in medicine. Practical part is focused to gels preparation.
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Multi-phase porous bioceramics bone scaffolds based on calcium phosphates
Smiešková, Jana ; Šťastná, Eva (referee) ; Šťastný, Přemysl (advisor)
This bachelor thesis summarizes findings on subject: Multi-phase porous bioceramics bone scaffolds based on calcium phosphates. The thesis is divided into two parts. The first part is a literary recherche speaking on topic: Tricalcium-phosphate-based bioceramic materials and their interaction with the body of the recipient. The second part is experimental. It describes the preparation of mixed ceramics (mixture of hydroxyapatite (HA) and tricalcium phosphate (TCP)) and evaluation of their microstructure and changes of phase composition.
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Customized hybrid bioscaffolds for bone regeneration
Šťastný, Přemysl ; Šupová,, Monika (referee) ; Pabst, Willi (referee) ; Trunec, Martin (advisor)
Doktorská práce s názvem Individualizované hybridní podpůrné struktury pro regeneraci kostní tkáně je rozdělena do dvou částí. První část si klade za cíl ukázat vzájemný vztah mezi implantovaným materiálem a kostní tkání a současný stav poznání v oblasti vývoje matriálů na bázi fosforečnanů vápenatých a z nich vyráběných implantátů pro regeneraci kostní tkáně. Koncept individualizace a pečlivého výběru fázového složení implantátu představuje stěžejní body druhé části práce. Individualizace v této práci není chápána jako pouhé dosažení tvarové a rozměrové přesnosti implantátu. Velká pozornost byla věnována mikrostrukturním detailům, fázovému složení a distribuci jednotlivých fází, což umožňuje připravit specifický materiál na základě zamýšlené aplikace. Biologická odezva na připravené materiály byla vyhodnocena pomocí in-vitro a in-vivo testů. Doktorská práce ukazuje jak pochopení základních chemických a fyzikálních vlastností materiálu může pomoc při návrhu implantátu s vynikající biologickou odezvou. In-vivo aplikace navrženého materiálu a jeho srovnání s autograftním kostním štěpem, současným zlatým standardem, je jedinečným a cenným výstupem předložené práce.
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Electrospinning of polyvinylidenfluoride based fibers
Hošek, František ; Šťastný, Přemysl (referee) ; Částková, Klára (advisor)
Electrospinning is one of the rapidly developing methods for obtaining fibers of very small thickness. There is a wide-scale use of nanofibers, and it has a great potential in many fields, such as in medicine, biology, chemistry, electronics, environmental protection, energy-harvesting, and other. Polyvinylidene fluoride (PVDF) appears to be a promising material for fiber production for its excellent mechanical and chemical properties. It is a chemically inert substance, very resistant to thermal stress. The aim of this bachelor thesis is the preparation of PVDF fibers by electrospinning and the study of the influence of three different surfactants on the spinnability of PVDF, on the arrangement and the shape of fibers which are formed during electrospinning. The effect of surfactant concentration (1 wt%; 0.5 wt%; 0.25 wt%) on the spinning process at electrical voltages of 25 kV and 50 kV was studied. The theoretical part describes the properties and the division of polymers and looks at polyvinylidene fluoride (PVDF) as a source material in more detail. Furthermore, the electrospinning method is described, including process conditions and external parameters influencing the process of obtaining fibers. The experimental part describes the preparation of samples by electrospinning and their characterization. Fiber thickness, its appearance, arrangement, and the occurrence of defects when using individual surfactants were evaluated. It was found that the used ionic surfactants affect the thickness of the fibers and their morphology. Homogeneous fibers with a predominant arrangement in one direction, without defects, were obtained.
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Flexible ceramic sheets based on ziconium dioxide
Hliničan, Jan ; Částková, Klára (referee) ; Šťastný, Přemysl (advisor)
The diploma thesis is focused on preparation of thin and highly flexible ceramic tapes from zirconia with a thickness from 70 to 200 m. The thesis is divided into two parts. The first part presents a literary research that focuses on the properties of zirconium dioxide, the preparation of thin ceramic foils and the evaluation of the mechanical properties of ceramic materials. The second part is experimental. It deals with the preparation of thin ceramic foils from colloidal ceramic suspensions produced by epoxy gel-tape casting method. The suspensions were prepared from zirconium dioxide stabilized by 2 and 3 mol.% of yttrium oxide. The maximum deflection and strength was determined on sintered foils. The maximum biaxial strength of 1806 MPa was achieved for 3Y-PC 75 foils with a thickness of 190 m. The maximum deflection of 10.5 mm at a ceramic foil thickness of 75 m was achieved in a 3-point bend with a support span of 30 mm on 3Y-PC 75 samples. At a support distance of 50 mm, the samples were pushed through the gap without damage. These results indicate excellent mechanical properties of the prepared ceramic foils.
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