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Synthesis of core/shell quantum dots for diagnostics
Mihajlović, Ana ; Vaculovičová, Markéta (referee) ; Pekárková, Jana (advisor)
This thesis deals with biosensors based on modified semiconductor core/shell quantum dots (QDs) for diagnosis. The work is divided into four main parts. The first one discusses the theory required for the use of QDs in bioaplications, there are described methods of synthesis, modification, application and bioconjugation of QDs. In the experimental part, CdTe/ZnS QDs with core/shell structure were prepared, in which the core was modified by MPA, GSH and TGA. In the next step, these QDs were further modified using CDI, EDC and NHS as mediators in order to increase affinity to BSA (bovine serum albumine) and IgG (imunoglobuline G). Prepared conjugates were characterized by fluorescence spectroscopy (Infinite M200Pro, Tecan) and capillary electrophoresis (Agilent 7100).
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Chemical modifications of hydrogels from natural polysaccharide
Poštulková, Hana ; Žídek, Jan (referee) ; Vojtová, Lucy (advisor)
V teoretické části práce by shrnuty chemické a fyzikální vlastnosti, chemická struktura a využití přírodního polysacharidu gum karaya. Hlavním cíle diplomové práce byla alkalická modifikace původní nerozpustné gum karayi na rozpustný produkt, který může být v budoucnu využit pro další aplikace například v medicíně. Nerozpustnost gum karayi je způsobena přítomností acetylových skupin a vícemocných iontů ve struktuře polysacharidu. Byly zkoumány optimální podmínky pro modifikační proces. Pro modifikaci byl použit hydroxid sodný, draselný nebo amonný a čas modifikace od 1 minuty po 24 hodin pro roztok originální gum karayi s koncentrací od 0,1 do 3 %. Pro určení chemického složení originálního a modifikovaných vzorků byla využita FTIR. Bylo prokázáno, že vzorky A2, B1 - 7, C1 - 8 a E1 - 2 byly zcela deacetylovány, protože pás pro acetylovou skupinu nebyl v FTIR spektrech pozorován. Odstranění acetylových skupin alkalickou modifikací bylo taktéž potvrzeno 13C CP MAS NMR. Pomocí XRD byl prokázán amorfní charakter originálního vzorku. Množství vlhkosti a teplotní stabilita vzorků byly zkoumána pomocí TGA. Bylo zjištěno, že termální stability originální gum karayi je vyšší než u modifikovaných vzorků. Termální stabilita modifikovaných vzorků byla ovlivněna reakčními parametry. Entalpické změny vzorků byly studovány pomocí DSC, nicméně nebyly pozorovány žádné významné rozdíly mezi modifikovanými vzorky a originální gum karayou. Prvkové složení bylo určeno pomocí ICP-OES a byla potvrzena přítomnost vápníku, draslíku a hořčíku ve struktuře polysacharidu. Molekulová hmotnost modifikovaných vzorků byla měřena pomocí GPC a byla stanovena na 8 milionů g·mol-1. Reologické měření roztoků gum karayi bylo provedeno pro určení lineární viskoelastické oblasti. Dále byl sledován efekt NaCl na viskozitu originálního vzorku. Viskozita klesala s vyšším množstvím NaCl. Pokles viskozity originálního vzorku je způsoben výměnou vápenatých iontů za sodné, což vede k uvolnění fyzikálně vázané struktury a tím k vyšší rozpustnosti vzorku ve vodě.
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Chemical modifications of polypropylene surfaces
Pospíšek, Marek ; Petrůj, Jaroslav (referee) ; Kučera, František (advisor)
Diploma thesis is focused on modification and characterization of polypropylene (PP) products surfaces by the chemical way. In theoretical part of thesis are summarized the current knowledge of this topic including characterization methods. Polypropylene surfaces were modified by acrylic monomers (acrylic acid, acrylic acid with 20 mol% content of sodium acrylate and acryl amide). Modified surfaces were characterized by infrared spectroscopy with ATR technique. The comparative parameter was carbonyl index determined from absorption peaks of functional methyl groups (2950 cm-1 ) and functional carbonyl groups (1700-1750 cm-1) of FTIR-ATR spectra. Determination of effect of initiator concentration on the modification process was done for acetophenone and benzophenone. There were determined the time dependence of carbonyl index for time from 0 to 600 s of mentioned monomers. In the same condition were modified test specimens designed for preparation of adhesive joints. Joints were bonded by cyanoacrylate adhesive that provide reaction with surface of polyacrylic acid. There were founded conditions of modification that provided strength of adhesive joints higher than strength of original PP. There were identified changes of surface roughness by using of confocal microscopy.
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Modification of polyvinylalcohol of lower saponification degree for preparation of MDF composites
Kotrla, Jan ; Švec, Jiří (referee) ; Šoukal, František (advisor)
The subject of the bachelor thesis is modification of polyvinylalcohol of lower saponification degree for preparation of MDF composites. MDF composites are characterized by their extreme mechanical properties. However, their low resistance to moisture is a significant disadvantage. Increased moisture resistance could be achieved by grafting suitable functional groups on the polymeric chain and the subsequent cross-linking. The study is focused on optimization of the number of functional groups and the cross-linking conditions. The number of grafted functional groups was determined by UV – VIS, XPS analysis and IR spectrophotometry. The solubility of the crosslinked samples was measured by rheological measurements.
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Formula Student Clutch
Drbal, Milan ; Zubík, Martin (referee) ; Janoušek, Michal (advisor)
This thesis deals with clutches used in Formula Student competition, calculation of the clutch used in Husqvarna FE 501and Husaberg FE 570 motor and modification of FE 570 clutch for usage in turbocharged version of the Husqvarna FE 501 with Garret turbocharger. The clutch is multi-plate wet clutch with pressure plate spring. Modification is done by installing bigger clutch set from Husaberg FE 570 engine, which is more suitable for usage in a racing car thanks to bigger torque transferred by the clutch. In the first part a research of multi-plate clutches, which can be found in most of the modern motorcycle engines was done. In the second part the calculations were made in order to set an approximated torque possible to transfer with stock Husaberg FE 570 clutch and a modification design for improvement with realisation.
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Production of Ductile Iron with Feritic Matrix
Blaha, Marek ; Šupálek, Milan (referee) ; Molliková, Eva (advisor)
This bachelor thesis deals with the properties and production of ductile cast iron with ferritic matrix. Theoretical part is focused on basic information about ductile iron, its chemistry, structure and mechanical properties. The production of ductile iron with ferritic matrix in JMA Hodonín Ltd is described in the next chapter of this thesis. In the experimental part the real cast is described together with its production technology and material. The practical part is concentrated on comparison of chemical composition, structure and mechanical properties of material of cast and keel blocks made of the same melt. Finally the results of experiments are summarized and the arrangements for improving conformity between material of cast and of keel block are suggested.
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Manufacture of compacted graphite cast iron
Jankes, Erik ; Bouška, Ondřej (referee) ; Záděra, Antonín (advisor)
Compacted graphite cast iron is new kind of cast iron that is applied especially in car industry. It is necessary to optimize metallurgical process of melting and verify technological behaviour of cast iron at loading production. This bachelor thesis describes the properties and known production possibilities of the material.
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Computational model of heat cycle of Stirling engine
Horák, Jiří ; Hejčík, Jiří (referee) ; Jedelský, Jan (advisor)
This Bachelor´s Thesis deals with heat circulation of a Stirling engine according to the Schmidt theory. In the first part of the thesis there is a short view and characteristic of computational methods for Stirling engine and there are also a few computational models illustrations. The second part describes the Schmidt idealization and its process within the program environment. The final part of the thesis is focused on the realization of the optimal parameters design using a computational model as well as on the comparison of theoretical results with real measured value.
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Compacted graphite cast iron
Švábenský, Petr ; Kaňa, Václav (referee) ; Laštovica, Jaroslav (advisor)
This labor search to summarize the known properties and methods of production of compacted graphite iron. The first part describes the structure, chemical composition, properties and uses. The second part focuses on the possibility of production of vermicular cast iron. Inoculation options and treatment and various manufacturing processes.
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