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Evaluation of corrosion on selected aluminium alloys
Skýba, Pavel ; Tulka, Jaromír (referee) ; Pacal, Bohumil (advisor)
The thesis focuses on the corrosion research of AlCu4Mg1 aluminium alloys of square shape and sheet metal coated in 99.5% aluminium. The theoretical part deals with the characteristics of aluminium, the classification and naming of aluminium alloys and the impact of admixtures on aluminium alloys. In the following chapter a general introduction to metal corrosion, its differentiation according to the type of corrosion attack, mechanisms of corrosion, the impact of corrosive environment, according to the choice of anti-corrosion protection, etc. is given. The main part is devoted to the corrosion of aluminium with a special importance of the impact of admixtures on aluminium alloys, the types of corrosion attack, the impact of corrosive environment as well as of the anti-corrosion protection of aluminium alloys. The corrosion tests in controlled atmosphere are considered in the next chapter, while the last one deals with the evaluation methodology of the process of corrosion. At the beginning of the experimental part all the used samples and materials are introduced. The thesis continues then with an overview and a description of the methods used for experiments. The measurement procedure and the results of the experiments are presented in the following chapter that focuses on the metallographic analysis of the aluminium alloy samples before the experiment and after the corrosion attack. The main part of the chapter deals with the dependence of corrosion speed of the individual aluminium alloy samples on time after being exposed in the climate chamber and the salt fog chamber
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Set of residential buildings in SM6, Staré Město - Project planning implementation of construction
Běťák, Rostislav ; Novotný, Michal (referee) ; Šlanhof, Jiří (advisor)
The master thesis with the name Set of residential buildings in SM6, Staré Město - Project planning implementation of construction solves preparation and realization of building. The aim of master thesis is to design of time, financial, material and human resources. The thesis contains calculation, time schedule, building-site, technologicals standards, controls and trials plans, design of mechanism, study of realization of the main stages. The thesis is prepared on the basis of project documents provided by the investor with the approval of the design office.
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Piston for 147kW 4-stroke SI-engine
Hejda, Tomáš ; Svída, David (referee) ; Dundálek, Radim (advisor)
This bachelor’s thesis deals with the design of piston for 147 kW 4-stroke SI-engine, which is used in Octavie 2,0 TFSi RS. The work is focused to main dimensions of the piston, to make it able to work in difficult, temperature and strength conditions as exposed to in its lifetime. One of the most important part of design this piston is strength calculation.
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The design of a quadrocopter for food delivery
Gryc, Matěj ; Čípek, Pavel (referee) ; Skurka, Šimon (advisor)
Online delivery of hot food to the customer's home has become standard. However, as a result of the covid-19 pandemic, methods of safe delivery that do not require interpersonal contact are now being sought. The use of drones, which are already being used in some countries to transport goods and materials, seems promising. This bachelor thesis deals with the design and assembly of a quadcopter designed for food delivery. First, the frame was designed, which was largely fabricated using 3D printing. Based on calculations, the electronics including batteries and motors were selected. Then the mechanism by which the food transport will be mediated was designed. Once constructed, the functionality of the quadcopter and delivery mechanism was tested. Finally, the design was evaluated and possible improvements were mentioned.
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Vasodilatory effects of 3-hydroxy phenylacetic acid: ex vivo mechanism of action
Štefancová, Monika ; Pourová, Jana (advisor) ; Vokřál, Ivan (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Monika Štefancová Supervisor: doc. PharmDr. Jana Pourová, Ph.D. Title of diploma thesis: Vasodilatory effects of 3-hydroxy phenylacetic acid: ex vivo mechanism of action It is known from clinical studies that the intake of polyphenols from food acts as a prevention of cardiovascular diseases. However, the parent compounds themselves often have low bioavailability. The emphasis is therefore on their bioactive metabolites. 3-hydroxy phenylacetic acid (3-HPAA) is among such metabolites. The aim of this study was to verify the mechanism of the vasodilatory effect of 3-HPAA using standardized ex vivo method on an isolated pig coronary artery. The administration of 3-HPAA resulted in relaxation of maximally contracted segments of porcine artery by mechanism partially dependent on the integrity of endothelium. By inhibiting endothelial nitric oxide synthase, the relaxation was significantly impaired. The blockage of SKCa and IKCa channels, muscarinic receptors, cyclooxygenase or L-type calcium channels did not affect relaxation. Thus, 3-HPPA causes dose-dependent vasodilatation of coronary arteries ex vivo at least partially mediated by endothelium with the participation of nitric oxide. Key words:...
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Vasodilatory effects of 4-methyl catechol: ex vivo mechanism of action
Kuzdřalová, Kateřina ; Pourová, Jana (advisor) ; Smutná, Lucie (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Student: Kateřina Kuzdřalová Supervisor: doc. PharmDr. Jana Pourová, Ph.D. Title of diploma thesis: The mechanism of vasodilation effect of 4-methylcatechol ex vivo Keywords: rat, aorta, flavonoids, 4-methylcatechol, vascular smooth muscle, vasodilation Flavonoids belong to the group of polyphenolic bioactive substances found abundantly in plants, fruits and vegetables. Thanks to their pharmacological and biochemical effects, they play a crucial role for human health, especially in the prevention of numerous diseases - metabolic syndrome, osteoporosis, atherosclerosis and also diseases of a cardiovascular system. The aim of the diploma thesis was to determine the mechanism of the vasorelaxant effect of one of the most important metabolites of flavonoids - 4-methylcatechol. For the research we used a standardized ex vivo method on isolated Wistar rat aortic rings. We were able to confirm the vasodilatory effects of 4-methylcatechol. We also confirmed the fact that the flavonoid metabolite directly affects a vascular smooth muscle. Furthermore, we found that the tested compound potentiates the vasodilatory activity of sodium nitroprusside and forskolin, and that vasodilation depends on the activity of...
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Design of a device enabling the reconnection of a glider to a towing aircraft
Ryba, Filip ; Löffelmann, František (referee) ; Sklenář, Filip (advisor)
This bachelor thesis deals with the design of a two-part system for connecting a glider and a towing aircraft in the air. The theoretical part deals with a summary of the principles of glider functions and an analysis of the reconnection attempt. The practical part discusses the proposed parts of the concepts that could fulfil the function and their combination forms into a final design solution. The solution is displayed in the drawing documentation and verified by manual and FEM calculations.
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The role of T regulatory cells in kidney transplantation
Urbanová, Anna ; Stříž, Ilja (advisor) ; Zajícová, Alena (referee)
T regulatory lymphocytes (Treg) belong to the CD4+ cell group. They are an essential part of the immunity system. Treg cells prevent from excessive activation of effector T cells and they keep the tolerance to the tissues of the body. They have high expression of CD25 and the transcription factor Foxp3. We distinguish two basic populations of Treg cells: natural Treg cells (nTreg) created in the thym and representing 5-10 % of all CD4+ cells, and induced Treg cells (iTreg), created from naive CD4+ cells in the periphery.Their regulatory effect is well-known, therefore using of Treg cells could bring about a huge treatment potential for patients with a transplantated kidney. Healthy people and patients tolerant to the transplantated kidney show higher occurance of circulating Treg cells and the Treg cells present in the graft unlike patients with chronical rejection. The tolerance is cancelled with the damage of CD4+ CD25+ cells.For a graft acceptance it is necessary to treat the patient after the transplantation with immunosuppressive medicaments resulting in suppression of immunity reaction against the graft. Their disadvantages are side effects often resulting in the patient's death. Moreover they often have a negative impact on survival and expansion of Treg cells. The analysis of flow cytometry has...
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Cytokines in the effector function of regulatory T cells
Zadražil, Zdeněk ; Holáň, Vladimír (advisor) ; Stříž, Ilja (referee)
Regulatory T cells (Treg) are an important control mechanism within the Immune system (IS). Tregs prevent overactivation of effector T cells or autoreactive cells from invading organism-derived tissues. Treg are characterised by expression of surface molecules, CD4, CD25 and by an intracellular transcription factor forkhead box protein 3 (FoxP3). There are two basic populations of Treg, naturally occuring Treg (nTreg) developing in the thymus and induced Treg (iTreg) rising from CD4+ T cells in periphery, which are also precursors for T helper cells. In spite of an outgoing intensive research, there is still no clear clue which mechanisms are used by Treg to inhibit other effector cells. First in vitro experiments showed, that those mechanisms are of a contact dependent manner and do not use secreted molecules. But in vivo experiments showed the exact opposite. Those studies showed that secretory molecules, such as interleukin (IL)-10, IL-35 or transforming growth factor beta (TGF-β), are important in the effectory phase of Treg. Since the first experiments other distinct mechanisms of supression by Treg cells have been discovered. Those mechanisms seem to be important only in particular situations, particular cell assays or with using of specific experimental models. The reasons for this...
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