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Two-step sintering of advanced ceramic materials with various crystal structures
Žalud, Pavel ; Trunec, Martin (referee) ; Maca, Karel (advisor)
The influence of Two-Step Sintering (TSS) process on the final microstructure of oxide ceramics materials with two different crystal structures was studied. Tetragonal zirconia (stabilized with 3mol%Y2O3, particle size 90nm and 140nm ) and cubic zirconia (8mol%Y2O3, 70nm) powders were cold isostatically pressed and pressure less sintered with different heating schedules. The microstructures achieved with TSS method were compared with microstructures achieved with conventional Single-Step Sintering schedule (SSS). The results showed that the efficiency of the TSS of these oxide ceramics was more dependent on their crystal structure than on their particle size and green body microstructure. The method of TSS brought only negligible improvement of the microstructure of tetragonal zirconia ceramics. On the other hand, TSS was successful in the sintering of cubic zirconia ceramics; it led to a decrease in grain size by a factor of 2.
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Treatment of flue gas polluted by NOx II
Jedlička, Filip ; Jecha, David (referee) ; Dvořák, Radek (advisor)
My master’s thesis deals with the problems of NOx abatement that are included in flue gases. The accent is put on combined flue gases treatment throug ceramic candles, where the deposited catalyst enables NOx reduction throug the method of selective catalytic reduction. The main aim of my master’s thesis has been the design of experimental equipment for current removal of gas pollutants (dioxins, VOC and NOx) and fly-ash on catalitic ceramic candle. Design of experimental equipment consisted in the calculation of basic characteristics like pipe diameter, filtration chamber diameter, heater performance etc. During the design it was necessary to build pressure drop model that was split into head loss of ceramic candle and piping system. For the evaluation of experimentally measured data and for description of ongoing catalytic reaction in various operating conditions was made prediction model of catalytical filter. The last chapter deals with planned experimental testings.
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Freezing technology of bull sperm in relation to its survivability and fertilization ability
Doležalová, Martina ; Stádník, Luděk (advisor) ; Jiří, Jiří (referee)
The aim of optimalization the insemination doses production is to provide the highest fertilization ability of spermatozoa during the demanding proces of processing fresh semen and its subsequent cryopreservation. Temperature changes causes spermatozoa damage during the cooling and freezing. Spermatozoa is exposed to cold shock and many others limiting factors, which leads to cell death and therefore to decline of fertilization ability of thawed insemination doses. For increasing spermatozoa resistance, exactly the plasma membrane resistance against cold shock was fraction of egg yolk LDL cholesterol (low density lipoprotein) at various concentrations into the comercially produced diluents added. It is believed that LDL acts possitively to plasma membrane and helps to maintain the fertilization ability of spermatozoa after thawing. Following step in the proces of insemination doses production is slow cooling of diluted semen and equilibration, when the straws are store at cooling box for 30 minutes to 240 hours. This period is necessary to penetrate of certain diluent components into the spermatazoa also maintain the balance between their intracellular and extracellular concentration. Also important is subsequent freezing temperature gradient of insemination doses. The most suitable freezing method is based on computer controlled temperature decline in freezing chamber which allows the precise control of ice crystals formation that could tear and kill the cell.
During 2012 to 2016 was repeatedly collected semen from the group of breeding bulls (n = 27, Holstein and Czech Fleckvieh breed) at AI centre. Semen which fulfill the standard entrance conditions in first step was evenly into several parts divided. For dilution the three types of comercially diluents AndroMed, Bioxcell and Triladyl with and without LDL addition were used. Into the diluents AndroMed and Bioxcell the concentration of LDL 4 %, 6 % and 8% into the dilent Triladyl 6 %, 8 % and 10 % was added. Diluted semen was filled into the glass capillares with volume 0,1 ml and temperature +4 °C. Subsequently the sample was placed to cold bath (0°C) for 10 minutes. Then the volume of capillare with physiological solution (37 °C) was mixed and for next 120 minutes was incubate. The effect of cold shock to proportion of live spermatozoa was evaluated by using Eosin and Nigrosine staining technique during heat test of spermatozoa survivability after spermatozoa heating and after 120 minutes of incubation.
The more suitable semen diluents which provide the higher spermatozoa resistance against cold shock were AndroMed and Bioxcell. Together the possitive effect of LDL addition into the diluents to lower decrease of proportion of live spermatozoa during heat test was found (P<0.05). The most suitable LDL concentration which had a favorable influence at spermatozoa resistance against cold shock was 6 % in diluent Bioxcell. Values of the proportion of live sperm were higher at the beginning of the heat test (+1.31% to + 3.2%) and after 120 minute incubation (+5.82% to +8.41%) compared to other diluents with and without addition of LDL.
In the next step the process of equilibration was optimized, is an important part of insemination doses production. The effect of the length of equilibration for subsequent fertilization ability of spermatozoa was evaluated using spermatozoa motility based of CASA and proportion of live spermatozoa after thawing and during heat survival test lasting 120 minutes (37 ° C). Suitable semen was diluted by comercially used diluent AndroMed based on soya lecithin, filled into the straws (0.25 ml), cooled and equilibrated in cooling box for 30, 120 and 240 minutes and freezed in programmable freezing box applying four types of freezing curves differing in temperature rate decline. There was used standard and by producer recommended 3. phase freezing curve, then 2. phase freezing curve, and 3. phase freezing curve with slower as well as rapid decline of temperature rate in freezing chamber, compared with standard freezing curve. The highest spermatozoa motility was found using 240 minutes of equilibration by +2.72% and +4.58% compared to other lengths of equilibration (P <0.05 to 0.01). The highest proportion of live spermatozoa was found using 120 minutes of equilibration (+6.87 % and +8.68 %). The highest average spermatozoa motility during heat test after thawing was achieved by using 2. phase freezing curve (from +2.97% to +10.37%, P <0.05), also in the proportion of live spermatozoa (from + 4.37% to +8.82%, P <0.01). When evaluating interaction between the length of equilibration and freezing curve (standard 3. phase and 2 . phase freezing curve), the highest average spermatozoa motility and proportion of live spermatozoa using 240 minutes of equilibration by both freezing curves was reached, there was no statistically significant differences. As well as, in all evaluated parts of this study the individual differences between ejaculate of bulls and within semen from one bull (P <0.05) as secondary effect were found.
To maintain good fertilization ability of semen during cryopreservation is necessary to increase the spermatozoa resistance against cold shock using addition of correct concentration of LDL into the commercially used diluents AndroMed and Bioxcell. Subsequently the fertilization ability of insemination dose is influenced by cooling, the length of equilibration and freezing. The length of equilibration 120 minutes and more as well as gentle way of freezing according to freezing curve, which ensures a gradual decrease of temperature in freezing chamber provided the higher average spermatozoa motility and proportion of live spermatozoa.
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Cutting ceramics and its effective use
Kavalír, Vít ; Sedlák, Josef (referee) ; Humár, Anton (advisor)
Master’s thesis are concerned with the cutting ceramic materials and its ef-fective usage. The first part of the thesis is focused on the general properties of the cutting ceramics, its history, development, production and description of the various types. This part includes as well a description of the mechanic-physical properties and the potential of the usage for machining. The second part of the work solves the general evaluation of the cutting power. The main issue in the next part is the identification of cutting ceramics range and the selection accor-ding to main world producers. The fourth part deals with the assessments and the comparison of the working conditions for different types of the machined ma-terials. The technical economic assessment shows the potentials in the total pro-duction costs reduction.
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Position of Ireland after financial and debt crisis
Šišková, Dominika ; Hnát, Pavel (advisor) ; Fialová, Barbora (referee)
This bachelor thesis deals with the development of the Irish economy since the end of 1980S until today. The aim is to learn to what extent the financial and debt crisis that hit Ireland in 2008 came to influence foreign direct investment flows. The thesis will focus more specifically on the resulting changes in investment conditions. The first part of the thesis will take up the sharp upswing in the Irish economy in the 1990s and its equally positive aftermath in the years thereafter, as manifested in various macroeconomic indicators. The second part will discuss the beginnings and the evolution of the Irish financial crisis that in due course led to the country's debt crisis, and will raise the various measures taken to save the national economy. The last and third part of the thesis will focus on the present situation in Ireland, including a comparison with the situation before the crisis. A general conclusion of the thesis will be that the Irish economy now seems to have regained a certain stability, with inward direct investment almost back to pre-crisis levels.
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Quantifying aspects of orthosis in relation to ankle sprain
Znášiková, Ivona ; Jelen, Karel (advisor) ; Kubový, Petr (referee)
Title: Quantifying aspects of orthosis in relation to ankle sprain Objectives: To detect whether various types of ankle bracing affect dynamic postural stability. Investigation of attenuation of vertical forces in different conditions. To determine range of motion for each orthosis. Methods: Monitoring of dynamic variables by piezoelectric measuring device - Kistler recording of dynamic changes. Mathematical modeling of damping characteristics and detected variables. Measuring of range of motion by goniometer with and without orthosis. Results: Results suggest, that bracing conditions have an effect on dynamic postural stability and orthosis limit range of motion. Attenuation of vertical forces is affected by using orthosis. Keywords: ankle instability, orthosis, mathematical modeling, stabilization
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Piracy as a threat to the international security: NATO in the Gulf of Aden
Bambušek, Michal ; Rolenc, Jan Martin (advisor) ; Volenec, Otakar (referee)
This bacherol's thesis deals with a modern and specific threat to security relations -- piracy. It characterizes this threat in the case of the Gulf of Aden, where the Somali pirate networks operated, which triggered an international reaction and intervention. In connection with the threat of piracy, the thesis analyzes in the theoretical part the history and evolution of piracy into its current form, where it focuses on the emergence of piracy in the Gulf of Aden and the roots of the problems in this area. The second chapter focuses on the various organizations that operate in the Gulf of Aden. These are divided into military and non-military organizations. The last part is devoted to the North Atlantic Alliance, which operates in the Gulf of Aden since 2008.
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Legal pre-conditions for parenthood
Mrázek, Lukáš ; Radvanová, Senta (advisor) ; Frinta, Ondřej (referee)
The purpose of this thesis is to analyze the legal pre-conditions for parenthood. These are objectively understood as a set of provisions, which give us the answer, who are the legal parents of a child. These provisions are motivated by an effort to harmonize legal parenthood with biological. They are a source of important statutory rights of an individual, which to some extent determine his/her legal status from the very birth. With statutory rights are subsequently firmly bound public legal consequences. These are mainly a relationship between the individual and the state, in particular the obligation to register a child in the state-led civil registration, and also the acquisition of the citizenship. The relationship of parent and child can be considered as basic and most important personal relationship ever. As a result, various rights and duties arise of this relationship, and therefore the need to regulate such relations by the law has appeared with the evolution of human society, so they were build on a solid basis without being disputed. Every state should thus have the obligation to implement such provisions into its legal order. This thesis is drafted in accordance with the division of the legal pre-conditions for parenthood to motherhood and fatherhood. A short introductory part deals...
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Analysis of business and entrepreneurship sector policy in the town Písek
KOSTOHRYZOVÁ, Andrea
The aim of my thesis is to analyse business and entrepreneurship sector of the town Písek and positive attitude of the local municipality towards private business sector operating on the largest industrial zone in South Bohemia. Theoretical part concentrates on description and explanation of the basic terms and relations dealing with the topic of regional development. Afterwards, I focus on description of public and private sectors and possibilities of providing financial subsidies from both national and EU funds. The first section of practical part concentrates on detailed description of the region Písek from various viewpoints social, demographic, economic, industry sectors and competitiveness. Furthermore, I describe and analyse business and entrepreneurship conditions within the industrial zone lying on the edge of the northern part of the town Písek focusing on the past, present and future. I also describe clusters and evaluate success rate and effectiveness of the town Písek in obtaining financial subsidies from both national and EU funds. The last part uses the findings to compare the industrial zone in Písek with a similar industrial zone in Vodňany. Finally, I summarise and evaluate all findings. I outline the possibilities of further development of the industrial zone Písek and ways to obtain financial subsidies for development of business and entrepreneurship sector in the town Písek from accessible European funds.
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Management of an art collection as an investment opportunity
Kálalová, Jana ; Tyslová, Irena (advisor) ; Prokůpek, Marek (referee)
This diploma thesis is dedicated to the phenomenon of art collecting, which under certain circumstances can be considered as an alternative investment. The aim of the thesis is to examine the possibilities of art collecting and investing in the context of both Czech and world art markets, and determine whether art collecting is a form of investment that can generate future profit. Another goal of the thesis is the creation of recommendations that can help collectors create a quality collection while increasing its value over time, no matter if the collection is to be sold afterwards or not. The thesis is divided into several parts. In the first part I describe the collecting itself, various types of collections, significant collectors and also the institutionalized forms of collections in the Czech Republic and abroad. After that I talk about the art market regarding its selling channels together with their advantages and disadvantages for collectors. Subsequently I focus on the price-making process on the art market which creates the base for the next chapter about investing in art where I describe types and rules of investing in art, and afterwards I define the rules regarding the management of an art collection in general with emphasis on its appreciation. In the end I show a practical example of the artworks price development using the artworks of one well-known Czech artist, where some of the formal theoretical statements are applied about investing in art and building an art collection. The whole thesis is assembled together with the opinions of experts from the art field in the form of expert interviews by adding their practical notes continuously to the text.
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