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Hydrophobization of sandstone and limestone materials with a thin hydrophilic coating
Rathouský, Jiří
Hydrophobization of the surface of sandstone and limestone materials is an effective method of their protection against the effects of weathering. Effective hydrophobizing agents are solutions of alkyltrialkoxysilanes, especially methyl- or octyltriethoxysilane in a suitable organic solvent (in particular white spirit), and solutions containing polymeric organosilicon compounds also in mineral spirits. It is a major disadvantage of hydrophobization that there is a change in the original appearance of the material due to the increased deposition of dirt on the hydrophobic surface, which is unevenly washed away by rain water, which results in unsightly stains on the surface. Another general disadvantage of hydrophobization is that it renders it very difficult to impossible to carry out another treatment particularly with hydrophilic agents. With the proposed method it is possible to create a thin hydrophilic layer on a hydrophobized surface to ensure the uniform washing away of dirt and to enable the mentioned additional surface treatment. Given that the depth of its removal may be precisely controlled in this process, the hydrophobization will be removed only to the desired depth and will not therefore undermine the effectiveness of the hydrophobization. The new method of hydrophobization of sandstone and limestone materials with a thin hydrophilic coating is based on a two-step process comprising the surface hydrophobization using an agent comprising alkyltrialkoxysilanes or polydimethylsiloxane polymers in an organic solvent to a sufficient depth, and the removal of a thin surface layer of the hydrophobization, bound to the surface of the material, with a thickness of approximately 1 mm.
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Messenger RNA stability and microRNA activity in mouse oocytes
Flemr, Matyáš ; Svoboda, Petr (advisor) ; Motlík, Jan (referee) ; Hampl, Aleš (referee)
The oocyte-to-zygote transition represents the only physiological event in mammalian life cycle, during which a differentiated cell is reprogrammed to become pluripotent. For its most part, the reprogramming relies on the accurate post-transcriptional control of maternally deposited mRNAs. Therefore, understanding the mechanisms of post-transcriptional regulation in the oocyte will help improve our knowledge of cell reprogramming. Short non- coding microRNAs have recently emerged as an important class of post-transcriptional regulators in a wide range of cellular and developmental processes. MicroRNAs repress their mRNA targets via recruitment of deadenylation and decapping complexes, which typically accumulate in cytoplasmic Processing bodies (P-bodies). The presented work uncovers an unexpected feature of the microRNA pathway which is found to be suppressed in fully-grown mouse oocytes and through the entire process of oocyte-to-zygote transition. This finding is consistent with the observation that microRNA-related P-bodies disassemble early during oocyte growth and are absent in fully-grown oocytes. Some of the proteins normally associated with P-bodies localize to the oocyte cortex. At the final stage of oocyte growth, these proteins, together with other RNA-binding factors, form subcortical...
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The content and binding of silver in galena
Němec, Matěj ; Goliáš, Viktor (advisor) ; Zachariáš, Jiří (referee)
Galena as the most important silverbearing ore is found in almost every Ag deposit. If the content of Ag is higher than 0,5 wt. % then is called galena solid solution - PbSss. The galena Ag has two forms of occurrence - inclusions and isomorphic silver. Aboat ninety percent of galena Ag is product of retrograde proces of PbSss cooling. These are matildite (AgBiS2), miargyrite (AgSbS2), diaforite (PbAg3Sb3S8), freislebenite (AgPbSbS3), pyrargyrite (Ag3SbS3) aramayoite (Ag(Sb,Bi)S2), freibergite (Ag12Sb4S13), gustavite (AgPbBi3S6) etc. The smaller amounth of isomorphic Ag is substituted as 2Ag+ = PbII+ . Under the usual conditions of deposition (200 - 300řC) , the solubility of Ag2S is to low. The content of Ag in galena under these conditions is not higher then 0,4 mol. % at 615řC. Most of the isomorphic Ag is bound in coupled substitution Ag+ + Bi III+ /Sb III+ = 2 PbII+ . In this case the content of Ag in PbS can be as high as 9 wt. % at 350 - 400řC. At the deposites where wasn't activated this Bi/Sb - Pb coupled substitution the content of Ag in galena is very low. The content of trace elements of Ag, Bi and Sb can also influence the galena crystal habit. Galena rich on Bi ususaly creates octahedral crystals. Galena with a higher content of Ag and Sb usualy creates cubic crystals.
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Fracture behaviour of ceramic laminates with strong linked layers
Chlup, Zdeněk ; Slabáková, Lenka ; Drdlík, D. ; Hadraba, Hynek ; Dlouhý, Ivo
Multi-component ceramics materials having layered structure possess potential to be more convenient than monolithic ones. Depending on design a number of laminated structures can be distinguished. The most common division is by behaviour of layer interface i.e. with strong or weak interfaces. In this contribution the fracture behaviour of the laminates with strong interface allowing creation of residual stresses within layers will be described. Presence of residual stresses can enhance fracture properties. The alumina and zirconia were the components and electrophoretic deposition was used to prepare the laminate. Fracture behaviour was investigated using three point bending test of SEVNB specimens. Fracture surfaces were reconstructed and crack propagation changes were determined. Influence of residual stresses on fracture behaviour was found and described.
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Almost optimal trading strategies for small transaction costs
Jusko, Martin ; Dostál, Petr (advisor) ; Štěpán, Josef (referee)
We consider agent trading futures on a market with small transaction costs. Her capital is deposited on a money market account, where compounding is possible. Arithmetic Brownian motion with random coefficients is considered as a model for futures strike price. The coefficients are assumed to be bounded Itô processes with bounded coefficients. Under these assumptions, an almost optimal interval strategy is derived, which almost maximizes expected utility in certain stopping times under hyperbolic absolute risk aversion utility function. Furthermore, under logarithmic utility function the derived strategy almost maximizes expected utility in wide class of (integrable) stopping times.
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The process of compensation for the victims of the romany holocaust in the Czech Republic
Zdařilová, Eva ; Červenka, Jan (referee) ; Závodská, Milada (advisor)
The Roma living in the Czech Republic spent WWII. in the Protectorate Bohemia and Moravia, in "Sudety", occupied by the Germany, in south Slovakia, occupied by the Hungary and in the Slovak Republic. From the first three regions the Roma were gradually deported to internment and concentration camps, in the Slovakia they had to face various suppressions like mass displacement from the villages, forced labour and finally they had to hide in the forests to protect themselves from Gestapo and Hlinka's guard. In the year 1998 the Czech Roma had the first opportunity to ask for the financial allowance for the suffered distress and torture. Swiss banks deposited 273 million CHF into a special fund, 88% out of this sum should have been divided to Jews and 12% to victims without Jewish origin. The fund did not accept any individual requests but cooperated with local organizations. In the Czech Republic it was first and foremost the League for the assistance to Roma war victims, which was founded by the Roma civic initiative in this purpose. The League set a list of about 3000 applicants, who met the requirement of the date of birth before 31st December 1944, who spent the war-time in the Czechoslovakia and who were able to prove they are socially needy. However, the Swiss fund did not presume so high number of Czech...
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Isotope composition of fluids extracted from fluid inclusions
Drahota, Jakub ; Žák, Karel (referee) ; Zachariáš, Jiří (advisor)
Gold-bearing mineralizations and gold deposits in the Bohemian Massif are restricted mainly to Central Bohemian metallogenic zone. In this thesis, the quartz gangue from Mokrsko, Kašperské hory, Jílové u Prahy and Kasejovice deposits was studied, which originated from H2O-CO2±CH4±N2 fluids at temperatures from about 500 to about 300 řC. Quartz was mechanically and chemically purified and CO2 for subsequent isotopic analysis of carbon, was cryogenic separated in a vacuum line for thermal decrepitation of fluid inclusions. Measured value of δ13 C-CO2 varies from -15,7 to -6,5 ‰ PDB. The spread of δ13 C-CO2 data excludes single source of carbon. Up to two different carbon sources can be demonstrated for most of the studied localities. The most likely source appears to be carbon of homogenized upper crust, and organic carbon mobilized during metamorphic processes.
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Regulation of commercial banking by the central bak
Mach, Petr ; Kotáb, Petr (advisor) ; Boháč, Radim (referee)
- 70 - 10 Resumé Regulation of commercial banking by the central bank This diploma thesis deals with regulation and supervision of a commercial banking. It is focused on changes which were made in this area during the last several years. The next purpose of the thesis is evaluation of reforms which are proposed as an answer to the present financial crisis. In an introductory passage I generally define regulation and supervision of the commercial banking, refer to organizations which have key importance in the banking regulation, enlarge upon risks to financial stability of commercial banks (credit, operational, likvidity, interest rate, capital and market risk), introduce causes for existence of the banking regulation and mention its objectives. Next I deal with particular methods of the regulation, for example a minimum capital requirements, a financial reporting and desclosure requirements, large exposures restrictions, a deposit guarantee or position of the central bank as a lender of last resort. The main part of the thesis is focused on descriptions of changes which were made during the past few years and after that I evaluate drafts that are proposed as a answer to financial crisis which has last from 2007. Main changes are connected with an approval and an implementation of a new capital adequacy...
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Foundation and Origin of a Limited Partnership
Novotná, Eliška ; Kalinová, Miluše (advisor) ; Žák, Květoslav (referee)
It is very popular to enter a market as an entrepreneur in the Czech Republic today. A person should be knowledgeable about the Czech law and decide whether s/he intends to carry business either as a sole proprietor or as a corporation. This bachelor's work provides the information and advice how to start, when a business organization, concretely a limited partnership/Ltd., is going to be founded. There are going to be explained concrete steps that lead to a foundation and origin of a limited partnership in this work. Founders of a business organization need to form the Articles of Partnership at the beginning. They should also find suitable premises for their future corporation. The next step that is important to do is to get an entrepreneurial licence for that activity that the corporation will carry on. One of the most important steps to establish a company is to file a proposal for the incorporation of the business into the Register of Companies. When the business is registered in the Register of Companies, then it can perform its entrepreneurial activity according to the incorporation act. In case of a limited partnership/Ltd. the co-partner who is bound to a deposit duty should pay up his deposit as soon as possible after the business is incorporated. After reading the above instructions the reader may think that the establishment and origin of a company is quite easy. I hope s/he will recognize that it is necessary to be well informed about legal procedures for establishment of a business at the end of this bachelor's work. The mere existence of a company itself is not sufficient. The business must find its customers and reach its target. For that reason it is essential to create an entrepreneurial plan and a marketing strategy for a concrete company. Thus, an entrepreneur should combine the knowledge of law and economics if s/he wants to be successful in the market.
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Resolving banking crises
Juhász, Michal ; Seknička, Pavel (advisor) ; Bažantová, Ilona (referee)
The Diploma Thesis deals with the banking crisis and aims to account for different approaches to the understanding of the nature of banking crisis. The Thesis further aims to provide answers why the banking crisis are caused and why so far there are no measures that would effectivelly prevent such crisis. At first, the Thesis states the definition of banking with the emphasis on banks as the institutional backbone of the current functioning of the financial system. The Thesis pays specific attention to the characteristics of two basic legal banking instruments, particulary loans and deposits. While acknowledging the loan expansion, the thesis argues the role of regulatory authorities and the limits of their competences in regards to the prevention of crisis. Followingly, the Thesis offers a view on a banking crisis phenomenon with appropriate historical overview outlining the banking crisis in Czechoslovakia in years 1918 to 1939 and after 1989, the loan expension influence on the business cycles and approaches to banking crisis solving in respect to stabilization of the banking system and restructuring of banks. At last but not least, the Thesis sums up the global financial crisis that started as a banking crisis, respectively as a crisis of one segment of the banking market in the United States...
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