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Changes in structure and phase composition in the surface of tram rail
Švábenská, Eva ; Roupcová, Pavla ; Schneeweiss, Oldřich
We have investigated structure and phase composition of surface layer of tram rails after long time running and the results were compared with those obtained on the original part of material. Changes due to effects of severe plastic deformation together with thermal shocks by friction process were expected. The information about structure and phase composition was obtained by optical and scanning electron microscopy, X-Ray Powder Diffraction, Mössbauer Spectroscopy and Glow Discharge Emission Spectroscopy (GDOES) and this was completed by microhardness measurements. The results show that the surface layer in comparison with the original material exhibits important changes in grain structure, an increase in microhardness and high content of iron oxide and hydrooxides. According to the depth profile of the chemical composition measured by GDOES there is an increase in carbon content in the surface layer which can be effect of up-hill diffusion.
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Two phase flow of water and air, flat jet above the plate, jet sloping 75° and 90°
Říha, Zdeněk
The report contains CFD results and description of the two phase flow water and air. Water comes into the computational domain through\nsimplified nozzle which creates water flat jet with spraying angle c. 40o. The flat jet falls on the wall surface where flows along the surface plate in all directions (x,y mainly). The aim of the work is to show how the falling water flows on the wall surface with help of advanced CFD model. Two cases had been solved there with various jets sloping to the surface plate. The first case contains results with configuration of the geometry for the jet sloping 75o and second case contains results with configuration of the geometry for the jet sloping 90o, see enclosures 1 and 2. Given calculation had been done as steady state calculations.
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Methodology of the Cooperation between the Director and Actor and Contermporary Theater Practice
Glogrová, Kateřina ; BURIAN, Jan (advisor) ; HRBEK, Daniel (referee)
The thesis deals with the cooperation between the director and actor during individual phases of the staging process as they appear in everyday theatre life. The indiviual phases of the staging process are supplemented by the author's own experience with managing the actors, which she gained especially in the course of her studies at the Drama Faculty of AMU. The second part of the thesis investigates the issues of inner truthfulness and the possibilities of its achievement within the production of a play. As a part of collecting the material for the thesis, the author conducted a research, which included interviews with three professional directors - Hana Burešová, Ladislav Smoček and Štěpán Pácl, whose methods of work are described. In the final part of the thesis the author states that it is difficult to draw general conclusions about the cooperation between the director and actor because it is always of subjective nature. The issue of inner truthfulness is similarly difficult to generalise. Due to the multiplicity of options, however, neither of them loses attractiveness for further research.
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Mechanochemical Preparation of Alumina-Ceria
Jirátová, Květa ; Spojakina, A. ; Tyuliev, G. ; Balabánová, Jana ; Kaluža, Luděk ; Palcheva, R.
Ceria containing catalysts play an essential role in heterogeneous catalytic processes. However, ceria shows poor thermal stability and low specific surface area and therefore, many studies have been done to improve its properties by combination with other oxides. Alumina-ceria is substantial component of the three ways catalysts, due to the ceria ability to function as the buffer of oxygen and to enhance the oxygen storage capacity of the catalysts. Ceria in these catalysts also functions as structural promoting component, increasing alumina stability towards thermal sintering. Promising method of oxides preparation, very interesting and simple but not sufficiently studied yet is a mechanochemical synthesis. Here we report on the synthesis of nano-sized alumina, ceria and ceria-alumina of various compositions by a wet solid phase mechanochemical reaction of hydrous aluminum, and/or cerium nitrate with ammonium bicarbonate after addition of a small amount of water. The aim of this contribution is to study processes being in progress during synthesis of the mixed oxides, interaction between components and their mutual effect on the properties of resulting products. The phase evolution during mechanical milling and the subsequent heat treatment of precursors were studied by X-ray diffraction, DTA/TG, H2-TPR, NH3-TPD, CO2-TPD, N2 adsorption at -195°C, IR, and XPS spectroscopy. Alumina and mixtures of alumina with different quantities of CeO2 (1- 18 wt. %) were synthesized by mechanochemical method from aluminum nitrate, cerium nitrate and ammonia bicarbonate.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22015083108560 - PDF
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Analysis of Financial Time Series in Crisis
LOPATÁŘ, Antonín
This bachelor thesis is focused on the methods of analysing an additive model of time series. The theoretical part is aimed on history of business cycle, structural and cyclic deflection and individual phases of business cycle. There are described individual theories of business cycle. Crisis as one of the phases is described closer. Further it introduces the methods used in practical part. The practical part contains analysis of individual time series. For example price of gold, LIBOR, PRIBOR, Gross domestic product and other. This time series are analysed by exponential smoothing, moving averages and other methods.
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Nursing procedures in taking blood pressure
SEDLÁKOVÁ, Tereza
By blood pressure is meant lateral pressure or the side pressure of a blood column on the side of a vessel. The pressure is created thanks to the action of heart as a blood pump. This pressure is not the same in different parts of the bloodstream. By the blood pressure is meant the arterial pressure or pressure in the artery, so the pressure in big blood vessels. The highest values are reached in the expulsion phase of the heart action, which is called systole. The lowest values are reached in the phase of filling heart chambers, which is called diastole. The sole nursing procedures required in the process of taking a blood pressure reading are many and all must be followed. This thesis is composed of a theoretical part and practical part. Introduction to the theoretical part is composed of the main terminology from the physiology of blood pressure. In the theoretical part we follow with division on hypotension and hypertension, which are the most common diseases related to blood pressure, with diagnosis and recommendation for treatment. This thesis also offers information about measuring blood pressure by the invasive and the non-invasive method. The theoretical part is focused on the importance of the nurse in the process of measuring blood pressure with emphasis on her knowledge and practical skills.
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Ability of dogs to discriminate human odor exposed to chemical detergent
Čajágiová, Martina ; Vyplelová, Petra (advisor) ; Jaroslav, Jaroslav (referee)
In the recherche part of our thesis we familiarize ourselves with the human odor, theories of its origin, definition, anatomy of human skin and odors, composition of individual human odors and with odor secretion. We also look closer on the topics of odor absorbent and its use in the world, the transmission of odors to odor sensors and securing of scents. This section of our thesis discusses the resistance and survival abilities of odor, scent identification method and its history, organic acids, and defines the application of laundry detergents and ultrasonic washers. Aim of our thesis was to verify the relevance of the use of chemical detergents in the purification process when working with scents. We tried to verify the ability of detergents to degrade the human scent on odor absorbents to such an extent, that specially trained dogs would not be able to identify it. Our experiment was following a precise determination methodology. In the first phase samples were collected from the hands of targeted persons to a scent carrier - a metal cylinder (extirpate odour), by one researcher. In the second phase samples were collected from the body to a textile carrier, by another researcher. The metal scent carriers were processed. Some of them were left as they were (control sample) and some were exposed to chemical detergents with and without usage of an ultrasonic washer.
In the experiment where we tried to identify the odour samples, six bitches of German shepherd were used. They were specially trained for odour identification. Each dog was let three times to identify the target scent exposed to a detergent and three times to identify the target scent not exposed to a detergent. Target smell was randomly deposited between other samples and its position was changed, so that the handler did not know its position and thus was unable to affect the work of his dog. The indicator of positive identification was a sign the dogs were taught - to sit or lay in front of a sample.
Any dog was unable to identify the scent which was exposed to chemical detergent and all dogs identify the scent unexposed to a chemical detergent. Our experiment has shown that the use of chemical detergents in the purification process when working with scents is relevant to the degradation of individual human scent.
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The use of (nano)oxides for metal and metalloid stabilization in contaminated soils
Michálková, Zuzana ; Komárek, Michael (advisor) ; Luke, Luke (referee)
The main objective of the thesis was to evaluate the potential of selected Mn and Fe (nano)oxides for the stabilization of metals and metalloids in contaminated soils. The research was focused basically on three materials - commercial nanomaghemite (Fe III), nanomagnetite (Fe II,III) and a synthetic amorphous Mn oxide (AMO). The main aim of the work was to provide a complex view on the chosen stabilizing amendments regarding not just their direct influence on contaminants mobility and stabilization mechanisms, but also their stability and alterations in soil conditions together with influence on soil microorganisms and higher plants. Firstly, adsorption properties of the tested materials towards Cd, Cu, Pb and As were investigated. In this context, the most effective material showed to be the AMO reaching one to two orders of magnitude higher adsorption capacities than Fe III and Fe II,III under given experimental conditions. Interestingly, the rate of As(V) adsorption onto AMO was increasing with increasing pH as a result of high pHzpc of the AMO (8.1) and significant dissolution of this phase at lower pH values. As a next step, the influence of (nano)oxides on metal(loid)s mobility and other physico-chemical soil characteristics after application to contaminated soil was examined. Again, the AMO proved to be the most efficient in reducing mobile pools of Cd, Cu, Pb, Zn and As. On the other hand, Fe III and Fe II,III addition had generally less significant effects on contaminants mobility. AMO application further resulted in an increase of soil pH connected with AMO dissolution and unwanted decomposition of soil organic matter. When (nano)oxides alterations in soil conditions were observed, MnCO3 coatings were identified on AMO surface while no significant changes were recorded for Fe III and Fe II,III. As the MnCO3 formation was connected with increased AMO stability, AMO particles synthetically covered with MnCO3 coating (denoted as SM AMO) were prepared. Although the SM-AMO had a lower mass loss in soil than pure AMO, the stabilizing efficiency was almost the same for both materials. The differences in surface composition of both materials were decreasing with time as MnCO3 naturally precipitated on the AMO surface in soils while the SM AMO coating was gradually dissolving. When investigating the effect on soil microbiota, AMO efficiently promoted soil microbial activity while no significant changes were observed in the case of Fe III and Fe II,III. The AMO was also able to reduce the uptake of Cd, Pb and Zn by sunflower (Helianthus annuus L.), eliminate Zn phytotoxicity symptoms and increase biomass yield. On the other hand, toxic levels of Mn released from the AMO in an acidic soil were found in sunflower tissues. AMO application is thus recommended for contaminated neutral or slightly alkaline pH with a higher cation exchange capacity in order to avoid unwanted release of Mn. Finally, various types of AMO-biochar composite sorbents were recently prepared and field experiment focused on stabilization of Cd, Pb, Zn and As using studied materials is currently under preparation. The combined results from the thesis highlight the importance of a complex experimental approach dealing with all parts of the contaminated soil environment in order to obtain complete information about the efficiency and usefulness of any newly developed stabilizing amendment.
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