National Repository of Grey Literature 287 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
Membrane vesicles in bacteria and their role in antibiotic resistance
Benešová, Anna ; Konopásek, Ivo (advisor) ; Pospíšil, Jiří (referee)
Membrane vesicles are produced by both Gram-positive and Gram-negative bacteria. Mechanism of their formation differs between these two groups of bacteria. It is caused by the different structure of their cell envelope. Gram-negative bacteria contain outer membrane and membrane vesicles can originate from this membrane. Membrane vesicles of Gram-positive bacteria are derived from the cytoplasmic membrane. They have to cross the barrier of the thick layer of peptidoglycan. Membrane vesicles contain cellular components whose properties enable vesicles to fulfil various functions. Antibiotic resistance can be counted as one of these functions. This thesis discusses three ways used by the membrane vesicles to protect the cells from antibiotics: transport of enzymes that degrade antibiotics, removal of antibiotics from cell's surroundings and role of membrane vesicles in horizontal gene transfer.
Calculation program for heat exchanger design
Švec, Dalibor ; Baláš, Marek (referee) ; Pospíšil, Jiří (advisor)
The diploma thesis is focused on creating a calculation software for designing heat exchanger. The software will not calculate one single heat exchanger but will recommend all heat exchangers which meet the requirements. Then, user can decide which heat exchanger is best suited for the specific application and make a comprehensive calculation. Part of the diploma thesis is to verify correctness of the software and make a parametric studies. Parametric studies will be focused on baffle cut, baffle spacing, tube pitch, and tube thickness and its effect on heat transfer and pressure drop.
Design of a pump and pipeline to ensure higher safety of the nuclear power plant
Ošťádal, Michal ; Milčák, Pavel (referee) ; Pospíšil, Jiří (advisor)
The main goal of the diploma thesis is to design the hydraulic part of the new piping system, which is added to the existing project of the Dukovany Nuclear Power Plant. At the beginning of the work is theoretical basis for the design of the hydraulic part. The next part is the selection of piping material for aggressive refrigerant with subsequent verification of the pipe wall thickness. The piping system is designed with specific components from the companies SIGMA GROUP a.s., ARAKO spol. s.r.o. and ARMATURY Group a.s. In the last part, hydraulic solution is developed and commented using the excel program. The piping system is processed into the drawing documentation including bill of materials.
Impactor for laboratory capture of fine particles
Kodad, Daniel ; Poláčik, Ján (referee) ; Pospíšil, Jiří (advisor)
The focus of this master’s thesis is the issue of fine dust particles suspended in the air and their measurement. The thesis explains the basic characteristics of fine particles and the rules, which they follow. The section then examines the health risks of inhaled particles. Next is explained the influence of particles in the air on the environment, the historical development of the air pollution in the Czech Republic and the most important pollutants. After that is described the legislation, which frames the limits for pollutants suspended in the air. In the practical part is described the methods for calculation the geometry of cascade impactor, the design of three-stage impactor and finally the comparison with professional impactor. The designed impactor was then constructed and tested with wood burning stove as a source of particles.
Characteristics of fan cooling towers
Joska, Jakub ; Milčák, Pavel (referee) ; Pospíšil, Jiří (advisor)
This diploma thesis deals with the problematics of fan cooling towers. The very first part of the text is research, focusing mainly on the theory of cooling and the function of fan cooling towers in general. The following chapter deals with the water resource management of the Dukovany nuclear power plant and the specification of its objects of forced draft cooling towers. The second part describes a computational model created to determine the cooling performance of these towers under the given input conditions. In the following chapters, the results from the computational model are compared with the available data from warranty measurements and with the provided characteristics. The final pages deal with the study of the influence of changes in input parameters on the cooling performance and the research of the behavior of the cooling towers under extreme weather conditions.
The energy demand of an indoor ski slope
Mozola, Ondrej ; Linda, Jakub (referee) ; Pospíšil, Jiří (advisor)
This diploma thesis deals with the issue of energy requirements for operation of indoor ski slopes. The first part is dedicated to research of snow making, cooling and construction methods of ski halls along with the examples of specific projects. In the second part, the aim was to design a ski hall with specific geometry and insulation and then define energy losses of such building. Subsequently, all related energy flows were calculated, which led to the determination of the required cooling capacity. Based on this, the cooling cycle was calculated and the overall electricity demand for the operation of the ski hall during the year was set. In the third part, three options for covering electricity needs are evaluated and at the same time they are compared in terms of financial costs during the year.
Energy intensity of artificial snow production
Křepela, Radim ; Fiedler, Jan (referee) ; Pospíšil, Jiří (advisor)
The presented diploma thesis informs about the origin, history, and benefits of technical snowmaking. It introduces what snow equipment consists of and what processes artificial snow is produced. It also shows the price of tons of snow produced from individual commercially available equipment. In the experimental part, the work deals with the calculation of droplet freezing for various input parameters of water, environment, and equipment. A sample calculation was performed for a falling water droplet from a snow lances. The droplet of discharged water was 0.3 mm in size and had a temperature of 2 ° C. The temperature of the environment was chosen to be -10 ° C. Furthermore, the trajectory of the droplet from a snow gun was determined. In the design, a specific snow pole was designed for the specified parameters, including the speed of the environment. The results were then compared with snow poles available on the market.
Energy supply for greenhouse production
Najbrtová, Zuzana ; Poláčik, Ján (referee) ; Pospíšil, Jiří (advisor)
The import of the vegetable has prevailed in the long run over the own production. In connection with this reality and increasing demand for the food with higher quality the production greenhouse is more often built. The providing heat, cold and electricity for the year-round operation is related to the construction and working of these objects. The theoretical part of this theses describes possible ways how to cover energy consumption for the model greenhouse in Kožichovice, Třebíč region. The heat losses and the year-round heat consumption were stated for the selected model and compared with the exact values from Kožichovice. The following method of energy supply was selected based on the calculated energy consumption - the separate cogeneration unit, cooperation of several cogeneration units, a biogas station, a heat pump and central heating system. These methods of energy supply were subjected to technical and economical comparison.
Impact assessment of the use of hydrogen-enriched natural gas
Galík, Tomáš ; Pospíšil, Jiří (referee) ; Baláš, Marek (advisor)
The Master’s thesis reviews the topic of hydrogen in within European and Czech energy industry. Hydrogen’s usage in gas industry, heating industry and power engineering may play a significant role in meeting European Union’s ambitious goals aiming to reduce emission production. This work identifies specifications of technologies used to produce, transport, and use of hydrogen and their impact on today’s energy systems and safety. The technical, economic, and political context is emphasized. The technical part covers the topic of injecting hydrogen into natural gas and it’s impact on physico-chemical properties of gas. The work analyses concentrations of 0, 5, 10, 15, 20 and 25 molar percent of hydrogen in real composition of natural gas measured on a handover point of transition system. Furthermore, calculations for these mixtures have been done to determine a change in characteristics of a heat exchanger. The results show, that with higher concentrations of hydrogen, the power of heat exchanger rises, while the power of a burner decreases due to lower calorific value of gas mixture. The last chapter follows up on a economical analysis of fuel and emission allowance costs for above-mentioned concentrations of hydrogen in gas mixture. Specific values of combined cycle gas plant Počerady from year 2019 were used for calculations. The results show, that in all of the three considered scenarios of emission allowance price predictions, replacing hydrogen with natural gas did not have a positive economic impact.
Accumulation of electricity from renewable sources
Plíšek, Petr ; Špiláček, Michal (referee) ; Pospíšil, Jiří (advisor)
This diploma thesis deals with the issue of accumulation of electricity produced by renewable sources. The first part focuses on the description of possible ways of accumulation, especially with focus on those methods, that are suitable for renewable energy sources. The next part deals with the design of the accumulation energy in the compressed air for the selected photovoltaic power plant. The necessity of designing a particular method of energy storage, is also its technical and economic analysis, which is the content of the last part of the thesis.

National Repository of Grey Literature : 287 records found   1 - 10nextend  jump to record:
See also: similar author names
41 POSPÍŠIL, Jan
41 Pospisil, Jan
15 Pospíšil, Jakub
41 Pospíšil, Jan
2 Pospíšil, Jaromír
6 Pospíšil, Jaroslav
1 Pospíšil, Jindřich
6 Pospíšil, Josef
2 Pospíšil, Juraj
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