|
|
Waterjet cutting of material
Veselý, Radek ; Foldyna, Josef (referee) ; Habán, Vladimír (advisor)
This bachelor thesis describes principles of utilization of high-speed liquid jet for material machining. In the first part, basic classification of liquid jets and brief description of devices for generating high pressure liquid is presented. Next, using of continuous jets is discussed. Main scope of this work is oriented at the use of so-called pulsed jets, especially at ultrasonically modulated ones. Break-up of ultrasonically modulated high-speed pulsed jet into single pulses, impact of such pulse on the surface of disintegrated material and subsequent erosion in the impact area are described. The comparison of efficiency of modulated and continual water jets is summarized in the last part of the thesis.
|
|
|
Hydrogen production
Poláčik, Ján ; Fiedler, Jan (referee) ; Pospíšil, Jiří (advisor)
The thesis deals with water electrolysis focusing in particular on pulse electrolysis. The theoretical part characterizes hydrogen and its properties as well as the ways of its use and storage. It also analysis various methods of hydrogen generation. It examines in details water electrolysis and its energetic and chemical balance. There is also an evaluation of water electrolysis efficiency and its improvement followed by pulse electrolysis description. Laboratory equipment for direct current and pulsed direct current hydrogen production are suggested. Theoretical expectations are tested experimentally. Finally the thesis presents the results of measurements, compares and summarizes the data. It points out the contribution of this type of electrolysis with its effectiveness. It proposes uses of electrolysis and the subsequent research.
|
|
|
Water jet cutting of material
Jáchym, Jan ; Fialová, Simona (referee) ; Habán, Vladimír (advisor)
This bachelor thesis describes principles developement and usage of high - speed water jets for cutting. In the first part, it features description water jet cutting technology and its application, basic parts of high pressure system and sorts of generators pressure. In the second part, it divides water jet according to discreteness in time and chemical constitution. In the third part, it deal with studies usage so - called pulse jets, especially at ultrasonically modulated ones. It is described mechanism rise and break up of modulated high - speed jet on individual pulses.
|
|
|
Legumes and their importance in nutrition
Hledíková, Zuzana ; Dostálová, Jana (advisor) ; Chrpová, Diana (referee)
The master's thesis deals with the characteristics of legumes, their consumption in my country and in the world, different options of preparation and mostly their composition and influence on health. Legumes are an important source of plant based protein, complex carbohydrates, fiber, vitamins, minerals and other components, that might be regarded as less desirable due to possible interactions with food nutrients and gastrointestinal issues. The amount of some of these substances could be reduced by following treatment and on the other hand even these antinutrients can be benefitial. Last but not least legumes are grtting more important in conection with the environment and other alternative diets such as vegetarianism and veganism, where legumes are important as a protein source instead of animal based sources. The practical part consists of a survey with the aim to determine knowledge about legumes, preference and frequency of their consumption and with linking characteristics of students of medical faculties as a part of the population, that is preparing for work conected with human health. The second part of the practical part was a sensory analysis of leguminous dishes. There, the acceptance of their hedonic parameters was determined and their nutritional analysis was made. From the results of...
|
|
|
Hydrogen production
Poláčik, Ján ; Fiedler, Jan (referee) ; Pospíšil, Jiří (advisor)
The thesis deals with water electrolysis focusing in particular on pulse electrolysis. The theoretical part characterizes hydrogen and its properties as well as the ways of its use and storage. It also analysis various methods of hydrogen generation. It examines in details water electrolysis and its energetic and chemical balance. There is also an evaluation of water electrolysis efficiency and its improvement followed by pulse electrolysis description. Laboratory equipment for direct current and pulsed direct current hydrogen production are suggested. Theoretical expectations are tested experimentally. Finally the thesis presents the results of measurements, compares and summarizes the data. It points out the contribution of this type of electrolysis with its effectiveness. It proposes uses of electrolysis and the subsequent research.
|
|
|
Water jet cutting of material
Jáchym, Jan ; Fialová, Simona (referee) ; Habán, Vladimír (advisor)
This bachelor thesis describes principles developement and usage of high - speed water jets for cutting. In the first part, it features description water jet cutting technology and its application, basic parts of high pressure system and sorts of generators pressure. In the second part, it divides water jet according to discreteness in time and chemical constitution. In the third part, it deal with studies usage so - called pulse jets, especially at ultrasonically modulated ones. It is described mechanism rise and break up of modulated high - speed jet on individual pulses.
|
|
|
Waterjet cutting of material
Veselý, Radek ; Foldyna, Josef (referee) ; Habán, Vladimír (advisor)
This bachelor thesis describes principles of utilization of high-speed liquid jet for material machining. In the first part, basic classification of liquid jets and brief description of devices for generating high pressure liquid is presented. Next, using of continuous jets is discussed. Main scope of this work is oriented at the use of so-called pulsed jets, especially at ultrasonically modulated ones. Break-up of ultrasonically modulated high-speed pulsed jet into single pulses, impact of such pulse on the surface of disintegrated material and subsequent erosion in the impact area are described. The comparison of efficiency of modulated and continual water jets is summarized in the last part of the thesis.
|
|
|
Measurements of nonlinear optical phenomena generated by femtosecond laser pulses. Autocorrelator
PAVLÍČEK, Martin
Ultrashort intensity optical pulses are often used in science, physic or med. Therefore I will be make work, which examine these pulses. In this work I measuring width of ultrashort laser pulses. Load of this work is a make experimental measuring system, which can measure these pulses. The light is propagating as electromagnetic waves. This waves contains electric and magnetic particles. I using light characterized by electric particle. In this case, light is propagating as femtosecond laser pulse. This laser pulses are generating in modelocking lasers, they are based on phase synchronization of longitudinal modes. If pulses are propagating through anisotropic medium (nonlinear crystal), can arrive phenomenon called frequency doubling (second harmonic generating). Further in this work I explore expansion of pulse, propagating through the medium. This phenomenon called group velocity dispersion. I´m measuring the pulse width by two methods. Both of these methods are compare. Addition measure is pulse spectrum measure. From these results are calculated quality of laser source INTEGRA-i. From theoretical formulas are calculated possibility values. Theoretical and practical results are compare on end of this work.
|
guest ::
