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Implementace vypařovacího systému pro depozice tenkých vrstev
CIFREUND, David
This thesis focuses on gas dispensing for PECVD proceses in low temperature plasma. Key to succesful depositions is an accurate and stable flow rate of precursor to reactor, where discharges are used for depositions of thin films. Liquid can be also an admixture of the precursor, but it has to be mixed with the carrier gas and finaly evaporated. For this purpose was chosen CEM evaporating system from Bronkhorst High-Tech B.V., which is composed of gas mass flow controller, liquid mass flow controller, evaporating device and control unit. Main goal of this thesis is to implement evaporating system to plasma chemical reactor, calibrate it and do measuring tests.
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Drying of moist materials at low temperatures
Gregor, Jakub ; Neuberger, Pavel (advisor) ; Adamovský, Radomír (referee)
The aim of this work was to develop a literature review on the issue of drying moist materials at low temperatures. The first part is devoted to an overview of drying theory, distribution and classification of dryers and a brief analysis of the most common of them. There is also addressed the issue of the effect of temperature on the dried material and the nature of low-temperature drying.
The second part of the research is concerned with the broadest current method of drying at a low temperature, which is called lyophilisation. There is mentioned principle of the method, the process of drying, processing equipment, methods and examples of activities and overview of key manufacturers.
The third part is devoted to other drying techniques that can be used for effective drying at low temperature and their comparison.
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Special technical solutions in vacuum technology
SZABÓ, Robin
This thesis is focussed on the realisation of various technical solutions for microwave plasma apparatus. The theoretical part focuses on vacuum and general terms that are related. Attention was paid for example to definition of pressure, to pressure and central free track, units of measurement of pressure and their conversions. This part includes the classification of vacuum according to pressure. The next section of the dissertation is concerned with achieving vacuum including a description of rotary oil and turbo molecular pump. Part of the thesis includesa description of plasma microwave apparatus CX22 which was used during realisation of this dissertation. There is also a description of vacuum chamber, gas pump system, system of gas lead, microwave source, evaporator of liquid precursor and mixing apparatus. In the practical section a measurement of physical and technological quantity included. This part covers the inflow of apparatus measurement and temperatures of substrate during plasma process. In the next part there is a description of specific technical solutions suggested by the dissertation author. Amongst suggested technical solutions in this paper there is vacuum isolator, heating system of evaporator pipe, box of an evaporator of liquid precursor, ''gas ring'' and tablet equipment. Vacuum isolator was designed by 3D simulation and serves as a connection to detection technology. Heating of pipes of an evaporator were constructed to improve quality of the plasma process. The box of an evaporator was suggested for maintaining fresh air in a lab. A Gas ring was also designed by 3D simulation and serves as a specially adjusted pipe for bringing vapour of precursor near the substrate. The tablet equipment was constructed for unified preparation of compressed powder cellulosic tablets. Also from the available vacuum pumps, multilevel pumping was constructed that helped achievement of reduced lowest pressure.
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Secondary metallurgy in foundries
Klika, Jiří ; Šenberger, Jaroslav (referee) ; Pernica, Vítězslav (advisor)
The aim of this bachelor thesis is to write a literary research about various methods of secondary metallurgy. In the thesis is described principle of methods and its advantages and disadvantages after installation in the manufactory, especially principle of steelmaking methods. It mainly concerns advantages of secondary metallurgy as degassing, decarburisation, desulphurisation and chemical or heat homogenization of liquid metal in the ladle.
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Decarburisation and degassing of high-alloyed Cr steels under vacuum
Ertelt, Tomáš ; Pernica, Vítězslav (referee) ; Záděra, Antonín (advisor)
The work deals with the investigation of the effects of vacuum degassing and decarburization in high alloyed stainless steel. The reason for this is to increase corrosion resistance and mechanical properties. The theoretical part is devoted to the analysis of options to reduce carbon, nitrogen, hydrogen and manganese at atmospheric pressure and in vacuum. In experimental part there is the description of melting, calculation of conditions facilitating reduction of oxide inclusions as a function of the gas pressure in the furnace and the evaluation of the influence of vacuum on the content reduction of carbon, nitrogen and manganese.
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Precision and dynamics of linear piezo motors
Ilichman, Ondřej ; Vaške, František (referee) ; Houška, Pavel (advisor)
The work deals with the design, control, precision and dynamics of linear piezoelectric motors from PiezoMotor Uppsala AB. The aim of this thesis is to evaluate the applicability of the loaned engine in a mass spectrometer. In introduction‘s section of this work is discussing the design principles of functionality, materials used, procedure and types of piezoelectric motors. It focuses the choice of hardware and design of mechanical assemblies, which could replace the current mechanism with electromagnetic motors. Then we designed and fabricated a test report with hired piezoelectric motor. In NI LabView development environment is created test application for control and measurement. The final section is devoted to a summary of the positive and negative features of the hired piezoelectric motor and evaluation of accuracy and dynamics.
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Development of a linear stage actuator for UHV STM/AFM
Pavelec, Jiří ; Jiruše, Jaroslav (referee) ; Šikola, Tomáš (advisor)
The aim of this diploma thesis is to develop a linear positioning stage for Ultra High Vacuum (UHV) environment. Simple prototypes of the linear positioning stage were designed and incorporated as part of a multiaxis sample manipulator for a UHV Scanning Tunneling Microscopy / Atomic Force Microscopy (STM/AFM). Different types of position encoders and linear guideways are discussed. Implementation of the homodyne interferometer as an optimization tool for a slip-stick based linear stage is described. Scalar diffraction theory is used to model the diffraction grating optical position encoder behavior.
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Bayonet door of pressurized furnace
Brada, Karel ; Anderle, Martin (referee) ; Prokeš, František (advisor)
In this master's thesis a design of door for helium quenching furnace is described. Based on background research, several options for the design have been compared. All calculations were carried out based on structural needs resulting from high pressure gas quenching technology. By the ending of this thesis a mounting procedure and rough cost price estimation is described. Part of master's thesis is also a virtual 3D prototype and a drawing documentation.
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