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Deposition of environmental dust particles
Bělka, Miloslav ; Pospíšil, Jiří (referee) ; Jedelský, Jan (advisor)
This work is aimed at deposition of fibers, which are able to penetrate deeper in the human respiratory airways and cause health hazards. Opening chapters are dedicated to classification of aerosols, human lung anatomy basics and methods for measurement of micrometer-sized aerosols. An experiment was carried out to investigate the deposition of fibers. Fibers were delivered into the silicon cast of the human airways and data of deposition fraction and efficiency were acquired. A new method was established to acquire the data. This method works on a principle of image analysis. Results of the new method were compared with a standard method, which follows a methodology NIOSH 7400.
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Optimization of thin films of metal oxide materials
Vítek, Jiří ; Šimonová, Lucie (referee) ; Šubarda, Jiří (advisor)
This thesis is focused on the description of the method of reactive sputtering of thin films. Currently, there are many ways how to create thin films and there are many applications of thin films in various industrial sectors. In this paper at the first are listed the issue of thin films, followed by an overview of the deposition techniques and of the chemical analysis of deposited thin films. It also describes the four-point measurement method of sheet resistance, mechanical test of adhesion and optical properties. At the end of the theoretical part are described the material composition of the deposited films. The goal of the practical part is to optimize the deposition process of the mixed layer of indium tin oxide (In2O3: SnO2) and contribute to the overall understanding of the influence of annealing on the layer. There were created six series of samples with that applied layers. First, the work focused on examining of the influence of annealing on the throughput in the whole measuring range, and then comparing the series due to the transmittance in the visible light spectrum. Furthermore were compared the value of sheet resistance of unannealed and subsequently annealed samples.
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Studies of molecular beams of organic materials
Maniš, Jaroslav ; Průša, Stanislav (referee) ; Mach, Jindřich (advisor)
This bachelor's thesis deals with assembling of low-temperature efussion cell which is suitable for deposition of organic materials. The calibration of operating temperature of effusion cell is performed. Depositions of organic semiconductor material are realized. Morphology of surface of thin film is studied in AFM and SEM microscope. In the paper background research on the utilization of organic materials in semiconductor industry is presented.
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Tools Made from Cemented Carbide
Opršál, Ladislav ; Osička, Karel (referee) ; Kalivoda, Milan (advisor)
The thesis focuses on cutting tools made of both coated and uncoated cemented carbides. The first part of the thesis deals with the division of materials used for the production of the tools. The second part of the thesis introduces uncoated cemented carbides, special attention being paid to the labelling, production and properties of such compounds. The third part of the thesis presents coating deposition techniques and examines the properties of coating layers. Coating layers are produced using two different methods – CVD and PVD. The last part of the thesis compares the properties of the cutting tools (e.g. their cutting values) produced by the companies Pramet Tools, Sandvik – Coromant and Seco Tools.
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A method for the solution of non-spherical (fiber) particles deposition by means of the Fokker-Planck equation for ODF in a laminar flow
Kopečková, Barbora ; Knotek, Stanislav (referee) ; Jícha, Miroslav (advisor)
The Bachelor's thesis deals with a deposition efficiency for a fibers by various mechanisms of a deposition. It explains deposition efficiency by diffusion, by sedimentation and by impaction. The implementation of Peterlin's analytical solution for calculation of the ODF, which is used for individual efficiencies solution, is also mentioned. Afterwards, the thesis summarizes formulas for calculation of particular efficiencies derived for spherical particles and recomputation appropriate parameters for fibers. The purpose of the thesis is to create graphs, which illustrate deposition efficiencies dependence by various mechanisms on the aspect ratio of fibers. Another goal is the graphs creation, which shows juxtaposition for various breathing modes for given deposition mechanisms. The software MATLAB is used for the whole calculation process and graphs plotting.
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Vyhodnocení koloběhu hořčíku ve smíšeném porostu v oblasti Drahanské vrchoviny
Hartl, Vít
Magnesium is one of the major biogenic elements for both - plants and animals. It is involved in many metabolic processes concerning plants, and most importantly magnesium is associated with photosynthesis. This bachelor thesis evaluates the flows and stocks of magnesium on the level of the forest cover and of the soil in the Drahanská vrchovina Upland (location: 49 ° 28'2 .976 "N, 16 ° 41'18 .181" E) in a mixed forest cover (beech, spruce, silver, fir) on the modal oligotropic Cambisol of the silver/beech forest vegetation zone at the age of 130 years at an altitude of 610-620 m above the sea level. In the forest cover, there is accumulated 23 655 kg.Mg.ha-1 in the overlying humus and soil. The precipitations in open area make 0.93 kg.Mg.ha-1.year-1. The soil receives annually 2.55 kg.Mg.ha-1 by throughfall precipitations. The input of magnesium by the seepage waters under A0 horizon (forest floor) is calculated in the amount of 2.37 kg.Mg.ha-1. The obtained results are extending the knowledge of the flow and the occurrence of magnesium in the soil in mixed forest covers.
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Deposition of the thin films for applications of advanced oxidation processes using metal dopants
KRAJČOVIČ, Jan
The aim of this diploma thesis is deposition of TiO2 thin films onto different types and sizes of substrates, and some of these layers dope by iron or silver. During the work was range of TiO2 layers created using a method of physical vapor deposition namely magnetron sputtering. For these processes was chosen the Dreva ARC 400 Hard Material Coating Plant device. The main aim of these depositions was to attempt to create TiO2 thin films on a substrates of larger surface than its in average laboratory processes usual. For this purpose were TiO2 layers deposited onto square glass plates of side length 10 cm. For comparsion and analysis were also as a substrates used microscope slides and fragments of silicon wafers. These substrates were used for testing of photocatalytic activity and on surface morphology (SEM). The theoretical part of this thesis aims to a methods of deposition TiO2 layers and their characteristics. In the experimental part is the used coating equipment and parameters of each deposition process described. Further the characteristics and results of individual experiments are described.
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