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Analysis of mechanical loads of selected structural parts of the excavator during operation
Busta, Michal ; Maňas, Pavel (referee) ; Vosynek, Petr (advisor)
This thesis is focused on the issue of computational modeling of soil harvesting while using the compact excavator from the company DOOSAN BOBCAT EMEA s.r.o.. The solution consists in creating two computational models in Rocky DEM and Ansys Mechanical. Rocky DEM software is used to solve the disconnection of soil by excavator components using the discrete element method. The outcome includes courses of forces and moments during the particular time of the individual joints of the model that was used. The obtained courses are then applied as an external load to the joint of a selected structural part of the analyzed model using a kinematic model in ANSYS Mechanical. The kinematic model consists of simplified geometry models of individual parts of the excavator arm, and a more detailed geometry model of the analyzed part of the arm. All the parts are connected to each other by rotational bonds representing joints. A static structural analysis of the mechanical stress is performed in ANSYS Mechanical for the prepared model during the simulated process. Finally, the selected structural part is assessed with respect to the elastic limit and fatigue strength.
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Atmospheric particles and their measurement
Kantor, Radek ; Elcner, Jakub (referee) ; Bělka, Miloslav (advisor)
The aim of this work is to find out what aerosols are, what properties they possess and how they can be measured. In today’s age, the term particles in the atmosphere, is highly talked about because it is known, that particles in the air can be inhaled and cause health problems. By measuring properties of particles from different sources, we can find out the danger level of such particles. One sample was measured by several different techniques and analyzed. Thanks to this analysis we can determine size distribution of particles and then their possible danger.
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Particle Systems
Bedecs, Jakub ; Maršík, Lukáš (referee) ; Kajan, Rudolf (advisor)
This bachelor's thesis deals with the implementation of particle systems with the usage of calculation power of GPU. The purpose of this work is to describe all important facts about the particle systems construction and to show up various possibilities of its usage. It analysis the abilities of modern shaders and their usage for calculation of particles movement. The basis of this work is the analysis of the implemented application, which is able to dynamically change all parameters of the system.
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Preparation and application particles from copolymer of P(3HB-co-4HB)
Ostanina, Kseniia ; Sedláček, Petr (referee) ; Obruča, Stanislav (advisor)
This bachelor thesis deals with preparation of particles from poly(3-hydroxybutyráte-co-4-hydroxybutyráte). Copolymer was dissolved in acetone and then the solution had been dosed into the anti-solvents. Acetone and anti-solvent are perfectly miscible. Theoretical part focuses on the properties of the copolymer, its production and potential use in medical applications. In the experimental part the copolymer was dripped into selected anti-solvents by syringe and pipette above and below the surface of anti-solvent. The following anti-solvent were chosen: water, methanol, dimethylsulfoxid (DMSO), 50 % acetone-water, 75% acetone-water, 50 % methanol-water, 75 % methanol-water mixtures. There were three copolymers used with different compositions of 4HB units (63 %, 87 % a 33 %). Copolymer composition was analyzed by gas chromatography. Copolymers were prepared by bacterial strain Aneurinibacillus sp. H1. Due to the results particles of size approximately 100-500 nm can be prepared by methods described in this work. The produced particles can be successfully used in medical applications.
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Possibilities of encapsulation of particular types of macromolecules and bacteria
Kapar, Jiří ; Obruča, Stanislav (referee) ; Márová, Ivana (advisor)
Presented diploma thesis is focused on testing encapsulation methods of enzymes and probiotic bacteria. In the theoretical part a summary of different encapsulation techniques used in food industry is given. Further, materials for encapsulation, above all polysaccharides are presented. Next, some procedures of encapsulation of biopolymers and microorganisms – mainly enzymes and probiotic cultures are discussed. In the experimental part methods for preparation of several types of particles based on polysaccharides and liposomes are introduced. Particles were used for encapsulation of selected hydrolytic enzymes and probiotic strains Bifidobacterium breve a Lactobacillus acidophilus. The encapsulation effectiveness was evaluated by analysis of total proteins and enzyme activities. Particles sizes and their stability in water, in selected model foods and model body fluids were observed, too. According to results obtained in this work it was found that encapsulation of enzymes into polysaccharide particles were succesfull in all types of particles (encapsulation effectivness was more than 50 %). Polysaccharide particles showed a very good stability in body fluids as well as in model foods. As the most suitable materials for enzymes encapsulation chitosan and liposomes were found. Polysaccharide particles were used also for the encapsulation of microorganisms. The stability of particles with lactic acid bacteria was similar to particles containig enzymes, very good stability was verified aslo in model foods and model body fluids. Encapsulation enables long-term stabilization of biologically active compounds as well as posibility of their transport and controlled releasing in gastrointestinal tract. Encapsulation of probiotic bacteria could preserve their viability and long-term survival until the product expiration date. Thus, encapsulation is one of the most promissing procedures for production of foods and food suplements of great quality and high additional value.
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Numerical modeling of free ions movement
Sukup, Luboš ; Steinbauer, Miloslav (referee) ; Fiala, Pavel (advisor)
This work deals of movement free ions in environment, which is affected by acting of electric field, magnetic field and their interacting. In first part is work focused on numerical methods, which solve exemplars situations. Here is important to properly choose adequate numerical method. Second part of this work interprets influence of these fields on the ions and influence of environment on final motion. The last experimental part is focused on model of cylindrical capacitor as a sensor, which models nonuniform electric field.
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Targeted Preparation of Composite Based on PP with Inorganic Micro-, or Nanofiller with Different Adhesive Interlayer
Dombková, Julie ; Krčma, František (referee) ; Nezbedová, Eva (advisor)
The diploma thesis studies composite of PP and filler particle. As a particle filler was used commercially available CaCO3 (SOCAL 31). The submitted thesis had a goal to find new approaches and technologies of filler surface treatment in order to improve properties of composite materials. The plasma discharge behind static pressure was used for the surface treatment of the fillers. These fillers were afterwards analyzed by using of sedimentation analysis, turbidimetry, infra-red spectroscopy (FT-IR), X-ray diffraction analysis (XRD), scan electron microscopy (SEM), transmission electron microscopy and particle size distribution by laser diffraction. The composites with various volume parts of the fillers were prepared in PIB and studied by short-time tests. Furthermore, the influence of an adhesive layer on fracture mechanical properties of prepared composite was study. Regarding to experimental demand, there was not possible to realize long-term mechanical properties.
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Device and methods for testing clean rooms
Bojanovský, Tomáš ; Kolbábek, Antonín (referee) ; Štětina, Josef (advisor)
In the introduction of the thesis there is described main information about clean rooms that influences the way of measurement and evaluation of these rooms. Then there is a summary of instruments that are used with testing and controlling mentioned rooms. It is primarily a case of device for measurement of concentration of particles in the air that are produced by several firms nowadays. Lighthouse Worldwide Solutions is mentioned as the main producer of these devices. Its three basic types are described in the work. In the next chapter there is the list of other firms occupying this technology and their products. Finally, particular instruments are compared with the regard of different requirements that are placed on them.
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Cyclone trap for very small particles
Pažourek, Josef ; Baláš, Marek (referee) ; Pospíšil, Jiří (advisor)
This thesis deals with really small cyclone separators which could be used for a flue gas purification. The search section discusses particle formation in combustion, their characteristics, any other flue gas cleaning options and last but not least, a cyclone separator where is the effort to understand all the influences that contribute to a cyclone’s resulting separability. The Experimental section analyses a calculation of the cyclone and theoretical separability, a verification of this separability using a cyclone created by a 3D printer. On the one hand, the verification was made by gravimetric analysis which is intended for a bigger particles, on the second hand, it was made using the PALAS which is aimed at particles in µm. There is also a comparison of theoretical and measured values in this section.
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