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Properties of polymer modified bitumen for warm mix asphalt
Zábranský, Ivo ; Koudelka, Tomáš (referee) ; Dašek, Ondřej (advisor)
The Diploma thesis is focus on polymer modified bitumen for warm mix asphalt. The theoretical part of the thesis describes additives which influence the properties of bitumen for their use and reduction of production and service temperatures. Further, the theoretical part describes the conclusions from the researches. This part also describes empirical and functional tests of bituminous binders. The practical part presents the results of individual tests. Tests were performed on samples of non-aged, aged by RTFOT and RTFOT + PAV methods. The results of the work and the assessment of the suitability of bituminous binders are summarized at the end of the thesis.
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Ageing of asphalt binders and mixtures
Štěpanovský, Vlastimil ; Komenda, Radek (referee) ; Hýzl, Petr (advisor)
Diploma thesis is particularly focused on ageing of asphalt mixtures and asphalt binders. In the theoretical part an array of methods simulating short term and long term ageing consequently is introduced. The main objective of the practical part was to carry out the long-term ageing test method BSA (Braunschweiger Alterung). Thereafter, specimens testing for stiffness properties according to CSN EN 12697-26 were made. After conducting the measurement on those, asphalt binder was extracted and processed to follow-up testing. The testing consisted of a range of methods – Penetration CSN EN 1426, Ring and Ball test CSN EN 1427, Determination of the Frass breaking point CSN EN 12593, Determination of complex shear modulus CSN EN 14770 and Dynamic viscosity using a dynamic shear rheometer (DSR). The given results were assessed in the last part in order to evaluate the rate of the binder degradation caused by the method BSA.
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Physical-chemical property characterisation of thin reflective layers on silicon substrates
Rozsívalová, Zdeňka ; Studýnka, Jan (referee) ; Krčma, František (advisor)
This thesis deals with surface analysis and characterization of optical features of thin films created by hexamethyldisiloxane (HMDSO) plasma polymerization on silicon wafers. The RF plasma industrial deposition equipment was used for the thin layers formation. These thin films serve as protective coatings on the reflective layer in the car light or solar panels. Theoretic part gives basic information about plasma, its occurrence, features, diagnostics and applications. Thin layers, their production and characterization are discussed here, too. Theoretic description of monomer material (including the group of other organosilicones) is also presented here. The FTIR spectroscopy and elipsometry are mentioned as the main methods for thin films characterisation. Because material during its practical use degrades due to external conditions, the influence of them on the thin layer properties is studied using the accelerated aging of created films. Industrial deposition chamber AluMet 1800V made by Leybold Optics, Ltd. installed in Zlin Precision company was used for the thin films production. Thin films were created under different conditions that were selelected near to the real conditions used in technology. Various applied powers (2-5 kW) were used for the deposition under different monomer flows. Further, the influence of oxygen addition on the created film properties was investigated. The deposition process was monitored by optical emission spectroscopy. The spectrometer Jobin Yvon Triax 320 with CCD detector was used. The selected part from every samples set was exposed by UV radiation (48 hours at radiation density of 0.68 W/m2 at 340 nm) to simulate the probable conditions during the layers real use. The surface properties were investigated by measurement of reflected light spectral intensity in the visible range at different angles. The angle between incident and reflected beam was varied in the interval of 40 - 150° with 10° step. The influence of sample preparation conditions as well as their aging effect was studied at the selected angles. Spectral reflectance doesn´t depend significantly on applied discharge power and oxygen addition. The significant shift of reflectance into the red part of spectrum was observed at UV exposed samples more or less independently on the applied discharge power of monomer flow rate. Addition of oxygen during the deposition suppresses this effec significantly. Characterization of thin layer structure was done by FTIR spectroscopy. No significant changes were observed in the structure at different discharge powers of monomer flow rates except total absorption intensities that are proportional to the layr thickness. The oxygen addition, of course, changes the structure significantly. These results are only preliminary because the layers were very thin (deposition conditions were near to the common process standard) and thus the signal/noise ratio was relatively low.
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WETTABILITY OF PCB SURFACE FINISHES
Minář, Jan ; Jana, Toulová (referee) ; Starý, Jiří (advisor)
This bachelor’s thesis with measuring of wetting characteristics by the wetting balance method for samples of different surface finishes from the firm Gatema. It deals with influence of the isothermal aging and reflow processes on wetting characteristics of surface finishes ENIG, HAL and immersion tin. The influence of intermetallic layer on the overall wettability is studied in case of the surface finish of immersion tin. Also deals with the wettability of the nickel layer, after stripped off gold, in case of the surface finish of ENIG.
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Senior citizens home Sokolnice
Vávra, Vít ; Šindlar, Jiljí (referee) ; Marek, Jiří (advisor)
The area of the former barracks lies near Sokolnice falling into the periphery of Brno. It is a picturesque village that has a rich history. The barracks are located on a hill called Stará hora, there are several cadastral areas. Near the building, we can find a radar that manages the nearby Brno airport, or the Peace Mound built on the Prateck Hill, soldiers fall to remembrance. The design principle was based on the given operation and its related functions. Dining room, rehabilitation, barber, pedicure, buffet and, last but not least, a multifunctional hall with a small library. The destruction of the unnecessary transformer station and the replenishment of the mass was a logical solution to the situation. It is an assembled reinforced concrete frame 8x8m. Inside the half-block we find a terrace with a pool, which is trying to create a specific microclimate and humidify the surroundings. The pool also serves as a retention tank and the house effectively manages rainwater. Within the lifetime, because of the corrosion of reinforced concrete and the unclear condition of the structure, I designed the exterior cladding to demolish and build a new cladding, a brick made of ceramic blocks. The house is designed in a minimalist spirit and cooperates with the greenery in its surroundings. Especially in long-distance views of integration into the landscape, this greenery is valued. The spirit of place in heavy air bears a strange whiff of dragging death that, when thinking about the history of a place, froze and freezes ... so perhaps while resting before the last journey ... that house discourages and breathes a little life into dying ...
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Analysis of multistress ageing on dielectric spectras of materials
Kučera, Miroslav ; Frk, Martin (referee) ; Rozsívalová, Zdenka (advisor)
Diploma thesis treat of effect of thermal, electrical and combined (thermal electrical) stress on electrical characteristics of insulation material ISONOM NMN which is used as a slot insulation in electric motors. To monitor the stress is used the method of dielectric relaxation spectroscopy. Under examinations are the resultant dielectric spectra which constitute the frequency dependencies of components of complex permitivity. Compared are the effects of particular stresses on dielectric spectra of surveyed insulative material.
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Influence of
Dostál, Filip ; Dašek, Ondřej (referee) ; Hýzl, Petr (advisor)
The diploma thesis is focused on polymer modified binders with different polymer doses. The theoretical part describes the history of the use of bitumen, the extraction of bitumen from oil and behavious of the polymer type SBS/SB, which is used in the diploma thesis on modified binders. Further, the theoretical part describes the empirical and functional tests of bitumen binders. In the practical part the results of indidual tests are presented and compared with the standard ČSN 65 7222-1. At the end of the diploma thesis are summarized results of work and evaluation of binders with the best achieved properties.
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FET aging model
Novosád, Jiří ; Legát, Pavel (referee) ; Semiconductor, Aleš Litschmann, ON (advisor)
This work deals with problems aging of unipolar transistors. In theoretical parts are described the mechanisms which causing aging unipolar transistors and way leading to the restriction the change of parameters in time. The measurement and data evaluation was built on theoretical knowledge. The model of aging FET is a result of this works; it is creating extraction of data from measured data. Finally, the degradation constants are evaluation from this data. This FET aging model is easy to use in simulators of electronics circuits including aging simulations (e.g. ELDO).
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Analysis of mechanical properties of plastic samples produced by 3D printing technology
Jiroušek, Jan ; Joska, Zdeněk (referee) ; Sedlák, Josef (advisor)
The master's thesis deals with the determination of mechanical properties of materials used for 3D printing (PLA, PETG, ABS, ASA). The theoretical part contains characteristics of polymer materials and describes testing of mechanical properties and additive technologies. In the experimental part, the standardized samples produced by the technology Fused Filament Fabrication were analysed using mechanical tests (tensile test and hardness test). Some of the examples were exposed to the selected factors of degradation. Selected parameters from mechanical testing (tensile strength, modulus of elasticity in tension, elongation and Shore hardness) were statistically processed. The conclusion of the thesis evaluates the impact of the factors of degradation on particular materials and compares them subsequently.
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Simulation of asphalt mixture ageing in laboratory
Staňková, Michaela ; Hýzl, Petr (referee) ; Dašek, Ondřej (advisor)
The bachelor thesis deals with the issue of ageing of asphalt binder and asphalt mixture. Asphalt mixtures of asphalt concrete type containing 50/70 paving bitumen were collected for the purposes of this thesis. Test specimens were prepared from the mixtures according to ČSN EN 12697-30+A1 standard. The test specimens were aged in a laboratory oven. Changes in properties caused by ageing were compared using particle loss of porous asphalt specimen according to ČSN EN 12697-17+A1 and the indirect tensile strength of bituminous specimens according to ČSN EN 12697-23 standard.
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