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Vliv technologie pěstování chmele (Humulus lupulus L.) na kvalitu produktu a využití produktu
KLÍMA, Tomáš
The thesis is focused on the technology of hop growing and the quality of the product of hops, i.e., hop cones. The theoretical part of the thesis defines the hop plant in general and varieties produces in the Czech Republic. It also deals with protection against insect and diseases, fertilization of hops and the technology used in cultivation. Finally, the theoretical part deals with the processing of the hop product. In the practical part, the thesis establishes generally valid rules in hop cul-tivation technology. The effect of NanoFYT Si, which contains SiO2 particles, is then tested in a field experiment. This experiment is then evaluated and discussed with previous research on the effect of silicon on field crops.
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Rheological properties of silicone gels for scar treatment
Khorsand, Ghazal ; Šnejdrová, Eva (advisor) ; Paraskevopoulos, Georgios (referee)
Charles University, Faculty of Pharmacy in Hradci Králové Department of Pharmaceutical Technology Supervisor: PharmDr. Eva Šnejdrová, Ph.D. Student: Ghazal Khorsand Title thesis: Rheological properties of silicone gels for scar treatment The thesis is focused on testing of the flow and viscoelastic properties of the scar treatment silicone-based gels, either commercially available or newly formulated gels under development. The theoretical part deals with the scar formation, silicone in scar treatment, and characterization of the gels. In the experimental part, rotational and oscillation tests were performed using a rotational rheometer. The obtained flow curves were fitted by Newton or Power law models. The shear viscosity, coefficient of consistency, and index of flow behaviour were used for gel characterization and comparison. The highest viscosity revealed in the ScarEsthetique cream, followed by RejuvaSil gel. Surprisingly, the Stratamed scar gel and Scar gel Dr. Max showed the lowest viscosity, even lower than the formulations at the development stage. Despite the name "gel", they behave as Newtonian fluids. The elastic modulus G', viscous modulus G'', and complex modulus G*, phase angle , the gel point, and linear viscoelastic region LVER were selected to describe the viscoelastic behaviour...
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Study of microdefects in Czochralski silicon
Španělová, Klára ; Cába, Vladislav (referee) ; Másilko, Jiří (advisor)
The bachelor's thesis deals with the study of microdefects in Czochralski silicon in cooperation with the company onsemi Rožnov pod Radhoštěm. The main objectiv is to find knowledge about microdefects in Czochralski silicon and their influence on the properties of semiconductor components. The experimental part deals with the characterization of microdefects in Czochralski silicon ingots doped by B, P and Sb and grown in the company onsemi. Specifically, the measurement of radial resistivity is performance using a four-point probe with subsequent conversion to dopant concentration (according to ASTM F 723-99). The radial and axial distribution of microdefects in Czochralski silicon ingots is evaluated using the precipitation test and the OISF test. The position of the vacant-interstitial interface was also detected as part of microdefect study.
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Contamination in semiconductor fabrication
Fojtášková, Helena ; Salyk, Ota (referee) ; Čech, Vladimír (advisor)
This bachelor thesis deals with contamination in the production of semiconductor substrates. It focuses on the efficiency and optimization of wet cleaning processes for monocrystalline silicon and silicon carbide semiconductor wafers. The thesis includes a literature research in the field of semiconductor manufacturing, wafer contamination and wafer cleaning processes. The most commonly studied metal contaminants include iron, copper and nickel, due to their high diffusivity, and therefore these elements were chosen for the experimental part. In the experimental part, wafers were prepared by targeted contamination to verify the effectiveness of the cleaning processes. Contamination analysis was performed using the vapour phase decomposition method combined with inductively coupled plasma mass spectrometry (VPD-ICP-MS) for silicon wafers and total reflection X-ray fluorescence (TXRF) for silicon carbide wafers. Based on the measurement results, the efficiency of the washing processes was evaluated and a procedure for process optimization was recommended.
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Dialysis pump
Švagera, Roman ; Rudolf, Pavel (referee) ; Fialová, Simona (advisor)
Dialysis is still very important treatment process today which needs to be constantly improved. This thesis focuses on the development of a pump for dialysis units, specifically on the pressure pulsations reduction in the rotary peristaltic pump. Using experiments, the problem of peristaltic pumps is explained. With the computational modelling there are proposed design modifications leading to the pressure pulsations reduction.
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Microfluidic systems in silicon technology
Juránek, Dominik ; Fecko, Peter (referee) ; Gablech, Imrich (advisor)
This thesis is devoted to the topic of microfluidics and the functionality of microfluidic devices when working with blood. It further focuses on the use of microfluidic devices to cut blood cells. The first part of this work is dedicated to the theoretical background of microfluidics, it briefly introduces the history of microfluidic devices and the materials used for their integration, moreover, it talks about the methods used when constructing a microfluidic device in a silicon substrate. Lastly, this section includes a description of blood and its composition and some properties important for working with microfluidic devices. The practical part is concerned with the (manufacturing procedure of) creating a microfluidic and testing of device that can cut red blood cells.
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The power of solar radiation falling on a photovoltaic module
Kaliyev, Alexey ; Jandová, Kristýna (referee) ; Křivík, Petr (advisor)
The work is focused on the problem of the solar radiation power impacting on a photovoltaic module. In the theoretical part, the possibilities of using solar energy in renewable energy sources, especially in photovoltaic panels and solar collectors, were discussed and presented. Then the materials on the use of solar energy in these sources were reviewed. In addition, the three main components of incident solar radiation on a photovoltaic module or solar collector were described. Finally, the method for calculating the position of the sun across the sky was discussed and presented, as well as the method for calculating the various components of incident solar radiation on a photovoltaic module.
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Study of various materials for solar cells-
Růžička, Aleš ; Toušková, Jana (advisor) ; Prokeš, Jan (referee)
Sluneční články jsou slibnou a rozvíjející se alternativou ke klasickým zdroj·m elektrické energie. V této práci studujeme r·zné parametry křemíkových a organických slunečních článk·. Ze získa- ných temných voltampérových charakteristik křemíkového článku naměřených při více teplotách byl určen mechanismus transportu náboje v porovnání s teoretickými modely. Taktéž u organické vrstvy polymeru P3CT byl z temné voltampérové charakteristiky za pokojové teploty navržen me- chanismus transportu náboje. Pro měření voltampérových charakteristik slunečních článk· za osvětlení byl použit simulátor slunečního záření. Z naměřených osvětlených voltampérových charakteristik byly určeny výstupní parametry křemíkových a organických slunečních článk·, přičemž byl kladen d·raz na účinnost přeměny sluneční energie na energii elektrickou. Zjištěná účinnost křemíkového článku byla η = 13, 21% a maximální účinnost organických článk· byla η = 1, 51%.
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Optical properties of silicon nanostructures for photovoltaics
Salava, Jan ; Trojánek, František (advisor) ; Žídek, Karel (referee)
Název práce: Optické vlastnosti křemíkových nanostruktur pro fotovoltaiku Autor: Bc. Jan Salava Katedra: Katedra chemické fyziky a optiky Vedoucí diplomové práce: doc. RNDr. František Trojánek, Ph.D., katedra chemické fyziky a optiky Abstrakt: V předložené práci jsou studovány křemíkové nanokrystaly umístěné v SiC matrici - jednotlivé vzorky se odlišují přidáním dopantu (boru) do příslušné vrstvy struktury během depozice metodou PECVD a pasivací vodíkem. Křemíkové nanokrystaly jsou významné zejména tím, že oproti své objemové verzi vykazují účinnou fotoluminiscenci a absorpci ve viditelné oblasti spektra. Změnami parametr· při přípravě lze ladit jejich vlastnosti s ohledem na konkrétní aplikaci. Základní myšlenka integrace křemíkových nanostruktur do solárních článk· spočívá ve zvýšení účinnosti konverze slunečního spektra kombinací několika tenkých vrstev s nanokrystaly a objemového Si článku tak, aby každá vrstva sluneční cely absorbo- vala určitou část spektra. Procesy, které se v těchto strukturách dějí krátce po excitaci nosič· náboje, však stále nejsou zcela popsány. Cílem práce je charakterizace těchto jev· metodami ča- sově rozlišené spektroskopie. Dalším úkolem je popsat vliv dopování jednotlivých částí materiálu a jeho pasivace ve vodíkové atmosféře na chování fotoexcitovaných nosič· a intenzitu...
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Study of optical nonlinearities in semiconductors and semiconductor nanostructures
Chlouba, Tomáš ; Trojánek, František (advisor) ; Filip, Radim (referee) ; Herynková, Kateřina (referee)
In the main part of this thesis I study the relaxation mechanisms of charge carriers in silicon nanocrystals in SiO2 matrix. One of the potential applications of these structures lies in photovoltaics, specifically in construction of all-silicon tandem solar cells. I studied the dynamics of carriers in these structures by methods of ultrafast spectroscopy which helped to unravel the microscopic behaviour of carriers, their transport, localization etc. Furthermore I investigated the doping of such structures as the technology of doping is crucial for manufacture of pn- junctions which are the core component of solar cells. At the end I delve into the dissipative Jaynes-Cummings model by mathematical modeling and theoretical calculations which describes among others microlasers and as such comes under a field of cavity quantum electrodynamics.
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