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Stabilizace pivní pěny pomocí biosurfaktantů / Beer foam stabilization using biosurfactantsJandrtová, Sabina January 2019 (has links)
This diploma thesis focuses on a research of the foam stability of the beer. We specifically observed the influence of ethanol and surface tension on the foam stability, and influence of ethanol and surface tension on the height of the foam. It was observed the influence of the hop acids in non-alcoholic beers. Furthermore, different biosurfactants were added into to the beer to observe better stability of the foam. The theoretical part of this work describes the foam from the physical aspect. There are described fourth key events involved in foam formation. Then it focuses on the beer foam – its structure, substances that influence its behavior and measurement of the foam stability. In this part there are described biosurfactants as well – their characteristics, qualities, distribution and applications. The experimental part is dedicated to the influence of ethanol, surface tension, the amount of iso- acids on foam stability in beer. There is observed the influence of biosurfactants of the foam stability and surface tension, which are added into to the beer. For the measurement of the foam stability was used the Rudin method. Liquid chromatography with DAD detector was used for the measurement the amount of the hop acids. The surface tension was determined by tensiometer. According to the results addition of ethanol changed the characteristics of the foam stability, but it’s not easy to find correlation between the increasing amount of ethanol and its stability. It was found out, that there is connection between the amount of ethanol and surface tension. On the other hand, there is not much connection between the surface tension and foam height. Within the framework of addition of biosurfactants was observed, that these foaming agents interacted the surface tension of the beer (lowering), however these agents accelerated the fall of the beer foam.
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Modifikace povrchu kovových materiálů s využitím elektronového svazku / Surface Treatment Technology of Metallic Materials and its Applications using Electron BeamMatlák, Jiří January 2019 (has links)
Fast deflection is one of the great advantages of an electron beam, making it possible to process a relatively large area at once and also to modify the distribution of the supplied energy. The dissertation deals with surface heat treatment with a focus on the effect of beam deflection on the process. Furthermore, the influence of processing speed and defocusing of the electron beam is studied. The principles of electron beam technology and the summary of surface heat treatment of various materials are presented in the literary part of the thesis. The experimental part is focused on the influence of process parameters on processing in the solid phase, carried out on steel 42CrMo4, and in in the liquid phase, carried out on alloy NiCrBSi. Especially changes in structure, hardness, shape of the processed area and wear resistance are evaluated on processed samples. The results are also evaluated from an energy perspective. Furthermore, an optimum combination of technological parameters is recommended for solid and liquid phase surface heat treatment.
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Elektronová mikroskopie a spektroskopie v plazmonice / Electron microscopy and spectroscopy in plasmonicsHorák, Michal January 2020 (has links)
Tato práce se zabývá mikroskopickými technikami využívajícími elektronový a iontový svazek pro přípravu a charakterizaci plazmonických nanostruktur. Analytická elektronová mikroskopie je představena se zaměřením na aplikace v oblasti plazmoniky. Důraz je kladen na spektroskopii energiových ztrát elektronů (EELS) a katodoluminiscenci. Dále je diskutována výroba plazmonických vzorků pro transmisní elektronovou mikroskopii, přičemž je kladen důraz na litografii iontovým svazkem a na přípravu vzorků za použití chemicky syntetizovaných částic ve vodném roztoku. Hlavní výzkumné výsledky práce jsou rozděleny do čtyř částí. První část se věnuje komparativní studii plazmonických antén vyrobených elektronovou a iontovou litografií. Přestože obě techniky jsou vhodné pro výrobu plazmonických antén, elektronová litografie by měla být upřednostňována před iontovou litografií díky lepší kvalitě výsledných antén a jejich silnější plazmonické odezvě. Antény vyrobené iontovou litografií mají neostré okraje, vykazují výrazné kolísání tloušťky a jsou také silně kontaminovány nejen organickými kontaminanty, ale také rezidui po iontové litografii včetně implantovaných iontů z iontového svazku a atomů titanové adhezivní vrstvy. Ve druhé části je zkoumán Babinetův princip komplementarity pro plazmonické nanostruktury na sérii zlatých diskových antén a komplementárních apertur ve zlaté vrstvě s různými průměry. Komplementarita je potvrzena pro základní plazmonické vlastnosti jako rezonanční energie, ale rozdíly způsobené omezenou platností Babinetova principu jsou patrné například pro prostorové rozložení blízkého pole plazmonových polaritonů. Třetí část shrnuje studii nanostruktur s funkčními vlastnostmi souvisejícími s lokálním zesílením elektrického a magnetického pole. Obzvlášť silné lokální zesílení pole vykazují plazmonické antény tvaru bowtie a diabolo, a to jak ve formě částic, tak ve formě apertur. Naše studie umožnila identifikovat několik módů lokalizovaných povrchových plazmonů v těchto anténách a charakterizovat jejich vlastnosti včetně energie módu, rozložení elektrické a magnetické složky blízkého pole módu, a kvalitativní rozložení uzlů náboje a proudu souvisejících oscilací elektronového plynu. Dále jsme studovali laditelnost energií módů v blízké infračervené a viditelné spektrální oblasti a zaměřili jsme se na Babinetovskou komplementaritu mezi přímými a invertovanými anténami. Poslední část je zaměřena na stříbrný amalgám, nový a velmi perspektivní plazmonický materiál. Změnou velikosti stříbrných amalgámových nanostruktur může být jejich plazmonová rezonance laděna od oblasti ultrafialového záření přes celou viditelnou až po infračervenou oblast. Jelikož stříbrný amalgám je dobře prozkoumán v oblasti elektrochemie, stříbrné amalgámové nanočástice otevírají možnost kombinovat plazmoniku a elektrochemii dohromady.
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Příprava a charakterizace SA vrstev z vinyltriethoxysilanu / Deposition and characterization of SA layers from vinyltriethoxysilaneVeverka, Miroslav January 2008 (has links)
Development of composite material is very much progressive sector and leads to evolution of material with new property. This type of material has one, but important deficiency. It is small adhesion armature to matrix. My study is sight on improvement adhesion the surface by deposition self assembled (SA) monolayer from organosilanes. Property of this layer, like thickness, surface tension, homogenity and wettability, was evaluated by the contact angle measurement and spektroscopical elipsometri.
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Výpočet přídavných ztrát asynchronního motoru / Stray losses calculation of induction machineJirásek, Tomáš January 2013 (has links)
The main goal of this thesis is a determination of an idle stray losses in induction machine and creation calculation program in MATLAB. The stray losses are caused especially by the eddy currents on the surface of stator and rotor, further by a pulsation of these currents owing to the periodical change of air-gap permeance, magnetic induction in stator and rotor teeth and a differential leakage. Value of stray losses are different of engine construction especially by it are scoring insulated, uninsulated, straight or slant.
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Analýza cen zámečnických konstrukcí v ceně objektu / Prices analysis of locksmith constructions included in the price of the construction objectKonečný, Jan January 2014 (has links)
The first part of this master’s thesis, which is more theoretical, contains information relating to prices in general, construction budgets, cost calculation of construction works and materials and costs. In the second part describes the use of materials and their properties, surface treatment and analysis of selected locksmith constructions.
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Buzení a detekce plazmonových polaritonů / Excitation and Detection of Plasmon PolaritonsŠustr, Libor January 2008 (has links)
The diploma thesis is aimed to excitation and detection of surface plasmon polaritons by visible light. First of all, we will briefly remind some basic principles like waves, electromagnetic wave, light on the interface and optical properties of metals. By using these principles we show presence of surface plasmon polaritons states. After the explanation of their properties there will be clearly visible reasons for aplications of the special excitationand detection methods. We will describe especially the prism coupling, periodic grating coupling and SNOM. Two last sections deal with computer simulations and experiments related to these methods. This means we can exemplify some knowledge presented in previous chapters. Results of simulations are compared with the experiment where we study the excitations of surface plasmon polaritons by periodic grating on aluminium surface.
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Lokalizované povrchové plazmony: principy a aplikace / Localized Surface Plasmons: Principles and ApplicationKvapil, Michal January 2010 (has links)
The diploma thesis deals with plasmonic nanostructures for visible eventually near-infrared region of electromagnetic spectrum. At first, there are discussed basic terms which are necessary for description of plasmonic nanostructures and their properties. Then the resonant properties of gold nanoantennas on a fused silica substrate and in proximity of nanocrystalline diamond are addressed. FDTD simulations are used for an assesment of resonant properties and local electric field enhancement of these nanostructures. Possible manufacturing methods of the antennas and techniques for the measurement of their properties are mentioned at the end of the thesis.
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Volba vhodné technologie pro výrobu svařované konstrukce elektrokotle JE 12 a JE 6 / Selection of appropriate technology for the production of welded constructions of boiler JE 12 and JE 6Janás, Milan January 2017 (has links)
The diploma thesis on the selection of appropriate technology to produce the welded construction of electric boiler JE6 / 12 aims to evaluate available production technologies and choose the most suitable of them. Choosing the technologies focuses primarily on those that are available at Slokov. Due to the connection of the welding robot to the production, it is necessary to consider the overall connection of the production and the high accuracy of the production. The individual methods of production, material separation, welding, bending and surface treatment are first theoretically analyzed and their advantages, disadvantages and parameters are summarized. Subsequently, it is practically tested individual technologies for a representative part and it evaluates the achieved parameters and economics of production. With the results obtained, the most suitable technologies are selected. With the selection of technologies, there is a need for a change in design and production parameters. Changes and modifications to the design describe another point. To achieve maximum efficiency and quality of production, a welding robot is used to make welds. The description of the production, modifications and overall design of the robot describes the next point of this work. The last part summarizes the economics of selected production technologies and details the technological process. The aim of the thesis is to design such technologies that will be advantageous from the point of view of the economy and from the perspective of the available possibilities of the company.
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Nové metodiky kombinace hmotnostní spektrometrie (MS) se světlem aktivovaným povrchovým značením, elektronovým přenosem nebo síťovaním (PIXL) / The novel combinations of experimental approaches: mass spectrometry (MS) and photo-induced surface labelling, electron release (PIER), or cross-linking (PIXL)Tuzhilkin, Roman January 2020 (has links)
Countless electron transport/transfer (ET) processes occur in living organisms every day. Therefore, their study is a crucial field of modern structural and functional proteomics. In many cases model proteins like azurin from P. aeruginosa are utilised in experiments. This blue copper protein is favoured due to a characteristic absorbance maximum at 630 nm in Cu(II) redox state of the central Cu atom. During its oxidation to Cu(I) state the A630 value decreases allowing UV-Vis detection of ET reaction progress. We have introduced a structural photoinducible analogue of canonical amino acid Met - L-2-amino-5,5-azihexanoic acid (photo-Met) - into azurin structure to study oligomerization in solution via photo-induced cross-linking (PIXL). Using previously optimised protocols for recombinant expression in E. coli B834 we have inserted photo-Met into azurin moieties: wild type azurin and Az2W mutant where two adjacent W residues with confirmed role in electron hopping across protein-protein interface are present. The incorporation percentage of photo-Met in analysed samples was determined after SDS-PAGE and in-gel protease digestion via MALDI-TOF MS. PIXL was employed to study azurin-azurin interaction and oligomerization under different total concentrations of protein (in range of 15-300 µM). The...
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