The main idea of this thesis is measurements of dielectric materials by using a device Tettex. The thesis is about basic physic properties of dielectric materials. The determination of a dielectric material is considered. The behavior of these materials in electrical fields and reasons, those can have an influence on it, are considered as well. In the text are described measuring methods of chosen parameters of dielectric materials by device Tettex and its functional principles. There are an evaluation of measurements, which were done, and a discussion about achieved results.

This thesis consists of two main parts. The first part is a theoretical analysis, or a literary research, it is focused on the physical properties of the fluid, which have direct impact on the decompression. The aim of the second part is to evaluate the measurement of the forging valve and subsequently simulate the issue by means of CFD. The first simulations were performed for the maximal valve stroke and used for the CFD solver setup calibration. The subsequent analyses dealt with possible openings of the valve. In the final chapter the theoretical impact of the liquid compressibility and of the undissolved air is discussed. The results of the thesis can prove useful for the new valve setting in hydraulic circuit or for possible geometry modification.

Hot melt adhesives (HMA) are a class of adhesives that, unlike solvent-or waterborne counterparts, do not contain organic solvents or other carriers, and are produced and subsequently applied in a molten state. The main components of HMA are polymers, tackifying resins, and a plasticiser. HMA offer a more environmentally friendly option of adhesive materials.  This study was undertaken to investigate the performance of plasticisers based on renewable resources in HMA. Historically, mineral oil-based plasticisers have been used with great success in HMA formulations, offering a performance benchmark. This work selected suitable alternatives from renewable resources, ranging from fully renewable to fully conventional compositions. During the production stage, the compatibility of such plasticisers with the rest of the HMA formulation was studied while rheological methods were used to investigate the impact of different plasticisers on the properties of the final HMA. Adhesive properties were also assessed by loop tack and peel tests on polyethylene terephthalate (PET) and stainless steel (SS) substrates.   It was shown that some of the studied materials from renewable resources could offer a suitable component in the design of a biobased plasticiser, whose performance matched conventional plasticisers, while the ratio of the biobased fraction was up to 70 % and possibly even higher. The findings of this work show the potential of biobased alternatives in making HMA with a higher degree of sustainability. / Smältlim är en klass av lim som, till skillnad från lösningsmedels-eller vattenburna motsvarigheter, inte innehåller organiska lösningsmedel eller andra bärare, och som produceras och appliceras därefter i smält tillstånd. Huvudkomponenterna i HMA är polymerer, klibbgivande hartser och en mjukgörare. smältlim erbjuder ett mer miljövänligt alternativ för limmaterial. Denna studie genomfördes för att undersöka prestandan hos mjukgörare baserade på förnybara resurser i HMA. Historiskt har mineraloljebaserade mjukgörare använts med stor framgång i HMA-formuleringar, vilket ger ett prestandariktmärke. Lämpliga alternativ valdes ut från förnybara resurser, allt från helt förnybara till helt konventionella kompositioner. Under produktionsstadiet studerades kompatibiliteten av sådana mjukgörare med resten av smältlimsformuleringen medan reologiska metoder användes för att undersöka olika mjukgörares inverkan på egenskaperna hos det slutliga limmet. Vidhäftningsegenskaperna utvärderades också genom loop tack test och peel test på polyetylentereftalat (PET) och rostfritt stål (SS) substrat. Det visades att en del av de studerade materialen från förnybara resurser kunde erbjuda en lämplig komponent i designen av en biobaserad mjukgörare, vars prestanda matchade konventionella mjukgörare, medan förhållandet mellan den biobaserade fraktionen var upp till 70 % och möjligen ännu högre. Resultaten av detta arbete visar potentialen hos biobaserade alternativ för att göra HMA med en högre grad av hållbarhet.

The thesis deals with the issue of excise taxes in the Czech Republic and in selected OECD countries over the period 2007-2012 and their impact on resource coverage of the state budget. The theoretical part consists of the basic concepts relating to taxes, their basic structure, including the advantages and disadvantages of various groups of taxes. Main part of this thesis is the analysis of excise taxes in the Czech Republic, Denmark, Germany and the Slovakia which leads to a comparison between these countries. The hypothesis was that the Czech Republic levied excise few. Since this hypothesis is confirmed, the thesis contains a proposal for amendment in excise taxes which of the three possible options is chosen variant of the introduction of new taxes, the taxes on sweets. This part is undoubtedly the greatest benefit of the whole thesis. The work assumes that the introduction of this tax has had a positive impact on the state budget of 6-7 billion Czech crowns.

The dissertation thesis deals with the analysis of prospective environmentally compatible electrical insulating fluids for electrical engineering in relation to their chemical structure. The thesis starts with the overview of the current state of the art and of the latest trends in the use of synthetic and biodegradable natural oils. In the experimental part were studied these oils: mineral oils, rapeseed oil, sunflower oils, soybean oil, methyl oleate, peanut oil, MCT oil, castor oil and other. Dielectric properties were measured using LRC meter Agilent 4980A including dielectric liquid test fixture Agilent 16452A and also by the Novocontrol Alpha-A analyzer. Electrical properties are presented in the frequency range 10 mHz – 1 MHz range in the temperature interval 253 K to 363 K. The work goes on with the study of the suitability of individual oils for lower temperature, including the impact of the chemical structure and formulation on electrical properties.