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Methods for determination of hyaluronan
Černá, Lucie ; Venerová, Tereza (referee) ; Pekař, Miloslav (advisor)
This thesis deals with a summary of individual method for determining of hyaluronan concentration, especially in aqueous solutions. Selected methods were compared to their functionality in university workplace. Any functional methods may be used for many purposes in university workplace in research of materials based on hyaluronan. It has been studied usability to assess residual content of hyaluronan in supernatant of gel formed from hyaluronan and surfuctant, in this thesis. We choosed sptectrophotometric methods, especially with UV spectroscopy and IR spectroscopy. Two precipitation methods using alcian blue were also tested. As the most reliable, the least demanding and specific method seems to be the method using IR spectroscopy, thanks to it we are able to determine the concentration of HA from 0.01 %. With this method, it has been found, that if there will be located some amount of HA in supernatant, it will be below the detection limit of assay. The remanining methods were modified to help determine the concentrations of HA, but works only in aqueous solutions. A possible variation for determination of very low concentrations of HA may be the method using ELISA kits. However their cost is higher than the above-mentioned methods.
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Dielectric Properties of Vegetable Oils for Electrical Engineering
Spohner, Milan ; Mejzlík,, Miroslav (referee) ; Mentlík, Václav (referee) ; Liedermann, Karel (advisor)
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.
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Exploitation of Infrared Spectroscopy for Determination of Polymer Admixtures in Cement Composites
Novotný, David ; Hodná, Jana (referee) ; Petránek, Vít (advisor)
In the thesis deals with the possibilities of determining the amount of polymer additives FTIR. Are described in detail various polymeric ingredients which are used in concrete mixtures. Then thoroughly discuss the use of recyclable polymer additives polyvinylbutyral (PVB), its production, the primary use, recycling and subsequent use. Next, I will discuss methods for determining the amount of polymer in the substance. In the experimental part were blended with several samples with different percentage for each polymer. Where we conducted appropriate tests and assessments, and individual samples are briefly described, evaluated and compared.
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Optimisation of Isolation Procedure and Characterization of Amorphous PHB granules
Kratochvíl, Zdeněk ; Obruča, Stanislav (referee) ; Kalina, Michal (advisor)
First artificial PHB granules were prepared under the terms of this thesis. The effect of used PHB solvent, ultrasonic bath temperature and time, solvent evaporation temperature and stabilizing agent nature was investigated using dynamic and electrophoretic light scattering. The most proper parameters were demonstrated at samples which were prepared by dissolving of PHB in chloroform, stabilizing with CTAB or lecithin, ultrasonifying at 35 °C followed by chloroform evaporating at 60 °C. Based on ATR-FTIR and Raman spectroscopy results, it was found out that PHB within the artificial granules were in crystalline form. The native PHB granules were isolated from Cupriavidus necator using either lysosyme, deoxyribonuclease and cell disruption by ultrasonification or digestion with alcalase, SDS and EDTA. Granules obtained by both isolation procedures were characterized by ATR-FTIR, Raman spectroscopy, light scattering techniques and DSC. According to the analyses results, the second mentioned procedure turned out to be more effective for obtaining the polymer in amorphous state. Furthermore, the polymer within granules recovered by using this procedure was thermally more stable. Last but not least, the native PHB granules samples were exposed to effect of acetone, lipase and sodium hypochlorite, assuming that polymer crystallinity should be increased by these chemicals in varying degrees. The highest degree of crystallinity was achieved after their treatment with lipase.
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Diagnostics of plasma chemical deposition processes using organometallic precursors
Sahánková, Hana ; Dvořák, Pavel (referee) ; Krčma, František (advisor)
The aim of this work is diagnostic of plasma chemical deposition thin films based on organometallic precursors. Thin layers have recently become one of the most used methods for surface treatment of materials. They are used as a protective, functional layer, they improve surface properties of materials or increase or reduce the adhesion to various compounds. Plasma polymers are a modern trend in surface treatment technology. Their structure is different from classical polymers. The titanium (IV)isopropoxide was chosen as a monomer example, which is frequently used as a monomer for photocatalytic TiO2 films plasma deposition. These thin films are very promising for the removal of various air and water pollutants and thus they can significantly help in the increase of the environmental quality. Measurements took place on a commercial device Plasmatreater AS 400. The theoretical part describes the background needed for the study and diagnostics of plasma processes and technologies. The optical emission spectroscopy was chosen as a diagnostic method, and thus its principles are outlined in the theoretical part. Infrared spectroscopy and X-ray photoelectron spectroscopy were applied for the diagnostics of prepared thin films and they are also described in the theoretical part. The experimental part contains two sections. The first section is dedicated to the plasma diagnostics by optical emission spectroscopy. Discharge was generated in nitrogen or in the air. Measurements were performed at seven different duty cycles and at two different flow rates for each of the working gases. The molecular bands of nitrogen first negative and second systems, CN violet bands, and atomic lines of oxygen and nozzle elements (Cu, Cr) were identified in the spectra. The titanium lines, and bands of TiO were determined if the precursor was added. Electron temperature was calculated using chromium lines, and electron temperature maps were obtained for continuous mode and pulse mode with duty cycle 70% for nitrogen plasma with 500 sccm precursor flow. Similar discharge maps were also processed using the selected line of titanium (520 nm) TiO band (625 nm) again for the same discharge conditions. Furthermore, the dependences of the same quantities were obtained along the discharge axis as a function of duty cycle in both gases with precursor flow of 1000 sccm. The second part of results brings material analyzes of the deposited samples. The peaks of anatase and rutile have been identified by infrared spectroscopy. Using X-ray photoelectron spectroscopy, we found that our layers contain a significant amount of non-dissociated precursor. Moreover, a large number of radicals, which can interact with atmospheric gases, was determined on the surface. These radicals are removable by annealing or by ion etching. All results obtained during this research can significantly help us to improve the quality of deposited layers and allow us also some prediction of the thin film properties at given plasma conditions. Of course, further experimental as well as theoretical studies should be completed to obtain complete knowledge needed for the wide applications of these layers.
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Optical device for breath CO2 concentration analysis
Škorpík, Daniel ; Milek, Jakub (referee) ; Čmiel, Vratislav (advisor)
This Master's thesis discusses about the measurement of the carbon dioxide concentration in breathing by an optical analyzer using infrared absorption spectroscopy. The method is described with the technical focus on individual components needed for subsequent implementation. A circuit diagram is created to produce Arduino platform devices that serve as hardware to connect and power individual parts and software to create a user environment, followed by a Bluetooth module to transmit measured data to mobile devices where real-time results are presented.
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Exploration of extraterrestrial body impact and UV-driven transformation of atmospheres of terrestrial planets
Knížek, Antonín ; Ferus, Martin (advisor) ; Kabáth, Petr (referee) ; Kopecký, Vladimír (referee)
Keywords: Exoplanets, Earth, Impact, Photochemistry, Infrared Spectroscopy, Atmospheric chemistry Impacts and photochemistry are two very important driving forces for chemical transformation of planetary atmospheres. While strong UV radiation produced by young stars continuously provides a significant amount of energy, impacts are one-time events with far-reaching consequences. Especially important are then impacts on young rocky planets, including the early Earth, because these planets are likely exposed to much higher impact fluxes, commonly called 'heavy bombardment'. This bombardment is the final echo of the turbulent planetary accretion and has prominent significance for planetary environments, e.g., the chemical composition and shape of the planetary surface, the chemistry of atmospheres, aerosol production, and likely the origin of life. Future observations of exoplanets by space telescopes, such as the James Webb Space Telescope or Ariel, as well as ground-based telescopes, such as the Extremely Large Telescope currently under construction in Chile, could determine whether this heavy bombardment represents a common scenario for the evolution of terrestrial planets. Both impacts and photochemistry can be efficiently simulated and studied in laboratory conditions by state-of-the-art methods....
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Comprehensive chemical analysis of blood coatings
Matěcha, Tadeáš ; Kučková, Štěpánka (advisor) ; Kolář, Karel (referee)
This thesis deals with the comprehensive chemical analysis of blood coatings using mass spectrometry and infrared spectroscopy. The theoretical part focuses first on the history of use, properties, and formulations of blood coatings, then on their composition, which is divided into protein and non-protein components, as well as on selected analytical methods used for their identification. In the experimental part, 41 model samples and 2 real samples are evaluated and discussed. Liquid chromatography with tandem mass spectrometry (nano-LC-ESI-Q-TOF MS) was used to identify the protein component in all samples. Determination of the quantitative abundance of each type of protein additive in the blood coatings was performed based on the number of peptides found originating from proteins typical for specific protein additives. Furthermore, it was possible to identify the amino acid sequences that allow to determine the animal origin of the blood used. The non-protein components of all samples were identified by infrared spectroscopy, specifically by the attenuated total reflection and diffuse reflectance techniques. The quantitative analyses based on the change of the intensities of the measured spectra was also discussed. A special chapter is devoted to the identification of animal glue and to the...
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Biomarkers, intravascular ultrasound and near-infrared spectroscopy in the assessment of vulnerable atherosclerotic plaque
Štěchovský, Cyril ; Hájek, Petr (advisor) ; Krajina, Antonín (referee) ; Kaňovský, Jan (referee)
Biomarkers, Intravascular Ultrasound and Near-Infrared Spectroscopy in the Assessment of Vulnerable Atherosclerotic Plaque Abstract The thesis describes pathophysiology of a vulnerable atherosclerotic plaque, detection of the vulnerable plaque in the stenosis of the internal carotid artery (ICA), and optimalization of carotid stenting (CAS) with near-infrared spectroscopy (NIRS) and intravascular ultrasound (IVUS) imaging. NIRS detects lipid core of the vulnerable lipid rich plaque (LRP). We demonstrated safety of NIRS-IVUS imaging during CAS. LRP was detected in one third of ICAs before CAS. Lipid signal was not correlated with plaque morphology (IVUS), biomarkers or clinical variables. CAS caused significant decrease of the lipid signal. Angiography overestimated severity of stenosis of the ICA and vastly underestimated residual stenosis after CAS. Presence of the LRP in the stenosis was neither associated with periprocedural neurological complications of CAS nor long-term adverse cardiovascular events. IVUS identified planimetric features associated with long-term restenosis or stent occlusion. After a median follow-up of 31 months, repeated NIRS-IVUS of the implanted stents showed significant expansion of the stents, diffuse neointimal hyperplasia and further reduction of the lipid signal. We assume,...
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