|
|
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.
|
|
|
The influence of the quality of articulation UHMWPE inserts on the lifetime of joint replacements
Fulín, Petr ; Pokorný, David (advisor) ; Koudela, Karel (referee) ; Gallo, Jiří (referee)
This thesis focuses on the introduction with the problems of high molecular weight polyethylene (UHMWPE) in orthopedics in the first part. It discusses the history, properties and processes that lead to the failure of UHMWPE joint replacement components. The experimental part validates the hypotheses expressed. It acquaints readers with the experimental verification of the effect of different types of sterilization on the oxidative stability of laboratory prepared samples and explanted UHMWPE joint replacement components using methods of infrared microscopy, electron spin resonance, mechanical tests and tests of microhardness. Other experimental measurements on a large set of explanted components of hip and knee total joint replacements validates the hypothesis that the amount of oxidative damage affects the lifespan of joint replacements. The third part of the experimental study maps the degree of oxidative damage in different places of the hip and knee joint replacements. In the final part we experimentally demonstrate the fact that the rate of oxidative damage has an effect on supramolecular structure of the UHMWPE. From the above experiments are concluded clearly defined recommendations for clinical practice, which should lead to extend the lifespan of total joints replacements in orthopaedics....
|
|
|
Výskyt metanolu ve víně a lihovinách a jeho působení na lidský organismus
Osičková, Klára
The bachelor thesis "The occurrence of methanol in wine and spirits and its effect on the human body" describes the basic components in wines and spirits and the influence of individual substances on the overall quality of the product produced. The main topic of the work is methanol, which includes the chemical and physical properties of methanol, methods of determining its content and its formation in alcoholic beverages. The next part of this thesis deals with the effect of methanol on human organism. First it describes its effects in the body, symptoms of methanol poisoning and last but not least the provision of first aid in case of suspected poisoning by this substance. The work describes how to avoid poor quality alcohol and thus poisoning. At the end of the thesis there is a maximum amount of methanol content in individual spirits and there is also a citation of the Act on alcohol, which stipulates the requirements for the production of alcoholic beverages. The final point is the methanol affair describing the course of the entire tragic event that happened in 2012.
|
|
|
DESIGN OF FIBER-OPTIC BIOSENSOR WITH NEAR-INFRARED SPECTRAL ANALYSIS
Křepelka, Pavel ; Jakubec,, Martin (referee) ; Skládal, Petr (referee) ; Mikulka, Jan (advisor)
This thesis deals with a measurement and interpretation of NIR spectra of bacterial cells and design of biosensor using this analytical technique. In the first chapter, there is introduction of current state of knowledge in the field of NIR spectroscopy in microbiology and technology of fiber optic biosensors. The summary of this chapter shows that NIR is a suitable technique for direct molecular analysis of bacteria, but it suffers from low sensitivity and insufficient interpretation of bacterial spectra. In the next part of the thesis, there is a theoretical background of spectral analysis techniques and technology of fiber optic sensors. In the practical part of this work, there is suggested the elimination of disadvantages of NIR spectroscopy in microbiology by a series of experiments used for interpretation of NIR spectra of bacteria and design of fiber optic sensor to increase sensitivity of this technique. In this work, spectral regions important for the identification of bacterial strains were determined and partially interpreted and the sensor for bacterial analysis capable of classifying strains based on 105 captured cells was designed. Therefore, the objectives of this work were fulfilled.
|
|
|
Crystallization of microbial polyesters - methods and biological consequences
Liczka, Jan ; Kalina, Michal (referee) ; Sedláček, Petr (advisor)
The aim of this bachelor thesis was to test suitable methods for preparation of amorphous form of microbial polyesters and to perform model experiment to study a kinetics of crystallization of prepared polyesters. The theoretical part deals with PHA characteristics and various methods of isolating PHB granules from bacterial cells. In the experimental part, measuring techniques such as analytical centrifugation, dynamic light scattering (DLS) and Fourier transform infrared spectroscopy (FTIR) were tested to characterize the properties of PHB granules. Furthermore, an experiment was performed to isolate native PHB granules from Cupriavidus necator using lysozyme, deoxyribonuclease and cell disruption by ultrasonification. The results of the analyzes showed that the granules were either isolated amorphous only in the wet and crystallized upon drying, or that the granules were completely amorphous but not isolated from the bacterial cell.
|
|
|
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.
|
|
|
Application of modern analytical methods for the study of selected boron coordination compounds
Hrušková, Helena ; Jelínek, Ivan (advisor) ; Dian, Juraj (referee)
This thesis is focused on the study of boron coordination compounds, specifically boron pyrogallol and 2,3-dihydroxynaphthalene ligand complexes. In the introductory part of the work are discussed the properties of boron compounds, their preparation, the possibility of separation by capillary electrophoresis and methods of structural characterization. In the first part of the thesis, the methods of preparation of complexes are discussed and for each complex the optimal yield response is chosen. The resulting products were studied by low resolution mass spectrometry. In the second part of the thesis, structures of complexes, including their modeling in the Gaussian program, were described more precisely. Furthermore, the complexes were characterized by high resolution mass spectrometry. The complexes were also studied by 11 B, 1 H and 1 H COSY NMR and IR spectroscopy. The third part was devoted to the separation of these substances from the mixture after the reaction. CE-UV and CE-MS techniques were used for this purpose. To convert the results, the separation method was developed in ammonium formate buffers that are compatible with both instruments. The equilibration between complexes and ligands was also monitored by CE-UV. A special chapter is the study of pyrogallol autooxidation by UV-VIS and...
|
|
|
Preparation and characterization of silicon-based materials
Šlechta, Miroslav ; Dian, Juraj (advisor) ; Jelínek, Ivan (referee)
Title: Preparation and characterization of silicon-based materials Author: Miroslav Šlechta Department: Department of Chemical Physics and Optics Supervisor: doc. RNDr. Juraj Dian, Csc., Department of Chemical Physics and Optics Abstract: Porous silicon is nanostructured material based on silicon. He was prepared by anodic etching of crystalline silicon in hydrofluoric acid. Physical and chemical properties of porous silicon nanocrystals resulting from the dimensions, which range from units to tens of nanometers. For nanostructured silicon compared to crystalline silicon, exhibit unique properties that depend on the degree of quantum dimensional phenomena and phenomena on its large internal surface. Suitable choice of the silicon substrate, particularly in terms of conductivity and crystallographic orientation, and technological conditions (in particular electrolyte composition, the etching time and current density) can be prepared nanostructured materials of different pore sizes - macroporous, mesoporous and microporous silicon and varying representation Si-O and Si-H bonds. Morphology and chemical composition of the surface of porous silicon allows to think of it as a suitable material for a range of applications - particularly chemical sensors and biosensors, optoelectronics and biomedical applications....
|
|
|
Characterization of proteins of 2'-5' oligoadenylate pathway by means of vibrational spectroscopy
Víšová, Ivana ; Kopecký, Vladimír (advisor) ; Bednárová, Lucie (referee)
The work concerns to structural characterization of two important proteins of 2'-5' oligoadenylate pathway participating in an immune response of organism to a viral infection. Studied proteins were ankyrin domain of mouse RNase L, the C-terminal part of human phosphodiesterase 12 and the complete human phosphodiesterase 12. The proteins were characterized by Raman spectroscopy, infrared spectroscopy, electronic circular dichroism, dynamic light scattering and in addition by two non-spectroscopic methods- differential calorimetry and electrophoresis. For each protein the secondary structures, thermal stability, weight of oligomers and generally a basic characterization by above mentioned methods were provided.
|
|
|
The influence of the quality of articulation UHMWPE inserts on the lifetime of joint replacements
Fulín, Petr ; Pokorný, David (advisor) ; Koudela, Karel (referee) ; Gallo, Jiří (referee)
This thesis focuses on the introduction with the problems of high molecular weight polyethylene (UHMWPE) in orthopedics in the first part. It discusses the history, properties and processes that lead to the failure of UHMWPE joint replacement components. The experimental part validates the hypotheses expressed. It acquaints readers with the experimental verification of the effect of different types of sterilization on the oxidative stability of laboratory prepared samples and explanted UHMWPE joint replacement components using methods of infrared microscopy, electron spin resonance, mechanical tests and tests of microhardness. Other experimental measurements on a large set of explanted components of hip and knee total joint replacements validates the hypothesis that the amount of oxidative damage affects the lifespan of joint replacements. The third part of the experimental study maps the degree of oxidative damage in different places of the hip and knee joint replacements. In the final part we experimentally demonstrate the fact that the rate of oxidative damage has an effect on supramolecular structure of the UHMWPE. From the above experiments are concluded clearly defined recommendations for clinical practice, which should lead to extend the lifespan of total joints replacements in orthopaedics....
|
guest ::
