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Characterization of separation systems for determination of enantiomers
Geryk, Radim
(EN) The dissertation thesis is focused on the research and characterization of retention and enantiorecognition mechanisms of chiral stationary phases based on derivatized polysaccharides. The separation systems with a variety of modern stationary phases (both achiral and chiral) were characterized in detail to provide a comprehensive view of the interactions participating in the separation process. The study of the retention/separation behavior significantly facilitates the development and the optimization of new enantioselective methods for a wide variety of compounds. The work deals with the comparison of enantioselective performance of polysaccharide-based chiral stationary phases. The objectives are to show the differences of separation behavior among these chiral stationary phases, as they differ by the nature of the polysaccharide backbone (amylose versus cellulose), by binding of chiral polymer to silica support (coated versus immobilized stationary phase) and by the phenyl moiety in the reversed and normal phase HPLC. In both separation modes amylose-based chiral stationary phases exhibited higher enantioselectivity, especially for acidic and bifunctional analytes. Chiral stationary phases based on derivatized cellulose showed higher enantiodiscrimination potential for basic analytes....
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Separation of hepcidin using magnetic sorbents with subsequent MALDI-TOF MS analysis
Vávrová, Jana ; Pacáková, Věra (advisor) ; Tichá, Marie (referee)
Hepcidin is cysteine-rich cationic peptide produced by hepatocytes, secreted into blood plasma, and excreted in urine. Hepcidin is proposed to be the key regulator of iron metabolism and an evaluation of changes in the hepcidin level is important for diagnosis of several diseases. However, methods used for the hepcidin detection and determination in urine and serum have certain limitations. At present time MALDI-TOF MS based approaches have been applied for final analysis of urinary and/or serum hepcidin levels. Before MS analysis, separation of hepcidin from analyzed samples is an important and necessary step. The aim of this study was to compare the ability of several magnetic sorbents with different coating matrix and/or different terminal functionalized groups to adsorb hepcidin prior MS analysis. Either commercial magnetic sorbents containing -COOH groups or magnetic hydrophilic IDA-modified polymethacrylate microparticles P(HEMA-co-GMA)-IDA with immobilized metal ions were use for this purpose. Hepcidin was adsorbed to magnetic sorbents containing linked carboxyl groups (i.e. to weak cation exchange magnetic particles) at pH 6.8 independently on a nature of magnetic particle coating layer. Magnetic particles P(HEMA-co- GMA)-IDA with immobilized Cu(II) ions were found to adsorb hepcidin in a...
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Portable and Miniaturized Separation Techniques Applicable for Food and Biotechnology Analysis
Dvořák, Miloš ; Pospíchal, Jan (referee) ; Bednář,, Petr (referee) ; Rittich, Bohuslav (advisor)
Capillary electrophoresis was used for determination of 6 fractions of caseins. Those fractions were measured in 144 samples of cow’s milk originated from the feeding experiment focused on explanation the influence of the feeding onto casein productions. In this work were separated 6 fraction of caseins first time with total resolution of the peaks. Capillary electrophoresis was applied for determination of short-chain organic acids during fermentation of wine must. It was compared the fermentation of must fermented by different yeast. The difference of profile short-chain organic acids during fermentation were not statistically significant. The once difference was in the utilisation of the malic acid and production of the lactic acid. A portable miniaturized system for medium pressure liquid chromatography was developed. The components were tested and system was used for the isocratic and gradient elution of various analytes (food dyes, parabens). New line of electroluminescent diodes (LEDs) for deep-UV areas of wavelength based on a different materials substrate was characterised. The new line was compared with old line LEDs. The new line LEDs was incorporated in deep-UV absorbance detectors. Detectors were characterised and tested for a detection various analytes in modes flow injection analysis and chromatography separation. First time was characterised this new line of the LEDs and the origin of the parasitic emission band produced by deep-UV LEDs light sources was explained. This origin is given by disturbances of a materials substrates. This work is a contribution for an advance of low-cost and portable systems and detection devices in the field of analytical chemistry.
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Magnetic separation
Balatý, Tomáš ; Brožek, Milan (advisor) ; Hrabě, Petr (referee)
The aim of the thesis was to gather information about magnetism, magnets and principles used in magnetic separation. The key point of this thesis was to assess the efficacy of an experimental magnetic separation operation. The first chapter is devoted to the introduction, which is a brief description of the problems of magnetic separation. The second chapter describes the current state of the problem, which explains the basic definitions and phenomena arising from the use of permanent magnets or electromagnets. Furthermore, this chapter describes in detail the magnetic separation. The third chapter is devoted to the work goals and methods of processing. The fourth chapter describes an experiment that was conducted to determine the effectiveness of a magnetic separator during the trial operation of transport technology to transport clinker. The last chapter is devoted to conclusions and contribution of this thesis.
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Improvement of Manganese Separation in Drinking Water Treatment
Bartoš, Ladislav ; Janda, Václav (referee) ; Hlaváč, Jaroslav (referee) ; Dolejš, Petr (advisor)
The submitted paper covers manganese comprehensively. The introduction provides an overview of its basic physical and chemical properties. Its compounds are discussed individually, including their preparation, production, and practical uses. Furthermore, a list of analytical methods in which manganese is involved in the form of its compounds as reagents is included. The same section includes an overview of analytical methods whereby manganese and its compounds are detected, primarily in water industry processes. Attention is paid to manganese as a non-negligible constituent of the various parts of the environment. The section on manganese’s biogenic properties is interesting from the viewpoint of its toxicity as well as its role as an important biogenic element, indispensable primarily for mammals. The subsequent chapters discuss the various methods which are suitable, under specific conditions, for separation in the treatment of surface and underground water aimed at producing drinking, process, or industrial water, where a minimal concentration of this metal is required. The impact of the physical/chemical conditions which influence the efficiency of separation in a manner ranging from non-negligible to principal, is discussed further on. Given the specifics of treatment of surface [and] underground water, the chapters provide more details on the processes suitable for specific types of matrix and specific conditions. Next chapters sum up many years of the author’s observations and experiences in the various parts of the water management system, from the raw water source to treatment to distribution, focusing on surface and underground water separately. Last chapter describes the construction of a water treatment plant model, its launch and calibration, and the tests focused on separating manganese by way of coagulation using aluminium and iron sulphate.
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Suspension flow modeling
Hideghéty, Attila ; Koutný, Luděk (referee) ; Rudolf, Pavel (advisor)
Diplomová práce se zabývá prouděním v hydrocyklónu. Hydrocyklón je separační stroj, kterým slouží k oddělování pevných částice z kapaliny (nejčastěji z vody). Díky tangenciálnímu vstupu do zařízení nastává silné vířivé proudění, které způsobuje přisávání vzduchu přes horní a dolní výtok. Toto vzduchové jádro hraje důležitou roli v separaci částic. Výpočty jsou provedeny pomoci CFD.
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Optimisation of a die casting part production.
Vencálek, Jaroslav ; Janský, Milan (referee) ; Píška, Miroslav (advisor)
The project aim is an optimalization of production of pressure die casting, which serves as a one part of handle in office furniture area. The main emphasis was for mass finishing operation, which serves for rounding of very sharp part edges after die casting operation. A few tests of single mass finishing parameter was carried out and as result was a few partial recommendations for an increasing of production efficiency and improving of manufacturing process, namely an adjustment of separation cycle, proposal of optimum amount of pieces in each single batch and an innovation of chips type and dimensions. The project includes a proposal of a new and more efficiency layout of pieces on the transport pallet.
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Aspects of airspace evaluation
Závodník, Ondřej ; Kujal, Tomáš (referee) ; Brhelová, Dana (advisor)
Diplomová práce se zabývá jednak popisem stavu letecké dopravy a to zejména co se týče její bezpečnosti, plynulosti, propustnosti a kapacity. Výše uvedené je poté zhodnoceno v části věnující se aspektům nebezpečnosti vzdušného prostoru v jednotlivých fázích letu.
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Human body detection in a video scene
Šmirg, Ondřej ; Číka, Petr (referee) ; Kohoutek, Michal (advisor)
The project consists of two distinct levels i.e. separation level and diagnostic level. At the separation level, statistical models of gaussians and color are separately used to classify each pixel as belonging to backgroung or foreground. Adopted method is mixture of gaussians.A mixture of gaussians model is suitable here because the results of the picture tests will not depend on the lens opening, but rather on the colors in the backgroung. A mixture of gaussians model for return data seems reasonable. The achieved results the used method on the real sequences are presented in the thesis. Diagnostic level is identified human body on the scene. Adopted method is ASM(Active Shape Models) with PCA(Principal Component Analysis). ASM are statistical models of the shape of human bodies which iteratively deform to fit to an example of the object in a new image.
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