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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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Voltammetric determination of homovanillic acid at boron doped diamond electrode for hollow fibre microextraction
Hrdlička, V. ; Barek, J. ; Navrátil, Tomáš
Presented work deals with hollow-fibre assisted liquid/liquid/liquid microextraction (HF-LPME) and subsequent voltammetric detection of clinical biomarker homovanillic acid (HVA). Three main areas are discussed: hollow fibre assisted extraction of HVA, voltammetric detection of HVA under basic conditions, and sensing in very small volumes. Using HF-PLME, HVA was extracted with 1-octanol as a supported liquid membrane with enrichment factor of 55 after 60 minutes of extraction. A novel method of miniaturized voltammetric determination of HVA using cathodically pretreated boron doped diamond electrode was also developed. Using differential pulse voltammetry, limit of detection, limit of quantificati was 1.9 mu mol dm(-3) on 6.6 mu mol dm(-3).
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Preparation of Magnesium Silicide from Recycled Materials for Energy Storage.
Bumba, Jakub ; Dytrych, Pavel ; Šolcová, Olga ; Koštejn, Martin ; Fajgar, Radek ; Maléterová, Ywetta ; Kaštánek, František
Recycling technologies help to save energy, materials and environment. This is the main reason of their popularity. The recovery of semiconductors and metals depends on recycling treatment. A new multi-step technology, which enables to obtain pure silicon and hydrogen from waste materials,is reported in this study. The only by-product is magnesium phosphate, which is a desired fertilizer. Magnesium silicide was successfully prepared from milled silicon photovoltaic (PV) panels and milled Mg obtained from the scrap. The formed magnesium silicide was then hydrolysed by phosphoric acid to form a mixture of silanes. Gaseous products (silanes) were separated by cooling below their boiling temperature by liquid nitrogen and then thermally decomposed by a hot wire, e.g. Pt.This treatment leads to pure silicon and hydrogen release. In this study a deep-in characterization by various methods spectroscopy, Scanning Electron Microscopy (SEM) with Energy Dispersive X- Ray spectroscopy (EDX), etc.) of prepared samples was also done to explain the individual influences, e.g. reaction temperature and atmosphere.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22016111814301 - PDF
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Enneagram-Development of Personality Type Test
Kilianová, Jana ; Bahbouh, Radvan (advisor) ; Niederlová, Markéta (referee)
The enneagram typology describes nine personality types and their mutual relations. It is a theoretical construct whose psychological validity is still being scientifically verified. The focus of this work is to develop a reliable and valid psychometric tool for recognizing the enneagram type and thereby verify the validity of this typology. The theoretical section describes the enneagram system on the basis of available literature and reviews research that set it in the psychological context. The empirical section deals with the development of the test to determine the ennea-type, with verification of its psychometric characteristics and criterion validity, and at the same time it examines the construct validity of enneagram typology. The criterion to review the validity is The Essential Enneagram Test by David Daniels, type identification by interview and self-identification. A quantitative data analysis was conducted on the sample of 300 persons of both, men and women of all ages using various kinds of statistical methods. The findings indicate that the tool developed to identify the ennea-type is reliable, of good psychometric quality and satisfactory criterion validity. Furthermore, the research supported the existence of nine enneagram types as per the theoretical construct, yet did not...
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Logistics management of inventory
Jankovská, Marie ; Štůsek, Jaromír (advisor) ; Ladislav , Ladislav (referee)
This diploma thesis deals with the issue of a logistic stock management in the company STOLFIG s.r.o. (Ltd.) that focuses mainly on the construction and production of metal products. The theoretical part deals with the basic terminology such as logistics, its management and targets. Nevertheless, most of the theoretical part is focused on the stock, specifically on its characteristics, structuring, management and also risks and costs connected with it.
At the beginning of the practical part, the company is introduced with the focus on the stock characteristics and its management system. The next part analyses the present stock management, particularly the analysis of costs, turnover and liquidity, and an ABC analysis. Attention is also paid to the signal level of the stock, the process of selecting suppliers, an unnecessary stock and a warehousing system. Every part is not only analysed but it is also evaluated whether the present situation is satisfactory or not.
The third part is based on the given analysis and it contains specific recommendations for improvement, namely in the field of the minimum stock determination, evaluation criteria for supplier selection, management with material with no turnover, and also recommendation for changes within the warehouse. The final part is a clear summary of the whole thesis.
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Quantification of Elements in Plant Materials by Electrothermal Vaporization Inductively Coupled Plasma Optical Emission Spectrometry
Šerá, Luisa ; Matějková, Stanislava ; Mestek, O.
This paper describes optimization and validation of operating conditions of electrothermal vaporization (ETV) inductively coupled plasma optical emission spectrometry (ICP-OES) method for quantification of Ba, Ca, Co, Cu, Fe, K, Mg, Mn, Na, P, Sr and Zn in plant materials. Besides the optimization of the temperature program, the selection of the gaseous modifier and the spectral wavelengths to be measured, it was studied how the sample quantity affects the result quality of the developed method. During the validation process, the accuracy and precision of the method were checked by analysis of a certified reference material. Limits of detection were estimated by analyses of blank samples. For almost all previously mentioned elements, the method meets requirements commonly applied on analyses by ETV combined with ICP-OES.
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Mass Spectrometry Imaging of Metformin in Tissue Sections
Strnad, Štěpán ; Sýkora, D. ; Vrkoslav, Vladimír ; Cvačka, Josef ; Maletínská, Lenka ; Pirník, Zdenko
Mass spectrometry imaging is a powerful technique suitable for visualization of the distribution of a wide variety of compounds within tissue sections. The main aim of the study was the development and optimization of a sample preparation procedure allowing determination of the distribution of orally dosed metformin in mice kidney sections. Metformin is the first-line medication for the treatment of type 2 diabetes. The optimization of the sample preparation step before imaging experiments included the selection of a suitable matrix and the optimization of various parameters of MALDI analysis. 2,5-dihydroxybenzoic acid was identified as the best matrix providing highest sensitivity. A sublimation method was successfully used for the matrix deposition. The highest relative concentration of metformin was found in the inner zone of kidney 30 minutes after the drug administration.
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Characterization of organic compounds in PM1 aerosol in Kladno in winter 2016
Křůmal, Kamil ; Mikuška, Pavel ; Večeřa, Zbyněk
In this work the organic compounds and organic markers used for the identification of main aerosol sources were measured in PM1 aerosol in a small town (Kladno-Švermov) near Prague. Monosaccharide anhydrides and resin acids (emissions from biomass combustion) were found especially. Polycyclic aromatic hydrocarbons (emissions from traffic and incomplete combustion), hopanes (traffic, coal combustion), steranes (traffic), saccharides and alkanes were other groups of analysed organic compounds.
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