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Use of thin layer chromatography for fractionation and characterization of organic matter isolated from alginite
Solanský, Pavel ; Sovová, Šárka (referee) ; Enev, Vojtěch (advisor)
This diploma thesis is focused on the study of structure and physicochemical properties of organic fractions of humic substances, which were obtained by the method of thin-layer chromatography. Humic substances, which were used in this study, were isolated from a sample of Slovak alginite based on the procedure of the International Humic Substances Society (IHSS). The following analytical techniques were selected for the characterization of isolated humic substances: thermogravimetric and elemental analysis, molecular absorption spectroscopy (UV/Vis), Fourier transform infrared spectroscopy (FTIR) and steady-state fluorescence spectroscopy. Each organic fraction of humic substances were characterized by molecular absorption spectroscopy (UV/Vis) and steady-state fluorescence spectroscopy. Using steady-state fluorescence spectroscopy, humic substances were found to be composed of fluorophores of humic and non-humic (protein) character. Organic fractions corresponding to the humic fluorophores were characterized by a higher content of oxygen substituents on the aromatic nukleus, a higher degree of aromaticity and also a higher molecular weight. The aim of this diploma thesis was to design and optimize the process of organic matter fractionation for the purpose of detailed understanding of the structure and properties of humic substances, which were isolated from the sedimentary rock alginite. Based on this, the practical applicability of the thin layer chromatography method to significantly reduce the molecular heterogenity of the studied humic substances was evaluated.
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Comparison of the fruits of some honeysuckle varieties in terms of content selected biologically active compounds
Veselý, Ondřej ; Diviš, Pavel (referee) ; Vespalcová, Milena (advisor)
This thesis is focused to the analysis of selected varieties of honeysuckle kamtschatica (Lonicera caerula var kamtschatica) and their comparison in terms of the content of biologically active substances. There were analysed only varieties grown in 2014. Theoretical part elaborates and characterized various parameters of biologically active compounds such as phenolic, anthocyanins and ascorbic acid and possibilities of their determination. Further it briefly surveys Kamchatka honeysuckle, its taxonomic and morphological properties and its nutritional properties. The experimental part of the work was focused on the description of the methods used for the analysis of biologically active substances and their analysis. Polyphenolic compounds and anthocyanin’s were determined spectrophotometrically and vitamin C was determined by high-performance liquid chromatography. The results and varieties were compared with each other. Overall, we can say that the variety with the highest content of all three analysed biologically active substances is a variety Valchová, which had the second highest content of polyphenolic compounds (546.3 mg · 100 g-1 fruits), the third highest contend of ascorbic acid (35.1 mg · 100 g-1 fruits) and the sixth highest content of anthocyanin (170.8 mg · 100 g-1 fruits)
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Physicochemical and structural analysis for characterization of native and modified humic acids
Solanský, Pavel ; Sovová, Šárka (referee) ; Enev, Vojtěch (advisor)
This bachelor thesis is focused on structural and physicochemical characterization of native and methylated humic acid. These samples of humic acids, which were isolated from oxidized brown coal Leonardite, were characterized by thermal and spectrometric methods. The following analytical techniques were selected to determine the structural and physico-chemical changes between native and methylated humic acid: thermogravimetry (TGA), elemental analysis (EA), molecular absorption spectroscopy (UV/Vis), Fourier transform infrared spectroscopy (FTIR), fluorescence spectroscopy and last but not least nuclear magnetic resonance (13C NMR). The aim of this bachelor thesis was to find the differences in the structure of selected humic acids and also to verify the suitability of the techniques, which were used to characterize these biocolloid substances.
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Study of gas influence on nanoparticle generation by electrical discharge in liquids
Simić, Sanja ; Horák, Jakub (referee) ; Kozáková, Zdenka (advisor)
The work is focused on the preparation and characterization of Ag nanoparticles generated by plasma of the electric discharge in liquids. In more detail, it examines the DC discharge and the formation of hydroxyl and hydrogen radicals. The process is chemical in situ reduction, which is one of the most important methods of producing Ag nanoparticles because it is simple and economical and can perform better dimension size control by optimizing experimental parameters. During experiments, changes were made in various parameters such as concentration, conductivity, solution pH, intensity and polarity of the applied voltage. Different parameters such as particle size, shape, specific surface, crystallinity and many others can affect the properties of the nanoparticles. In view of these facts, detailed analysis of both plasma and nanoparticles generated for the control of nanoparticle synthesis and subsequent application is essential. In this work a plasma analysis was performed by optical emission spectroscopy (OES) and the characteristics of nanoparticles by UV-VIS spectroscopy and scanning electron microscopy (SEM). Silver nanoparticles are used in many industries such as the food, textile, construction and energy industries as well as in medicine, cosmetology and pharmacy. Thanks to their widespread use they represent the future of nanotechnology.
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Physicochemical characterization of soil humic substances isolated from modal brown soil
Churina, Iuliia ; Doskočil, Leoš (referee) ; Enev, Vojtěch (advisor)
This bachelor thesis deals with the physicochemical characterization of soil humic substances isolated from brown earth modal based on the international IHSS procedure. Humic substances are organic compounds occurring in soil and have a significant influence on soil processes and properties. The aim of this work is to obtain detailed information on the physical and chemical properties of humic substances such as mean molecular weight (Mr), spectral characteristics, elemental composition and thermal stability. Soil humic substances samples were characterized by thermal techniques such as thermogravimetric (TGA) and elemental analysis (EA). Different instrumental methods such as UV/Vis spectrometry, infrared spectrometry and fluorescence spectrometry were used to analyze the samples. The results of this work can contribute to a better understanding of soil processes and properties, which can lead to improved agricultural production and environmental protection.
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Use of thin layer chromatography for fractionation and characterization of organic matter isolated from alginite
Solanský, Pavel ; Sovová, Šárka (referee) ; Enev, Vojtěch (advisor)
This diploma thesis is focused on the study of structure and physicochemical properties of organic fractions of humic substances, which were obtained by the method of thin-layer chromatography. Humic substances, which were used in this study, were isolated from a sample of Slovak alginite based on the procedure of the International Humic Substances Society (IHSS). The following analytical techniques were selected for the characterization of isolated humic substances: thermogravimetric and elemental analysis, molecular absorption spectroscopy (UV/Vis), Fourier transform infrared spectroscopy (FTIR) and steady-state fluorescence spectroscopy. Each organic fraction of humic substances were characterized by molecular absorption spectroscopy (UV/Vis) and steady-state fluorescence spectroscopy. Using steady-state fluorescence spectroscopy, humic substances were found to be composed of fluorophores of humic and non-humic (protein) character. Organic fractions corresponding to the humic fluorophores were characterized by a higher content of oxygen substituents on the aromatic nukleus, a higher degree of aromaticity and also a higher molecular weight. The aim of this diploma thesis was to design and optimize the process of organic matter fractionation for the purpose of detailed understanding of the structure and properties of humic substances, which were isolated from the sedimentary rock alginite. Based on this, the practical applicability of the thin layer chromatography method to significantly reduce the molecular heterogenity of the studied humic substances was evaluated.
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Physicochemical and structural analysis for characterization of native and modified humic acids
Solanský, Pavel ; Sovová, Šárka (referee) ; Enev, Vojtěch (advisor)
This bachelor thesis is focused on structural and physicochemical characterization of native and methylated humic acid. These samples of humic acids, which were isolated from oxidized brown coal Leonardite, were characterized by thermal and spectrometric methods. The following analytical techniques were selected to determine the structural and physico-chemical changes between native and methylated humic acid: thermogravimetry (TGA), elemental analysis (EA), molecular absorption spectroscopy (UV/Vis), Fourier transform infrared spectroscopy (FTIR), fluorescence spectroscopy and last but not least nuclear magnetic resonance (13C NMR). The aim of this bachelor thesis was to find the differences in the structure of selected humic acids and also to verify the suitability of the techniques, which were used to characterize these biocolloid substances.
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Study of gas influence on nanoparticle generation by electrical discharge in liquids
Simić, Sanja ; Horák, Jakub (referee) ; Kozáková, Zdenka (advisor)
The work is focused on the preparation and characterization of Ag nanoparticles generated by plasma of the electric discharge in liquids. In more detail, it examines the DC discharge and the formation of hydroxyl and hydrogen radicals. The process is chemical in situ reduction, which is one of the most important methods of producing Ag nanoparticles because it is simple and economical and can perform better dimension size control by optimizing experimental parameters. During experiments, changes were made in various parameters such as concentration, conductivity, solution pH, intensity and polarity of the applied voltage. Different parameters such as particle size, shape, specific surface, crystallinity and many others can affect the properties of the nanoparticles. In view of these facts, detailed analysis of both plasma and nanoparticles generated for the control of nanoparticle synthesis and subsequent application is essential. In this work a plasma analysis was performed by optical emission spectroscopy (OES) and the characteristics of nanoparticles by UV-VIS spectroscopy and scanning electron microscopy (SEM). Silver nanoparticles are used in many industries such as the food, textile, construction and energy industries as well as in medicine, cosmetology and pharmacy. Thanks to their widespread use they represent the future of nanotechnology.
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Comparison of the fruits of some honeysuckle varieties in terms of content selected biologically active compounds
Veselý, Ondřej ; Diviš, Pavel (referee) ; Vespalcová, Milena (advisor)
This thesis is focused to the analysis of selected varieties of honeysuckle kamtschatica (Lonicera caerula var kamtschatica) and their comparison in terms of the content of biologically active substances. There were analysed only varieties grown in 2014. Theoretical part elaborates and characterized various parameters of biologically active compounds such as phenolic, anthocyanins and ascorbic acid and possibilities of their determination. Further it briefly surveys Kamchatka honeysuckle, its taxonomic and morphological properties and its nutritional properties. The experimental part of the work was focused on the description of the methods used for the analysis of biologically active substances and their analysis. Polyphenolic compounds and anthocyanin’s were determined spectrophotometrically and vitamin C was determined by high-performance liquid chromatography. The results and varieties were compared with each other. Overall, we can say that the variety with the highest content of all three analysed biologically active substances is a variety Valchová, which had the second highest content of polyphenolic compounds (546.3 mg · 100 g-1 fruits), the third highest contend of ascorbic acid (35.1 mg · 100 g-1 fruits) and the sixth highest content of anthocyanin (170.8 mg · 100 g-1 fruits)
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