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Study of optical properties of thin films of organic photovoltaic cells
Čuboň, Tomáš ; Schmiedová, Veronika (referee) ; Zmeškal, Oldřich (advisor)
This master´s thesis is focused on measurement of optical properties of thin layer of materials used in organic solar cells (OSC). The usage of graphene oxides and its reduced forms as parts of hole transport layer (HLT) in OSC were studied. At the beginning of the thesis, there is described basic theory necessary to understand the optical properties of thin layers. The thin layer deposition and reduction of GO are discussed too. The experimental part is aimed to the optical characterization of prepared thin films. The results from optical microscopy, UV-VIS spectroscopy, FT-IR spectroscopy and spectroscopic ellipsometry were obtained. At the end of the thesis, the results are concluded and compared with already published literature.
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Use of Hofmeister series of ions for fractionation of soil humic acids
Kebabová, Mona ; Doskočil, Leoš (referee) ; Enev, Vojtěch (advisor)
The bachelor thesis deals with the study of the structure and behaviour of humic acids (HA) in the presence of salts of the Hofmeister series of ions. Haplic Luvisol and sodium humate extracted from it were characterized by elemental analysis (EA) and thermogravimetric analysis (TGA) to determine the percentage of elements and ash. Fourier Transform Infrared Spectroscopy (FT-IR) was used to determine the functional groups in the sample. UV-VIS was used to investigate the effect of the Hofmeister salts. From its results were calculated the absorption coefficients EET/EBZ, E2/E3, E2/E4 and E2/E6, and the specific absorbance values SUVA254 and SUVA280. Other methods like Dynamic Light Scattering (DLS) and fluorescence spectroscopy were used to better understand HA's structure. The main goal of this bachelor thesis was to find a simple experimental method based on which we would be able to study supramolecular associations of HK, which are preferentially linked to the formation of weak intra- and intermolecular interactions in aqueous solutions.
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Use of Hofmeister series of ions for fractionation of soil humic acids
Kebabová, Mona ; Doskočil, Leoš (referee) ; Enev, Vojtěch (advisor)
The bachelor thesis deals with the study of the structure and behaviour of humic acids (HA) in the presence of salts of the Hofmeister series of ions. Haplic Luvisol and sodium humate extracted from it were characterized by elemental analysis (EA) and thermogravimetric analysis (TGA) to determine the percentage of elements and ash. Fourier Transform Infrared Spectroscopy (FT-IR) was used to determine the functional groups in the sample. UV-VIS was used to investigate the effect of the Hofmeister salts. From its results were calculated the absorption coefficients EET/EBZ, E2/E3, E2/E4 and E2/E6, and the specific absorbance values SUVA254 and SUVA280. Other methods like Dynamic Light Scattering (DLS) and fluorescence spectroscopy were used to better understand HA's structure. The main goal of this bachelor thesis was to find a simple experimental method based on which we would be able to study supramolecular associations of HK, which are preferentially linked to the formation of weak intra- and intermolecular interactions in aqueous solutions.
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Specificity of selected exocyst subunits in trichome development
Glanc, Matouš ; Žárský, Viktor (advisor) ; Binarová, Pavla (referee)
Trichomes are fine epidermal outgrowths covering aerial organs of most land plants. Although unicellular trichomes of Arabidopsis thaliana have long been used as a model system in plant cell and developmental biology, surprisingly little is known about the processes involved in cell wall biogenesis during the last stage of trichome maturation. A role of EXO70H4, a putative subunit of the vesicle tethering complex exocyst, in trichome maturation has recently been identified in our laboratory. Image analysis, histochemical detection and FT-IR spectroscopy methods were used in this study to analyze cell wall defects of the exo70H4 LOF mutant, revealing the mutation causes altered deposition of pectins and possibly also lignins and hemicelluloses. Transgenic lines with EXO70 paralogues driven by the EXO70H4 promoter were prepared and their analysis revealed that the closest paralogue EXO70H3, unlike EXO70A1 and EXO70B1, can complement the exo70H4 mutation. Based on the results, questions concerning trichome cell wall composition, the role of EXO70H4 in trichome maturation and functions of the plant exocyst complex are discussed. Keywords: Arabidopsis, trichome, cell wall, secretory pathway, exocyst complex, EXO70H4, FT-IR spectroscopy
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Secretory pathway in plant cell wall polysaccharide biosynthesis and FT-IR spectroscopy methods in plant cell wall composition analysis
Glanc, Matouš ; Žárský, Viktor (advisor) ; Votrubová, Olga (referee)
All plant cells are encapsulated in a cell wall that determines the cells' shape and size and is essential to many of their vital processes. The cell wall of streptophyte plants is composed mainly of polysaccharides of high molecular weight. Cellulose, the main constituent of the plant cell wall, is synthesized by protein complexes bound to the PM, while hemicelluloses and pectins are synthesized in the Golgi apparatus. Several proteins that participate in the synthesis of cell wall polysaccharides have been identified, but hundreds of them remain to be discovered. Secretory pathway plays an important role in plant cell wall biogenesis as it transports cellulose synthase complexes and noncellulosic polysaccharide molecules to the cell surface. Some regulatory mechanisms that might be involved in cell wall material secretion, such as actin cytoskeleton, Ca2+ gradient or PIP kinases have been proposed; however, the regulation of this process is very complex and far from being understood. FT-IR spectroscopy is a method that can detect molecular vibrations and provide information about chemical composition of virtually all substances. It has been used successfully in screens for cell wall mutants, the study of interactions between cell wall polymers, as well as other areas of cell wall biology. FT-IR...
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Specificity of selected exocyst subunits in trichome development
Glanc, Matouš ; Žárský, Viktor (advisor) ; Binarová, Pavla (referee)
Trichomes are fine epidermal outgrowths covering aerial organs of most land plants. Although unicellular trichomes of Arabidopsis thaliana have long been used as a model system in plant cell and developmental biology, surprisingly little is known about the processes involved in cell wall biogenesis during the last stage of trichome maturation. A role of EXO70H4, a putative subunit of the vesicle tethering complex exocyst, in trichome maturation has recently been identified in our laboratory. Image analysis, histochemical detection and FT-IR spectroscopy methods were used in this study to analyze cell wall defects of the exo70H4 LOF mutant, revealing the mutation causes altered deposition of pectins and possibly also lignins and hemicelluloses. Transgenic lines with EXO70 paralogues driven by the EXO70H4 promoter were prepared and their analysis revealed that the closest paralogue EXO70H3, unlike EXO70A1 and EXO70B1, can complement the exo70H4 mutation. Based on the results, questions concerning trichome cell wall composition, the role of EXO70H4 in trichome maturation and functions of the plant exocyst complex are discussed. Keywords: Arabidopsis, trichome, cell wall, secretory pathway, exocyst complex, EXO70H4, FT-IR spectroscopy
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Study of optical properties of thin films of organic photovoltaic cells
Čuboň, Tomáš ; Schmiedová, Veronika (referee) ; Zmeškal, Oldřich (advisor)
This master´s thesis is focused on measurement of optical properties of thin layer of materials used in organic solar cells (OSC). The usage of graphene oxides and its reduced forms as parts of hole transport layer (HLT) in OSC were studied. At the beginning of the thesis, there is described basic theory necessary to understand the optical properties of thin layers. The thin layer deposition and reduction of GO are discussed too. The experimental part is aimed to the optical characterization of prepared thin films. The results from optical microscopy, UV-VIS spectroscopy, FT-IR spectroscopy and spectroscopic ellipsometry were obtained. At the end of the thesis, the results are concluded and compared with already published literature.
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Secretory pathway in plant cell wall polysaccharide biosynthesis and FT-IR spectroscopy methods in plant cell wall composition analysis
Glanc, Matouš ; Žárský, Viktor (advisor) ; Votrubová, Olga (referee)
All plant cells are encapsulated in a cell wall that determines the cells' shape and size and is essential to many of their vital processes. The cell wall of streptophyte plants is composed mainly of polysaccharides of high molecular weight. Cellulose, the main constituent of the plant cell wall, is synthesized by protein complexes bound to the PM, while hemicelluloses and pectins are synthesized in the Golgi apparatus. Several proteins that participate in the synthesis of cell wall polysaccharides have been identified, but hundreds of them remain to be discovered. Secretory pathway plays an important role in plant cell wall biogenesis as it transports cellulose synthase complexes and noncellulosic polysaccharide molecules to the cell surface. Some regulatory mechanisms that might be involved in cell wall material secretion, such as actin cytoskeleton, Ca2+ gradient or PIP kinases have been proposed; however, the regulation of this process is very complex and far from being understood. FT-IR spectroscopy is a method that can detect molecular vibrations and provide information about chemical composition of virtually all substances. It has been used successfully in screens for cell wall mutants, the study of interactions between cell wall polymers, as well as other areas of cell wall biology. FT-IR...
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