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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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Mineral composition of agricultural soils developed on loess
Žigová, Anna ; Šťastný, Martin
The study is focused on the comparison of mineral composition of different soil types formed on loess. The soil types were classified according to the World reference base for soil resources. Samples were collected from individual soil horizons. Basic soil properties such as the particle-size distribution, pH values, CaCO3 contents, base saturation, cation exchange capacity, soil organic carbon and nitrogen were analysed using routine pedological methods. Mineral composition was evaluated on the basis of XRD analyses of the fraction < 0.001 mm. Semiquantitative mineral composition was calculated from the areas of basal peaks. The studied soils were found to be dominated by quartz, kaolinite and illite. Semiquantitative analyses of mineral composition of the Greyic Phaeozem, Haplic Chernozem and Haplic Luvisol revealed differences in the association and proportion of individual minerals.
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