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Calorimetric study of interactions of humic substances with metal ions
Solná, Irena ; Pospíšilová, Ľubica (referee) ; Klučáková, Martina (advisor)
The main object of the diploma thesis is study of interaction beetween humic acids and selected metal ions using calorimetric titration. The research about reactivity of humic substances is done comparing the different models used to describe the variety of properties of humic substances. In experimental part the methods of FT-IR spektrometry, potenciometric and conductometric titration are used to recieve the total acidity and carboxylic acidity of lignite humic acid. The optimalization of isothermic titration calorimetry is done to be used within study of reactivity of humic acids, revealing the best correlation with sols of studied humic acid. The basic organic compounds were used including benzoic acid, ftalic acid, salycilic acid, pyrocatechol and phenol as models of bonding groups in humic acids. The reaction enthalpy was calculated from the titration of models and results were compared with semiempiric quantum chemistry calculations following INDO method.
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Characterization of methylated humic acids
Solná, Irena ; Kislinger, Jiří (referee) ; Klučáková, Martina (advisor)
The main concern of this bachelor thesis was a characterization of the properties of methylated humic acids. Retrieval on modifications of acidic functional groups of humic substances was done. In addition appropriate experimental methods for assessing the impact of methylation of carboxylic groups of humic acids were selected. Methylation of formentioned carboxylic groups is used to improve stability of humic acids while working with them. The sample of methylated humic acids, produced by the University of Poitiers in France, was investigated by the following methods: UV-Vis spectroscopy, FT-IR spectroscopy, fluorescence spectroscopy and thermal analysis - TGA, DSC. The degree of methylation of carboxylic functional groups of methylated humic acids was considered using an indirect titration. Results were trade-off with the sample without methylation. The impact of gelation on properties of methylated and non-methylated humic acids was also studied.
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Humic substances as transport medium for plant nutrition
Vlková, Markéta ; Solná, Irena (referee) ; Klučáková, Martina (advisor)
This bachelor thesis treats about humic matters and their application in agriculture by means of hydrogels transport medium. It studies progressive releasing of substances, which could be used as more common nutrition for plants, prepared from superabsorbent polymers. Research was implemented in collaboration with industrial partners. The substances are synthetically made of sodium Lignohumate and mixture of industrial fertilizer called NPK. Released substances were characterized by using some methods. First, there were measured qualities, which didn’t specify released compounds, like swelling, conductivity, pH and absorption of hydrogels with different wavelengths. More details came with methods ICP-OES and ion chromatography. Hydrogels which contained both mixtures of matters written up, were studied in water solution for 5 weeks and every week all characterization were measured. From the results we can see that both of the mixtures decrease ability of hydrogel’s swelling, mainly NPK. Measuring of absorption showed that the most of the substances released from sodium Lignohumate were from hydrogels without NPK. By other measuring, we noticed realizing of potassium and phosphorus elements. The most of them were from hydrogels containing NPK. By measuring ion chromatography, we found chloride, phosphoric, sulfuric and nitric ions in solution.
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Study of reactivity and mobility of Cu(II) ions in humic hydrogels
Hegr, Martin ; Solná, Irena (referee) ; Klučáková, Martina (advisor)
This bachalor´s thesis is focused on the study of diffusion of cupric ions in gel of humic acid. The objective of this thesis was to investigate the effect of the concentration of cupric ions supply source duration of diffusion on transport through the gel. Cupric ions was used like the diffusion medium. Cupric ions are thanks their high affinty for the humic acids ideal on the diffusion through the humic gel. Three different concentration of CuCl2 were compared, specifically 0,05M, 0,1M and 1M, and also three different times, specifically 10 hours, 1 day and 3 days. To compare them was used method of diffusion couple. The data necessary for calculation were obtained by UVVIS spectrophotometry.
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Humic substances as transport medium for plant nutrition
Vlková, Markéta ; Solná, Irena (referee) ; Klučáková, Martina (advisor)
This bachelor thesis treats about humic matters and their application in agriculture by means of hydrogels transport medium. It studies progressive releasing of substances, which could be used as more common nutrition for plants, prepared from superabsorbent polymers. Research was implemented in collaboration with industrial partners. The substances are synthetically made of sodium Lignohumate and mixture of industrial fertilizer called NPK. Released substances were characterized by using some methods. First, there were measured qualities, which didn’t specify released compounds, like swelling, conductivity, pH and absorption of hydrogels with different wavelengths. More details came with methods ICP-OES and ion chromatography. Hydrogels which contained both mixtures of matters written up, were studied in water solution for 5 weeks and every week all characterization were measured. From the results we can see that both of the mixtures decrease ability of hydrogel’s swelling, mainly NPK. Measuring of absorption showed that the most of the substances released from sodium Lignohumate were from hydrogels without NPK. By other measuring, we noticed realizing of potassium and phosphorus elements. The most of them were from hydrogels containing NPK. By measuring ion chromatography, we found chloride, phosphoric, sulfuric and nitric ions in solution.
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|
|
Calorimetric study of interactions of humic substances with metal ions
Solná, Irena ; Pospíšilová, Ľubica (referee) ; Klučáková, Martina (advisor)
The main object of the diploma thesis is study of interaction beetween humic acids and selected metal ions using calorimetric titration. The research about reactivity of humic substances is done comparing the different models used to describe the variety of properties of humic substances. In experimental part the methods of FT-IR spektrometry, potenciometric and conductometric titration are used to recieve the total acidity and carboxylic acidity of lignite humic acid. The optimalization of isothermic titration calorimetry is done to be used within study of reactivity of humic acids, revealing the best correlation with sols of studied humic acid. The basic organic compounds were used including benzoic acid, ftalic acid, salycilic acid, pyrocatechol and phenol as models of bonding groups in humic acids. The reaction enthalpy was calculated from the titration of models and results were compared with semiempiric quantum chemistry calculations following INDO method.
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Study of reactivity and mobility of Cu(II) ions in humic hydrogels
Hegr, Martin ; Solná, Irena (referee) ; Klučáková, Martina (advisor)
This bachalor´s thesis is focused on the study of diffusion of cupric ions in gel of humic acid. The objective of this thesis was to investigate the effect of the concentration of cupric ions supply source duration of diffusion on transport through the gel. Cupric ions was used like the diffusion medium. Cupric ions are thanks their high affinty for the humic acids ideal on the diffusion through the humic gel. Three different concentration of CuCl2 were compared, specifically 0,05M, 0,1M and 1M, and also three different times, specifically 10 hours, 1 day and 3 days. To compare them was used method of diffusion couple. The data necessary for calculation were obtained by UVVIS spectrophotometry.
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Characterization of methylated humic acids
Solná, Irena ; Kislinger, Jiří (referee) ; Klučáková, Martina (advisor)
The main concern of this bachelor thesis was a characterization of the properties of methylated humic acids. Retrieval on modifications of acidic functional groups of humic substances was done. In addition appropriate experimental methods for assessing the impact of methylation of carboxylic groups of humic acids were selected. Methylation of formentioned carboxylic groups is used to improve stability of humic acids while working with them. The sample of methylated humic acids, produced by the University of Poitiers in France, was investigated by the following methods: UV-Vis spectroscopy, FT-IR spectroscopy, fluorescence spectroscopy and thermal analysis - TGA, DSC. The degree of methylation of carboxylic functional groups of methylated humic acids was considered using an indirect titration. Results were trade-off with the sample without methylation. The impact of gelation on properties of methylated and non-methylated humic acids was also studied.
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