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Study of humic and fullvic acids by excitation emission matrix method
Enev, Vojtěch ; Vala, Martin (referee) ; Fasurová, Naděžda (advisor)
A bachelor thesis was focused on fluorescence measurement by emission-excitation matrix method (EEM) and finding of the main fluorophores of soil humic and fulvic acids samples. The results of the position of the main peak of fulvic acid isolated from soil type Cambisol were compared and were similar to the position of Elliot soil FA standard II. For determining of secondary peaks of fulvic acids the synchronous method (3D SFS) at lower wavelengths was used.
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Application of thin layer chromatography (TLC) for fractionation of humic substances.
Hegrová, Nela ; Doskočil, Leoš (referee) ; Enev, Vojtěch (advisor)
The main aim of this Bachelor thesis was to suggest and optimize a method of fractionation of organic matter of humic substances using thin-layer chromatography (TLC). HS Pahokee Peat standards have been characterized by thermochemical and spectrometric techniques such as thermogravimetry, elemental analysis, UV-Vis and Fourier-transform infrared spectrometry. Molecular absorption spectrometry in the ultraviolet and visible range of electromagnetic radiation and steady-state fluorescence spectrometry were used for physicochemical characterization of organic fractions. Using fluorescence spectrometry, humic substances were found to be composed of fluorophores of humic and non-humic (protein) character. Organic fractions corresponding to the humic fluorphores were characterized by a higher aromaticity, average molecular weight and higher content of oxygen substituents on the aromatic nucleus. In contrast, the organic fractions corresponding to the protein constitutional units were distinguished by low values of the humification index. These tell us about microbial origin of these organic substances during the genesis of HS Pahokee Peat.
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Interaction of drugs with soil organic matter - calorimetric study
Papko, Nadezhda ; Sedláček, Petr (referee) ; Klučáková, Martina (advisor)
This bachelor thesis is focused on the study of the interaction of soil organic matter with selected drugs using isothermal titration calorimetry. Two fulvic acids and drugs were used in the experiment: ibuprofen, pyridine sulfate and diclofenac. The scope of the work was to test the method for studying the interactions between fulvic acids and drugs and to optimize it for specific humic substances and drugs. Isothermal titration calorimetry includes the possibility to determine very important thermodynamic parameters, which were determined during the measurement of the bachelor's thesis. The main goal was to measure and assess whether the interactions take place and what the thermal effects are.
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Influence of metal ions on microorganization of humic substances
Odehnalová, Nikola ; Krouská, Jitka (referee) ; Klučáková, Martina (advisor)
This bachelor thesis is focused on the study of influence of metal ions on microorganization of humic substances. This issue was studied on a sample od fulvic acid. Solution of cocentration 1 g/l was prepared from this sample. This solution was ten titrate with solutions of copper, calcium and magnesium ions. For this purpose, methods of dinamic and electrophoretic light scattering were used. The results obtained by these methods show that the solution of fulvic acid is the most made by associated molecules of fulvic acid. The size of molecules became larger and larger during titrations. Copper was sorpted the most.
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Physicochemical characterization of soil humic substances isolated from Fluvisol
Šátková, Eliška ; Kalina, Michal (referee) ; Enev, Vojtěch (advisor)
This bachelor thesis is focused on the physicochemical characterization of humic substances that are isolated from fluvisol. Humic substances were isolated by a standard procedure according to the International Humic Substances Society (IHSS). Extracted humic substances were further characterized by thermal and spectrometric methods, which include elemental (EA) and thermogravimetric analysis (TGA), UV/Vis, and FTIR spectrometry. Potentiometric titration was an important contribution to characterization. Based on the obtained data obtained from the EA and TGA, the content of biogenic elements and the thermal stability of HL were determined. Absorption coefficients were calculated from the measured UV/Vis spectra to determine the aromaticity and average molecular weight of HL. The HL functional groups were determined by FTIR spectra, and the acidity was determined by potentiometric titrations. The obtained results very well characterized the individual humic substances isolated from fluvisol.
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Isolation and fractionation methods for determination of humic substances content in Leonardite
Lišková, Kateřina ; Kalina, Michal (referee) ; Enev, Vojtěch (advisor)
The main aim of this thesis was to isolate humic substances (HA and FA) from the natural sample of Leonardite, to characterize their structure and physical and chemical properties. Among other things, the humic acid standard supplied by IHSS, isolated from Leonardite, originally from Dakota, USA, was also studied. The following thermal and spectrometric methods were used to characterize the samples of isolated humic substances: thermogravimetric analysis (TGA), elemental analysis (EA), ultraviolet-visible spectrometry (UV / Vis) and infrared spectrometry with Fourier transformation (FTIR). The atomic ratios were determined from the results of the elemental analysis. Absorption coefficients were calculated from the measured UV/Vis spectra and were used for the physicochemical characterization of these biocolloid compounds. The measured infrared spectra were used to identify the individual functional groups.
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Isolation of fulvic acids from soil origin and fluorescence study
Rubínková, Eva ; Kozáková, Zdenka (referee) ; Fasurová, Naděžda (advisor)
Aim of this bachelor thesis was to find the optimal procedure and evaluation of soil fulvic acid (FA) isolation (soil type Eutric Cambisol, locality Vatín). Soil Cambisol contained higher amount of fulvic acid than humic acid (37,5%). Isolation and purifying of fulvic acid was made with 0,3 % yield. Fluorescence measurement by synchronous mode was used and compared with spectra of FA standard Elliot II. SFS spectra were similar. The main fluorophore of FA sample at excitation 358 and emission 448 nm from SFS spectra was determined.
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Isolation and fractionation methods for determination of humic substances content in South Moravian lignite
Černý, Pavol ; Kalina, Michal (referee) ; Enev, Vojtěch (advisor)
This bachelor thesis focuses on isolation and fractionation of humic substances (HS) from the natural matrix of lignite, which comes from southern Moravia from the mine Mír Mikulčice. In the theoretical part, it informs the reader about the issue, starting with information about lignite and HS. In this work, the standard procedure of isolation and fractionation of HS was used as according to the International Humic Substances Society (IHSS). The content of HS in the natural matrix of lignite was determined, and then isolated HS were subjected to physicochemical characterization – elemental analysis (EA), thermogravimetric analysis (TGA), UV/Vis spectrometry, infrared spectrometry with Fourier transformation (FTIR) and the acidity of humic acids (HA) was determined by potentiometric titration. EA was used to detemine the content of biogenic elements, moisture and ash content were determined by TGA. By using FTIR, various functional groups and building blocks that are present in supramolecules of HS were indentified and absorption coefficients EET/EBT, E2/E4, E2/E3 a E4/E6 were determined by UV/Vis spectrometry. Results represent good characterization of HS isolated from lignite and are in agreement with scientific literature.
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The ifluence of inorganic nanoparticles on environmental compartments
Šram, Matěj ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
Nanoparticles are one of the newer risks for the environment. Their consumption is constantly rising and thus their entry into the environment is inevitably increasing. At the same time, nanopollutants are formed as by-products of anthropogenic activity. The theoretical part of the bachelor thesis describes the characteristics of nanoparticles and points out the possible risks in relation to the environment. In the experimental part, this work deals with the effect of platinum nanoparticles on dissolved organic matter. Platinum metals in the form of nanoparticles are significant anthropogenic pollutants, because they are released from automotive catalysts and are therefore the subject of this study.
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Dissociation behaviour of natural biocolloids
Karbanová, Kateřina ; Sedláček, Petr (referee) ; Klučáková, Martina (advisor)
This diploma thesis is focused on the study of dissociation behaviour of natural biocolloids, namely humic acids and fulvic acids. Humic and fulvic acids are natural, heterogeneous, high molecular weight substances which behave as weakly acidic polyelectrolytes and they have complex not exactly described structure. They are formed by biochemical transformations of organic residues (mainly plants). They are part of the soil, water, peat, sediments and coal. Solubility of humic acids is affected by pH value. The higher the pH value is the higher the solubility is. Fulvic acids are soluble in whole range of pH values. The aim of this diploma thesis is to determine the dissociation constant for the five kinds of humic acids and four kinds of fulvic acids, which have been isolated from various natural sources. These samples were purchased from IHSS. Dissociation constants were determined by the conductometric method and a combination of measurment pH and the content of acidic functional groups in Na2SO4. UV-VIS spectrophotometry method was used to characterize the quality of humic acids and fulvic acids.
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