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Sorption ability of humic acids
Pokorná, Markéta ; Havelcová, Martina (referee) ; Klučáková, Martina (advisor)
The Diploma thesis deals with humic acids and their ability to adsorb metal ions on their surface. Humic acids are aromatic polycyclic compounds which contain carboxylic and fenolic functional groups on their sidechains. Thanks to these functional groups humic acids can form complexes with metal ions of different stability and assist the partial immobilization of pollutants in the nature. In this thesis, the sorption of Pb2+ and Zn2+ ions on humic acids was studied by relatively new electroanalytic method called galvanostatic stripping chronopotentiometry. Experimental data were described by Freundlich and Langmuir isotherms. The results show that the amount of examined metal ions increases with their increasing concentration. Furthermore it was determined that Pb2+ ions are adsorbed better on humic acids than Zn2+ ions. Both metals are adsorbed better from solution containing only one metal ion than in presence of four metals at the same time (Cd, Cu, Zn and Pb) where the sorption of these metals is not influenced by the presence of other metals.
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Diffusion in humic gels with incorporated metal ions
Krpatová, Lenka ; Gregorová,, Eva (referee) ; Klučáková, Martina (advisor)
The main topic of this diploma thesis is the study of diffusion of humic gels with incorporation of copper ions. Humic gel was prepared by precipitation of humate sodium with 5 M copper dichloride. First, it was necessary to find a useful extraction of surfactant that would have extracted copper from humic gel. Magnesium chloride was chosen as optimal surfactant from obtain relation of concentration copper(II) ions on time. Magnesium chloride was used to elution of copper from the slices of the gel. In next part it was important to verify the diffusion method that reaction in gel was not proceed in. Elution from slices of the gel before and after diffusion were scaled on the UV/VIS spectrophotometer. Experiment was prepared for times 3, 12, 24, 48 and 72 hours. Coefficient of the diffusion was calculated from obtained results, but 72 hours was not counted to the result.¨ From the coeficient of diffusion theoretic concentration profiles were calculated and then they were compared with experimentally results. Profile for 72 hours shows that it was unusable because it was oblate and fringe and concentration was lower than in other profiles. Other theoretic profiles agree.
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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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Utilization of flow-through coulometry for study of reactivity of humic acids
Pavlíková, Marcela ; Sýkorová,, Ivana (referee) ; Klučáková, Martina (advisor)
Humic acids are part of humus material abounded in nature. Humic acids are generally aromatic stuffs with sidechains and there can be linked various functional groups as carboxylic and fenolic mainly. This functional groups are able to form transitions elements ions and complexes of different stability. This property can be used in the environment, because certain polutants should be imobilized in nature. Diploma thesis studies adsorption of metal ions Cu2+, Cd2+, Zn2+ and Pb2+ on humic acids by electroanalytical method called flow – through coulometry.
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Adsorption of metal ions on humic acids
Pokorná, Markéta ; Mgr. Martina Havelcová, Ph.D (referee) ; Klučáková, Martina (advisor)
The Bachelor´s thesis deals with humic acids and their ability to bind metal ions on their surface. Humic acids are generally aromatic polycyclic compounds, which contain phenolic and carboxylic functional groups on their sidechains. Because of their functional groups, they are able to form stable complex compounds. In this thesis, the adsorption of lead ions was studied by electroanalytical method called flow-through coulometry.
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influence of physical conditions on diffusion processes in humic gels
Marvan, Jan ; Pabst, Willi (referee) ; Klučáková, Martina (advisor)
Diploma thesis is based on diffusion processes of copper (II) ions to humic gels obtained from lignite. Solutions with various concentrations and acidity were exposed to diffusion for exact time 24 hours. After the diffusion was ended the copper (II) ionic concentration profiles of tubular gels were create and calculated total diffusion flux. The experiment showed that the higher acidity of copper (II) solution decrease an amount of immobilized Cu2+ ions to the humic gels. In comparison concentration/pH: concentration of the solution has higher influence on sorption metal ions than change of the pH.
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Interactions of pharmaceuticals with fulvic acids – calorimetric study
Papko, Nadezhda ; Sedláček, Petr (referee) ; Klučáková, Martina (advisor)
Tato diplomová práce se zaměřuje na studium interakcí mezi půdní organickou hmotou a vybranými léky pomocí izotermické titrační kalorimetrie. V rámci experimentu byly použity tři fulvinové kyseliny a léky: ibuprofen, diclofenac a sulfapyridine. Vybrané léky a fulvinové kyseliny byly rozpouštěné v roztocích NaCl a MgCl2, jelikož kovové ionty jsou přítomny v organickém materiálu půdy. Mobilita léčiv závisí na sorpci, což je interakce mezi léčivy a půdními částicemi. Faktory ovlivňující sorpční chování zahrnují vlastnosti léčiv, půdy a enviromentální podmínky. Během bakalářské práce podražilo optimalizovat metodu ITC pro daný studiu, což usnadnilo experimentální práce a zlepšilo vyhodnocení dat. Pomocí metody byli stanovené tepelné efekty (naměřené a porovnané) interakcí mezi fulvinovými kyselinami a léky.
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Determination of structure and dynamics of biomolecules by theoretical calculations of NMR spectroscopic parameters
Benda, Ladislav ; Sychrovský, Vladimír (advisor) ; Munzarová, Markéta (referee) ; Hrabal, Richard (referee)
iv Abstract Subject: Determination of structure and dynamics of biomolecules by theoretical calcu- lations of NMR spectroscopic parameters Author: Ladislav Benda, ladislav.benda@gmail.com Department/Institute: Institute of Organic Chemistry and Biochemistry, AS CR Supervisor: Dr. Vladim'ır Sychrovsk'y, Institute of Organic Chemistry and Biochemistry, AS CR, vladimir.sychrovsky@uochb.cas.cz Abstract: This doctoral work was focused on theoretical modeling of nuclear magnetic resonance (NMR) parameters in peptides and nucleic acids. Dependences of NMR para- meters on molecular structure and solvation were primarily modeled. Great emphasis was put on the comparison of the calculated data with the NMR experiment. The molecular models studied included the l-alanyl-l-alanine di-peptide (AA) and the phosphate group of nucleic acid backbone. Conformations of all three charged forms of AA in solution were determined and the respective pH-induced changes of experimental NMR chemical shifts and nuclear spin-spin coupling constants were explained. Dependences of NMR cross-correlated relaxation rates on the AA backbone geometry were calibrated. The 31 P NMR parameters in nucleic acid phosphate were systematically calculated in dependence on the backbone conformation and the phosphate solvation pattern. Qualitative rules...
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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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Determination of structure and dynamics of biomolecules by theoretical calculations of NMR spectroscopic parameters
Benda, Ladislav ; Sychrovský, Vladimír (advisor) ; Munzarová, Markéta (referee) ; Hrabal, Richard (referee)
iv Abstract Subject: Determination of structure and dynamics of biomolecules by theoretical calcu- lations of NMR spectroscopic parameters Author: Ladislav Benda, ladislav.benda@gmail.com Department/Institute: Institute of Organic Chemistry and Biochemistry, AS CR Supervisor: Dr. Vladim'ır Sychrovsk'y, Institute of Organic Chemistry and Biochemistry, AS CR, vladimir.sychrovsky@uochb.cas.cz Abstract: This doctoral work was focused on theoretical modeling of nuclear magnetic resonance (NMR) parameters in peptides and nucleic acids. Dependences of NMR para- meters on molecular structure and solvation were primarily modeled. Great emphasis was put on the comparison of the calculated data with the NMR experiment. The molecular models studied included the l-alanyl-l-alanine di-peptide (AA) and the phosphate group of nucleic acid backbone. Conformations of all three charged forms of AA in solution were determined and the respective pH-induced changes of experimental NMR chemical shifts and nuclear spin-spin coupling constants were explained. Dependences of NMR cross-correlated relaxation rates on the AA backbone geometry were calibrated. The 31 P NMR parameters in nucleic acid phosphate were systematically calculated in dependence on the backbone conformation and the phosphate solvation pattern. Qualitative rules...
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