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Relation between Preparation Parameters of Belite Cement and its Hydraulic Properties
Staněk, Theodor ; Palou, Martin (referee) ; Škvára, František (referee) ; Havlica, Jaromír (advisor)
The dissertation thesis is devoted to the study of belite clinkers and to the possibilities of the increase in their hydraulic activity. The mechanism and the kinetics of belite clinker formation were studied together with the relation of the velocity of these processes and the hydraulic activity of clinker. The influence of various parameters (degree of lime saturation, duration and temperature of burning) of the belite clinker preparation on the belite clinker development in time, on belite polymorphism, on the chemical composition of belite crystals and on the belite cement hydraulic activity was studied, too. The research methods used for the investigation involved electron microscopy, optical microscopy, X-ray diffraction analysis, high-temperature microphotometry and calorimetry. The resulting clinkers were hydraulically activated by addition of calcium sulfate. The experiments have proven that the higher rate of belite formation does not lead to the increase of its hydraulic activity, as opposed to that of alite. On the other hand, the chemical activation by sulfate anions enables to prepare clinker with relatively higher degree of lime saturation with minor admixture of alite and anhydrite, which is hydraulically activated. The work was concluded by experimental burning of belite clinker doped with sulfate anions in a model rotary kiln and by the preparation of cements blended with common industrial alite clinker. The results indicate the possibility of separate industrial production of special belite clinker alongside with common alite clinker and the production of economically and environmentally beneficial blended Portland cements with suitable technological parameters, or targeted production of special cements with properties corresponding to their required utilization.
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Ligand design for medicinal applications
Paúrová, Monika ; Kotek, Jan (advisor) ; Trávníček, Zdeněk (referee) ; Řezanka, Pavel (referee)
In recent years, copper radioisotopes have been extensively studied for their suitable coordination and physical properties. Nuclides 61 Cu, 64 Cu and 67 Cu are used in nuclear medicine - in diagnostic as well as in therapeutic applications. The aim of the Thesis is a study of the coordination properties of divalent copper as a stepping stone for the next potential applications. The presented Thesis consists of two thematic parts. The first part deals with the synthesis of cyclam derivatives. Sixteen new macrocyclic ligands with different phosphorus acid coordinating pendant arms (phosphinate, phosphonate, germinal P-C-P) were prepared; an analogous ligand endowed by carboxylic acid pendant arm as well as tetramethylcyclam without coordinating arm were prepared for comparison. The influence of the nature of coordinating acid pendant arms on selectivity and on the rate of copper(II) complexation was studied in detail. The protonation constants of the free ligands and the stability constants of the complexes with selected transition metal ions were determined by potentiometric titrations and by 1 H and 31 P NMR spectroscopy. Kinetic properties - i.e. studies of the formation rate and kinetic inertness of the copper(II) complexes - were performed by UV-Vis spectroscopy. The formation kinetics of the selected...
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Complexes of 1,4,7-triazacyclononane derivatives
Kubinec, Jan ; Kubíček, Vojtěch (advisor) ; Vojtíšek, Pavel (referee)
The aim of this thesis was to prepare monoamide of macrocycle H3NOTA, which was prepared by multiple step synthesis. Ligand was characterized by NMR, MS and X-ray difraction analysis. Acid-base properties were studied by potentiometric titrations. Four protonation constants pKa`s were found and these protonation constants are lower than pKa`s of H3NOTA. Coordination properties with selected metal ions from the first row of transition metal, metal ions of biological interest and with lithium ions were investigated by potentiometric titration. Stability constants show that monoethylamide derivative of macrocycle H3NOTA forms complexes with lower stability than diethylamide derivative of macrocycle H3NOTA. Stability constants for complexes which contains amide group are lower than for H3NOTA complexes. Kinetics of Ga3+ complexation was investigated at different pH by 71 Ga NMR. The rate constants of and half-lives of complexation were determined at pH = 1. The rate constant was higher and the half-life of complexation was shorter than for H3NOTA ligand. Key words: macrocyclic complexes, thermodynamic stability, formation kinetics, radiopharmaceutical
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Ligand design for medicinal applications
Paúrová, Monika ; Kotek, Jan (advisor) ; Trávníček, Zdeněk (referee) ; Řezanka, Pavel (referee)
In recent years, copper radioisotopes have been extensively studied for their suitable coordination and physical properties. Nuclides 61 Cu, 64 Cu and 67 Cu are used in nuclear medicine - in diagnostic as well as in therapeutic applications. The aim of the Thesis is a study of the coordination properties of divalent copper as a stepping stone for the next potential applications. The presented Thesis consists of two thematic parts. The first part deals with the synthesis of cyclam derivatives. Sixteen new macrocyclic ligands with different phosphorus acid coordinating pendant arms (phosphinate, phosphonate, germinal P-C-P) were prepared; an analogous ligand endowed by carboxylic acid pendant arm as well as tetramethylcyclam without coordinating arm were prepared for comparison. The influence of the nature of coordinating acid pendant arms on selectivity and on the rate of copper(II) complexation was studied in detail. The protonation constants of the free ligands and the stability constants of the complexes with selected transition metal ions were determined by potentiometric titrations and by 1 H and 31 P NMR spectroscopy. Kinetic properties - i.e. studies of the formation rate and kinetic inertness of the copper(II) complexes - were performed by UV-Vis spectroscopy. The formation kinetics of the selected...
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Synthesis and coordination properties of TACN phosphinate derivatives
Kohúteková, Soňa ; Kubíček, Vojtěch (advisor) ; Gyepes, Róbert (referee)
The aim of this work is preparation and characterization of a ligand for a selective complexation of gallium (III). The ligand is a derivative of macrocycle NOTA with bis(phosphinic) pendant arm. Protonation constants and stability constants with copper (II), nickel (II), zinc (II) and gallium (III) cations were determined by potentiometric titrations. The ligand was also used for studying complexation kinetics with gallium (III) ions and might serve as a potential contrast agent for 68 Ga-PET.
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Relation between Preparation Parameters of Belite Cement and its Hydraulic Properties
Staněk, Theodor ; Palou, Martin (referee) ; Škvára, František (referee) ; Havlica, Jaromír (advisor)
The dissertation thesis is devoted to the study of belite clinkers and to the possibilities of the increase in their hydraulic activity. The mechanism and the kinetics of belite clinker formation were studied together with the relation of the velocity of these processes and the hydraulic activity of clinker. The influence of various parameters (degree of lime saturation, duration and temperature of burning) of the belite clinker preparation on the belite clinker development in time, on belite polymorphism, on the chemical composition of belite crystals and on the belite cement hydraulic activity was studied, too. The research methods used for the investigation involved electron microscopy, optical microscopy, X-ray diffraction analysis, high-temperature microphotometry and calorimetry. The resulting clinkers were hydraulically activated by addition of calcium sulfate. The experiments have proven that the higher rate of belite formation does not lead to the increase of its hydraulic activity, as opposed to that of alite. On the other hand, the chemical activation by sulfate anions enables to prepare clinker with relatively higher degree of lime saturation with minor admixture of alite and anhydrite, which is hydraulically activated. The work was concluded by experimental burning of belite clinker doped with sulfate anions in a model rotary kiln and by the preparation of cements blended with common industrial alite clinker. The results indicate the possibility of separate industrial production of special belite clinker alongside with common alite clinker and the production of economically and environmentally beneficial blended Portland cements with suitable technological parameters, or targeted production of special cements with properties corresponding to their required utilization.
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