The glasses of various compositions in ternary system Li2O-P2O5-GeO2 and quaternary systems Li2O-B2O3-P2O5-TeO2, CaO-B2O3-P2O5-TeO2, Ag2O-B2O3-P2O5-TeO2, Li2O-B2O3-P2O5-GeO2 were synthesised and studied in 7 compositional series. The basic physicochemical properties of the glasses (density, molar volume, chemical durability etc.) were investigated using different analytical methods. The structure of glasses was studied using 31P, 11B MAS NMR and Raman spectroscopy. Thermal behaviour of glasses was investigated with the differential scanning calorimetry, thermodilatometry and hot-stage microscopy. From obtained thermoanalytical curves the values of glass transition temperature, dilatation softening temperature, crystallisation temperature and thermal expansion coefficient were obtained. DSC method was used also for the study of nucleation rate and nucleation (crystallisation) mechanism of the glasses. Crystalline phases obtained by annealing of glasses were identified by X-ray diffraction analysis.
Anotace v angličtině
The glasses of various compositions in ternary system Li2O-P2O5-GeO2 and quaternary systems Li2O-B2O3-P2O5-TeO2, CaO-B2O3-P2O5-TeO2, Ag2O-B2O3-P2O5-TeO2, Li2O-B2O3-P2O5-GeO2 were synthesised and studied in 7 compositional series. The basic physicochemical properties of the glasses (density, molar volume, chemical durability etc.) were investigated using different analytical methods. The structure of glasses was studied using 31P, 11B MAS NMR and Raman spectroscopy. Thermal behaviour of glasses was investigated with the differential scanning calorimetry, thermodilatometry and hot-stage microscopy. From obtained thermoanalytical curves the values of glass transition temperature, dilatation softening temperature, crystallisation temperature and thermal expansion coefficient were obtained. DSC method was used also for the study of nucleation rate and nucleation (crystallisation) mechanism of the glasses. Crystalline phases obtained by annealing of glasses were identified by X-ray diffraction analysis.
The glasses of various compositions in ternary system Li2O-P2O5-GeO2 and quaternary systems Li2O-B2O3-P2O5-TeO2, CaO-B2O3-P2O5-TeO2, Ag2O-B2O3-P2O5-TeO2, Li2O-B2O3-P2O5-GeO2 were synthesised and studied in 7 compositional series. The basic physicochemical properties of the glasses (density, molar volume, chemical durability etc.) were investigated using different analytical methods. The structure of glasses was studied using 31P, 11B MAS NMR and Raman spectroscopy. Thermal behaviour of glasses was investigated with the differential scanning calorimetry, thermodilatometry and hot-stage microscopy. From obtained thermoanalytical curves the values of glass transition temperature, dilatation softening temperature, crystallisation temperature and thermal expansion coefficient were obtained. DSC method was used also for the study of nucleation rate and nucleation (crystallisation) mechanism of the glasses. Crystalline phases obtained by annealing of glasses were identified by X-ray diffraction analysis.
Anotace v angličtině
The glasses of various compositions in ternary system Li2O-P2O5-GeO2 and quaternary systems Li2O-B2O3-P2O5-TeO2, CaO-B2O3-P2O5-TeO2, Ag2O-B2O3-P2O5-TeO2, Li2O-B2O3-P2O5-GeO2 were synthesised and studied in 7 compositional series. The basic physicochemical properties of the glasses (density, molar volume, chemical durability etc.) were investigated using different analytical methods. The structure of glasses was studied using 31P, 11B MAS NMR and Raman spectroscopy. Thermal behaviour of glasses was investigated with the differential scanning calorimetry, thermodilatometry and hot-stage microscopy. From obtained thermoanalytical curves the values of glass transition temperature, dilatation softening temperature, crystallisation temperature and thermal expansion coefficient were obtained. DSC method was used also for the study of nucleation rate and nucleation (crystallisation) mechanism of the glasses. Crystalline phases obtained by annealing of glasses were identified by X-ray diffraction analysis.
Zasedání zahájil předseda zkušební komise pro obhajobu disertační práce prof. Ing. Ladislav Koudelka, DrSc., který sdělil členům komise, že z jednání se omluvil ze zdravotních důvodů prof. Ing. Petr Lošťák, DrSc., takže jednání je přítomno 8 členů komise včetně tří jmenovaných oponentů. Dále pak představil členům komise Mgr. Marynu Vorokhtu ze studijního směru 2808V003 "Chemie a technologie anorganických materiálů", která předložila k obhajobě disertační práci s názvem: "Structure and properties of TeO2 and GeO2 containing phosphate and borophosphate glasses." a seznámil členy komise s doporučením školitele prof. Ing. Petra Mošnera, Dr. a stanoviskem vedoucího školicího pracoviště k předložené práci. Následně pak doktorandka seznámil komisi s předmětem a výsledky své disertační práce.
Po referátu doktorandky následovalo projednání oponentských posudků. Všichni tři oponenti postupně přečetli své posudky a následně doktorandka zodpověděla jejich dotazy a diskutovala jejich připomínky. V diskusi po projednání oponentských posudků byla pozornost zaměřena na výsledky termické analýzy a související stanovení teploty skelné transformace. Prof. Tichý upozornil na možnost fázové separace skel a jejího vlivu na průběh termoanalytických křivek. Prof. Gedeon zdůraznil nutnost chemické analýzy vzorků po syntéze a vlivy těkání některých komponent.
Po skončení veřejné rozpravy proběhlo neveřejné zasedání komise, na kterém došlo po debatě k hlasování. Z přítomných 8 členů komise se 8 vyjádřilo pro výsledek obhajoby "vyhověla" a udělení vědecké hodnosti doktor (Ph.D.) Mgr. Maryně Vorokhtě. Předseda komise poté seznámil doktorandku s výsledkem hlasování komise, poděkoval členům komise i oponentům za jejich účast na obhajobě a ukončil jednání komise.