No abstract

The effect of additives of P2O5 on the solubility of molybdenum in the amorphous part of glass and on the phase composition of the crystallized part of the highly alkaline glasses of the Li2O–(Na2O–K2O)–B2O3-SiO2 system was studied. The comparison of the phase composition of samples with or without phosphorus prior and after annealing allowed to determine the change of solubility of molybdenum in the amorphous part of the samples and to evaluate the thermal stability of the synthesized glass-ceramic materials. It was found, that for the compositions without phosphorus and the samples without lithium, when molybdenum is added at the synthesis stage, almost all of the molybdenum is included only in the crystalline molybdates. The study has shown an increase in the solubility of molybdenum only in the structure of lithium-containing glasses with phosphorus.

No abstract

Vibrational spectroscopy is used to show that the effect of adding titanium to K 2 O-B 2 O 3 -SiO 2 glasses differing by the ratio of the boron and alkali metal contents is different. This result reflects the change in the structural role of titanium in the glass and is important for evaluating the influence of titanium additions on the properties of alkali borosilicate glass in the process of improving the glassy matrix materials used for the immobilization of radwastes.The mechanical, thermal, and chemical stability of the matrix materials used for immobilizing radwastes can be increased by varying the chemical composition using components that play different roles in the glass structure. Titanium is one of the abundant components of oxide glasses and is capable of changing the coordination number from four to six and, depending on its coordination number, acting as a glass-forming or modifying cation in the glass network. The ratio of titanium with different coordination in the glass structure is determined by its chemical composition [1,2] and affects the physical-chemical properties of glasses [3].The aim of the present investigation was to study the effect of titanium additions on the structure of alkali borosilicate glasses acting as the base for glassy matrix materials used for radwaste immobilization. The influence of the composition of these glasses on the coordination of titanium ions and the particularities of the anionic structure of the glass as a whole was studied for the example of titanium-containing borosilicate glasses in the potassium system. METHODS OF STUDYTwo series of potassium borosilicate glasses with and without titanium were synthesized for these investigations.

No abstract