Papers by Keyword: Silicate Melt

Abstract: Study and description of positive effect influence of Cr₂O₃ catalyst in controlled crystallization technology for production of stone casting silicate materials are provided. The introduction of heat treatment method that influences the forming of the structural components of produced material. The basis of manufacturing stone casting silicate materials is controlled crystallization of silicate melt that is organized in such a way that nucleation occurs within the melt and the final product has a fine grain structure. The structural components of silicate stone casting materials and their influence on strength properties are determined. The strength of stone casting silicate materials is the reduction in the difference in the temperature coefficients of linear expansion of crystal phases and residual glass phase.

Abstract: The paper considers the processes of plasma chemical synthesis of silicate melts produced from quartz-feldspar raw materials with a view to obtain new construction materials having the advanced functional performance. Results are presented which illustrate physicochemical research findings (X-ray diffraction analysis, infrared spectroscopy) related to quartz-feldspar raw materials and a melts produced there from.

Abstract: In the production of mineral fibers it is possible to synthesize high-temperature silicate melts from molybdenum ore tailings using low-temperature plasma. Physicochemical research was carried out in relation to raw materials and melt products.

Abstract: This article is devoted to research possibility of high-temperature silicate melts producing from feldspar wastes of molybdenum ores enrichment (Khakassia) with use of low-temperature plasma energy.

Abstract: This work aims to explore possible applications of the ab initio molecular dynamics (MD) in modeling of the soda-lime-silica (NCS) glass and melt doped with admixtures. Preparation of the basic glass (15.8 wt.% Na2O, 10.5 wt.% CaO, and 73.7 wt.% SiO2) by the MD simulation from scratch is described. The structure analysis of the NCS glass is presented in the form of total and partial radial distribution functions (RDF), coordination numbers, and fractions of Qn units. The reasonable first neighbor distances were obtained, even if a rather small basis set of electronic wavefunctions and softer pseudopotentials for atomic core regions were applied. All major discrepancies in the first neighbor distances can be easily explained, and the results can be improved if needed. The Qn distribution shows higher disproportionation of Q3 than NMR and Raman experimental data, however, it is lower than previous classical MD simulations.

Abstract: The specific features of the dynamics of oxygen ions in Ме2O · SiO2 (Ме = Li, Na, K, Cs) and Na2O·ZnO·P2O5 melts at а temperature of 2000 K were investigated bу the molecular dynamics method. It is demonstrated that, as in the systems studied earlier, the formation of defect complexes is а necessary condition fог an oxygen diffusion event to bе successful. The scenarios of generating defect соmplexes аrе described, and the lifetimes of these complexes are calculated. The structure of the defect complexes is determined. It is shown that two-membered rings, free and threefold-coordinated oxygen ions сап also bе involved in the formation of defect complexes.