V. A. Zhabrev

Ion Diffusion in Oxide Glasses and Melts: I. Bibliography

The first part of the review generalizes the basic results and the bibliography of experimental works on the self-diffusion and heterodiffusion of different-type ions in oxide glasses and glass-forming melts.

Interaction of Y2O3-Stabilized Cubic ZrO2 with Sodium Silicate and Sodium Aluminosilicate Glass-Forming Melts

The kinetics of interaction of the cubic solid solution 92ZrO2 · 8Y2O3 with sodium silicate and sodium aluminosilicate oxide glass-forming melts is investigated at a temperature of 1100°C. It is found that the stability of cubic γ-ZrO2 against dissolution in an oxide melt is determined by the composition of the anionic matrix of the melt and depends on the difference between the acid–base characteristics of oxide systems being in contact. It is demonstrated that this process can be described by the contracting volume equation and is limited by the rate of motion of the reaction interface.

Synthesis of BaTiO3 powders of different dispersities by the exchange reactions in molten salts

The possibility of synthesizing BaTiO3 ferroelectric powders of different dispersities by the exchange reactions in molten salts is demonstrated. The proposed method has some advantages, such as the possibility of preparing titanate materials of different dispersities and the simplicity and controllability of the chemical process.

Changes in the Energy Characteristics of the Surface of Organosilicate Coatings in the Course of Formation

The influence of the parameters of curing of organosilicate coatings and the degree of completeness of interfacial chemical reactions on the total surface energy, its dispersion and polar components, and the physicochemical and protective properties of coatings is analyzed. The possibility of using organosilicate coatings as easily cleanable materials is determined by the small values of the surface energy and its polar component.

Kinetics of formation of ZrB2-MoSi2 glass-ceramic heat-resistant coatings on graphite

Coatings on graphite with a high heat resistance at a temperature of 1400°C in an air atmosphere are prepared on the basis of the ZrB2-MoSi2-SiO2 system. It is demonstrated that the sealing vitreous layer is formed through oxidation of the composite components. The kinetic analysis of oxidation processes of the ZrB2-MoSi2 composite shows that the coating formation results from a set of concurrent and consecutive chemical reactions. The stages of forming the gas-impermeable layer are revealed, the schemes for oxidation reactions are proposed, and the kinetic parameters of reactions are determined.

Problems of nanotechnology in modern materials science

A review is presented of the current state of the art in the evolution of micro- and nanotechnology. The various methods of manufacturing nanosized elements are analyzed, and the prospects of applying individual nanoassembling methods as compared to possible batch methods for producing nanostructures are discussed. The principal directions of research in the field of group technologies are outlined, and their practical implementation is justified. The authors set forth their own standpoint of the problem and express willingness to debate it on any level.

The Influence of Chemical Composition of Silicate Glass-Forming Melts on the Kinetics of Their Interaction with Y2O3-Stabilized Cubic ZrO2

The influence of the chemical composition of sodium silicate, sodium calcium silicate, and sodium aluminosilicate glass-forming melts on the kinetics of their interaction with a 92ZrO2 · 8Y2O3 cubic solid solution is investigated. It is demonstrated that the kinetics and the mechanism of interaction are determined by the degree of dissociation of the anionic matrices of the melts under investigation. In turn, the degree of dissociation depends on the chemical nature and concentration of oxides (modifiers and network-formers) and the temperature. It is found that the process rate can be limited by the diffusion or chemical interaction depending on the reaction conditions.

Development of the Technology for Preparing and Storing Hydrogen with the Use of Nanostructured Materials for an Autonomous Integrated Wind Power Plant

This paper reports on the results of investigations into the design of an operating prototype of the power plant for the production and accumulation of hydrogen. The objective of this work is to develop technologies of intermediate storage of hydrogen with subsequent generation of an electric power due to the electrochemical processes occurring in fuel cells with an efficiency of no lower than 90%. The power plant is based on the wind power plant, which operates using an integrated software-hardware system for control over the power regime of the entire technological process. New membrane and catalytic materials prepared by the solgel method are used as functional components of fuel cells.

Investigation of the morphology of films based on sodium silicate by atomic-force microscopy

The characteristic features of the surface morphology of the films prepared by alkaline hydrolysis of silica are investigated using atomic-force microscopy. It is shown that the surface morphology of the films is influenced by the concentration of initial solutions and the modes of dehydration that are responsible for the processes of aggregation of nanoparticles, which affects the ratio between the amorphous and crystalline phases on the surface of the coating

Structural-mechanical properties of organosilicate composites with introduced curing agents

A systematic investigation on the rheological properties of five organosilicate suspensions of the “polyorganosiloxane-muscovite-talc-rutile-aminopropyltriethoxysilane-toluene” composition is undertaken. It is established that the sedimentation processes affect the energy characteristics of the surface of the organosilicate coatings prepared by curing the initial suspensions. The chemical processes occurring during long-term storage of the composites with introduced curing agents have an effect on the redistribution of the contributions from the polar and dispersion components to the total surface energy of the coating.