The search for novel functional ceramic materials with targeted properties is currently very important. Complex oxides with perovskite or perovskite-related structure are being considered for the production of electrochemical devices for the hydrogen energy ecosystem. Layered perovskites including based on BaLaInO4 4 are promising materials for proton-conducting electrolyte of solid oxide fuel cells. The idea of this work is to create a triple conductivity material based on BaLaInO4. 4 . In this work, the doping of the lanthanum sublattice with iron ions was carried out for the first time. The effect of doping on the structure, water uptake and electrical conductivity was investigated. It was shown that the introduction of iron ions into lanthanum sublattice changes the crystal lattice from orthorhombic to tetragonal structure. The water uptake is very small and it is 0.02 mol H2O 2 O per formula unit for BaLa0.9Fe0.1InO4-delta 0.9 Fe 0.1 InO 4-delta composition. Studies of the electrical properties have shown that the nature of conductivity is mixed hole/oxygen ionic at dry air and hole/oxygen ionic/protonic and wet air. The Fe-doped- composition can be considered as triple conducting materials and it is prospective as the electrode materials comparable with protonic electrolyte Ba 1.1 La 0.9 InO 3.95 .

The influence of modifying nanopowders on the spreading and crystallization of a nickel droplet on a porous steel substrate is analyzed. For this purpose, a model has been developed for the spreading of a drop of liquid metal after its high-speed collision with a heated porous substrate. Due to the high impact velocity, the process of metal crystallization is considered after the complete spreading of the drop using the model of heterogeneous nucleation and macroscopic growth of the solid phase, taking into account the size and capillary effects. The influence of the impact velocity and substrate porosity on the thickness and diameter of the formed splat, the penetration depth, and the volume of liquid that penetrated the substrate has been studied. The numerical study of heterogeneous crystallization of a metal drop has made it possible to evaluate the influence of the modifying nanoparticle parameters, the impact velocity, and substrate porosity on the heterogeneous nucleation and on the resulting splat macrostructure.

A mathematical model of crystallization of a nanomodified metal drop after collision with a porous substrate is developed. The model takes into account the capillary and adhesive properties of the melt, as well as the processes of nucleation and growth of the solid phase during the cooling of the melt. Using numerical and analytical calculations, the influence of the physical parameters of the nanomodifier on the kinetics of nucleation, metal crystallization, and the formation of the crystal structure of the splat is analyzed. Numerical experiments were carried out for a nickel droplet modified with titanium nitride nanoparticles.

The mathematical model of the heterogeneous nucleation of a solid phase on a wetted spherical nanosubstrates is developed on the basis of the thermodynamic approach. According to the proposed model, new expressions for the nucleation energy and the nucleation rate of crystallization centers on spherical ultrafine seeds are obtained. The influence of size and capillary effects are taken into account. Numerical experiments were performed for an aluminum melt modified with silicon carbide nanoparticles. The results of calculations show that the wettability of the nanoparticle surface, as well as its size, has the greatest influence on the process of heterogeneous nucleation. Nanoseeds dispersion increase rises the nucleation rate of the solid, the wetting angle increase leads to an increase in the energy barrier, which impairs the nucleation process on large substrates to a bigger degree. The influence of size effects on heterogeneous nucleation on well-wetted spherical nanosubstrates (theta < 5(0)) can be neglected in the case of only large seeds R-p > 50 nm. This study is of interest for the development of a mathematical model of heterogeneous crystallization, describing the processes of structure formation in metals and alloys, modified by refractory nanoparticles.

The authors propose a model of heterogeneous nucleation and macroscopic growth of the solid phase on wettable refractory cubic nanoparticles. A numerical study of the crystallization process of a binary alloy with a phase diagram of the eutectic type modified by nanoparticles of titanium nitride are carried out. Within the proposed model, new expressions are obtained for the free energy and the nucleation rate of crystallization centers on cubic ultrafine seeds, taking into account the influence of size and capillary effects. The results of calculations reveal that the wettability of the substrate surface, as well as its size, has the greatest influence on the processes of nucleation and growth of crystals in a nano-modified melt. A comparison of the calculated parameters related to the issue under study with the experimental data shows satisfactory agreement.

A mathematical model of heterogeneous nucleation of a solid phase on highly activated wet-ted nanosubstrates of cubic form is proposed. This model is based on the classical thermodynamic approach. In accordance with the classical approach to describing the process of heterogeneous nucleation, it is assumed that critical nuclei have the shape of a spherical segment, and can be located on all six faces of a cubic seed particle. In the framework of the proposed model, we have obtained new expressions for the energy of formation and the rate of nucleation of crystallization centers on cubic nanoseeds which take into account the influence of size and capillary effects. Numerical experiments were carried out for an aluminum melt modified with nanoparticles of titanium nitride (TiN). The results of calculations show that the wettability of the surface of the nanoparticle has the greatest influence on the process of heterogeneous nucleation. An increase in the dispersion of nanosubstrates increases the nucleation rate of the solid phase. Taking into account the size dependence of the surface tension at the nucleus-melt interface significantly affects the nucleation processes only when the ratio of the Tolmen parameter to the critical radius is 2 δ / R 0 > 0.01. This study is of interest for the development of a mathematical model of heterogeneous crystallization describing the processes of structure formation in metals and alloys modified by refractory nanoparticles.

A mathematical model of the crystallization of a binary metal alloy inoculated with exogenous refractory nanoparticles has been developed. The process of cooling and solidification of an aluminum alloy with a phase diagram of the eutectic type is considered. Equations describing the growth of the solid phase with the continuous cooling of the alloy to the eutectic temperature and subsequent crystallization of the eutectic are given. Verification of the proposed model was carried out by comparing the results of numerical calculation of the crystallization process of the binary Al + Si system with the corresponding data of the physical experiment.

A mathematical model of the heterogeneous nucleation of a solid phase in a melt modified by exogenous refractory nanoparticles is developed. Analytical expressions are obtained for the free energy of formation and the rate of heterogeneous nucleation of the solid phase, taking into account the influence of dimensional and capillary effects. The study is of interest for constructing a mathematical model of heterogeneous crystallization that describes the processes of structure formation in metals and alloys modified by refractory nanoparticles.

Solidification of liquating silicate magmatic melts may lead to formation of rare earth mineral deposits. By the example of quasi-binary system SiO 2 –Sc 2 O 3 , the processes of cooling and directional solidification of the melt in an intrusive chamber have been studied, and velocities of the phase fronts and the width of the phase separation field have been calculated. Using the fluctuation approach, the physical and mathematical model of the formation and growth of dispersed phase in the continuous cooling of liquating melt was developed, and the conditions of incorporating the dispersed inclusions by solidified matrix phase were determined. The proposed model allows obtaining quantitative estimates of the size and number of inclusions per unit of hardened rock, depending on the solidification conditions and the initial chemical composition of the melt.

On the basis of thermodynamic approach, a mathematical model of nucleation and growth of the solid phase on highly activated wettable nanoseeds is proposed. New expressions for the free energy of formation and the rate of nucleation of crystallization centers on ultradispersed seeds (nanoparticles) obtained in the model take into account the influence of dimensional and capillary effects. Numerical experiments were carried out for Al+Si alloy modified with titanium nitride nanoparticles TiN. The results of the calculations were compared with the experimental data. The study is of interest for constructing a macroscopic model and understanding the mechanisms of structure formation in the case of heterogeneous crystallization of metals and alloys.

A quantitative analysis of sublimation of intensely fractured rocks in the mantle wedge was performed using a model of planar fracture channel. The use of dimensionless variables allowed us to analyze the influence of the Nusselt and Sherwood criteria on temperature and variation of the rates of dissolution of minerals and films on fracture walls and estimate both linear and mass sublimation rates. The results of this study predict relatively high rates of major element dissolution and remobilization by flows of magmatic and metamorphic gases over wide temperature range. Physical modeling of this process using natural mantle rock samples confirms the plausibility of the proposed model at least for the case of metamorphic-driven remobilization of elements from gas-liquid inclusions in metasomatized ultramafic rocks. This model provides a satisfactory explanation for the observed local heterophase alterations within ultramafic rocks that have experienced multistage deformation beneath volcanoes of the Kamchatka volcanic front.

It is shown the possibility of using superfine amorphous silicon dioxide SiO2onH2O of natural and technogenic origin for the synthesis of wollastonite. Natural silica is presented by diatomite selected at the Puzanov Cape (Kunashir Island, Kuril Islands). Amorphous silica of technogenic origin is obtained when complex processing of fluorineontaining waste at the Yaroslavsky Mining and Processing Plant. Wollastonite produced of these types of raw material can be used in various industries i.e. paint industry, production of building materials, pigments and sorbents for purification of aqueous media.

The origin of gold and silver deposits in the Southern Kamchatka ore district is considered in terms of a quantitative model of the dynamics of volcanogenic orthomagmatic fluid systems (VOFSs). This model takes into account structural, fluid dynamic, and thermophysical features of phase evolution in hydrothermal fluid systems differing in geometry and structural conditions of the discharge on the surfaces of volcanic edifices. It is shown that VOFSs forming sulfide-rich gold and silver deposits have no stationary impermeable caps in their discharge areas. Rather, for the most part, narrow regions of junction of phase fronts form in their interiors and migrate to the surface of volcanic edifices.Three geothermal system types are predicted by the example of plane and conical fluid conductance zones with a cap horizon: (I) where the shallow decompression boiling zone does not arise at all because of large lateral heat loss, (II) where subsurface decompression boiling zones appear at the beginning of the heat wave formation and then such a zone is practically confined to the cap rocks, and (III) where a quasistationary decompression boiling zone forms after an initial instability period or approach to a thermal equilibrium. Fluctuations or oscillations of decompression boiling zone fronts within a range of depths can exist in type III systems.. (C) 2012, V. S. Sobolev IGM, Siberian Branch of the RAS. Published by Elsevier B. V. All rights reserved.

The paper presents the results of numerical simulation of a subaerial volcanic hydrothermal system. The model is based on the factual data on the rock composition and the geological structure of the Mutnovsky Volcano. We develop a new approach to construct the numerical model of a volcanic hydrothermal system. According to this approach, at each step of the calculation, for each point of the spatiotemporal domain, the thermophysical properties are determined; further, these properties are used in the calculation of the equilibrium state of the system. This procedure allows us to take into account the dynamic changes in the T-P conditions in the cross section and the migration of the phase boundaries. As well, using this approach, we can pass from "conditional" time in the description of the evolution of the magmagenic fluid system to the "virtually dimensional time" of the development of the simulated ore-magmatic system, from the onset of melt crystallization in the intrusive chamber up to the termination of the retrograde boiling of the melt. The simulation shows that, depending on the structure of the lower part of the section, contrasting hydrothermal systems can develop in the originally homogeneous medium. The relation between the temperature, and, therefore, phase composition of the fluid and the features of the hydrothermal alteration in volcanic rocks is demonstrated. Among other questions, in the present paper we discuss the changes in the density and magnetic properties of the volcanogenic section.

В статье приведены результаты численного моделирования субаэральной вулкано-гидротермальной системы. В основу модели положены фактические данные по составу пород и строению разреза в. Мутновский. Для создания численной модели вулкано-гидротермальной системы нами разработан новый подход, при котором на каждом шаге расчета для любой точки в пространственно-временных координатах определяются теплофизические свойства, которые используются при расчете равновесного состояния системы. Это позволяет учитывать динамическое изменение ТР-условий в разрезе, миграцию фазовых границ и перейти от “условного” времени в характеристике эволюции магматогенной флюидной системе к “виртуально размерному времени” развития моделируемой рудно-магматической системы от момента начала кристаллизации расплава в интрузивной камере до прекращения ретроградного кипения расплава. Результаты моделирования показали, что в зависимости от строения нижней части разреза в первоначально однородной среде будут развиваться контрастные типы гидротермальных систем. Продемонстрирована зависимость между температурой и, как следствие, фазовым составом флюида и особенностями гидротермального преобразования вулканогенных пород. В данной статье, в частности, обсуждается особенности изменения плотности и магнитных свойств вулканогенного разреза.

The dynamics of phase fronts in a hydrothermal solution filtering through the fluid-conductor pores upwards to the earth surface was investigated on the basis of the model of volcanogenic orthomagmatic fluid systems. The problem was solved with regard for the rise and gradual extinction of the "source" of a fluid related to the crystallization of water-saturated basite magma in a shallow intrusion chamber. The influence of the porosity and permeability of supra-intrusion rocks as well as the heat-exchange conditions at their boundaries on the evolution of the orthomagmatic fluid system was investigated.