Prediction of the properties of two-phase composites with a piezoactive component

The effective dielectric, piezoelectric, and elastic constants of two-phase macroscopically piezoactive 3-0 and 3-3 composites are calculated. It is assumed that one of the components is a polarized ferroelectric ceramic material and the other is an inactive material with variable elastic properties. The limiting case when the elastic compliances of the inactive material tend to infinity (porous ferroelectric ceramics) is considered. The adequacy of this model to production technologies of piezoelectric composites is discussed. Computational results are compared with experimental data.     

Equilibrium State of Inhomogeneous Plasma

We consider the problem of a self-consistent determination of an essentially inhomogeneous equilibrium state of classical plasma. The solutions of the stationary Vlasov–Poisson equations are constructed in the form of a localized transition layer that separates the domains of homogeneous plasmas with different equilibrium parameters. The layer can also transform into a local perturbation inside a homogeneous plasma. In both cases, the solution contains neither mass currents nor electric currents, and all electrodynamic and hydrodynamic quantities and their derivatives are continuous. The parameters of the adjacent domains uniquely determine the transition layer structure.     

Study of diffusion creep accompanying superplastic deformation of the alloy ZhS6KP

The development of diffusion creep (DC) accompanying superplastic deformation (SPD) of the highly doped nickel alloy ZhS6KP is studied based on an investigation of the redistribution of dispersed intragrain deposits of the phase of Ni₃(Al, Ti). Deposit-free zones (DFZ) are formed in the alloy, held at the temperature of SPD and accompanying deformation at the grain boundaries. The contribution of DC to the deformation was determined from a comparative analysis of the width of the DFZ in the deformed and undeformed parts of the samples for different grain sizes and rates of DC taking into account diffusion accommodation. It was established that for the optimum rate of SPD the upper limit of the contribution of DC to deformation for 2-m grains does not exceed 11%. It is concluded, based on the distribution of DFZ, that the effect of DC accompanying SPD is determined by diffusion fluxes, associated with the local concentration of stress accompanying the development of grain-boundary slipping.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 40–45, June, 1986.In conclusion, we thank Yu. M. Mishin for a useful discussion of the results.     

Oxygen chemisorption on divalent chromium ions in chromosilicate systems

A study has been made of the chemisorption of O₂ from various gaseous media on divalent chromium ions in chromosilicate systems under dynamic conditions. After passing through the chemisorbent layer the residual O₂ content of the gaseous mixtures is 10^–6–10^–7 vol. %. The adsorption capacity of the chemisorbents increases in proportion to their Cr(II) content and decreases as the moisture content increases in the gas mixture from which the oxygen is absorbed. The chemisorbents can be repeatedly regenerated by treating them with hydrogen.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 11, pp. 2500–2505, November, 1992.     

Conductivity of Composite Films Based on Conductive Polymer PEDOT:PSS,Graphene Oxide and Nanoparticles TiO2 for Contact Layers of Perovskite Photovoltaic Structures

Physics of the Solid State - The electrical properties of composite films based on conductive polymer PEDOT: PSS, graphene oxide (GO), and titanium dioxide nanoparticles (TiO2) (PEDOT: PSS–...     

J-Aggregates of Astaxanthin and Its Monoesters and Diesters

Moscow University Chemistry Bulletin - The conditions for the preparation of astaxanthin ester aggregates are optimized, and their physicochemical characteristics (size and absorption spectra) are...