On the Static Dielectric Permittivity for Coulomb System in the Long Wavelength Limit

On the basis of the exact relations the general formula for the static dielectric permittivity for Coulomb system is found in the region of small wave vectors. The obtained formula describes the dielectric function of the Coulomb system in both limits: in the "metallic" state and in the "dielectric" one. On this basis the determinations of the "apparent" dielectric and the "apparent" radius of screening are introduced. In the random phase approximation (RPA) the exact relations for the function dielectric function of the electron gas in the long-wavelength region of the wave vectors are found for an arbitrary degeneration of the particles.Comment: 5 pages, no figure

Key tools for conducting an information audit of a higher education institution

This article focuses on the specifics of conducting a brand audit of a higher education institution (HEI) in a digital environment. The tools and peculiarities of information audit are considered and highlighted. The main advantages, differences and functionality of contemporary automatic media monitoring systems are analysed, with the focus on a number of specialised domestic and foreign closed access resources: Medialogy, Integrum, Public.ru, IQBuzz, Factiva, LexisNexis. The information on the main closed access systems is collected. Public relations and social media marketing performance evaluation indices are described. The analysis of secondary research on university reputation management is made, the results of which confirmed the hypothesis of the article about the importance of working with the media portrait of the university. It is concluded that it is necessary to conduct information audits of HEIs as part of their reputation management

Role of MNCs in changing preferences for food consumption in Russia under import substitution

The paper analyses the changes in the food market in terms of supply and demand in the context of import substitution and a decrease in the purchasing power of the population. It explores the reasons behind a rise in food prices, studies consumer preferences and criteria for choosing food products, and reveals the distinguishing features of Russian consumers’ behavior in the food market under the conditions of the import substitution policy. The article shows that, in general, multinational companies engaged in the food industry have managed to successfully integrate into the import substitution policy in the context of post-crisis development.peer-reviewe

Russian industry in global value-added chains

The paper analyzes Russia's participation in global value-added chains in the context of global trends in their development and the challenges facing the Russian economy in modernizing its industry. The analysis is based on the OECD’s TiVA indicators. The results indicate that the extent of Russia's involvement in GVACs is very significant, but the nature of this participation is purely raw. The specificity of the participation of the Russian Federation in the international fragmentation of production within GVACs is that most of the links in value chains are bottom-up. Russia is extremely limited in using imported flows to create export products with high added value. The study confirms that in the international division of labor, Russia retains a historically established specialization, with predominance in the export of mineral and agricultural raw materials, which determines the current profile of Russia's participation in global value-added chains.peer-reviewe

Heat transfer under high-power heating of liquids. 1. Experiment and inverse algorithm

A new approach to fluids behavior study in the course of highpower heating has been developed by us. The approach combines experimental method of controlled pulse heating of a wire probe and numerical method of thermophysical properties temperature dependencies recovery from the experimental data. Short (millisecond) characteristic time scale allows working with short-lived fluids, including superheated (with respect to the liquid-vapor equilibrium temperature and/or to the temperature of thermal decomposition onset) ones. Numerical method gives a set of inverse heat conduction problem solutions, based on the results of single pulse experiment. Numerical technique, based on the heat transfer parameters optimization model, is built using genetic algorithms. The approach was applied to saturated hydrocarbons in the temperature range 300-625 K. © 2013 Elsevier Ltd. All rights reserved

Numerical study of the normal current density behaviour in a narrow - gap glow discharge

A numerical study of normal glow discharge properties was performed in the case of small electrodes separations (0.05-0.4 cm) and moderate gas pressures (10-46 Torr). A recently observed new experimental effect of a considerable reduction in the normal current density for smaller discharge lengths was analyzed both by means of 2D fluid model and by a minimal 1D drift model of gas discharge. A good agreement between theoretical and experimental behaviour was demonstrated. An influence of the electrodes separation and of the gas heating on the value of the normal current density is discussed.Comment: 20 pages, 4 figure

Voltage-dependent behavior of a "ball-and-chain" gramicidin channel

This is the published version. Copyright 1997 by Elsevier.The channel-forming properties of two analogs of gramicidin, gramicidin-ethylenediamine (gram-EDA), and gramicidin-N,N-dimethylethylenediamine (gram-DMEDA) were studied in planar lipid bilayers, using protons as the permeant ion. These peptides have positively charged amino groups tethered to their C-terminal ends via a linker containing a carbamate group. Gram-DMEDA has two extra methyl groups attached to the terminal amino group, making it a bulkier derivative. The carbamate groups undergo thermal cis-trans isomerization on the 10–100-ms time scale. The conductance behavior of gram-EDA is found to be markedly voltage dependent, whereas the behavior of gram-DMEDA is not. In addition, voltage affects the cis-trans ratios of the carbamate groups of gram-EDA, but not those of gram-DMEDA. A model is proposed to account for these observations, in which voltage can promote the binding of the terminal amino group of gram-EDA to the pore in a "ball-and-chain" fashion. The bulkiness of the gram-DMEDA derivative prevents this binding