Electrical and galvanomagnetic properties of AuAl2+6%Cu intermetallic compounds at low temperatures

The AuAl2 intermetallic compounds are of substantial interest in view of their application potential. The investigated intermetallics AuAl 2+6%Cu were prepared from fine powders of AuAl2 and Cu by vacuum sputtering on a glass substrate and consisted of films with a thickness of about one micrometer. The films were annealed. The temperature and field dependence of the electroresistivity, the magnetoresistivity and the Hall effect of AuAl2+6%Cu films were measured in the temperature interval from 4.2 to 100 K and at magnetic fields of up to 15 T. We demonstrate that the temperature dependence of the electroresistivity has a minimum at T = 20 K and a metallic behavior above this temperature. The magnetoresistivity is very small (less then 1%), positive at low temperatures and negative above 12 K. The Hall coefficient is positive, which corresponds to the holes in a one zone model with a charge carrier concentration of about 1.6 1020 cm-3. © Published under licence by IOP Publishing Ltd

Spin-Orbit Interactions in Bilayer Exciton-Condensate Ferromagnets

Bilayer electron-hole systems with unequal electron and hole densities are expected to have exciton condensate ground states with spontaneous spin-polarization in both conduction and valence bands. In the absence of spin-orbit and electron-hole exchange interactions there is no coupling between the spin-orientations in the two quantum wells. In this article we show that Rashba spin-orbit interactions lead to unconventional magnetic anisotropies, whose strength we estimate, and to ordered states with unusual quasiparticle spectra.Comment: 36 pages, 12 figure

Civic patriotism among young sportsman in the South of Russia: Sociological analysis and diagnostics

Purpose: This article is aimed at revealing the specifics of civil and Patriotic practices in the youth environment of the South Russian region. Methodology: The sociological study used methods of qualitative operational analysis and theoretical interpretation of the obtained empirical data, as well as methods of sociological diagnostics aimed at the conceptual generalization of the results of empirical research by social recognition of the qualitative characteristics of civil patriotism in the youth environment as an integral social phenomenon. Result: In modern Russian society, patriotism is positively perceived by the majority, including young Russians, who associate it with love for the Motherland and a willingness to stand up for it. However, state patriotism in the youth environment lacks citizenship, that is, the desire of young people to actively participate in social Affairs, working for the benefit of society and the social environment. Applications: This research can be used for the universities, teachers and students. Novelty/Originality: The sociological analysis and diagnostics reveal the reasons for the low level of civic patriotism among young people, as well as the factors that hinder its development in regional communities in the South of Russia.The article was completed as part of the implementation of the State Assignment (Ministry of Education and Science of the Russian Federation), project No. 28.3486.2017 / PC “Civil patriotism in the formation and development of solidarity practices in the south of Russia: resource potential and conditions for its implementation”

Condensation of Silica Nanoparticles on a Phospholipid Membrane

The structure of the transient layer at the interface between air and the aqueous solution of silica nanoparticles with the size distribution of particles that has been determined from small-angle scattering has been studied by the X-ray reflectometry method. The reconstructed depth profile of the polarizability of the substance indicates the presence of a structure consisting of several layers of nanoparticles with the thickness that is more than twice as large as the thickness of the previously described structure. The adsorption of 1,2-distearoyl-sn-glycero-3-phosphocholine molecules at the hydrosol/air interface is accompanied by the condensation of anion silica nanoparticles at the interface. This phenomenon can be qualitatively explained by the formation of the positive surface potential due to the penetration and accumulation of Na+ cations in the phospholipid membrane.Comment: 7 pages, 5 figure

Lattice WW algebras and quantum groups

We represent Feigin's construction [22] of lattice W algebras and give some simple results: lattice Virasoro and $W_3$ algebras. For simplest case $g=sl(2)$ we introduce whole $U_q(sl(2))$ quantum group on this lattice. We find simplest two-dimensional module as well as exchange relations and define lattice Virasoro algebra as algebra of invariants of $U_q(sl(2))$. Another generalization is connected with lattice integrals of motion as the invariants of quantum affine group $U_q(\hat{n}_{+})$. We show that Volkov's scheme leads to the system of difference equations for the function from non-commutative variables.Comment: 13 pages, misprints have been correcte

Verification and Improvement of Flamelet Approach for Non-Premixed Flames

Studies in the mathematical modeling of the high-speed turbulent combustion has received renewal attention in the recent years. The review of fundamentals, approaches and extensive bibliography was presented by Bray, Libbi and Williams. In order to obtain accurate predictions for turbulent combustible flows, the effects of turbulent fluctuations on the chemical source terms should be taken into account. The averaging of chemical source terms requires to utilize probability density function (PDF) model. There are two main approaches which are dominant in high-speed combustion modeling now. In the first approach, PDF form is assumed based on intuitia of modelliers (see, for example, Spiegler et.al.; Girimaji; Baurle et.al.). The second way is much more elaborate and it is based on the solution of evolution equation for PDF. This approach was proposed by S.Pope for incompressible flames. Recently, it was modified for modeling of compressible flames in studies of Farschi; Hsu; Hsu, Raji, Norris; Eifer, Kollman. But its realization in CFD is extremely expensive in computations due to large multidimensionality of PDF evolution equation (Baurle, Hsu, Hassan)