The three-dimensional randomly dilute Ising model: Monte Carlo results

We perform a high-statistics simulation of the three-dimensional randomly dilute Ising model on cubic lattices $L^3$ with $L\le 256$. We choose a particular value of the density, x=0.8, for which the leading scaling corrections are suppressed. We determine the critical exponents, obtaining $\nu = 0.683(3)$, $\eta = 0.035(2)$, $\beta = 0.3535(17)$, and $\alpha = -0.049(9)$, in agreement with previous numerical simulations. We also estimate numerically the fixed-point values of the four-point zero-momentum couplings that are used in field-theoretical fixed-dimension studies. Although these results somewhat differ from those obtained using perturbative field theory, the field-theoretical estimates of the critical exponents do not change significantly if the Monte Carlo result for the fixed point is used. Finally, we determine the six-point zero-momentum couplings, relevant for the small-magnetization expansion of the equation of state, and the invariant amplitude ratio $R^+_\xi$ that expresses the universality of the free-energy density per correlation volume. We find $R^+_\xi = 0.2885(15)$.Comment: 34 pages, 7 figs, few correction

Potential of export-oriented import substitution in the eurasian economic union: The case study of the agro-industrial complex

-Digitalization offers great opportunities for the development of economic potential. This is especially true for members of the Eurasian Economic Union (EEU) who face fierce competition in international markets from the developed countries. The purpose of this article is to substantiate the possibilities of the most complete use of the potential of export-oriented import substitution in the EEU in the agro-industrial sector under the conditions of digitalization of the economy. To achieve the goal of the study, the approach was used based on a combination of methods for the comprehensive analysis of the areas of strategic development of agro-industrial enterprises and statistical analysis. To establish economic interrelations, the matrix of import and export of various types of agricultural products in the EEU member countries has been proposed. © 2019, World Scientific and Engineering Academy and Society. All rights reserved

Refractory contact to a-SiC produced by laser technology methods

Developed in the paper are method and technological scheme to obtain ohmic contacts (OC) to a-SiC(:N), Nd - Na ~1 - 3.10¹⁸ cm⁻³ by pulse laser deposition (PLD) of multilayer structures Ni/W/Si₃N₄/W and the following laser annealing (LA). When using an YAG:Nd³⁺ laser, threshold levels and optimal regimes for laser induced diffusion and laser annealing of contacts were determined. It is shown that the Q-switched regime with combined exposure of the fundamental (λ = 1.06 mm) and second (λ = 0.53 mm) harmonics are found as optimal for obtaining minimal contact resistance when YAG:Nd³⁺ laser is used. It is shown that the threshold levels of visual by observed irreversible changes in contact resistance coincide with those of current-voltage characteristics (CVC) and is found to lie in the range area PthCV = = (3 - 8)*10⁷ W*cm⁻² in dependence on thickness of deposited metal layers. The phase transition existence has been established in the process of laser induced modification and annealing on the basis of observed changes in the CVC character and results of surface investigations by Atomic Force Microscopy (AFM). Typical values of resistivity rc of non-fused OC obtained to a-SiC based on Ni/W/Si₃N₄/W structures were close to the value rc ~ (3 ÷ 4)*10⁻⁴W*cm². The contact withstood the current density 104 A*cm⁻² for 100 hours

Preliminary Results from the CMD-2 Detector

A new general-purpose detector CMD-2 (calorimetric magnetic detector has started experiments at the upgraded e[sup [plus]]e[sup [minus]] collider VEPP-2M (collider for electron-positron beams) at Novosibirsk. During early runs an integrated luminosity of about 400 inverse nanobarns has been collected in the center of mass energy range 400[endash]1030 MeV

Functional supramolecular systems: Design and applications

The interest in functional supramolecular systems for the design of innovative materials and technologies, able to fundamentally change the world, is growing at a high pace. The huge array of publications that appeared in recent years in the global literature calls for systematization of the structural trends inherent in the formation of these systems revealed at different molecular platforms and practically useful properties they exhibit. The attention is concentrated on the topics related to functional supramolecular systems that are actively explored in institutes and universities of Russia in the last 10-15 years, such as the chemistry of host-guest complexes, crystal engineering, self-assembly and self-organization in solutions and at interfaces, biomimetics and molecular machines and devices