TRANSNATIONALISM ONLINE: EXPLORING MIGRATION PROCESSES WITH LARGE DATA SETS

The exponential growth of online technologies in everyday life transforms the very contours of social phenomena, processes, and institutions well known to sociologists. We discuss these transformations in two interrelated areas: transnational migration and extremism. First, the paper proposes an approach to examine «transnationalism online» as a sub-set of transnational migration studies. Second, it presents a critical review of how contemporary scholars study extremist activities and discourse of those who are involved in migration with a special focus on online manifestations of extremism. In a concluding part of the paper we present theoretical and methodological comments on the paths in examining the «dark side» of transnationalism online

Highly wear-resistant and biocompatible carbon nanocomposite coatings for dental implants

Diamond-like carbon coatings are increasingly used as wear-protective coatings for dental implants, artificial joints, etc. Despite their advantages, they may have several weak points such as high internal stress, poor adhesive properties or high sensitivity to ambient conditions. These weak points could be overcome in the case of a new carbon nanocomposite coating (CNC) deposited by using a C60 ion beam on a Co/Cr alloy. The structure of the coatings was investigated by Raman and XPS spectroscopy. The wear resistance was assessed by using a reciprocating tribotester under the loads up to 0.4 N in both dry and wet sliding conditions. Biocompatibility of the dental implants was tested in vivo on rabbits. Biocompatibility, bioactivity and mechanical durability of the CNC deposited on a Co/Cr alloy were investigated and compared with those of bulk Co/Cr and Ti alloys. The wear resistance of the CNC was found to be 250e650 fold higher compared to the Co/Cr and Ti alloys. Also, the CNC demonstrated much better biological properties with respect to formation of new tissues and absence of negative morphological parameters such as necrosis and demineralization. Development of the CNC is expected to aid in significant improvement of lifetime and quality of implants for dental applications

The use of magnetic coercivity method to diagnose crane metalware

The recent problem of estimating the residual life of metal structures for handling equipment is actual, since more than 90% exhausted its regulatory resources. The current paper proposes an approach to solve this problem by using the coercive force. It is shown that in order to determinate damage of dangerous element of crane it is needed to know not only a coercive force but also a stress. Mathematical model is proposed to determine the damage of metal ware

Agroecological aspects of application of

This article submits results of laboratory and field experiments on the effect of an auxin-producing bacterial strain Pseudomonas sp. DA1.2 in comparison with Pseudomonas koreensis IB-4 on wheat plants in conjunction with the “Chistalan” herbicide treatment. Our work shows the positive effect of bacterial treatments on plant growth, the relative water content in leaves and the role of bacteria in the redistribution of ABA and IAA in wheat shoots under conditions of herbicidal stress. Application of Pseudomonas sp. DA1.2 together with the herbicide in the field of the steppe zone led to an increase in yield by 20% relative to the control variant. This bacterial strain helps to overcome herbicidal stress and is a promising agent for improving the technology of using synthetic auxins herbicides

Recognition of S···Cl Chalcogen Bonding in Metal-Bound Alkylthiocyanates

Reaction of K₂[PtCl₄] with excess AlkSCN in water gives the alkylthiocyanate complexes <i>trans</i>-[PtCl₂­(AlkSCN)₂] (Alk = Et <b>1</b>, ^<i>n</i>Pr <b>2</b>; 80–85%). These species were studied, in particular, by X-ray crystallography. In the solid state, both <b>1</b> and <b>2</b> exhibit the previously unreported S···Cl chalcogen bonding, which consolidates the complexes into networks and leads to layered structures. Theoretical density functional theory calculations and Bader’s atoms in molecules analysis demonstrated two types of intermolecular interactions in tetramer (<b>1</b>)₄, viz. the S···Cl chalcogen and the H···Cl hydrogen bonds. Despite that each particular S···Cl or H···Cl bonding is weak with the estimated energy of 1–2 kcal/mol, altogether they play a crucial role in the stabilization of the S₂Cl₂ fragment in (<b>1</b>)₄, the basis set of superposition error corrected interaction energy being −12.8 kcal/mol per monomer complex molecule. The chalcogen bonding and the rhomboidal structure of the S₂Cl₂ fragment can be interpreted in terms of electrostatic arguments as a result of the interaction between the belt of negative electrostatic potential around the Cl atoms and the sulfur σ-holes. The natural bond orbital analysis revealed that both LP­(S) → LP*­(Pt)/​σ*­(Pt–N)/​σ*­(Pt–Cl) and LP­(Cl) → σ*­(S–C) types of hyperconjugative charge transfers are important in the chalcogen bonding

Extremely Polysubstituted Magnetic Material Based on Magnetoplumbite with a Hexagonal Structure: Synthesis, Structure, Properties, Prospects

Crystalline high-entropy single-phase products with a magnetoplumbite structure with grains in the &#956;m range were obtained using solid-state sintering. The synthesis temperature was up to 1400 &#176;C. The morphology, chemical composition, crystal structure, magnetic, and electrodynamic properties were studied and compared with pure barium hexaferrite BaFe12O19 matrix. The polysubstituted high-entropy single-phase product contains five doping elements at a high concentration level. According to the EDX data, the new compound has a formula of Ba(Fe6Ga1.25In1.17Ti1.21Cr1.22Co1.15)O19. The calculated cell parameter values were a = 5.9253(5) &#197;, c = 23.5257(22) &#197;, and V = 715.32(9) &#197;3. The increase in the unit cell for the substituted sample was expected due to the different ionic radius of Ti/In/Ga/Cr/Co compared with Fe3+. The electrodynamic measurements were performed. The dielectric and magnetic permeabilities were stable in the frequency range from 2 to 12 GHz. In this frequency range, the dielectric and magnetic losses were &#8722;0.2/0.2. Due to these electrodynamic parameters, this material can be used in the design of microwave strip devices