Suchergebnisse

The conducted research reveals the role of the metallurgical complex of Ukraine in world production and export of steel. Its development indicates inertia and is in a pre-crisis condition. But, at the same time, there are prospects for the development of the enterprises of the metallurgical complex of Ukraine, which appears to be the purpose of the study along with an assessment of the dynamics of the development of the metallurgical complex of Ukraine regarding the internal and external factors of influence on it. Therefore, the object of the research is the current state of development of the metallurgical complex of Ukraine. For this purpose, the main methods of steel processing and fuel consumption for their melting are determined, which, thus, emphasizes the extraordinary energy intensity and cost structure of steel production in Ukraine due to 21.4% of processing in open-hearth furnaces. As a result, on the basis of the comparative analysis, the structure of production was characterized by the degree of steel processing, which indicated the inertia of the development of the industry on the principle of total exploitation of available resources. Through systematic structural analysis, the types of economic activity, the results of the enterprises, which were taken into account in the research of the development of the metallurgical complex of Ukraine and identified their implementation under the imperative incremental destructive factors of the internal and external environment, were identified. With the help of empirical research, in the institutional environment instability of normative legal provision, regulatory restrictions on FDI inflow and investment protectionism in metallurgy were revealed. The critical dependence of the industry on demand in foreign markets based on the export orientation of raw materials is established. For example, it has been determined that at the expense of products below the average technological capacity, almost a quarter of the export basket of Ukraine was formed. It was found that metallurgical production is a zone of interests of powerful industrial and banking private business groups of residents and non-residents. The absence of a state-owned joint-stock company or a holding company in Ukraine with a main type of activity in the investigated industries is emphasized.

At present, great importance is attached to the problem of maintaining the professional health of the working-age population and prolonging professional longevity in the world and in the Russian Federation. This problem has become especially urgent in recent years, in connection with the change in the country's retirement age.

We present a combined experimental and theoretical study of the two-dimensional electron states at the iridium-silicide surface of the antiferromagnet GdIr2Si2 above and below the Néel temperature. Using angle-resolved photoemission spectroscopy (ARPES) we find a significant spin-orbit splitting of the surface states in the paramagnetic phase. By means of ab initio density-functional-theory (DFT) calculations we establish that the surface electron states that reside in the projected band gap around the ¯¯¯¯M point exhibit very different spin structures which are governed by the conventional and the cubic Rashba effect. The latter is reflected in a triple spin winding, i.e., the surface electron spin reveals three complete rotations upon moving once around the constant energy contours. Below the Néel temperature, our ARPES measurements show an intricate photoemission intensity picture characteristic of a complex magnetic domain structure. The orientation of the domains, however, can be clarified from a comparative analysis of the ARPES data and their DFT modeling. To characterize a single magnetic domain picture, we resort to the calculations and scrutinize the interplay of the Rashba spin-orbit coupling field with the in-plane exchange field, provided by the ferromagnetically ordered 4f moments of the near-surface Gd layer. ; This work was supported by the German Research Foundation (DFG) through Grants No. KR3831/5-1, No. LA655/20-1, No. GRK1621, No. SFB1143 (Project No. 247310070). We acknowledge support from the Russian Foundation for Basic Research (Grant No. 20-32-70127) and Saint Petersburg State University (Grant No. ID 51126254). M.M.O. acknowledges the support by Spanish Ministerio de Ciencia e Innovación (Grant No. PID2019-103910GB-I00). A.Yu.V. acknowledges the support by RFBR, Project No. 19-32-90251. D.V.V. acknowledges financial support from the Spanish Ministry of Economy (MAT-2017-88374-P). We acknowledge MAX IV Laboratory for time on the Bloch Beamline under Proposal 20190824. Research conducted at MAX IV, a Swedish national user facility, is supported by the Swedish Research council under contract 2018-07152, the Swedish Governmental Agency for Innovation Systems under contract 2018-04969, and Formas under contract 2019-02496. The authors gratefully acknowledge the GWK support for funding this work by providing computing time through the Center for Information Services and HPC (ZIH) at TU Dresden. ; Peer reviewed

Spin-orbit interaction and structure inversion asymmetry in combination with magnetic ordering is a promising route to novel materials with highly mobile spin-polarized carriers at the surface. Spin-resolved measurements of the photoemission current from the Si-terminated surface of the antiferromagnet TbRh2Si2 and their analysis within an ab initio one-step theory unveil an unusual triple winding of the electron spin along the fourfold-symmetric constant energy contours of the surface states. A two-band k⋅p model is presented that yields the triple winding as a cubic Rashba effect. The curious in-plane spin-momentum locking is remarkably robust and remains intact across a paramagnetic-antiferromagnetic transition in spite of spin-orbit interaction on Rh atoms being considerably weaker than the out-of-plane exchange field due to the Tb 4f moments. ; This work was supported by the German Research Foundation (Grants No. KR-3831/5-1, No. LA655/20-1, GRK1621, Fermi-NESt No. ANR-16-CE92-0018, and SFB1143, project-id 247310070) and the Spanish Ministry of Science, Innovation, and Universities (Grant Nos. FIS2016-76617-P and MAT-2017-88374-P). We also acknowledge funding from the Department of Education of the Basque government (Grant No. IT1164-19), St. Petersburg State University (Project ID 51126254), and the Russian Foundation for Basic Research (Grant No. 20-32-70127). The SR-ARPES experiments at HiSOR were performed with the approval of the Proposal Assessing Committee of the Hiroshima Synchrotron Radiation Center (Proposal No. 18BG023). We also acknowledge the Impuls-und Vernetzungsfonds der Helmholtz Gemeinschaft (Grant No. HRSF-0067) ; Peer reviewed