547 research outputs found

    St Petersburg Business Information Centres and Their Role in Increasing the Efficiency of International Business Activities

    Full text link
    The Ministry of Foreign Affairs of the Russian Federation acknowledges the significant contribution of regions to the development of the state’s foreign policy. An increase in innovative production, a commitment to achieve complete import substitution, and the development of measures to promote non-raw material export are the principal objectives established by the state for its regions. The current trends in world economy and the geopolitical situation formulate new goals and objectives for regions and suggest the creation of innovative and universal mechanisms to increase the efficiency of international economic activities, promotion of a positive image of Saint Petersburg and other regions of the Russian Northwest. The article analyses the activities of Saint Petersburg business information centres abroad, similar experience of other Russian regions, and prerequisites for reforming the institution of regional offices abroad. In the course of the study, new theoretical and methodological questions as to improving the regulatory framework for development and functioning of Russian regional offices abroad, the use of public-private partnership mechanism in foreign economic activities and information technologies of positive image promotion were formulated

    Competitiveness of the economies of border regions

    Full text link
    The article is dedicated to the problem of competitiveness of border regions as subjects of the Russian Federation having specific characteristics. The authors focus on the stages, during which border regions build their competitiveness, as well as analyse certain indices characterizing it. They examine the role of these regions in the development of international trade and economic relations, cross-border cooperation and international integration, taking the North-west federal district and the Republic of Karelia as a case-study. The article describes the mechanisms of building and increasing competitiveness of border regions in today’s Russia both in general and, particularly, in the Republic of Karelia as a border region of the North-west federal district

    Character of jet flows in mass-spectrometric interfaces at various pressures and chamber lengths

    Get PDF
    Samples-in particular, of bioorganic matter—are usually introduced into a mass spectrometer from atmosphere to high vacuum via a gasdynamic interface that represents a chamber with intermediate pressure or a system of chambers with gradually decreasing pressure. Transformation of the character of an expanding jet flow in a single-chamber interface has been studied as dependent on the chamber length and pressure. Knowledge of this character allows the system parameters to be most effectively used so as to ensure high ion transmission and decrease mass discriminatio

    Quantized Rotation of Atoms From Photons with Orbital Angular Momentum

    Get PDF
    We demonstrate the coherent transfer of the orbital angular momentum of a photon to an atom in quantized units of hbar, using a 2-photon stimulated Raman process with Laguerre-Gaussian beams to generate an atomic vortex state in a Bose-Einstein condensate of sodium atoms. We show that the process is coherent by creating superpositions of different vortex states, where the relative phase between the states is determined by the relative phases of the optical fields. Furthermore, we create vortices of charge 2 by transferring to each atom the orbital angular momentum of two photons.Comment: New version, 4 pages and 3 figures, accepted for publication in Physical Review Letter

    Spin-polarized tunneling spectroscopic studies of the intrinsic heterogeneity and pseudogap phenomena in colossal magnetoresistive manganite La_{0.7}Ca_{0.3}MnO_{3}

    Get PDF
    Spatially resolved tunneling spectroscopic studies of colossal magnetoresistive (CMR) manganite La0.7Ca0.3MnO3\rm La_{0.7}Ca_{0.3}MnO_3 (LCMO) epitaxial films on (LaAlO3)0.3(Sr2AlTaO6)0.7\rm (LaAlO_3)_{0.3}(Sr_2AlTaO_6)_{0.7} substrate are investigated as functions of temperature, magnetic field and spin polarization by means of scanning tunneling spectroscopy. Systematic surveys of the tunneling spectra taken with Pt/Ir tips reveal spatial variations on the length scale of a few hundred nanometers in the ferromagnetic state, which may be attributed to the intrinsic heterogeneity of the manganites due to their tendency towards phase separation. The electronic heterogeneity is found to decrease either with increasing field at low temperatures or at temperatures above all magnetic ordering temperatures. On the other hand, spectra taken with Cr-coated tips are consistent with convoluted electronic properties of both LCMO and Cr. In particular, for temperatures below the magnetic ordering temperatures of both Cr and LCMO, the magnetic-field dependent tunneling spectra may be quantitatively explained by the scenario of spin-polarized tunneling in a spin-valve configuration. Moreover, a low-energy insulating energy gap 0.6\sim 0.6 eV commonly found in the tunneling conductance spectra of bulk metallic LCMO at T0T \to 0 may be attributed to a surface ferromagnetic insulating (FI) phase, as evidenced by its spin filtering effect at low temperatures and vanishing gap value above the Curie temperature. Additionally, temperature independent pseudogap (PG) phenomena existing primarily along the boundaries of magnetic domains are observed in the zero-field tunneling spectra. The PG becomes strongly suppressed by applied magnetic fields at low temperatures when the tunneling spectra of LCMO become highly homogeneous. These findings suggest that the occurrence PG is associated with the electronic heterogeneity of the manganites.Comment: 15 pages, 15 figures. Published in Physical Review B. Corresponding author: Nai-Chang Yeh (E-mail: [email protected]

    Formation of metallic magnetic clusters in a Kondo-lattice metal: Evidence from an optical study

    Get PDF
    Magnetic materials are usually divided into two classes: those with localised magnetic moments, and those with itinerant charge carriers. We present a comprehensive experimental (spectroscopic ellipsomerty) and theoretical study to demonstrate that these two types of magnetism do not only coexist but complement each other in the Kondo-lattice metal, Tb2PdSi3. In this material the itinerant charge carriers interact with large localised magnetic moments of Tb(4f) states, forming complex magnetic lattices at low temperatures, which we associate with self-organisation of magnetic clusters. The formation of magnetic clusters results in low-energy optical spectral weight shifts, which correspond to opening of the pseudogap in the conduction band of the itinerant charge carriers and development of the low- and high-spin intersite electronic transitions. This phenomenon, driven by self-trapping of electrons by magnetic fluctuations, could be common in correlated metals, including besides Kondo-lattice metals, Fe-based and cuprate superconductors.Comment: 30 pages, 6 Figure

    Degrees of Autostability Relative to Strong Constructivizations for Boolean Algebras

    Get PDF
    © 2016 Springer Science+Business Media New YorkIt is proved that for every computable ordinal α, the Turing degree 0(α) is a degree of autostability of some computable Boolean algebra and is also a degree of autostability relative to strong constructivizations for some decidable Boolean algebra. It is shown that a Harrison Boolean algebra has no degree of autostability relative to strong constructivizations. It is stated that the index set of decidable Boolean algebras having degree of autostability relative to strong constuctivizations is ∏11-complete

    Categoricity Spectra for Polymodal Algebras

    Get PDF
    © 2016, Springer Science+Business Media Dordrecht.We investigate effective categoricity for polymodal algebras (i.e., Boolean algebras with distinguished modalities). We prove that the class of polymodal algebras is complete with respect to degree spectra of nontrivial structures, effective dimensions, expansion by constants, and degree spectra of relations. In particular, this implies that every categoricity spectrum is the categoricity spectrum of a polymodal algebra

    Categoricity Spectra for Polymodal Algebras

    Get PDF
    © 2016 Springer Science+Business Media DordrechtWe investigate effective categoricity for polymodal algebras (i.e., Boolean algebras with distinguished modalities). We prove that the class of polymodal algebras is complete with respect to degree spectra of nontrivial structures, effective dimensions, expansion by constants, and degree spectra of relations. In particular, this implies that every categoricity spectrum is the categoricity spectrum of a polymodal algebra

    Degrees of Autostability Relative to Strong Constructivizations for Boolean Algebras

    Get PDF
    © 2016, Springer Science+Business Media New York.It is proved that for every computable ordinal α, the Turing degree 0(α)is a degree of autostability of some computable Boolean algebra and is also a degree of autostability relative to strong constructivizations for some decidable Boolean algebra. It is shown that a Harrison Boolean algebra has no degree of autostability relative to strong constructivizations. It is stated that the index set of decidable Boolean algebras having degree of autostability relative to strong constuctivizations is ∏11-complete
    corecore