326 research outputs found

    Possible impact of corporate governance profile on a Russian bank valuation

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    This paper aims at explaining the differences in valuation of banking firms in Russia through the impact of selected elements of corporate governance. We rely upon value-based management theory to test the hypothesis that expenses on corporate governance system create shareholder value. The price at which share stakes are acquired by strategic foreign investors is for us a criterion of market-proven value, so we use the standard valuation tool, i.e. price-to-book-value of equity (P/BV) multiple, as the dependent variable. The set of corporate governance parameters whose materiality for a would-be external investor we would like to test includes: the degree of concentration of ownership and control; maturity of corporate governing bodies; degree of Board independence; qualification of external auditors; stability of governing bodies (Management Board and Board of Directors); and availability of external credit ratings from the world's leading rating agencies. We test our approach on a sample of acquisition deals and public offerings over the period 2004-2008 that we develop for the first time. Firstly, we find out which factors are statistically significant and relevant to a bank's selling price. Secondly, a least squares multiple linear regression model is devised to check how each individual variable impacts the dependent variable. We discover that external investors attach value to high concentration of ownership, external credit rating coverage, stability of the Board of Directors, and involvement of well-established external auditors. Investors of a strategic nature tend to pay a higher acquisition premium. Independence of the Board of Directors might be perceived by external strategic investors as a disadvantage and might destroy shareholder value

    Проектирование установки по переработке и утилизации нефтепродуктов

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    Современное развитие нефтяной отрасли предполагает наличие ресурсоэффективныхтехнологий, которые базируются на технических, экономических и экологических принципах.Нарушение технологических режимов транспортировки углеводородов может привести кневосполнимым потерям природных ресурсов и нанести существенный экологический ущерб. Поэтомумеждународные экологические стандарты ИСО 14000 предполагают повышенные видыответственности к предприятиям, допустившим указанные нарушения. Тем не менее, нефтяныекомпании ежегодно несут серьезные финансовые затраты, связанные с аварийными или чрезвычайнымиситуациями при транспорте нефти и нефтепродуктов. В связи с вышеуказанным, возникаетнеобходимость в совершенствовании существующих и разработке новых эффективных и быстрореализуемых технологий локализации и утилизации нефтяных разливов

    Spin-glass state and long-range magnetic order in Pb(Fe1/2Nb1/2)O3

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    We have investigated the magnetic ground-state of the multiferroic relaxor ferroelectric \pfn with μ\muSR spectroscopy and neutron scattering. We find that a transition to a partially disordered phase occurs below T=20 K that coexists with long-range antiferromagnetic ordering. The disordered phase resembles a spin-glass. No clustering of magnetic ions could be evidenced by μ\muSR so that the coexistence appears homogeneous in the sample

    Development of Ferroelectric Order in Relaxor (1-x)Pb(Mg1/3Nb2/3)O3 - xPbTiO3

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    The microstructure and phase transition in relaxor ferroelectric Pb(Mg1/3Nb2/3)O3 (PMN) and its solid solution with PbTiO3 (PT), PMN-xPT, remain to be one of the most puzzling issues of solid state science. In the present work we have investigated the evolution of the phase symmetry in PMN-xPT ceramics as a function of temperature (20 K < T < 500 K) and composition (0 <= x <= 0.15) by means of high-resolution synchrotron x-ray diffraction. Structural analysis based on the experimental data reveals that the substitution of Ti^4+ for the complex B-site (Mg1/3Nb2/3)^4+ ions results in the development of a clean rhombohedral phase at a PT-concentration as low as 5%. The results provide some new insight into the development of the ferroelectric order in PMN-PT, which has been discussed in light of the kinetics of polar nanoregions and the physical models of the relaxor ferroelectrics to illustrate the structural evolution from a relaxor to a ferroelectric state.Comment: Revised version with updated references; 9 pages, 4 figures embedde

    Magnetocaloric effect in the high-temperature antiferromagnet YbCoC2

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    The magnetic HH-TT phase diagram and magnetocaloric effect in the recently discovered high-temperature heavy-fermion compound YbCoC2_2 have been studied. With the increase in the external magnetic field YbCoC2_2 experiences the metamagnetic transition and then transition to the ferromagnetic state. The dependencies of magnetic entropy change -ΔSm(T)\Delta S_m (T) have segments with positive and negative magnetocaloric effects for ΔH6\Delta H \leq 6~T. For ΔH=9\Delta H = 9~T magnetocaloric effect becomes positive with a maximum value of -ΔSm(T)\Delta S_m (T) is 4.1 J / kg K and a refrigerant capacity is 56.6 J / kg

    Effect of high pressure on multiferroic BiFeO3

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    We report experimental evidence for pressure instabilities in the model multiferroic BiFeO3 and namely reveal two structural phase transitions around 3 GPa and 10 GPa by using diffraction and far-infrared spectroscopy at a synchrotron source. The intermediate phase from 3 to 9 GPa crystallizes in a monoclinic space group, with octahedra tilts and small cation displacements. When the pressure is further increased the cation displacements (and thus the polar character) of BiFeO3 is suppressed above 10 GPa. The above 10 GPa observed non-polar orthorhombic Pnma structure is in agreement with recent theoretical ab-initio prediction, while the intermediate monoclinic phase was not predicted theoretically.Comment: new version, accepted for publication in Phys. Rev.

    Carcinogenicity Screening of Chemicals Using Positron Annihilation Spectroscopy

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    Chemical carcinogens are the main cause of cancer. Many thousands of new chemicals are synthesized annually in the world, unknown part of them is carcinogens. There are several methods, which are currently used for testing carcinogenicity. The fastest arephysicochemical methods. We suggest the method of fast carcinogen screening using the positron annihilation spectroscopy (PAS). It is based on the fact that the presence of carcinogens, being strong electrophiles, significantly decreases positronium (Ps) formation probability. This quantity can be measured by means of conventional PAS techniques: positron annihilation lifetime spectroscopy (PALS), angular correlation of annihilation radiation (ACAR) or Doppler broadening of annihilation radiation (DBAR). It is also possible to evaluate anti-carcinogenic properties of chemicals using the anti-inhibition effect of Ps formation. Keywords: carcinogen, electrophilicity, positron annihilation spectroscopy, positroniu

    Barkhausen Noise in a Relaxor Ferroelectric

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    Barkhausen noise, including both periodic and aperiodic components, is found in and near the relaxor regime of a familiar relaxor ferroelectric, PbMg1/3_{1/3}Nb2/3_{2/3}O3_3, driven by a periodic electric field. The temperature dependences of both the amplitude and spectral form show that the size of the coherent dipole moment changes shrink as the relaxor regime is entered, contrary to expectations based on some simple models.Comment: 4 pages RevTeX4, 5 figures; submitted to Phys Rev Let

    Direct observation of the formation of polar nanoregions in Pb(Mg1/3_{1/3}Nb2/3_{2/3})O3_3 using neutron pair distribution function analysis

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    Using neutron pair distribution function (PDF) analysis over the temperature range from 1000 K to 15 K, we demonstrate the existence of local polarization and the formation of medium-range, polar nanoregions (PNRs) with local rhombohedral order in a prototypical relaxor ferroelectric Pb(Mg1/3_{1/3}Nb2/3_{2/3})O3_3. We estimate the volume fraction of the PNRs as a function of temperature and show that this fraction steadily increases from 0 % to a maximum of \sim 30% as the temperature decreases from 650 K to 15 K. Below T\sim200 K the PNRs start to overlap as their volume fraction reaches the percolation threshold. We propose that percolating PNRs and their concomitant overlap play a significant role in the relaxor behavior of Pb(Mg1/3_{1/3}Nb2/3_{2/3})O3_3.Comment: 4 pages, 3 figure

    Phonon and magnon scattering of antiferromagnetic Bi2Fe4O9

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    The phonon structure of antiferromagnetic Bi2Fe4O9 (space group Pbnm No. 55, TN≈240  K) was studied theoretically by calculations of lattice dynamics and experimentally between 10 and 300 K by polarized Raman spectroscopy. Most of the 12Ag+12B1g+9B2g+9B3g Raman modes were unambiguously identified. Strong second-order scattering was observed for ab-plane-confined incident and scattered light polarizations. In addition to the phonon-scattering, broad Raman bands with typical characteristics of magnon scattering appear below TN. The magnon bands are analyzed on the basis of magnetic structure of Bi2Fe4O9 and attributed to two- magnon excitations
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