Comprehensive study of physical and chemical behavior of vanadium in molten alkali metal chlorides

Электродные процессы с участием соединений ванадия были изучены при 690-860 oC в расплавах на основе (Na-K)Clэкв с использованием электрохимических стационарных и нестационарных методов: хроноамперометрия, хронопотенциометрия, циклическая и квадратно-волновая вольтамперометрия. Катодное восстановление ванадия в расплавах (Na-K)Clэкв-VCl3 включает 2 стадии: одноэлектронная V3+→V2+ и двухэлектронная V2+→V реакции. При постоянно приложенном токе обе стадии контролируются диффузией. Механизм электродных реакций остается сходным при вольтамперометрических измерениях на скоростях развертки ниже 200 мВ/с. При высоких скоростях развертки потенциала реакции протекают в смешанном диффузионно-кинетическом режиме. Анализ ОВ-процессов в хлоридных расплавах показал, что комплексные ионы V(II) и V(III) устойчивы в данных средах.The electrode processes involving vanadium species were studied at 690-860 oC in NaCl-KCl-based melts employing electrochemical stationary and non-stationary methods: chronoamperometry, chronopotentiometry, cyclic and square-wave voltammetry. Cathodic reduction of vanadium in VCl3-NaCl-KCl melts involves two steps: one-electron V3+→V2+ and two-electron V2+→V reactions. Under a constant applied current both stages are diffusion-controlled. The mechanism of the electrode reactions remains the same in voltammetry measurements at polarization rates below ca. 200 mV/sec. At higher potential scan rates the reactions proceed in a mixed diffusion- and kinetic-controlled regime. Analysis of the red-ox processes in chloride melts showed that V(II) and V(III) complex chloride ions are stable in these media.Программа развития УрФУ на 2013 год (п.2.1.1.1

Multi-wavelength Emission from the Fermi Bubble III. Stochastic (Fermi) Re-Acceleration of Relativistic Electrons Emitted by SNRs

We analyse the model of stochastic re-acceleration of electrons, which are emitted by supernova remnants (SNRs) in the Galactic Disk and propagate then into the Galactic halo, in order to explain the origin on nonthermal (radio and gamma-ray) emission from the Fermi Bubbles (FB). We assume that the energy for re-acceleration in the halo is supplied by shocks generated by processes of star accretion onto the central black hole. Numerical simulations show that regions with strong turbulence (places for electron re-acceleration) are located high up in the Galactic Halo about several kpc above the disk. The energy of SNR electrons that reach these regions does not exceed several GeV because of synchrotron and inverse Compton energy losses. At appropriate parameters of re-acceleration these electrons can be re-accelerated up to the energy 10E12 eV which explains in this model the origin of the observed radio and gamma-ray emission from the FB. However although the model gamma-ray spectrum is consistent with the Fermi results, the model radio spectrum is steeper than the observed by WMAP and Planck. If adiabatic losses due to plasma outflow from the Galactic central regions are taken into account, then the re-acceleration model nicely reproduces the Planck datapoints.Comment: 33 pages, 8 figures, accepted by Ap

LEADING ATOPIC PATHOLOGIES IN CHILDREN ON THE TERRITORY OF MYKOLAIV REGION

The article is devoted to allergic diseases among children of the Nikolaev area, first of all bronchial asthma of an atopic form.  The dynamics of the prevalence of allergic diseases is analyzed, the most rational methods of diagnosis and treatment of allergopathology are determined.  Data on hospitalization in the allergy department, the structure of diagnoses that are most often clinically established in children with allergy pathology are presented.  The materials will be of interest to allergists, pulmonologists, immunologists, family doctors and pediatricians.Key words: allergy, bronchial asthma, allergic diseases, atopy, allergology, pediatrics

Analytical and numerical studies of central galactic outflows powered by tidal disruption events -- a model for the Fermi bubbles?

Capture and tidal disruption of stars by the supermassive black hole in the Galactic center (GC) should occur regularly. The energy released and dissipated by this processes will affect both the ambient environment of the GC and the Galactic halo. A single star of super-Eddington eruption generates a subsonic out ow with an energy release of more than $10^{52}$ erg, which still is not high enough to push shock heated gas into the halo. Only routine tidal disruption of stars near the GC can provide enough cumulative energy to form and maintain large scale structures like the Fermi Bubbles. The average rate of disruption events is expected to be $10^{-4}$ ~ $10^{-5}$ yr$^{-1}$, providing the average power of energy release from the GC into the halo of dW/dt ~ 3*10$^{41}$ erg/s, which is needed to support the Fermi Bubbles. The GC black hole is surrounded by molecular clouds in the disk, but their overall mass and filling factor is too low to stall the shocks from tidal disruption events significantly. The de facto continuous energy injection on timescales of Myr will lead to the propagation of strong shocks in a density stratified Galactic halo and thus create elongated bubble-like features, which are symmetric to the Galactic midplane.Comment: 11 pages, 5 figures. The title and abstract have been changed. Accepted by Astrophysical Journa

Particle acceleration and the origin of gamma-ray emission from Fermi Bubbles

Fermi LAT has discovered two extended gamma-ray bubbles above and below the galactic plane. We propose that their origin is due to the energy release in the Galactic center (GC) as a result of quasi-periodic star accretion onto the central black hole. Shocks generated by these processes propagate into the Galactic halo and accelerate particles there. We show that electrons accelerated up to ~10 TeV may be responsible for the observed gamma-ray emission of the bubbles as a result of inverse Compton (IC) scattering on the relic photons. We also suggest that the Bubble could generate the flux of CR protons at energies > 10^15 eV because the shocks in the Bubble have much larger length scales and longer lifetimes in comparison with those in SNRs. This may explain the the CR spectrum above the knee.Comment: 5 pages, 4 figures. Expanded version of the contribution to the 32nd ICRC, Beijing, #0589. To appear in the proceeding