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2009Chudoba V.,a,b Fomichev A. S.,a Grigorenko L. V.,a,c Golovkov M. S.,a Gorshkov V. A.,a Krupko S. A.,a Oganessian Y. T.,a Rodin A. M,a Sidorchuk S. I.,a Slepnev R. S.,a Stepantsov S. V.,a Te r- Akopian G. M.,a Wolski R.,a,d Pang D.,a,e Korsheninnikov A. A.,c Kuzmin E. A.,c Nikolskii E. Y.,c Novatskii B. G.,c Stepanov D. N.,c Roussel - Chomaz P.,e Mittig W.,e,f Ninane A.,g Hanappe F.,h Stuttge L.,i Yukhimchuk A. A.,j Vinogradov Y. I.,j Perevozchikov V. V.,j Grishechkin S. K.j Low - energy spectra of 8He and 10He studied in ( t, p ) type reactions in inverse kinematics // Acta Physica Polonica, 2009, Ser B, Volume 40, Issue 3, Pages 899 - 902 a Flerov Laboratory of Nuclear reactions, JINR, Russian Federation Missing mass spectra for 8He and 10He obtained in the reactions 3H ( 6He, p ) 8He and 3H ( 8He, p ) 10He, respectively, are presented. Korshunov A., Kudasov Y., Maslov D., Pavlov V. Dynamics of magnetization in frustrated spin - chain systems: Ca3Co2O6 // Diffusion and Defect Data Pt.B: Solid State Phenomena, 2009, Volume 152 - 153, Pages 225 - 228 RFNC - VNIIEF, Sarov, Russian Federation A two - dimensional Ising - like model for the triangular spin - chain lattice, where each spin chain is treated as a rigid superspin, is proposed to investigate the dynamics of magnetization in frustrated triangular spin - chain systems. The superspins are assumed to interact with the nearest neighbours and external agency ( heat reservoir and external magnetic field ) that causes them to change their states randomly with time. A probability of a single spin - flip process is assumed in a Glauber - like form. This technique allows describing the steps in the magnetization curves observed in Ca3Co2O6 and their dependence on the magnetic field sweep rate and temperature. Kudasov Y. B. Magnetic phase diagram and magnetization dynamics of frustrated spin - chain compounds // Diffusion and Defect Data Pt.B: Solid State Phenomena, 2009, Volume 152 - 153, Pages 233 - 236 RFNC - VNIIEF, Sarov, Russian Federation The magnetic phase diagram of Ising spin chains packed into the frustrated triangular lattice is discussed. A structure of a low - temperature phase depends strongly on interactions between the next - to - nearest - neighbor chains because they lift the degeneracy of the triangular AFM Ising model. That is why, a variety of low - temperature phases is observed in CsCoCl3, Ca3Co2O6, and Sr5Rh4O12. On the contrary, the high - temperature phase ( honeycomb AFM structure ) is unique. The frustrated Ising chain systems demonstrate an unusual and very slow magnetization dynamics. A model of the magnetization dynamics similar to the Glauber theory is developed. Fomichev A. S.,a Grigorenko L. V.,a,b Golovkov M. S.,a Ter - Akopian G.M.,a Oganessian Y. T.,a Gorshkov V. A.,a Krupko S. A.,a Rodin A. M.,a Sidorchuk S. I.,a Slepnev R. S.,a Stepantsov S. V.,a Wolski R.,a,c Chudoba V.,a Korsheninnikov A. A.,b Kuzmin E. A.,b Nikolskii E. Y.,b,j Novatskii B. G.,b Stepanov D. N.,b Roussel - Chomaz, P.,d Mittig W.,d,i Pang D.,a,d Ninane A.,e Hanappe F.,f Stuttge L.,g Yukhimchuk A. A.,h Perevozchikov V. V.,h Vinogradov Y. I.,h Grishechkin S. K.,h Zlatoustovskiy S. V.h Properties of very n - rich He isotopes // European Physical Journal, 2009, Ser A, Volume 42, Issue 3, Pages 465 - 469 a Flerov Laboratory of Nuclear Reactions, JINR, RU - 141980 Dubna, Russian Federation Low - energy spectra of the 8,10He nuclei were investigated in the ( t, p ) - type reactions at small centre - of - mass angles using ~ 25 AMeV beams of 6He and 8He nuclei. The 0+ ground state ( g. s. ) of 8He and excited states, 2+ at 3,6 - 3,9 MeV and ( 1+ ) at 5,3 - 5,5 MeV, were populated with cross - sections of 200, 100 - 250, and 90 -125 µb/sr, respectively. To account for a near - threshold anomaly observed in the 8He spectrum the population of a 1 - continuum ( soft dipole excitation ) was considered. The lowest - energy group of events in the 10He spectrum was observed at ~ 3 MeV with a cross - section of ~ 140 µb/sr. This result is consistent with the previously reported observation of 10He providing a new g. s. position for 10He at about 3MeV. Lapshin A. E.,a Medvedev E. F.,b Polyakova I. G.,a Shepelev Y. F.a Synthesis and crystal structure of a new modification of sodium tetrahydroxyborate NaB ( OH )4 // Glass Physics and Chemistry, 2009, Volume 35, Issue 3, Pages 308 - 312 a Grebenshchikov Institute of Silicate Chemistry, Russian Academy of Sciences, nab. Makarova 2, St. Petersburg, 199034, Russian Federation A new polymorphic modification of sodium tetrahydroxyborate NaB ( OH )4 is synthesized and its crystal structure is determined. The compound crystallizes in symmetry space group P212121 with the unit cell parameters a = 5,323 ( 5 ) Г…, b = 9,496 ( 5 ) Г…, and c = 6,596 ( 5 ) Г…. The discrepancy factor for 511 symmetrically nonequivalent reflections is R = 0,0188. Layers that are formed by boron tetrahedra, aligned parallel to the ( 010 ) planes, and alternate with layers of sodium cations can be distinguished in the structure. Piskunov V. N. Parameterization of aerosol dry deposition velocities onto smooth and rough surfaces // Journal of Aerosol Science, 2009, Volume 40, Issue 8, Pages 664 - 679 RFNC - VNIIEF, Sarov, Russian Federation The velocities of aerosol deposition onto vertical and horizontal surfaces are needed for 2D and 3D calculations of aerosol transport and deposition in the urban and indoor environments. This paper analyzes the experimental results and semiempirical and theoretical models on dry deposition velocities. The features of the solution obtained by Zhao and Wu [ ( 2006 a ). Modeling particle deposition from fully developed turbulent flow in ventilation duct. Atmospheric Environment, 40, 457 - 466 ] for the velocity of aerosol deposition onto smooth surfaces are analyzed, the integrals are approximated analytically. To treat the deposition onto rough surfaces, the results of Sehmel [ ( 1973 ). Particle eddy diffusivities and deposition for isothermal flow and smooth surfaces. Journal of Aerosol Science, 4, 125 - 138 ]; Sehmel and Hodgson [ ( 1978 ). A model for predicting dry deposition of particles and gases to environmental surfaces. PNL - SA - 6721. Richland, WA: Battelle, Pacific Northwest Laboratory ] are modified and represented in a unified manner for vertical and horizontal surfaces. Cross - comparison with data of Slinn [ ( 1978 ). Parameterization for resuspension and for Wet and Dry Deposition of Particles and Gases for Use in Radiation Dose Calculations. Nucl.Safety, 19 ( 2 ), 205 - 219 ] and the model of Lai and Nazaroff [ ( 2000 ). Modeling indoor particle deposition from turbulent flow onto smooth surfaces. Journal of Aerosol Science, 31, 463 - 476 ] allowed reconciliation between the theoretical and semiempirical approaches. Finally, an approximation to the aerosol dry deposition velocities is obtained in the form of convenient parameterization formulas covering a wide range of particle sizes 0,01 µm d ≤ 1000 ≤ µm and surface roughnesses z0 ≤ 10 cm. Buiko A. M., Garanin S. F., Zmushko VV., Kalashnikov V. M., Mokhov V. N., Sokolova N. V., Yakubov V. B. On stabilization of implosion of condensed liners // Journal of Applied Mechanics and Technical Physics, 2009, Volume 50, Issue 3, Pages 361 - 370 RFNC - VNIIEF, Sarov, Russian Federation This paper considers various experimental designs on the Atlas facility to study the physics of liners and determine the optimum conditions of their stable motion. In one of the versions, in comparison with the Liner Demonstration series of experiments, in which unstable liner motion was observed, it is proposed to reduce the initial liner radius without changing its mass, which, according to two - dimensional calculations, should to lead to more stable motion of the liner with unchanged velocity. It is also proposed to perform an experiment in which periodic perturbations at a certain wavelength are created on the outer surface of the liner with a simultaneous increase in its thickness. According to calculations, the growth of chaotic perturbations is stabilized in this case with the preservation of the liner velocity. Bogdanova L. N.,a Bom V. R.,b Demin A. M.,c Demin D. L.,d Van Eijk C. W. E.,b Filchagin S. V.,c Filchenkov V. V.,d Grafov N. N.,d Grishechkin S. K.,c Gritsaj K. I.d, Konin A. D.,d Kuryakin A. V.,c Medved S. V.,d Musyaev R. K.,c Rudenko A. I.,d Tumkin D. P.,c Vinogradov Yu. I.,c Yukhimchuk A. A.,c Yukhimchuk S. A.,d Zinov V. G.,d Zlatoustovskii S. V.c Experimental investigation of muon - catalyzed t + t fusion // Journal of Experimental and Theoretical Physics, 2009, Volume 108, Issue 2, Pages 216 - 225 a State Scientific Center of Russian Federation, Institute of Theoretical and Experimental Physics, Moscow, 117218, Russian Federation The muon - catalyzed fusion ( µCF ) process in tritium was studied by the µCF collaboration on the muon beam of the JINR Phasotron. The measurements were carried out with a liquid tritium target at the temperature 22 K and density approximately 1,25 of the liquid hydrogen density ( LHD ). Parameters of the µCF cycle were determined: the ttµ muonic molecule formation rate λttµ = 2,84 ( 0,32 ) µs-1, the ttµ fusion reaction rate λf = 15,6 ( 2,0 ) µs-1, and the probability of muon sticking to helium wtt = 13,9 ( 1,5 )%. The results agree with those obtained earlier by other groups, but better accuracy was achieved due to our unique experimental method. Ogorodnikov V. A., Mikhailov A. L., Burtsev V. V., Lobastov S. A., Erunov S. V., Romanov A. V., Rudnev A. V., Kulakov E. V., Bazarov Y. B., Glushikhin V. V., Kalashnik I. A., Tsyganov V. A., Tkachenko B. I. Detecting the ejection of particles from the free surface of a shock - loaded sample // Journal of Experimental and Theoretical Physics, 2009, Volume 109, Issue 3, Pages 530 - 535 RFNC - VNIIEF, Sarov, Russian Federation The details of the ejection of 20 - to 200 - µm particles with a velocity of 1,0 - 1,5 km/s from the surfaces of lead and steel samples with a roughness of 5 - 40 µm ( Rz 5 - Rz 40 ) when shock waves with an amplitude of 15 and 27 GPa reach them are visualized with a high - speed streak camera with a CCD matrix and pulsed laser illumination at a pulse duration of 4 ns. The size and velocity distributions of the particles are obtained. Vinogradov A.,a Mozgovoi A.,b Lazarev S.,b Gornostai - Polskii S.,b Okumura R.,c Hashimoto S.a Nanostructure formation in the surface layer of metals under influence of high - power electric current pulse // Journal of Materials Science, 2009, Volume 44, Issue 17, Pages 4546 - 4552 a Osaka City University, Osaka 558 - 8585, Japan The possibility to tailor the microstructure of metals is explored utilising a skin - effect for surface treatment. The theoretical simulation of the electric and magnetic fields in a metallic cylinder shows that melting followed by rapid quenching can occur in a skin layer of 5 - 10 µm thickness if the amplitude of a single electric pulse of several nanoseconds duration is of the order of hundreds kiloamperes. The experiments using the SUS304 stainless steel show that besides a thin amorphous layer, a specific nano-twin structure can form at the near - surface region. The appearance of nano - twins is explained considering the stress components arising at the surface layer and in the bulk of the specimen during shock wave propagation caused by temperature gradients and the Lorentz force. It is shown that the high stress amplitudes can arise locally, furnishing the required conditions for twin nucleation and resulting in intensive plastic deformation of the sub - surface layer.
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