Low-frequency dielectric dispersion and pyroelectric effect in ferroelectric vinylidene fluoride-trifluoroethylene copolymer in phase transitions
Low-frequency dielectric dispersion and pyroelectric effect in ferroelectric vinylidene fluoride-trifluoroethylene copolymer in phase transitions
K.A. Verkhovskaya, N.D. Gavrilova, V.K. Novik, I.A. Malyshkina, T.B. Frolova
The investigations of the dielectric constant, the pyroelectric coefficient and thermodepolarization currents both of a pure and a rhodamine-doped copolymer of vinylidene fluoride with trifluoroethylene (P(VF-TFE)) (70/30) have been carried out over a wide range of frequencies and temperatures. The temperature relationships obtained experimentally point to the reorganization of the structure of the amorphous phase of pure (P(VF-TFE)) in the temperature range of 313-323 K. The effect of doping on the specific feature of the copolymer has been studied.
Show AbstractEffect of crystallite size on optical spectra of diamond powders and polycrystalline films
Effect of crystallite size on optical spectra of diamond powders and polycrystalline films
A.N. Obraztsov$^1$, T. Izumi$^2$, H. Okushi$^3$, H. Watanabe$^3$, I.Yu. Pavlovsky$^1$
The present work submits the results of an investigation of diamond polycrystalline films, synthetic diamond powders and single crystals. Using photoacoustic spectroscopy, it was found that in the optical absorption spectra of all the three types of diamond materials studied there is a band corresponding to inter band absorption for quanta with energy exceeding 5.5 eV. For single-crystal samples an absorption band due to nitrogen impurities was detected and for polycrystalline films and powders there was observed a broad band due to structural defects. The specific feature of the spectra of films and powders is a strong light scattering in the ultraviolet region (250-300 nm), the efficiency of which increased with decrease of crystallite size from $\sim$100 to $\sim$1 μm. Further decrease of the size of diamond particles (down to 0.25 μm and less) diminished the share of scattered light because of the change of particles faceting and their coalescence.
Show AbstractEffect of water mass aeration on vertical temperature distribution in the near-the-water layer of the atmosphere
Effect of water mass aeration on vertical temperature distribution in the near-the-water layer of the atmosphere
E.P. Anisimova, S.N. Dikarev, A.A. Speranskaya, O.A. Speranskaya
Experimental data on the vertical temperature distribution in a thin near-thewater air layer over aerated and nonaerated water have been reported. The heat flux from aerated water into the atmosphere, other conditions being equal, is higher than that from nonaerated water.
Show AbstractEffect of water surface pollution by petroleum products on the formation of Langmuir circulations and the energy exchange between a basin and the atmosphere
Effect of water surface pollution by petroleum products on the formation of Langmuir circulations and the energy exchange between a basin and the atmosphere
N.S. Blokhina, A.E. Ordanovich
A novel mathematical model is used for investigating the effect of oil pollutions on the characteristics of Langmuir circulations and the streams of sensitive and latent heat from a basin into the atmosphere. Calculations have been performed for a wide range of wind velocities over the basin and for the values of Dalton's number which depends on the surface pollution. A range of parameters in which the Langmuir circulations disappear has been found. Estimates have been made of the temperature differences between the water surface and the air, as well as between the water surface and the bottom, as functions of wind velocity and Dalton's number.
Show AbstractExperimental investigations of spatial structure of traveling ionospheric disturbances
Experimental investigations of spatial structure of traveling ionospheric disturbances
V.D. Gusev, A.G. Vologdin, D.V. Kiryanov
A methodology is proposed for the solution of the inverse problem associated with experimental investigation of traveling ionospheric disturbances on oblique-incidence radiosonde observation on the ground.
Show AbstractOn the kink in the energy spectrum of cosmic rays
On the kink in the energy spectrum of cosmic rays
N.F. Gorshkov
On the assumption that the motion of charged particles in cosmic rays (CR) is mainly determined by diffusion and the Lorentz force, estimates have been derived which show that the well-known kink in the CR energy spectrum at the energy $Е = З\cdot 10^{15}$ eV is due to a change in the character of turbulent motion in interstellar medium regions with nonuniform magnetic fields, whose scale is comparable with the thickness of the galactic disk. The application of the theories of similarity and dimensionality allowed us to describe qualitatively the experimentally observed CR energy spectrum in the kink's vicinity over the energy range of CR particles amounting to four orders of magnitude.
Show AbstractRadiative shift of neutrino energy in a magnetized electron-positron gas
Radiative shift of neutrino energy in a magnetized electron-positron gas
P.A. Eminov, V.Yu. Grishina
A radiative energy shift and an induced magnetic moment of a relativistic massive Dirac neutrino in a hot electron-positron plasma and in a degenerate electron gas in an external unquantizing magnetic field have been calculated.
Show AbstractApproximate calculation of Green's function for the Poisson equation on space $E _{D-2}\times V_2$
Approximate calculation of Green's function for the Poisson equation on space $E _{D-2}\times V_2$
Yu.V. Grats, A.B. Lavrent'ev
The feasibility of approximately calculating the Green function for the Poisson equation on the space $E _{D-2}\times V_2$ and its regularized value in the limit of coinciding points is studied.
Show AbstractStill parametric solitons in periodically nonuniform media with quadratic nonlinearity
Still parametric solitons in periodically nonuniform media with quadratic nonlinearity
S.V. Polyakov, A.P. Sukhorukov
Equations have been derived for the envelopes of still parametric solitons at the fundamental and double frequencies in periodically nonuniform media. The integrals of motion have been obtained and the exact solution which describes the spatial distribution of vibrations has been found. The conditions of formation and the properties of still solitons have been analyzed.
Show AbstractHydrogen-induced nonequilibrium oscillating phase transitions in solid-state open Pd-Sm-H systems and Belousov-Zhabotinskii waves
Hydrogen-induced nonequilibrium oscillating phase transitions in solid-state open Pd-Sm-H systems and Belousov-Zhabotinskii waves
A.A. Katsnel'son, G.P. Revkevich, V.M. Avdyukhina
New phenomena in nonequilibrium open Pd-Sm-H systems have been observed: as a result of saturation with hydrogen followed by degassing, a one-phase system transforms into a two-phase one, and the two-phase system, into the one-phase one. This indicates the occurrence of nonequilibrium oscillating phase transitions. According to the hypothesis suggested by the authors, the observed phenomena are explained by competition between ascending and gradient diffusion under substantially nonequilibrium conditions of the open solid-state system.
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