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561.
Homogeneous nucleation at high supersaturation of vapor and heterogeneous nucleation on microscopic wettable particles are studied on the basis of Lennard-Jones model system. A hybrid classical thermodynamics and density-functional theory (DFT) approach is undertaken to treat the nucleation problems. Local-density approximation and weighted-density approximation are employed within the framework of DFT. Special attention is given to the disjoining pressure of small liquid droplets, which is dependent on the thickness of wetting film and radius of the wettable particle. Different contributions to the disjoining pressure are examined using both analytical estimations and numerical DFT calculation. It is shown that van der Waals interaction results in negative contribution to the disjoining pressure. The presence of wettable particles results in positive contribution to the disjoining pressure, which plays the key role in the heterogeneous nucleation. Several definitions of the surface tension of liquid droplets are discussed. Curvature dependence of the surface tension of small liquid droplets is computed. The important characteristics of nucleation, including the formation free energy of the droplet and nucleation barrier height, are obtained. 相似文献
562.
A. M. Bykov S. M. Osipov D. Ellison 《Bulletin of the Russian Academy of Sciences: Physics》2017,81(4):431-433
A nonlinear model of particle spectra and nonadiabatic magnetic field amplification in supernova shells is presented. The effect super-diffusive particle propagation in the vicinity of a shock wave has on the spectra of accelerated particles and magnetic field fluctuations is studied in a Monte Carlo simulation. 相似文献
563.
S. I. Belov G. V. Boriskov A. I. Bykov M. I. Dolotenko N. I. Egorov A. S. Korshunov Yu. B. Kudasov I. V. Makarov V. D. Selemir A. V. Filippov 《JETP Letters》2017,105(3):195-199
The relative permittivity and specific conductivity of water and ice are measured under isentropic compression to pressures above 300 GPa. Compression is initiated by a pulse of an ultrahigh magnetic field generated by an MK-1 magnetocumulative generator. The sample is placed in a coaxial compression chamber with an initial volume of about 40 cm3. The complex relative permittivity was measured by a fast-response reflectometer at a frequency of about 50 MHz. At the compression of water, its relative permittivity increases to ε = 350 at a pressure of 8 GPa, then drops sharply to ε = 140, and further decreases smoothly. It is shown that measurements of the relative permittivity under isentropic compression make it possible to determine interfaces between ordered and disordered phases of water and ice, as well as to reveal features associated with a change in the activation energy of defects. 相似文献
564.
565.
R. F. Trunin G. V. Boriskov A. I. Bykov R. I. Il’kaev G. V. Simakov V. D. Urlin A. N. Shuĭkin 《Technical Physics》2006,51(7):907-918
Experiments on shock wave compression of solid hydrogen (protium) up to 66 GPa and deuterium (in the initially liquid or solid phase) up to 123 GPa using spherical devices where a steel ball (impactor) is explosion-accelerated to 23 km/s are described. The experimental data are compared with those obtained by American researchers for liquid deuterium and protium, who used conventional explosives and light-gas guns as energy sources in the experiments carried out on the Z machine at Sandia National Labs, where an impactor was accelerated by an ultrahigh magnetic field, or on the NOVA laser at the Livermore National laboratory. Our data agree well with those derived by Sandia Labs. 相似文献
566.
567.
568.
A. A. Bykov D. V. Nomokonov A. K. Bakarov A. V. Goran O. Estibals J. C. Portal 《JETP Letters》2004,79(1):28-31
The Aharonov-Bohm effect in submicron rings with narrow electron channels was studied in the range of magnetic fields from 0 to 15 T and temperatures from 0.1 to 10 K. It is found that the temperature dependences of the h/e-oscillation amplitude at low magnetic fields and in the situation of tunnel-coupled edge current states are different. The obtained experimental data are explained by the influence of Fermi-system chirality on the coherent transport in a ring interferometer. 相似文献
569.
A. Granovskii V. Gushchin I. Bykov A. Kozlov N. Kobayashi S. Ohnuma T. Masumoto M. Inoue 《Physics of the Solid State》2003,45(5):911-913
This paper reports on an IR study (5–20 µm) of the dispersion and field dependences of the magnetorefractive effect in granular CoFe-MgF (metal-insulator) systems, which exhibit, in compositions close to the percolation threshold, a tunneling magnetoresistance of 7.5% in a field of 1700 Oe. The change in the reflectivity of p-polarized light under magnetization in the IR spectral region 5–7 µm is of the order of 0.1%, while in the 10-to 12-µm region, this change, reaches record-high values of 1.2–1.5%, which exceed the usual odd and even magnetooptic reflectivities in the IR range by two orders of magnitude. The magnetorefractive effect in magnetic systems with tunneling conduction originates from spin-dependent high-frequency tunneling. 相似文献
570.
Summary A new flavonoid glycoside, 3--D-glucopyranosyloxy-4,5,7-trihydroxy-8-methoxyflavone has been isolated from the flowers of Crataegus pinnatifida.Khabarovsk State Medical Institute. All-Union Scientific-Research Institute of Medicinal Plants. Translated from Khimiya Priodnykh Soedinenii, No. 6, pp. 715–718, November–December, 1972. 相似文献