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91.
V. E. Fortov A. P. Nefedov O. S. Vaulina A. M. Lipaev V. I. Molotkov A. A. Samaryan V. P. Nikitskii A. I. Ivanov S. F. Savin A. V. Kalmykov A. Ya. Solov’ev P. V. Vinogradov 《Journal of Experimental and Theoretical Physics》1998,87(6):1087-1097
The dynamics of the formation of ordered structures of macroparticles charged by photoemission under the action of solar radiation
under microgravitational conditions without the use of electrostatic traps to confine the particles is studied experimentally
and theoretically. The working conditions needed for the formation of structures of charged macroparticles are chosen as a
result of a numerical solution of the problem posed, the particle charges and the interparticle interaction parameter are
determined, and the characteristic times specifying the dynamics of the formation of an ordered system of macroparticles are
calculated. The behavior of an ensemble of macroparticles under the effect of solar radiation is observed experimentally on
board the Mir space station. An analysis and comparison of the results of the experimental and theoretical investigations
permit drawing a conclusion regarding the possibility of the existences of extended ordered formations of macroparticles charged
by photoemission under microgravitational conditions.
Zh. éksp. Teor. Fiz. 114, 2004–2021 (December 1998) 相似文献
92.
93.
B. A. Cheskis N. M. Ivanova A. M. Moiseenkov O. M. Nefedov 《Russian Chemical Bulletin》1990,39(11):2296-2300
The zinc halide-initiated homoallylic rearrangement of saturated or allylic cyclopropylcarbinols in the presence of trimethylsilyl halides has been employed as the key step in the total synthesis of seven behavioral regulators in twenty insects of theLepidoptera family, namely 9E-tetradecenol and its acetate, 11E-hexadecenol and its acetate, 11E-hexadecenal, 5E, 7E-dodecadienol, and 3E, 5E-tetradecadienyl acetate.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2539–2544, November, 1990. 相似文献
94.
V. G. Kiptilyi A. V. Livke V. I. Nagornyi Yu. Ya. Nefedov M. V. Savin V. I. Semenov V. A. Chirkin 《Technical Physics》1998,43(4):471-472
The quality of suppression of neutrons by lithium hydride 6LiH filters for narrow and wide beams from a neutron generator incorporating deuterium and tritium targets is investigated.
The experimental data can be used for the design of measurement apparatus operating in high neutron fields.
Zh. Tekh. Fiz. 68, 136–138 (April 1998) 相似文献
95.
96.
A. P. Nefedov O. S. Vaulina O. F. Petrov V. I. Molotkov V. M. Torchinskii V. E. Fortov A. V. Chernyshev A. M. Lipaev A. I. Ivanov A. Yu. Kaleri Yu. P. Semenov S. V. Zaletin 《Journal of Experimental and Theoretical Physics》2002,95(4):673-681
The dynamics of large-sized (70-180 μm) spherical bronze particles in a direct current glow discharge plasma was studied experimentally under microgravitation conditions. The temperatures, velocities, pair correlation functions, and self-diffusion coefficients of macroparticles were measured at various discharge currents. The charges of dust particles (on the order of 106 e) corresponded to high surface potentials of about 30–40 V. The experimental data were in close agreement with the simulation data on Yukawa systems with weak screening of dust charges. The influence of macroparticles on equilibrium ionization in a dense dust cloud was considered. 相似文献
97.
A method of classification of many-electron states that involves symmetry groups of four-dimensional space is developed. Taking into account the spatial and temporal symmetry, the selection rules for electric and magnetic dipole transitions are investigated. The reduction relations for the irreducible representations of the orthogonal group O 4 and the group R 4 of pure rotations of the four-dimensional space on the groups and O h 4 and O 4 of the four-dimensional cube and of the octahedron on the three-dimensional groups O h and D 6h of the cubic and hexagonal systems, respectively, are obtained. The four-dimensional classification of the levels of the spin-orbit interaction of rare earth ions for the intermediate reduction on the group of the four-dimensional cube is performed. With the help of the irreducible representations of the O 4 group, the selection rules of magnetic and forbidden electric dipole transitions, as well as of intercombination transitions, are investigated. 相似文献
98.
N. V. Cherkashina S. E. Nefedov M. A. Uvarova A. P. Klyagina A. A. Markov M. N. Vargaftik I. I. Moiseev 《Russian Journal of Inorganic Chemistry》2014,59(5):446-454
New carboxylate platinum(II) complexes: syn and anti isomers of Pt(phen)(OOCMe)2 molecular complex, [Pt(phen)(NCMe)2](O3SCF3)2, as well as unusual sandwich complex [Pt(phen)2]2+ · 2syn-[Pt(phen)(OOCMe)2] where [Pt(phen)2]2+ cation is inserted between two syn-Pt(phen)(OOCMe)2 molecules were synthesized and structurally characterized by X-ray diffraction analysis. As distinct from syn- and anti-Pt(phen)(OOCMe)2 and [Pt(phen)(NCMe)2](O3SCF3)2 complexes with flat phenanthroline ligand, the phen ligands in [Pt(phen)2]2+ cation have a curved configuration. Comparative DFT analysis of geometry of model structures phen, phen+, phenH+, and [Ptphen2] n+ (n = 1, 2) showed that electron removal from phen molecule had no effect on its geometry in both free state and platinum(II) complexes. 相似文献
99.
E. Ya. Misochko A. V. Akimov A. A. Masitov D. V. Korchagin S. M. Aldoshin S. E. Boganov K. N. Shavrin V. D. Gvozdev M. P. Egorov O. M. Nefedov 《Russian Chemical Bulletin》2011,60(11):2180-2187
The ESR spectrum of the first representative of highly conjugated triplet ethynylvinylcarbenes, 5-methylhexa-1,2,4-triene-1,3-diyl (1), was recorded in solid argon matrix. The zero-field splitting (ZFS) parameters of carbene 1 (D = 0.5054±0.0006 cm?1 and E = 0.0045±0.0002 cm?1) determined from the experimental ESR spectrum are in between the corresponding parameters of ethynylcarbene C3H2 (2) and vinylcarbene C3H4 (3): D(3) < D(1) < D(2) and E(2) < E(1) < E(3). Quantum chemical calculations of the ZFS parameters of 1, 2, and 3 have been carried out for the first time using two DFT-based approaches, RODFT and UDFT. An analysis of the experimental and theoretical ZFS parameters shows that carbene 1 is characterized by a greater extent of delocalization of the spin density of unpaired electrons than carbenes 2 and 3. The characteristic structural fragments of carbene 1 possess the principal features of the electronic structure of both ethynylcarbene (2) and vinylcarbene (3), respectively. Magnetic spin-spin interactions are identical in carbenes 1 and 2. The dominant contribution to D in 1 and 2 results from the one-center spin-spin interactions on carbon atoms in the propynylidene group, which are subjected to strong spin polarization. 相似文献
100.
N. N. Nefedov A. G. Nikitin 《Computational Mathematics and Mathematical Physics》2011,51(6):1011-1019
A nonlinear parabolic integral problem arising in dynamic simulation of processes in activator-inhibitor systems is considered.
Based on the asymptotic theory of such problems previously developed by the authors, the existence of solutions with boundary
and internal layers is proved and their asymptotic behavior is found. 相似文献