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111.
Yu. B. Golubovskii V. O. Nekuchaev N. S. Ponomarev I. A. Porokhova 《Technical Physics》1997,42(9):997-1003
Numerous papers have been devoted to the investigation of striations in inert gases at low pressures (p⩽2 Torr) and small currents (i<100 mA) [A. V. Nedospasov, Sov. Phys. Usp. 11, 174 (1968); L. Pekarek, Sov. Phys. Usp. 11, 188 (1968); N. L. Oleson and A. W. Cooper, Adv. Electron. Electron Phys. 24, 155 (1968); P. S. Landa, N. A. Miskinova, and Yu. V. Ponomarev, Sov. Phys. Usp. 23, 813 (1980)]. Since the nature of striations is determined under these conditions by the nonlocal kinetics of the electrons
in spatially periodic fields [L. D. Tsendin, Sov. J. Plasma Phys. 8, 228 (1982)], an investigation of the electron distribution function in space and time would be very interesting. The purpose
of the present work is to experimentally investigate the potential profiles and distribution functions in S and P striations and to analyze the mechanism which shapes the distribution functions for striations of these types.
Zh. Tekh. Fiz. 67, 14–21 (September 1997) 相似文献
112.
A. N. Brozdnichenko A. N. Ponomarev V. P. Pronin V. V. Rybalko 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2007,1(1):110-112
The force interaction between anode and cathode in the process of field-emission current extraction from cathodes based on carbon nanoclusters—carbon nanotubes and astralenes—has been investigated. The measured forces are linear functions of the field-emission current and significantly exceed the forces conditioned by the electrostatic nature of interaction. The observed effect is explained within the framework of a model that suggests the formation of magnetic nanoclusters in the cathode and the emission of polarized electrons. 相似文献
113.
V. A. Rebrov A. G. Ponomarev D. V. Magilin I. A. Beloshapka A. B. Dudnik S. N. Abramovich N. V. Zavjalov A. G. Zvenigorodsky E. V. Zimin 《Technical Physics》2007,52(3):365-368
Basic ideas underlying the design of a precision magnetic quadrupole lens for a nuclear scanning microprobe with a maximal accelerating voltage of 14 MV are set forth. Four magnetic quadrupoles are combined into doublets. The doublets are placed on adjusting gears, which bring the local coordinate system of each lens into coincidence with the laboratory system related to the axis of the beam. Each lens provides a maximal gradient of the field of 0.68 T/cm, which makes it possible to perform stigmatic focusing of the beam with a working distance of 22 cm. All lenses are nonseparable and made of one piece of high-quality electrical steel. A special lens-feeding unit is designed that provides manual and remote control of pole tip excitation. 相似文献
114.
L. P. Shadrina Yu. P. Dormidontov V. G. Ponomarev I. I. Lapkin 《Chemistry of Heterocyclic Compounds》1987,23(9):964-967
The reactions of organomagnesium derivatives of 2-methyl- or 2,3-dimethyl-7-azaindoles and 2,3-dimethylbenz[4,5]- or -[6,7]indoles with diethyl oxalate, and the reactivity of the resulting ethoxalylindoles towards phenylmagnesium bromide, have been examined. It has been shown that the course of the reaction is dependent on the solvent and the structures of the starting materials.No footnote given in Russian original — Publisher.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1206–1209, September, 1987. 相似文献
115.
V. G. Grebinnik V. N. Duginov V. A. Zhukov S. Kapusta A. B. Lazarev V. G. Olshevsky V. Y. Pomjakushin S. N. Shilov I. I. Gurevich B. F. Kirillov B. A. Nikolsky A. V. Pirogov A. N. Ponomarev V. A. Suetin I. P. Borovinskaya M. D. Nersesyan A. G. Persada Y. F. Eltzev V. R. Kapasik O. E. Omelyanovski 《Hyperfine Interactions》1990,61(1-4):1085-1088
116.
I.V. Ponomarev L.I. Deych V.A. Shuvayev A.A. Lisyansky 《Physica E: Low-dimensional Systems and Nanostructures》2005,25(4):539-553
We introduce a computationally efficient approach to calculating characteristics of excitons in quantum wells. In this approach we derive a system of self-consistent equations describing the motion of an electron–hole pair. The motion in the growth direction of the quantum well in this approach is separated from the in-plane motion, but each of them occurs in modified potentials found self-consistently. The approach is applied to shallow quantum wells, for which we obtained an analytical expression for the exciton binding energy and the ground state eigenfunction. Our numerical results yield lower exciton binding energies in comparison to standard variational calculations, while require reduced computational effort. 相似文献
117.
Scheibner M Ponomarev IV Stinaff EA Doty MF Bracker AS Hellberg CS Reinecke TL Gammon D 《Physical review letters》2007,99(19):197402
We present photoluminescence studies of the molecular neutral biexciton-exciton spectra of individual vertically stacked InAs/GaAs quantum dot pairs. We tune either the hole or the electron levels of the two dots into tunneling resonances. The spectra are described well within a few-level, few-particle molecular model. Their properties can be modified broadly by an electric field and by structural design, which makes them highly attractive for controlling nonlinear optical properties. 相似文献
118.
A. N. Ponomarev E. F. Abdrashitov D. A. Kritskaya V. Ch. Bokun E. A. Sanginov Yu. A. Dobrovol’skii 《Russian Journal of Electrochemistry》2017,53(6):589-607
Methods for the preparation of composite ion-exchange membranes from polymer (polyvinylidene fluoride (PVDF), ultrahigh molecular weight polyethylene (UHMWPE), and polypropylene (PP)) matrices were considered. Polystyrene (PS) was introduced in the matrices by thermal polymerization of the monomer followed by sulfonation of the implant. The fundamentals of membrane synthesis from industrial polytetrafluoroethylene (PTFE, Teflon F-4) films by thermal polymerization of styrene in a film stretched in a monomer solution followed by sulfonation of incorporated PS were described. The literature on radiation- chemical synthesis of composite ion-exchange membranes based on polymer matrices with embedded polystyrene and its subsequent sulfonation was analyzed. Some problems of the kinetics and mechanism of thermal implantation of PS into various polymer matrices under different conditions were discussed. The physicochemical characteristics, structure, and transport properties of the membranes synthesized by thermal implantation of PS were reported. The obtained membranes were tested in low-temperature fuel cells. 相似文献
119.
120.
E. F. Abdrashitov D. A. Kritskaya V. Ch. Bokun A. N. Ponomarev 《High Energy Chemistry》2014,48(5):353-357
A method has been developed for modifying the surface layer of polytetrafluoroethylene by incorporation of poly(vinylidene chloride) via UV radiation-initiated graft polymerization of vinylidene chloride from the vapor phase using a PRK-4 mercury lamp. By the subsequent treatment of the composition with aqueous ammonia, dehydrochlorination (carbonization) of the grafted poly(vinylidene chloride) has been performed. The kinetics of UV grafting and the distribution of the carbonized phase in the polytetrafluoroethylene matrix have been studied. A material with the carbonized surface layer of a 10—30 μm thickness and a contact angle of about 57° remaining stable over time has been obtained. 相似文献