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71.
Usychenko A. S. Usychenko V. G. Sorokin L. N. 《Radiophysics and Quantum Electronics》2021,64(1):54-63
Radiophysics and Quantum Electronics - It has been proved by computer simulation methods that for given antenna parameters, three parts of energy of ultrashort electromagnetic pulses, namely,... 相似文献
72.
Amirov V. Kh. Gorbovskiy A. I. Davydenko V. I. Deychuli P. P. Ivanov A. A. Kapitonov V. A. Mishagin V. V. Sorokin A. V. Shikhovtsev I. V. 《Physics of Atomic Nuclei》2021,84(7):1285-1290
Physics of Atomic Nuclei - To heat the plasma in the TCV tokamak (Lausanne, Switzerland), a charge exchange injector of a focused beam of fast deuterium atoms with an energy of 30 keV, a power of 1... 相似文献
73.
A. A. Sorokin V. P. Gar’kin N. S. Red’kin A. K. Buryak 《Russian Journal of Applied Chemistry》2010,83(12):2163-2167
Various types of ionization of organotellurium compounds in mass-spectrometric study are considered, with diphenyl telluroxide
as example. The mass spectra of diphenyl telluroxide are presented. The possibility of applying surface-activated and matrix-assisted
laser desorption/ionization mass spectrometry to organotellurium compounds is examined. 相似文献
74.
A. O. Sorokin A. V. Syromyatnikov 《Journal of Experimental and Theoretical Physics》2011,113(4):673-677
Two models of classic XY antiferromagnets in three dimensions are studied by Monte Carlo simulation: the model on a simple
cubic lattice with two extra intralayer exchanges and the model on a stackedtriangular lattice with an extra interlayer exchange.
In suggested models, the order parameters are magnetization and two chiral parameters. A transition corresponds to breaking
ℤ2 ⊗ ℤ2 ⊗ SO(2) symmetry. A distinct first order transition is found in both models. 相似文献
75.
S. B. Sorokin 《Numerical Analysis and Applications》2011,4(2):167-174
An iterative algorithm for the numerical solution of the biharmonic equation with boundary conditions of the first kind (a clamped plate) is investigated. At every step of this iterative method, it is necessary to solve two Dirichlet problems for a Poisson equation. Constants of energy equivalence for the optimization of the iterative method are obtained. 相似文献
76.
S. A. Sorokin 《Technical Physics》2011,56(7):957-962
Experimental data for creating an X-ray source several millimeters in size on the basis of a plasmafilled rod-pinch diode are reported. Experiments are carried out on the MIG high-current generator. A voltage pulse applied to the diode is sharpened and shortened by injecting plasma into the interelectrode gap up to the plasma-filled diode. Radiation extraction from the vacuum chamber in the paraxial direction is provided by inverting the positions of the cathode and anode using a post-hole vacuum convolute. It is demonstrated that the energy of a low-impedance high-current generator can be deposited with a high efficiency into an electron beam focused on the 1-mm2 tip of the rod-shaped anode. With a tapered tungsten rod 1.5 mm in diameter used as an anode, a pulsed X-ray source about 1 mm in size generating 30-ns-long pulses is obtained. The absorbed dose per pulse measured with a LiF thermoluminescent dosimeter behind a 5-mm-thick aluminum screen 1 m away from the source reaches 0.042 Gy. 相似文献
77.
78.
For a thin ferromagnetic film, the braking process of a 180° domain boundary in a field of randomly distributed point defects
is studied using perturbation theory. It is established that, for low velocities, the motion of the boundary is nonsteady-state.
It is shown that the critical velocity of steady-state motion depends substantially on film thickness and the defect concentration.
Fiz. Tverd. Tela (St. Petersburg) 41, 1231–1235 (July 1999) 相似文献
79.
V. V. Bel’kov Yu. V. Zhilyaev G. N. Mosina S. D. Raevskii L. M. Sorokin M. P. Shcheglov 《Physics of the Solid State》2000,42(9):1606-1609
The structure of bulk GaN layers grown on (0001) sapphire substrates by vapor-phase epitaxy has been studied by x-ray diffraction and transmission electron microscopy (TEM). It is found that these layers contain grown-in and screw dislocations. The dislocation density decreases away from the interface. The effect of an amorphous buffer layer on the formation of the initial GaN layer and, thus, on the degree of perfection of gallium nitride layers is elucidated. A model of generating grown-in dislocations and the relaxation mechanism of misfit stresses are proposed. 相似文献
80.
Self-injection length in La0.7Ca0.3MnO3-YBa2Cu3O7-δ ferromagnet-superconductor multilayer thin films
We have carried out extensive studies on the self-injection problem in barrierless heterojunctions between La0.7Ca0.3MnO3 (LCMO) and YBa2Cu3O7-δ (YBCO) thin films. The heterojunctions were formed in situ by sequentially growing LCMO and YBCO films on 〈100〉 LaAlO3 (LAO) substrate using a pulsed laser deposition (PLD) system. YBCO micro-bridges with 64 μm width were patterned both on
the LAO (control) and LCMO side of the substrate. Critical current, I
c, was measured at 77 K on both the control side as well as the LCMO side for different YBCO film thickness. It was observed
that while the control side showed a J
c of ∼ 2 × 106 A/cm2, the LCMO side showed about half the value for the same thickness (1800 ?). The difference in J
c indicates that a certain thickness of YBCO has become ‘effectively’ normal due to self-injection. From the measurement of
J
c at two different thicknesses (1800 ? and 1500 ?) of YBCO films both on the LAO as well as the LCMO side, the value of self-injection
length (at 77 K) was estimated to be ∼ 900 ?. To the authors’ best knowledge, this is the first time that self-injection length
has been quantified. A control experiment carried out with LaNiO3 deposited by PLD on YBCO did not show any evidence of self-injection. 相似文献