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11.
Yu. G. Abov A. D. Gul'ko F. S. Dzheparov S. V. Stepanov S. S. Trostin 《Physics of Atomic Nuclei》2002,65(11):1999-2008
The nuclear magnetic resonance in beta-active nuclei 8Li at the doubled Larmor frequency in LiF polycrystals is studied before and after treating these polycrystals with an external pressure. A quantitative approach is proposed that makes it possible to calculate the parameters of the resonance line-shape function versus the dislocation structure of crystallites. Data suggesting that the samples under investigation that were subjected to a treatment with an external pressure develop dislocations whose Burgers vectors are parallel are obtained. 相似文献
12.
13.
V. N. Esenin A. A. Stepanov L. I. Denisovich 《Russian Journal of Applied Chemistry》2006,79(12):1957-1963
Electrochemical procedure for express evaluation of the corrosion effect of aqueous glycol solutions on the metallic construction materials for cooling systems was studied. This procedure was used to develop new coolant formulations. 相似文献
14.
Ion synthesis and laser annealing of Cu nanoparticles in Al2O3 总被引:1,自引:0,他引:1
A.L. Stepanov V.N. Popok D.E. Hole I.B. Khaibullin 《Applied Physics A: Materials Science & Processing》2002,74(3):441-446
Al2O3 samples with Cu nanoparticles, synthesised by ion implantation at 40 keV with a dose of 1×1017 ion/cm2 and a current density from 2.5 to 12.5 μA/cm2, were annealed using ten pulses from a KrF excimer laser with a single pulse fluence of 0.3 J/cm2. The copper depth distribution, formation and modification of metal nanoparticles under the ion implantation and laser treatment
were studied by Rutherford backscattering (RBS), energy dispersive X-ray (EDX) analysis, atomic force microscopy (AFM) and
optical spectroscopy. It was found that laser annealing leads to a reduction in the nanoparticle size without diffusion of
metal atoms into the bulk. The change in particle size and the possibility for oxidation of the copper particles are examined
in the framework of Mie theory. Calculations presented show that under excimer laser treatment, Cu nanoparticles are more
likely to be reduced in size than to undergo oxidation.
Received: 19 April 2001 / Accepted: 7 November 2001 / Published online: 23 January 2002 相似文献
15.
The internal conical refraction of a Bessel beam of arbitrary order is studied theoretically. It is shown that a beam of the order m of arbitrary polarization in the general case is partially converted to Bessel beams of the order m ± 1 with orthogonal circular polarizations. Conditions for complete conversion of a beam of the order m to a Bessel beam of the order m?1 or m+1 are determined. 相似文献
16.
Alexander G. Stepanov Sergei S. Arzumanov Horst Ernst Dieter Freude 《Chemical physics letters》2006,420(4-6):574-576
It has been demonstrated that 1H MAS NMR spectroscopy can be used as a tool for in situ monitoring the reaction kinetics of 13C-labeled carbon scrambling in alkane molecules adsorbed on zeolite catalysts at the reaction temperature of 540–570 K. The accuracy of the results and the time resolution are improved compared to 13C MAS NMR spectroscopy. 相似文献
17.
18.
L. A. Oparina O. V. Vysotskaya A. V. Stepanov I. V. Rodionova G. F. Myachina N. K. Gusarova B. A. Trofimov 《Russian Journal of Organic Chemistry》2008,44(1):120-123
2-Hydroxymethylfuran reacted with acetylene in superbasic catalytic systems MOH-DMSO (M = Na, K) under mild temperature conditions (75–85°C, 1–2 h), yielding 80% of 2-vinyloxymethylfuran. The product, as well as acetaldehyde acetals derived therefrom, turned out to be promising as modifiers for electrolyte in lithium-sulfur rechargeable batteries. 相似文献
19.
We construct a strong Laplacian D * D by using the third operator in the basis {d,d *,D} of the space of natural first-order operators acting on the differential forms of a Riemannian manifold (M,g). We study the properties of the Laplacian D * D and obtain Weitzenbock's formula relating the three strong Laplacians dd *, d * d, and D * D to the curvature of the manifold (M,g). 相似文献
20.
S. B. Sakuta B. G. Novatsky D. N. Stepanov D. V. Aleksandrov Yu. A. Glukhov E. Yu. Nikol'sky 《Physics of Atomic Nuclei》2002,65(10):1771-1777
The (6Li, 7Be) and (6Li, 7Li) reactions on 6Li and 7Li nuclei were investigated in the angular interval 0°–20° in the laboratory system at a 6Li energy of 93 MeV. In addition to low-lying states of the 5,6He and 5,6Li nuclei, broad structures were observed near the t(3He)+d and t(3He)+t thresholds at the excitation energies of 16.75 (3/2+) and ~20 MeV (for 5He), 16.66 (3/2+) and ~20 MeV (5Li), 14.0 and 25 MeV (6He), and ~20 MeV (6Li). The angular distributions measured in the 7Li(6Li, 7Be)6He reaction for transitions to the ground state (0+) and excited states at E x=1.8 MeV (2+) and 14.0 MeV of the 6He nucleus were analyzed by the finite-range distorted-wave method assuming the 1p-and 1s-proton pickup mechanism. The (6Li, 7Be) and (6Li, 7Li) reactions were shown to proceed predominantly through the one-step pickup mechanism, and the broad structures observed at high excitation energies are considered as quasimolecular states of the t(3He)+d and t(3He)+t types. 相似文献