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21.
M. V. Zagidullin V. D. Nikolaev M. I. Svistun N. A. Khvatov E. V. Fomin 《Optics and Spectroscopy》2008,105(2):202-207
The concentrations of water vapor and O2(1Δ), as well as the temperature in the gas flow at the exit of a singlet oxygen generator, are determined using multichannel recording of the singlet oxygen emission spectrum in the bands at 634, 703, 762, and 1268 nm. The water vapor concentration is found from the intensity ratio of the 762-nm band, which corresponds to the 1Σ → 3Σ transition of the oxygen molecule, and the dimole emission band at 634 nm. From the ratio of the integrated intensities of the bands at 634 and 1268 nm, the O2(1Δ) concentration is determined and it is shown that the yield of O2(1Δ) at the exit from the gas generator is about 52%. The temperature of the gas flow, determined by the rotational structure of the oxygen emission spectrum in the band at 762 nm, is about 300 K under the nominal conditions of the gas generator operation. The ratio of the photon fluxes in the 703 and 634nm bands of the O2(1Δ) dimole emission is 1.06. The temperature dependence of the dimole emission bandwidths is determined, which can be used for estimating the gas temperature at the exit of the O2(1Δ) generator. 相似文献
22.
V. N. Zinovyev I. V. Kazanin V. A. Lebiga A. Yu. Pak A. S. Vereshchagin V. M. Fomin 《Thermophysics and Aeromechanics》2016,23(5):741-746
A study of the sorption properties of a composite sorbent prepared from pseudoboehmite and synthetic sodium-borosilicate glass microspheres was performed with the aim of using the sorbent in membrane-sorption processes of helium extraction from natural gas with its simultaneous drying. Experimentally, permeability of the composite sorbent under study with respect to helium and its impermeability to air and methane has been demonstrated. Under experimental conditions, the absolute moisture content of the gas mixture having passed through the sorbent has reduced from 21.1 to 0.013 g/m3. The rate of helium adsorption by the composite sorbent has increased nearly by two orders of magnitude in comparison with the initial microspheres. It was found that the degree of saturation of the sorbent with water vapor had almost no influence on the rate of helium adsorption. A possibility of optimal use of the composite sorbent by combining the process of natural-gas drying from water vapor and the process of helium extraction from natural gas is shown. This possibility permits shortening of the process sequence for natural gas pre-conditioning prior to helium extraction. 相似文献
23.
Fomin N Arrington J Asaturyan R Benmokhtar F Boeglin W Bosted P Bruell A Bukhari MH Christy ME Chudakov E Clasie B Connell SH Dalton MM Daniel A Day DB Dutta D Ent R El Fassi L Fenker H Filippone BW Garrow K Gaskell D Hill C Holt RJ Horn T Jones MK Jourdan J Kalantarians N Keppel CE Kiselev D Kotulla M Lindgren R Lung AF Malace S Markowitz P McKee P Meekins DG Mkrtchyan H Navasardyan T Niculescu G Opper AK Perdrisat C Potterveld DH Punjabi V Qian X Reimer PE Roche J Rodriguez VM Rondon O 《Physical review letters》2012,108(9):092502
We present new measurements of electron scattering from high-momentum nucleons in nuclei. These data allow an improved determination of the strength of two-nucleon correlations for several nuclei, including light nuclei where clustering effects can, for the first time, be examined. The data also include the kinematic region where three-nucleon correlations are expected to dominate. 相似文献
24.
A. E. Sokolov A. E. Baranchikov D. O. Gil V. K. Ivanov G. P. Kopitsa A. A. Petrunin E. V. Fomin 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2014,8(5):997-1001
Nanocrystalline cerium-dioxide samples with different coherent-scattering region sizes are analyzed by advanced techniques, specifically, small-angle neutron scattering, X-ray and neutron diffraction, and spectrometry of the chemical shift in the characteristic X-ray lines. The obtained data confirm the presence of the size effect, i.e., the dependence of lattice constants on the size of coherent-scattering regions. Meanwhile, no traces of oxygen nonstoichiometry and a related deviation in the effective degree of cerium oxidation from the standard value are found. The results obtained call into question the Tsunekawa model traditionally used to explain the size effect in this compound. 相似文献
25.
We use tools of the equilibrium statistical mechanics of disordered systems to study analytically the statistical properties of an ecosystem composed of N species interacting via random mutual interactions, as well as via deterministic self-interactions of order p>/=2. We show that the main effect of increasing the order of the interactions among the species is to make the system less competitive, in the sense that the fraction of extinct species is greatly reduced. In addition, we find that for p>2 there is a threshold value which gives a lower bound to the concentration of the surviving species, preventing then the existence of rare species and, consequently, increasing the robustness of the ecosystem to external perturbations. 相似文献
26.
27.
Kleemans NA Bominaar-Silkens IM Fomin VM Gladilin VN Granados D Taboada AG García JM Offermans P Zeitler U Christianen PC Maan JC Devreese JT Koenraad PM 《Physical review letters》2007,99(14):146808
We report the direct measurement of the persistent current carried by a single electron by means of magnetization experiments on self-assembled InAs/GaAs quantum rings. We measured the first Aharonov-Bohm oscillation at a field of 14 T, in perfect agreement with our model based on the structural properties determined by cross-sectional scanning tunneling microscopy measurements. The observed oscillation magnitude of the magnetic moment per electron is remarkably large for the topology of our nanostructures, which are singly connected and exhibit a pronounced shape asymmetry. 相似文献
28.
G. A. Fomin 《Mathematical Notes》1978,23(2):117-123
Trigonometric series with coefficientsa k → 0 under the condition $$(\exists p \in R,p > 1):\left( {\sum\nolimits_{n = 1}^\infty {\left\{ {\sum\nolimits_{k = n}^\infty {|\Delta a_k |p_{/n} } } \right\}^{1/p}< \infty } } \right)$$ are considered. It is shown that, under these conditions, the cosine series is a Fourier series for which the conditiona n In n → 0 is the criterion for convergence in the metric of L. For the sine series, this is true under the further assumption that ∑ n=1 ∞ |a n |/n<∞. 相似文献
29.
Preliminary experimental results on recording of phase and amplitude holograms using the radiation of electric-discharge HF lasers are presented, and prospects for applications of such lasers in diagnostics of various objects are discussed. It is shown that lasers with homogeneous working medium may generate coherent radiation with a coherence length of greater than 6 m in the absence of mode selection. Methods for control of spatial distribution of electron concentration in excimer and discharge chemical HF (DF) lasers and distributions of the main combustible components are considered. Deposition of holographic identification marks on artworks is studied. 相似文献
30.
Russian Physics Journal - Based on the equations of macroscopic electrodynamics, the spectral-angular characteristics of electromagnetic radiation are considered, which is generated during the... 相似文献