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1.
JETP Letters - A constraint $$g_{A}^{2}\leq 4.5\times10^{-24}\big(g^{2}+1/\lambda_{A}^{2}\big)$$ on the constant gA of a new short-range (spin—orbit) interaction between nucleons, which is... 相似文献
2.
A mathematical model of the formation of primary grown-in microdefects on the basis of dissociation diffusion is presented.
Cases of “vacancy-oxygen” (V + O) and “carbon-interstitial” (C + I) interaction near the crystallization front are considered
for dislocation-free Si single crystals grown by the floating-zone and Czochralski methods. The approximate analytical expressions
obtained by setting 1D and 2D temperature fields in a crystal are in good agreement with the heterogeneous mechanism of formation
of grown-in microdefects. 相似文献
3.
A number of rigorous results concerning the mathematical structure of quantum systems with the BRST symmetry are presented. For studying model-independent properties of such systems, a generalization of the Strocchi-Wightman theory is suggested, which is a Wightman type theory in the Krein space with an OpJ*-algebra of physical and ghost fields. It is proved that the BRST charge operatorQ is either bounded with (Q)={0} or unbounded with (Q)=¢. A number of conditions equivalent to the no-ghost theorem (which states that the kernel ofQ is non-negative) are derived. 相似文献
4.
One of the methods of designing aircraft with supersonic flight speeds involves solving an inverse problem by means of the well-known flow schemes and the substitution of rigid surfaces for the flow surfaces. Lifting bodies using the flows behind axisymmetric shock waves belong to these configurations. All lifting bodies using the flow behind a conical shock wave can be divided into two types [1]. Bodies whose leading edge passes through the apex of the conical shock wave pertain to the first type and those whose leading edge lies below the apex of the conical shock wave, to the second. For small apex angles of the basic cone at hypersonic flow velocities an approximate solution of the variation problem was obtained, which showed that the lift-drag ratio of lifting bodies of the second type is higher than that of the first [2]. The present paper gives a numerical solution of the problem for flow past lifting bodies of the second type using the flow behind axisymmetric conical shock waves with half-angles of the basic cone S=9.5 and 18° The upper surfaces of the bodies are formed by intersecting planes parallel to the velocity vector of the oncoming flow.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 2, pp. 135–138, March–April, 1986. 相似文献
5.
G. N. Pirogova R. I. Korosteleva N. M. Panich T. A. Lagutina Yu. V. Voronin 《Russian Chemical Bulletin》1994,43(4):551-554
The catalytic activity of MIMIIO3] perovskite-type complex oxides (MI = La, Y, Nd, Yb; MII = Co, Mn, Ni) in the oxidation of CO, propylene, benzene, ethylbenzene,o-xylene, and ethyl acetate was investigated. The Co-containing catalysts were shown to be more active in the oxidation than the Mn-containing catalysts. A relationship between the catalytic and adsorption properties was established.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 602–605, April, 1994. 相似文献
6.
Gun'ko V. M. Mikhalovskii S. V. Melillo M. Voronin E. F. Nosach L. V. Pakhlov E. M. 《Theoretical and Experimental Chemistry》2004,40(3):137-143
The interaction of ibuprofen [2-(4-isobutylphenyl)propionic acid] with the surface of carbon and oxide adsorbents was investigated. The significant role of wide pores during the adsorption of ibuprofen on carbon adsorbents in the presence of protein molecules was demonstrated. At low concentrations ibuprofen is adsorbed on the surface of hydrophilic and hydrophobic adsorbents in the form of a monomer, but the contribution from the adsorbed dimer increases with increase in its concentration. 相似文献
7.
O. N. Leonidova V. I. Voronin I. A. Leonidov R. F. Samigullina B. V. Slobodin 《Journal of Structural Chemistry》2003,44(2):243-247
The crystal structures of vanadates Li1-2xCo1+xVO4 with x = 0 and 0.25 have been studied by a full pattern analysis. It has been shown that in cubic spinel LiCoVO4 (space group Fd3m), the 8a tetrahedral sites contain a majority of vanadium and a small amount of lithium; all cobalt, lithium, and a small amount of vanadium occupy the 16d octahedral sites. Li0.5Co1.25VO4 crystals belong to the rhombic system (Imma space group) with unit cell parameters a = 5.939(1), b = 5.810(1), and c = 8.303(1). On substitution of lithium by cobalt according to the scheme 2Li+ Co2+ + , half of the lithium and 70% of the vacancies formed are in the 4a octahedral sites, and onethird of lithium and most of cobalt occupy the 4d octahedral sites. The 4e tetrahedral sites are completely occupied by vanadium and lithium in a ratio of 0.92/0.08. The interatomic distances in LiCoVO4 and Li0.5Co1.25VO4 are calculated, and the sizes of lithium ion transport channels are evaluated. 相似文献
8.
V. G. Voronin S. B. Goncharenko A. I. Ermakov Yu. N. Portnov 《Chemistry of Heterocyclic Compounds》1976,12(4):443-448
The mass spectra of 2- and 4-thiobarbituric acids and some of their close analogs at ionizing voltages of 70 and 14 eV are compared. Qualitative and quantitative differences in the behavior of these compounds under the influence of electron impact were established. It is shown that the position of the thione group in the ring and the tautomeric transformations have a substantial effect on the character of the fragmentation of the investigated compounds. The established fragmentation principles make it possible to distinguish the structural isomers in a series of 2- and 4-thiobarbituric acids from their mass spectra.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 529–535, April, 1976. 相似文献
9.
V.L. Auslender I.V. Gornakov V.M. Radchenko E. Shtarklev V.O. Tkachenko L.A. Voronin 《Radiation Physics and Chemistry》2007,76(11-12):1792-1794
The report describes electron beam electromagnetic forming system, which is destined for irradiation of cylindrical long goods, specifically for PE tubes 160 mm diameter. System consists of electromagnet, power supply units, beam distributions control units, etc. for use at an electron accelerator at 5 MeV and 50 kW. The particular geometry of the magnet poles and their mutual arrangement are creating an irradiation field that allows the electrons to irradiate the surface of the product close to 90°. 相似文献
10.
G. N. Pirogora N. M. Panich R. I. Korosteleva Yu. V. Voronin 《Russian Chemical Bulletin》1996,45(11):2525-2528
Manganites with a spinel structure MMn2O4 (M = Co, Cu, Zn, Mo) and M1
0.5M2
0.5 Mn2O4 (M = Co, Cu, Zn, Mg) have been synthesized and tested in the catalytic oxidation of CO, C3H6, and ethylbenzene. The dependence of the catalytic activity of the manganites on the nature of the cation has been established. The spinels containing transition metal ions (Cu, Co) are more active. A relation between catalytic and adsorption properties of manganites has been established. The participation of the lattice oxygen in the oxidation of CO to CO2 has been found. The mechanism of the oxidation is discussed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No, 11, pp, 2686–2669. November, 1996. 相似文献