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1.
A. I. Kalinin 《Journal of Applied Mathematics and Mechanics》1989,53(6):695-703
An algorithm for the approximate solution (in the asymptotic sense) of a singularly perturbed linear time-optimal control problem is proposed. A computational procedure is outlined, which permits the use of the resulting asymptotic approximation for. the exact solution of the problem with a prescribed value of the small parameter. 相似文献
2.
A. V. Kalinin 《Radiophysics and Quantum Electronics》2004,47(12):955-965
We consider a method of far-zone wideband antenna measurements performed at discrete frequencies with subsequent synthesis of the tested-antenna response in the time domain for separating the useful signal and interference due to scattering. Experimental results of a study of the scattered fields arising during the measurements of characteristics of centimeter-wave horn antennas on a standard facility in an anechoic chamber are presented.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 47, No. 12, pp. 1066–1077, December, 2004. 相似文献
3.
M. S. Kalinin M. B. Krainev 《Bulletin of the Russian Academy of Sciences: Physics》2007,71(7):984-987
The behavior of the intensity of anomalous and galactic cosmic rays in the outer heliosphere is compared. The previous hypothesis, according to which the lowest energy galactic cosmic rays affected by large-scale electric fields far beyond the termination shock wave of the solar wind may contribute to the behavior of the anomalous component intensity, is analyzed. 相似文献
4.
The effect of the electron transverse and longitudinal velocity spread at the entrance to the interaction space on wide-band chaotic oscillations in intense multiple-velocity beams is studied theoretically and numerically under the conditions of formation of a virtual cathode. It is found that an increase in the electron velocity spread causes chaotization of virtual cathode oscillations. An insight into physical processes taking place in a virtual-cathode multiple-velocity beam is gained by numerical simulation. The chaotization of the oscillations is shown to be associated with additional electron structures, which were separated out by constructing charged particle distribution functions. 相似文献
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Mamedov V. A. Kalinin A. A. Gubaidullin A. T. Litvinov I. A. Azancheev N. M. Levin Ya. A. 《Russian Journal of Organic Chemistry》2004,40(1):114-123
3-(-Chlorobenzyl)-1,2-dihydroquinoxalin-2-one reacts with anions derived from acetylacetone, benzoylacetone, dibenzoylmethane, malononitrile, ethyl acetoacetate, and ethyl cyanoacetate to give the corresponding 3-(-R,R'CH-benzyl)-1,2-dihydroquinoxalin-2-ones which undergo intramolecular cyclocondensation to functionally substituted pyrrolo[1,2-a]quinoxalines on heating in boiling acetic acid. The reaction of 3-(-chloro-p-nitrobenzyl)-1,2-dihydroquinoxalin-2-one with acetylacetone anion directly leads to the corresponding pyrrolo[1,2-a]quinoxaline, without heating in acetic acid. 相似文献
8.
V. I. Kalinin S. A. Avilov A. I. Kalinovskii V. A. Stonik Yu. M. Mil'grom Ya. V. Rashkes 《Chemistry of Natural Compounds》1992,28(6):600-603
A minor glycoside — cucumarioside G4 (I) — has been isolated from the total triterpeneglycosides of the holothurianEupentacta fraudatrix, and its structure has been determined by physical and chemical methods as 16β-acetoxyholosta-7,23E-diene-3β, 25-diol 3-O-(3-O-methyl-β-D-xylopyranosyl)-(1→3)-O-β-D-glucopyranosyl-(1→4)-O-β-D-quinovopyransoyl-(1→2)-(4-O-(sodium sulfato)-β-D-xylopyranoside)]. 相似文献
9.
A. V. Kalinin Yu. A. Strelenko É. T. Apasov S. L. Ioffe 《Russian Chemical Bulletin》1991,40(9):1789-1795
Functionally substituted N-nitrohydrazines were studied by heteronuclear NMR. It was shown that all the investigated products from nitration of the trimethylsilyl derivatives of functionally substituted hydrazines contain the N-NO2 fragment. The chemical shift of the nitrogen atoms of the hydrazine fragment in the15N NMR spectra and the
spin-spin coupling constants were used as the main tests for structural identification. It was established that the number of recordable conformers decreases in the transition from the trimethylsilyl phenylhydrazine derivatives to the nitrohydrazines as a result of the conformational flexibility of the N(NO2)CO fragment.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2024–2031, September, 1991. 相似文献
10.
E. T. Apasov B. A. Dzhetigenov E. V. Shepelev Yu. A. Strelenko A. V. Kalinin 《Russian Chemical Bulletin》1993,42(4):703-706
Reactions ofm- andp-dinitrobenzenes witht-BuNHMgBr andt-BuNHLi were studied. The reactions afford azo- and azoxy-derivatives and products of nucleophilic substitution.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 739–741, April, 1993. 相似文献