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V. N. Bochkarev A. V. Kisin V. G. Osipov N. P. Telegina N. G. Komalenkova A. N. Polivanov E. A. Chernyshev 《Chemistry of Heterocyclic Compounds》1978,14(1):17-18
Workup of the mixture of products of pyrolysis of cyclotetrasiloxane (Me2SiO)2(MePhSiO)2 yielded 1,3- (I) and 1,5-(o-phenylene)cyclosiloxane (II), the structures of which were established on the basis of data from their IR, PMR, and mass spectra.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 24–25, January, 1978. 相似文献
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Reactions of organochlorosilanes with chloro-and organogermanes in the presence of aluminum chloride
V. I. Zhun’ I. V. Sbitneva A. N. Polivanov E. A. Chernyshev 《Russian Journal of General Chemistry》2006,76(10):1564-1570
The effect of substituents at the silicon and germanium atoms in reactions of organochlorosilanes with chloro-and organogermanes in the presence of aluminum chloride was studied. The only occurring process is the exchange of the chlorine atoms at Ge for the phenyl groups from Si; an increase in the number of methyl groups or chlorine atoms at Si promotes formation of phenyltrichlorogermane, and an increase in the number of phenyl groups or replacement of the chlorine atom at the Si atom by hydrogen leads to the formation of di-and triphenylchlorogermanes. Neither phenyl nor other radicals are transferred back from Ge to Si in the course of reactions of phenylgermanes with methylchlorosilanes in the presence of aluminum chloride; the only occurring processes are the exchange of the phenyl or methyl radicals bonded to Ge for the Cl atom bonded to Al and the disproportionation of phenylchlorogermanes. 相似文献
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The search for ways of controlling a flow over flight vehicles is today an extremely topical issue, since the limiting capabilities
of standard control methods are the bulk of the progress of space technology. A promising technique in this respect is the
application of activators using a low-temperature plasma. Specifically, these electrogasdynamic devices can directly convert
electrical energy to a mechanical action on the flow. An activator based on a dielectric barrier discharge is considered.
The nonstationary behavior of the activator is studied by measuring the electrodynamic parameters of the discharge and also
by measuring induced velocity fields with particle image velocimetry. The instantaneous and integral parameters of the gas
acceleration stage are found, and the efficiency of the activator is determined. 相似文献
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D. Voelkel Yu.L. Chuzavkov J. Marquez S.N. Orlov Yu.N. Polivanov V.V. Smirnov F. Huisken 《Applied physics. B, Lasers and optics》1997,65(1):93-99
2 H2), methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O) in a cell under equilibrium conditions and cooled in free jet expansions. For methane at room temperature the detection
limit was 2×1012 molecules per cm3 and quantum state, enabling the detection of trace species with a spatial resolution of 1 mm2×30 mm. In an attempt to study transitions in the ν1+ν3 and 2ν2+ν3 combination bands of CO2 or N2O, it was not possible to observe any DFWM signal. Instead a surprisingly strong, backward- and forward-directed emission
was found which could not be attributed to the DFWM process. The signal arising from this emission was more than 2 orders
of magnitude stronger than the DFWM signals obtained for other molecules. The frequencies of the emitted radiation were found
to correlate with the transitions ν1+ν3→ν1 and 2ν2+ν3→2ν2, respectively. Our investigations lead to the conclusion that the emission can be explained by stimulated Raman scattering,
resonantly enhanced by transitions to the combination levels ν1+ν3 and 2ν2+ν3.
This process seems to suppress the generation of DFWM signals.
Received: 1 October 1996/Revised version: 6 January 1997 相似文献