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1.
2.
Mihaela Gulea Isabelle Abrunhosa Jozef Drabowicz Guillaume Grach Matthieu Hamel Serge Masson 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5-6):1267-1272
Abstract A new method to prepare enantioenriched sulfinates was developed to obtain optically active ortho-methylsulfinyl(phenylphosphonates). It consists of a diastereoselective oxidation of sulfenates to sulfinates. Additionally, preliminary results concerning the synthesis of ortho-phophonylated benzylic thiol derivatives via a new P═S to P═C [1,4]-rearrangement and a first synthetic application of these compounds are also described. 相似文献
3.
We present the results of experimental studies of the spectra of the stimulated electromagnetic emission excited in the ionosphere
by powerful radio waves during the pump wave frequency sweeping near the forth (n = 4) and fifth (n = 5) harmonics of the electron cyclotron frequency nf
ce. The frequency sweep was carried out for long (continuous) pumping in vertical and inclined directions (at 14° and 18° south
of the zenith), as well as for the pulse diagnostic wave both with and without additional pumping far from the gyroharmonics.
The dependences of the spectral features of the stimulated electromagnetic emission on the ratio between the pump-wave frequency
f
0 (or on the diagnostic-wave frequency fDW) and nf
ce were analyzed. It is found that near the multiple gyroresonance, different spectral features of the stimulated emission are
quenched at the same frequency for different pump-wave frequencies. For a sufficiently large inclination of the pump wave
beam from the vertical direction, the intensity of the stimulated electromagnetic emission is notably decreased for f
0 ≲ nf
ce as compared with f
0 > nf
ce.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 51, No. 6, pp. 461–476, June 2008. 相似文献
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7.
A. V. Ryabov S. M. Grach A.V. Shindin D. S.Kotik 《Radiophysics and Quantum Electronics》2011,54(7):441-451
We present the results of experimental studies of artificial large-scale irregularities of the ionospheric electron number
density with dual-frequency GPS diagnosis. The total electron content was analyzed in the GPS signal trajectory when the satellites
passed over the heated region. Spectral composition of the observed variations was determined by wavelet analysis. Characteristic
scales of artificial irregularities of the electron number density in the F layer are estimated. It is experimentally proved that the irregularities remain for at least 15–20 min after the transmitter
is switched off. A more confident excitation and increased intensity of the irregularities were also confirmed when the beam
was inclined south of the magnetic-zenith direction. 相似文献
8.
E. N. Sergeev S. M. Grach G. P. Komrakov V. L. Frolov P. Stubbe B. Thidé T. Leyser T. Carozzi 《Radiophysics and Quantum Electronics》1999,42(7):544-556
We present the results of experimental studies of the evolution of stimulated electromagnetic emission of the ionosphere (SEE)
under the F-layer modification by powerful HF radio waves in a broad range of the pump wave frequencies. We compare the parameters
of the overshoot effect in SEE evolution to the observations of anomalous attenuation and field-aligned scattering of radio
waves. We show the overshoot effect to result from the anomalous attenuation under scattering at artificial small-scale ionospheric
irregularities. We found the characteristic time scales of the overshoot effect development to decrease and its value to increase
as the pump wave frequency decreases from 6 to 4 MHz; this is attributed to the observed increase of the irregularities amplitude
at scales
m.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 42, No. 7, pp. 619–634, July 1999. 相似文献
9.
10.
A. G. Bronin S. M. Grach G. A. Zhbankov N. A. Zabotin 《Radiophysics and Quantum Electronics》1999,42(8):728-736
We obtain and analyze numerically exact formulas for anomalous absorption of a probing ordinary wave due to its transformation
into plasma waves under vertical sounding of an ionospheric plasma layer with given spectrum of irregularities. The nature
of possible approximations and their validity limits are analyzed.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 42, No. 8, pp. 826–836, August 1999. 相似文献