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1.
The electrodynamic properties of the interface between two periodic dielectric superlattices are studied. It is shown that
the interface may serve as a guide for an electromagnetic wave whose field decays exponentially on both sides of the plane
of the interface. The field and power flux distributions, as well as the frequency dependence of the field penetration depth,
are studied. 相似文献
2.
The effect of carrier drift on the dispersive properties and instability of electromagnetic waves and plasma polaritons in infinite layered periodic semiconductors are considered. It is assumed that in similar semiconductor layers, carriers drift parallel to the interfaces. Drift waves are shown to have a specific band structure of the spectrum. The dispersive properties of collective plasma polaritons under drift are considered, the instability of the polaritons and drift waves is studied, and the instability increments are determined. 相似文献
3.
The band spectrum of natural waves in a periodic structure formed by alternating dielectric and semiconductor layers is investigated
for the propagation of waves at some angle with respect to a magnetic field applied along the periodicity axis. A method is
presented for deriving a dispersion equation, and its properties are analyzed numerically. It is shown that, in the absence
of dissipation, there are two independent spectra of natural waves in the structure being considered, and the regions of existence
of various types of such waves are classified. It is established that the transmission bands of the two spectra may supplement
one another or overlap. It is found that, for the chosen magnetic-field direction, there exist numerous bands of transmission
of cyclotron waves. 相似文献
4.
S. A. Bulgakov P. V. Ponomarenko Yu. M. Yampolsky 《Radiophysics and Quantum Electronics》1995,38(6):368-373
The fractal dimension as a characteristic of an experimental data series is considered. The correlation integral method is used for dimension calculation. It is shown that by the fractal dimension one can identify a variety of ionospheric processes even when the conventional spectral analysis fails. It is found that the realizations corresponding to volume scattering by natural and artificial irregularities have finite dimension, which is significantly different. A technique for preparing experimental data to be processed by the correlation integral method is developed. The influence of the data sampling rate and signal-to-noise ratio on the dimension is analyzed.Radioastronomical Institute, Ukrainian Academy of Sciences, Khar'kov. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 38, No. 6, pp. 557–565, June, 1995. 相似文献
5.
6.
A. A. Altynnikov O. V. Kalinkina V. F. Anufrienko A. A. Shubin S. V. Vossel V. V. Zakharov N. N. Bulgakov 《Reaction Kinetics and Catalysis Letters》1994,52(2):261-267
The ESR spectrum of exchange-coupled Ti3+ ions of gge has been observed in dissolution products of metallic titanium in HCl, evidencing the formation of chloride clusters of mutually ordered Ti3+ ions in dz2-ground state in distorted tetrahedral coordination. The cooperative Jahn-Teller effect (CJTE) defines orbital ordering of the d1 of Ti3+ ions in the cluster. 相似文献
7.
A. A. Medvinskii N. N. Bulgakov Y. M. Baikov 《Reaction Kinetics and Catalysis Letters》1982,20(3-4):267-271
The interacting bonds method (IBM) has been used for the analysis of hydrogen bonds in liquid ammonia, including estimates of the resonance components of the H=bonds of ammonia molecules with ammonium and amide ions. According to the Ea estimates for the interaction of a hydrogen molecule with an amide-ammonia solution (AAS) and the data on liquid ammonia structure, a kinetic mechanism for isotope exchange (IE) of hydrogen with liquid ammonia is formulated.
(MBC) , -, - -. Ea - (AAP). () .相似文献
8.
Chemiluminescence (CL) in oxidation of organosodium compounds by O2 in THF was studied. Emitters of CL are excited complexes of polycyclic aromatic hydrocarbons, excimers1(R·R)*. The mechanism of their formation was proposed. The Na+, R.−+O2 CL system is a unique source for the selective generation of excimers of aromatic hydrocarbons.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 284–288, February, 1997. 相似文献
9.
V. P. Kazakov S. V. Lotnik V. N. Korobeinikova V. M. Kalinina L. A. Khamidullina R. G. Bulgakov A. N. Petrov 《Russian Chemical Bulletin》1991,40(8):1720-1720
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, p. 1934, August, 1991. 相似文献
10.
R. G. Bulgakov Yu. G. Ponomareva Z. S. Muslimov F. G. Valyamova R. A. Sadykov R. F. Tuktarov 《Russian Chemical Bulletin》2007,56(2):211-219
Fullerenyl radicals (FR) RC60
· and chemiluminescence (CL) are generated in the presence of O2 in C60—R3Al (R = Et, Bui) solutions in toluene (T = 298 K). The FR are formed due to the addition of the R· radical, which is an intermediate of R3Al autooxidation, to C60. Mass spectroscopy and HPLC were used to identify EtnC60Hm (n, m = 1–6), EtpC60 (p = 2–6), and dimer EtC60C60Et as stable products of FR transformations. As found by ESR, the EtC60
· radical (g = 2.0037) is also generated by photolysis of solutions obtained after interaction in the (C60— R3Al)—O2 system. In the presence of dioxygen, the FR is not oxidized but yields complexes with O2, which appear as broadening of the ESR signals. Chemiluminescence arising in the (C60—R3Al)—O2 system is much brighter (I
max = 1.86·108 photon s−1 mL−1) than the known background CL (I
max = 6.0·106 photon s−1 mL−1) for the autooxidation of R3Al and is localized in a longer-wavelength spectral region (λmax = 617 and 664 nm). This CL is generated as a result of energy transfer from the primary emitter 3CH3CHO* to the products of FR transformation: RnC60Hm, RpC60, and EtC60C60Et.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 205–213, February, 2007. 相似文献