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1.
N. G. Zharova É. D. German A. M. Kuznetsov I. O. Shapiro 《Russian Chemical Bulletin》1989,38(2):270-276
1. | The influence of the components of the effect of the structural reorganization of the anionic fragments of monalkylbenzenes and nitroalkanes on the kinetics of their ionization was determined. |
2. | A model of the mechanism of the elementary act in the ionization of monoalkylbenzenes and nitroalkanes in a polar medium, which takes into account the effects of the reorganization of the solvent, the geometric structure of the reactants, and the redistribution of the electron density in them, has been proposed. |
2.
A. V. Chistyakov M. A. Gubanov V. Yu. Murzin P. A. Zharova M. V. Tsodikov V. V. Kriventsov A. E. Gekhman I. I. Moiseev 《Russian Chemical Bulletin》2014,63(1):88-93
The features of ethanol conversion into hydrocarbons C4-C12 in the presence of the novel catalyst Pd-Zn/γ-alumina and pilot zeolite system Pd-Zn/MFI/γ-alumina were studied (MFI is high-siliceous zeolite with ZSM-5 type structure). The structure of active sites changes noticeably in the course of preliminary activation and catalytic reaction. High selectivity and stability of the zeolite-containing Pd-Zn catalyst in alcohol conversion into hydrocarbon components of fuels is related to the stable composition of the alloy that forms clusters PdZn. At the same time, the alumina-based catalyst loses stability due to zinc diffusion from the alloy into γ-Al2O3 to form the spinel structure. 相似文献
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A solution to the problem of realizing the collapse of three-dimensional wave packets in nonlinear media with normal group velocity dispersion is proposed. Wave packets with pronounced hyperbolic topology are shown to collapse; i.e., the field increases infinitely near the system axis. In particular, wave collapse of the tubular axisymmetric packets occurs through the concentration of the compressed ring field distribution at the axis. The collapse is shown to stabilize due to the saturation of nonlinearity or nonlinear dissipation, which restrict the field increase and lead to the packet splitting in the transverse direction. 相似文献
4.
A. V. Chistyakov P. A. Zharova M. A. Gubanov S. A. Nikolaev T. B. Egorova A. E. Gekhman M. V. Tsodikov 《Kinetics and Catalysis》2017,58(6):741-748
The results of a study on the activity and operational stability of an Au–Pd/MFI/Al2O3 catalyst in the reaction of ethanol conversion into a gasoline fraction of hydrocarbons are reported. In the presence of the Au–Pd/MFI/Al2O3 catalyst, ethanol was almost completely converted into an alkane–aromatic fraction of C3–C11 hydrocarbons at 300°C in an atmosphere of Ar; the yield of this fraction was as high as 90% on a feed carbon basis. It was established that, in the presence of the bimetallic Au–Pd catalyst, the yield of the target fraction increased by 10%, as compared with that on a monometallic Au-containing sample. The Au–Pd/MFI/Al2O3 catalyst exhibited much higher stability in a long-term experiment in comparison with the previously tested pilot sample of Pd–Zn/MFI/Al2O3. After a 40-h operation, the yield of the target fraction of C3+ hydrocarbons in the presence of the Au–Pd/MFI/Al2O3 catalyst decreased by 15%. The treatment of the catalyst with hydrogen led to the complete restoration of its activity. The structure of the Au–Pd active constituents was studied by transmission electron microscopy X-ray photoelectron spectroscopy. methods of the and microscopy. 相似文献
5.
We present the results of numerical and analytical analysis of solutions of the three-dimensional (3D) nonlinear Schröodinger equation with hyperbolic spatial operator. Evolution of the system is considered in separate for two types of the initial field: a Gaussian distribution and a hollow-type (tubular or horseshoe) distribution. The effect of the nonlinear dispersion on wave-packet splitting during self-compression toward the system axis is studied. It is shown that additional focusing of Gaussian wave packets takes place in a wide range of the nonlinear-dispersion parameter. This effect results in a noticeable amplitude growth of one of the two secondary pulses formed as a result of the splitting. For hollow-type distributions, we note the formation of moving inhomogeneities and the excitation of secondary wave fields typical of the hyperbolic system. 相似文献
6.
The self-focusing of laser radiation in plasma with ionized gaseous clusters is studied both analytically and numerically. An electrodynamic model is proposed for cluster plasma in a field of ultrashort laser pulse. The radiation self-action dynamics are studied using the equation for wave-field envelope with allowance for the electronic nonlinearity of the expanded plasma bunches and the group-velocity dispersion in a nanodispersive medium. It is shown that, for a laser power exceeding the self-focusing critical power, the wave-field self-compression occurs in a medium with dispersion of any type (normal, anomalous, or combined). Due to the strong dependence of the characteristic nonlinear field on the size of ionized cluster, the corresponding processes develop faster than in a homogeneous medium and give rise to the ultrashort pulses. 相似文献
7.
Conclusions The outer-sphere reorganization energies have been calculated for the ionization of toluene (167 kJ/mole) and cumene (146 kJ/mole) in solutions of potassium tert-butoxide in DMSO.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 326–328, February, 1989. 相似文献
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We theoretically study the electromagnetic cloaking of small (nano)particles in optical or IRbands by means of multilayered
coating simultaneously providing the shielding of cloaked volume and minimizing scattering. Within a quasi-static approximation
in sphe rical geometry, we show that two kinds of shielding shells exist with zero and with infinitely large (in the lossless
case) values of the dielectric constant. We demonstrate that narrowing of the shielding shell at zero dielectric permittivity
leads to the effect of electric field superlocalization when an infinite amount of energy is concentrated inside an infinitesimal
volume. 相似文献
10.
The prevailing concepts concerning the boundary layer near the free surface of a viscous liquid associated with oscillatory
motion are modified for calculating finite-amplitude linear oscillations of a charged bubble in this liquid. Equations of
the boundary layer theory for the neighbourhood of the oscillating free spherical surface of a charged bubble in a dielectric
liquid are derived, their analytic solution is obtained and compared with the exact solution, and the thickness of the boundary
layer is assessed. The range of applicability of the modified theory is determined. 相似文献