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151.
A. G. Zakharov M. I. Voronova D. V. Batov K. V. Smirnova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2011,85(3):408-412
The solution of phenol and benzoic acid in water-dimethylsulfoxide (DMSO) and water-acetonitrile (AN) mixtures was studied.
As distinct from benzoic acid, the thermodynamic characteristics of solution of phenol sharply change at concentrations corresponding
to a change in the character of cluster formation in water-DMSO and water-AN mixtures. Differences in the solvation of phenol
and benzoic acid are explained by different mechanisms of the interaction of the solutes with clusters existing in binary
mixtures. 相似文献
152.
M. V. Radugin T. N. Lebedeva A. N. Prusov A. G. Zakharov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2011,85(5):897-899
Changes in enthalpy upon the dissolution of polyvinylpyrrolidone in a water-ethanol solvent were determined. The effect of
temperature, the molecular mass of the polymer, and the ethanol content in the mixed solvent on these characteristics was
demonstrated. 相似文献
153.
B. P. Aduev É. D. Aluker G. M. Belokurov Yu. A. Zakharov A. G. Krechetov 《Journal of Experimental and Theoretical Physics》1999,89(5):906-915
A real-time investigation of the explosive decomposition of heavy-metal azides is reported. A multichannel instrument configuration
designed specifically for the goals of the study is described; it is capable of measuring the transient conductivity and the
spectral and kinetic characteristics of the luminescence and absorption of exploding samples with nanosecond time resolution.
New phenomena are discovered and analyzed in detail: the predetonation conductivity and predetonation luminescence of heavy-metal
azides. The conductivity of silver azide in the predetonation state is used to make an experimentally justified decision as
to whether the explosion is driven by a thermal or chain mechanism, in favor of the latter. The sum-total of the new data
provides the basis for the development of an experimentally justified model of predetonation luminescence and the explosive
decomposition process of heavy-metal azides, including the following principal stages: hole trapping by a cation vacancy,
reconstruction of the center as a result of chemical reaction with the formation of a quasi-local hole state in the valence
band, hole detrapping from the reconstructed center, carrier multiplication as a result of impact ionization by hot holes,
and reconstruction of a local state in the bandgap, thereby establishing conditions for repetition of the investigated chain
of processes.
Zh. éksp. Teor. Fiz. 116, 1676–1693 (November 1999) 相似文献
154.
155.
Summary Exact solutions are obtained in the framework of the classical theory of laminates subjected to the action of normal moments,
double forces, double moments or momentless double dipoles. Seven cases of such loads are considered and completed by considering
the case of given transversal discontinuity of normal deflection. It is shown that, in contrast to the case of infinite straight
dislocations in a pure in-plane problem, the energy of this eighth solution depends on the discontinuity orientation. Some
numerical examples are presented. Besides the formal value, the obtained double-force and double-moment solutions, as well
as dimensionless double dipoles, can be used to construct kernels of additional boundary integral equations (BIE). Due to
the coupling phenomena in the BIE system for the region with a corner point, additional variable such as corner forces appear
and require the mentioned equation.
Received 22 June 1999; accepted for publication 6 March 2000 相似文献
156.
The light-oxygen effect consists in a direct excitation of molecular oxygen dissolved in aqueous media of biosystems by the
light; it provides the possibility to use lasers for therapeutic purposes. The wavelength of the used light should strictly
correspond to the oxygen absorption bands. However, laser therapy also makes use of lasers emitting at 0.89 μm (outside the known oxygen bands), which suggests the action of a new photoreceptor. Here we argue that this mechanism of
photoreception is a modification of the light-oxygen effect involving the absorption of photon simultaneously by the oxygen
molecule and O-H stretch of the H20 molecule of liquid water. 相似文献
157.
I. A. Prokhorov B. G. Zakharov V. E. Asadchikov A. V. Butashin B. S. Roshchin A. L. Tolstikhina M. L. Zanaveskin Yu. V. Grishchenko A. E. Muslimov I. V. Yakimchuk Yu. O. Volkov V. M. Kanevskii E. O. Tikhonov 《Crystallography Reports》2011,56(3):456-462
The possibility of characterizing a number of practically important parameters of sapphire substrates by X-ray methods is substantiated. These parameters include wafer bending, traces of an incompletely removed damaged layer that formed as a result of mechanical treatment (scratches and marks), surface roughness, damaged layer thickness, and the specific features of the substrate real structure. The features of the real structure of single-crystal sapphire substrates were investigated by nondestructive methods of double-crystal X-ray diffraction and plane-wave X-ray topography. The surface relief of the substrates was investigated by atomic force microscopy and X-ray scattering. The use of supplementing analytical methods yields the most complete information about the structural inhomogeneities and state of crystal surface, which is extremely important for optimizing the technology of substrate preparation for epitaxy. 相似文献
158.
159.
160.
Numerical simulation of the fully nonlinear water equations demonstrates the existence of giant breathers on the surface of
deep water. The numerical analysis shows that this breather (or soliton of envelope) does not loose energy. The existence
of such a breather can explain the appearance of freak waves.
The text was submitted by the authors in English. 相似文献