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131.
The kinetic and activation parameters of oxidation of cadmium with dicarbonylcyclopentadienyliron chloride in dimethylformamide were determined. The apparent equilibrium constants, enthalpy, and entropy of adsorption of the reactants on the metal surface were evaluated. The reaction scheme was suggested.  相似文献   
132.
133.
An arbitrary polarization state of a single-mode biphoton is considered. The operationalistic criterion is formulated for the orthogonality of these states. It can be used to separate a biphoton with an arbitrary degree of polarization from a set of biphotons orthogonal to it. This is necessary for the implementation of quantum cryptography protocol based on the three-level systems. The experimental test of this criterion amounts to the observation of the anticorrelation effect for a biphoton with an arbitrary polarization state.  相似文献   
134.
A procedure was developed for preparing [Cp(CO)2Fe]2SnCl2 by direct oxidation of tin with 5-cyclopentadienyldicarbonyliron chloride in polar solvents. The reaction kinetics was studied, and its scheme was suggested. Products of the reaction of magnesium with compounds R2SnCl2 [R = Cp(CO)3Mo, Cp(CO)3W, Cp(CO)2Fe] were identified. The reaction mechanism was discussed.  相似文献   
135.
136.
The luminescence of the CdTe quantum dots deposited on glass substrate and introduced into the porous silicon oxide matrix is investigated. The experimental results on the photoluminescence with one- and two-photon excitation and cathodoluminescence indicate that the quantum dots introduced into the matrix retain the luminescence properties. The coefficient of the two-photon absorption of the CdTe quantum dots on the glass substrate is determined.  相似文献   
137.
The effect of a direct-current (dc) electric field on the electrophysical characteristics of nematic liquid crystals of the alkyl cyanobiphenyl series nCB (n = 6–8) and the multicomponent liquid-crystal mixture MB-1, which are doped with ionic surfactants, has been investigated using impedance spectroscopy. It has been found that the impedance spectra depend substantially on the dc bias voltage applied to the sample. The approximation of the measured spectra with specially developed equivalent circuits of the measuring cell with a sample has made it possible to determine the capacitance of the electric double layer and the electrical conductivity of the samples, as well as the mobility, concentration, and diffusion coefficient of the ions. It has been shown that a region of the space charge is formed in the frequency range f < 100 Hz near the electrodes of the measuring cell with a liquid-crystal sample, which leads to an increase in the active (resistive) and reactive (capacitive) components of the impedance.  相似文献   
138.
Quantum yields, apparent photolysis rate constants, and energies of activation of the dark stages in the decomposition of 3,6-di-tert-butyl-2,3-epoxy-5-hydroxycyclohex-2-ene-1,4-dione, 1,4-naphthoquinone, and 9,10-anthraquinone under irradiation at λ 313 nm and of 1,4-benzoquinone under irradiation at λ 232–254 nm were determined. Products of photochemical transformations of these compounds in saturated hydrocarbons were identified, and a probable mechanism of these transformations was proposed.  相似文献   
139.
From the linear correlation of the chemical shift (19F) in compounds R-C≡C-C6H4-F-p (reference PhF, solvent to-luene) with the Hammett σ p constants of substituents R, the σ p constants of organometallic substituents R [Cp(CO)3Mo, Cp(CO)3W, Cp(CO)2Fe, Cp(PPh3)Ni, Ph2Bi, Ph2Sb, Ph3Sn] were calculated. The logarithm of the rate constant of magnesium oxidation with compounds RCl linearly correlates with the σ p constants of the organometallic groups R.  相似文献   
140.
Dynamics of the ensemble of two model neurons interacting through electrical synapse is investigated. Both neurons are described by two-dimensional discontinuous map. It is shown that in four-dimensional phase space a chaotic attractor of relaxation type exists corresponding to spike-bursting chaotic oscillations. A new effect of recurrent transitory chaotic oscillations underlies a dynamical mechanism of chaotic bursts formation. It is shown that, under coupling, the transient from chaotic bursts generation into rest state occurs with a time delay. A new characteristic estimating the degree of spike-bursting synchronization is introduced. Dependence of the synchronism degree on the coupling strength is shown for some coupling interval where only activity synchronization occurs. A probabilistic study provides a dynamical explanation of these phenomena.  相似文献   
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