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An approach to parameterization of the structure of chaotic surfaces was presented which employs the flicker-noise spectroscopic technique for analyzing the atomic-force microscopy data arrays. This approach implies calculation of the surface relief parameters with the use of the information parameters characterizing the components of the surface relief profiles for different spatial frequency ranges. The basic characteristics of the nanoscale surface structure include the nanorelief stepwiseness and spikiness describing the highest-frequency component of the nanorelief. The capabilities of the FNS methodology were demonstrated by the example of parameterization of AFM data arrays for binary and triple systems crystallized on mica from aqueous acidic solutions of chitosan, Pluronic, and porphyrin photosensitizer (dimegin). These systems attract much interest in the context of studies dedicated photoinduced oxidation of organic substrates in aqueous solutions.  相似文献   
113.
Russian Journal of Physical Chemistry A - The effect amphiphic polymer poly-N-vinylpyrrolidone (PVP) and polysaccharides (PSs), sodium alginate (SA) and hyaluronic acid (HA), have on the...  相似文献   
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Russian Journal of General Chemistry - The reaction of 6-amino-3-methyl-4-(2,4-dichlorophenyl)-2,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile with phosphorus sulfide in boiling pyridine...  相似文献   
116.
Russian Journal of General Chemistry - The reaction of partially saturated derivatives of 3-aminothieno[2,3-b]pyridine-2-carboxamide with phthalic anhydride in acetic acid or DMF on heating leads...  相似文献   
117.
Solubilization of hydrophilic porphyrins, 2,7,12,18-tetramethyl-3,8-di(1-methoxyethyl)-13,17-di(2-oxycarbonylethyl) porphyrin disodium salt (dimegin) and N-methyl-di-D-glucose amine salt of chlorine e 6 (photoditazine), as well water-insoluble meso-tetraphenylorphyrin in the micelles of Pluronics (triblock copolymers and propylene oxide and ethylene oxide), increases the photocatalytic activity of porphyrins in the course of the oxidation of L-tryptophan in aqueous salt-containing solutions. The maximum photocatalytic activity is attained for the photocatalysts based on the Pluronics P85 and F127 containing 50–70% ethylene oxide units. As a result of solubilization, the activity of tetraphenylporphyrin increases by a factor of 50, while the activities of hydrophilic dimegin and photoditazine increase by factors of 1.5 and 6, respectively. The increased activity of tetraphenylporphyrin is due to the dissolution and dissociation of aggregates in the presence of Pluronics. The increased activity of dimegin, which is known to aggregate in water, is primarily provided by disaggregation. In the case of photoditazine, which does not form aggregates in aqueous solutions and is likely to be localized in the polar micellar “crown,” the effect of a polymer is due to the local concentration of both a substrate and a catalyst in the micellar pseudophase.  相似文献   
118.
The structural and phase state of the C60-C70 system at various C60/C70 ratios in mixtures obtained by the vaporization of solutions in toluene at ∼98°C was studied by X-ray structure analysis, differential scanning calorimetry, and infrared spectroscopy. Solid solutions based on the face-centered cubic packing of C60 are not formed in the C60-C70 system at C70 contents from 0.5 to 50 wt %. The hexagonal close packing of a solid solution of C60 in C70 can be formed as a result of the thermally activated decomposition of the ternary crystal solvate in the C60-C70-C6H5CH3 system. The structural state of multiphase mixtures formed under conditions far from equilibrium is characterized by a high degree of structure imperfection and greater ability to undergo oxidation compared with C60 and C70.  相似文献   
119.
Russian Journal of General Chemistry - The reaction of 5-amino-3-(cyanomethyl)-1H-pyrazole-4-carbonitrile with 3-aryl-5-hydroxy-5- methyl-2,4-di(ethoxycarbonyl)cyclohexanones in acetic acid...  相似文献   
120.
The Wiener-Hopf method is used to obtain a generalized Milne solution for scalar and electromagnetic fields with single-scattering anisotropy. For the scalar field, the solution found for the time correlation function and the interference component of backscattering is in good agreement with available experimental data. A solution of the Milne problem is constructed for the electromagnetic field. Given anisotropy, the generalized Milne equation is solved in the P1 approximation for the quantity that describes the degree of depolarization of the scattered light. It is shown that the depolarization of the scattered light can change sign at large anisotropies.  相似文献   
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