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81.
82.
We construct an example of a Rademacher subspace without the Banach-Saks property and study the relationship between the Banach-Saks indices of a space with a symmetric basis and its dual.  相似文献   
83.
84.
A general approach to 3-azabicyclo[3.1.1]heptanes by reduction of spirocyclic oxetanyl nitriles was developed. The mechanism, scope, and scalability of this transformation were studied. The core was incorporated into the structure of the antihistamine drug Rupatidine instead of the pyridine ring, which led to a dramatic improvement in physicochemical properties.  相似文献   
85.
86.
87.
We propose a new method of resonant enhancement of optical Kerr nonlinearity that uses multilevel atomic coherence. The enhancement is accompanied by suppression of the other linear and nonlinear susceptibility terms of the medium. We show that the effect results in a modification of the nonlinear Faraday rotation of light propagating in an 87Rb vapor cell by changing the ellipticity of the light.  相似文献   
88.
89.
Wariation of the concentration of fullerenes C60 and C70 in poly(methyl methacrylate) films under UV exposure in atmospheric oxygen was studied. The mechanism of the influence exerted by addition of some photostabilizing polymers and xanthene dyes on the photooxidative degradation of fullerene in the polymer matrix was analyzed.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 6, 2005, pp. 1038–1042.Original Russian Text Copyright © 2005 by Troitskii, Khokhlova, Konev, Denisova, Novikova, Lopatin.  相似文献   
90.
X-ray diffraction topography and diffuse scattering techniques were used to study the defect structure formation of plastically deformed Al single crystals. The investigated X-ray scattering has been found out materially to depend upon the character of the dislocation structure (upon the geometry of the dislocation distribution). This dependence is manifested in different distribution of the intensity and in the changed form of the isointensity curves of diffuse and regular (Laue) reflections. In spite of the fact that the distribution of the internal stresses acting in different glide systems under conditions of uniaxial stretching is of complicated character, it is possible to trace the development of the glide process in the body of a sample and to obtain satisfactory interference patterns both of regular reflexions (on topograms) and of diffuse ones (on Laue photographs) up to severe deformations of a crystal at 300, 4.2, and 1.6 K. The following diffuse effects connected with structural changes in deformed crystals have been ascertained on the X-ray photographs:
  • —diffuse regions are elongated in the reciprocal lattice space along the glide directions or other crystallographic directions;
  • —these diffuse regions are split into separate areas along the directions of the said elongations;
  • —the diffuse regions are changed in length: the diffuse reflexes are diffused or condensed;
  • —the diffuse scattering isointensity curves are “zigzag”-shaped.
  相似文献   
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