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581.
Russian Chemical Bulletin - Supramer analysis was applied to explain the earlier discovered phenomenon of the transformation of nonselective glycosylation into stereospecific one upon changing the...  相似文献   
582.
Optics and Spectroscopy - Nanocomposites consisting of AgInS2 core and nanostructured TiO2 shell were synthesized. Preliminary characterization revealed that AgInS2/TiO2 nanocomposites with an...  相似文献   
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In the present paper we report about the last advances concerning the structure and properties of electrochromic photosensitive metallopolymers based on the complexes of Pt, Pd, Ni, Co, Cu with Schiff's bases. The criteria of selection of the object for the synthesis of new polymers with one-dimensional, reversible, controlled photo- and electroinduced charge transfer was determined. A model for the polymer structure was proposed. The ohmic resistance in the direction parallel and perpendicular to the microelectrode surface of gold-coated α-Al2O3 differs as 1: 106-109 depending on the polymer and film thickness. A qualitative model of the processes of light energy accumulation was proposed.  相似文献   
585.
The lattice parameters a and c as well as the compressibilities for different directions in the AgInS2 chalopyrite-type compound are determined as a function of pressure up to 5 GPa using a powder X-ray technique under high pressure. It is found that the compressibility is anisotropic, with compressibility along the tetragonal c-axis (𝓏c) being smaller than that along the a-axis (𝓏a). It is shown that as pressure rises the axial ratio c/a increases and as a result the tetragonal distortion δ = 2 - c/a reduces.  相似文献   
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The reactions of polyfluorochalcones with o-aminothiophenol in methanol in the presence of HCl afford polyfluorine-substituted 2,3-dihydrobenzo[b][1,5]thiazepines. In some cases, the cyclization is accompanied by fluorine substitution in the perfluorophenyl ring. Probably, the formation of thiazepines proceeds through the Michael thia-adduct. The Zn salt of o-aminothiophenol reacts with chalcones in DMF exclusively via fluorine substitution.  相似文献   
589.
High-porosity samples of beech wood biocarbon (BE-C) were prepared by pyrolysis at carbonization temperatures T carb = 650, 1300, and 1600°C, and their resistivity ρ and thermal conductivity κ were studied in the 5–300 and 80–300 K temperature intervals. The experimental results obtained were evaluated by invoking X-ray diffraction data and information on the temperature dependences ρ(T) and κ(T) for BE-C samples prepared at T carb = 800, 1000, and 2400°C, which were collected by the authors earlier. An analysis of the κ(T carb) behavior led to the conclusion that the samples under study undergo an amorphous-nanocrystalline phase transition in the interval 800°C < T carb < 1000°C. Evaluation of the electronic component of the thermal conductivity revealed that the Lorentz number of the sample prepared at T carb = 2400°C exceeds by far the classical Sommerfeld value, which is characteristic of metals and highly degenerate semiconductors.  相似文献   
590.
A new method for modifying polyelectrolyte capsule shells by magnetic nanoparticles is proposed: the in situ synthesis of magnetite by chemical condensation. The capsule cores were spherical calcium carbonate microparticles, while polymer shells were prepared using the layer-by-layer electrostatic adsorption of polyallylamine and polystyrene sulfonate. After in situ synthesis, nanoparticles of different shapes are formed on the capsule shell; the main crystalline phase of nanoparticles is magnetite. The thus obtained nanocomposite capsules are highly sensitive to external magnetic fields.  相似文献   
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