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51.
The surface of aerosilogel and macroporous and microporous glasses was modified with aromatic sulfo groups (≡Si(CH2)2-C6H4-SO3H) by the chemical assembly method. Composite solid electrolytes containing Nafion were prepared from the silica matrices with a chemically modified surface. The proton conductivity of the materials was studied by impedance spectroscopy. Composite materials based on Nafion and aerosilogel matrices and macroporous glasses with grafted ≡Si(CH2)2-C6H4-SO3H groups showed the highest proton conductivity.  相似文献   
52.
The reaction of methane conversion in anhydrous trifluoroacetic acid (TFA) is shown to take place at room temperature and atmospheric pressure and to result in the formation of a resinous product. Signals of ions with molecular weights of 684 and 700 are observed in MALDI-TOF spectra of the dry residue of methane conversion products.  相似文献   
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Russian Journal of Organic Chemistry - The reaction of 2-chloropyridine-3,4-dicarbonitrile with anilines in propan-2-ol in the presence of N,N- diisopropylethylamine (DIPEA) in a sealed vial at...  相似文献   
54.
Association of a micelle-forming monomer, n-dodecylammonium 2-acrylamido-2-methylpropanesulfonate, in aqueous solutions has been studied in a concentration range of 1.5 × 10?3–2.5 × 10?1 M with the use of conductometry, capillary and rotational viscometry, isothermal translational diffusion, and atomic force microscopy. Two critical micelle concentrations have been determined, and the shape of n-dodecylammonium 2-acrylamido-2-methylpropanesulfonate micelles has been proposed.  相似文献   
55.
A procedure has been developed for the synthesis of silica-supported polymerization initiators, which includes chemisorption of (3-aminopropyl)triethoxysilane, hydrolysis of the alkoxy groups, and chemisorption of 4,4′-azobis(4-cyanopentanoic acid). It has been found that the reaction of 4,4′-azobis(4-cyanopentanoic acid) with immobilized amino groups in the presence of N,N′-dicyclohexylcarbodiimide involves only one functional group in the former. The effect of the solid support porosity on the composition of organosilica obtained by surface-initiated radical polymerization of acrylic acid has been studied. The best yield of grafted polyacrylic acid is obtained on aerosilogel with large mesopores in combinations with developed surface. The dependence of the impedance of polyacrylic acid-modified aerosilogel on the relative air humidity has been studied, and the possibility of using this material in humidity sensors has been shown.  相似文献   
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The sensitivity of chemical sensors depends on the number of receptors on the surface; hence, an important role is played by the accessible support surface. Films based on silica mesoporous mesophase materials feature the highest specific surface area for silica materials, and their walls can be modified by various functional groups. In this paper, we propose to use mesoporous mesophase films as supports of sensitive elements for Cr3+ ions.  相似文献   
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The reaction of 2-amino-2-(trichloromethyl)tetrahydro-4-pyrone-5-spirocyclohexane with ethylenediamine afforded 6-amino-2,3-dihydro-4-pyrone-3-spirocyclohexane, whereas 2-amino-5,5-dimethyl-2-(trichloromethyl)tetrahydro-4-pyrone gave 2-(3-hydroxy-2,2-dimethylpropionylmethylene)imidazolidine in low yield.  相似文献   
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