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111.
Photolytic decomposition of the complex [Co(NH3)5(H2O)](ClO4)3 under the action of a laser with a wavelength of 355 nm, which is resonant in energy to the energy of the (1 A 1g 1 T 2g ) d–d transition, was studied. Decomposition of the complex is accompanied by a release of ammonia with its subsequent oxidation to nitrogen oxides and by partial cobalt reduction with the formation of the mixed cobalt(II, III) oxide Co3O4.  相似文献   
112.
It was demonstrated experimentally that the spatial separation of two processes of chemical vapor deposition, one of which provides synthesis of filler (MoS2) nanoparticles and the other yields the matrix (SiO2) of the nanocomposite coating, performed ina common reactor, enables an independent control over two process rates and makes it possible to widely vary the composition of the films deposited in this way. The deposition was performed in a double-zone vertical tubular quartz reactor. Molybdenum disulfide particles were produced by pyrolysis of aerosols of ammonium thiomolybdate solutions in dimethylformamide in the upper zone of the reactor, and the plasma-chemical deposition of a nanocomposite coating occurred in the lower zone into which MoS2 nanoparticles were transported by the gas flow and tetraethoxysilane was delivered. It was shown that the nanocomposite coatings composed of molybdenum disulfide (filler) and silicon oxide (matrix) possess improve the antifriction properties as compared with the matrix (SiO2 layers), these properties being determined by the relative amounts of MoS2 nanoparticles in the layer and by their average size.  相似文献   
113.
The dependence of the physicomechanical properties of epoxy nanocomposites subjected to heat and humidity aging on the type of covalently functionalized carbon nanotubes and on the uniformity of their distribution in the epoxy matrix was studied. Two types of carbon nanotubes were used: those modified with carboxy and amide groups. The elastic modulus, bending deflection, and ultimate bending strength for the initial epoxy nanocomposites with carbon nanotubes and for those subjected to heat and humidity aging were determined. The epoxy binders modified with carboxylated carbon nanotubes are more resistant to the action of aging factors. The presence of aggregates of carboxylated carbon nanotubes in the epoxy matrix positively influences the preservation of physicomechanical properties of the composite subjected to heat and humidity aging. Microscopic examination revealed structural features of the epoxy nanocomposite and their effect on the resistance of the composite to the heat and humidity aging.  相似文献   
114.
Potentialities of the method of electrophoretic deposition of thin-film coatings based on micrometer powders of multidoped barium cerate BaCe0.8Sm0.19Cu0.01O3–δ (BCSCuO) and BaCe0.89Gd0.1Cu0.01O3–δ (BCGCuO) were considered. Micrometer powders of BCSCuO and BCGCuO were produced by the methods of solid-phase and citrate-nitrate syntheses, respectively. The dispersity, fraction composition, and electrokinetic potential of nonaqueous suspensions of these powders and the electrokinetic parameters of the electrophoretic deposition process were examined. An ultrasonic treatment and ultracentrifugation produced aggregatively stable suspensions of BCGCuO and BCSCuO micrometer particles in a mixed (70/30 vol %) isopropanol–acetyl acetone medium. These suspensions are characterized by high positive values of the zeta potential (+24 and +28 mV, respectively). Thin film coatings of the electrolyte materials BCSCuO and BCGCuO, which are of interest for the technology of medium-temperature solid-oxide fuel cells, were produced by the electrophoretic deposition onto a dense model cathode.  相似文献   
115.
Reactions of aromatic aldehyde, 2-aminoprop-1-ene-1,1,3-tricarbonitrile and cyclic enhydrazinoketones led to the formation of N-substituted 5-aryl-2,4-diamino-6-oxo-5,6,7,8,9,10-hexahydrobenzo[b][1,8]- naphthyridine-3-carbonitriles  相似文献   
116.
4-(2-Hydroxyphenyl)-1,3,5-triazin-2-ylcyanamides reacted with sodium azide to give N-(tetrazol-5-yl)-1,3,5-triazin-2-amines, and their reaction with allyl bromide afforded allyl(1,3,5-triazin-2-yl)cyanamides. Acetylation of 4-(2-hydroxyphenyl)-1,3,5-triazin-2-amines involved only the amino group with formation of diacetylamino derivatives, whereas the phenolic hydroxy group remained intact. The reaction of triazinamines with 2,5-dimethoxytetrahydrofuran in the presence of P2O5 gave pyrrolyl-substituted triazines.  相似文献   
117.
Russian Journal of Organic Chemistry - Crotone condensation of allobetulone with fluorine-containing benzaldehydes afforded new α,β-unsaturated ketones of lupane series. Their...  相似文献   
118.
Russian Journal of Organic Chemistry - Acylation of 9-(2-ethylhexyl)carbazole with acetyl bromide in the presence of tin(IV) chloride gave 3-acetyl- and 3,6-diacetyl-9-(2-ethylhexyl)carbazoles...  相似文献   
119.
Russian Journal of Organic Chemistry - The alkylation of 6-amino-2-thiouracil with allyl, methallyl, and propargyl halides in the presence of bases gave 2-[allyl(methallyl,...  相似文献   
120.
The dynamic structure of styrene has been studied with the goal of obtaining detailed information on the internal rotation parameters. A potential energy surface has been constructed for the rotation of the vinyl group about the single bond in terms of the second-order Møller–Plesset perturbation theory with aug-cc-pvtz basis functions, and conformational dependences of n J HH have been calculated at the FPT DFT (B3LYP) level of theory with basis functions of the same type. The vibration-averaged coupling constants have been compared with the experimental values reliably determined in this work. A high efficiency of the proposed dynamic model for structural studies of organic molecules with ultrafast internal rotation dynamics has been demonstrated.  相似文献   
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