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981.
V. V. Vysotskii O. Ya. Uryupina I. N. Senchikhin V. I. Roldughin 《Colloid Journal》2013,75(6):634-641
The conductivity of ring-shaped deposits formed at the periphery of evaporating droplets of silver nanoparticle colloidal solutions has been studied. The dependence of the resistance of the ring-shaped deposits on nanoparticle size has been shown to exhibit a percolation transition. The specific conductivity of the deposits has been estimated in relation to their geometric shapes. The conductivity has been established to nonmonotonically depend on nanoparticle sizes. It has been noted that, in rather strong fields, the conductivity of the composite layers dramatically increases after some induction period. The X-ray spectra of silver have been revealed to alter for samples the conductivity of which has increased under the action of an external electric field. 相似文献
982.
An NMR-relaxation study of the effect of albumin on aggregation of magnetic iron oxide nanoparticles
Ya. Yu. Marchenko B. P. Nikolaev A. N. Shishkin L. Yu. Yakovleva 《Colloid Journal》2013,75(2):185-190
The dependence of the aggregation of magnetic iron oxide nanoparticles in aqueous suspensions under the action of human serum albumin is analyzed based on the data of proton magnetic relaxation. It is shown that albumin adsorption on magnetic nanoparticles gives rise to the formation of a protein corona and clusters of magnetic nanoparticles, decreasing the aggregation stability of the suspension in a 7.1-T magnetic field. Clustering of magnetic iron oxide nanoparticles enhances the relaxation efficiency of magnetic suspensions during NMR measurements. 相似文献
983.
A reaction of aliphatic 1,2-hydroxylamino oximes bearing the hydroxylamino group at the secondary carbon atom with aromatic and heteroaromatic aldehydes in acetic acid leads to the corresponding 1-hydroxy-2-aryl(hetaryl)-4,5-dialkylimidazoles in high yields. α-Aryl(hetaryl)-nitrones initially formed by the condensation of 1,2-hydroxylamino oximes with aldehydes are quantitatively converted to the corresponding imidazoles. 相似文献
984.
E. V. Shchegol’kov Ya. V. Burgart V. I. Saloutin O. N. Chupakhin 《Russian Chemical Bulletin》2013,62(1):220-222
Fluorinated 2-amino-5-phenyl-1,3,4-thiadiazines were obtained for the first time. A study of their tautomeric structures revealed that trifluoromethyl-containing 1,3,4-thiadiazines exist as the 4H-tautomer in both solutions and the solid state, while their monofluoroaryl analogs exist as the 6H-tautomer. 相似文献
985.
Tetrakis(di-tert-butylmethylsilyl)tetragermacyclobutadiene]ruthenium tricarbonyl [η4-(But 2MeSi)4Ge4]Ru(CO)3 is synthesized. This analogue of well-known cyclobutadiene transition metal complexes bears a tetragermacyclobutadiene derivative as ligand. The structure and spectroscopic parameters of the complex are compared with those of its iron-containing analogue [η4-(But 2MeSi)4Ge4]Fe(CO)3. Based on experimental data and results of quantum chemical calculations, it is shown that the π-donating ability of ligands increases upon replacement of carbon atoms in the cyclobutadiene moiety by silicon or germanium atoms, tetrasilacyclobutadiene and tetragermacyclobutadiene being comparable in π-donating activity. 相似文献
986.
Ya. R. Arustamov P. T. Sukhanov A. S. Gubin Yu. S. Peregudov E. V. Churilina G. V. Shatalov E. V. Koroleva 《Russian Journal of Applied Chemistry》2013,86(8):1292-1297
New cross-linked copolymers based on N-vinylpyrrolidone and N-vinylcaprolactam were proposed for preconcentration of carbaryl and naphthols from aqueous media. The influence of pH, nature of salting-out agent, surfactant, and temperature on the recovery of the analytes was examined. The most efficient sorption systems for recovery of carbaryl and naphthols from aqueous solutions were developed. 相似文献
987.
E. V. Shchegol’kov A. E. Ivanova Ya. V. Burgart V. I. Saloutin O. N. Chupakhin 《Russian Journal of Organic Chemistry》2013,49(3):417-420
Alkylation of 2-(trifluoromethyl)-1H-benzimidazole with 4-bromobutyl acetate gave 4-[2-(trifluoromethyl)-1H-benzimidazol-1-yl]butyl acetate which was deacylated by the action of hydrogen chloride in anhydrous ethanol. 4-[2-(Trifluoromethyl)-1H-benzimidazol-1-yl]butan-1-ol thus formed showed a moderate tuberculostatic activity. Alkylation of the title compound with chloromethyloxirane afforded a mixture of 1-chloro-3-[2-(trifluoromethyl)-1H-benzimidazol-1-yl]-propan-2-ol and 1-(oxiran-2-ylmethyl)-2-trifluoromethyl-1H-benzimidazole. A new procedure was proposed for the synthesis of 2-[(2-trifluoromethyl-1Hbenzimidazol-1-yl)methoxy]ethyl acetate. 相似文献
988.
Ya. V. Veremeichik P. V. Merabov A. V. Chuiko O. A. Lodochnikova V. V. Plemenkov 《Russian Journal of Organic Chemistry》2013,49(11):1605-1609
From substituted N-sulfinylanilines acting as dienes in the Diels-Alder reaction with norbornadiene S-oxides of benzo-ortho-thiazines were obtained, which were oxidized into the corresponding S,S-dioxides belonging to the class of hybrid thiazinesulfonamide compounds. 相似文献
989.
Kh. M. Alimardanov N. I. Garibov M. Ya. Abdullaeva O. A. Sadygov A. D. Kuliev E. G. Ismailov 《Russian Journal of General Chemistry》2013,83(1):63-71
Oxidation of alicyclic unsaturated hydrocarbons (4-vinylcyclohexene, 5-vinylnorbornene, 5-cyclohexenylnorbornene, and 5-vinylbicyclooctene) with 30% hydrogen peroxide solutions and percarbamide is studied. Reaction was carried out at 40–70°C in the presence of heterogenized peroxocomplex compounds of molybdenum and tungsten formed “in situ” in the reaction of metal oxohalides with H3PO4, nano-dimensional particles of carbon material, and hydrogen peroxide. Main oxidation products of alicyclic diene hydro-carbons are the corresponding unsaturated epoxides and diols. Depending on the reaction condition their ratio varies in a wide range. 相似文献
990.
Compounds widely known as 1,4-bis(alkylamino)-9,10-anthraquinones are in fact neither individual substances nor substituted 9,10-anthraquinones but equilibrium mixtures of tautomers. Their aminoimine tautomeric transformations follow the sequence 4,9-bis(alkylamino)-1,10-anthraquinones ? 9-alkylamino-4-(alkylimino)-10-hydroxy-1,4-dihydroanthracen-1-ones ? N 1,N 10-dialkyl-4,9-dihydroxy-1,10-dihydroanthracene-1,10-diimines. 相似文献