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11.
V. E. Tarabanko V. N. Sidelnikov I. V. Kozhevnikov 《Reaction Kinetics and Catalysis Letters》1982,21(1-2):109-114
It has been established that in the oxidation of diethyl sulfide by18O2 in CH3C16O2H–H2
16O solution at 369 K catalyzed by heteropoly acids, sulfoxide and sulfone with 44–54%18O enrichment are formed. The process is accompanied by isotope exchange of molecular oxygen.
, 18O2 CH3C16O2H–H2 16O 369 18O 44–54%, .相似文献
12.
Kozhevnikov I. S. Kovalev V. L. Rusinov O. N. Chupakhin 《Chemistry of Heterocyclic Compounds》2001,37(9):1136-1140
3-R-6-Phenyl-1,2,4-triazine 4-oxides react with cyclic -diketones (dimethylbarbituric acid, dimedone, and indan) in both acidic (substrate activation) and basic conditions (nucleophile activation) with formation of H-adducts, intermediates in the nucleophilic substitution of hydrogen (SN
H) in 3-R-5-Nu-4-hydroxy-6-phenyl-4,5-dihydro-1,2,4-triazines. Oxidative aromatisation of these intermediates or auto-aromatisation of acylated (benzoyl chloride) at the NOH -adducts with elimination of benzoic acid gave the corresponding substituted 1,2,4-triazine 4-oxides or 1,2,4-triazines. 相似文献
13.
G. U. Mennenga A. I. Rudenkov K. I. Matveev I. V. Kozhevnikov 《Reaction Kinetics and Catalysis Letters》1976,5(4):401-406
Oxidative coupling of alkylbenzenes (benzene, toluene, o-xylene, durene) is shown to proceed in the presence of palladium salts and heteropolyacids under the action of oxygen with a high yield of diaryls. The addition of mercury salts and variation of the solvent affect the reaction rate and isomer composition of the products.
, (, , -, ) . .相似文献
14.
V. E. Tarabanko I. V. Kozhevnikov K. I. Matveev 《Reaction Kinetics and Catalysis Letters》1978,8(1):77-79
Oxidative coupling of thiophene and 2-methylfuran to the corresponding dihetaryls in DMFA medium occurs in the presence of the homogeneous catalytic system Pd(II)-molybdovanodophosphoric heteropolyacid (HPA). The data obtained show that HPA may act as a reversible oxidant in polar aprotic media.
, Pd(II)- 2- . , .相似文献
15.
This paper presents the results of calculation of adhesion for adhesive compounds based on a ureaformaldehyde oligomer KFN-66 modified with alcohols at a stage of mixing components with respect to production of wood-based panels for construction purposes. The optimum flow rate and type of the modifier for ensuring maximum work of adhesion are found. 相似文献
16.
Experimental results of synthesis and investigation of the efficiency of a cationic aminopolymer resin are presented. The monomers are characterized, the synthesis conditions are considered, and the technical characteristics of the resin are given. It is shown that the resin facilitates the acceleration of dehydration of repulped stock, significantly reduces the cationic need, increasing the retention of anionic contaminations, and decreases the content of suspended substances in recycled water. The data on pilot tests of the resin are presented that demonstrate its high efficiency. 相似文献
17.
Sulyaeva V. S. Gatapova E. Ya. Kozhevnikov A. K. Rogilo D. I. Saraev A. A. Yushina I. V. Khomyakov M. N. Shapovalova A. A. Shayapov V. R. Bhaskar N. Tu R. Kosinova M. L. 《Journal of Structural Chemistry》2021,62(8):1309-1324
Journal of Structural Chemistry - We report a comprehensive study of the effect of the chemical structure of boron carbonitride films on the variability of their functional characteristics. The... 相似文献
18.
A. Yu. Kozhevnikov S. L. Ul’yanovskaya M. P. Semushina S. A. Pokryshkin A. V. Ladesov I. I. Pikovskoi D. S. Kosyakov 《Russian Journal of Applied Chemistry》2017,90(4):516-521
Application of the oxidative modification of sulfate kraft lignin with sodium periodate under mild conditions is suggested in order to obtain a sorbent for detoxication of spillage places of rocket fuels based on 1,1-dimethylhydrazine and to purify wastewaters containing this compound. It was found that processing with the periodate at a temperature of 55°C for 20 h results in a more than twofold increase in the content of carbonyl and quinone groups in a lignin preparation and a rise in its polydispersity due to the appearance of a macromolecular condensed fraction and a threefold increase in the sorption capacity for 1,1-dimethylhydrazine. The sorbent can bind 6.7% of 1,1-dimethylhydrazine and substantially surpasses in this parameter other lignin-based sorbents. It was shown that the firm chemical binding of hydrazines hinders desorption of the highly toxic rocket propellant and products of its oxidative transformation from the surface of lignin both into solution and into the vapor phase, thereby providing safe handling of the spent sorbent. 相似文献
19.
Veksler B. A. Lemelle A. Kozhevnikov I. S. Akchurin G. G. Meglinski I. V. 《Optics and Spectroscopy》2011,110(3):483-488
We consider the possibility of using gold nanoparticles to improve the image contrast of biotissue structures in reflection
confocal laser microscopy. We present the results of experimental studies using gold nanospheres with a diameter of 60 nm
compared to osmotically active immersion contrast agents based on glycerol. 相似文献
20.
S. B. Venig R. K. Chernova V. G. Serzhantov V. P. Splyukhin M. A. Perespelova E. I. Selifonova G. N. Naumova A. M. Zakharevich A. A. Selifonov I. O. Kozhevnikov N. N. Scherbakova 《Moscow University Chemistry Bulletin》2017,72(5):245-250
A technique for preparing enriched glauconite on the basis of a natural mineral from the Beloozyorskoe field of Saratov oblast has been developed. The results of a study of the chemical composition, surface structure, and certain physicochemical properties of the samples of the sorbent are presented. The sorption of ambroxol hydrochloride ions from aqueous solutions has been studied using natural and enriched glauconite. The sorption isotherms, are approximated by the Langmuir equation, have been obtained, and the values of the maximum sorptive capacities have been calculated. Based on the obtained data, conclusions have been drawn on using the studied natural mineral sorbents to extract the above-mentioned substance from aqueous solutions. 相似文献