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31.
Tarasevich Yu. I. Bondarenko S. V. Zhukova A. I. 《Theoretical and Experimental Chemistry》2004,40(2):125-129
We have used gas chromatography to study the interaction of water and methanol molecules with active hydrophilic centers on the surface of thermally expanded graphite and graphitized thermal carbon black. We have determined the concentration of carboxyl and phenol hydroxyl groups on the surface of the sorbents and the heats of adsorption for adsorption of the studied substances on these groups. We have shown that water molecules are adsorbed as clusters on the hydrophilic centers of the studied sorbents at very low relative pressures, with n = 2 molecules in the cluster. 相似文献
32.
V. V. Kuznetsov Z. V. Bondarenko T. V. Pshenichkina N. V. Morozova V. N. Kudryavtsev 《Russian Journal of Electrochemistry》2007,43(3):349-354
Kinetics of processes of electrochemical production of a cobalt-molybdenum alloy out of an ammonia-citrate electrolyte is studied. The electrolyte’s composition is similar to that used for depositing a nickel-molybdenum alloy. It is established that the cobalt-molybdenum alloy undergoes deposition at smaller values of pH (5.0–6.0) than the nickel-molybdenum alloy (7.0–9.0). The current efficiency for the cobalt-molybdenum alloy is substantially dependent on the electrolyte pH, whereas the chemical composition of the obtained deposits is practically independent of the electrolyte pH in the pH interval 5.0–8.0 at current densities of 0.025 to 0.100 A cm?2. On the other hand, a change in the electrolyte pH produces a considerable effect on the morphology of the obtained deposits. At large values of pH (pH 8.0), one can obtain a powder-like deposit of the cobalt-molybdenum alloy with a small value of the current efficiency. The deposits that are obtained in the pH region 5.0–6.0 have some cracks, with the number of cracks increasing with the electrolyte pH. 相似文献
33.
The gas-chromatographic method is used to study the interaction of water and methanol molecules with active hydrophilic centres
existing at the surface of thermally exfoliated graphite and graphitized thermal carbon black. The concentration of carboxyl
and phenol hydroxyl groups at the surface of these sorbents is determined, and heats of adsorption of the studied molecules
are shown to be
and 28−25 kJ/mol, respectively. It is also shown that adsorption of water at the hydrophilic centres at lowest relative pressure
values takes place with formation of clusters consisting of n = 2 water molecules. 相似文献
34.
With excess acyl halide 1-methyl-3-acyl-2-(1-methyl-2-benzimidazolyl)-4-benzimidazoline is converted to an unstable 1-methyl-3-acyl-2-(1-methyl-3-acyl-4-benzimidazolin-2-yl)benzimidazolium chloride, which undergoes intramolecular redox cleavage with the formation of 1,1-dimethyl-2,2-dibenzimidazolyl and an aldehyde and dissociates at the C-C bond that connects the benzimidazolium and benzimidazoline fragments into a carbene yield and a 1-methyl-3-acylbenzimidazolium chloride.See [1] for communication 1.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 339–342, March, 1987. 相似文献
35.
K. L. Makovetskii V. A. Yakovlev T. G. Golenko G. N. Bondarenko 《Polymer Science Series B》2006,48(2):61-65
It was shown that branches can be incorporated into linear chains of cis-1,4-polybutadiene produced in the presence of neodymium catalysts. Branched polymers were prepared through the copolymerization of butadiene and a low-molecular-mass polybutadiene macromonomer containing a system of conjugated C=C bonds at chain ends. The incorporation of macromonomer units into the polymer chain was confirmed by the IR spectroscopic analysis of macromonomer-perdeuterobutadiene copolymers. 相似文献
36.
It has been shown that when a mixture of starch with sodium hydroxide and monochloroacetic acid is irradiated, the carboxymethylstarch (CMS) obtained consists of fractions with high levels of carboxymethyl groups and fractions with a predominant content of carbonyl groups, and when this mixture is subjected to mechanical treatment a far-reaching rearrangement of the structure of the starch takes place with its homogeneous interaction with the reagents to form CMS.Institute of Physical Organic Chemistry, Academy of Sciences of the Belorussian SSR, Minsk. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 691–695, November–December, 1984. 相似文献
37.
38.
E. Yu. Mironova M. M. Ermilova M. N. Efimov L. M. Zemtsov N. V. Orekhova G. P. Karpacheva G. N. Bondarenko N. A. Zhilyaeva D. N. Muraviev A. B. Yaroslavtsev 《Russian Chemical Bulletin》2013,62(11):2317-2321
Physicochemical properties and catalytic performance of detonation nanodiamonds were studied. Original samples of nanodiamonds and nanodiamonds modified by hydrogen, oxygen, and nitric acid with hydrogen peroxide and infrared-treated were investigated. The catalyst structure and morphology were examined by transmission electron microscopy and IR spectroscopy. All the investigated catalysts were active in the steam reforming of ethanol. The correlation of catalytic properties with composition and structure of the described systems is discussed. The specific surface area of nanodiamonds is changed insignificantly upon modification. 相似文献
39.
40.