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201.
A. S. Fadeev G. P. Yampol'skaya V. M. Rudoy S. M. Levachev V. N. Izmailova 《Colloid Journal》2003,65(4):500-507
Properties of the monolayers of collagen isolated from the sclera of pig's eye are studied at the air–water interface with increasing tert-butanol or n-hexanol concentrations in a subphase. In the case of aqueous n-hexanol solutions, its adsorption on the subphase surface results in the formation of mixed monolayer whose properties depend on n-hexanol concentration in the subphase and the ratio between the number of alcohol and collagen molecules in the monolayer. At higher n-hexanol surface concentration, the phase separation of the monolayer into the domains of the condensed phase of alcohol and fibrous collagen occurs. A decrease in water activity in the presence of tert-butanol leads to a drastic reduction of collagen surface activity. This effect can be explained by both the constrained collagen spreading on the surface of tert-BuOH solutions and adsorption of alcohol molecules on collagen resulting in macromolecule hydrophilization. Alcohol critical concentrations are disclosed above which collagen monolayers are not formed. 相似文献
202.
CaC2O4真空热分解中,第一阶段生成的CO中47%歧化成CO2和C;第二阶段生成的CO与第一阶段生成的C发生气化反应,发生反应的比例随样品量增加而增大。用CaCO3标定CO后再用CaC2O4标定CO可以排除这些干扰。本文提出了一个对任意气体标定的方法。 相似文献
203.
B. S. Fedorov A. N. Utienyshev A. A. Ghidaspov E. V. Kachanovskaya V. V. Bakharev M. A. Fadeev 《Chemistry of Heterocyclic Compounds》2005,41(4):496-502
A new heterocyclic compound, 3-methyl-5-trinitromethyltetrazolo[1,5-a]-1,3,5-triazin-7-one, was synthesized by the reaction of methyl iodide and the silver salt of 5-trinitromethyltetrazolo[1,5-a]-1,3,5-triazin-7-one. An X-ray diffraction structural analysis of this product was carried out and feasibility was demonstrated for the nucleophilic substitution of the trinitromethyl group in this compound by the action of phenol, phenol derivatives, and thiophenol.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 582–588, April, 2005. 相似文献
204.
Homotopic method has been used to analyze the kinetic model of three-stageCO oxidation on two nonuniform surface patches conjugated byCO
ads spillover. The diagrams of steady states depending onP(CO) at various temperatures have been built.CO
ads spillover from one patch to another changes substantially the bifurcation picture of the steady states. 相似文献
205.
V. V. Avdonin E. P. Kirpichev Yu. I. Rubtsov M. A. Fadeev G. V. Oreshko L. T. Eremenko 《Russian Chemical Bulletin》1991,40(11):2189-2193
Fluorination of bis(2-fluoro-2,2-dinitroethyl) and bis(2,2,2-trinitroethyl) thionocarbonates by elemental fluorine gave bis(2-fluoro-2,2-dinitroethyl) and bis(2,2,2-trinitroethyl) difluoroformals. The reaction of 2,2,2-trinitroethyl nitrate with 2-fluoro-2,2-dinitroethyl chloromethyl ether gave 2-fluoro-2,2-dinitroethyl 2,2,2-trinitroethyl formal. The standard heats of combustion and formation of the synthesized formals were determined by combustion in a calorimetric bomb. Increments of substitution of the trinitromethyl group by the fluorodinitromethyl group and of the H atom by F in the methylene group for formals were calculated and recommended for rough calculations. It was shown that it is possible to evaluate Hf0 of the formals by the method of increments and group contributions.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2513–2517, November, 1991. 相似文献
206.
S. I. Fadeev V. A. Likhoshvai D. N. Shtokalo 《Journal of Applied and Industrial Mathematics》2007,1(2):178-189
The results are presented of studying a mathematical model of linear biomolecular synthesis which accounts for the reversibility of attaching a monomer to a growing molecule and some spontaneous termination of the synthesis. A previous model of a synthesis ignored the influence of reversibility and sinks. It is shown that if the rate of the monomer attachment (the direct process) exceeds the rate of the monomer removal (the reverse process) then the passage to the limit model with infinitely many stages leads to a delay differential equation. For any other ratios of the rates, the solution reaches a stationary state. 相似文献
207.
S. I. Fadeev A. B. Shigarov V. A. Kirillov N. A. Kuzin 《Journal of Applied and Industrial Mathematics》2008,2(3):329-340
The results are presented of the numerical study of a mathematical model in the form of a nonlinear boundary value problem describing the stationary regimes in a catalytic fuel processor. We study a two-dimensional model for the endoblock, with the longitudinal heat and mass transfer by the gas and the transversal heat conductivity along the catalyst in the two-temperature approximation. For the exochannel, a model is considered with the longitudinal heat and mass transfer by the gas flow and the longitudinal heat transfer along the catalytic wall. These two blocks are related to each other through the equality of the temperature and heat flux on the boundary. The results obtained are in good agreement with experimental data. 相似文献
208.
The true molecular photophysical parameters’ values of tryptophan residues in single-tryptophan-containing and two-tryptophan-containing proteins (by the example of human serum albumin and bovine serum albumin) have been determined for the first time with the use of the authors’ suggested algorithm. The algorthm is based on the simultaneous use of nonlinear and kinetic-laser fluorimetry. The obtained result opens up new approaches in the monitoring of living systems and other objects, containing single fluorophores and localized pairs of fluorophores. 相似文献
209.
The inverse scattering problem at a fixed energy for a complex-valued potential is solved in the WKB approximation. The method is used to reconstruct the optical potential for elastic 16O + 16O scattering at E lab = 350 MeV. The stability of the solution against small changes in the scattering matrix is studied. 相似文献
210.
T M Roshchin N K Shonia A A Kazmina K B Gurevich A Y Fadeev 《Journal of chromatography. A》2001,931(1-2):119-127
We report the synthesis and adsorption study of the lyophobic porous silicas. Four adsorbents were prepared and tested: (1) octyl-silica, (2) hexadecyl-silica, (3) bis(trimethylsiloxy)-silica, and (4) oligo(dimethylsiloxane)-silica. Octyl- and hexadecyl-silicas were prepared via the reaction of silica with (CH3)2NSi(CH3)2CnH(2n+1) (n=8 and 16), the reactions were carried under the optimized conditions yielding high bonding densities of alkyl groups approximately 2.9-3.0 groups/nm2 and highly uniform non-polar adsorbents. Bis(trimethylsiloxy)-silica was prepared via the reaction silica with ClSi(CH3)2(CH2)10Si(CH3)[OSi(CH3)3]2. Oligo(dimethylsiloxane)-silica was prepared via the reaction of silica with ClSi(CH3)2-[OSi(CH3)2]2-Cl. Adsorption of small organic compounds (n-alkanes, alkylbenzene, benzene, diethyl ether) was investigated using two methods, classical static adsorption and gas chromatography. Thermodynamic parameters (heat, Gibbs energy, and entropy) of the adsorption of organic compounds were studied as a function of the nature of adsorbate and of the nature of the bonded layer as well. The results obtained suggest penetration of the adsorbate molecules into the bonded layer and the importance of this process in the retention mechanism in gas chromatography. Energy of the dispersion interactions with the surface decreases in the following order: n-C16H33(CH3)2Si- > n-C8H17(CH3)2Si- > [(CH3)3SiO]2Si(CH3)-(CH2)10(CH3)2Si- > -[[(CH3)2SiO]2]x-(CH3)2Si-. Energy of the electrostatic and hydrogen bonding interactions with the surface, as assessed from the adsorption of benzene and diethyl ether molecules, decreases in the opposite direction, indicating that alkyl-silicas are less polar adsorbents than methylsiloxy-silicas. 相似文献