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Tovbin Yu.K.,Karpov Research Physicochemical Institute | Titov S.V.,Karpov Research Physicochemical Institute
Russian Journal of Physical Chemistry A | Year: 2013

We investigate the effect of restricting the area of planes of microcrystals and equilibrium density fluctuations in components of binary mixtures on partial isotherms of the adsorption of binary mixtures of molecules and the rate of a surface reaction of the Langmuir-Hinshelwood type. Adsorption of components of mixture is considered in a large canonical assembly, and the rate of an elementary step is calculated in kinetic regime. The value of a section of the surface on a plane contains a number of adsorption centers in the range of 10 to 105. The effect of the structure of a heterogeneous surface on the rate of the considered reaction is studied. The effect of the density fluctuations of adsorbed molecules on partial adsorption isotherms and fluctuations in the rate of reaction on heterogeneous surfaces is discussed. It is shown that the greatest effect of density fluctuations on the rate of a step is observed at low fillings of each plane of a particle and at the almost complete filling of a plane. © 2013 Pleiades Publishing, Ltd.

Timashev S.F.,Karpov Research Physicochemical Institute | Solov'Eva A.B.,RAS Semenov Institute of Chemical Physics | Buslaeva E.Yu.,RAS Kurnakov Institute of General and Inorganic Chemistry | Gubin S.P.,RAS Kurnakov Institute of General and Inorganic Chemistry
Russian Journal of Physical Chemistry A | Year: 2013

The possibility of obtaining concerted mechanisms of chemical activation in supercritical fluids (SCFs) with the formation of a multicenter general transition state that includes a group of reagent atoms in which the subsequent breaking of chemical bonds and the formation of new chemical bonds start and proceed simultaneously is discussed. Two processes are considered that can occur only in SCF media: the reduction of anthracene in an isopropyl alcohol SCF and the impregnation of the photochromic compound spiroanthrooxazine (SAO) in a polycarbonate matrix in SC CO2 accompanied by an irreversible conformational rearrangement of the SAO structure. Concepts of the possible dependence of the concerted mechanism of the considered processes on the intertwining or entanglement of electron subsystems in forming multicenter transition states are developed. The decisive role of the electromagnetic component of a physical vacuum in obtaining a high degree of correlation in systems of entangled electrons is discussed. © 2013 Pleiades Publishing, Ltd.

Boyko V.M.,Karpov Research Physicochemical Institute | Verevkin S.S.,Karpov Research Physicochemical Institute | Kolin N.G.,Karpov Research Physicochemical Institute | Korulin A.V.,Karpov Research Physicochemical Institute | And 3 more authors.
Semiconductors | Year: 2011

Effect of irradiation with high reactor-neutron fluences (Φ = 1.5 × 1017-8 × 1019 cm-2) and subsequent heat treatments in the temperature range 100-1000°C on the electrical properties and lattice constant of epitaxial GaN layers grown on an Al2O3 substrate is considered. It is shown that, with the neutron fluence increasing to (1-2) × 1018 cm-2, the resistivity of the material grows to values of about 1010 Ω cm because of the formation of radiation defects, and, with the fluence raised further, the resistivity passes through a maximum and then decreases to 2 × 106 Ω cm at 300 K, which is accounted for by the appearance of a hopping conductivity via deep defects in the overlapping outer parts of disordered regions. With the neutron fluence raised to 8 × 1019 cm-2, the lattice constant c increases by 0.38% at a nearly unchanged parameter a. Heat treatment of irradiated samples at temperatures as high as 1000°C does not fully restore the lattice constant and the electrical parameters of the material. © 2011 Pleiades Publishing, Ltd.

Obvintseva L.A.,Karpov Research Physicochemical Institute | Dmitrieva M.P.,Karpov Research Physicochemical Institute | Klimuk A.I.,Karpov Research Physicochemical Institute | Shepelev A.D.,Karpov Research Physicochemical Institute | And 4 more authors.
Russian Journal of Applied Chemistry | Year: 2010

The action of ozone in high (1.3 vol %) concentrations on polysulfone microfibers was studied by iodometric titration, IR spectroscopy, and electron microscopy. © 2010 Pleiades Publishing, Ltd.

Obvintseva L.A.,Karpov Research Physicochemical Institute | Zhernikov K.V.,Karpov Research Physicochemical Institute | Sukhareva I.P.,Karpov Research Physicochemical Institute | Shepelev A.D.,Karpov Research Physicochemical Institute | And 3 more authors.
Russian Journal of Applied Chemistry | Year: 2010

Interaction of ozone with microfibrous polymeric filtering materials based on polystyrene, polysulfone, cellulose diacetate, chlorinated polyvinyl chloride, and tetrafluoroethylene-vinylidene difluoride copolymer was studied. The concentration of ozone that passed through these materials was determined with semiconductor sensors. Filtering materials based on polystyrene and polysulfone are of interest for use as respirator materials. © 2010 Pleiades Publishing, Ltd.

Ogorodnikov B.I.,Karpov Research Physicochemical Institute
Russian Meteorology and Hydrology | Year: 2011

A meteorological situation is under consideration during a dust storm observed on September 5-7, 1992 over the Ukraine and Belarus territory contaminated by radionuclide products after the Chernobyl accident. The highest average wind speed in Chernobyl and Pripyat was 10-12 m/s, wind gusts reached 20 m/s. It was found that the radioactive aerosol concentration in the zone of alienation of the Chernobyl NPP increased by one or two orders of magnitude. The transfer of radioactive dust particles to the Vilnius outskirts is recorded. © 2011 Allerton Press, Inc.

Ostrovsky G.M.,Karpov Research Physicochemical Institute | Lapteva T.V.,Kazan State Technological University | Ziyatdinov N.N.,Kazan State Technological University
Theoretical Foundations of Chemical Engineering | Year: 2014

During the design of engineering systems under the conditions of the partial uncertainty of physical, chemical, and economical information, the determination of a design at which its control system would ensure the performance of all constraints (exactly or with somewhat probability) is an essential problem despite the change of internal and external factors at operation stage. In this paper, one- and two-stage optimization problems with hard and soft constraints have been considered that must be solved during the design of flexible optimal systems. Approaches that enable one to avoid the procedures of multidimensional integration at each iteration of the solution of problems have been suggested. © 2014, Pleiades Publishing, Ltd.

Timashev S.F.,Karpov Research Physicochemical Institute
Russian Journal of General Chemistry | Year: 2011

Inner phenomenological essence was revealed for flicker-noise spec-troscopy (FNS), a methodology for extracting information from multifactor dynamic systems on the basis of primary digital information, which was presented as "pheno-menology of complexity" and "materialization" of Edmund Husserl's phenomenology. The basic FNS equations used for analysis of experimental data were given. At the present time, the FNS method can be used for solving three types of problems: (1) determination of parameters or patterns that characterize the dynamics or structural features of complex systems; (2) identification of precursors of abrupt changes in the state of various complex systems based on a priori information about the system dynamics; and (3) assessment of the flow dynamics in distributed systems based on analysis of dynamic correlations in stochastic signals that are measured simultaneously at different points in space. © 2011 Pleiades Publishing, Ltd.

Lakeev S.G.,Karpov Research Physicochemical Institute | Voeikov V.L.,Moscow State University | Timashev S.F.,Karpov Research Physicochemical Institute
Russian Journal of General Chemistry | Year: 2011

The general problems of information deriving from the oscillation kinetics of Belousov-Zhabotinsky reactions were discussed. The discussion was organized around a particular example of the complex fluctuation dynamics of the Maillard reaction, i.e., a multistage reaction between a carbonylcontaining compound and the nucleophilic amino group of an amino-containing compound at different temperatures, as visualized by chemiluminescence. Flicker-noise spectroscopy served as methodological background of the fluctuation analysis comprising the two main steps: separation of low-frequency components attributed to resonances and their interference, from the source signals and analysis of the remaining chaotic components. Possibility of modeling the chaotic dynamics of fluctuations of the measured dynamic variables in terms of anomalous diffusion was shown. © 2011 Pleiades Publishing, Ltd.

Lukashev R.V.,Karpov Research Physicochemical Institute | Zanaveskin K.L.,Karpov Research Physicochemical Institute | Kuz'min A.G.,Karpov Research Physicochemical Institute
Russian Journal of Applied Chemistry | Year: 2014

The effect of mechanical treatment of γ- Fe2O3 in a planetary ball mill on the physicochemical and sorption properties of the powders obtained was studied. The mechanical treatment in the presence of ethanol allows preparation of single-phase γ- Fe2O3 powders exhibiting high adsorption capacity for Co(II) ions. The sorption characteristics of the mechanically activated γ- Fe2O3 powders depend on the mechanical treatment parameters. The sorbents that take up Co(II) ions from aqueous solutions most efficiently, with the maximal adsorption capacity of up to 0.43 mmol g-1, can be prepared at maximal rotation rates of the mill drum. © Pleiades Publishing, Ltd., 2014.

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