The influence of modifying admixtures on the catalytic properties of the Ni<Subscript>3</Subscript>Al intermetallic compound in the conversion of methane with carbon dioxide

Catalytic systems based on the Ni₃Al intermetallic compound and modified with niobium and chromium were studied in methane reforming with carbon dioxide. The catalysts were prepared under self-propagating high-temperature synthesis conditions. The phase composition of the catalytic systems was studied by X-ray diffraction. The catalytic activity of the samples increased as the concentration of modifying admixtures decreased and was maximum at 2% concentrations of Nb and Cr. The scanning electron microscopy data showed that the catalytic systems experienced substantial structural changes, which caused catalytic activity loss with time.     

Shape of the surface of a vertical liquid bridge between two parallel solid planes taking into account the gravity force for small Bond numbers

A variational formulation has given the problem of the shape of the lateral surface of a small vertical liquid θ bridge between two parallel solid surfaces that take into account the gravity force in the axisymmetric case. An algorithm has been constructed for the iterative solution of the problem for small Bond numbers. The dependence of the number of solutions on the liquid bridge height has been analyzed.     

The Problem of the Shape of a Vertical Liquid Bridge between Convex Surfaces Taking the Gravity Force into Account

Technical Physics - The solution to the problem of the shape of the lateral surface of a vertical 3D catenoidal liquid bridge of small volume between two arbitrary convex solid surfaces in the...     

Spectral Properties and Photochemical Activity of Chalcone Derivatives

A relationship is found between spectral-luminescent and photochemical properties for mono- and disubstituted chalcone derivatives ^R1CO-CH = CHR² [R¹, R² = Ph, 4-FC₆H₄, 4-BrC₆H₄, 2-furyl, 2-thienyl, 4-(PhCONH)C6H4, 4-NH₂C₆H₄, 4-Me₂NC₆H₄].     

Methane conversion with carbon dioxide on nickel aluminides

The catalytic activity of several samples based on nickel aluminides in methane conversion with carbon dioxide was studied. Nickel aluminides were prepared by the method of self-propagating high-temperature synthesis. The Ni₃Al system containing the nickel metal phase exhibited high activity at temperatures above 1073 K. The systems based on Ni₂Al₃ and NiAl only containing intermetallic compound phases were inactive.     

Photosensitization of Conjugated Bischalcone Derivatives. New T-Sensitizers

Photophysical properties and sensitizing activity in the polymerization of conjugated bischalcone and its derivatives of sensitizers of different classes: ketocoumarins, thioxanthenones, aminomethylene derivatives of heterocyclic thioketones, and selenium analogs of the latter, in deaerated solutions of N,N-dimethylacetamide in the presence of reducing agents were studied.     

Fe-Containing Intermetallic Compounds As Catalysts of Methane Conversion with Carbon Dioxide

Systems based on iron and aluminum were studied in methane conversion with carbon dioxide. The systems were prepared by the method of self-propagating high-temperature synthesis. Massive iron did not exhibit noticeable catalytic activity in methane conversion with carbon dioxide. The deactivation of iron-containing intermetallic compounds was shown to occur because of the formation of the FeC and FeO phases, which screened the active centers of the catalyst surface. The suggestion was made that the active center of the dissociative adsorption of methane was the γ-Fe phase, which existed at the working temperature of methane conversion with carbon dioxide.     

Formation of compaction products in methane dry reforming on a Ni-containing catalyst

The formation of compaction products and their morphological features in the process of methane dry reforming on a Ni₃Al catalyst were studied. It was shown that the initial porous structure of a sample was retained in the course of reaction, and the formation of carbon deposits did not decrease the catalytic activity of Ni₃Al over a long period of time.     

Variational problems on the contact of heterogeneous phases

The variational formulation of general problems of capillary surface equilibrium (problems on a drop on a solid surface, drop on the surface of a drop of another liquid, partly faceted capillary surface) is considered. For the problem of a partly faceted capillary surface, the Legendre transformation between the equilibrium form and surface energy density is used.