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A one-pot method was developed for the preparation of composites containing Cu3(BTC)2 and phosphotungstic acid with controllable content of polyoxometallate in the matrix of a coordination polymer. It was shown that increase of the polyoxometallate content of the composite led to complication in the system of pores in the coordination polymer and to reduction of their size. The catalytic properties of the composites in the formation of dimethyl ether from methanol were studied.

4-Hydroxy-/4-oxo tautomerism in the series of 3-substituted 2-methyl-quinolin-4(1H)-ones has been studied by 13C NMR-spectroscopy and quantum-chemical methods in various approximations (restricted Hartree-Fock method, DFT and MP2) for the isolated molecules and for solutions using empirical correction of effects for solvents (PCM COSMO procedure). Substituents that are different in their nature have no significant influence on the value of the chemical shift of carbon in position C4 of the quinolone cycle. The only exception is the carbon shielding associated with the bromine atom in the molecule of 3-bromo-2-methyl-1,4-dihydroquinoline-4-one. Significant deshielding detected in all cases in 13C NMR-spectra of the carbon nuclei in position 4 of the ring is in favour of the existence of all derivatives studied as 4-oxo forms in DMSO-d6 solution. The experimental and calculated values for the chemical shift of carbon in position C4 of 4-oxo and 4-hydroxy isomers differ considerably and can be used as a criterion for assigning quinolin-4 (1H)-ones to a particular tautomeric form.

Catalytic properties of the RhSe2/Ga/H-ZSM-5 system formed upon thermal treatment of a mechanical mixture of rhodium selenochloride Rh2Se9Cl6 and a gallium-containing zeolite Ga/H-ZSM-5 at 300–340°C in a flow of nitrogen were studied in the course of glycerol dehydration in the gas phase. It was shown that the promotion of Ga/H-ZSM-5 with rhodium selenide RhSe2 makes higher the yield of the target product acrolein.

The CuO–CeO 2 –MeO x (Me = Zr, Ti, Mn, Al; x = 1.5–2) solids were tested in the preferential CO oxidation reaction in hydrogen-rich gas mixtures (PROX). We study an effect of a support (MeO x ) the CO conversion and selectivity in the PROX reaction showing that monoclinic zirconia (m-zirconia) with low surface area is the most effective support. The optimal catalyst composition was determined by varying copper and ceria loadings over m-zirconia. XRD and XPS studies indicate that a good catalytic performance of m-zirconia supported copper–ceria catalysts may be attributed to the presence of dispersed Cu-containing species that interact with CeO 2 and ZrO 2 .

The possibility of formation of nanocrystalline Ti-Al-N coatings using the method of ion-plasma deposition is demonstrated. The mechanical and tribotechnical characteristics of the coatings in comparison with TiN coating are studied. Ti-Al-N nanocomposite coatings possess high hardness (35 GPa) and higher wear resistance and lower wear capacity as compared to TiN coating. For a grain size of 12–15 nm the nanostructural Ti-Al-N coating has the following elemental composition: Ti ≈ 60 at %, N ≈ 30 at %, Al ≈ 10 at %. The phase composition of the coating represents the solid solution (Ti, Al)N. For this elemental and phase composition and nanograin size maximal hardness and elasticity modulus of the coating are found.

The gas phase methane oxidative carbonylation was studied in the presence of molecular oxygen over silica materials including their mechanical mixtures with rhodium chalcogen chlorides obtained in non-aqueous inorganic media. The formation of Rh4SCl7, Rh4S9Cl2, Rh4Se5Cl3 and Rh3Se3Cl solids was confirmed by elemental analysis, IR absorption spectroscopy, XPS and X-ray diffraction. Silica, vanadium-, and molybdenum-containing mesoporous molecular sieves have been used as supports. It was found that productivity of oxygenates (methanol, methyl acetate and acetic acid) depends mainly on the method of the catalyst preparation and the type of the support.

We studied the catalytic properties of copper–cerium oxide systems, deposited on supports obtained by calcination of yttrium-stabilized zirconium dioxide at 300-1000 °C, in the reaction of selective oxidation of CO in a stream of hydrogen. We have shown that the catalytic activity of the samples obtained correlates with the activity of the original supports in the reaction of CO oxidation: the highest CO conversion is observed on catalysts with the highest and the lowest specific surface area.

Gas phase carbonylation of methane is studied in the presence of molecular oxygen over pure carbon carriers and carbon supported rhodium chalcogen halides. Activated carbons and fullerene blacks have been used as carbon supports. XPS and IR-spectroscopy data show the formation of rhodium chalcogen halides in solids prepared by different methods. We have found that the productivity of acetic acid by carbon supported rhodium chalcogen halides depends strongly on the carbon carrier and the method of the catalyst preparation. Namely, the catalyst with highest productivity for the acetic acid is prepared by synthesizing the rhodium chalcogen halide over the carbon support followed by thermal destruction. We have also found that rhodium chalcogen halides over activated carbons are more active compared with fullerene supported catalysts.

The morphological and catalytic properties of samples of nanomeric zirconium dioxide, stabilized with yttrium oxide, manufactured via the effect of a UHF field during the process of drying precipitated zirconium hydroxide and calcination at temperatures from 300 to 1000 °C, were studied. It was shown that the highest activity in the oxidation of CO occurred with 40 nm particles of zirconium dioxide prepared at 1000 °C.

New rhodium selenochlorides Rh4Se16Cl10 and Rh4Se18Cl10 whose structure is based on the cluster “cubane” [Rh4(μ3-Se)4] and products of their thermal transformations were obtained. The catalytic properties of the compounds on various carbon and silica supports in oxidative carbonylation of methane in the gas phase and their dependence on the catalyst preparation technique, type of support, and size of its nanopores were analyzed.

The catalytic characteristics of systems prepared by mechanically mixing iron oxide nanoparticles, produced in the thermolysis of carboxylate complexes at 300–750°C, with aluminum oxide in the oxidation of CO were studied. It was shown that increase in the size of the iron oxide nanoparticles leads to decrease in the catalytic activity of the samples as a result of their different structural and textural characteristics, which change in relation to the synthesis conditions.

A study was carried out on the oxidation of CO on catalysts with different fractal dimension in kinetic and internal diffusion modes. A linear relationship was found between the fractal dimension of the catalyst DF and the γ coefficient in the reaction-diffusion equation. The fractal dimension of the catalyst could be calculated from the macrokinetic measurements.

We have studied the catalytic properties of copper-cerium oxide catalysts, supported on zirconium, aluminum, titanium, and manganese oxides, in the reaction of selective oxidation of CO in hydrogen-rich mixtures. We have shown that the high activity and selectivity of catalysts supported on zirconium and aluminum oxides is connected with the presence of (in addition to divalent copper) higher amounts of copper in the (+1) oxidation state in the catalysts.

We propose a simple method for the qualitative study of charge processes in a liquid crystal layer at the silicon surface. The method is based on the field effect that has been induced by charges that are localized near the silicon surface. The method is sensitive to the sign of accumulating charge and does allow monitoring a change of the surface charge.

Addition of a small amount of oxygen to synthesis gas promotes the formation of oxygen-containing compounds (methanol, dimethyl ether) during the hydrogenation of CO over palladium supported on zirconium, aluminum, magnesium, lanthanum, and silicon oxides. The maximum effect on the rate of formation of oxygen-containing compounds was observed with 0.5–2.0 vol.% of oxygen in synthesis gas.

The electrochemical reduction of 1,1-dihalo-2-R-2-methylcyclopropanes was studied by polarography and preparative electrolysis. A mixture of stereoisomeric monoboro- and monochlorocyclopropanes was obtained with preparative yield of 60–70% in preparative electroreduction in methanol against a background of 0.1 M LiClO4. In the case of bromine derivatives of cyclopropanes (except when R = CN) an effect was found on the part of the current density on the ratio of cis and trans isomers, which was interpreted as a change, in dependence on current density, of the contributions of the reactions of reduction of the starting compounds (SN2 mechanism) and ionic pairs (SN1 mechanism). The effect of the solvent (CHCl3, DMF, DMSO, MeOH) and background salt (LiClO4, Et4NBr) on the ratio of stereoisomers is in agreement with this interpretation.

By analyzing the kinetics of heterogeneous (electrode) and homogeneous reduction for benzyl phenyl ether it was found that toluene and phenol are formed via the transfer of two electrons and the breaking of the PhO-Bz bond. It was shown that electron transfer constitutes the slow stage in heterogeneous and homogeneous reduction. The homogeneous transfer coefficient was approximately 0.5, which represents a significant difference from the heterogeneous value.

A study has been made of the influence of Co(II) and Ni(II) ions on the kinetics of the homogeneous reduction of gem-dichlorocyclopropanes by anthracene anion radicals. It has been shown that Co(II) and Ni(II) ions accelerate this process. The observed effect depends on the nature and concentration of the metal ion and also on the type of gem-dichlorocyclopropane. Two mechanisms are examined: 1) homogeneous reduction of metal ions by anthracene anion radicals with the formation of univalent and zero-valent metals that are more effective reducting agents; and 2) activation of a dichlorocyclopropane molecule by previous coordination with a metal ion.

The flow of a gaseous mixture of hydrocarbons and carbon dioxide through a model reservoir with a stationary hydrocarbon liquid phase has been investigated theoretically and experimentally. The possibility of the onset of liquid-phase flow as a result of the accumulation of gaseous products is demonstrated.

This work concerns the experimental study of potential possibility to use the ITO/5CB/Si/Al structures based on a low resistive silicon as liquid crystal spatial light modulator (LC SLM). It is shown, that in such type of structures there are at least two charge processes causes the opposite influence on electrooptic reaction of structure. First process is connected with ion charge accumulation at silicon surface that induces the formation of depleted surface layer in silicon by means of a field effect. Second one is due to leakage current through Si/liquid crystal interface that decreases a photosensitivity of structure. Because of sufficient large ion currents achieved in such a type of structure as well as charge accumulation the possibility exists to form the local variable area of high ion concentration in liquid crystal layer that can play a role of a “quasi”-electrode which enables to modulate a surface conductivity of silicon. Ion control of photosensitivity as well as dynamic selection of input image by the structure has been demonstrated.

The current state, structure of total hydrocarbon resources (THCRs), their spatial distribution, and interrelation determine, as is known, the strategy and tactics of further exploration. Practical experience in evaluating THCRs showed that the most reliable results are obtained most often for zones of oil and gas accumulation (ZOGA) or their parts. The following main ZOGA have been isolated on the Barents Sea shelf: (a) in the northern sea part of the Timan; (b) in the South Barents gas and oil region; (c) in the North Barents potential oil and gas region and adjacent regions. The following main ZOGA can be distinguished on the shelf of the Laptev Sea: Minin arch, Trofimov zone of uplifts, Middle Laptev saddle, and the sea parts of the Lobaz-Nordvik and Tuvan`-Anabar arches in the Khatanga Gulf. Seismic exploration to prepare local structures for deep drilling and drilling of individual parametric and exploratory wells is most expedient in the following ZOGA: Luna, Nadezhda, Gusinozemel`sk, and Admiralteistvo in the Barents Sea; Obruchev and Skuratov in the Kara Sea; Minin and Trofimov in the Laptev Sea. When planning offshore exploration and the presence of ZOGA with a high concentration of THCRs is a necessary but not a sufficientmore » condition, since the existing arsenal of technical means is limited. This especially concerns the development of offshore fields, particularly in waters with severe ice conditions. Therefore, it is necessary to take into account the technical accessibility of various ZOGA for the complete cycle of works on developing offshore fields.« less

The promotion of hydrogenation of CO to methanol and dimethyl ether by oxygen over supported palladium catalysts increases with increasing oxygen content in the reaction mixture, but the system, becomes less stable with time. A high level of selectivity with respect to oxygen-containing compounds may be achieved by periodic introduction of oxygen into the synthesis gas.

It has been established that several aromatic hydrocarbons are formed in CO hydrogenation over silica gel-supported palladium catalysts. A mechanism for the formation of reaction products is suggested.

Injection currents in diphenylbutadiene (DPB), diphenylhexatriene (DPHT), and diphenyloctatetraene (DPOT) films obtained by thermal vacuum deposition have been studied. From temperature measurements of the space-charge-limited currents (SCLC) the trap parameters are determined and the current carrier mobility are calculated in films of the studied substances. The experimental results show that the change of the film structure causes trap energy distribution changes in the forbidden bands of these substances. These traps are supposed to be of a structural nature. Es wurden Injektionsstrome in Diphenyl-Butadien (DPB)-, Diphenyl-Hexatrien (PPHT)-und Diphenyl-Oktatetraen (DPOT)-Schichten, die im Vakuum thermisch aufgedampft wurden, untersucht. Aus den Temperaturmessungen der raumladungsbegrenzten Strome (SCLC) werden die Haftstellenparameter bestimmt und die Beweglichkeiten der Ladungstrager der untersuchten Substanzen berechnet. Die experimentellen Ergebnisse zeigen, das die Anderung der Schichtstruktur eine Anderung der Haftstellen-Energieverteilung in der verbotenen Zone dieser Substanzen verursacht. Es wird angenommen, das diese Haftstellen von struktureller Natur sind.

We studied the possibility of improving the service properties of porcelain using the method of prior treatment of the specimens in salt solutions after the first firing. We used a hard procelain body of the following composition (weight content, %): 30-40 Prosyanovski kaolin, 0-i0 Glukhovetsk kaolin, 21.5 Vodolazhsk quartz sand, 14 Chupinsk milled pegmatite (containing 21-25% quartz), i0 Belogorsk feldspar, 12 Veselovsk clay, 2.5 commercial purity (technological) alumina, 1.5 (above 100%) sulfite-alcoholic slop, and also, a glaze containing 41.5 Vodolazhsk quartz sand, 20.3 Chupinsk feldspar, 9.2 Kovrovsk dolomite, 6.5 Prosyanovsk kaolin (fired) 5.8 Prosyanovsk kaolin (raw), 8.3 Chupinsk finely milled pegmatite (containing 21-25% quartz), 5.6 marble, 0.5 zinc oxide, 2.2 commercial purity alumina, and 1 (above 100%) Ogianlinsk bentonite.

This work shows the results of an NMR investigation of reactions of 3,3-dimethylcyclopropene, 3-methyl-3-phenylcyclopropene, and 3-methyl-3-cyanocyclopropene with methylsulfenyl chloride, ethylsulfenyl chloride, and phenylsulfenyl chloride. It has been found that sulfenyl halides easily form adducts with cyclopropenes even at -20 to -50/sup 0/C.ctivity