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1.
Selectivity of erionite and mordenite type aluminosilicates synthesized in the presence of B3+, Ga3+ or Fe3+ has been studied in methanol conversion to hydrocarbons. The olefin to paraffin ratio in the product is proportional to the Al2O3 content of the zeolites.
, B3+, Ga3+ Fe3+. , / Al2O3 .
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2.
Resin supported palladium metal was prepared from [Pd(NH3)4]-form sulfonic resin by treatment: with H2. The CO adsorption and H2-D2 equilibration reaction were greatly promoted by treatment above 373 K where Pd(II) was reduced to Pd(O) as indicated by XPS study. The reaction rate is of the 2.5th order with respect to the metal sites.
, , [Pd(NH3)4]- H2. CO H2-D2 373 , Pd(II) Pd(0), . 2, 5 .
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3.
Liquid-phase catalytic hydrogenatio of E-cinnamaldehyde was carried out by using new supported nickel catalysts (Ni/AlPO4, Ni/AlPO4–Al2O3 and Ni/AlPO4–SiO2) in methanol as solvent under low hydrogen pressure (4.1 bar) and 298 K. The kinetic orders are zero in H2 and aldehyde. The selectivity to the hydrogenaton of the C=C double bond is very high (>99%)
- (Ni/AlPO4, Ni/AlPO4–Al2O3 Ni/AlPO4–SiO2) (4,1 ) 298 . H2 . C–C (>90%).
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4.
The preparation of vanadium catalysts is described using fluorine modified Aerosil as support. It is shown that modification with fluorine changes the concentration and topology of the surface silanol groups and, as a consequence, the catalytic properties.
, , . , , , .
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5.
Kinetic studies of hydrogen and carbon monoxide adsorption on reduced Re2O7/Al2O3 catalysts have revealed that its activation energy decreases with increasing reduction degree of rhenium oxide. Adsorption of gases is suggested to take place on metallic rhenium atoms.
- . , . , .
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6.
Molecular nitrogen and irradiation temperature are shown to affect the radiationchemical yield of O st in the radiolysis of N2O adsorbed on alumina with large surface areas and to exert no influence in the case of small surface areas of Al2O3.
, - O st N2O, Al2O3 .
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7.
The transformation of a dispersed high-temperature superconductor from its normal to superconducting state was found to result in the loss of its catalytic properties in orhto-para-hydrogen conversion.
, -- .
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8.
The rates of14N2 desorption from the surfaces of nitrides have been measured in the presence and absence of15N2 in the gas phase. Whatever the adsorption heat and the form of surface species, the adsorption of15N2 molecules does not affect the rate of14N2 desorption.
14N2 15N2 . , 15N2 14N2.
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9.
The MgO–VCl4 system was investigated by the ESR method. Reduction of VCl4 by the MgO surface to V3+ and V2+ (partly) is postulated.
MgO–VCl4 , VCl4 V+3 V+2, MgO.
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10.
The conditions for the formation of O 2 on VCl4/SiO2 catalysts have been investigated. It is shown that thermal vacuum treatment (TVT) of unhydrolyzed catalysts leads to partial hydrolysis of the surface vanadium complex caused by the silanol groups of the support. The ability of the catalysts to generate O 2 radicals was found to depend on the degree of hydrolysis caused by thermal vacuum treatment.
O 2 VCl4/SiO2. , , . , O 2 , .
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11.
New highly active catalysts for metathesis of olefins were obtained through the interaction of bis(acetylacetonato)dioxymolybdenum(VI) with surface OH groups of -Al2O3 and subsequent reduction in H2 or CO.
()(VI) OH -Al2O3 H2 CO .
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12.
Abstract A series of rare earth transition metal perovskites has been synthesized and the catalytic activity tested for 2-propanol decomposition. The effect of rare earth ions on the catalytic activity can been understood from the correlations obtained between the physico-chemical properties and the catalytic activity of the perovskites.
, , 2-. , - .
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13.
The function of SO2 in CO oxidation on Pd-V catalysts is to transform a rapid heterogeneous-homogeneous process to a slower heterogeneous one. High concentrations of CO also exert the same effect. In the heterogeneous process an increase in the SO2 concentration increasing the degree of catalyst reduction with and without Pd additives, promotes CO oxidation.
CO - SO2 - . CO. SO2, , , CO.
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14.
The effect of different alkali metal hydroxides on the metallic dispersity and catalytic activity of SiO2–AlPO4 (8020, by mass) supported palladium catalysts has been studied. The reduction by hydrogen transfer of benzylideneacetone and styrene (using cyclohexene and n-octanol, respectively, as hydrogen donors) and the liquid phase reduction of cyclohexene at low pressure (5 bar) in a Parr type reactor have been used as test reactions to follow changes in the catalytic activity.
(SiO2–AlPO4/8020 ). ( n-, , , (5 ) .
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15.
The non-catalyzed oscillation reaction of the aniline-KBrO3–H2SO4 system has been followed potentiometrically. The concentration regions of the beginning of oscillation are given in a triangular diagram. Also studied was the dependence of the induction period on concentration of the participants, which was described by a kinetic equation. The oscillation region extends to lower KBrO3 concentrations, the number of the oscillation jumps increases, and the induction period is shortened with increasing acidity.
-KBrO3–H2SO4. . . KBrO3, .
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16.
The interaction of diallylnickel with WS2 produces catalysts whose activity is 10–50 times higher than that of the parent sulfide. The atomic catalytic activity referred to supported nickel is independent of the catalyst type and the sulfur removed in temperature programmed reduction.
, WS2 , 10–50 . , , .
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17.
The kinetics of Fe3+ and Cu2+ sorption from sulfate salt solutions by fibrous polyampholite have been studied.
Fe3+ Cu2+ , .
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18.
Photoadsorption activity of SnO2 with respect to O2 and NO after CO chemisorption has been revealed to be drastically increased. Photoadsorption is suggested to be sensitized by surface carbonates formed due to CO chemisorption.
. , .
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19.
Specificity of the bands at 1630–1620 cm–1 in IR spectra of coordinatively bonded pyridine has been studied. Three strong Lewis-type acid centers have been revealed on Al2O3 surface.
- 1630–1620 –1.
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20.
Upon the decomposition of silica-supported ammonium paramolybdate, hexagonal MoO3 is formed at 300–350 °C. Irreversible transformation of hexagonal to rhombic MoO3 is observed with increasing calcination temperature. The hexagonal MoO3 structure is probably stabilized by the insertion of ammonium and silicon ions into the lattice of molybdenum trioxide.
, , 300–359 °C . MoO3 . MoO3, , MoO3.
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