34 research outputs found
Hydrogen Activation by Benzene-Ruthenium Complexes in Aqueous Solution: Synthesis, Molecular Structure, and Intercalation of the Cluster Cation [{C₆H₆)₄Ru₄H₄]²⁺
The hydrogenation of the aqua complex [(C6H6)Ru(H2O)3]2+, prepared in situ by hydrolysis of (C6H6)2Ru2Cl4 in water, was found to lead to the tetranuclear cluster dication [(C6H6)4Ru4H4]2+ (1) which crystallizes as the dichloride from the aqueous solution. In the presence of acetate ions, however, the reaction yields the dinuclear cations [(C6H6)2Ru2H(OOCCH3)X]+ (X=OH: 2, X=Cl: 3) which crystallize as the hexafluorophosphate salts. The X-ray crystal-structure analysis of [(C6H6)4Ru4H4]Cl2 reveals the cluster dication 1 to consist of a tetrahedral ruthenium framework; the four hydrido ligands are presumably coordinated to three faces and to one edge of the Ru4 tetrahedron. The cationic complexes 1 and 2 have been found to intercalate in sodium hectorite
Ruthenium Nanoparticles Intercalated in Hectorite: A Reusable Hydrogenation Catalyst for Benzene and Toluene
The cationic organometallic aqua complexes formed by hydrolysis of [(C6H6)RuCl2]2 in water, mainly [(C6H6)Ru(H2O)3]2+, intercalate into sodium hectorite by ion exchange, replacing the sodium cations between the anionic silicate layers. The yellow hectorite thus obtained reacts in ethanol with molecular hydrogen (50 bar, 100°C) with decomposition of the organometallic aqua complexes to give a black material, in which ruthenium(0) nanoparticles (9-18nm) are intercalated between the anionic silicate layers, the charges of which being balanced by hydronium cations. The black ruthenium-modified hectorite efficiently catalyses the hydrogenation of benzene and toluene in ethanol (50 bar H2, 50°C), the turnover frequencies attaining 7000 catalytic cycles per hou
Повышение маневренности парогазовой установки в условиях реального энергетического рынка
В данной работе рассматривается анализ маневренности парогазовой установки в условиях реального энергетического рынка. Произведен расчет тепловой схемы парогазовой установки ПГУ-420. Произведена оценка влияния начального давления контуров ВД и НД на электрическую мощность. Оценено влияние конечного давления, температуры наружного воздуха, температуры газов на входе в газовую турбину на электрическую мощность ПГУ.In this paper, we analyze the maneuverability of a combined cycle plant in a real energy market. The calculation of the thermal circuit of the combined cycle plant PGU-420. The influence of the initial pressure of the VD and ND circuits on the electric power is estimated. The influence of the final pressure, the temperature of the outside air, the temperature of the gases at the inlet of the gas turbine on the electric capacity of the CCGT unit is estimated
Finite volume approach for the instationary Cosserat rod model describing the spinning of viscous jets
The spinning of slender viscous jets can be described asymptotically by
one-dimensional models that consist of systems of partial and ordinary
differential equations. Whereas the well-established string models possess only
solutions for certain choices of parameters and set-ups, the more sophisticated
rod model that can be considered as -regularized string is generally
applicable. But containing the slenderness ratio explicitely in the
equations complicates the numerical treatment. In this paper we present the
first instationary simulations of a rod in a rotational spinning process for
arbitrary parameter ranges with free and fixed jet end, for which the hitherto
investigations longed. So we close an existing gap in literature. The numerics
is based on a finite volume approach with mixed central, up- and down-winded
differences, the time integration is performed by stiff accurate Radau methods
Ruthenium Nanoparticles Intercalated in Hectorite: A Reusable Hydrogenation Catalyst for Benzene and Toluene
The cationic organometallic aqua complexes formed by hydrolysis of [(C6H6)RuCl2]2 in water, mainly [(C6H6)Ru(H2O)3]2+, intercalate into sodium hectorite by ion exchange, replacing the sodium cations between the anionic silicate layers. The yellow hectorite thus obtained reacts in ethanol with molecular hydrogen (50 bar, 100°C) with decomposition of the organometallic aqua complexes to give a black material, in which ruthenium(0) nanoparticles (9–18 nm) are intercalated between the anionic silicate layers, the charges of which being balanced by hydronium cations. The black ruthenium-modified hectorite efficiently catalyses the hydrogenation of benzene and toluene in ethanol (50 bar H2, 50°C), the turnover frequencies attaining 7000 catalytic cycles per hour