On the topological representation of catalytic cycles with nonlinear steps

Reaction route analysis is applied to visualize reaction networks in several heterogeneous catalytic reactions. Combination of the theory of complex reactions with the notion of catalytic cycles results in a topological representation of complex mechanisms with the nodes comprising all possible surface species including free sites and branches indicating interconnections between reactions.     

On the validity of Langmuir adsorption on supported nanoparticles

The general form for adsorption on nanoparticles is presented. Conditions for the validity of Langmuir adsorption isotherm for supported nanoparticles are discussed.     

On linear free energy correlations in liquid-phase catalytic hydrogenation of aromatic compounds

Application of linear free energy relationships (correlation between kinetics and thermodynamics) to catalytic hydrogenation of aromatic compounds in the liquidphase over supported metal catalysts is discussed.     

Quantum effects in submillimetre hot hole semiconductor lasers

The hole dynamics and emission processes in degenerate band semiconductors in strong crossedE B fields were studied both theoretically and experimentally. The Luttinger effective mass Hamiltonian was used to study the Landau level energy spectrum in anisotropic valence bands of Ge. The dependence of the energy spectrum onE,H fields orientation is analysed. The role of quantum effects, such as interaction and mixing of light and heavy hole states in the scattering process and Landau level population is studied. The results of experimental studies of stimulated emission spectra for intersub-band and cyclotron transitions as well as their dependence onE,H field orientation are presented, the experimental data being in good agreement with the quantum model calculations.     

Biochemical and Structural Studies of Conserved Maf Proteins Revealed Nucleotide Pyrophosphatases with a Preference for Modified Nucleotides

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Conversion of ethanol into hydrocarbon components of fuels in the presence of Pd-Zn-containing catalysts

The features of ethanol conversion into hydrocarbons C₄-C₁₂ in the presence of the novel catalyst Pd-Zn/γ-alumina and pilot zeolite system Pd-Zn/MFI/γ-alumina were studied (MFI is high-siliceous zeolite with ZSM-5 type structure). The structure of active sites changes noticeably in the course of preliminary activation and catalytic reaction. High selectivity and stability of the zeolite-containing Pd-Zn catalyst in alcohol conversion into hydrocarbon components of fuels is related to the stable composition of the alloy that forms clusters PdZn. At the same time, the alumina-based catalyst loses stability due to zinc diffusion from the alloy into γ-Al₂O₃ to form the spinel structure.     

Overview of catalytic methods for production of next generation biodiesel from natural oils and fats

Production of biodiesel from natural oils and fats can be achieved using various technologies briefly discussed in this review. A particular appealing concept for production of green diesel is selective catalytic deoxygenation of renewables leading to diesel fuel products. This reaction can be performed over Pd on active carbon supports with saturated and unsaturated fatty acids and their derivatives.