The scientific cooperation of the Boreskov Institute of Catalysis with the catalytic communities from various countries is effected in accordance with various forms of cooperation: conducting joint seminars on catalysis, exchanging the information and appropriate materials, exchanging research fellows, visiting scientific centers, and participating in congresses and symposia on theoretical and applied catalysis.

According to research programs, projects and grants, the fundamentals of catalysis are studied jointly with researchers from various universities, institutions, research laboratories and companies. BIC collaborates fruitfully on a commercial basis with the leading companies from more than 20 countries, sells licenses, know-how and performs research projects according to client requests.

Academician Valentin N. Parmon is the Russian representative in the European Federation of Catalytic Societies (EFCATS), Member of the International Association of the Catalysis Societies (IACS).

FRANCE

According to the agreement between RAS and CNRS BIC collaborates with the Institute de Recherches sur la Catalyse et l’Environnement de Lyon (Research Institute on Catalysis and Environment), Villeurbanne, in the frame of the Russian-French European associated Laboratory on Catalysis headed by Prof. V. Parmon and Dr. M. Lacroix. The Laboratory was established by an agreement signed December 6, 2004 in Moscow by RAS and CNRS. Four areas of research were identified:

• Catalysis and Energy: Production of Syngas and Hydrogen
• Catalysis and Environment: Treatment of Waste Waters
• Catalysis and Fine Chemistry: Pollution-Free Catalytic Processes
• Advanced Spectroscopic Methods: Mobility of Species in Porous Medium.

INDIA

In the frame of RAS-DST Long Term Programme of cooperation in science and technology BIC collaborates with National Chemical Laboratory, Pune. Coordinators on the Program “Catalysis” are Prof. V. Parmon and Prof. S. Sivaram.

GERMANY

The cooperation in the frame of the agreement between RAS and German Scientific Research Society (GSRS) with Fritz-Haber-Institut der Max-Planck-Gesellschaft, Berlin, on the Project “Development of in situ Methods for Study of Solid Surfaces”. Coordinators: Prof. V. Bukhtiyarov (BIC) and Prof. R. Sсhlögl (Fritz-Haber-Institut der MPG)

CHINA

The cooperation in the frame of Associated Research Laboratory which was established by an agreement signed December 4, 2004 by the Boreskov Institute of Catalysis and Heilongjiang University, Harbin. Chief Executive officers of Laboratory are: Prof. V. Bukhtiyarov, Prof. G. Echevsky (BIC) and Prof. Wu Wei (Heilongjiang University) on the Project “Synthesis and Modification of ZSM-12 Zeolites. Zeolite ZSM-12 in Reaction of Naphthalene Alkylation with Methanol”.

USA

The cooperation in the frame of the bilateral agreement with the Purdue University, Indiana.

EUROPEAN COMMUNITY SIXTH FRAMEWORK PROGRAM

I. Co-Processing of Upgraded Bio-Liquids in Standard Refinery Units

Coordinator: Dr. Y. Solantausta, VTT Processes, Espoo, Finland

Partners:
Rijksuniversiteit Groningen, The Netherlands; Boreskov Institute of Catalysis, Novosibirsk, Russia (Prof. V. Kirillov); Uhde Hochdrucktechnik GmbH, Germany; BTG Biomass Technology Group BV, The Netherlands; University of Twente, The Netherlands; STFI-PACKFORSK AG, Sweden; Institute of Wood Chemistry, Hamburg, Germany; Slovenian Institute of Chemistry, Slovenia; Arkema SA, France; Helsinki University of Technology, Finland; ALMA Consulting Group SAS, France; INEOS Phenol, Germany; Metabolic Explorer, France; Shell Global Solutions International, The Netherlands; Pacific Northwest National Laboratory (PNNL), USA; Johnson Matthey, UK.

EUROPEAN COMMUNITY SEVENTH FRAMEWORK PROGRAM

I. Reforming of Crude Glycerin in Supercritical Water to Produce Methanol for Re-Use in Biodiesel Plants

Coordinator: J. Vos, BTG BiomassTechnology Group BV, The Netherlands

Partners:
Acciona Servicios Urbanos, Spain; Boreskov Institute of Catalysis, Novosibirsk, Russia (Prof. V. Kirillov); Rijksuniversiteit Groningen, The Netherlands; University of Maribor, Slovenia; UHDE High Pressure Technologies GmbH, Germany; SPARQLE International BV, The Netherlands.

II. Engine and Turbine Combustion of Bioliquids for Combined Heat and Power Production

Coordinator: J. Vos, BTG BiomassTechnology Group BV, The Netherlands

Partners:
AMO ZIL, Moscow, Russia; Aston University, Birmingham, UK; Boreskov Institute of Catalysis, Novosibirsk, Russia (Prof. V. Kirillov); BTG Biomass Technology Group BV, The Netherlands; Central Scientific Automobile and Automotive Engines Institute, NAMI, Moscow, Russia; Encotech BV, The Netherlands; University of Florence, Florence, Italy.

III. Oxidative Coupling of Methane Followed by Oligomerization to Liquids

Coordinator: G. Marin, Ghent University, Belgium

Partners:
Bayer Technology Service, Germany; Institute de Recherches sur la Catalyse et l’Environnement de Lyon, Villeurbanne, France; Ruhr-Universität Bochum, TECHEM, Bochum, Germany; Instituto de Technologia Quimica, Spain; Johnson Matthey, UK; SINTEF, Trondheim, Norway; Linde Engineering, Germany; Cepsa R&D Center, Spain; Haldor Topsoe, Denmark; Universitetet i Oslo, Oslo, Norway; University of Cambridge, UK; ALMA Consulting Group, France; Boreskov Institute of Catalysis, Novosibirsk, Russia (V. Sadykov); INEOS, Belgium; Institut fur Mikrotechnik Mainz Gmbh, Germany; Eni SpA, Italy.

IV. Design and Manufacturing of Catalytic Membrane Reactors by Developing New NanoArchitectured Catalytic and selective Membrane Materials (DEMCAMER)

Coordinators: Fernando Espiga Guy Marin and/or Inaki San Sebastian, Fundacion Tecnalia Research & Innovation, Spain

Partners:
Vlaamse Instelling voor Technologisch Onderzoek N.V., Belgium; Universita della Calabria, Italy; Technische Untversiteit Eindhoven, Netherlands; Agencia Estatal Consejo Superior de Investigaciones Cientificas, Spain; Fraunhofer-Gesellschaft zur Foerderung der Angewandten Forschung e.V., Germany; Boreskov Institute of Catalysis, Russia (Dr. I.Z. Ismagilov); Institut National de l'Environnement et des Risques Ineris, France; Rauschert Kloster Veilsdorf GMBH, Germany; Ceramic Powder Technology AS, Norway; Hybrid Catalysis BV, The Netherlands; HyGear B.V., The Netherlands; Abengoa Bioenergia Nuevas Tecnologias SA, Spain; Guascor Ingenieria S.A., Spain represented; Quantis Sari, Switzerland; Höganäs AB, Sweden; Total Petrochemicals Research Feluy, Belgium; Total Petrochemicals France SA, France.

The advertising and information activities are universal marketing tools for establishing professional contacts. Again, this is a necessary part of the market examination to be settled in the world. Each year, achievements of the Boreskov Institute of Catalysis are demonstrated at the very prestigious exhibitions in Russia and abroad. The goal is to strengthen collaboration with the present partners and to attract attention of potential customers.

In 2011, the most important BIC’s achievements in the area of applied catalysis were presented at the Exhibitions:

• ™ Exhibition “Scientific and Technological and Innovation Achievements of Russia” arranged in the frames of Year of Russia in Spain, May 12-15, Madrid, Spain.

Diploma

• ™ Exhibition “Present Day Ceramic Materials. Properties. Technologies. Application”, August 14-16, Novosibirsk, Russia.
• ™ XVII International Exhibition-Congress “High Technologies. Innovations. Investments” HI-TECH 2011), June13-19, St. Petersburg, Russia.
  Medal and Diploma of the 1 ^st degree for “Catalytic Heat Supply Installations”
  Medal and Diploma of the 1 ^st degree for “Catalytic Hot Air Generators”
• “SibPolyTech-2011”, October 18-21, Novosibirsk, Russia.
  Big Golden Medal and Diploma for “Technology for Production of Membrane Systems of the “Nafion” Type for Fuel Cells”
• ™ XVI International Exhibition of Chemical Industry and Science “Chemistry-2011”, October 24-27, Moscow, Russia.
  Medal and Diploma of the 1 ^st degree for “Technology for Production of Perfluorochemical Membrane Copolymers of “Nafion” Type for Fuel Cells”
• ™ “RusnanotechExpo-2011” in the frames of IV Nanotechnology International Forum, October 26-28, Moscow, Russia.
• ™ Russia-Vietnam Exhibition-Seminar “Energy Saving Technologies for Oil Chenistry and Ecology”, November 2-4, Hanoi, Vietnam.
• ™ The Specialized Inter-Regional Exhibition “YAKUTIA: Oil. Gas. Ecology. Energo-2011”, November 9-11, Yakutsk, Russia.

Solution of many specific problems requires joint efforts in order to promote its fastest accomplishing. International congresses, symposia, conferences, and seminars are the most productive to familiarize scientists with innovations outside their own research and to disseminate the information about the results achieved to a wider audience. One of the directions of the scientific-organizational work carried out in the Institute is aimed on conducting conferences and seminars with the participation not only of Russian scientists and researchers from fSU, but foreign participants as well.

• Монографии
• Книги
• Обзорные статьи
• Журнальные публикации
• Участие в конференциях, симпозиумах

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MODELING OF THE MECHANISM OF ONE-ELECTRON TRANSFER FROM THE PERYLENE MOLECULE TO THE OXYGEN MOLECULE ³O₂ IN THE HF MEDIUM

I.V. Kuz’min*, V.N. Solkan*, G.M. Zhidomirov, V.B. Kazanskii* (*Zelinsky Institute of Organic Chemistry, Moscow, Russia)

Kinet. Catal., 52(2) (2011) pp. 192-196.

The thermodynamic parameters of the formation of the perylene radical cation in anhydrous hydrogen fluoride containing dissolved dioxygen were calculated by the ab initio method MP2. The protonated product of HF autoprotolysis was modeled as the H(FH)₃⁺ cluster. The ³O₂ molecule was found to bind to the linear H(FH)₃⁺ cluster via a hydrogen bond. As the charge and multiplicity of the system change upon the capture of an electron, the oxygen-hydrogen fluoride cluster complex undergoes rearrangement to yield the hydroperoxyl radical OOH incorporated in a cycle formed by HF molecules. The free energy of electron transfer from the perylene molecule to the ³O₂ molecule in the HF medium is about -38 kcal/mol.

(*Anti-Infective Drug Research Center, Almaty, Kazakhstan)

Nat. Sci., 3(7) (2011) pp. 573-579.

The interaction of molecular iodine with virus DNA nucleotide is studied by ab initio RHF/3-21G** method. Formation of the nucleoprotein complex of the HIV DNA, molecular iodine and the HIV-1 integrase co-factor is considered to cause the inhibition action of the integrase enzyme. Experimental data on the anti-HIV effect of the molecular iodine complex compounds and the results of calculations suggest that molecular iodine contained in iodine polymer complexes may be considered as a compound inhibiting the catalytic center of the integrase enzyme. Unlike the known integrase inhibitors, molecular iodine also changes the virus DNA structure and produces the N-I bond in the purine bases of adenosine and guanosine nucleotides.

(*Moscow Lomonosov State University, Moscow, Russia; **University of Stockholm, Stockholm, Sweden; ***University of Namur, Namur, Belgium)

J. Catal., 281(2) (2011) pp. 212-221.

It is shown that carbonates can be formed with almost no energetic barrier from CO₂ and metal-oxide binuclear MO_xM species (M = Mg, Ca, Sr, Ba, with X = 1–4, depending on the cation) in alkaline earth zeolites, mordenite (MOR) and phillipsite (PHI), on the basis of quantum mechanical density functional theory (DFT) calculations at both isolated cluster and 3D periodic levels. The participation of MO_xM species (X = 1 and 3) explains the source of the third O atom in CO₃ species in dehydrated zeolites, on the basis of a good agreement between the calculated and experimental positions of the asymmetric and symmetric CO₃ vibration bands, of the ratio of their intensities, and of the weak dependence versus the cation and framework type. The reaction of formation of dimethylcarbonate from CaCO₃Ca in the 8-membered (8R) ring of MOR and methanol has also been considered, suggesting the carbonate activity as the source of CO₂ at elevated temperatures.

A.A. Rybakov*, A.V. Larin*, G.M. Zhidomirov, D.N. Trubnikov*, D.P. Vercauteren** (*Moscow Lomonosov State University, Moscow, Russia; **University of Namur, Namur, Belgium)

Comput. Theor. Chem., 964(1-3) (2011) pp. 108-115.

A new CO oxidation mechanism occurring at (MgO₂Mg)²⁺ oxide clusters in different zeolites is modeled at both the periodic DFT (PDFT) level for Mg-phillipsite and with the cluster approach for zeolite Y and mordenite. Using PDFT, the authors obtained a value of reaction activation energy (15.3 kcal/mol) that is lower than the one obtained using the isolated cluster approach (35 kcal/mol).

The main reason of the lower barrier is the strong CO chemisorption, which was not obtained with the cluster approach. The lower oxidation activity of the Mg zeolite forms is due to the smaller number of active singlet MgO_xMg species compared to those in the other alkaline earth zeolites.

E.N. Golubeva*, O.I. Gromov*, G.M. Zhidomirov(*Moscow Lomonosov State University, Moscow, Russia)

J. Phys. Chem. A, 115(28) (2011) pp. 8147-8154.

DFT calculations were used for studying the structure and reactivity of organocuprates(II) usually considered as intermediates with very weak Cu-C bond. It was found that calculated principal g-tensor values of model compounds RCu(II)Cl^2- are similar to the experimentally found values for organocopper product of photolysis of quaternary ammonium tetrachlorocuprates. The calculations confirm that the most of organocuprates(II) could be stable at ambient conditions, and short lifetimes of organocuprates(II) in solutions or soft matrices are caused by their high reactivity in various bimolecular processes; the rate of those may be close to the rate of diffusion controlled reactions. The charges, spin densities, and d-orbital populations of the Cu atom in them are typical for bivalent copper complexes. Natural bond orbital analysis of organochlorocuprates(II) confirms the formation of polar σ-bond between copper and carbon atoms.

D.E. Zavelev*, M.V. Tsodikov*,cvG.M. Zhidomirov, R.A. Kozlovskii* (*Topchiev Institute of Petrochemical Synthesis, Moscow, Russia)

Kinet. Catal., 52(5) (2011) pp. 659-671.

A quantum-chemical study of the mechanism of ethylene oxide hydration on titanium oxide (anatase) modified with phosphorus additives was performed. It was demonstrated that the hydroxyl groups of the anatase surface are of importance for the activation interaction of ethylene oxide with the catalyst surface. The activation of the ethylene oxide molecule and proton transfer occurs with the participation of these hydroxyl groups. It was found that the modification of the titanium oxide surface with phosphorus additives plays a crucial role in proton transfer.

H. Gronbeck*, V.P. Zhdanov (*Chalmers University of Technology, Göteborg, Sweden)

Phys. Rev. B: Condens. Matter, 84(5) (2011) 052301 (4 pp.)

The density functional theory (DFT) is used to study the effect of lattice strain on hydrogen diffusion in Pd. The activation energy for this process is found to increase dramatically with increasing compressive lattice strain. In particular, the activation energy is close to double for an isotropic compression of 5% both in the alpha and beta phases. For tensile strain, the activation energy is instead decreased. This finding has important consequences for the interpretation of various kinetic processes occurring with participation of hydrogen and other interstitial atoms in macroscopic solid samples and nanoparticles.

I.V. Yudanov, A. Genest*, N. Rösch* (*Technische Universität München, Garching, Germany)

J. Clust. Sci., 22(3) (2011) pp. 433-448.

An important task for theory is the multi-scale modeling of catalytic properties of nanocrystallites with sizes ranging from clusters of few metal atoms to particles consisting of 10³–10⁴ atoms. To explore catalytic properties of nanosized metal catalysts, the authors developed an approach based on three-dimensional symmetric model clusters of 1–2 nm (~100 metal atoms) with fcc structure, terminated by low-index surfaces. With this modeling technique one is able to describe at an accurate DFT level various catalytic and adsorption properties of metal nanoparticles in quantitative agreement with experimental studies of model catalysts deposited on thin oxide films. Metal nanocrystallites exhibit properties that can significantly vary with their size and shape.

J. Phys. Chem. C, 115(44) (2011) pp. 21755-21762.

Molecular and dissociative forms of formic acid adsorption on the V₂O₅/TiO₂ model surface, possible intermediates, and transition states along of the dehydrogenation (HCOOH → CO₂ + H₂) and dehydration (HCOOH → CO + H₂O) pathways have been studied by the periodic density functional theory. The CI-NEB analysis of the reaction pathways showed that two types of molecular adsorbed HCOOH species initiate two completely different reaction channels. The first more stable adsorbed form is transformed into the surface formates, which decompose according to the “formate mechanism” to yield products of dehydrogenation, whereas the second weakly adsorbed molecular form decomposes, releasing CO and forming surface hydroxyls. Recombination of two surface hydroxyl groups V–OH to form adsorbed H₂O, followed by water desorption, completes the catalytic dehydration cycle without participation of the formate species. Comparison of the reaction pathways demonstrates that both dehydrogenation and dehydration of formic acid may occur over VO_x/TiO₂ model catalysts with the preferable dehydration pathway.

S.E. Malykhin, M.Yu. Burylin*, S.Yu. Burylin*, I.L. Zilberberg (*Kuban State University, Krasnodar, Russia)

J. Struct. Chem., 52(6) (2011) pp. 1098-1101.

Density functional theory in the plane wave basis set is used to study As adsorption on the Pd(111) surface in order to determine the action of a palladium chemical modifier used in electrothermal atomic absorption spectrometry (ETAAS). The calculated heat of desorption of the arsenic atom is 435 kJ/mole, which corresponds to the activation energy of arsenic atomization of 439 kJ/mole (in the range of high temperatures T > 1828 K), obtained by ETAAS. Based on the calculated data, the action of the palladium modifier for the determination of As is assumed to be controlled by the process of chemisorption.

M.I. Mamatkulov, J.-S. Filhol* (*Université Montpellier, Montpellier Cedex, France )

Phys. Chem. Chem. Phys., 13(17) (2011) pp. 7675-7684.

The authors have studied electrochemical vibrational and energy properties of CO/Pt(111) in the framework of periodic density functional theory (DFT) calculations. The authors have used a modified version of the previously developed Filhol-Neurock method to correct the unphysical contributions arising from homogeneous background countercharge in the case of thick metallic slabs. The stability of different CO adsorption sites on Pt(111) (Top, Bridge, Hcp, Fcc) has been studied at constant electric field. The energies are dominated by the surface dipole interaction with the external electric field: a strong positive electric field favors the surfaces with the lower dipole moment (that correspond to the ones with the lower coordination). The Stark tuning slope of the CO stretching frequency for a Top site was calculated for different surface coverages in very good agreement with both experimental and other theoretical results. Finally, an analysis of the origin of Stark shifts showing that the total Stark effect can be split into two competing components have been performed. The first one corresponds to the direct effect of charging on the C-O chemical bond: it is referred as an electrochemical effect. The second is the consequence of the surface dipole interaction with the applied electric field that modifies the C-O distance, inducing a change of the C-O force constant because of C-O bond anharmonicity: it is referred as the electromechanical effect. In the CO/Pt(111) case, the dominant contribution is electromechanical. The electrochemical contribution is very small because the electronic system involved in the surface charging is mostly non-bonding as analyzed by looking at the surface Fukui function.

ARE THE COMPLEX DISTRIBUTED GENETIC NETWORKS INHERENTLY OSCILLATORY AND CHAOTIC?

V.P. Zhdanov

JETP Lett., 93(1) (2011) pp. 41-45.

Complex mRNA-protein networks with distributed regulation of gene transcription are often mimicked by random Boolean networks. According to this mapping, the gene-expression kinetics are expected to depend strongly on the network connectivity, m. Specifically, the kinetics are predicted to be oscillatory or chaotic for m > 2. The authors analyze this problem in more detail by using an accurate model explicitly describing the mRNA-protein interplay with randomly organized transcriptional regulation. Contrary to the expectations, mean-field calculations and Monte Carlo simulations performed for m = 1, 2 and 4 show that oscillations and chaos are lacking irrespective of m.

Phys. Rep.-Rev. Sec. Phys. Lett., 500(1) (2011) pp. 1-42.

n cells, genes are transcribed into mRNAs, and the latter are translated into proteins. Due to the feedbacks between these processes, the kinetics of gene expression may be complex even in the simplest genetic networks. The corresponding models have already been reviewed in the literature. A new avenue in this field is related to the recognition that the conventional scenario of gene expression is fully applicable only to prokaryotes whose genomes consist of tightly packed protein-coding sequences. In eukaryotic cells, in contrast, such sequences are relatively rare, and the rest of the genome includes numerous transcript units representing non-coding RNAs (ncRNAs). During the past decade, it has become clear that such RNAs play a crucial role in gene expression and accordingly influence a multitude of cellular processes both in the normal state and during diseases. The numerous biological functions of ncRNAs are based primarily on their abilities to silence genes via pairing with a target mRNA and subsequently preventing its translation or facilitating degradation of the mRNA-ncRNA complex. Many other abilities of ncRNAs have been discovered as well. The review is focused on the available kinetic models describing the mRNA, ncRNA and protein interplay. In particular, the authors systematically present the simplest models without kinetic feedbacks, models containing feedbacks and predicting bistability and oscillations in simple genetic networks, and models describing the effect of ncRNAs on complex genetic networks. Mathematically, the presentation is based primarily on temporal mean-field kinetic equations. The stochastic and spatio-temporal effects are also briefly discussed.

Physica A, 390(1) (2011) pp. 57-64.

Kinetics of gene expression may be bistable or oscillatory due to the feedbacks between the RNA and protein synthesis. In complex genetic networks, kinetic oscillations may influence bistability. Following this line, the authors have performed a mean-field analysis and Monte Carlo simulations of periodic perturbation of the bistable kinetics of expression of two genes with mutual suppression of the mRNA production due to negative regulation of the gene transcription by protein. The perturbation is realized via modulation of the rate of the mRNA formation. In the mean-field kinetics, the mRNA and protein concentrations repeat themselves during each period. In the stochastic kinetics, this is also the case, provided that the modulation amplitude is small. If the modulation is appreciable, the latter kinetics exhibit new features. Specifically, the model predicts stochastic intermittence of the states of the genes. If the modulation amplitude is close to maximum, the change of the gene states during subsequent perturbation periods occurs fully at random. Taking into account that the model the authors use is generic, the results obtained are expected to be of interest far beyond the biophysics and biochemistry of gene expression.

Biophys. Rev. Lett., 6(1-2) (2011) pp. 1-12.

The authors present a kinetic model describing the growth of eukaryotic cells or, more specifically, the dependence of the cell volume on time in terms of the global interplay of the mRNA and protein synthesis and degradation and lipid synthesis. Addressing two long-standing questions in this interdisciplinary field, the authors explain why the average protein concentration in growing cells is nearly constant and the growth can accurately be fitted by using a bilinear or exponential function.

Central Eur. J. Phys., 9(4) (2011) pp. 909-918.

In eukaryotic cells, the mRNA-protein interplay can be dramatically influenced by non-coding RNAs (ncRNAs). Although this new paradigm is now widely accepted, an understanding of the effect of ncRNAs on complex genetic networks is lacking. To clarify what may happen in this case, a mean-field kinetic model was proposed describing the influence of ncRNA on a complex genetic network with a distributed architecture including mutual protein-mediated regulation of many genes transcribed into mRNAs. ncRNA is considered to associate with mRNAs and inhibit their translation and/or facilitate degradation. Results are indicative of the richness of the kinetics under consideration. The main complex features are found to be bistability and oscillations. One could expect to find kinetic chaos as well. The latter feature has however not been observed in calculations. In addition, the authors illustrate the difference in the regulation of distributed networks by mRNA and ncRNA.

Chaos, 21(2) (2011) 023135 (7 pp.).

The experiments indicate that the transcription of genes into ncRNA can positively or negatively interfere with transcription into mRNA. Two kinetic models are proposed describing this effect. The first model is focused on the ncRNA-induced chromatin modification facilitating the transcription of the downstream gene into mRNA. The second model includes the competition between the transcription into ncRNA and the binding of activator to a regulatory site of the downstream gene transcribed into mRNA. The analysis based on the mean-field kinetic equations and Monte Carlo simulations shows the likely dependences of the transcription rate on RNA polymerase concentration in situations with different rate-limiting steps. The models can also be used to scrutinize the dependence of the transcription rate on other kinetic parameters. Kinetic Monte Carlo simulations show that the first model predicts stochastic bursts in the mRNA formation provided that the transcription into ncRNA is slow, while the second model predicts in addition anti-phase stochastic bursts in the mRNA and ncRNA formation provided that that the protein attachment to and detachment from a regulatory site is slow.

Central Eur. J. Phys., 9(5) (2011) pp. 1366-1371.

Recent experiments indicate that several viruses may encode microRNAs (miRNAs) in cells. Such RNAs may interfere with the host mRNAs and proteins. A kinetic analysis of this interplay s presented. The viral miRNA is considered to be able to associate with the host mRNA with subsequent degradation. This process may result in a decline of the mRNA population and also in a decline of the population of the protein encoded by this mRNA. With these ingredients, it was first shown the types of the corresponding steady-state kinetics in the cases of positive and negative regulation of the miRNA synthesis by the protein. In addition, the authors scrutinize the situation when the protein regulates the virion replication or, in other words, provides a feedback for the replication. For the negative feedback, the replication rate is found to increase with increasing the intracellular virion population. For the positive feedback, the replication rate first increases and then drops. These features may determine the stability of steady states.

V.P. Zhdanov, B. Kasemo* (*Chalmers University of Technology, Göteborg, Sweden)

Chem. Phys. Lett., 513(1-3) (2011) pp. 124-126.

Supported lipid bilayers are often studied by using quartz crystal microbalance with dissipation monitoring (QCM-D). The interpretation of the QCM-D data usually implies the no-slip boundary condition at the substrate (QCM) surface. Under certain circumstances, the oscillations of the QCM crystal may however result in the transition to slipping conditions. Employing the Frenkel-Kontorova model, the authors show that during this transition the amplitude of the bilayer vibrations drops in a stepwise fashion, i.e., the process can be classified as a first-order kinetic phase transition. The model allows also to scrutinize the corresponding changes in the force between the bilayer and support and dissipation of energy.

React. Kinet. Mech. Catal., 103(1) (2011) pp. 11-18.

Reduction of NO by NH₃ in the presence of O₂ may occur on single Fe or Cu atoms or dimers incorporated into the inner walls of a zeolite. Although this process is of considerable intrinsic interest as an example of complex reactions running on single sites and is also important from the perspective of environmental chemistry, its mechanism is still open for debate. One of the likely schemes of the process implies the formation of N₂ and H₂O via the reaction of gas-phase NO and adsorbed NH₃. The author presents a detailed analysis of the steady-state kinetics corresponding to this scheme. The model employed includes eleven elementary steps. The results obtained allow one to interpret the apparent reaction orders observed experimentally.

React. Kinet. Mech. Catal., 104(2) (2011) pp. 267-272.

Reduction of NO by NH₃ in the presence of O₂ may occur on single Fe or Cu atoms or dimers incorporated into the inner walls of zeolite. One of the likely schemes of this reaction implies the formation of N₂ and H₂O through the reaction of gas-phase NO and adsorbed NH₃. The steady-state kinetics corresponding to this scheme was recently analyzed by the author assuming that the reaction runs on single metal atoms. In this work, the author presents a model including two metal atoms. Under the practically important conditions, the kinetics predicted by the one- and two-site models are demonstrated to be similar. In particular, both models allow one to interpret the apparent reaction orders observed experimentally.

JETP Lett., 93(9) (2011) pp. 551-554.

Recent experiments indicate that many viruses can move between cells directly via the cell–cell contacts without diffusing through the extracellular environment. The first generic kinetic model is presented describing intracellular viral kinetics in combination with this mode of spread of virions. Monte Carlo simulations show the specifics of the propagation of the infection front in this case.

M. Bally*, A. Gunnarsson*, L. Svensson**, G. Larson***, V.P. Zhdanov, F. Hook* (*Chalmers University of Technology, Göteborg, Sweden; **University of Linköping, Linköping, Sweden; ***University of Gothenburg, Göteborg, Sweden)

Phys. Rev. Lett., 107(18) (2011) 188103 (5 pp.).

Glycosphingolipids are involved in the first steps of virus-cell interaction, where they mediate specific recognition of the host cell membrane. The authors have employed total-internal-reflection fluorescence microscopy to explore the interaction kinetics between individual unlabeled noroviruslike particles, which are attached to a glycosphingolipid-containing lipid bilayer, and fluorescent vesicles containing different types and concentrations of glycosphingolipids. Under association equilibrium, the vesicle-binding rate is found to be kinetically limited, yielding information on the corresponding activation energy. The dissociation kinetics are logarithmic over a wide range of time. The latter is explained by the vesicle-size-related distribution of the dissociation activation energy. The biological, pharmaceutical, and diagnostic relevance of the study is briefly discussed.

V.P. Zhdanov, B. Kasemo* (*Chalmers University of Technology, Göteborg, Sweden)

Chem. Phys. Lett., 509(4-6) (2011) pp. 134-137.

A Schottky-type model describing Pt²⁺ dissolution and redeposition on Pt nanoparticles in polymer electrolyte fuel cells is presented. The charge transfer is considered to occur near the surface of nanoparticles so that the potential barrier for the reaction is formed by the double-layer potential and the image interaction. With increasing electrode potential, the transfer coefficient for dissolution is found to decrease from 0.6-0.7 down to 0.3-0.4. Its dependence on the effective dielectric constant of the double layer is appreciable while the dependence on the particle size is weak.

V.P. Zhdanov, B. Kasemo* (*Chalmers University of Technology, Göteborg, Sweden)

Physica E, 43(8) (2011) pp. 1486-1489.

The conventional Schottky model describes in the mean-field approximation the electrostatic potential appearing in a doped semiconductor during its flat contact with a metal. More recently, the Schottky model has been used to describe the mean-field potential profile near a metallic nanosphere surrounded by or located on the surface of a semiconductor. The authors present the corresponding results for a metallic nanowire. In these three cases, the shape of the potential profiles and their scalings are very different. In particular, the full width at half maximum of the potential barrier dramatically shrinks if the geometry changes from linear to cylindrical and then to spherical. In addition, the authors scrutinize the effect of the discreteness of the dopant charges on the potential near a metallic nanosphere.

Kinet. Catal., 52(3) (2011) pp. 401-408.

Radically different dependences of the activity of La_1-xSr_xMnO₃ (x = 0-0.5) perovskites in methane oxidation on the degree of substitution of strontium for lanthanum are observed for low and high temperatures. Unsubstituted LaMnO₃ exhibits the highest activity in the temperature range from 300 to 500°C, while the sample with the maximum degree of substitution (La_0.5Sr_0.5MnO₃) shows the highest activity at higher temperatures of 700–900°C. In the low temperature region, the activity of La_1-xSr_xMnO₃ is determined by the amount of weakly bound (overstoichiometric) oxygen, which is formed in cation-deficient lattices and is characterized by a thermal desorption peak with T_max = 705°C. At higher temperatures (800–900°C), the strongly bound oxygen of the catalyst lattice is involved in the formation of the reaction products under both unsteady- and steady-state conditions. As a consequence, the catalytic activity in methane oxidation correlates with the apparent rate constant of oxygen diffusion in the oxide bulk.

Catal. Lett., 141(2) (2011) pp. 322-331.

In this paper a wide range of La_1-xSr_xMnO₃ (x = 0–0.7) perovskites was synthesized by Pechini route, characterized by XRD (including high temperature measurements), XPS, differential dissolution phase analysis, TPR H₂, oxygen exchange and tested in N₂O decomposition at 900°C. At low degree of Sr substitution for La (x ≤ 0.3), high catalytic activity was found for perovskites with hexagonal structure (x = 0.1-0.2) and can be related to fast oxygen mobility caused by the lattice disordering during polymorphic phase transition from the hexagonal to cubic structure. For multiphase samples (x > 0.3) increase of activity and oxygen mobility can be attributed to the formation of the layer structured perovskite - LaSrMnO₄ on the surface.

Kinet. Catal., 52(2) (2011) pp. 305-315.

The adsorption of 1,2-dichloroethane on zeolite HZSM-5 and y-Al₂O₃ at temperatures from 25 to 400°C was studied by Fourier transform IR spectroscopy. The forms of adsorbed 1,2-dichloroethane and the products of its conversion at the Brønsted and Lewis acid sites of catalysts were identified. The kinetics of 1,2-dichloroethane conversion on the surface of catalysts was studied by in situ Fourier transform IR spectroscopy. It was demonstrated that 1,2-dichloroethane was dehydrochlorinated at the Lewis sites of y-Al₂O₃ even at 100°C, whereas the reaction came into play at the Brønsted sites of zeolite HZSM-5 only at 200°C. It was found that, at the Lewis acid sites of catalysts, the resulting vinyl chloride underwent oligomerization with the intermediate formation of a dimer (1,3-dichloro-2-butene), whereas the formation of 1,3-dichloro-2-butene at the Brønsted sites of zeolite HZSM-5 was not observed. The mechanisms of 1,2-dichloroethane conversions at Lewis and Brønsted acid sites were proposed.

Appl. Catal., B, 103(1-2) (2011) pp. 1-10.

This study was devoted to determination of localization of the individual copper species in the pores of ZSM-5 zeolite after post-synthetic zeolite modification by incipient wetness impregnation with CuCl₂ solution followed by hydrolytic polycondensation of the ions in the pores. A series of Cu(n)ZSM-5 samples, where n is the copper concentration varied from 0.5 to 5.0 wt%, were synthesized using this method. A commercial HZSM-5 zeolite having Si/Al = 17 was used for the synthesis of the catalysts. After modification the Cu(n)ZSM-5 samples were dried and calcined in air at 110 and 450°C, respectively. The samples were studied by UV–vis–NIR DR spectroscopy, XRD and by measuring and processing the low-temperature (77 K) adsorption of nitrogen and hydrogen. It was shown for the first time that at the concentration of 1.0 wt% or lower copper was localized in the form of isolated Cu²⁺_Oh cations in the ion-exchange positions in the zeolite micro- and mesopores as well as on oxygen complexes of extraframework aluminum in thin mesopores with D < 3.2 nm in the form of superficial spinel-like structures in octahedral oxygen coordination Cu²⁺_Oh. At the copper concentration above 1.0 wt% linear associates of weakly bound Cu²⁺_Oh ions with unusual orbital ordering were formed in addition to the two forms discussed above. These associates existing in the forms of one- and two-dimensional nanohydroxocompounds were localized partially in the zeolite micropores but mostly in thin mesopores.

The effect of the individual copper species on the catalytic properties of Cu(n)ZSM-5 samples in selective catalytic reduction of NO by propane was also studied. It was found that isolated Cu²⁺_Oh cations in the ion-exchange positions and Cu²⁺_Oh cations localized on the oxygen complexes of extraframework aluminum had the highest catalytic activity in NO SCR by propane. The weakly bound linear associates of Cu²⁺_Oh ions had lower catalytic activity, compared with isolated Cu²⁺_Oh ions. When their amount was high, they caused steric hindrance for contact of the reagents with the more active sites. The Cu²⁺_Oh ion associates were found to transform to nanodispersed Cu₂(OH)₃Cl during catalytic experiments.

J. Mol. Catal. A: Chem., 347(1-2) (2011) pp. 22-27.

Reactivity of oxygen species generated by N₂O decomposition over Fe-ZSM-5 and Fe-Beta zeolites was investigated using oxygen isotopic exchange as test reaction. The generated species are very stable up to 300°C in the absence of the organic traces or residual N₂O in the gas phase. The reactivity of the oxygen species towards organics depends on the size of the organic molecules and their ability to penetrate into the zeolite pores. For example, in case of Fe-ZSM-5 zeolite, the oxygen species react readily with toluene, but stay intact with more bulky 1,3,5-trimethylbenzene.

ChemCatChem, 3(7) (2011) pp. 1143-1145.

Results from a comparative study of the catalytic activity of MoVNb, MoVTe, and MoVNbTe mixed oxides in the gas phase oxidation of ethanol are reported. Multi-component MoVNbTe mixed oxides, analogous to those, which are used in the propane (amm)oxidation), in contrast to three-component MoVNb and MoVTe oxides show exclusive efficiency in selective oxidation of ethanol by molecular oxygen to obtain acetic acid.

ChemCatChem, 3(9) (2011) pp. 1422-1425.

In the present work, the efforts were focused on the role of hydrogen in the catalytic activity of gold supported on TiO₂, Al₂O₃, and SiO₂ matrixes to provide insights into the different profiles of ethanol oxidation.

V.V. Pashkov*, D.V. Golinsky*, I.E. Udras*, E.A. Paukshtis, A.S. Belyi* (*Institute of Hydrocarbons Processing, Omsk, Russia)

Pet. Chem., 51(4) (2011) pp. 286-292.

It has been found that the joint aromatization of C₄ and C₆ alkanes proceeds during the conversion of a butane and hexane mixture on alumina–platinum catalysts. It has been shown that a necessary condition for realization of the joint aromatization is the presence of highly dispersed platinum as ionic species (Pt^σ) and “hard” Lewis acid sites (L_z) of a catalyst. It has been determined that an optimum L_z/Pt^σ ratio for joint conversion reaction of light alkanes is from 1 to 2.

V.V. Zhivonitko*, K.V. Kovtunov*, I.E. Beck, A.B. Ayupov, V.I. Bukhtiyarov, I.V. Koptyug* (*International Tomography Center, Novosibirsk, Russia)

J. Phys. Chem. C, 115(27) (2011) pp. 13386-13391.

Substantial NMR signal enhancements provided by parahydrogen-induced polarization (PHIP) are associated with the ability of a catalyst to incorporate both H atoms of a dihydrogen molecule into the same product molecule. Therefore, PHIP can provide valuable information about the mechanisms and kinetics of catalytic hydrogenation reactions as well as produce hyperpolarized molecules for sensitivity enhancement in NMR. In this work, the PHIP technique was applied to study the structure sensitivity and the support effects on the degree of pairwise H₂ addition in propene hydrogenation over supported platinum catalysts. Four series of Pt catalysts supported on Al₂O₃, SiO₂, ZrO₂, and TiO₂ were examined. A nontrivial dependence of the selectivity toward pairwise H₂ addition on the Pt particle size was found. Its analysis indicates that at least three types of different active sites coexist on the catalysts surface. Among them, the major one is responsible for the nonpairwise H₂ addition to the double bond, whereas pairwise addition can proceed on the other two minor active sites. An explanation of the nature of these active sites is proposed. A substantial increase in the pairwise addition selectivity was found for Pt/TiO₂ catalysts as compared to other catalyst series, possibly due to a strong metal―support interaction taking place even after low temperature catalyst reduction.

Appl. Catal., B, 103(3-4) (2011) pp. 397-403.

Spectroscopic (laser-induced luminescence (LIL) and EPR) and catalytic (ethane hydrogenolysis) techniques were used for characterization of the active sites of Pd/Al₂O₃ catalysts. These techniques have high sensitivity and make it possible to study the catalysts with Pd concentrations as low as 0.02–0.03 wt%. It was found by EPR using spin probes that the electron donor sites of the support are modified by the deposited palladium. It was found by LIL that the Pd deposition has a substantial effect on the state of hydroxyls on the Al₂O₃ surface. The obtained results indicate that at Pd concentrations 0.5 wt% or lower supported Pd does not form PdO phase. Instead, it is stabilized in the form of atomically dispersed ion clusters. The possible role of the Al₂O₃ donor sites in stabilization of such clusters is discussed.

Appl. Catal., A, 401(1-2) (2011) pp. 83-97.

Pd/Al₂O₃ supported catalysts, differed in the initial structural and chemical states of palladium, were examined for the possible existence of self-sustained oscillations in the reaction of CO oxidation under temperature-programmed and isothermal modes using plug flow reactor at ambient pressure and CO and O₂ concentration of 0.2 and 1.0 vol.%, respectively. The supported samples after the action of reaction mixture were characterized using the HRTEM and XPS methods. The catalysts, calcined at relatively low temperatures 450°C, cannot induce the self-sustained oscillation phenomena in the reaction of CO oxidation. The calcination at 800°C yields highly dispersed particles of Pd⁰ and PdO in the catalysts with sizes varying between 2–3 and 10–20 nm, respectively. In this case self-sustained oscillations (SO) of the CO oxidation appeared in the region of middle CO conversions. In the catalyst calcined at 1000°C, PdO is formed as large particles with sizes 20–100 nm. During prolonged self-sustained oscillations under isothermal conditions with varying CO concentrations in the reaction mixture, particles with “core–shell” structures are formed, where the cores are PdO and the shells are a Pd⁰ clusters ordered along a specific direction due to an epitaxy on PdO. Calcination at 1200°C results in the formation of large Pd⁰ particles with sizes ≥200 nm. During prolonged self-sustained oscillations with varying CO concentrations under isothermal conditions, the reaction mixture causes destruction of the above particles to yield palladium particles with core–shell structures; in this case the cores are Pd⁰, and the shells are PdO layers.

E.M. Slavinskaya, R.V. Gulyaev, O.A. Stonkus, A.V. Zadesenets*, P.E. Plyusnin*, Yu.V. Shubin*, S.V. Korenev*, A.S. Ivanova, V.I. Zaikovsky, I.G. Danilova, A.I. Boronin (*Nikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia)

Kinet. Catal., 52(2) (2011) pp. 282-295.

Catalysts containing cerium oxide as a support and platinum and palladium as active components for the low-temperature oxidation of carbon monoxide were studied. The catalysts were synthesized in accordance with original procedures with the use of palladium and platinum complex salts. Regardless of preparation procedure, the samples prepared with the use of only platinum precursors did not exhibit activity at a low temperature because only metal and oxide (PtO, PtO₂) nanoparticles were formed on the surface of CeO₂. Unlike platinum, palladium can be dispersed on the surface of CeO₂ to a maximum extent up to an almost an ionic (atomic) state, and it forms mixed surface phases with cerium oxide. In a mixed palladium-platinum catalyst, the ability of platinum to undergo dispersion under the action of palladium also increased; as a result, a combined surface phase with the formula Pd_xPt_yCeO_2-δ, which exhibits catalytic activity at low temperatures, was formed.

R.V. Gulyaev, L.S. Kibis, O.A. Stonkus, A.V. Zadesenets*, P.E. Plyusnin*, Yu.V. Shubin*, S.V. Korenev*, A.S. Ivanova, E.M. Slavinskaya, V.I. Zaikovsky, I.G. Danilova, A.I. Boronin (*Nikolaev Institute of Inorganic Chemistry, Novosibirsk, Russia)

J. Struct. Chem., 52(suppl.) (2011) pp. 123-136.

Gold-palladium catalysts supported on cerium oxide were synthesized with the double complex salts. X-ray photoelectron spectroscopy (XPS) and other physicochemical methods (TEM, TPR) were used to demonstrate that synthesis of highly active palladium catalysts requires the oxidative treatment stimulating the formation of a catalytically active surface solid solution Pd_xCe_1-xO₂, which is responsible for the low-temperature activity (LTA) in the reaction CO + O₂. In the case of gold catalysts, active sites for the low-temperature oxidation of CO are represented by gold nanoparticles and its cationic interface species. Simultaneous deposition of two metals increases the catalyst LTA due to interaction of both gold and palladium with the support surface to form a Pd_1-xCe_xO₂ solid solution and cationic interface species of palladium and gold on the boundary of Pd-Au alloy particles anchored on the solid solution surface.

A.A. Khassin, T.M. Yurieva, B.M. Weckhuysen** (*Laboratory of Solid State Physics and Magnetism & INPAC, Leuven, Belgium; **Utrecht University, Utrecht, The Netherlands; ***University of Amsterdam, Amsterdam, The Netherlands)

J. Phys. Chem. C, 115(41) (2011) pp. 20175-20191.

In situ X-ray absorption spectroscopy XAFS at the Cu and Zn K-edge has been used to unravel the Cu/Zn interaction and identify the possible active site of Cu-based methanol synthesis catalysts in the Cu/ZnO/SiO₂ ternary system. These highly dispersed silica supported catalysts, whose activity increases sharply as a function of the reduction temperature, were studied calcined, reduced at 200, 300, and 400°C, and for each reduction temperature under passivation/rereduction and methanol synthesis conditions. Results showed that the calcined form consists mainly of a mixed Cu/Zn hydrosilicate that is progressively transformed as the reduction temperature increases into (i) Cu metal particles, (ii) increasingly dispersed ZnO species on SiO₂, and (iii) finally a Zn metallic phase forming segregated bimetallic Cu–Zn α-brass alloy particles. These different structures and Cu/Zn interfaces may correspond to different active phases and activities in methanol synthesis. After reduction at 200 and 300°C, Cu⁰ is likely composing most of the active phase, whereas above 300°C, the sharp increase in the number Zn⁰-based sites formed as a function of the reduction temperature could explain the major role played by this parameter in controlling the activity of these catalysts. The dynamic Cu/Zn interaction as a function of the temperature and gas environment

pointed out in this ternary system may be at the origin of the existence of different and sometimes contradictory models to account for the mechanisms of the methanol synthesis.

J. Catal., 278(1) (2011) pp. 71-77.

Several pure and doped alumina samples were characterized by EPR using spin probes and tested in ethanol dehydration. It was found that the concentrations of the electron acceptor sites and the catalytic activity increased when alumina was modified with chlorides and sulfates. Meanwhile, the number of the electron donor sites decreased. A very good correlation between the concentration of the weak acceptor sites and the catalytic activity of the acid-modified catalysts almost passing through the origin of the coordinates was obtained for all the studied samples. Alumina poisoning with sodium resulted in the decrease in the catalytic activity and the concentration of the weak acceptor sites. Therefore, it appears that the weak acceptor sites tested using anthracene are related to the sites active in the ethanol dehydration reaction.

Appl. Surf. Sci., 257(20) (2011) pp. 8542-8549.

Nanostructured copper (II) oxide was formed on clean copper foil at room temperature using activated oxygen produced by RF discharge. CuO particles of approximately 10-20 nm were observed on the surface by Scanning Tunneling Microscopy (STM). The copper states and oxygen species of the model cupric oxide were studied by means of X-ray Photoelectron Spectroscopy (XPS). These oxide particles demonstrated abnormally high reactivity with carbon monoxide (CO) at temperatures below 100°C. The XPS data showed that the interaction of CO with the nanostructured cupric oxide resulted in reduction of the CuO particles to Cu₂O species. The reactivity of the nanostructured cupric oxide to CO was studied at 80°C using XPS in step-by-step mode. The initial reactivity was estimated to be 5 x 10^-5 and was steadily reduced down to 5 x 10^-9 as the exposure was increased. O1s spectral analysis allowed to propose that the high initial reactivity was caused by the presence of non-lattice oxygen states on the surface of the nanostructured CuO. It was established that reoxidation of the partially reduced nanostructured cupric oxide by molecular oxygen O₂ restored the highly reactive oxygen form on the surface. These results allowed to propose that the nanostructured cupric oxide could be used for low temperature catalytic CO oxidation. Some hypotheses concerning the nature of the non-lattice oxygen species with high reactivity are also discussed.

M.N. Timofeeva, Z. Hasan*, A.Yu. Orlov, V.N. Panchenko, Yu.A. Chesalov, I.E. Soshnikov, Sung H. Jhung* (*Kyungpook National University, Taegu, South Korea)

Appl. Catal., B, 107(1-2) (2011) pp. 197-204.

Fe-containing nickel phosphate molecular sieves (Fe-VSB-5) were hydrothermally synthesized in weak basic conditions under microwave irradiation and characterized by SEM, XRD,

N₂-adsorption/desorption, DRS-UV–vis, and FT-IR spectroscopy using PhCN and CDCl₃ as probe molecules. The catalytic activity of Fe-VSB-5 was tested for the phenol hydroxylation and wet phenol oxidation with H₂O₂. The increase in iron content in Fe-VSB-5 leds to an increase in the reaction rates. The increases in activity can be explained by the role of the Fe species, which increases the generation of radicals. The Fe-VSB-5 samples were stable against the leaching out of Fe ions. The catalytic activity of Fe-VSB-5 was compared to the catalytic activity of traditional Fe-containing materials.

J. Phys. Chem. C, 115(25) (2011) pp. 12554-12559.

In spite of a long investigation history, the low-temperature isotopic exchange in dioxygen taking place without involvement of the catalyst oxygen (R₀ exchange) is still an exotic and poorly understood phenomenon in heterogeneous catalysis. Although very strong bonds are to be cleft in O₂ molecules (118 kcal/mol), over some metal oxides R₀ can be observed even at the temperature of liquid nitrogen. In this work, the authors studied the R₀ exchange over a FeZSM-5 zeolite at 233 K and discovered for the first time a linear dependence of the R₀ rate on the concentration of O^•– radicals (a-oxygen), which identifies a catalytic role of these species. Upon transition to cryogenic temperatures, O^•– species lose the ability to exchange themselves with dioxygen, but start functioning as a principal part of unique active sites capable of catalyzing a very smooth redistribution of the oxygen-oxygen bonds in adsorbed O₂ molecules. Running by a highly concerted mechanism, this remarkable process leads to the R₀ exchange with almost zero activation energy (0.2 kcal/mol). The catalytic role of O^•– radicals well explains all previous results obtained for the R₀ exchange in the literature. Possible models of active sites comprising O^•– species are discussed.

J. Phys. Chem. C, 115(5) (2011) pp. 2155-2161.

Room-temperature oxidation of methane to methanol by a-oxygen is of great mechanistic interest for both conventional and biomimetic oxidation catalysis. This work was carried out using new-generation FeZSM-5 samples that have the O_a concentration of 100 umol/g. This value exceeds 3-15 times the O_a concentration on the earlier studied samples, thus providing more precise quantitative measurements related to the reaction mechanism. Fourier transform infrared spectroscopy data confirmed an earlier conclusion that CH₄ + O_α surface reaction proceeds by the hydrogen abstraction mechanism. This mechanism leads to hydroxy and methoxy groups residing on α-sites. The methanol formation takes place by hydrolysis of (Fe-OCH₃)_α groups at the step of extraction. For the first time dimethyl ether (DME) was identified in the reaction products, its amount comprising 6-7% of the methane reacted. In distinction to methanol, DME is readily extracted both by dry solvents (acetonitrile, tetrahydrofuran, ethanol) and their mixtures with water. A reliable extraction procedure was developed, which provides a 75% recovery of the methane oxidation products (methanol + DME). The missing products are shown to remain on the catalyst surface and can be quantitatively recovered in the form of CO_x at heating the sample. A mechanism involving CH₃^• radicals formed in the H-abstraction step is suggested to explain the reaction stoichiometry CH₄:O_α = 1:1.75 and a deficit of the carbon balance at extraction.

Kinet. Catal., 52(6) (2011) pp. 828-834.

In catalytic two-step n-butene oxidation with dioxygen to methyl ethyl ketone, the first step is the oxidation of n-C₄H₈ with an aqueous solution of Mo–V–P heteropoly acid in the presence of Pd(II) complexes. The kinetics of n-butene oxidation with solutions of H₇PV₄Mo₈O₄₀ (HPA-4) in the presence of the Pd(II) dipicolinate complex (H₂O)Pd^II(dipic) (I), where dipic^2– is the tridentate ligand 2,6-NC₅H₃(COO^–)₂, is studied. Calculation shows that, at the ratio dipic^2– : Pd(II) = 1 : 1, the ligand decreases the redox potential of the Pd(II)/Pd_met system from 0.92 to 0.73–0.77, due to which Pd(II) is stabilized in reduced solutions of HPA-4. The reaction is first-order with respect to n-C₄H₈. Its order with respect to Pd(II) is slightly below unity, and its order with respect to HPA-4 is relatively low (~0.63). The activation energy of but-1-ene oxidation in the temperature range from 40 to 80°C is 49.0 kJ/mol, and that of the oxidation of but-2-ene is 55.6 kJ/mol. The mechanism of the reaction involving the cis-diaqua complex [(H₂O)₂Pd^II(Hdipic)]⁺, which forms reversibly from complex I, is proposed. The reaction rate is shown to increase with an increase in the HPA-4 concentration due to an increase in the acidity of the solution.

V.A. Sadykov, N.N. Sazonova, A.S. Bobin, V.S. Muzykantov, E.L. Gubanova*, G.M. Alikina, A.I. Lukashevich, V.A. Rogov, E.N. Ermakova, E.M. Sadovskaya, N.V. Mezentseva, E.G. Zevak, S.A. Veniaminov, M. Muhler*, C. Mirodatos**, Y. Schuurman**, A.C. van Veen*^,** (*Ruhr-Universität Bochum, Bochum, Germany; **Institut de Recherches sur la Catalyse et L’environnement de Lyon, Villeurbanne Cedex, France)

Catal. Today, 169(1) (2011) pp. 125-137.

Partial oxidation of methane into syngas at short contact times (5–15 ms) was studied in both steady-state and transient modes at temperatures up to 850°C in realistic feeds (CH₄ content up to 20%, CH₄/O₂ = 2) with a minimum impact of mass and heat transfer for structured catalysts carrying Pt/Ln_0.3Ce_0.35Zr_0.35O_2-y (Ln = La, Pr, Gd) as thin layers on walls of corundum channel substrates. Oxygen mobility and reactivity of the active phase were characterized by oxygen isotope heteroexchange, temperature-programmed O₂ desorption and CH₄ reduction, isothermal pulse reduction by methane with wide variation of CH₄ concentrations and TAP pulse studies. Experimental data point towards a selective oxidation of methane into syngas via a direct route with oxygen-assisted methane activation. This mechanistic feature is related to the strong Pt-support interaction stabilizing highly dispersed oxidic Pt species less active in CH₄ and syngas combustion than metallic Pt clusters. Support activates O₂ molecules and supplies active oxygen species to Pt sites. A high rate of oxygen diffusion on the surface and in the bulk of the support and Pt-support oxygen spillover stabilizes Pt in a well dispersed partially oxidized state while preventing coking at high concentrations of CH₄ in the feed.

(*Institut de Recherches sur la Catalyse et L’environnement de Lyon, Villeurbanne Cedex, France)

Catal. Today, 171(1) (2011) pp. 140-149.

The effect of pretreatment and Pt content on the catalytic properties as well as mechanistic features of DR were investigated for structured catalysts comprised of Pt supported on CeO₂-ZrO₂ oxide doped by Pr. Progressive reduction of cationic Pt species by the reaction feed lowers the activity in CH₄ dry reforming while accelerating the reverse water gas shift reaction catalyzed only by Pt(0), which then decreases progressively the H₂/CO ratio in the effluent. This process is counteracted by the mobility of surface oxygen supplying oxygen atoms to reduced Pt centers thus ensuring their reoxidation and generating in parallel surface oxygen vacancies for the dissociation of CO₂.

A mathematical model and software were developed for numerically studying the transients of the complex catalytic reactions. The processing of experimental data was fulfilled taking into account the importance of cationic forms of Pt, reactivity of carbonate complexes coordinated to these cations and oxygen surface/bulk diffusion. A quantitative evaluation of the density of catalyst's active sites and their coverage by reactive species was accomplished and the rates both of the lattice oxygen diffusion and main stages of the catalytic reaction were estimated.

Catal. Today, 164(1) (2011) pp. 227-233.

LnFe_0.7Ni_0.3O_3-δ (Ln = La, Pr, Sm) perovskites synthesized via Pechini method have been studied as catalysts of methane dry reforming (MDR). Effects of pretreatment and type of Ln cation on the structural and redox properties of perovskites and their catalytic performance have been elucidated. The most active catalysts are obtained by keeping perovskites in the reaction feed at high temperatures due to the formation of Ni–Fe alloy particles released from the perovskite lattice and stabilized on its surface. PrFe_0.7Ni_0.3O_3-δ was found to be the most active and stable catalyst due to the optimal composition of segregated Ni–Fe alloy particles and redox properties of oxide matrix.

O.B. Belskaya*^,**, N.N. Leont’eva*, T.I. Gulyaeva*, V.A. Drozdov*^,**, V.P. Doronin*^,**, V.I. Zaikovsky, V.A. Likholobov* (*Institute of Hydrocarbons

Processing, Omsk, Russia; **Omsk State Technical University, Omsk, Russia)

Kinet. Catal., 52(5) (2011) pp. 761-769.

A layered aluminum–magnesium hydroxide of the hydrotalcite type containing interlayer carbonate counterions (HT-CO₃) and activated hydrotalcite containing interlayer OH^– ions (HT-OH) were studied for the subsequent use as the precursors of supports for platinum catalysts. It was found that the nature of an interlayer anion in the composition of an aluminum–magnesium layered hydroxide is an important factor affecting both the formation of the oxide support and its texture characteristics. The replacement of the interlayer anion by OH^– resulted in changes in the structural parameters of the initial double hydroxide: a decrease in the interlayer distance with the retention of the Mg/Al ratio and an increase in the imperfection of the layered material. X-ray diffraction studies in the temperature range of 30– 900°C showed that HT-OH is characterized by the ability to form low-temperature spinel at 375°C. As a result, two types of aluminum–magnesium oxide supports, which were characterized by different pore space organizations at the same Mg : Al ratio, were obtained from the given layered hydroxides.

M.O. Kazakov*, A.V. Lavrenov*, I.G. Danilova, O.B. Belskaya*, V.K. Duplyakin* (*Institute of Hydrocarbons Processing, Omsk, Russia)

Kinet. Catal., 52(4) (2011) pp. 573-578.

The acidic and hydrogenating of Pt/SO₄^2-–ZrO₂–Al₂O₃ samples containing from 18.8 to 67.8 wt% Al₂O₃ as a support constituent were studied by the IR spectroscopy of adsorbed CO and pyridine, and the model reactions of n-heptane and cyclohexane isomerization on these catalysts were examined. The total catalyst activity in the conversion of n-heptane decreased with the concentration of Al₂O₃; this manifested itself in an increase in the temperature of 50% n-heptane conversion from 112 to 266°C and in an increase in the selectivity of isomerization to 94.2%. In this case, the maximum yield of isoheptanes was 47.1 wt%, which was reached on a sample whose support contained 67.8 wt% Al₂O₃. A maximum yield (69.6 wt%) and selectivity (93.7%) for methylcyclopentane formation from cyclohexane were also reached on the above catalyst sample. This can be explained by lower concentrations of Lewis and Bronsted acid sites in the Pt/SO₄^2-–ZrO₂–Al₂O₃ system, as compared with those in Pt/SO₄^2-–ZrO₂. The experimental results allowed to make a preliminary conclusion that the Pt/SO₄^2-–ZrO₂–Al₂O₃ catalyst whose support contains 67.8 wt% Al₂O₃ is promising for use in the selective hydroisomerization of benzene-containing gasoline fractions in the thermodynamically favorable process temperature range of 250–300°C.

O.B. Belskaya*, T.I. Gulyaeva*, N.N. Leont’eva*, V.I. Zaikovsky, T.V. Larina, T.V. Kireeva*, V.P. Doronin*, V.A. Likholobov* (*Institute of Hydrocarbons Processing, Omsk, Russia)

Kinet. Catal., 52(6) (2011) pp. 876-885.

The interaction of aqueous H₂PtCl₆ solutions with hydrotalcite-type aluminum–magnesium

hydroxides differing in the nature of their interlayer anion is reported. In the case of CO₃^2- as the interlayer anion, the introduction of the platinum(IV) chloro complex does exerts no significant effect on the structural properties of the support, on its thermal decomposition dynamics, and on the textural characteristics of the resulting oxide phase. The binding of the platinum complexes to “activated hydrotalcite” with interlayer OH^– anions increases the interplanar spacing and enhances the thermal stability of the layered structure. This is accompanied by marked changes in textural characteristics of the material, leading to the formation of a nearly monodisperse mixed oxide phase. In the Pt/MgAlO_x samples obtained by reductive treatment, a considerable proportion of platinum is in the form of planar particles, and this corroborates the hypothesis that the metal complex at the sorption stage is mainly localized in the interlayer space of this support. Platinum binds to the support as chloro complexes via rapid anion exchange, and these bound platinum species are characterized by a higher reduction temperature.

V.I. Simagina, O.V. Komova, A.M. Ozerova, O.V. Netskina, G.V. Odegova, D.G. Kellerman*, O.A. Bulavchenko, A.V. Ishchenko (*Institute of Solid State Chemistry, Yekaterinburg, Russia)

Appl. Catal., A, 394(1-2) (2011) pp. 86-92.

The catalytic properties of Co₃O₄ in NaBH₄ and NH₃BH₃ hydrolysis have been studied. Experiments were carried out at 20–40°C using 0.12 M hydride solution. According to magnetic susceptibility measurements, FTIR, XRD, and TEM studies, Co₃O₄ is reduced to the ferromagnetic catalytically active Co₂B phase under the action of the NaBH₄ hydrolysis reaction medium. A correlation was found between the content of the cobalt boride phase formed in situ and catalyst activity. The reduction of Co₃O₄ in NH₃BH₃ proceeds at slower rate than in NaBH₄. The addition to a solution of NH₃BH₃ of even a small amount of NaBH₄ increases considerably the reduction rate of Co₃O₄. Using a Co₃O₄-based precursor instead of the widely used CoCl₂ leads to the formation of a stable catalytically active phase of cobalt boride.

Inorg. Mater., 47(10) (2011) pp. 1101-1107.

In the presence of anatase, the thermal decomposition of ammonia borane (AB) begins at a lower temperature, which enables AB dehydrogenation at a temperature as low as 80°C. The reduction in the AB decomposition temperature depends on the AB content of the mixture. In situ IR spectroscopy data demonstrate that, in the presence of TiO₂, the structural destabilization of AB occurs during heating and is accompanied by the formation of an oxygen-containing boron phase and partial reduction of the titania, which is supported by diffuse reflectance spectroscopy data.

Kinet. Catal., 52(1) (2011) pp. 104-110.

The phase composition and microstructure of La_1-xCa_xMnO₃ (x = 0–1) materials prepared by the Pechini method from polymer-salt stocks were studied after testing these materials in methane oxidation. According to X-ray diffraction data, the reaction medium causes no significant changes in the samples, while high-resolution transmission electron microscopy indicates that the x > 0.3 samples are

unstable. Under the action of the reaction medium, the perovskite structure of these samples undergoes partial decomposition accompanied by the formation of planar defects having a lower manganese content. The number and degree of segregation of these defects increase with increasing calcium content. The calcium oxide and manganese oxide phases as segregated nanoparticles are observed on the particle surface. These changes are caused by the decrease in the oxygen content of the manganites under the action of the reaction medium (T, PO₂), by the formation of vacancies, and by the variation of the charge of the manganese cations, as well as by the charge ordering tendency of the manganese cations. Therefore, the observed changes in catalytic activity under the action of the reaction medium for x > 0.3 can be due to perovskite decomposition accompanied by the formation of planar defects, the release of the manganese oxide and calcium oxide phases, and their subsequent sintering.

React. Kinet. Mech. Catal., 103(2) (2011) pp. 261-266.

The identity of surface silver hydroxides produced by hydrogenation or hydration of surface silver oxide was demonstrated. A two-route mechanism of hydrogen interaction with oxygen adsorbed on silver was suggested. The first route includes two consecutive-parallel steps: formation of adsorbed hydroxyl groups and their interaction with hydrogen; the second route consists of two consecutive steps: formation of adsorbed hydroxyl groups and their disproportionation yielding water and adsorbed oxygen.

V.A. Likholobov*, L.G. P’yanova*, A.I. Boronin, S.V. Koshcheev, A.N. Salanov, O.N. Baklanova*, O.A. Knyazheva*, A.V. Veselovskaya* (*Institute of Hydrocarbons Processing, Omsk, Russia)

Prot. Met. Phys. Chem. Surf., 47(2) (2011) pp. 181-190.

The composition and properties of functional groups on the surface of carbon sorbents modified with aqueous solutions of aminocaproic acid of different concentrations were studied using physicochemical analysis methods including: acid-base titration, the Kjeldahl method, scanning electron microscopy, X-ray microanalysis, and X-ray photoelectron spectroscopy. The initial carbon sorbent was shown to have almost no functional groups on its surface. It was ascertained that the surface functionalization of carbon sorbent results in a change in microstructure and an increase in the amount of oxygen- and nitrogen-containing groups with increasing concentration of the modifying agent followed by its further polycondensation on the surface. According to the XPS data, the formation of the bond between aminocaproic acid and the carbon surface of sorbents occurs via a carboxylic group.

Kinet. Catal., 52(5) (2011) pp. 756-760.

Nitric oxide adsorption at 300–500 K on gold particles supported on an alumina film has been investigated for the first time by in situ X-ray photoelectron spectroscopy. Two nitrogen-containing adsorption species can