Contemporary status of the OPERA experiment for detecting νμ → ντ oscillations in a νμ beam

The first results of the physical stage of the OPERA experiment in 2007, when observation of oscillations of gv_μ into gv_τ started, are discussed. Thirty eight events related to neutrino interactions in emulsion blocks (bricks) are found. The underground muon spectrum and the μ⁺/μ^? ratio are obtained. The results of using detachable emulsion packs (changeable sheets) and accuracy of predictions of neutrino interaction vertices in emulsion layers are discussed. The results of the hardware and software upgrade of the automatic emulsion scanning system PAVIKOM are reported.     

On a 2 + 1-dimensional Darboux system: Integrable and geometric connections

It is shown that a novel 2 + 1-dimensional system recently introduced by Konopelchenko and Rogers contains as a specialization the Zakharov-Manakov matrix triad system. The latter, in turn, in its scalar version yields a classical system investigated by Darboux in connection with conjugate coordinate systems. This Darboux system, in a 1 + 1-dimensional reduction, turns out to be connected to the self-induced transparency equations. Here, geometric aspects of the 2 + 1-dimensional Darboux systems are recorded.     

Synthesis of a Copper-Containing Catalyst for Electrocatalytic Oxidation of Volatile Organic Compounds

The synthesis of a copper-containing catalyst for electrocatalytic oxidation of acetone in exhaust gases was studied. Data on the electrocatalytic oxidation of acetone were analyzed in relation to the CuO content.     

Scanning electron microscopic study of an industrial catalyst for ammonia synthesis

The surface topography and elemental composition of the near-surface layers of a reduced passivated catalyst for ammonia synthesis have been studied on a scanning electron microscope in the initial state and after high-temperature oxygen treatment as well as removal of the alkali promoter.

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Faddeev eigenfunctions for two-dimensional Schrödinger operators via the Moutard transformation

We demonstrate how the Moutard transformation of two-dimensional Schrödinger operators acts on the Faddeev eigenfunctions on the zero-energy level and present some explicitly computed examples of such eigenfunctions for smooth rapidly decaying potentials of operators with a nontrivial kernel and for deformed potentials corresponding to blowup solutions of the Novikov-Veselov equation.     

Global comparison of finite-dimensional reduction schemes in smooth variational problems

A new criterion for global smooth equivalence of a pair of key functions corresponding to a smooth functional in the calculus of variations for a given pair of finite-dimensional reduction schemes is established. The statement is presented in abstract form (we consider a functional on a Banach space with a Fredholm gradient). The main condition is the possibility to deform the reduction schemes into each other preserving the coercivity of the key functions. As a corollary, we obtain the theorem concerning global smooth equivalence of the key functions calculated by the Lyapunov-Schmidt and Morse-Bott reduction schemes in the two-point boundary value problem for a natural mechanical system of sufficiently general form. Translated fromMatematicheskie Zametki, Vol. 67, No. 5, pp. 745–754, May, 2000.     

Redox Reaction of the Pd0 Complex Bearing the Trost Ligand with meso‐Cycloalkene‐1,4‐biscarbonates Leading to a Diamidato PdII Complex and 1,3‐Cycloalkadienes: Enantioselective Desymmetrization Versus Catalyst Deactivation

The Pd⁰ complex 1 that bears the Trost ligand 2 undergoes a facile redox reaction with 1,4‐biscarbonates 5 b – d and rac‐ 22 under formation of the diamidato–Pd^II complex 7 and the corresponding 1,3‐cycloalkadienes 8 b – d . The redox deactivation of complex 1 was the dominating pathway in the reaction of 5 b – d with HCO₃^? at room temperature. However, at 0 °C the six‐membered biscarbonate 5 b , catalytic amounts of complex 1 , and HCO₃^? mainly reacted in an allylic alkylation, which led to a highly selective desymmetrization of the substrate and gave alcohol 6 b with ≥99 % ee in 66 % yield. An increase of the catalyst loading in the reaction of 5 b with 1 and HCO₃^? afforded the bicyclic carbonate 12 b (96 % ee, 92 %). Formation of carbonate 12 b involves two consecutive inter‐ and intramolecular substitution reactions of the π‐allyl–Pd^II complexes 16 b and 18 b , respectively, with O‐nucleophiles and presumably proceeds through the hydrogen carbonate 17 b as key intermediate. The intermediate formation of 17 b is also indicated by the conversion of alcohol rac‐ 6 b to carbonate 12 b upon treatment with HCO₃^? and 1 . The Pd⁰‐catalyzed desymmetrization of 5 b with formation of 12 b and its hydrolysis allow an efficient enantioselective synthesis of diol 13 b . The reaction of the seven‐membered biscarbonate 5 c with ent‐ 1 and HCO₃^? afforded carbonate ent‐ 12 c (99 % ee, 39 %). The Pd⁰ complex 1 is stable in solution and suffers no intramolecular redox reaction with formation of complex 7 and dihydrogen as recently claimed for the similar Pd⁰ complex 9 . Instead, complex 1 is rapidly oxidized by dioxygen to give the stable Pd^II complex 7 . Thus, formation of the Pd^II complex 10 from 9 was most likely due to an oxidation by dioxygen. Oxidative workup (air) of the reaction mixture stemming from the desymmetrization of 5 c catalyzed by 1 gave the Pd^II complex 7 in high yield besides carbonate 12 c .     

Simulation of the electrocatalytic oxidation of acetone in a fixed catalyst bed

Catalytic oxidation of acetone on samples of a copper-containing catalyst with an ac electric field applied to the catalyst bed was simulated. The distribution of temperature across the catalyst bed was studied at varied delivered specific electric power, and kinetic parameters of the catalyst samples were determined.