Room temperature Ni-catalyzed reduction of aryl tosylates by borane hydrides

Mild Ni-catalyzed homogeneous reductions of aryl tosylates are described for the first time. The catalytic system Ni(PPh₃)₂Cl₂ and PCy₃ is shown to be general for hydrogenolysis of a wide range of tosylates, including hindered, deactivated, heterocyclic, and bifunctional examples.     

Chlorination of aromatic substrates catalyzed by the phthalocyanine complexes

The chlorination of benzene, toluene, and o-xylene with molecular chlorine in the presence of the phthalocyanine complexes of different structures was studied. The transformations of the catalysts during the reaction were investigated. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1644–1647, August, 2008.     

Risk and quality control in a supply chain: competitive and collaborative approaches

This paper provides a quantitative and comparative economic and risk approach to strategic quality control in a supply chain, consisting of one supplier and one producer, using a random payoff game. Such a game is first solved in a risk-neutral framework by assuming that both parties are competing with each other. We show in this case that there may be an interior solution to the inspection game. A similar analysis under a collaborative framework is shown to be trivial and not practical, with a solution to the inspection game being an ‘all or nothing’ solution to one or both the parties involved. For these reasons, the sampling random payoff game is transformed into a Neyman–Pearson risk constraints game, where the parties minimize the expected costs subject to a set of Neyman–Pearson risk (type I and type II) constraints. In this case, the number of potential equilibria can be large. A number of such solutions are developed and a practical (convex) approach is suggested by providing an interior (partial sampling) solution for the collaborative case. Numerical examples are developed to demonstrate the procedure used. Thus, unlike theoretical approaches to the solution of strategic quality control random payoff games, the approach we construct is both practical and consistent with the statistical risk Neyman–Pearson approach.     

Ghost-matter mixing and feigenbaum universality in string theory

Branelike vertex operators, defining backgrounds with ghost-matter mixing in Neveu-Schwarz-Ramond superstring theory, play an important role in a world-sheet formulation of D branes and M theory, being creation operators for extended objects in the second quantized formalism. We show that the dilaton beta function in ghost-matter mixing backgrounds becomes stochastic. The renormalization group (RG) equations in ghost-matter mixing backgrounds lead to non-Markovian Fokker-Planck equations whose solutions describe superstrings in curved spacetimes with branelike metrics. We show that the Feigenbaum universality constant δ=4.669 ..., describing transitions from order to chaos in a huge variety of dynamical systems, appears analytically in these RG equations. We find that the appearance of this constant is related to the scaling of relative spacetime curvatures at fixed points of the RG flow. In this picture, the fixed points correspond to the period doubling of Feigenbaum iterational schemes.

     

Structure of minimizers in linear-quadratic Bolza problems of optimal control

In this paper, we study intersections of extremals in a linear-quadratic Bolza problem of optimal control. The structure of the inter-sections is described. We show that this structure implies the semipositive definiteness of the quadratic cost functional. In addition, we derive necessary and sufficient conditions for the existence of minimizers.     

Propagation of electromagnetic waves in the earth-ionosphere waveguide with a gradual periodic inhomogeneity of the ionospheric upper-boundary impedance

We study the influence of a gradually inhomogeneous periodic disturbance of the upper-wall impedance of a plane Earth-Ionosphere waveguide on the radiation of a vertical electric dipole immersed in the waveguide channel. We consider the case where the disturbance amplitude is commensurable with the undisturbed value of the impedance. An expression is obtained for the Hertz potential when the source and the observation point are located at the lower wall of the waveguide. Radiophysical Research Institute, Nizhny Novgorod, Russia. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 41, No. 3, pp. 374–383, March, 1998.     

Mechanism of breakdown development in a gas in a subthreshold HF field

The development of a breakdown wave in subthreshold HF fields is considered for the condition that the field energy density exceed the plasma energy density E²/4 > nT. It is shown that the breakdown wave propagation mechanism is controlled by HF diffusion with a coefficient _iE²/4en. A model of breakdown development along the direction of the linear field polarization is constructed on the basis of this mechanism.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 55–60, August, 1989.     

Conducting electrically active films obtained by the electrochemical oxidation of aniline in molten electrolytes and concentrated hydrochloric acid

The feasibility of obtaining electrically conducting and active films by the electropolymerization of aniline in butylpyridinium tetrachloroaluminate or hexachlorodialuminate as the medium has been demonstrated. Identical voltamperometric characteristics with a potential peak of 0.5 V were found in these films and the compound formed upon the electrochemical polymerization of aniline in 20% hydrochloric acid.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 212–214, January, 1991.