40 research outputs found

    Effect of atmospheric-pressure plasma jet on normal and tumor cells in vitro

    Get PDF
    The purpose of this work is to investigate the effect of low-temperature plasma on tumor and normal cells. As a result of in vitro experiments, plasma-exposed tumor and normal cells demonstrate several effects such as cell detachment, apoptosis or necrosis according to cell type and exposure parameters (power, time of exposure, frequency). In experiments, the inhibition of tumor cell growth was observed up to 70% on the 5th day after exposure. The effect of gas discharge plasma on normal cells was the opposite, and by 5 days there was a stimulation of cell proliferation. The obtained data demonstrate the prospects of using this atmospheric-pressure plasma jet in biomedical research aimed at the treatment of cancer

    Manganese catalysts to obtain olefins from C1-C4 alkanes

    Get PDF
    Oxidative transformations of C1-C4 alkanes into olefins on oxide manganese catalysts were under study. We also studied oxidative coupling of methane (OCM) into ethylene on deposited and applied on the silicon dioxide catalysts. We studied the influence of chemical composition of catalyst and promotors on the OCM. Adding a little amount of ethane and propane hydrocarbons to methane allows increasing the concentration of ethylene in gases and significantly increasing productivity in ethylene. The study also shows the impact of the amount of manganese and promotors applied on SiO2 on the yield of olefins during the conversion of C3-C4 alkanes

    Phase-Space Volume of Regions of Trapped Motion: Multiple Ring Components and Arcs

    Full text link
    The phase--space volume of regions of regular or trapped motion, for bounded or scattering systems with two degrees of freedom respectively, displays universal properties. In particular, sudden reductions in the phase-space volume or gaps are observed at specific values of the parameter which tunes the dynamics; these locations are approximated by the stability resonances. The latter are defined by a resonant condition on the stability exponents of a central linearly stable periodic orbit. We show that, for more than two degrees of freedom, these resonances can be excited opening up gaps, which effectively separate and reduce the regions of trapped motion in phase space. Using the scattering approach to narrow rings and a billiard system as example, we demonstrate that this mechanism yields rings with two or more components. Arcs are also obtained, specifically when an additional (mean-motion) resonance condition is met. We obtain a complete representation of the phase-space volume occupied by the regions of trapped motion.Comment: 19 pages, 17 figure

    On the superintegrable Richelot systems

    Full text link
    We introduce the Richelot class of superintegrable systems in N-dimensions whose n<=N equations of motion coincide with the Abel equations on n-1 genus hyperellipic curve. The corresponding additional integrals of motion are the second order polynomials of momenta and multiseparability of the Richelot superintegrable systems is related with classical theory of covers of the hyperelliptic curves.Comment: 13 pages, a talk given at the Conference "Symmetry Methods in Physics" devoted to the memory of Professor Y.F.Smirnov, July 6-9, 200

    On the Hamiltonian formulation of the trigonometric spin Ruijsenaars-Schneider system

    Get PDF
    We suggest a Hamiltonian formulation for the spin Ruijsenaars–Schneider system in the trigonometric case. Within this interpretation, the phase space is obtained by a quasi-Hamiltonian reduction performed on (the cotangent bundle to) a representation space of a framed Jordan quiver. For arbitrary quivers, analogous varieties were introduced by Crawley-Boevey and Shaw, and their interpretation as quasi-Hamiltonian quotients was given by Van den Bergh. Using Van den Bergh’s formalism, we construct commuting Hamiltonian functions on the phase space and identify one of the flows with the spin Ruijsenaars–Schneider system. We then calculate all the Poisson brackets between local coordinates, thus answering an old question of Arutyunov and Frolov. We also construct a complete set of commuting Hamiltonians and integrate all the flows explicitly
    corecore