64,798 research outputs found

    Boundary Harnack estimates in slit domains and applications to thin free boundary problems

    Full text link
    We provide a higher order boundary Harnack inequality for harmonic functions in slit domains. As a corollary we obtain the CC^\infty regularity of the free boundary in the Signorini problem near non-degenerate points

    The Voltammetric Study of the Reduction of Tetraalkylammonium Perchlorate by Fe(TPP)\u3csup\u3e2-\u3c/sup\u3e

    Get PDF
    Tetraalkylammonium ions react with Fe(TPP)2− to form Fe(TPP)(R)− and trialkylamine. The tetrabutylammonium cation was verified to be the source of the alkyl group in the product, Fe(TPP)(R)−, by using (1H5C2)3(2H5C2)N− as the cation and 2H NMR. The reaction of Fe(TPP)2− with Bu4N− was monitored by cyclic voltammetry and thin layer spectroelectrochemistry. The activation parameters were measured, and were most consistent with an electron transfer (ET) mechanism. The rate of the reaction of tetramethyl and tetraethylammonium ions with Fe(TPP)2− was also examined. The rate constant decreased significantly as the carbon chain length decreased, which was also consistent with an ET mechanism

    The two membranes problem for different operators

    Get PDF
    We study the two membranes problem for different operators, possibly nonlocal. We prove a general result about the H\"older continuity of the solutions and we develop a viscosity solution approach to this problem. Then we obtain C1,γC^{1,\gamma} regularity of the solutions provided that the orders of the two operators are different. In the special case when one operator coincides with the fractional Laplacian, we obtain the optimal regularity and a characterization of the free boundary

    Regularity in a one-phase free boundary problem for the fractional Laplacian

    Full text link
    For a one-phase free boundary problem involving a fractional Laplacian, we prove that "flat free boundaries" are C1,αC^{1,\alpha}. We recover the regularity results of Caffarelli for viscosity solutions of the classical Bernoulli-type free boundary problem with the standard Laplacian.Comment: Corrected some typo

    Meson decay in a corrected 30P3^P_0 model

    Full text link
    Extensively applied to both light and heavy meson decay and standing as one of the most successful strong decay models is the 30P3^P_0 model, in which qqˉq\bar{q} pair production is the dominant mechanism. The pair production can be obtained from the non-relativistic limit of a microscopic interaction Hamiltonian involving Dirac quark fields. The evaluation of the decay amplitude can be performed by a diagrammatic technique for drawing quark lines. In this paper we use an alternative approach which consists in a mapping technique, the Fock-Tani formalism, in order to obtain an effective Hamiltonian starting from same microscopic interaction. An additional effect is manifest in this formalism associated to the extended nature of mesons: bound-state corrections. A corrected 30P3^P_0 is obtained and applied, as an example, to b1ωπb_{1}\to\omega\pi and a1ρπa_{1}\to\rho\pi decays.Comment: 3 figures. To appear in Physical Review
    corecore