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171.
172.
C. Dionisi R. Armenteros J. Diaz Ph. Gavillet J.B. Gay A. Gurtu R.J. Hemingway M. Mazzucato P. Trepagnier R. Blokzijl G.G.G. Massaro B. Jongejans J. Engelen J.J. Timmermans R.T. Van De Walle B. Foster P.R. Lamb W.L. McDowell 《Physics letters. [Part B]》1978,78(1):154-157
Evidence is presented for an I = 1 enhancement observed in the reactions K?p→Λ(Σ)K01K±π? at inciden momentum. The mass and width of the proposed new Y1 are, respectively, (1553 ± 7) MeV) and (80 ± 30) MeV. A decay branching ratio is also obtained. 相似文献
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174.
R. Nacasch Ch. Defoix L. Dobrzynski P.Ladron de Guevara R. Raghavan M. Aguilar-Benitez J. Diaz A. Ferrando E. Gil J.A. Rubio F. Barreiro A. Gurtu L. Montanet A.M. Cooper S.N. Ganguli P.K. Malhotra A. Subramanian 《Nuclear Physics B》1978,135(2):203-223
In this paper we have investigated the properties of the D(1285) and E(1420) meson resonances using the five-body annihilation channels obtained in a large statistics experiment (28 events/μb). The analysis favours the 1+ spin-parity assignment for the D(1285) meson. The dominant decay mode of the D(1285) into is found to be δ(970)π. The situation concerning the E(1420) meson remains confused although not inconsistent with previous analyses. Partial cross sections on resonance production are also presented. 相似文献
175.
F.M. Fernández C.G. Diaz 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2001,15(1):41-46
We show that algebraic approximants prove suitable for the summation of the perturbation series for the eigenvalues of periodic
problems. Appropriate algebraic approximants constructed from the perturbation series for a given eigenvalue provide information
about other eigenvalues connected with the chosen one by branch points in the complex plane. Such approximants also give those
branch points with remarkable accuracy. We choose Mathieu's equation as illustrative example.
Received 6 December 2000 相似文献
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In this paper, we consider the equation x 2?L n x y+(?1) n y 2 = ±5 r and determine the values of n for which the equation has positive integer solutions x and y. Moreover, we give all positive integer solutions of the equation x 2?L n x y+(?1) n y 2 = ±5 r when the equation has positive integer solutions. 相似文献
179.
Maria Ortencia Gonzalez Diaz Salvador Lopez Morales Ronan Le Lagadec Larissa Alexandrova 《Journal of polymer science. Part A, Polymer chemistry》2011,49(21):4562-4577
Cationic coordinatively saturated complexes of ruthenium(II), [Ru(o‐C6H4‐2‐py)(phen)(MeCN)2]+, bearing different counterions of PF6? and Cl? have been used in the radical polymerization of 2‐hydroxyethyl methacrylate in protic media and acetone under homogeneous conditions. Exchange of PF6? by Cl? increases the solubility of the complex in water. Both complexes led to the fast polymerization under mild conditions, but control was achieved only in methanol and acetone and was better for the complex with Cl?. The polymerization accelerated in aqueous media and proceeded to a high conversion even with a monomer/catalyst = 2000/1, but without control. Polymerization mediated by complex bearing Cl? was slower in protic solvents but faster in acetone and always resulted in lower molecular weight polymers. Thus, the nature of the anion strongly affected the catalytic activity of the complexes and may serve as way of fine‐tuning the catalytic properties. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
180.