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971.
57Fe Mössbauer measurements are reported for the series K x Ba1?x Fe2S3, x ≤ 0.3, at temperatures between 4.2 K ≤ T ≤ 294 K. A decrease of the Debye temperature from 435 to 405 K with x, indicates a weakening of the stiffness of the Fe sublattice. The ordering temperatures, taken from the appearance of magnetic hyperfine splitting in the spectra, are approximately 40 K lower for x ≥ 0.1. The values of the centre shift and the small temperature dependence of the quadrupole splitting strongly supports that similar to the border compound BaFe2S3 also the K containing samples should be characterised as mixed valence compounds. 相似文献
972.
J. Giovinazzo B. Blank C. Borcea M. Chartier S. Czajkowski G. de France R. Grzywacz Z. Janas M. Lewitowicz F. de Oliveira Santos M. Pfützner M.S. Pravikoff J.C. Thomas 《The European Physical Journal A - Hadrons and Nuclei》2001,11(3):247-249
In an experiment at the SISSI/LISE3 facility of GANIL, the most proton-rich zinc isotopes 55,56Zn have been observed for the first time. The experiment was performed using a high-intensity 58Ni beam at 74.5 MeV/nucleon impinging on a nickel target. The identification of 55,56Zn opens the way to 54Zn, a good candidate for two-proton radioactivity according to theoretical predictions.
Received: 31 October 2000 / Accepted: 9 November 2000 相似文献
973.
974.
Tadashi Sugiyama 《Geometriae Dedicata》2007,125(1):53-61
In this paper, we characterize of totally geodesic Kähler immersions by extrinsic shapes of some curves having points of order 2. 相似文献
975.
Tanaka H. Sawai S. Morimoto K. Hisano K. 《Journal of Thermal Analysis and Calorimetry》2001,64(3):867-872
The hemispherical total emissivity of partially stabilized zirconia has been obtained by a spectral analysis of the normal
emission spectra between 400–850 K. Thermal conductivity was evaluated with this emissivity and temperature gradient in the
sample. Effects of the scattering of the radiation in a ceramic sample are also investigated. In addition, specific heat capacity
was measured by thermal radiation calorimetry. Current results are compared with those reported for tetragonal zirconia with
the same yttria content and for monoclinic phase.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
976.
The Fu?ík spectrum for systems of second order ordinary differential equations with Dirichlet or Neumann boundary values is considered: it is proved that the Fu?ík spectrum consists of global C1 surfaces, and that through each eigenvalue of the linear system pass exactly two of these surfaces. Further qualitative, asymptotic and symmetry properties of these spectral surfaces are given. Finally, related problems with nonlinearities which cross asymptotically some eigenvalues, as well as linear-superlinear systems are studied. 相似文献
977.
Daniel Levin 《Annals of Global Analysis and Geometry》2006,29(4):313-322
We obtain a bound for the bottom of the negative spectrum of Schrödinger operators on weighted Riemannian manifolds in terms of F-Sobolev inequalities. Also, we show how an estimate for the first negative eigenvalue implies the F-Sobolev inequality. 相似文献
978.
A class of almost contact metric structures generalizing those of quasi-Sasakian and trans-Sasakian structures is introduced and studied. Its subclass consisting of normal structures locally conformal to quasi-Sasakian structures is investigated in detail. 相似文献
979.
S. I. Serdyukova 《Computational Mathematics and Mathematical Physics》2007,47(5):829-842
A numerical analytical algorithm is developed for calculating the coefficients of a discrete two-dimensional elliptic equation from given eigenvalues and certain symmetry conditions imposed on the basis eigenfunctions. 相似文献
980.