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991.
P. Y. Zhu 《Il Nuovo Cimento C》1991,14(3):263-283
Summary The effective-medium approximation is applied to investigate scattering from a half-space of randomly and densely distributed
discrete scatterers. Starting from vector wave equations, an approximation, called effective-medium Born approximation, a
particular way, treating Green's functions, and special coordinates, of which the origin is set at the field point, are used
to calculate the bistatic- and back-scatterings. An analytic solution of backscattering with closed form is obtained and it
shows a depolarization effect. The theoretical results are in good agreement with the experimental measurements in the cases
of snow, multi- and first-year sea-ice. The root product ratio of polarization to depolarization in backscattering is equal
to 8; this result constitutes a law about polarized scattering phenomena in the nature. 相似文献
992.
993.
A. A. Maksimenko I. D. Sadekov A. G. Maslakov O. E. Kompan A. I. Yanovskii Yu. T. Struchkov V. I. Minkin 《Journal of Structural Chemistry》1991,32(3):404-405
Scientific-Research Institute of Physical and Organic Chemistry, Rostov State University. A. N. Nesmeyanov Institute of Heteroorganic Compounds, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 32, No. 3, pp. 104–106, May–June, 1991. 相似文献
994.
995.
Olaf Steinbach 《Numerische Mathematik》2002,90(4):775-786
Summary. In this paper we investigate a stability estimate needed in hybrid finite and boundary element methods, especially in hybrid
coupled domain decomposition methods including mortar finite elements. This stability estimate is equivalent to the stability
of a generalized projection in certain Sobolev spaces. Using piecewise linear trial spaces and appropriate piecewise constant test spaces,
the stability of the generalized projection is proved assuming some mesh conditions locally.
Received April 11, 2000 / Revised version received February 15, 2001 / Published online July 25, 2001 相似文献
996.
997.
998.
Institute of Mechanics, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Prikladnaya Mekhanika, Vol. 27, No. 1, pp. 50–55, January, 1991. 相似文献
999.
Hydrogenation and dehydrogenation of the Nd16Fe76B8 magnet are studied by X-ray diffraction analysis (XRD) and Mössbauer spectroscopy. The results of the samples treated under different hydrogen gas pressures at different temperatures are discussed. A special hydrogenation-dehydrogenation treatment of the Nd?Fe?B magnet cast can produce excellent isotropic magnet powders and the treated sample has passed a hydrogenation-disproportionation-recombination process. 相似文献
1000.
A study is made of the laws governing high-temperature creep and the evolution of the substructure in dispersion-hardened
alloy Ni — 3 vol. % HfO2 during its free annealing and creep. The polygonized substructure was formed in the alloy prior to annealing. An analysis
is made of structural transformations at different structural levels and the mechanism of high-temperature creep in the alloy.
Institute of the Physics of Strength and Materials Science, Siberian Branch of the Russian Academy of Sciences. All-Republic
Engineering-Technical Center, Siberian Branch of the Russian Academy of Sciences. Translated from Izvestiya Vysshikh Uchebnykh
Zavedenii, Fizika, No. 3, pp. 83–89, March, 1998. 相似文献