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91.
Montgomery and Vaughan improved a theorem of Erd?s and Fuchs for an arbitrary sequence. Sárközy extended this theorem of Erd?s and Fuchs for two arbitrary sequences which are "near" in a certain sense. Using the idea of Jurkat (differentiation of the generating function), we will extend similarly the result of Montgomery and Vaughan for "sufficiently near" sequences. 相似文献
92.
The aim of this paper is to give decompositions of some weaker forms of continuity using the concepts of classes B 1, B 2, B 3, αA and αC introduced by ourselves. 相似文献
93.
Celik Tarimci Anda? Karamustafa Kutalmi? Güven Mehmet Kabak Akgül Ye?ilada 《Analytical sciences》2003,19(9):1347-1348
The crystal structure of 1-[3-(3,4-dimethoxyphenyl)-2-propenoyl]pyrrolidine (C15H19NO3) (I) has been determined by X-ray analysis. It crystallizes orthorhombic space group Pbca with a = 24.295(3), b = 15.086(3), c = 7.552(3)A, V = 2768(1)A3, Z = 8, Dcalc = 1.254 g/cm3, mu = (Mo K(alpha)) = 0.87 cm(-1). The title compound has analgesic activity of cycloaliphatic amine part. The molecule is deviated from planar configuration. 相似文献
94.
Charge density fluctuation of low frequency in a dusty plasma 总被引:2,自引:0,他引:2
The charge density fluctuation of low frequency in a dusty plasma, which is derived from the longitudinal dielectric permittivity
of the dusty plasma, has been studied by kinetic theory. The results show that theP value, which describes the relative charge density on the dust in the plasma, and the charging frequency of a dust particle
Ω
c
, which describes the ratio of charge changing of the dust particles, determine the character of the charge density fluctuation
of low frequency. For a dusty plasma ofP≪1, when the charging frequency Ω
c
, is much smaller than the dusty plasma frequency ωd, there is a strong charge density fluctuation which is of character of dust acoustic eigenwave. For a dusty plasma ofP≫1, when the frequency Ω
c
, is much larger than ω
d
there are weaker fluctuations with a wide spectrum. The results have been applied to the ionosphere and the range of radius
and density of dust particles is found, where a strong charge density fluctuation of low frequency should exist. 相似文献
95.
The dependence of cross sections on the colour state of the colliding hadrons is investigated within the Low-Nussinov model of two-gluon exchange. The total cross sections for colour-octet hadrons are practically constant as functions of the hadronic radii, while they tend to zero when the radii of the colour-singlet hadrons approach zero. The slope parameter of the differential clastic cross sections for small momentum transfers is rather insensitive to the colour structure of the colliding hadrons. The integrated colour exchange cross section is calculated. 相似文献
96.
97.
G. Baldsiefen H. Hübel W. Korten U. J. van Severen J. A. Cizewski N. H. Medina D. R. Napoli C. Rossi Alvarez G. Lo Bianco S. Signorelli 《Zeitschrift für Physik A Hadrons and Nuclei》1996,355(1):337-338
High-spin states in196Pb have been populated using the reaction170Er(30Si,4n). The previously observed shears bands in this nucleus have been extended and some of their transitions have been reordered. They now form regular bands with band crossings. One of the bands splits into two pathways at high spin. 相似文献
98.
99.
100.
Hans Grabmüller 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1991,42(5):783-805
Rotationally symmetric deformations of a flat annular elastic membrane under a gravitational force are studied, with prescribed radial stresses or horizontal displacements at the edges. The small-finitedeflection theory of Föppl-Hencky as well as a simplified version of Reissner's static first approximation theory of thin shells of revolution are applied which lead to consider a single, second-order, ordinary differential equation for the derivation of the principal stresses in the membrane. Using analytical methods, the range of those boundary data is determined for which the solutions of the differential equation are wrinkle free in the sense that both the radial and the circumferential stress components are nonnegative everywhere. 相似文献