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71.
Paolo De Lucia J. D. Maitland Wright 《Rendiconti del Circolo Matematico di Palermo》1991,40(3):442-452
Dopo aver dato una definizione di parte convessa di un gruppo topologico, si stabilisce una condizione affinchè il condominio
di una misura sia convesso. 相似文献
72.
73.
M. H. Gehlen M. Van der Auweraer F. C. De Schrwer 《Photochemistry and photobiology》1991,54(4):613-618
The luminescence decay of excited probes in micelles in the presence of a Poisson distribution of quenchers is considered under conditions where both probe and quencher within the lifetime of the excited probe may exchange between the micelles. Analytical and numerical results show that the luminescence decay can be expressed by a generalized self convolution product of a multiexponential decay function. 相似文献
74.
文章讨论无界区域上GBBM方程的Cauchy问题,对方程的解进行了先验估计,并证明了在H1弱拓扑中整体吸引子的存在性. 相似文献
75.
76.
Bart De Bruyn 《Journal of Algebraic Combinatorics》2006,24(1):23-29
Brouwer and Wilbrink [3] showed the nonexistence of regular near octagons whose parameters s, t2, t3 and t satisfy s ≥ 2, t2 ≥ 2 and t3 ≠ t2(t2+1). Later an arithmetical error was discovered in the proof. Because of this error, the existence problem was still open
for the near octagons corresponding with certain values of s, t2 and t3. In the present paper, we will also show the nonexistence of these remaining regular near octagons.
MSC2000 05B25, 05E30, 51E12
Postdoctoral Fellow of the Research Foundation - Flanders 相似文献
77.
De Ming ZHU Ying SUN 《数学学报(英文版)》2007,23(8):1495-1504
In this paper, we study the dynamical behavior for a 4-dimensional reversible system near its heteroclinic loop connecting a saddle-focus and a saddle. The existence of infinitely many reversible 1-homoclinic orbits to the saddle and 2-homoclinic orbits to the saddle-focus is shown. And it is also proved that, corresponding to each 1-homoclinic (resp. 2-homoclinic) orbit F, there is a spiral segment such that the associated orbits starting from the segment are all reversible 1-periodic (resp. 2-periodic) and accumulate onto F. Moreover, each 2-homoclinic orbit may be also accumulated by a sequence of reversible 4-homoclinic orbits. 相似文献
78.
S. De Winter 《Advances in Mathematics》2007,214(1):146-156
We solve a long-standing open problem by proving that the automorphism group of any thick Payne derived generalized quadrangle with ambient quadrangle S a thick generalized quadrangle of order s, s?5 and odd, with a center of symmetry, is induced by the automorphism group of S. 相似文献
79.
S. O. Olabanji O. R. Omobuwajo D. Ceccato M. C. Buoso M. De Poli G. Moschini 《Journal of Radioanalytical and Nuclear Chemistry》2006,270(3):515-521
Summary Analysis of thirteen medicinal plants of various biological activities commonly used in South-western Nigeria was carried
out using PIXE technique. Nine of these plants are anti-cancer while four are antimicrobial. PIXE measurements were carried
out using collimated proton beams delivered by the 2. 5 MV AN 2000 Van de Graaff accelerator at the Istituto Nazionale di
Fisica Nucleare (INFN), (LNL) Legnaro, (Padova), Italy. The results showed the presence of twenty three different elements
in the plants and none of them contains any toxic heavy metals. Only Chenopodium ambrosioides showed detectable levels of selenium which is considered important in cancer prevention. 相似文献
80.
Valuations of dense near polygons were introduced in 16 . In the present paper, we classify all valuations of the near hexagons ??1 and ??2, which are related to the respective Witt designs S(5,6,12) and S(5,8,24). Using these classifications, we prove that if a dense near polygon S contains a hex H isomorphic to ??1 or ??2, then H is classical in S. We will use this result to determine all dense near octagons that contain a hex isomorphic to ??1 or ??2. As a by‐product, we obtain a purely geometrical proof for the nonexistence of regular near 2d‐gons, d ≥ 4, whose parameters s, t, ti (0 ≤ i ≤ d) satisfy (s, t2, t3) = (2, 1, 11) or (2, 2, 14). The nonexistence of these regular near polygons can also be shown with the aid of eigenvalue techniques. © 2005 Wiley Periodicals, Inc. J Combin Designs 14: 214–228, 2006 相似文献