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111.
Yoshimi Egawa Mariko Hagita Ken-ichi Kawarabayashi Hong Wang 《Discrete Mathematics》2003,270(1-3):115-125
Let d, k and n be three integers with k3, d4k−1 and n3k. We show that if d(x)+d(y)d for each pair of nonadjacent vertices x and y of a graph G of order n, then G contains k vertex-disjoint cycles converting at least min{d,n} vertices of G. 相似文献
112.
LiAlO2 single crvstals doped with Ti at concentration 0.2at.% are grown by the Czochralskl technique with dimensions φ42×55mm. Ti ions in the crystal are quadrivalence proven by comparing the absorption and fluorescence spectra of pure LiAlO2 and Ti: LiAlO2. After air and Li-rich atmosphere annealing, the absorption peaks in the range of 600-800nm disappear. We conclude that 682 and 756nm absorption peaks are attributed to the VLi and Vo absorptions, respectively: The peaks at 716nm and 798nm may stem from the VLi^+ and absorptions. The colour-centre model can be applied to explain the experimental phenomena. Ti^4+-doping produces more lithium vacancies in the LiAlO2 crystal. The intensities of [LiO4] and the associated bonds remain unchanged, which improves the anti-hydrolyzation and thermal stability of LiAlO2 crystals. 相似文献
113.
Let f be a smooth map between unit spheres of possibly different dimensions. We prove the global existence and convergence of the mean curvature flow of the graph of f under various conditions. A corollary is that any area‐decreasing map between unit spheres (of possibly different dimensions) is isotopic to a constant map. © 2004 Wiley Periodicals, Inc. 相似文献
114.
Matrix extensions and eigenvalue completions, the generic case 总被引:2,自引:0,他引:2
William Helton Joachim Rosenthal Xiaochang Wang 《Transactions of the American Mathematical Society》1997,349(8):3401-3408
In this paper we provide new necessary and sufficient conditions for the so-called eigenvalue completion problem.
115.
In this article we have studied the nonlinear interaction between ellipticity and dissipation in a set of model equations (1.1) and established the relation between this interaction and chaos. In addition to theoretical investigations, extensive numerical simulations with these equations have been made, and different routes to chaos have been found. The numerical studies have revealed the chaotic nature of the solutions. 相似文献
116.
探讨了设计负动量压缩因子(αp<0)的正负电子对撞机储存环磁聚焦结构的可行性及方法.作为应用实例,说明了设计αp<0的τ–粲工厂磁聚焦结构的可能性. 相似文献
117.
Three hen egg-white lysozyme inhibitor producing strains, Enterobacter cloacae M-1002, E. sakazakii M-1204, and Erwinia rhapontici H-55, were isolated from the soils of Taiwan. E. cloacae M-1002 appeared to be a promising inhibitor producing strain. One inhibitor was isolated from the culture broth of this strain. Maximum lysozyme inhibitory activity was obtained when the bacterium was grown aerobically in a medium consisting of 0.75% glucose, 0.25% beef extract, 1.0% polypeptone, and 0.25% sodium L-glutamate (pH 70) at 37 °C after 36–48 hrs. A hen egg-white lysozyme inhibitor was isolated from the culture broth of this strain. The inhibitor was purified from the culture supernatant of E. cloacae M-1002 by ammonium sulfate fractionation, DEAE-Sepharose CL-6B column chromatography and Fractogel TSK HW-55 (S) gel chromatography. Molecular weight of the purified lysozyme inhibitor was estimated to be 18, 000–20, 000 by SDS-PAGE and HPLC, and was composed of 71% amino acid and 23% total sugar. Serine, glycine, and alanine in a 3:2:1 molar ratio were the major amino acids, calculated to be 32.8, 20.3, and 11.4% (mol%), respectively. Glucose and mannose were the major sugar components of the inhibitor. The inhibitor was stable at pH 5 to 8 and was stable under 50 °C. Only hen egg-white lysozyme was inhibited by the purified inhibitor but not the other tested enzymes such as lysozyme of celery, turnip; lytic enzyme of Pseudomonas aeruginosa M-1001; chitinase/lysozyme of P. aeruginosa K-187; or cellulase and xylanase of Streptomyces actuosus A-151 and Aspergillus sp. G-393. The inhibition of lysozyme to the bacterial cell lytic activity by the purified inhibitor was 100%. 相似文献
118.
Two Convergence Problems for Monotone Sequences 总被引:1,自引:0,他引:1
Eight measures of rate of convergence of monotone sequences of real numbers have been proposed and discussed in a paper by Beyer, Ebanks, and Qualls (Acta Appl. Math. 20 (1990), 267–284). These rates arose in discussions of dynamical systems. In the comparisons of these rates, two problems remained. A complete answer is given to one of the problems and a partial answer is given to the other problem. 相似文献
119.
120.