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本文用凸函数的方法研究了概率测度的矩母函数和由C.J.Stone提出的拟对称性,并刻画了Martin边界的法向量.拟对称性在随机游动的比例极限定理中是一个重要的概念.这些结果可应用于Levy过程的研究. 相似文献
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徐宪民 《数学年刊A辑(中文版)》2003,(3)
Riemann曲面M上的平方可测1-形式全体和解析1-形式全体均可构成Hilbert空间。本文讨论Riemann曲面上的解析映射导出的这类Hilbert空间上的复合算子,研究复合算子的正常性、拟正常性的诱导映射特征。特别地,当M有有限三角剖分时,证明了正常复合算子、拟正常复合算子、酉复合算子、等距复合算子和可逆复合算子等价。 相似文献
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Let ∑, Г be two n-by-n diagonal matrices with σi,γi as their diagonals. For the inverse eigenvalue problem: look for y∈Rn such that Г + yyT is similar to ∑, we prove thatu also the sufficient condition for the solvability of this inverse problem. Its solution (set) is given explicitly. In some case, the problem is unstable. But we prove that the sums of the square of some contigious components keep stable, i.e., small sum keeps small, large sum has a small relative perturbation, see Theorem 3. 相似文献
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聚合条件对N-羧基-L-丙氨酸-环内酸酐开环聚合产物分子量的影响 总被引:3,自引:0,他引:3
用光气法制备了N-羧基-L-丙氨酸-环内酸酐(L-Alanine NCA).系统研究了L-Alanine NCA开环聚合反应过程中引发剂、溶剂、温度对聚合物分子量的影响.用硝基苯作溶剂,三乙胺作引发剂,所得聚合物特性粘度[η]=1.18.实验中发现,L-Alanine NCA可以顺利地进行热聚合反应。反应具有速率快,转化率高,分子量大的特点。甲苯溶剂中反应5小时所得聚合物[η]=2.35,高于采用引发剂的聚合体系产物的相应值。 相似文献
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IntroductionAlPO 2 1isatypeofmicroporousaluminophosphatepreparedbyFlanigenandco workersin 1982 ,andthestructurewasresolvedbySmithetal.1in 1984 .AlmostatthesametimePariseetal.2 preparedAlPO 2 1phasebyanotherrouteandresolvedthestructureindependently .Inthenextyear ,GaPO 2 1phasewasobtainedaswell.3Al thoughAl(Ga)PO 2 1phasespreparedindifferentwayspossesssimilarchannelsystem ,amongthemtherearestillsomedifferencesinlatticeconstants ,indicatingthatdiffer enttemplatemoleculescanaffectlocallythe… 相似文献
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LAI NingAn & ZHOU Yi School of Mathematical Sciences Fudan University Shanghai China 《中国科学 数学(英文版)》2011,(2):205-220
In this paper, we consider the exterior problem of the critical semilinear wave equation in three space dimensions with variable coefficients and prove the global existence of smooth solutions. As in the constant coefficients case, we show that the energy cannot concentrate at any point (t, x) ∈ (0, ∞) ×Ω. For that purpose, following Ibrahim and Majdoub's paper in 2003, we use a geometric multiplier similar to the well-known Morawetz multiplier used in the constant coefficients case. We then use the compari... 相似文献
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对带有控制-状态混合约束的一类受控时滞Volterra型积分系统,导出了其最优控制的一组必要条件和一组充分条件. 相似文献
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CHEN Meng School of Mathematical Sciences & LMNS Fudan University Shanghai China 《中国科学 数学(英文版)》2011,(8)
We investigate birationality of the anti-pluricanonical map Φ-m,the rational map defined by the anti-pluricanonical system |-mKX|,on weak Q-Fano 3-folds. 相似文献
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本文研究了单位圆周上一类具有本质边界点的拟对称同胚,证明了它的极值拟共形延拓的最大伸缩商等于曲边四边形模之比的上确界. 相似文献