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This paper deals mainly with the existence and asymptotic behavior of traveling waves in a SIRH model with spatio-temporal delay and nonlocal dispersal based on Schauder ’s fixed-point theorem and analysis techniques,which generalize the results of nonlocal SIRH models without relapse and delay.In particular,the difficulty of obtaining the asymptotic behavior of traveling waves for the appearance of spatio-temporal delay is overcome by the use of integral techniques and analysis techniques.Final... 相似文献
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该文研究了一类具有非局部效应和非线性发生率的时滞SEIR系统的周期行波解.首先,定义基本再生数R0并构造适当的上下解,将周期行波解的存在性转化为闭凸集上非单调算子的不动点问题,利用Schauder不动点定理结合极限理论建立该系统周期行波解的存在性.其次,利用反证法结合比较原理,建立当基本再生数R0<1时该系统周期行波解的不存在性. 相似文献
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RuCl3·3H2O分别与6,6’-二甲基-2,2’-联吡啶(dmbp)和2,2’-联吡啶-6,6’-二甲醛(bpda)反应生成[cisRu(L)2Cl2]Cl·2H2O(L=dmbp,bpda),进一步用CF3SO3Ag脱氯得到[cis-Ru(L)2(H2O)2](CF3SO3)3.研究了4种配合物对1-己炔、苯乙炔和丙炔酸乙酯的催化环三聚作用,发现脱氯后的含水配合物催化活性有显著提高;体系中有水存在时,丙炔酸乙酯环三聚具有很强的区域选择性.催化机理研究表明,该催化过程为催化[2+2+2]环加成反应.钌杂环庚三烯或7-钌杂双环[2.2.1]-2,5-庚二烯是关键中间体,联吡啶配体上的6-甲酰基取代基水合后通过与丙炔酸乙酯的羰基形成分子内氢键影响环三聚产物的区域选择性. 相似文献
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The nanostructures during the tensile drawing of poly(ethylene terephthalate)(PET)/hexadecyl triphenyl phosphonium bromide montmorillonite(PMMT) nanocomposites were studied by in-situ small angle x-ray scattering. For strain higher than the yield point, the scattering intensity increases dramatically due to the nucleation and growth of nanovoids and crystals. The nanovoids and crystals are significantly dependent on the heating temperature. The effective filling of PMMT in the PET matrix provokes a strong restriction to the long period. The peaks of the long period disappear gradually with the deformation strain increasing from 0% to 34%. 相似文献
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