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981.
In this paper, an optimal routing strategy is proposed to enhance the traffic capacity of complex networks. In order to avoid nodes overloading, the new algorithm is derived on the basis of generalized betweenness centrality which gives an estimate of traffic handled by the node for a route set. Since the nodes with large betweenness centrality are more susceptible to traffic congestion, the traffic can be improved, as our strategy, by redistributing traffic load from nodes with large betweenness centrality to nodes with small betweenness centrality in the proceeding of computing collective routing table. Particularly, depending on a parameter that controls the optimization scale, the new routing can not only enlarge traffic capacity of networks more, but also enhance traffic efficiency with smaller average path length. Comparing results of previous routing strategies, it is shown that the present improved routing performs more effectively. 相似文献
982.
针对植物航天育种变异大的特点,利用傅里叶变换红外光谱(FTIR)结合二阶导数谱对第4代航天育种白芷与地面组白芷从整体上对主要组分进行测定和对比分析。结果表明:太空白芷主要活性成分香豆素类组分(1 741cm-1)含量增加,蛋白质(1 459,1 419cm-1)和脂肪(930cm-1)组分含量略有增加;而淀粉、膳食纤维(1 152,1 105,1 080,1 050cm-1)的含量大幅度降低。二阶导数谱中峰强差异更明显,1 279cm-1处揭示出太空白芷含有胺类组分。航天育种有利于选育出变异幅度大的特异质白芷新品种。 相似文献
983.
984.
以双甘氨肽(Gly-Gly)为印迹分子,丙烯酰胺(AM)、二甲基丙烯酸乙二醇酯(EDMA)分别作为功能单体和交联剂,在低温条件下采用乳液聚合于水相中制备了双甘氨肽分子印迹聚合物微球(Gly-Gly-MIPMs)。通过静态、动态平衡吸附和薄层色谱(TLC)分离实验,研究了Gly-Gly-MIPMs的选择吸附性能,并进行了Scatchard模型分析。结果表明,Gly-Gly-MIPMs对Gly-Gly分子具有较好的特异性吸附,最大单位饱和吸附量0.428mmol/g,印迹因子2.19。 相似文献
985.
含二氯丙烯的亚硫酸酯类化合物的合成及杀虫活性测定 总被引:1,自引:0,他引:1
为了寻找和发现高效、广谱、低毒、低生态风险并与现有杀虫剂无交互抗性的新型杀虫剂,以对苯二酚为原料,经多步反应制得11个新型含二氯丙烯的亚硫酸酯类化合物,其结构经核磁共振氢谱、碳谱、元素分析确证.室内生物活性测定结果表明,目标化合物对小菜蛾(Plutella xylostella L.)具有较好的杀虫活性,其中3-[2,6-二氯-4-(3,3-二氯烯丙氧基)苯氧基]丙基正己基亚硫酸酯(7h)在10 mg/L下对小菜蛾的致死率可达到80%,优于对照药三氟甲吡醚. 相似文献
986.
Atractylenolide II (AII) and atractylenolide III (AIII) are the major active components in Atractylodes Macrocephala Rhizoma (AMR). In this study, a sensitive, rapid and selective liquid chromatography–tandem mass spectrometry (LC‐MS/MS) method was developed and validated for the simultaneous determination of AII and AIII in rat plasma using loliolide as internal standard (IS). After protein precipitation with ethyl acetate, the analytes were injected into an LC‐MS/MS system for quantification. Chromatography was performed using a C18 column, eluting with water and acetonitrile (45:55, v/v) at 0.2 mL/min. All analytes including IS were monitored under positive ionization conditions by multiple reaction monitoring with an electrospray ionization source. The validated method was successfully applied to the pharmacokinetic study of AII and AIII in rat plasma after oral administration of AMR extract. The results provided a meaningful basis for evaluating the clinical applications of traditional Chinese medicine. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
987.
以修正后的Rapini-Papoular锚定能公式为基础, 用理论分析和数值计算相结合的方法, 详细研究表面极化对液晶盒饱和特性的影响. 得出了求解指向矢分布的数学方程, 推导出了计算正常二级转变饱和电压的解析式, 同时结合最新报道, 给出了异常一级转变饱和电压的数值计算方法. 此外, 本文引入了反映指向矢分布特征的参量, 讨论了表面极化对此参量的影响. 结果表明, 指向矢最大倾角的位置随表面极化的增大将远离中央平面向基板移动. 一级转变饱和电压随弱锚定基板表面极化的增大而减小, 随强锚定基板表面极化的增大而增大. 而对二级转变, 饱和电压随表面极化的变化与一级转变恰恰相反. 本文所得结论对液晶表面物理的理解及液晶实际应用都具有重要的指导意义. 相似文献
988.
This paper investigates the chaotification problem of complex dynamical networks (CDN) with impulsive control. Both the discrete and continuous cases are studied. The method is presented to drive all states of every node in CDN to chaos. The proposed impulsive control strategy is effective for both the originally stable and unstable CDN. The upper bound of the impulse intervals for originally stable networks is derived. Finally, the effectiveness of the theoretical results is verified by numerical examples. 相似文献
989.
Geometric phases in qubit-oscillator system beyond conventional rotating-wave approximation
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In this work we investigated the geometric phases of a qubit-oscillator system beyond the conventional rotating- wave approximation. We find that in the limiting of weak coupling the results coincide with that obtained under rotating-wave approximation while there exists an increasing difference with the increase of coupling constant. It was shown that the geometric phase is symmetric with respect to the sign of the detuning of the quantized field from the one-photon resonance under the conventional rotating-wave approximation while a red-blue detuning asymmetry occurs beyond the conventional rotating-wave approximation. 相似文献
990.
Transmission characteristics of one-dimensional (1D) photonic crystals (PCs) heterostructures containing defective are studied using the transfer matrix method. The key is to search the best combination style for different 1D PCs to form heterostructures. It is shown that the non-transmission range over near ultraviolet and visible range can be substantially enlarged and the phenomenon of narrow band PC filter in near ultraviolet can be realized by adjusting the repeat cycle counts of various photonic crystals. The theoretical results on multiple heterostructures containing TiO2/SiO2 multilayer films are presented. With a perfect omni-directional and high peak transmission filters for TE modes, this structure opens a promising way to fabricate ultra-narrow band PC filters with wide non-transmission range in near ultraviolet and visible range. 相似文献