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波分复用全光通信网中的放大自发辐射噪声积累效应研究 总被引:3,自引:0,他引:3
给出了一种全光通信网波长域计算机模拟方法,模拟了波分复用信号经过3个光分插复用节点后的信号及放大自发辐射积累的光谱图,并与实验结果进行了对比。计算了波分复用信号经过50个光分插复用节点极限情况下的信噪比,结果表明放大自发辐射噪声积累造成的信噪比下降仍然可以保证接收机在10Gb/s时的误码率小于10^-9。这些结果可以被应用到未来国家或地区级全光通信网中。 相似文献
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以线性耦合波方程为基础,分析了具有不同耦合强度的平面型三光纤耦合系统的模场特性和功率耦合特性,并与常规的平面型三光纤耦合系统的耦合特性作了比较,给出的耦合器谱响应实验结果与理论结果较为一致。 相似文献
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Cyclic voltammetric investigation of the interaction of methylene blue (MB) with heparin (hep) at a gold electrode is presented. The combination of MB with heparin formed a nonelectroactive complex MB-hep, which resulted in the peak current decrease of MB. The anodic peak current difference of MB was found to be proportional to the concentration of heparin in the range of 0.666-64.5 μg mL−1 with a detection limit of 270 ng mL−1 and a satisfactory result was obtained for the determination of heparin in injection samples. The equilibrium constant for MB-hep complex was calculated to be 7.32 × 105. The dynamic process of competition of Ba2+ with methylene blue for binding heparin was monitored using quartz crystal microbalance (QCM) technique. The reaction rate constant between Ba2+ and MB-hep was estimated to be 0.0022 s−1. 相似文献
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1 Introduction Wavelengthroutedopticalnetworkingcanachievetransmissions,routing,switching,andprotectionsofhighspeedinformation... 相似文献
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Ming MaDingsheng He Shenghua LiaoYue Zeng Qingji XieShouzhuo Yao 《Analytica chimica acta》2002,456(1):157-165
A kinetic study of l-isoleucine transport through a liquid membrane containing di(2-ethylhexyl) phosphoric acid (D2EHPA) in kerosene is presented. The influences of pH in the aqueous feed solution, D2EHPA concentration in the organic phase, the stripping solution composition and H2SO4 concentration in the stripping solution were investigated, and the effects of stirring speed and temperature on the transport of l-isoleucine through a bulk liquid membrane (BLM) were studied. The kinetics of l-isoleucine transport could be analyzed in the formalism of a reversible pseudo-first-order reaction followed by an irreversible pseudo-first-order reaction. The pseudo-first-order apparent rate constants of the interfacial transport of l-isoleucine species are determined for the liquid membrane, at various temperatures. The apparent activation energy values are 21.3±1.9, 57.6±5.1 and 31.8±2.7 kJ mol−1 for the extraction reaction, extraction back reaction and stripping reaction, respectively. 相似文献
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Yanlong Wang Jie Deng Chao Zhang Wenfeng Wu Qingji Xie Yachun Liu Zaihui Fu 《Journal of the Iranian Chemical Society》2014,11(6):1723-1729
This paper describes an electrochemical coupling epoxidation of cyclohexene by molecular oxygen (O2) under mild reaction conditions. Herein, the electroreduction of O2 to hydrogen peroxide (H2O2) efficiently proceeds in a relatively environmentally friendly acetone/water medium containing electrolytes at 25–30 °C on a self-assembled H type of electrolysis cell with tree electrodes system, providing ca. 44.3 mM concentration of H2O2 under the optimal electrolysis conditions. The epoxidation of cyclohexene with in situ generated H2O2 simultaneously occurs upon catalysis by metal complexes, giving ca. 19.8 % of cyclohexene conversion with 78 % of epoxidative selectivity over the best catalyst 5-Cl-7-I-8-quinolinolato manganese(III) complex (Q3MnIII (e)). The present electrochemical coupling epoxidation result is nearly equivalent to the epoxidation of cyclohexene with adscititious H2O2 catalyzed by the Q3MnIII (e). 相似文献
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