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InGaAs(P)分别限制应变单量子阱激光器的优化设计   总被引:1,自引:0,他引:1  
针对较常用的InGaAs(P)分别限制应变单量子阱激光器,给出了为得到最大净增益的优化设计参数。对于激射波长为1.55μm的无应变激光器,最佳的光限制层波长为1.24μm,厚度为100nm。当阱材料引入压缩应变后.由于价带的有效状态密度减小,量子阱激光器的微分增益变大,阱深的增大对增大线性增益的效果更加明显.所以最佳光限制层的波长将变短,为1.20μm  相似文献   
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The cardioprotective effects of EGb 761 on the release of nitric oxide (NO), the concentration of serum thiobarbituric acid reaction substance (TBARS), the activity of creatine kinase (CK) and the incidence of ventricular arrhythmias were investigated in myocardial ischemia-reperfusion injury in vivo. Using sodium nitrite (NaNO2) as standard source of nitric oxide (NO), we compared the correlation coefficients of the three measuring methods used currently in the determination of NOFe2+(DETC)2 complex with that of the measuring method suggested in this study. The result showed that measuring the whole height of three splitting signals is the best linear correlation to the concentration of NO comparing with other methods in this system. Using this method, we observed the effects of EGb 761 on NOFe2+(DETC)2 complex in myocardial ischemia-reperfusion injury in vivo. The hearts of the Wistar rats were subjected to 30 min of ischemia and 10 min of reperfusion in vivo. Different doses of EGb 761 (25, 50, 100, 200 mg/kg i.p.), superoxide dismutase (SOD, 10(4) U/kg), l-arginine (50 mg/kg i.p.) and nitric oxide synthase (NOS) inhibitor NG-nitro-l-arginine (NNA, 50 mg/kg i.p.) were administered to the ischemia-reperfusion rats. EGb 761 under the dose of 100 mg/kg increased the signal intensity of NOFe2+(DETC)2 complex, while EGb 761 at 200 mg/kg showed an effect of decreasing the signal intensity of NOFe2+(DETC)2 complex. EGb 761 inhibited the formation of TBARS, the release of CK, and mitigated the incidence of ventricular arrhythmias in a dose dependent way. Both l-arginine and SOD increased the signal intensity of NOFe2+(DETC)2 complex and inhibited the formation of TBARS, the leakage of CK and the incidence of ventricular arrhythmia. NNA not only had no protective effects on myocardial injury, but also increased the incidence of reperfusion-induced arrhythmia. In conclusion, EGb 761 has cardiovascular protective effects by means of adjusting the level of NO and inhibiting oxygen free radicals induced lipid peroxidation in myocardial ischemia-reperfusion injury in vivo.  相似文献   
76.
在30CrMnSiA钢中加入不同量的As,Sb,Sn元素,研究了这些元素单独存在及复合存在时对钢的强度,塑性,冲击韧度及韧脆转变温度的影响规律,并用扫描电镜及俄歇能谱分析了As,Sb,Sn导致晶界脆化的机理。  相似文献   
77.
国外阳离子SBR胶乳的生产及应用   总被引:1,自引:0,他引:1  
  相似文献   
78.
将气体动压轴压简化为转化气膜系统后,针对其动力特点,给出气膜在微幅振动下动压轴承的实用数学模型和测定动态参数的方法,并进行了测量误差的修正。  相似文献   
79.
探讨在PB开发的应用程序中利用数据窗口列对象的Tag属性,结合自行设计的一个更改SELECT语句中的Where子句的全局函数,实现应用程序多表数据的动态查询。该种方法是PB开发的应用程序中实现数据查询的一种高效、简洁且行之有效的方法。  相似文献   
80.
Summary Byzantine Agreement is important both in the theory and practice of distributed computing. However, protocols to reach Byzantine Agreement are usually expensive both in the time required as well as in the number of messages exchanged. In this paper, we present a self-adjusting approach to the problem. The Mostly Byzantine Agreement is proposed as a more restrictive agreement problem that requires that in the consecutive attempts to reach agreement, the number of disagreements (i.e., failures to reach Byzantine Agreement) is finite. Fort faulty processes, we give an algorithm that has at mostt disagreements for 4t or more processes. Another algorithm is given forn3t+1 processes with the number of disagreements belowt 2/2. Both algorithms useO(n 3) message bits for binary value agreement. Yi Zhao is currently working on his Ph.D. degree in Computer Science at University of Houston. His research interests include fault tolerance, distributed computing, parallel computation and neural networks. He obtained his M.S. from University of Houston in 1988 and B.S. from Beijing University of Aeronautics and Astronautics in 1984, both in computer science. Farokh B. Bastani received the B. Tech. degree in electrical engineering from the Indian Institute of Technology, Bombay, India, and the M.S. and Ph.D. degrees in electrical engineering and computer science from the University of California, Berkeley. He joined the University of Houston in 1980, where he is currently an Associate Professor of Computer Science. His research interests include software design and validation techniques, distributed systems, and fault-tolerant systems. He is a member of the ACM and the IEEE and is on the editorial board of theIEEE Transactions on Software Engineering.  相似文献   
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