偏振模色散对多信道光纤通信系统信号的影响

利用耦合非线性薛定谔方程,计算了考虑PMD和非线性效应情况下8×40 Gb/s波分复用光纤通信系统中的波形及频谱.与不考虑PMD结果的比较表明:由于PMD的影响使得波形变宽,频谱分裂,同时通过比较还发现PMD对各信道的影响是不同的,这将有利于开发WDM系统中PMD补偿系统.     

Nonlinearity of InP-Doped Fibers

By combining nano-technology with fiber technology, an optical fiber doped with semiconductor nano-particles as InP is fabricated by using the modified chemical vapor deposition （MCVD） method. Proved by experiment, the fiber has excellent waveguide characteristics, and the concentration of InP is approximately 0.1~o. By using a scanning electron microscope, a stereo-scan photograph of the fiber is obtained, and based on the graph, presentations of the fiber under both magnetic and electronic fields are simulated, the effective core area Aeff≈ 10μm^2 is calculated, and so is the nonlinear index γ = 10.53 W^-1/Km of the fiber. This research leads a new method of high nonlinearity fiber fabrication.     

电偶腐蚀引起的30CrMnSiA钢力学性能的退化

研究了TC4钛合金与30CrMnSiA合金钢耦接后,其电偶腐蚀对电偶对中阳极30CrMnSiA合金钢力学性能的影响。结果发现:随着时间的延长,30CrMnSiA合金钢因电偶腐蚀引起合金钢厚度减薄量不断增加,使得30CrMnSiA合金钢的力学性能因合金钢有效承载尺寸减小而降低;与拉伸载荷变化趋势相比,由于腐蚀作用,30CrMnSiA合金钢的表面硬度降低更为明显。     

超短曝光时间下激光散斑对比度速度分析

采用0.205ms的曝光时间,研究了观测速度范围包含去相关区域和未去相关区域时的散斑对比度与观测物速度间的关系。结果表明,利用对比度随取样帧数的变化趋势,并结合时间序列散斑图像相关系数曲线,可以在复杂环境下正确区分两个区间内的速度大小;同时,选用适当散斑图像帧数进行对比度计算,可以同时为探测大速度和小速度区间的速度变化提供较高灵敏度。     

Suppercontinuum Generation in InP Nano Inner Cladding Fibers

The InP nano inner cladding fiber is fabricated by the method of modified chemical vapor deposition. The thickness of the InP nano thin film is about 16 nm. A 20 dB supercontinuum over 100nm in the telecommunication band is generated by infecting 1550nm, 120fs, 50MHz repetition rate optical pulse into this kind of fiber. Moreover, the results indicate that the width of the supercontinuum spectra can be influenced by the fiber length and pump power. The longer fiber at higher pump power can produce broader supercontinuum spectrum.     

钽激光等离子体的自电离和辐射衰减特性(英文)

在自旋轨道劈裂阵模型下,考虑组态间的耦合,计算出类铜钽激光等离子体的跃迁组态的波长和对应的波数,通过组态平均分析了其自电离与辐射跃迁特性,得出相关的自电离系数和辐射衰减系数,这些参数为分析高离化钽激光等离子体的双电子复合过程提供了重要的理论依据.     

(Ni0.8Zn0.2Fe2O4)epoxy-PZT双层膜中的磁电效应

讨论了Ni0.8Zn0.2Fe2O4(NZFO)与锆钛酸铅(PZT)的双层膜结构样品的磁电(ME)效应.NZFO粉料由溶胶-凝胶法制成,再经900℃热压,并高温烧结.在该双层膜中测量到了很强的磁电相互作用.发现横向的磁电效应比纵向效应大一个数量级,并且随NZFO烧结温度的提高而增加.当烧结温度从950℃上升到1380℃时,横向ME电压系数(αE)的最大值变化范围为25.6 mV Am-2≤αE≤199.6 mV Am-2.理论分析显示NZFO-PZT双层膜样品中ME效应源于NZFO与PZT之间相对良好的磁电耦合.     

Quantum Secure Direct Communication with Authentication Expansion Using Single Photons

In this paper we propose two quantum secure direct communication （QSDC） protocols with authentication. The authentication key expansion method is introduced to improve the life of the keys with security. In the first scheme, the third party, called Trent is introduced to authenticate the users that participate in the communication. He sends the polarized photons in blocks to authenticate communication parties Alice and Bob using the authentication keys. In the communication process, polarized single photons are used to serve as the carriers, which transmit the secret messages directly. The second QSDC process with authentication between two parties is also discussed.     

非扩散性三光束冷原子吸收法直接测定大米中的汞

基于热解-催化还原-冷原子吸收法原理,采用直接进样测汞法测定大米中的汞含量。稻米样品经脱壳、粉碎、研磨后过孔径为0.425 mm的筛,称取一定质量的样品置于样品舟内,样品经干燥、分解、催化、汞齐化富集,生成的汞蒸汽由氧气导入冷原子吸收器,在波长253.7 nm处检测,用标准曲线法定量。汞的质量在0～200.0 ng的范围内与吸光度峰面积线性关系良好,相关系数为0.999 9,检出限为0.014 8μg/kg。样品加标回收率为92.6%～101.8%,大米样品和大米粉中汞成分分析标准物质测定结果的相对标准偏差分别为2.8、2.4(n=6)。该方法简单、快捷,无需样品前处理过程,可作为大米中汞的检测方法。