基于半导体光放大器的环路型全光缓存器中功率均衡的新方法

全光缓存器能够在光域内对数据包进行存储而不需经过光电光的变换,成为全光网的重要组成部分,其性能的优劣将直接影响到网络的丢包率等。但在半导体光放大器中交叉增益调制和交叉相位调制效应并存,导致基于半导体光放大器的环路型全光缓存器中缓存后输出的数据包与未缓存数据包的输出功率间存在不均衡,使得网络误码率增加。在详细分析全光缓存器工作原理的基础上,利用半导体光放大器中交叉增益调制和交叉相位调制并存的现象,巧妙地提出了将控制脉冲反相并配合电可调衰减器的新方法。该方法简单易行,有效解决了此类全光缓存器中数据包输出功率不均衡的难题,缓存器性能得到了极大改善。此方法适用于所有基于半导体光放大器的环路型全光缓存器。     

On the post-buckling analysis of plastic structures under impulsive loading

An analytical method is suggested to analyze the plastic post-buckling behavior under impulsive loading. The fundamental equation of motion of a cylindrical shell is taken as an example to explain the main concept and procedure. The axial and the radial displacements are decoupled by an approximate scheme, so that only one non-linear equation for the radial buckling displacement is to be solved. By expanding it in terms of an amplitude measure as a time variable, we may get the post-buckling behavior in the form of a series solution. The post-buckling behavior of a rectangular plate used as a special case of cylindrical shell is discussed.     

煤大分子结构的电子自旋共振谱表征

应用ＥＳＲ技术对一变质系列煤的自由基特性进行了实验研究，探讨了煤中自由基的起源、性质和数量的变化，并将其与煤的大分子结构相关联。结果表明，煤自由基特性在煤化过程中的规律性较好。     

Resonance Rayleigh scattering spectrum for the chelate of lanthanum(Ⅲ) with sodium tanshinon ⅡA silate and its analytical application

In a pH 3.6―5.0 HAc-NaAc buffer solution, when sodium tanshinon ⅡA silate (STSⅡA) reacts with La(Ⅲ) to form a chelate, the resonance Rayleigh scattering (RRS) intensity can be en-hanced greatly and a new RRS spectrum will appear. The maximum RRS peak is located at 306 nm and the RRS intensity is proportional to the concentration of STSⅡA in a certain range. The method is very sensitive and the detection limit for STSⅡA (3σ/K) is 82.12 ng·mL?1. The optimum reaction condi-tions and the effect of coexisting substances have been investigated. A new, simple and fast method for the determination of STSⅡA based on RRS method is developed. It can be applied to the deter-mination of STSⅡA in the synthesis samples and Nuoxinkang injection. Combined with infrared ab-sorption and NMR spectra, the structure of the chelate and the reasons of RRS enhancement are also discussed.     

原子外层轨道能级与电子的电离顺序

本文根据光谱实验结果和量子数意义,归纳出一个n、1规则:E=n+1-(1-0.75)/(1+1)。n为主量子数,l为角量子数。计算的E值大小,可用来判别原子外层轨道能级高低顺序,确定原子核外电子的电离顺序,预测新的元素周期等。     

银电极表面氧化物的形成与转变

金属银是碱性电池的重要电极材料,人们已对它在碱性水溶液中的电化学反应进行广泛的研究,但其阳极氧化过程的分析以及氧化产物的鉴定至今仍是众说不一。为此,本文采用现场电化学X-射线衍射技术并配合循环伏安实验进行了研究。现场X-射线衍射实验在一个特制的有机玻璃电解池中进行。整个电解池系统犹如普通粉末样品架一样安放干衍射仪的样品台上,其中透射X-射线的窗片为聚酯薄膜。研究电极是将15×10×2mm~3的银片(纯度为99.99%)用环氧树脂灌封而成,并使用饱和甘汞电极     

Study on Synthesis and Intercalation Behavior of Layered Zirconium Proline-N-methylphosphonate-phosphate

Zirconium proline-N-methylphosphonate-phosphate (α-ZPMPP) was prepared in the presence of HF for the first time. The α-ZPMPP sample is highly crystallized with interlayer distance of 1.52nm. The interlayer distance of complex of α-ZPMPP with n-butylamine (α-ZPMPP-BA) is in 0.45 nm larger than that of α-ZPMPP. The α-ZPMPP possesses different intercalation behavior of host-guest compound from α-ZP.     

Theoretical study of bifurcated bent blue-shifted hydrogen bonds CH_2…Y

Ab initio quantum chemistry methods were applied to study the bifurcated bent hydrogen bonds Y… H2CZ (Z = O, S, Se) and Y…H2CZ2 (Z = F, Cl, Br) (Y = Cl-, Br-) at the MP2/6-311 G(d,p) and MP2/6-311 G(2df,2p) levels. The results show that in each complex there are two equivalent blue-shifted H-bonds Y…H—C, and that the interaction energies and blue shifts are large, the energy of each Y…H—C H-bond is 15-27 kJ/mol, and Δr(CH) = -0.1 - -0.5 pm and Δv(CH) = 30 - 80 cm-1. The natural bond orbital analysis shows that these blue-shifted H-bonds are caused by three factors: large rehybridization; small direct intermolecular hyperconjugation and larger indirect intermolecular hy- perconjugation; large decrease of intramolecular hyperconjugation. The topological analysis of elec- tron density shows that in each complex there are three intermolecular critical points: there is one bond critical point between the acceptor atom Y and each hydrogen, and there is a ring critical point inside the tetragon YHCH, so these interactions are exactly H-bonding.     

高效液相色谱法快速,灵敏测定尿中3—甲基组氨酸含量

本文报道用柱前衍生高液相色谱法快速，灵敏地测定尿中３－甲基组氨酸（３ＭＨ）。采用含３０％乙腈的１０ｍｍｏｌ／Ｌ磷酸钠缓冲液（ｐＨ＝７．５）为流动相，等梯度洗脱，１０ｍｉｎ内即可分析一个样品；在２０－３０００ｐｍｏｌ范围内，３ＭＨ线性相关系数为０．９９８６，相对标准偏差为２．３％（批内）和４．５％（批间）；并测定了１０名正常人尿中的３ＭＨ含量。     

Synthesis and photochemistry of novel bromo substituted stilbene derivatives as triplet state sensitizers for the generation of singlet oxygen

We have presented the synthesis and characterization of three new bromo substituted stilbene derivatives,p-3,4,5-trimethoxy-p'- 2,3,4,5,6-pentabromostilbene(C1),p-N,N-dimethylamino-p'-2,3,4,5,6-pentabromostilbene(C2) and p-N,N-diphenylamino-p'- 2,3,4,5,6-pentabromostilbene(C3) in this letter.The UV/vis absorption and photoluminescence were investigated in various solvents.The maximal absorption wavelength of C1 exhibited blue-shift to those of C2 and C3 in different solvents.No florescence emission could...