公司大门工程建设施工

大门小品建筑属多项目综合性工程。本文作者从管理者的角度 ,通过对公司大门及附属工程施工质量控制的总结 ,说明了质量控制应贯穿于工程施工的全过程     

Design of Polarization-independent Wavelength-interleave Coupler in Fluorinated Polyimide Waveguide

Based on the measurement of dispersion characteristic and birefractive index of the fluorinated polyimide film,a statistical optimum design method is proposed and used to realize the design of 32-and 36-wavelengths optical waveguide wavelength-interleave coupler (i,e.,interleaver) with the optimization of polarization fluctuation and wavelength interval of 0.8nm at 1550nm. The largest cross coupling ratios of the two interleavers are respectively less than 1.8% and 3.5%, while the least through coupling ratios are respectively greater than 98. 2% and 96. 5%. The output differences due to polarization fluctuation are less than 1.7% and 3.2%     

通信瓶颈下的实时并行任务分配研究

提出了实时并行任务粒度划分的具体设计方法，采用了系统内通信迟延最小的约束条件进行多处理器上的任务分配，解决了高速实时信号处理中的数据通信瓶颈问题。在自行设计的超立方体结构的通用信号处理机上，实现了空时二维自适应信号处理和SAR实时成像，显著减小了数据通信迟延，提高了并行效率和性价比。     

Photoluminescence and X-ray Diffraction of Distributed Bragg Reflector

Spectral and structural characteristics of distributed Bragg reflector (DBR) in vertical-cavity surface-emitting lasers were studied with photoluminescence and double- crystal X- ray diffraction measurement. The expected high quality epitaxial DBR structure was verified. In the X- ray double- crystal rocking curves of DBR the zeroth- order peak, the first and second order satellite peaks were measured. Splitting of diffraction peak appeared in the rocking curves was analyzed. The effects of introduced deep energy levels on the structural perfection and optical properties were discussed.     

Experimental Research on Erbium-doped Superfluorescent Fiber Source

The effects of the variations in fiber length, fiber mirror reflectance on efficiency and output power are experimentally investigated for erbium-doped double pass backward superfluorescent fiber sources (SFSs). The influence of fiber length on mean wavelength stability (MWS) has also been demonstrated. By incorporating a short section of un-pumped erbium-doped fiber (EDF) at the output port, the pump power dependent on MWS becomes independent of pumped EDF length. This is a novel phenomenon that hasn‘t been reported up to now,and should be helpful to SFS fabrication and theory analysis. By using a fiber Michelson interferometer as spectrum slicing component,a multi-wavelength fiber source (MWFS) with ～20 channels (from 1542nm to 1559nm) is got. The MWFS has a channel spacing of ～0. 8 nm which satisfies ITUstandard. The intensity fluctuation among channels is less than 0.5dB,and the extinction ratio of all channels is above 14dB. This kind of MWFS should be useful to wavelength division multiplexing systems.     

一种动态开关电容运算放大器共模负反馈电路

本文主要介绍了一种应用于Cascode结构运放中的开关电容共模负反馈电路，它具有稳定性好、对运放频率特性影响小、不消耗额外功率等优点。对电路运用Hspice进行了模拟，并给出了模拟结果。     

Two‐phase production of cyclohexene and cyclooctene oxides in water as an approach to pollution prevention

Liquid–liquid two‐phase epoxidation from cyclohexene and cyclooctene in aqueous potassium peroxymonosulfate (commercially available as Oxone^®) solution was studied as an application in pollution prevention. To avoid potential emissions of volatile organic compounds an aqueous solution was employed to replace the usual chlorinated solvents used in epoxide production. A droplet column reactor and stirred tank reactor were used to investigate two‐phase synthesis of epoxide. An aqueous Oxone^® solution was used to oxidize a dispersion of alkene droplets and form epoxide. The study of aqueous epoxidation in both reactors showed that the epoxidation of alkenes can be represented as a first order reaction with respect to alkene. The salting out effect of Oxone^® concentration was studied in both reactors and found to be very similar at optimal conditions. In comparing the two reactors, it was found that the droplet column reactor produces larger quantities of product per unit reactor volume for the same reaction time. The objective of this study is to provide an alternative reactor design and synthesis route that can meet pollution prevention goals. Copyright © 2004 Society of Chemical Industry     

基于因特网的远程校准技术进展

远程校准是信息技术特别是计算机网络技术与传统的计量测试技术结合的必然产物。本文介绍与之有关的一些概念及国外开展相应项目的情况。结合我们自己的一个实验装置．对在我国开展远程校准工作的必要性和可行性提出一些看法。     

Ca^2＋、Sr^2＋掺杂对Pr0.6CaxSr0.4-xFeO3-δ物相、结构及电性能的影响

采用柠檬酸-硝酸盐法合成了碱土金属双掺杂的Pr0.6CaxSr0.4-xFeO3-δ（X=0.0-0.4）系列复合氧化物粉体,用TG-DTA，XRD，FT-IR，SEM等手段对产物中钙钛矿物相的形成及微结构进行了表征,结果表明，样品在800℃焙烧2h后显现钙钛矿结构的主要衍射峰；随热处理温度的升高，XRD谱峰强度逐渐增大，1000℃煅烧2h即得到正交钙钛矿结构的单相固溶体；系列样品结晶化程度和晶粒尺寸随样品中Ca含量的增大而减小；电导率测试结果表明，Ca^2＋、Sr^2＋双掺杂样品的电导率随Sr^2＋含量的增大而增大，低温段（T≤650℃）烧结陶瓷体的导电行为遵循小极化子导电机制。     

端电压比较法直接寻找无刷直流电动机换相点及其斩波调速

提供了一种利用端电压比较结合软件算法直接寻找直流无刷无位置传感器电动机换相点的方案，解决了直流无刷无位置传感器电动机控制的关键问题－转子位置检测，并以单片机PIC16C72为核心构成先进的数字控制系统，实现了软件斩波调速。