乌鲁木齐地区多层钢结构住宅经济分析

乌鲁木齐地区建造多层钢结构住宅与传统结构相比所具有的良好经济效益,结合工程实例将钢结构与钢筋混凝土结构进行经济比较,分析表明,钢结构住宅在综合经济性上优于混凝土结构住宅。     

An Ideal Transformer UPFC Model, OPF First-Order Sensitivities, and Application to Screening for Optimal UPFC Locations

This paper presents a screening technique for greatly reducing the computation involved in determining the optimal location of a unified power flow controller (UPFC) in a power system. The first-order sensitivities of the generation cost with respect to UPFC control parameters are derived. This technique requires running only one optimal power flow (OPF) to obtain UPFC sensitivities for all possible transmission lines. To implement a sensitivity-based screening technique for guidance in optimally locating a single UPFC in a power system, we propose a new UPFC model, which consists of an ideal transformer with a complex turns ratio and a variable shunt admittance. In this model, the UPFC control variables do not depend explicitly on UPFC input and output currents and voltages. Accordingly, this model does not require adding extra buses for UPFC input and output terminals. IEEE five-, 14- and 30-bus systems were used to illustrate the technique     

浅谈化学水处理设备衬胶损坏的修补

橡胶衬里被广泛用于火电厂除盐水及凝结水精处理装置中，但是随着设备使用时间的延长会出现，诸如橡胶衬里与金属脱离，橡胶与橡胶之间脱层，胶面起鼓泡、龟裂、针孔、等缺陷，对这些缺陷必须及时进行修补，否则将影响设备的使用寿命及水质。文章介绍了交换器橡胶衬里的常见损坏及修补办法。     

5CrMnMo锻模使用中的失效分析与防止措施

介绍了5CrMnMo钢的化学成分、热处理工艺、锻模的工作条件及其失效形式(型腔棱边磨损、型腔塌陷及冷热疲劳裂纹),并介绍了模具失效原因及及一些防止措施.通过改进热处理工艺,提高了模具使用寿命.     

蒲河水系来水量分析

本文根据沈北新区所辖范围内的水库及水文站资料,对蒲河水系的来水量进行了分析,为本地区水资源开发利用、保证工程项目的用水量需求提供了科学依据。     

噪声在图像和幻方置乱中的影响

针对噪声在数字图像及图像置乱技术中的影响能力,通过对图像施加一定量的随机噪声,揭示噪声在数字图像及图像置乱技术中的影响能力,从而阐明噪声对图像及幻方置乱技术的危害性和破坏性.也为以后的噪声研究提供试验数据.     

Effects of convective fluid motion upon oxide crystal growth in high temperature solution

For understanding of the influence of convective flow on crystal growth, space high temperature in situ observation instrument (SHITISOI) is dedicated to visualize and record the whole growth process of oxide crystals in high temperature up to 1,000°C. Model experiments using transparent liquids such as KNbO₃ and a mixture of Li₂B₄O₇+KNbO₃ were chosen to investigate effects on ground and in space. On the earth, an investigation of growth kinetics of KNbO₃ crystal related to two different states of convection: diffusive-advective flow and diffusive-convective flow, has been performed. The per unit length of a step e is calculated from the experimental data for two different states of convection. Analyses of these data show the effect of buoyancy convection is to enhance the sharpness of the interface. The growth of KNbO₃ crystals from solution of KNbO₃+Li₂B₄O₇ was investigated in space. The streamlines of the steady thermocapillary convection in Li₂B₄O₇ solvent was observed. Due to thermocapillary convection, KNbO₃ crystal grains grew and filled the whole solution homogeneously. Earth-based quenching experiments are designed in order to study polyhedral instability of KNbO₃ crystal, which is controlled by diffusion mechanism limitation. In all cases, when the crystal was nucleated near air/solution surface, it lost its polyhedral stability and varied from polyhedrons to dendrites. The thickness of diffusion mechanism limitation layer is about 60 μm.     

High yield luminescence of a novel europium complex by excimer excitation and f–f absorption of Eu

A new organic ligand, 2-allyl-1,3-diphenyl-1,3-propanedione (ADP), and the corresponding quaternary Eu³⁺ complex, bi (ADP) (dibenzoyl methane) (1,10-phenanthroline) europium(III) [Eu(ADP)₂(DBM)(Phen)] have been synthesized. Excellent red luminescence from the Eu³⁺ complex was observed excited at 419 nm, and the broad visible excitation band is attributed to excimer absorption. The luminescence quantum yield excited at 419 nm (34 ± 3%) was higher than that at 380 nm (30 ± 3%). This is the first time to find strong and high yield excimer excitation absorption for a europium complex at room temperature, therefore, the excimer absorption band located in visible region (400–500 nm). Moreover, very high yields of direct f–f excitation absorption of Eu³⁺ ions at 466 nm (104 ± 10%) and 536 nm (96 ± 10%) were firstly observed, and the excitation spectrum for the europium complex in solid state is extended in wide region from 220 nm to 580 nm.     

Perfect Single-Crystal Alumina Microspheres

We report the synthesis of perfect single-crystal Al₂O₃ microspheres via direct thermal decomposition of aluminum isopropoxide in air without any template or catalyst. The obtained microspheres were characterized using scanning electron microscopy, X-ray diffraction, transmission electron microscopy, and selective area electron diffraction. The results suggested that the formation of the spheres can be attributed to a transition from polycrystalline to single-crystalline symmetry during high-temperature annealing. The obtained microspheres could be useful for many applications such as lubricants and polishing mediums.     

浅谈化学水处理设备衬胶损坏的修补

橡胶衬里被广泛用于火电厂除盐水及凝结水精处理装置中,但是随着设备使用时间的延长会出现,诸如橡胶衬里与金属脱离,橡胶与橡胶之间脱层,胶面起鼓泡、龟裂、针孔、等缺陷,对这些缺陷必须及时进行修补,否则将影响设备的使用寿命及水质.文章介绍了交换器橡胶衬里的常见损坏及修补办法.