大型火力发电厂煤斗梁承重架搭设施工技术

大型火力发电厂钢筋混凝土煤斗粱不仅截面大、重量重而且施工难度大，是电厂施工中仅次于汽机基座的重要部位。以华能金陵电厂二期工程为例，阐述了钢筋混凝土煤斗梁承重架的搭设方法，     

洛惠渠洛西干渠存在的问题与解决对策

根据洛惠渠洛西干汇多年来的运行实际，分析了工程存在的主要问题，从工程及管理两方面了解决问题的对策。     

美国商业信息

CIVCO公司的Surgi牌外科手术用长度转换器罩,为超声波专家提供了一种安全和简便的准备手术中超声波检查用的转换器的手段。Surgi罩的长度为96英寸,采用耐用的2英丝厚的聚乙烯材料制成,用于手术中的各种超声波检查,包装为方便的手风琴样式,配有手提袋的无菌的弹性带子。     

渠井双灌区水资源管理途径的探讨

泾惠渠灌区是一个渠井结合的大型灌区。渠水和井水两种水源相互补充 ,为灌区的农业丰收提供了有力的水源保证。但随着农村联产承包责任制的实施和市场经济的发展 ,两种水源由于缺乏统一管理 ,开发、利用矛盾日趋突出 ,已成为制约灌区农业经济发展主要因素之一。为此 ,作者对水资源管理作了探讨。     

长排摩擦型高强度螺栓连接接头的研究

本文根据九江长江大桥钢梁接头设计中出现的长排摩擦型高强度螺栓连接问题,特通过对长、短排螺栓接头的对比试验,探明了不同接头的变形特征,得出了长排栓连接的单栓承载力,不需要象承压型接头那样,随排数增多而折减的结论。而且研究中所提出的判断滑移准则、接头传力比参数、应力集中系数等计算方法,试验表明科学合理,能很好地解释接头的疲劳破坏现象。     

新颖两性聚合物复鞣剂DR的合成研究

利用二乙基二烯丙基氯化铵(DEDAAC)和甲基丙烯酸等乙烯基类单体(VM)在引发剂过硫酸铵(APS)的作用下，在水溶液中通过共聚合反应制得了一种两性树脂鞣剂，研究了各种聚合条件，如引发剂和单体浓度对共聚合反应的影响。同时用红外光谱(FT-IR)、热失重(TGA)、透射电镜(TEM)对聚合物的结构和性能进行了表征，并进行了应用试验。应用结果表明：该复鞣剂无败色现象，有一定的选择填充性，收敛性小，鞣后成革手感丰满、柔软、革面平细。     

Position Adaptive Measurement Model for Double-four Quadrant Photoelectric Detector

A modeling method of the support vector machine combined with matrix optics is considered; a complete new measurement model for double-four quadrant photoelectric detector is built. According to the analysis of the received light spot size and its motion with the changes of the defocusing amount of detector photosensitive surface and the detector position attitude in the optical path, a mathematic expression of photoelectrical conversion is given, which can be applicable to random setting position of the detector at any time. Based on least square support vector machine （LS SVM）, the mapping relationship among the output signal linear characteristic parameters （zero neighborhood gradient and intercept）, the defocusing amount of the detector and the installation position attitude angle is established. Thus, the multiple dimensional high accuracy measuring and adjusting control system can be left out, and adaptive measurement of the detector parameters can be realized. Compared with existed measurement model and method, the presented model has the advantages of more clear physical meaning, closer to work mechanism of detector, acquiring more complete sample data and wiping out the dead spots or bad spots in measurement. And the accuracy of displacement measurement is increased to 3μm. At the same time, this measurement mode provides a technical shortcut for three-dimensional small angle measurement.