DCJ袋式除尘机组在水电站上的应用

为了保证水电站发电机组的绝缘性,发电机组每个刹车片处都配有除尘装置,文章结合清江隔河岩水电站实际应用案例,介绍了国内应用在发电机组上的除尘机组的工作原理、结构及实际应用效果。     

木结构墙体建造细节对其隔声性能的影响

木结构墙体隔声是木结构居住建筑的一项重要性能. 为了制造出高隔声性能的墙体,该文分析了木结构墙体建造细节对其隔声性能的影响. 研究表明,影响木结构墙体隔声的因素有墙板的面密度、墙骨的规格和间距、玻璃纤维棉的容重和厚度. 木结构墙体的第一共振频率一般都在100 Hz以上,建议选择600 mm作为木结构墙骨间距. 最后得到了在测试频率范围内木结构墙体隔声的变化曲线.      

三芯绝缘导线束的电气参数的理论计算与分析

绝缘导线束是将多股相互绝缘的导线平行连接在一起的一种新型导线结构。三芯绝缘导线束是针对我国农村偏远地区用电负荷少、分散、损失率高的现状，采用低压侧中间抽头的单相配电变压器两火一零供电模式配套而研究和设计的一种新线材。应用电磁场理论和电力架空线路设计的理论，针对三芯绝缘导线束进行电气参数理论计算和分析，结果表明：与常规裸导线相比，其电抗和电纳分别为0．23倍和10倍。分析结果为新型导线的生产和应用奠定了理论基础。     

具有温度约束的设备双层保温经济厚度计算

对于设备保温而言，两层保温材料夹缝处的温度即为外层保温的最大可能使用温度，而该蔡同时受到内，外层保温材料厚度变化的影响。为得到双层保温材料的经济厚度，就要合理调整内，外层保温材料厚度，根据传热学原理，建立了具有温度约束时的双层保温最优化目标函数和约束条件，采和内部惩罚函数法对约束最优化问题进行了求解。     

埋地管道防腐保温结构的适应性

论述了在有保温层条件下，埋地热输管道钢管自身的弹性结构与防腐保温结构的适应性。从防腐保温层和保护层强度、层间粘结力及钢管与防腐层之间粘结力着手，选择材料和防腐保温层结构，使管道获得土壤的约束力，确保管道稳定性。从防腐保温层材料的抗拉强度、抗压强度、热胀特性及各层间的粘结力着手，研究热胀冷缩的同步性，使管道在热变形条件下，确保管子与保温层之间不滑脱或防腐保温层不产生开裂。经输送稠油管道现场检测证明：     

风障对茶园的减风增温效果及对茶树冠层叶片含水率影响

为解决冬季茶园风寒冻害问题,于2008年1月在安徽农业大学茶场建立塑料薄膜风障,测定风障对茶园的减风增温作用及其对茶树冠层叶片含水率的影响。风障的高度为2.0 m,以5×7网格点测定2.8、2.0 m风障高和1.2 m茶树冠层高度3个层次的风速,以4×4网格点测定地表温度、茶树冠层叶片含水率。结果表明,2.8 m高度,风障上方的风速比环境风速增加30%左右,下风方向的减风作用随风速增大而减小,距离风障7 m区域是风速减弱最强的区域,环境风速2.6 m/s时中轴线风速减小13.5%,环境风速1.0 m/s时     

混合气体的正协同效应及其应用

混合气体的耐电强度大于其中任意一种气体的耐电强度则称为正协同效应．这种效应的作用是非常重要的、以实验的方法研究了在不同电场、不同压力、不同局部压力比的条件下SF6和CCl2F2二元混合气体的电击穿特性与SF6／N2、SF6／CO2和CCl2F2三元混合气体电击穿特性之间的关系。试验结果表明在最佳混合压力比的情况下.SF6／N2／CCl2F2．SF6／CO2／CCl2F2三元混合气体的耐电强度能被提高或接近到SF6的耐电强度．同时它的成本接近于SF6／N2=50／50二元混合气体的成本。     

The

This paper describes a digitization detection method harmonic analysis method which is used for detecting the dielectric loss of the electric equipments.The principle of this method and its characteristics of hardware circuits are introduced also.The testing results in the lab and the field show that this method can measure the dielectric loss rather stably and accurately.     

Manufacture and properties of ultra-low-density fiberboard

Low-density fiberboards with densities ranging from 0.05 to 0.50g/cm³ were manufactured with steam injection pressing. Bond-type and foam-type isocyanate compound resin adhesives were used separately at 10% and 30% resin content levels. Two types of different-size fibers from softwood were used. Mechanical, dimensional, thermal, and sound insulation properties of the fiberboards were tested. The results are as follows: (1) Bond-type isocyanate adhesive showed higher mechanical and dimensional properties of low-density fiberboards than the foam-type adhesive. (2) Fiberboards produced from small fibers have better mechanical and dimensional properties than those made from large fibers. (3) Thermal conductivity of fiberboards depends more on the board density than on the type of resin or fiber dimension. At a board density lower than 0.2 g/cm³, the thermal conductivity is almost equivalent to those of thermal insulation materials such as polystyrene foam and rock wool, (4) Generally, the sound absorption coefficient of low-density fiberboards tends to increase at higher sound frequency. As the board thickness increases, low-frequency sounds are more readily absorbed by boards.Part of this report was presented at the 46th annual meeting of the Japan Wood Research Society, Kumamoto, April 1996     

聚氨酯硬泡体材料在高大平房仓中的应用

温度对粮食的品质以及粮食在储藏过程中品质的变化都有较大的影响,因此解决好仓房保温隔热环境是安全储存的保证.试验结果表明,采用在室内仓顶棚喷涂聚氨酯硬泡体材料,仓房的气密性得到改善,对粮温起到了一定的控制作用.