测量杆塔冲击接地电阻的研究

在总结现有的杆塔冲击接地电阻的计算测量方法的基础上,研制了便携式杆塔冲击接地电阻测量系统.它首先向接地体注入波头较缓、幅值较低的冲击电流,接着采集接地体的电压与电流信号,经滤波后再换算到标准雷电流下求出其电压响应,最后求出冲击接地电阻.实验室测试结果与传统的冲击接地电阻测量方法对比表明本系统测量方便且可信度高.     

测量线路电流的高相位精度方案的试验研究

设计出以罗哥夫斯基线圈为传感器,加有相位比较环节的工频电流测量系统。通过相位比较环节能大为提高测量的相位精度。从试验结果可看出,该系统可还原电流的波形,并能较为准确的测量出工频电流的幅值,平均误差约为1%,相角差不超过20′。     

Properties of cementitious rendering mortar prepared with recycled fine aggregates

The results of an experimental study on investigating the properties of cementitious rendering mortars prepared with a recycled fine aggregate (RA) were presented. The RA was obtained from a recycling plant in which mixed demolition wastes were processed by mechanical crushing, sieving and sorting operations. Two series of rendering mortar mixes were prepared with a constant water/cement and a constant aggregate/cement ratios of 0.55 and 3 respectively. River sand and natural crushed rock fine were originally used in the two series separately, and they were consistently replaced by 25%, 50%, 75% and 100% by the recycled aggregate. The experimental results showed that mechanical properties, such as compressive strength, flexural strength and modulus of elasticity of the mortars prepared with the RA were lower than the mortars made with the natural aggregates. Nevertheless, the bond strength at the interface between the mortar and masonry bricks determined by the Triplet test was found to be higher for the mortars prepared with the RA.     

ICP-AES法测定氧化铟-氧化锡(ITO)超细复合粉末中的痕量杂质

建立了超细In203-Sn02(ITO)复合粉末中Al，Ca，Cd，Co，Cr，Cu，Fe，Mg，Mn，Mo，Ni，Ti，V，Zn，Zr等15种杂质元素的ICP-AES测定方法．研究了基体对被测元素的干扰，选择了仪器最佳工作参数．方法的回收率为92％～110％，相对标准偏差为0．26％～3．66％．     

累托石层材料在废水处理中的应用研究（Ⅱ）——电镀废水的处理

利用累托石层孔材料处理电镀废水，累托石层孔材料用量5g/L,pH=4，添加剂FS01用量为0.2g/L，搅拌吸附60－90min，处理后水中残留CL^-质量浓度为0.014mg/L，残留Cr^6 质量浓度0.16mg/L；在不改变原水pH条件下，累托石层孔材料用量为2.5g/L，F02用量为0.5g/L，搅拌时间为20－40min，处理后水中残留铬质量浓度为0.2mg/L，累托石加入Pt01试剂后，吸附能力增强，可用于处理各种含Cr^6 电镀废水，当累托层孔材料用量为2g/L,pH=7,Pt01试剂2g/L，搅拌吸附30min时，其吸附率可达98．89％，处理水Cr^6 质量浓度降低到0.3mg/L，动态试验表明，处理后的废液不仅含Cr^6 浓度低，而且颜色几乎无色透明。     

河南油田钻井污水处理实验研究

对河南油田钻井污水采用化学强化固液分离 -絮凝沉降两步处理工艺进行了处理实验 ,确定了工艺条件 ,筛选出了最适宜的药剂配方。实验表明 :河南油田钻井污水经上述工艺处理后水质达到排放要求 (GB8978-1996 ) ,尤其是超高COD得到有效去除 ,从 996 0 .2mg·l-1降低到 15 0mg·l-1以下。     

我国特殊医学用途婴儿配方食品现状浅析

特殊医学用途婴儿配方食品,是根据患有特殊紊乱、疾病或医疗状况等特殊医学状况婴儿的营养需求而设计制成的特殊食品,是这类婴儿赖以生存的主要食物来源.近年来,一些不良企业以固体饮料冒充这类特殊食品坑害婴儿的事件时有发生.为促进社会对特殊医学用途婴儿配方食品的了解,推动产业健康发展,保障特殊医学状况婴儿的生命健康,本研究总结对...     

论大功率激光焊接的研究及应用

本文综述大功率激光焊的特征、激光器生产现状和应用情况。激光焊可在很宽的规范间实现,板厚从几微米到数十毫米的各种金属的焊接,效率高、质量好。