表面修饰纳米SiO_2/XLPE的电导电流和空间电荷特性

为研究纳米颗粒表面修饰对纳米二氧化硅/交联聚乙烯(SiO2/XLPE)电导电流和空间电荷特性的影响,分别将未经表面修饰和经钛酸酯偶联剂TC9修饰的纳米SiO2颗粒添加到XLPE基体中进行了实验。显微观测和成分分析表明,TC9的非极性有机官能团取代了纳米SiO2颗粒表面的羟基,降低了羟基间的相互成键作用,从而改善了纳米SiO2与XLPE基体之间的相容性,纳米SiO2颗粒在XLPE基体中的粒径范围从几十到100 nm;同时,TC9表面修饰提高了纳米SiO2/XLPE复合介质的介电常数和介质损耗,降低了电导电流,抑制了空间电荷的注入;而未经表面修饰的纳米SiO2/XLPE复合介质的电导电流和空间电荷特性相较于XLPE并未得到改善。分析认为,由于经TC9表面修饰的纳米SiO2分散性的改善,增大了纳米颗粒与XLPE基体之间的界面区域,因而在纳米复合介质内产生了更多的深陷阱;电极与介质界面附近的大量深陷阱捕获注入的电荷,形成固定的空间电荷层,降低了其与电极间的局部电场,从而提高了注入势垒,抑制了空间电荷的进一步注入。     

有机硅钻井液在河南张店油田的应用

河南油田张店地区地层黏土矿物含量高达60%～70%,地层倾角大,钻井过程中存在严重的地层造浆和井塌问题.由实验优选出高分子量聚合物、GW-1、OSAM-K及膨润土加量,形成了有机硅钻井液.经过在张店油田南38区块4口井中的应用表明,有机硅钻井液能有效地抑制地层造浆,防止井壁坍塌,减少井下复杂情况.应用有机硅钻井液的井,钻井液密度低,井径扩大率小,没有出现井塌、划眼和起下钻遇阻卡现象,4口井电测一次成功,没有因造浆外排钻井液.     

Characterization and comprehension of corona partial discharge in air under power frequency to very low frequency voltage

For the partial discharge test of electrical equipment with large capacitance, the use of lowfrequency voltage instead of power frequency voltage can effectively reduce the capacity requirements of test power supply. However, the validity of PD test under low frequency voltage needs to be evaluated. In order to investigate the influence of voltage frequency on corona discharge in the air, the discharge test of the tip-plate electrode under the frequency from 50 to 0.1 Hz is carried out based on the impulse current method. The results show that some of the main features of corona under low frequency do not change. The magnitude of discharge in a positive half cycle is obviously larger than that in a negative cycle. The magnitude of discharge and interval in positive cycle are random, while that in negative cycle are regular. With the decrease of frequency, the inception voltage increases. The variation trend of maximum and average magnitude and repetition rate of the discharge in positive and negative half cycle with the variation of voltage frequency and magnitude is demonstrated, with discussion and interpretation from the aspects of space charge transportation, effective discharge time and transition of discharge modes. There is an obvious difference in the phase resolved pattern of partial discharge and characteristic parameters of discharge patterns between power and low frequency. The experimental results can be the reference for mode identification of partial discharge under low frequency tests. The trend of the measured parameters with the variation of frequency provides more information about the insulation defect than traditional measurements under a single frequency (usually 50 Hz). Also it helps to understand the mechanism of corona discharge with an explanation of the characteristics under different frequencies.     

偶氮苯聚合物（PGMAA-20）膜光栅结构的分子取向机制

设计合成及表征了一种含偶氮苯聚合物(PGMAA-20)材料．利用两束S偏振光作为泵浦光在PGMAA-20膜上刻写光栅并观察光栅的衍射信号；然后再用相衬显微镜直接观察偶氮苯薄膜上的光栅结构，并以分子取向机制为基础对光栅形成和消除过程提出了新解释，这种观点被实验观察结果进一步证实．     

浅谈企业质量体系认证后存在的问题与对策

攀钢针对企业体系认证后存在的问题 ,改进和完善质量体系建设的新途径和新方法 ,并加以实践和推广。切实提高质量保证能力 ,增强了产品市场竞争力     

火箭炮定向管平行度测量研究

本文提出了火箭炮定向管平行度测量的内容,明确了利用激光准直技术进行测量的总体指导思想,提出了几个进行平行度测量的方案,为研制工作打下了基础.     

化学事故应急救援案例

事故 2007年3月30日,沪杭高速公路上,一辆车牌为浙J24010的10吨货车,在与护栏碰撞磨擦近百米后,撞上嘉凤公路永丰桥桥墩,引起车上满载的化学物品燃烧、爆炸,导致驾驶员与押运员全部死亡.面对满车燃烧还不时发生爆炸的化学物品,民防、消防及高速公路交警全力处置,3个多小时后控制了事故,避免了事态进一步发展.     

让收益与节能比翼齐飞——论化工行业节能减排的实现

如何保障节能减排与收益增长的双赢,是现代经济发展的重要议题,对资源消耗、污染严重的化工企业尤为重要。笔者在文中分析了我国化工行业节能减排情况,就节能减排存在问题进行分析,并在此基础上提出相关实现的策略。     

直流电场下低密度聚乙烯纳米介质空间电荷特性的数值分析(英文)

The dynamic characteristics of space charge in nanocomposite of low-density polyethylene (LDPE) mixed with inorganic nano- fillers. Different from previous qualitatively theoretical works, we investigated the influence of trap depth, trap volume charge density and injection barrier height on the space charge and the electric field distribution in the nanocomposite under a DC external electric field (100 MV/m) systematically and quantificationally, through numerical simulations based on a bipolar charge transport model. The simulation re- sults showed that, the increase of trap depth would severely distort the balanced electric field distribution with the highest and the lowest electric field of 119 MV/m and 47 MV/m, respectively. It is concluded that the introduction of nanofillers creates more deep traps, which would block space charges by capturing most of them in the vicinity of electrode and hence reduce the local electric field largely. Further theoretical analysis of the simulation indicates that both the high permittivity and the low local electric field of the nanocomposite contri- buted to the increase of injection barrier height, and almost no charge could overcome an injection barrier higher than 1.25 eV. At last, a mechanism of space charge suppression in the LDPE nanocomposite was presented.