炼钢电弧炉变压器安全运行

目前国内35KV以下的电弧炉变压器普遍采用真空断路器作为操作开关,但其最大缺点就是操作过电压较高,当无任何保护时,可达额定电压的4～5倍;为了降低真空断路器的操作过电压,对于已使用的真空断路器必须同时加设P—O吸收装置和MOA     

真空断路器操作过电压分析与限制措施

真空断路器在开断感性负荷时,将产生操作过电压,对电动性带来积累性损伤,为限制操作过电压,国内大都采用过电压保护器,文中对各类过电压保护器适用范围进行比较,明确其用途。     

操作过电压保护器故障分析和防治方法

主要分析了包钢供电厂因操作过电压引起的几起过电压保护器故障原因,进一步阐述了Y型MOA过电压保护器和Y型R-C阻容保护器自身存在的技术问题,指出了操作过电压对设备的危害性,并提出了防治办法.     

高压电动机过电压保护存在的问题和改进措施

本文介绍了高压电动机运行过程中产生的操作过电压及其危害 ,对我厂现有保护 (MOA)的缺陷进行分析 ,同时展望新型MOP相间过电压保护器在我厂的应用前景。     

ZR阻容吸收器防止真空断路器操作过电压的应用

本文通过对真空断路器的操作过电压的形成和特性进行分析，论述了ZR阻容吸收器在防止真空断路器的操作过电压上的应用。     

真空断路器的应用

根据真空断路器逐步取代少油断路器的发展趋势，分析了真空断路器在运行中产生操作过电压的原因并论证了解决方法。     

太钢电弧炉上应用四星接法MOA的必要性

分析了太钢电弧炉变压器高压侧相间过电压的产生原因，比较了用于限制过电压的避雷器的两种接法．结论是用四垦接法ＭＯＡ限制过电压的效果较显著．     

真空断路器操作过电压及其限制措施

详细分析了真空断路器在切断电感性负载时产生操作过电压(截流过电压和多次重燃过电压)的机理，并介绍了几种限制过电压的措施。     

真空开关开断电炉变压器产生的过电压及其防护措施

文章介绍了用真空断路器开断电炉变压器产生过电压的原因，并对提出的限制过电压的方法采取了防护和限制措施。     

TBP型三相组合式过电压保护器爆炸原因分析与对策

TBP型三相组合式过电压保护器逐步取代了MOA(氧化锌避雷器)和SiC(碳化硅避雷器),广泛应用在6～35 kV电压等级变配电设施上,由于内部绝缘受潮和串联间隙的位移,运行中爆炸事故常有发生,分析了爆炸产生的原因,提出了避免发生爆炸事故的措施.     

中高压断路器回路电阻阻值超标分析

回路电阻是影响断路器运行质量的基本要素之一，通过分析断路器回路电阻值超标的原因，可有效提高设备安全运行的可靠性。     

35kV户外隔离刀闸故障分析处理及注意事项

通过对35 kV户外隔离刀闸所出现的发热熔断现象进行故障分析、处理,从中总结故障原因,对刀闸的选用及运行维护提出要求,以保障其安全运行。     

硬质合金烧结用双炉体半自动卧式真空炉的设计与应用

本文所述的卧式真空烧结炉采用双炉体共用一套真空系统、供电系统和控制系统,装有微机控制装置,保证烧结过程自动、稳定运行,炉子结构合理,连接可靠,操作方便,具有良好的灵活性和投资低的优点,完全适用于工业生产,并在应用中取得较好的效益。     

氧化锌避雷器运行中防爆问题的讨论

通过对氧化锌避雷器的热过程分析，得出ＭＯＡ在线运行相关物理量的变化规律，从而找出事故原因，并提出相应的防范措施。     

Fabrication and Testing of Cuff Connections for GFRP Box Sections

A new type of connection between beams and columns has been designed and fabricated specifically for use with glass fiber reinforced plastic (GFRP) pultruded box members. The work is built on previous efforts in the area of GFRP connections, which demonstrated that innovative connections between box sections are superior to connections based on concepts from steel construction for connecting I-beams. The new connection element is designed as a monolithic connection for frame members and is fabricated using a vacuum assisted resin transfer molding process. Individual connection specimens have been fabricated and tested to verify their performance under cyclic static loads in a test frame designed to simulate conditions in a moment resisting frame. The connection configuration was found to fare better from the standpoint of both strength and stiffness in comparison with previous attempts at developing GFRP beam-to-column connections.     

The Helicobacter pylori fatty acid cis-9,10-methyleneoctadecanoic acid stimulates protein kinase C and increases DNA synthesis of gastric HM02 cells

Protein kinase C (PKC) has been implicated in the control of epithelial proliferative activity and in the process of malignant transformation. Helicobacter pylori (H.p.) infection is associated with increased gastric epithelial cell proliferation and has been linked with gastric carcinoma. In the present study, we report that the H.p. fatty acid cis-9,10-methyleneoctadecanoic acid (MOA) directly activates PKC (Ka 3.3 microM). The effect of MOA upon PKC activation was Ca2+ dependent but did not require phosphatidylserine as phospholipid cofactor. MOA increased the stimulatory effect of phosphatidylserine at low Ca2+ (1 microM) concentrations. These findings indicate that MOA interacts at the phospholipid- and the diacylglycerol-binding domain to elicit PKC activation. Treatment of gastric mucous cells HM02 caused translocation of PKC from the cytosol to the nuclear, mitochondrial and membrane fraction. Furthermore, MOA stimulated [3H]thymidine incorporation into the DNA of HM02 cells. Our results show that the H.p. fatty acid MOA activates PKC and increases DNA synthesis in gastric epithelial cells.     

敞开式SF6断路器弹簧操作机构的缺陷整改

敞开式SF6断路器岗其结构简单，操作能耗小、安装容易等特点被广泛采用。应用结果表明：SF6断路器关键部件如内动锄头导向环用材不当，二次控制回路设计不合理，为设备重大缺陷，应引起重视。