The invention discloses a grounding knife rod balance mechanism, a grounding knife rod mechanism and a grounding switch. The balance mechanism comprises more than one pair of driving gears, and the tooth surfaces of the two driving gears in the same pair are arranged in a face-to-face or back-to-back manner in the axial direction of a rotating shaft. As the two driving gears in the same pair are arranged in a face-to-face or back-to-back manner, the component forces of the meshing forces borne by the two driving gears in the same pair in the axial direction of the rotating shaft offset each other during back-and-forth pitching and swinging of a grounding knife rod in order to avoid axial endplay of the rotating shaft caused by the component force of meshing transmission force in the axial direction of the rotating shaft. Therefore, the grounding knife rod connected to the rotating shaft does not shift in the axial direction of the rotating shaft, and the reliability of meshing between the driving gears and balance gears is improved. The grounding knife rod balance mechanism of the invention has the advantages of more accurate action of grounding knife rod opening and closing and high stability of meshing transmission.

Objective To analyze monitoring features of hepatitis B in Caoxian so as to provide guidance for local preven-tion and control hepatitise B. Methods From the national disease surveillance information management system and from Shandong province immunization planning information system, the data of hepatitis B epidemic and vaccine inoculation of hepatitis B were collected. Combined with the data of the immune level survey of hepatitis B, the data of hepatitis B epi-demiological characteristics were observed. Results Of 2010-2014, the hepatitis B reported incidence was from 27.76/lakh to 39.82/lakh respectively and the cases mainly concentrated in the ages of 20~60 years old groups. The different annual neonatal hepatitis B vaccination rate was from 89.59%to 99.56%,and the timely coverage rate was from 84.76% to 96.71%, significant differences found. The hepatitis B surface antigen positive rate of the preschool children was 2.47%, and the hepatitis B surface antibody positive rate was 73.24%. Conclusion The local hepatitis B virus epidemic intensity was low, mainly in sporadic. The neonatal hepatitis B vaccination rates had reached the national related requirements. The preschool children surface antibody was in a higher level.

This paper describes the background and significance of development of 1100 kV disconnector, and the problems and their solutions for round condoctor-the key part of GW27-1100 type UHV disconnector, a brief introduction of the application in 1100kV UHV Nanyan substation.

通过频率对隔离开关绝缘水平、温升及额定峰值耐受电流等主要性能的影响分析,较详细地介绍了可满足50 Hz和60 Hz兼用的GW4B-252D/J2000型隔离开关的设计、试制及试验等研制情况,为下一步的同类隔离开关的研制提供了参考.

According to China's UHV DC transmission project on the low side DC disconnectors mechanical, electrical resistance, earthquake and other performance requirements,detailed descript the ZGW5-100D/J5500 type HVDC disconnectors design, prototype development, testing and other situations. Experimental results show that the developed ZGW5-100D/J5500 type HVDC disconnectors technical parameters and performance indicators etc. can meet current UHV DC transmission project requirements.

According to problem of GW4 type disconnector from market,such as about temperature rise,torque etc.,utilize tolerance's analysis way,points out that the difference caused by parts' tolerances between the disconnector product and the theory of design, is the main reason of degrade the performance in service, and gives some advices on disconnector adjusting.

根据我国特高压直流输电工程对低压侧直流隔离开关机械、电气、耐地震等性能的要求，较详细地介绍了ZGW5-100D/J5500型高压直流隔离开关的设计、试制及试验等研制情况。试验结果表明所研制ZGW5-100D/J5500型高压直流隔离开关的技术参数和性能指标等均满足我国目前特高压直流输电工程的要求。

Taking polar line DC disconnector whinc first applicating in ±800kV UHV DC transmission project for example,detailedly introduce the designing,testing and application of polar-line disconnector.The result of testing proves that the mechanical and electrical performance of polar-line disconnector fulfills the requirement of ±800kV UHV DC transmission project.

It is necessary for Chinese HV switchgears manufacturers to research and develop DC switchgears independently to meet the requirements of the rapid development of DC transmission and transformation projects in China.This paper described the development of DC transmission and the basic information of DC field equipment in China,with the emphases on the low-voltage-side 50 kV DC disconnector's technical performance,parameters,current flux,and transmission design and calculation,as well as selection of DC insulators in order to benefit the development and design of the DC switchgears in China.

介绍了GW□-1050D/J5000-25型高压直流隔离开关的技术参数、产品结构和性能、产品试验情况和主要特点.

介绍了GW□-1050D/J5000-25型高压直流隔离开关的技术参数、产品结构和性能、产品试验情况和主要特点。关键词:高压直流隔离开关触指外压板簧支柱绝缘子深沟带棱

介绍了GW4B-40.5D/J6300-63型大电流隔离开关的技术参数和性能指标、产品结构设计、主导电系统设计及产品型式试验。

<正>在输电设备中,隔离开关类产品作为用量较多的产品,它的结构虽然比断路器简单,也不需要开断大的负荷电流,但是它的运行情况对电网的安全性和可靠性有着重要的影响。为了满足电力系统对大电流、高可靠性的户外高压交流隔离开关的需求,我公司结合国内外先进的隔离开关设计理念,自行设计、研

[Objective]To study the epidemiologic characteristic of measles in Shanxian County during 2004—2007, promote the monitoring system of measles. [Methods]According to the regular system report of infectious diseases, special system report of measles and annual statistics of measles, the data of monitoring and control of measles during 2004—2007 were analyzed by descriptive epidemiology. [Results]124 suspected measles cases were reported during 2004—2007. The investigating rate was 96.77% within 48 hours after the cases were reported, and the completeness rate of investigating was 100%. The serum specimen collecting rate of the suspected cases was 98.39%.106 cases were confirmed. The cases mainly happened in March to May. The preschoolers and school children as well as adults were affected by the disease. [Conclusion]The epidemic pattern of measles was sporadic eases and outbreak cases coexisted, and the measles in some districts affected the measles morbidity of the whole county. The measles routine immunization in right-age group should be enhanced, and the measles surveillance and inspection should be reinforced.

The danger of the moisture content to the SF6 high-voltage apparatus,as well as the enter path of moisture is studied.Through strengthening the management of production on site and drying the whole equipment,the humidity is reduced,the assembly period is shortened and the production quality is improved.

自实施计划免疫以来,某县麻疹发病得到了有效控制,1998～2003年麻疹年发病平均在1/10万以下,降至历史最低水平.但2004年11月至2005年元月,该县发生麻疹暴发流行,发病率为6.52/10万,疫情涉及12个乡镇,占乡镇总数的60%.为探讨其流行因素及规律,制订有效防制措施,指导今后的麻疹防治工作,现将有关情况分析如下.

目的查明单县某小学风疹爆发流行的原因和传播特征,采取有效措施尽快控制疫情.方法利用流行病学调查方法,结合临床特征和实验室检查等进行统计分析.结果该次风疹爆发流行共发生76例风疹病人,罹患率2.96%;流行高峰在1月15～24日,发病53例,占69.74%;病例以8～10岁学生为多,占75.10%.主要以二、三年级为主,占72.31%.76例病人中有67.11%未接种过风疹疫苗.结论免疫空白和疫情迟报是该次爆发流行的主要原因.加强对重点人群传染病知识的宣传,广泛开展风疹疫苗接种是控制风疹疫情最有效的手段.

在消灭脊髓灰质炎(脊灰)证实工作的最后阶段,为改善今后脊灰的防治工作提供依据,对我县1999-2002年急性弛缓性麻痹(AFP)病例有关资料进行分析.