检索结果-南通市图书馆

Distribution Characteristics and Shielding Effects of Ion Clouds

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Meteorological and Environmental Research 2023年第2期14卷 42-44,49页

作者： Hui YANG Zhongqiu SHI Renhong GUO yixian qiu Qiaobin WEI Yu HUANG Guangzhou Meteorological Bureau Guangzhou 510530China Guangdong Yuedian Zhuhai Offshore Wind Power Co. Ltd.Zhuhai 519040China Guangdong Yuedian Yangjiang Offshore Wind Power Co. Ltd.Yangjiang 510630China Guangdong Foshan Shunde Lunjiao Jindun Lightning Protection Technology Development Co. Ltd.Foshan 528308China

The latest research shows that the ions generated by the corona discharge of lightning rod have dual functions of attracting and shielding lightning discharge. After the lightning rod is installed at a certain height on the ground,the lightning rod tip reaches the corona threshold to ionize the surrounding air and generate positive and negative ions under the action of the electric field at the end of the lightning downward leader. Constrained by Coulomb’s Law,its positive ions( opposite charges attract each other) form an upward leader( streamer),which moves towards the end of the lightning downward leader and is connected to the downward leader,establishing a discharge channel to attract lightning to the needle tip and discharge the current to the ground,and playing a role in attracting lightning. Its negative ions are repelled by the electric field at the end of the lightning downward leader( repelled by isotropic charges) and influenced by the wind,and diffuse in the downwind area to form an ion cloud,inhibiting the growth of corona at the tip of ground objects,and playing a role in shielding lightning. In this paper,Franklin’s understanding of the role of lightning rod and Yang Shaojie’s new definition of the working principle of lightning rod are briefly introduced. The formation mechanism,distribution characteristics,shielding effect,and impact on lightning strike point distribution of ion clouds are analyzed. Additionally,the important role of shielding effects of ion clouds in regional lightning protection is introduced,which provides a theoretical basis for the correct understanding and use of lightning rod.

关键词： Lightning rod Ion clouds Distribution characteristics Regional lightning protection Theoretical basis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

基于控制点的玉米雄穗生长形态建模

计算机工程与应用 2004年第9期40卷 203-205页

作者：李磊刘晓东罗轶先秋林西安交通大学生态环境与现代农业中心西安710049

介绍了一种绘制玉米雄穗的方法,主要结合了图形学和数学方面的有关知识,通过设置控制点以及调整坐标来进行玉米雄穗生长过程建模,在虚拟现实显示平台中很好地展示了玉米雄穗的形态和生长过程。

关键词：虚拟现实 OpenGL 玉米雄穗控制点

Analysis on Lightning Strike Cause of Directly Buried Optical Cable in Wind Farm and Its Prevention Methods

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Meteorological and Environmental Research 2022年第3期13卷 67-70页

作者： Yan YANG Zhen CHEN yixian qiu Yu HUANG Qiaobin WEI Shaojie YANG Shenzhen Meteorological Bureau Shenzhen 518000China Guangdong Wind Power Co. Ltd.Guangzhou 510630China Guangdong Foshan Shunde Lunjiao Jindun Lightning Protection Technology Development Co. Ltd.Foshan 528308China Guangdong Meteorological Bureau Guangzhou 510080China

Directly buried metal optical cable is a form of erecting optical fiber ring network communication system in wind farms. Although the directly buried optical cable is much less than the overhead optical cable affected by lightning, sometimes lightning damaging optical cable and flashover discharge accidents of optical cable port occurred. In this paper, the amplitude spectrum of lightning wave, the breakdown depth and breakdown distance of lightning wave to soil, the metal components of optical cable port and the impedance characteristics of grounding wire are systematically analyzed, and the prevention methods of directly buried optical cable in wind farm to avoid lightning damage are proposed.

关键词： Wind farm Directly buried optical cable Lightning stroke accident Prevention method

Analysis on Attenuation Efficiency of Lightning Current by Lightning Interceptor

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Meteorological and Environmental Research 2023年第1期14卷 56-59页

作者： Hui YANG Zhongqiu SHI Renhong GUO yixian qiu Qiaobin WEI Ruping ZHOU Yu HUANG Guangzhou Meteorological Bureau Guangzhou 510530China Guangdong Yuedian Zhuhai Offshore Wind Power Co. Ltd.Zhuhai 519040China Guangdong Yuedian Yangjiang Offshore Wind Power Co. Ltd.Yangjiang 510630China Shunde District Meteorological Bureau of Foshan City of Guangdong Province Foshan 528300China Guangdong Foshan Shunde Lunjiao Jindun Lightning Protection Technology Development Co. Ltd.Foshan 528308China

Lightning interception technology is one of the three core technical systems of regional lightning protection *** them,the omni-directional multi-pulse lightning interceptor(hereinafter referred to as lightning interceptor,the same below)has the ability to attenuate lightning current≥40%and significantly reduce the intensity of the spatial electromagnetic field around the lightning *** order to explore the attenuation mechanism and effect of lightning interceptor to lightning current,this paper analyzed a lightning stroke process at 16:00 on August 19,2022,and tried to explain the attenuation effect of lightning interceptor to lightning current with the physical parameters of lightning stroke.

关键词： Lightning interceptor Lightning current Attenuation efficiency Case analysis

Three Core Technical Systems and Engineering Application of Regional Lightning Protection

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Meteorological and Environmental Research 2023年第3期14卷 48-53页

作者： Zhen CHEN Yu HUANG Ziqin GAO yixian qiu Xiaofeng LUO Xiaoning ZHANG Jixi LIU Guangdong Yuedian Dianbai Wind Power Co. Ltd.Maoming 525400China Guangdong Foshan Shunde Lunjiao Jindun Lightning Protection Technology Development Co. Ltd.Foshan 528308China Guangdong Yuedian Yangjiang Offshore Wind Power Co. Ltd.Yangjiang 510630China Henan Wangding Lightning Protection Device Safety Testing Co. Ltd.Zhengzhou 450003China

Regional lightning protection is a complete theoretical system,mainly including:lightning interception technology(LIPT),lightning strong electromagnetic pulse high-energy absorption technology(MSPD),and regional lightning activity law analysis technology(RLLA).Lightning interception technology uses dispersive waveguide resonant cavity technology to achieve the functions of 46.55 m longer than upward leader of ordinary lightning rod,significantly reducing lightning strike point current by 40%,optimizing space electromagnetic field environment,and effectively intercepting overhead and side lightning strikes,and overcome the limitations of traditional lightning *** lightning strong electromagnetic pulse high-energy absorption technology uses distributed parameter balance technology,special disconnector for short circuit current,and parity pairing technology to achieve stronger surge absorption capacity than traditional single pulse SPD and international advanced technical indicators such as timely breaking under power frequency short circuit current,and good energy and time *** analysis technology of regional lightning activity laws accurately identifies lightning strike points through comprehensive analysis of regional lightning activity laws,physical parameters of ion clouds,and the impact on ground electric *** three core technology systems complement each other,achieving all-round protection against direct lightning strike and lightning electromagnetic *** projects achieved zero lightning damage,effectively ensuring the safety of buildings and electronic and electrical equipment in the protected area.

关键词： Regional lightning protection Lightning interception technology Multi-pulse high-energy absorption technology Lightning point identification technology

Application of Comprehensive Lightning Interceptor in Highway Toll Station

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Meteorological and Environmental Research 2022年第5期13卷 56-59页

作者： Zaiqiang YANG yixian qiu Yu HUANG Lingjin KONG Ruiliang CHEN Yan YANG Hui YANG Shandong Expressway Traffic Engineering Co. Ltd.Binzhou 256600China Guangdong Wind Power Co. Ltd.Guangzhou 510630China Guangdong Foshan Shunde Lunjiao Jindun Lightning Protection Technology Development Co. Ltd.Foshan 528308China Shenzhen Meteorological Bureau Shenzhen 508000China Guangzhou Meteorological Bureau Guangzhou 510080China

Expressway toll station is listed by lightning protection experts as one of the five difficult problems in the field of international lightning *** far,the direct lightning protection of the expressway toll station is mainly based on the electrical geometry model-rolling ball *** rod or lightning belt is installed on the high pole lamp of the toll square and the ceiling of the toll island as a flash catching device to intercept *** lightning rod is a section of metal conductor with the *** the process of the connection between up leader generated by the lightning rod and down leader of lightning,the lightning rod has the ability to attract the lightning rod,and can prevent lightning strike of the protected objects within a certain *** the perspective of lightning protection methods and means,lightning protection plays an interception role against lightning discharge,also called interceptor.A large number of practice has proved that the lightning rod plays an important role in protecting the building structure from lightning *** the development of electronic information society,the limitations of lightning rod are more and more prominent,resulting in more and more lightning strike *** 2019,China invented a new flash connection device-lightning interceptor that can overcome the limitations of lightning rod and has applied it on expressways,which has achieved remarkable *** this paper,the physical parameters of lightning receiving process by the lightning interceptor and the lightning rod are compared,and the solution to prevent direct lightning strike at expressway toll station is proposed.

关键词： Highway Lightning rod limitations Lightning interceptor Multi-pulse discharge Continuous current

Limitations of Lightning Rods in Preventing Direct Lightning Strikes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Meteorological and Environmental Research 2023年第4期14卷 59-62页

作者： Zhen CHEN Xiaofeng LUO Jixi LIU Ziqin GAO yixian qiu Xiaoning ZHANG Lingjin KONG Chunliang ZHANG Guangdong Yuedian Dianbai Wind Power Co. Ltd.Maoming 525400China Guangdong Yuedian Yangjiang Offshore Wind Power Co. Ltd.Yangjiang 510630China Henan Wangding Lightning Protection Device Safety Testing Co. Ltd.Zhengzhou 450003China Guangdong Foshan Shunde Lunjiao Jindun Lightning Protection Technology Development Co. Ltd.Foshan 528308China

Since ancient times,lightning disasters have undoubtedly been an unstoppable threat to *** thunderstorms,lightning often damages objects on the ground,such as buildings and *** Franklin invented the lightning rod in 1752,lightning rods have been used worldwide to prevent direct lightning strikes in various fields such as high-voltage power transmission lines,outdoor chemical sites,highways,land and sea wind farms,and forest lightning fire *** has been proven that lightning accidents still occur frequently in places where lightning rods are installed and the protective angle method is *** order to further study the protective effect of lightning rods and identify the shortcomings of lightning rod protection,negative lightning strikes are taken as the research object,to analyze the limitations of lightning rods in preventing direct lightning strikes from the working principle of lightning rods.

关键词： Lightning rod Direct lightning strike Protective angle method Limitation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

避雷针工作原理研究

电力系统装备 2023年第6期 66-68,190页

作者：杨晖史忠秋郭仁宏丘翊仙黄昱广州市气象局广东广州510530 广东粤电珠海海上风电有限公司广东珠海519040 广东粤电阳江海上风电有限公司广东阳江510630 广东佛山顺德伦教金盾防雷技术发展有限公司广东佛山528308

避雷针是预防直接雷击的主要技术措施。在高压输电线路、风力发电机、户外化工场所、高速公路等专业领域均普遍使用。大量实践证明,安装避雷针,利用其吸引雷电的作用,采用保护角法进行保护的物体雷击事故依然频繁发生。为了解决上述领... 详细信息

避雷针是预防直接雷击的主要技术措施。在高压输电线路、风力发电机、户外化工场所、高速公路等专业领域均普遍使用。大量实践证明,安装避雷针,利用其吸引雷电的作用,采用保护角法进行保护的物体雷击事故依然频繁发生。为了解决上述领域的雷电灾害难题,气象、电力专家研究了避雷针的工作原理,发现避雷针具有吸引雷电和屏蔽雷电的两个作用。文章以负雷电为例,系统论述了避雷针吸引雷电和屏蔽雷电两个作用的物理过程,对于地面物体进行保护的工程应用方法及效果,重新定义了避雷针的工作原理。

关键词：避雷针工作原理吸引作用屏蔽作用保护角法区域防雷

气相色谱-串联质谱法分析消瘤藤中挥发油成分

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国民族民间医药 2020年第9期29卷 20-22页

作者：陈宇钟盈盈刘佳明卢森华丘一仙广西壮族自治区玉林市食品药品检验检测中心广西玉林537000

目的:研究消瘤藤中挥发油中的主要成分及其含量。方法:采用水蒸气蒸馏法提取消瘤藤的挥发油成分,用气相色谱-质谱联用技术进行测定,结合计算机检索技术对分离的化合物进行结构鉴定并用色谱峰面积归一化法获得各化合物的相对含量。结果:... 详细信息

目的:研究消瘤藤中挥发油中的主要成分及其含量。方法:采用水蒸气蒸馏法提取消瘤藤的挥发油成分,用气相色谱-质谱联用技术进行测定,结合计算机检索技术对分离的化合物进行结构鉴定并用色谱峰面积归一化法获得各化合物的相对含量。结果:从消瘤藤中鉴定出27个成分,占挥发油总量的87.73%,相对含量较高的挥发油成分有棕榈酸(46.96%)、亚油酸(16.02%)、反油酸(5.12%)、顺-9-六癸酸(2.75%)、肉豆蔻酸(2.25%)、正十五酸(2.24%)。结论:本研究通过对消瘤藤挥发油成分的气相色谱-质谱联用分析,为其综合开发和利用提供科学依据。

关键词：消瘤藤挥发油气相色谱-串联质谱