Results 41 to 50 of about 10,086 (125)

Effective polysulfides regulation in high‐performance Li–S batteries via novel VO2–VS2 heterostructure

open access: yesRare Metals, Volume 44, Issue 6, Page 3772-3783, June 2025.
Graphical abstract AbstractDeveloping effective heterostructure strategies to mitigate the shuttling effect and accelerate lithium polysulfide (LiPS) conversion remains a critical challenge in lithium–sulfur (Li–S) batteries. Here, we report the first carbon–free VO2–VS2 heterostructure material synthesized via in situ sulfurization, applied as a ...
Yao‐Lin Hou   +6 more
wiley   +1 more source

Dams in intrastate ethnic conflict: A comparison of Turkey and Ethiopia

open access: yesWorld Water Policy, Volume 10, Issue 4, Page 1044-1065, November 2024.
Abstract Why do dams exacerbate ethnic conflict in Turkey but not in Ethiopia? This paper analyzes the impacts of a growing push to develop water resources through hydroelectric dams, which promise clean energy, jobs, and economic opportunities. Yet dam building also causes environmental degradation, mass relocation, the flooding of historical sites ...
Alex Bezahler
wiley   +1 more source

基于回声状态网络的接地网地表电位计算

open access: yesGaoya dianqi, 2019
现有基于地表电位的接地网故障诊断需要测量大量的现场数据,为在减少现场测试工作量的同时提高接地网地表电位分布计算的准确性,文中提出了基于回声状态网络的接地网地表电位计算方法。首先利用接地网地表电位计算结果对回声状态网络进行训练,然后根据接地网结构对其进行网孔划分,最后使用少量的现场测试数据输入到每个区域的回声状态网络模型来计算得到接地网的整体地表电位分布。计算结果与某接地网模型的试验结果表明,文中所提方法能得到特定网孔处的接地网地表电位分布计算模型,据此可得到较为准确的接地网地表电位分布 ...
盛青   +5 more
doaj  

Parliament, petitions and pandemic: Conspiracism in Australia's federal e‐petitions system, 2020−2021

open access: yesPolicy &Internet, Volume 16, Issue 3, Page 485-508, September 2024.
Abstract During the COVID‐19 pandemic, some groups and individuals rearticulated state power through conspiracy theories. Despite their fringe status, conspiracy theory beliefs can directly animate citizen's engagements with institutions. Drawing on Barkun's ‘conventional’ and ‘stigmatised’ knowledge types, we analyse the appearance of conspiracism in ...
Ben Lyall, Patrick Marple
wiley   +1 more source

变电站二次电缆双端接地的安全性能分析

open access: yesDianci bileiqi, 2018
变电站接地系统是确保电气设备及人身安全的重要设施,控制电缆连接一次设备与二次设备,其安全性能影响着二次系统的稳定运行。基于不等电位的节点电压法,研究了带有双端接地电缆的地网参数计算模型,并通过matlab编写程序对电缆芯线-屏蔽层电位差进行仿真分析。研究结果表明:芯线-屏蔽层电位差受土壤电阻率影响较小,受电缆长度与地电位升影响较大;在电缆沟中并联铺设铜接地带能有效保护电缆及电气设备安全;综合二次系统绝缘耐受电压与电缆接地方式,可将地电位升提高到5 kV甚至更高。
史柳, 刘骐, 胡全义, 鲁志伟
doaj  

Physicochemical and microbiological assessment of multi‐village drinking water source in diarrheal hotspot areas of north Shoa zone, Amhara region, Ethiopia

open access: yesWorld Water Policy, Volume 10, Issue 3, Page 971-985, August 2024.
Abstract Quality water is essential to people's health and social and economic well‐being. Evaluation of the quality of the water sources provides benchmark data on quality status and insights into the development of further protective measures. A laboratory‐based cross‐sectional study design was conducted in the diarrheal hotspot area of the North ...
Tsegahun Asfaw Abebe   +5 more
wiley   +1 more source

并联直流接地极抑制上海区域直流偏磁的方法研究

open access: yesGaoya dianqi, 2012
在对直流偏磁产生原因及安装于变压器中性点的直流抑制装置进行简述的基础上,考虑上海区域多直流落点和多接地极的特点,提出了用并联直流接地极去抑制上海区域直流偏磁的方法。根据设计单位资料,对并联用特高压奉贤接地极、华新换流站接地极以及南桥接地极建立了电极模型并获取了各500 kV变电站等效电阻。根据上海区域地质结构和土壤电阻率实测数据,建立了由浅沉积层、深沉积层、基岩层以及地幔至地心层组成的4层水平分层土壤模型。以近景年上海区域电网主要拓扑结构,对直流接地极单独运行 ...
顾承昱, 司文荣, 郑旭, 赵文彬
doaj  

高土壤电阻率地区某220 kV变电站接地方案研究

open access: yesDianci bileiqi, 2020
处于高土壤电阻率地区的变电站,其接地网的接地性能难以满足要求。以高土壤电阻率地区某220 kV变电站为例,对其接地方案进行优化设计研究。基于接地分析软件CDEGS,完成了接地网网格优化、二次电缆芯皮电位差的计算及接地深井等降阻措施研究;基于电磁暂态分析软件EMTP,计算了变电站低压避雷器耐受地电位升上限,结合变电站设备的运行参数及规范对接地参数的要求,得到了地电位升允许上限值。最后考虑网格优化、降阻措施和技术经济性,给出了高土壤电阻率地区某220 kV变电站接地网的设计方案。
邢琳   +4 more
doaj  

带电作业人员侵入110kV电缆终端塔间隙方式对套管及应力锥电场分布的影响研究

open access: yesDianci bileiqi, 2022
电缆终端套管是电缆线路的薄弱环节,为了掌握带电作业人员不同侵入电缆终端塔间隙的方式对套管及其应力锥电场分布的影响,根据实际110 kV电缆终端搭建仿真模型,因电缆终端塔和应力锥的尺度差异大采用子模型法来优化计算模型,分析了电缆终端正常运行及带电作业人员处于地电位作业、中间电位作业以及等电位作业3种情况对电缆终端应力锥电场分布的影响。计算结果表明:子模型法在保证计算精度的条件下可以有效减少网格数量和缩短计算时间;应力锥在3种作业方式下的电场变化相对于正常运行时均在3.5%以内 ...
吴田   +4 more
doaj  

基于等效界面电荷的分层土壤结构地电位分析 附视频

open access: yesDianci bileiqi, 2022
直流输电过程中,接地极和大地土壤承担着散流作用,电流散流区域的土壤模型是准确计算地电位和电流场分布的关键,而格林函数是研究土壤模型的重要手段。直流输电工程中的接地极选址问题,一直备受关注,往往选址确定后,极址周围土壤结构基本确定,因此通过接地极位置调整以优化电场、电位分布,降低环境影响,有工程应用价值和研究意义。本研究通过分析基本的水平双层结构土壤模型,将电位分布结果拆分为直接效应和界面电荷积累效应,建立了界面积累电荷分布理论,得到由四种电荷效应构成的系数矩阵,以此分析了某直流输电工程 ...
doaj  

Home - About - Disclaimer - Privacy