Results 31 to 40 of about 39,483 (195)
Dianci bileiqi, 2019 针对一起复合绝缘氧化锌避雷器部分电阻片劣化后难以利用阻性泄漏电流判定缺陷的案例,利用MATLAB对部分电阻片劣化后的氧化锌避雷器进行了仿真分析,通过对比电阻片在不同劣化程度时,运行电压下通过避雷器的全电流和阻性电流泄漏值,发现当劣化电阻片个数很少时,阻性泄漏电流随着劣化程度的增加存在一个峰值,当劣化程度继续增加,过了这个峰值后难以通过带电检测得到的阻性电流泄漏值判定出少数电阻片严重劣化的避雷器缺陷,仿真结果与缺陷案例吻合。因此,根据仿真结果,提出结合在线监测下的全电流值是否超过初始值10 ...
杨帆 +4 more
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Veterinary Dermatology, Volume 35, Issue 3, Page 325-336, June 2024.Background – Norway spruce (Picea abies) resin‐based products are used in human medicine. A resin‐based otic rinse also could be useful in supportive care of canine otitis externa (COE), yet information on its antimicrobial effect against canine pathogens or ototoxicity is lacking.
Elina Aimo‐Koivisto +5 more
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Dianci bileiqi, 1977 本文就本世纪二十年代前后日本悬式绝缘子的劣化情况作了论述。并总结了绝缘子的劣化原固及其后来的改进措施。文中还介绍了从实际输电线路上取下来的劣化绝缘子的分析情况,提出了可供参考的绝缘子劣化的有益数据。
新宫行太, 姜惇
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Gaoya dianqi, 2022 近年来,复合绝缘子酥朽断裂问题引起了学术界及工业界的高度重视,但断裂原因一直莫衷一是。研究表明了复合绝缘子酥朽断裂的原因可能包括湿气侵蚀、电蚀、酸性介质腐蚀等因素。针对湿气侵蚀因素,文中研究了复合绝缘子芯棒在湿热条件下的劣化过程。首先观察了芯棒湿热作用后芯棒的宏观形貌,发现芯棒呈现发黄发白的颜色,质地变得疏松,形如腐朽的木头。随后对芯棒在高湿环境下的发热情况进行了观测,发现劣化后芯棒的温升明显高于未劣化芯棒的温升。通过扫描电镜(SEM)、傅里叶红外光谱(FTIR)、热失重分析(TGA ...
王成 +5 more
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Understanding consumers to inform market interventions for Singapore's shark fin trade
People and Nature, Volume 6, Issue 2, Page 733-748, April 2024.Abstract Sharks, rays and their cartilaginous relatives (Class Chondrichthyes, herein ‘sharks’) are among the world's most threatened species groups, primarily due to overfishing, which in turn is driven by complex market forces including demand for fins.
Christina Choy +2 more
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Dianci bileiqi避雷器不仅在长期运行中因承受系统电压和偶然短时过电压而带来以阻性电流增大为主要特征的缓慢劣化过程，而且在重复雷击工况下存在因短时间内吸收较多的雷电能量而造成内部电阻片快速劣化过程，增大了避雷器发生热崩溃的风险。本研究提出避雷器劣化评价方法和判据，给出阈值为阻性电流增大1倍的缓慢劣化判据，以及在重复雷击过程增加短时间内累计吸收雷电能量阈值为达到通流容量30%的快速劣化判据，在此基础上，提出由缓慢劣化和快速劣化两种预警组成避雷器劣化预警方法以及相应的避雷器劣化预警装置 ...
王云龙 +4 more
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Dianci bileiqi, 2014 用MOV（氧化锌压敏电阻）的静态参数（压敏电压U1mA和漏电流IL）判定其劣化程度,只能直观反映压敏电阻的整体性能,而不能及时有效地的表征出压敏电阻的老化劣化趋势。根据MOV的U-I特性,结合肖特基势垒模型及离子迁移理论,提出MOV劣化过程中必然伴随着动态电阻Rd的变化。通过针对同一型号的MOV在不同脉冲电流下的大量实验分析得出:劣化前,8/20下Rd都呈"U"型分布,10/350下Rd呈缓慢递增后急速上升的趋势;劣化后,8/20下Rd没有明显变化,只有局部降低趋势而10/350下的Rd则出现不规则震荡。
徐乐 +4 more
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People and Nature, Volume 6, Issue 2, Page 792-799, April 2024.Abstract The ongoing degradation of Earth's ecosystems through human activities poses a severe threat to biodiversity. To mitigate this crisis, substantial changes in human behaviour are required. The frequency of nature experiences, particularly during childhood, has been established as a key predictor of actions that support biodiversity (hereafter ...
Yutaro Aota, Masashi Soga
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Untangling the threads of conservation: A closer look at restoration and preservation
Journal of Applied Ecology, Volume 61, Issue 2, Page 215-222, February 2024.Now that the Global Biodiversity Framework has just been set, there is a critical need to recognize their fundamental differences between the types of places that are priorities for preservation, restoration or both to make collective actions for achieving the targets and goals for nature and people.
Akira S. Mori, Forest Isbell
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