Results 21 to 30 of about 18,581 (123)
Dianci bileiqi, 2020 以高纯石墨作为主要导电材料的柔性石墨接地体,因具有价格低廉、便于运输、电阻率低、耐腐蚀性好等诸多优点,而被电力、通信、石油化工、铁道、建筑等场所用于防雷接地网,并逐步推广使用。对4种典型结构的柔性石墨接地体在不同电流幅值下的交/直流体积电阻进行了测量,试验结果表明:柔性石墨接地体的连接金具的材料以及连接金具与柔性石墨接地体的连接方式对其体积电阻值有较大影响;柔性石墨接地体的电阻率低于6×10-5Ω·m;当施加的测量电流幅值足够大时,柔性石墨接地体的交/直流体积电阻的测量值趋于恒定。
桑建平 +5 more
doaj
Rare Metals, Volume 45, Issue 10, October 2026.ABSTRACT Carbides strengthen the grain boundaries; nevertheless, excessive carbide precipitates embrittle the grain boundaries of high‐temperature alloys during prolonged service. Here, we provide direct evidence of solute rare‐earth atoms and demonstrate that they can trap vacancies and inhibit interstitial diffusion, restraining carbide precipitation
Jiali Zhang +10 more
wiley +1 more source
Dianci bileiqi, 2017 利用CDEGS仿真计算了典型杆塔接地网的接地电阻,首先对比了柔性石墨接地体与圆钢、锰铜在工频接地及冲击接地性能的区别,结果表明,柔性石墨接地体的工频接地电阻略高于圆钢,但由于其非磁性,较弱的趋肤效应使其冲击接地电阻低于圆钢,因此,柔性石墨接地体具有良好的防雷接地特性。然后,以广东佛山典型输电线路中柔性石墨接地体示范应用工程为例,介绍了有关柔性石墨接地体的实际工程施工工艺及技术,为其他类似的工程及试验提供参考依据。
詹清华 +5 more
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Dianci bileiqi, 2020 目前在输电线路杆塔接地网中应用广泛的接地材料包括镀锌扁钢、锰铜等传统金属材料,但在高频电流条件下传统金属接地体存在明显的集肤效应,进而影响其散流特性,新兴的非金属石墨复合接地材料因其"导电不导磁"的特性有效改善了上述问题。针对石墨复合接地体的结构进行优化进而制备了扩径石墨复合接地体,利用有限元仿真分析其集肤效应,并采用CDEGS软件仿真分析传统金属接地体、实心石墨复合接地体及扩径石墨复合接地体在不同频率、不同土壤情况、不同直径条件下的散流特性。研究结果表明,在高频高阻条件下 ...
李文琦 +5 more
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Scientists’ warning on the global destruction of rock outcrop ecosystems
Conservation Biology, Volume 40, Issue 5, October 2026.Abstract Rock outcrops are geological formations that harbor a highly specialized biota adapted to harsh environmental conditions that differ from their surrounding landscapes. They are globally distributed, especially in old, highly weathered landscapes, and can function as habitat islands containing high levels of endemism and distinct evolutionary ...
Luiza F. A. de Paula +19 more
wiley +1 more source
Canine Distemper Virus Research in China and Future Directions for Conservation 中国犬瘟热病毒研究现状与保护策略展望
Integrative Conservation, Volume 5, Issue 3, Page 268-280, September 2026.ABSTRACT Canine distemper is a highly contagious, severe disease caused by the canine distemper virus (CDV). With a worldwide distribution and ever‐expanding list of susceptible hosts, CDV poses a growing risk for many threatened wildlife species, both in captivity and their native habitats. As a megadiverse country, China is home to myriad endemic and
Aliana C. Norris +4 more
wiley +1 more source
Journal of Adolescent &Adult Literacy, Volume 70, Issue 2, September/October 2026.ABSTRACT Despite being one of the largest immigrant groups in the United States (U.S.), Asian heritage youth are often essentialized by dominant literacy ideologies as quiet, obedient, or culturally foreign, leaving their identity negotiation underexamined and insufficiently supported.
Zixin Chen, Anqi Zu, Betina Hsieh
wiley +1 more source
Dianci bileiqi, 2017 针对易腐蚀地区中金属接地体存在的易腐蚀问题,提出了耐腐蚀能力强的柔性石墨接地材料。对柔性石墨复合接地材料本体进行了耐腐蚀能力试验,试验结果表明,柔性石墨接地体腐蚀速率远低于铜与钢,具有很强的耐腐蚀性能。然后对柔性石墨接地体接头进行了加速腐蚀试验,试验结果表明,接头会发生剧烈的电化学反应,是柔性石墨接地体防腐的重点。为了解决接头防腐问题,提出采用防腐石墨布的方法。最后介绍了柔性石墨接地体在易腐蚀地区中的示范应用工程。
李恒真 +5 more
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Dianci bileiqi, 2023 山区输电线路杆塔所处位置通常土壤电阻率高且空间有限，故散流效果差，降阻比较困难。针对这些问题，本研究使用CDEGS软件设计了立体均压环结构接地体，在不同激励电流类型、土壤电阻率、接地体深度和水平射线长度情况下，进行了冲击特性的分析。仿真结果表明：在工频电流和雷电流作用下，该接地体都能够具有良好的均压和散流效果。相同土壤电阻率下，立体均压环接地体冲击接地电阻比传统圆环形接地体冲击接地电阻至少可较低8.9%,最大跨步电压至少可降低16.0%,在高土壤电阻率下，降低幅度增大 ...
周西杰 +4 more
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The Evolution of Metal Halide Perovskite Transistors
Rare Metals, Volume 45, Issue 9, September 2026.ABSTRACT Metal halide perovskites (MHPs) offer a revolutionary pathway for next‐generation field‐effect transistors (FETs) because of their exceptional carrier mobilities and cost‐effective processability. However, their transition to practical electronics is significantly challenged by intrinsic instability and imbalanced charge transport. This review
Jiangnan Xia +8 more
wiley +1 more source