Results 21 to 30 of about 13,145 (215)
Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT In conventional piezoceramics, the coordinated change between the dielectric constant (εr) and the piezoelectric charge constant (d33) usually limits the piezoelectric voltage constant g33 (g33 = d33/εr), a critical figure of merit for piezoelectric sensors.
Xiaoying Feng +7 more
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Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT Efficient and durable bifunctional electrocatalysts are vital for scalable water electrolysis. Here, we realize cobalt‐vacancy (Covac) engineering in CoFeP supported on N,P‐codoped carbon nanocages (Co1‐vacFeP/NPC) through a simple route comprising a CoFe Prussian blue analog precursor, phosphidation–pyrolysis, tannic‐acid etching, and a ...
Yuan‐Liang Yuan +6 more
wiley +1 more source
Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT The development of efficient and stable bifunctional catalysts remains a key challenge for green hydrogen production via electrochemical water splitting. In this study, a bimetallic Mo/Fe‐doped CoP2 nanoleaf array anchored on carbon cloth (Mo, Fe‐CoP2@CC) was synthesized from zeolitic imidazolate framework‐L (ZIF‐L) via an ion‐exchange and low‐
Xiangqun Zeng +6 more
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Gaoya dianqi, 2010 电力系统中出现的波形、幅值及持续时间各异的多种过电压对电气设备绝缘构成了严重威胁。鉴于电力系统过电压波形包含了丰富的电力系统工作状况和状态信息,笔者重点对电力系统过电压波形进行了分析,将从变电站过电压在线监测系统获取的雷电感应过电压、投电容器组过电压、合空载线路过电压、投切空载变压器过电压、弧光接地过电压、不对称接地短路共7种典型过电压波形作为对象,分析其主要特征,并通过小波变换,使含有高频分量的过电压特征在时频域得到更好的体现,为过电压特征提取及类型识别奠定基础。
郭良峰 +5 more
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, 2003 基于20 世纪60 年代 Halanay 和 Hale 关于微分系统平均性的思想 ,利用移动均值方法 ,研究了一类非线性具周期时滞系统的移动均值 ,利用移动均值方法和分区间分析方法证明了该类系统的平均化定理 ,得到了该类系统及其平均化系统解的渐近性行为.本文的分区间分析方法及 定理与以往研究的不同之处在于考虑了平均化系统中的时滞项.最后将结论应用到一个具有周期激励的时滞系统模型 ———非同期合闸产生的过电压模型 ,研究了该类系统在周期扰动和反馈控制下的稳定性问题 ,验证了本文所得结果 ...
史平(南京财经大学基础教学部) +3 more
core
Effect of Hydrogen Production System on Sub-Synchronous Oscillation Characteristics of Doubly Fed Induction Generator Systems With Series Compensation [PDF]
ObjectivesThe grid-connected operation of large-scale wind turbines increases the risks of sub-synchronous oscillation (SSO) in power systems, to address these issues, this study conducts an in-depth analysis of the effect of hydrogen production systems ...
LIU Zenan, LU Yanan, XU Tao
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Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT High‐power piezoelectric ceramics which have a wide operating temperature range are essential for sensor and actuator applications in extreme conditions. However, their development is fundamentally hindered by the inherent trade‐off among key parameters (TC, d33, Qm).
Rui Yan +10 more
wiley +1 more source
High Voltage Crossing Strategy of Wind Farm Considering Active and Reactive Coordinated Recovery [PDF]
ObjectivesTo address the serious high voltage ride-through (HVRT) problem faced by wind farms as a result of the large voltage surge at the grid-connected point after a DC fault, a recovery mechanism of “active priority balancing - reactive power dynamic
HAN Lu +4 more
core +1 more source
Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT The realization of bifunctional perovskite devices integrating photovoltaic (PV) and light‐emitting diode (LED) capabilities requires precisely controlled grain architectures to facilitate dual carrier transport pathways. In this work, sulfaguanidine (SG) molecules were introduced into the perovskite solution to reconstruct the crystallization
Jiong Li +7 more
wiley +1 more source
Gaoya dianqi, 2019 变压器空载合闸过程中由于电磁振荡产生过电压,若系统中存在高压电缆,电缆内部过电压耦合到电缆护层造成护层上电压较高,护层过电压与电缆布置方式和护层接地方式有关。文中针对白莲河抽水蓄能电站主变空载合闸时,电缆端部有异常放电声,并可见放电火花的现象,对主变空载合闸时系统产生的过电压进行测量,并对放电现象进行观测;同时采用ATP/EMTP软件计算空载合闸过电压耦合到电缆护层上的过电压大小。测量结果表明:空载合闸时主变侧过电压值并不大,进而计算得到放电处护层过电压最大值为21.49 kV,频率在600 kHz以内,
张才军 +6 more
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