Results 21 to 30 of about 392,713 (166)

Encapsulation of Bi2S3 Within Multifunctional Sulfurized Polyacrylonitrile Matrix Enables High‐Performance Wide‐Temperature Sodium/Potassium‐Ion Batteries Through Solid–Solid Conversion

open access: yesRare Metals, Volume 45, Issue 6, June 2026.
ABSTRACT With high theoretical capacity and low cost, bismuth sulfide (Bi2S3) demonstrates considerable potential as an anode for sodium/potassium‐ion batteries (SIBs/PIBs). Unfortunately, significant volume variation, low electrical conductivity, and dissolution of polysulfides drastically weaken their intrinsic merits.
Fuyu Xiao   +11 more
wiley   +1 more source

永磁直驱风机通过MMC-HVDC并网的故障穿越策略

open access: yesGaoya dianqi, 2017
当受端交流电网发生严重短路故障,经柔性直流并网的风电场必须降低出力,使直流输电系统的直流电压保持在安全范围内。针对永磁直驱风机经MMC-HVDC并网系统,提出一种提升其故障穿越能力的控制策略。该策略结合降低风电场交流电压和降低风机输出有功电流2种方式,可以实现风电场侧有功功率的快速降低。同时,为了在故障时限制永磁直驱风机直流链电压的增长,在风机中引入直流电压偏差控制。仿真结果表明:主网发生对称和不对称故障时,MMC直流电压和永磁同步风机直流链电压均可维持稳定,系统可以实现故障穿越。
于洋, 徐谦, 杨升峰, 徐政
doaj  

Atomically Dispersed Platinum Sites Immobilized on NiFe LDH by Controlling Localized Amorphization for Efficient Alkaline Electrocatalytic Hydrogen Evolution

open access: yesRare Metals, Volume 45, Issue 6, June 2026.
ABSTRACT Platinum (Pt) single‐atom catalyst (SAC) shows great promise for hydrogen evolution reaction (HER), but faces a huge challenge in activity enhancement due to the isolated single‐atom sites. Fabricating support with partially amorphous (pa) structures to realize the synergetic interaction in neighboring single atoms could facilitate H2O ...
Yanhui Song   +9 more
wiley   +1 more source

高压开关电动操动机构的电气制动技术

open access: yesGaoya dianqi, 2017
高压开关电动操动机构的电气制动技术虽然是一项重要的应用技术,但是未得到足够的重视。因此,文中系统阐述了电气制动技术的工作原理及其技术特点,总结了工程应用中出现的常见问题与排查方法,利用Lab VIEW软件对样机的制动参数进行了测试。经分析得出:采用能耗制动,将电动机变为他励发电机,产生的制动能量使电动机构在0.3 s以内完成停车。根据电机回路电源类别选择不同的制动方式:永磁直流电动机为直流电源时,采用单电阻制动方式;串励电动机为单相交流电源,采用双电阻制动方式。在相同的制动回路中 ...
陈旭   +6 more
doaj  

Boosting Thermoelectric Properties of BiSbSe3 Through Ag‐Induced Interstitial Occupancy and Multi‐Phase Microstructure

open access: yesRare Metals, Volume 45, Issue 6, June 2026.
ABSTRACT Te‐free BiSbSe3 is a promising medium‐temperature thermoelectric (TE) material owing to its cost‐effectiveness and intrinsically low lattice thermal conductivity. However, its comparatively low electrical conductivity has severely hindered the optimization of TE performance.
Xiaowei Shi   +10 more
wiley   +1 more source

高压断路器直线电机操动机构的动态特性分析

open access: yesGaoya dianqi, 2009
研究了一种高压断路器直线电机操动机构,设计分析了永磁直线直流电机及其运动特性。基于40.5 kV真空断路器机械特性的要求,设计了一台配有制动保持装置的永磁直线直流电机操动机构,利用有限元方法建立了电机的仿真模型,对永磁直线直流电机的基本特性和起动过程进行了特性仿真,得到了电机运行时的电磁推力、电流、速度等曲线并进行了分析,得出了电机操动机构能够提供的机械特性,为真空断路器采用直线电机操动机构提供了依据。
林莘, 李永祥, 徐建源, 吴刚
doaj  

Upcycling of Waste Polyethylene Terephthalate Plastics to Fabricate Cobalt–Nickel Metal–Organic Frameworks and Their Phosphides for Efficient Oxygen Evolution Reaction

open access: yesRare Metals, Volume 45, Issue 6, June 2026.
ABSTRACT The urgent environmental crisis caused by polyethylene terephthalate (PET) waste necessitates efficient upcycling strategies. Herein, we establish a novel pathway to transform waste PET plastic into a high‐performance catalytic material for mediating the oxygen evolution reaction (OER). Through a one‐step hydrothermal process, waste PET serves
Xin Wang   +5 more
wiley   +1 more source

500 kV耦合负压换流型混合式直流断路器原理与研制 [PDF]

open access: yes全球能源互联网, 2018
多端柔性直流系统在分布式能源和直流负荷接入、网络柔性互联、电能质量等方面具有显著优势,成为未来电网的重要发展趋势。为了保证多端柔性直流系统安全稳定可靠运行,需要能够在数毫秒内开断故障电流的直流断路器。本文面向张北±500 kV柔性直流电网示范工程的应用需求,开展了500 kV直流断路器原理研究与样机研制。首先,提出500 kV耦合负压换流型混合式直流断路器系统方案,给出其拓扑结构、工作原理和控制逻辑;进而,设计基于电磁斥力操动机构和电磁缓冲机构的快速机械开关 ...
张翔宇   +7 more
doaj   +1 more source

Structural Distortion for Polyoxometalate‐Derived Metal Sulfide Induced by In Situ Intercalation With Organic Ligands Achieving Efficient Electrocatalytic Hydrogen Evolution Performance in Alkaline/Seawater Medium

open access: yesRare Metals, Volume 45, Issue 6, June 2026.
ABSTRACT The electrocatalytic water splitting technique was widely taken for hydrogen evolution, due to its cost‐effectiveness and environmental friendliness. The design of electrode material as electrocatalysts play a key role in achieving high efficiency.
Yaling Zhu   +5 more
wiley   +1 more source

Changing trends in prenatal screening and treatment of cytomegalovirus infection in France: 7‐year national cohort study (2017–2023)

open access: yesUltrasound in Obstetrics &Gynecology, Volume 67, Issue 6, Page 756-763, June 2026.
ABSTRACT Objectives Cytomegalovirus (CMV) is the leading cause of congenital infectious neurosensory impairment. We aimed to present national epidemiological data on maternal CMV infection during pregnancy in France, focusing in particular on primary infection in the periconceptional period or first trimester, and to assess the impact of changes in ...
P. Coste‐Mazeau   +176 more
wiley   +1 more source

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