Results 11 to 20 of about 954,672 (163)
Gaoya dianqi, 2018 变压器热点温度是直接影响变压器绝缘老化速度及决定变压器运行状态的重要因素之一。文中综述了近年来国内外变压器热点温度研究方法的发展历史及现状。文中主要对基于测温系统的热点温度监测,基于经验公式、热路模型或数值计算方法的热点温度计算及基于人工智能学习算法的热点温度预测三大类方法进行了归纳总结,对比了各类方法优缺点,并论述了三类方法今后的研究、发展方向。
廖才波 +6 more
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Gaoya dianqi, 2022 在直流输电系统中晶闸管换流阀存在发生火灾的风险。文中联合热失重分析—差式扫描量热仪（TGA/DSC）以及热空气炉的实验方法，研究了换流阀主要元件的有机高分子材料在空气环境下的热失重起始温度、放热临界温度以及燃点。提出了通过TGA/DSC联用实验测定换流阀高分子材料在空气环境下的燃点的方法。通过对实验确定的3项参数之间的关联性分析，确定了影响换流阀元件高分子材料的引燃温度的影响因素。研究结果表明：换流阀的引燃过程受到了高分子材料的热解过程和在高温下的放热过程的共同作用 ...
朱正一 +6 more
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The Structural Origin of the Amorphous‐to‐Crystalline Transformation in Cu‐Zr Based Amorphous Alloy
Rare Metals, Volume 45, Issue 5, May 2026.ABSTRACT Amorphous alloys (AAs) possess a metastable structure from a thermodynamic perspective and tend to crystallize under external conditions, which in turn alters their material properties. To gain an in‐depth understanding of their crystallization mechanism, this study employed in situ spherical aberration‐corrected transmission electron ...
Yajie Huang +4 more
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Gaoya dianqi, 2018 文中提出了一种基于改进支持向量机的变压器实时热点温度预测方法。该方法以变压器负载电流、环境温度和顶层油温为特征值,将变压器热点温度预警与预测相结合,目的在于实现基于近期历史运行数据的变压器实时热点温度预测。文中研究分析了基于改进网格搜索、遗传算法及粒子群算法的支持向量机在变压器短期热点温度预测中的应用效果,结果表明,3种改进方法均可有效提升预测精度,但基于改进网格搜索算法的支持向量机预测效率最高。最后,以某35 k V油浸式变压器实时热点温度数据为样本集,文中所述方法可有效实现变压器短期热点温度预警预测,
廖才波 +5 more
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Rare Metals, Volume 45, Issue 5, May 2026.ABSTRACT Layered double hydroxides (LDHs) are attractive non‐noble catalysts for overall water splitting (OWS), yet their hydrogen evolution reaction (HER) activity is often limited by suboptimal *H adsorption and a paucity of accessible sites. Herein, we introduce an oxygen‐vacancy (Ov) engineering strategy to construct ultrathin Ni‐Fe LDH nanosheets ...
Qi Liu +8 more
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Rare Metals, Volume 45, Issue 4, April 2026.ABSTRACT Thermally driven hydrogenation of CO2 to light olefins (C2=–C4=) using metal oxide‐zeolite tandem catalysts is an effective strategy for achieving carbon neutrality. However, progress in this area is constrained by zeolite pore transport limitations, acid‐site inactivation, and surface carbon poisoning.
Haifeng Tian +10 more
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Success of restoration strategies in preventing extirpation of 2 critically endangered coral species
Conservation Biology, Volume 40, Issue 2, April 2026.Abstract An unprecedented marine heatwave in 2023 caused widespread coral bleaching and mortality throughout the Caribbean. In the Florida Keys (USA), 2 foundation species, elkhorn coral (Acropora palmata) and staghorn coral (Acropora cervicornis), were severely affected.
Erinn M. Muller +29 more
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Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT Cost‐effective and efficient non‐noble‐metal catalysts for selective lignin hydrogenolysis remain elusive, representing a significant challenge in biorefinery. Here, we prepared a nitrogen‐doped carbon supported CoNi bimetallic catalyst, which was successfully derived from zeolitic imidazolate framework (ZIF) via high‐temperature pyrolysis ...
Xingwei Luo +3 more
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Gaoya dianqi, 2017 为了研究红外成像技术在GIS内局部过热故障诊断的有效性和可行性,文中通过静态试验方法,搭建了GIS内局部过热故障仿真平台,研究了故障点不同温度下外壳不同位置的稳定温升,并得到了GIS内部过热点温度及与其对应外壳温升间的函数关系。利用红外成像仪可清晰观察到外壳的局部高温,验证了试验的有效性和可行性。研究表明:当GIS内部发生过热故障时,在与其对应的外壳顶部将产生局部高温。以此高温点为中心,沿GIS轴线方向温度向两侧递减,呈开口向下的抛物线形。距最高温度点0.6 m处,温度变化大约为1115℃。超过0.6 ...
李爽 +6 more
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Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT Single‐atom catalysis hinges on fundamental challenges in precisely controlling metal‐support interactions and rationally regulating metal–adsorbate relationships. Herein, we report a universal strategy for constructing highly efficient and well‐defined Cu(I) single‐atom catalysts based on a trifurcate AlL3 molecular support.
Donghui Zhang +9 more
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