Results 11 to 20 of about 8,672 (112)
Dianci bileiqi, 2023 杆塔接地电阻超标大大增加输电线路雷害风险，进行基于冲击降阻效果的接地装置优化设计很有必要。研究发现在接地极上加装针刺短导体能够改善接地装置冲击特性，基于电磁场麦克斯韦微分方程建立了考虑土壤火花击穿特性的接地装置冲击特性有限元模型，然后分析了在水平接地极上添加针刺的降阻机制，最后基于有限元模型仿真研究针刺长度、数量和加装方式对冲击接地电阻的影响规律。结果发现，针刺长度和数量增加都能够降低冲击接地电阻，随针刺数量增多单根针刺降阻效率逐渐下降，添加单根针刺时采用单边竖直加装方式具有最好的降阻效果 ...
李景丽 +4 more
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Rare Metals, Volume 45, Issue 2, February 2026.ABSTRACT Ni3S2 has emerged as a promising catalyst for the electrochemical oxidation of biomass‐derived 5‐hydroxymethylfurfural (HMF) to 2,5‐furandicarboxylic acid (FDCA), driven by its distinctive physicochemical properties. However, its practical catalytic efficiency is severely hindered by abundant electrochemically inactive surface sites and poor ...
Cheng‐Feng Yi +5 more
wiley +1 more source
Jianzhu Gangjiegou Jinzhan, 2022 将黏滞阻尼器引入格构式拱形刚架，分析了阻尼器对结构平面内地震响应的控制效果。通过动力时程分析，研究了多遇地震作用下阻尼器减震效果随阻尼器布置位置、阻尼系数及结构关键参数取值的变化规律；揭示了罕遇地震作用下黏滞阻尼器对结构受力性能的改善机理。研究结果表明：在结构拱柱连接处附加黏滞阻尼器，其竖向减震效果较横向更显著；随阻尼系数的增加，位移减震率先上升后平缓甚至下降；罕遇地震作用时，在体系层面，黏滞阻尼器有效地降低了结构的整体变形；在构件层面，黏滞阻尼器改善了拱脚杆件塑性程度，使结构各构件受力更均匀。
贺拥军 +3 more
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Rare Metals, Volume 45, Issue 2, February 2026.ABSTRACT Internal oxidation has been identified as an effective method for enhancing the strength of AgMg alloys. However, the concurrent occurrence of embrittlement remains inadequately understood, thus limiting their broader application. This study investigates the oxidation behavior of AgMg alloys with Mg concentrations ranging from 1 at% to 7 at ...
Hai‐Cheng Zhu +12 more
wiley +1 more source
Dianci bileiqi, 2023 针对科研生产厂区独立接地系统难以长期有效降阻的问题，基于有限元理论建立了建筑独立接地系统的雷击暂态接地模型，基于该模型探究了有限面积下建筑独立接地装置的防雷降阻优化方法。研究结果显示，对于有限面积下安装的独立接地系统，采用接地网加装接地模块以及双地网加装垂直接地极的方式均有良好的降阻效果。在考虑造价经济性的前提下，使用双地网配合垂直接地极、且垂直接地极间距为10 m～20 m时有更好的降阻效果。研究结果对有限面积下建筑物独立接地系统的设计与优化具有一定的参考意义。
古维富 +4 more
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Oxidation Performance of NiCoCrAlYTa + 7YSZ Coatings With Ta Addition at Different Temperatures
Rare Metals, Volume 45, Issue 1, January 2026.ABSTRACT This study investigates the morphology and oxidation behavior of thermally grown oxides (TGO) formed at the interface of NiCoCrAlYTa + 7YSZ (7 wt% Y2O3‐stabilized zirconia) coatings deposited by air plasma spray (APS) in air environments at 1050°C, 1100°C, and 1150°C. The enrichment of Ta‐rich oxides beneath the TGO, along with the segregation
Cheng Xu +8 more
wiley +1 more source
Gaoya dianqi, 2013 降低变电站接地电阻,对保障人员、设备安全特别重要,敷设斜接地极是降低变电站接地电阻的重要措施。为确定斜接地极降阻效果,采用CDEGS软件建立仿真模型,分析了斜接地极布置位置、角度、长度、根数等对不同面积接地网的降阻效果和特征,进而确定了斜接地极的布置方式,并将斜接地极与垂直接地极进行对比。结果显示:敷设斜接地极能够有效降低变电站接地电阻,特别是对100 m×100 m以下地网降阻效果较好;均匀土壤中斜接地极降阻效果优于垂直接地极;分层土壤结构中,接地极的降阻效果取决于实际土壤结构 ...
刘渝根, 张竞, 田资
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Ultrasound in Obstetrics &Gynecology, Volume 66, Issue 5, Page 621-630, November 2025.ABSTRACT Objectives To compare the maternal hemodynamics of Chinese women at low and at high risk for preterm pre‐eclampsia (PE) and assess the differences in hemodynamic parameters between high‐risk women with or without prophylactic aspirin. Methods This was a prospective longitudinal case–control study of 857 Chinese women with a singleton pregnancy
X. Wang +11 more
wiley +1 more source
Dianci bileiqi, 2013 介绍了非金属接地模块的组成及降阻原理,通过冲击电流试验平台,在不同土壤电阻率下分别对不同大小、不同形状、不同材料的接地体进行冲击电流试验。分析试验数据结果表明,施加不同冲击电流时,相同散流面积下圆柱形接地模块的散流效果比长方体形的散流效果好,冲击电流越大效果越明显;随着接地模块体积和散流面积的增加,降阻效果的增加呈饱和趋势;接地模块的降阻率不随土壤电阻率的改变而改变,土壤电阻率越高,接地模块的降阻效果越好;石墨型接地模块的降阻效果堪比传统金属接地体,石墨部分降阻效果非常明显,为工程应用提供参考。
吴昊 +5 more
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Opportunities, research gaps, and risks in allogenic ecosystem engineer mimicry
Conservation Biology, Volume 39, Issue 4, August 2025.Abstract In an age of anthropogenically driven species loss and increasingly novel ecosystems, ecosystem engineer restoration is a process‐based approach to supporting ecosystem function. Many ecosystem engineers have low or declining population sizes.
Brandi Goss +2 more
wiley +1 more source