Results 31 to 40 of about 8,113 (174)
采用4种不同纵磁触头结构的126kV单断口真空断路器温升性能对比研究
Gaoya dianqi, 2021 为进一步提升126 kV单断口真空断路器额定通流能力,文中针对4种采用不同纵磁触头结构的126 kV真空断路器的温升特性通过仿真进行了对比研究。4种纵磁触头分别为2/3、3/4匝线圈型、马蹄铁型和开槽马蹄铁型纵磁触头。有限元仿真结果表明在通流3 150 A时4种触头的热态交流电阻分别为30.2、36.9、24.0、16.3μΩ。4种断路器整机的温度分布采用有限体积法计算得到,温升仿真模型由通流2 500 A下的实验结果验证。结果表明,仿真模型在灭弧室周围的5个测温点内计算误差小于10 ...
马朝阳 +6 more
doaj
ImpactsAnalysis of Climate Change on China’s Marine Economy Based on CGE Model [PDF]
, 2015 近10年来，海洋经济已经成为中国国民经济新的增长点，对拉动全国经济发展起着重要的作用。然而海洋经济活动主要分布的海岸带地区却是生态环境最为脆弱的区域，特别是在全球气候变化的背景下，这种脆弱性愈发明显。与此同时，为减缓气候变化而实施的碳减排政策对中国经济增长（包括海洋经济增长）带来严峻的压力。在此双重背景下，综合地评估不同气候变化情景下的主要关键风险、以及实施和不实施减排政策对中国海洋经济的影响，可以为应对气候变化、促进海洋经济发展的战略和政策的制定提供科学依据，因而具有十分重要的现实意义和理论意义 ...
孔昊
core
Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT MCrAlX coatings are widely used as bond coats in thermal barrier coating systems to protect turbine blades from high‐temperature oxidation. However, their oxidation resistance is often restricted by uncontrolled microstructures, surface roughness, and aggregation of reactive elements (REs). In this study, high‐repetition‐rate femtosecond laser
Wei Qian +7 more
wiley +1 more source
Gaoya dianqi, 2015 传统交流温升试验电源系统采用电网直接供电,因此只能进行50 Hz温升试验,而无法实施60 Hz温升试验,同时,由于其自动化程度较低,在电网电压波动以及负载随温度变化的情况下,只能通过现场手动调节调压器实现电流的稳定控制,且缺乏有效的远程监控手段,不利于系统运行的综合管理。为解决上述问题,笔者结合温升试验的工艺要求以及试验室的具体试验条件,采用发电机作为温升试验电源,通过调节变频器的输出频率改变拖动电动机的转速,实现了试品对不同试验频率的需求;采用可编程控制器设计了一套温升试验自动控制系统 ...
贾一凡 +6 more
doaj
Nitrogen Transports and Transformations in Mangrove Sediments using Nitrogen Isotope Techniques in China [PDF]
, 2012 人类活动对生态系统的影响日益扩大，过量施肥、化石燃料的燃烧等引发的氮(N)负荷迅速增加。陆地生态系统过剩的N通过流域汇集至河口和海岸，威胁着海洋生态系统的健康。目前，全球N循环正致力于揭示河口和海岸地区N的源汇格局及主导机制。红树林湿地广泛分布于热带、亚热带河口和海岸地区，作为陆源营养盐入海过渡带，在缓解陆源N输入方面扮演着重要角色，成为了研究的热点。 本研究利用N稳定同位素技术，将现场培养与室内模拟培养相结合，揭示了我国东南沿海典型河口和海湾红树林湿地沉积物总氮沉积、固氮作用、反硝化作用 ...
李颖
core
Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT Aqueous vanadium dioxide (VO2)‐based smart thermal insulation coatings represent a viable strategy to decrease building energy consumption and advance sustainable development goals. However, the inherent instability and limited compatibility with polymer matrices of VO2 hinder its widespread application.
Xiuxian Zhao +9 more
wiley +1 more source
Finite element simulation of the temperature curve of wire rods during the whole process of rolling [PDF]
, 2016 The temperature distribution of billets in a heating furnace is simulated by Deform software and is verified by the "black box". When the heating time is 70 min the temperature difference between surface and center is about 66℃, but it reduces to 15 ...
DENG Su-huai +5 more
core +1 more source
Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT Emerging as attractive alternatives for sustainable, low‐cost, and high‐performance electromagnetic interference (EMI) shielding, biomass‐derived carbon is nonetheless constrained by a limited repertoire of shielding mechanisms. Herein, a straightforward method was employed to synthesize self‐supporting Co nanoparticles embedded in porous N ...
Yingjie Xu +6 more
wiley +1 more source
Gaoya dianqi, 2018 为综合分析特高压直流输电用干式平波电抗器的损耗与温升,获得其热点位置与热点温升,文中推导了平波电抗器各个包封中直流电流损耗与谐波电流损耗分布的计算方法。针对一台±800 kV/4 000 A特高压干式平波电抗器,分析了加载等效直流电流的温升试验工况下电抗器的损耗分布与实际运行中包含谐波损耗的损耗分布的差异。对温升试验工况下特高压干式平波电抗器的温度场进行了计算,获得其温升分布,通过相应的温升试验,验证了仿真计算结果的可靠性;最后,比较了运行工况与温升试验工况下特高压干式平波电抗器的温升分布的差异 ...
肖彩霞, 李琳, 纪锋, 高冲
doaj
Æ E Æ Å – Reshaping the Role of Træna Fishermen
, 2022 This diploma project aims to strengthen the viability of Træna’s community by proposing an ocean research facility in the archipelago, enabling the next generation of local fishermen to collect oceanographic data while working at sea. The idea of the fisherman as oceanographer is inextricably linked to the architectural program on the island of ...
openaire +1 more source