Results 21 to 30 of about 801 (117)
, 2019 高压变压器、电抗器等油浸式电力设备广泛应用于电网中，设备的故障诊断及状态判断至关重要。为了及时准确地诊断出油浸式电气设备的潜伏性故障。分析油浸式电力设备发生过热、放电等内部故障产生的气体成分，找出不同故障类型的特征气体。提出设备故障警戒这一概念,应用三比值法建立的特征气体与故障状态一一对应关系作为判据做出故障判断。给出了应用油色谱分析故障的案例。结果表明油色谱分析对油浸式电力设备的潜伏性故障诊断具有技术可行性和广阔的应用前景。
典强 安
core +2 more sources
Urban sustainability commitment: Actor constellations and motivations
Review of Policy Research, Volume 43, Issue 1, January 2026.Abstract In recent years, cities have increasingly committed to sustainable urban development, despite it being a voluntary task. This paper investigates the causes behind this commitment by focusing on local policy‐makers and their motivation rather than viewing cities as unitary actors.
Svenja Katharina Schwarz +1 more
wiley +1 more source
Review of Policy Research, Volume 43, Issue 1, January 2026.ABSTRACT This article examines how the climate and energy policy in Finland changed between the two parliamentary terms of 2015–2019 and 2019–2023, when the EU tightened its greenhouse gas emission targets. We analyze the relevant policy measures (N = 223) of five government strategic plans and evaluate their stringency, i.e., their compulsory and ...
Markku Juha Kinnunen
wiley +1 more source
陆相湖盆细粒岩油气的概念、特征及勘探意义:以渤海湾盆地沧东凹陷孔二段为例
, 2018 陆相湖盆致密油气与传统致密油气和页岩油气有相关性，也体现出较大的差异性.通过对渤海湾盆地沧东凹陷孔店组二段（孔二段）优质'生油岩'开展岩性、物性、生烃特性、含油性、脆性综合分析及勘探实践，发现了一种赋存于陆相湖盆细粒沉积岩（粒径小于62.5 μm）之中的油气，并提出了细粒岩油气的概念.细粒岩油气不同于传统的致密油气和页岩油气，具有以细粒沉积为主，主要发育碳酸盐岩、细粒长英沉积岩、细粒混合沉积岩3种岩类；纵向上表现为纹层状或块状沉积，平面上稳定分布；3种岩性均具备良好的生烃条件，均具有一定的储集空间 ...
周立宏 +13 more
semanticscholar +1 more source
Ultrasound in Obstetrics &Gynecology, Volume 66, Issue 6, Page 706-715, December 2025.ABSTRACT Objective To evaluate the use of twin vs singleton growth charts for detecting small‐for‐gestational‐age (SGA) twins at risk of adverse neonatal outcomes. Methods MEDLINE, EMBASE, CINAHL, Cochrane and Scopus databases were searched electronically from inception to May 2024.
S. Sorrenti +9 more
wiley +1 more source
Functional Ecology, Volume 39, Issue 12, Page 3504-3516, December 2025.Read the free Plain Language Summary for this article on the Journal blog. Abstract Nitrogen (N) deposition strongly affects litter decomposition and nutrient release, thereby reshaping carbon cycling in terrestrial ecosystems. Although most studies have focused on above‐ground litter, the effects of N addition on fine root decomposition and their ...
Yuneng Wang +5 more
wiley +1 more source
Gaoya dianqi, 2012 准确预测变压器油中溶解故障特征气体的体积分数对发现变压器早期潜伏性故障,实现电力系统安全经济运行具有重要意义。将灰色多变量预测方法和马尔可夫链理论有机结合,提出了一种适合变压器故障特征气体体积分数预测的灰色马尔可夫组合预测模型。利用优化的背景值构造公式建立灰色多变量模型对变压器故障特征气体时间序列的宏观发展规律进行动态预测,在此基础上,建立故障特征气体时间序列的状态转移概率矩阵,以归一化的各阶自相关系数作为权重值,通过加权马尔可夫链模型修正灰色多变量模型预测值,实现变压器故障特征气体体积分数的预测 ...
毛自娟
doaj
Gaoya dianqi, 2021 SF6因其性能优异而广泛应用于电力工业,当电气设备出现放电故障或过热故障时,SF6气体将不可避免地发生分解。研究SF6分解机理,掌握SF6分解特性,以期提高设备的运维水平。文中从SF6分子解离、特征产物生成路径等方面,总结了SF6气体放电分解机理的相关研究进展,鉴于定性检测方法的局限性,指出结合DFT、ReaxFF等研究方法可厘清SF6的复杂分解过程;重点介绍了开展气体分解特性研究的基本测量与分析方法,包括:气相色谱质谱法、红外吸收光谱法及气敏传感器法等,其中气敏传感器因具备小型化、强响应等优势 ...
石磊 +9 more
doaj
, 2017 河流是连接大陆和海洋两大碳库的桥梁，在全球碳循环中的作用举足轻重.金沙江作为长江的上游段，对区域碳循环及区域化学风化的影响非常重要.于2015年8月8-18日对金沙江下游水-气界面CO2与CH4通量特征进行监测与分析.采用顶空平衡法结合薄边界层模型估算法计算表层水体CO2与CH4的分压以及水-气界面的交换通量，并分析环境变量与其之间的相关性.研究发现，金沙江下游表层水体p（CO2）平均值为2724.84±477.18 μatm，表层水体p（CH4）平均值为59.96±6.74 μatm；水 ...
秦宇 +9 more
semanticscholar +1 more source
Rare Metals, Volume 44, Issue 11, Page 8161-8197, November 2025.Graphical abstract AbstractThe studies on the synthesis of two‐dimensional (2D) Janus materials have made significant progress over the years. They offer new opportunities to increase the potential usage of Janus transition metal dichalcogenide (TMDC) materials in different application areas due to their unique structural, electrical, optical and ...
Ayça Coşkun +9 more
wiley +1 more source