Results 11 to 20 of about 7,400 (110)
Jianzhu Gangjiegou Jinzhan, 2021 为了深入了解内置工字形CFRP型材的方钢管混凝土中长柱的力学性能,通过试验与有限元分析结合的方式研究了其在双向偏心状态下的工作机理及破坏形态。在此基础上,对典型构件进行了全过程分析,研究了偏心率、含钢率、长细比、钢材屈服强度以及混凝土抗压强度对构件受力性能的影响。研究结果表明,内置工字形CFRP型材的方钢管混凝土中长柱的荷载-挠度曲线可分为弹性阶段、弹塑性阶段、塑性强化阶段以及下降阶段4个阶段;CFRP型材与钢材及混凝土有着良好的协同工作性能,可加强对混凝土的约束作用,CFRP型材最终发生脆性破坏 ...
冯兴, 李帼昌, 杨志坚, 曹文正
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Rare Metals, Volume 45, Issue 1, January 2026.ABSTRACT Moist‐electric generators (MEGs) harness energy from ubiquitous ambient humidity, which has emerged as a promising way to collect energy irrespective of location and time. This study presents a high‐performance MEG employing a bilayer Janus nanofiber membrane: a hydrophilic layer (lithium chloride/citric acid/polyvinyl alcohol) for enhanced ...
Peng Chen +7 more
wiley +1 more source
Teshugang, 2021 铸坯高中心等轴晶率及小的二次枝晶臂间距有利于降低高碳钢M+E-EMS连铸坯中心偏析。通过建立GCr15钢220 mm×260 mm连铸坯耦合有限元-元胞自动机模型(CAFE)及二次枝晶臂间距(SDAS)模型,研究结晶器电磁搅拌、过热度和拉速对中心等轴晶率及二次枝晶臂间距的影响。结果表明,相比于拉速,过热度和结晶器电磁搅拌对其影响明显。随着过热度降低及结晶器电磁搅拌强度增加,铸坯中心等轴晶率增加而二次枝晶臂间距减小,而拉速对凝固终点和中心固相率影响大。工业试验结果表明,采用结晶器与凝固末端电磁搅拌 ...
左欢, 杨祝英, 安航航
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Finding floral and faunal species richness optima among active fire regimes
Conservation Biology, Volume 39, Issue 6, December 2025.Abstract Changing fire regimes have important implications for biodiversity and challenge traditional conservation approaches that rely on historical conditions as proxies for ecological integrity. This historical‐centric approach becomes increasingly tenuous under climate change, necessitating direct tests of environmental impacts on biodiversity.
Zachary L. Steel +8 more
wiley +1 more source
Infant Mental Health Journal: Infancy and Early Childhood, Volume 46, Issue 6, Page 870-885, November 2025.Abstract Profiles of parental reflective functioning (PRF) may offer valuable insights into individual differences in PRF. Previous studies have identified PRF profiles; however, further validation is needed. This study aimed to investigate the convergent validity of the identified PRF profiles by examining their association with a related measure of ...
Eva Back Madsen +6 more
wiley +1 more source
Jianzhu Gangjiegou Jinzhan, 2022 摩擦摆隔震技术具有隔震周期与上部建筑的自重无关、自带摩擦耗能能力、隔震层没有初始偏心等优点，正逐渐被我国工程界所接受。但是，由于摩擦摆支座的水平刚度与其所受竖向力成比例，上部结构在水平地震作用下产生的倾覆力矩会使摩擦摆支座的竖向力发生变化，从而导致隔震层刚度中心偏移并可能使隔震层发生扭转。以一个摩擦摆隔震原型建筑的地震反应分析为例，说明现行有关规范中采用的偏心率无法正确反映摩擦摆隔震层的扭转反应特性。通过推导上部结构倾覆力矩和摩擦摆隔震层偏心距之间的关系 ...
付皓然, 曲哲
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Ultrasound in Obstetrics &Gynecology, Volume 66, Issue 2, Page 135-146, August 2025.ABSTRACT Objective To derive pooled estimates of maternal, fetal and pediatric outcomes up to the age of 30 months in patients undergoing pre‐ or postnatal surgery for open spina bifida (OSB). Methods A systematic search was conducted in MEDLINE, PubMed (non‐MEDLINE records), Embase, Web of Science, ClinicalTrials.gov, Cochrane Central Register of ...
Y. Kunpalin +10 more
wiley +1 more source
Does donor country impact the efficacy of health aid?: Evidence from the COVID‐19 pandemic
World Medical &Health Policy, Volume 17, Issue 1, Page 31-48, March 2025.Abstract During the coronavirus disease 2019 (COVID‐19) pandemic, many nations relied on unprecedented amounts of health‐sector aid to efficiently vaccinate their populations. These vaccines and supporting materials came from a variety of traditional and nontraditional donors, with the majority donor differing by recipient country.
Anthony Un, Paul Un
wiley +1 more source
Shiyou jixie, 2014 偏心环是高造斜率井眼轨迹控制工具造斜的核心部分。精确控制内、外偏心环是高造斜率井眼轨迹控制工具轨迹控制精度高、井眼净化好等诸多优异性能的保证。为此，通过运用SolidWorks Motion动态模拟，对内、外偏心环的理想工作状态和实际工作状态分别进行仿真和对比分析，得到偏心环的实际运动轨迹和内偏心环啮合尺寸的内在联系，指出开孔直径与螺栓直径的差值应该大于整个偏心机构的偏心距才不会干涉，从而选择出高造斜率井眼轨迹控制工具最佳的内偏心环驱动啮合尺寸 ...
张红 +6 more
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Guangtongxin yanjiu, 1990 本文研究了多包层单模光纤的双折射特性,分析了光纤椭圆偏心率及剖面形状对双折射和群时延差的影响。计算结果表明,改变光纤偏心率或选择适当的工作频率及剖面形状可获得低双折射或高双折射的保偏单模光纤。
徐明刚
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