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疲劳荷载特性对8.8级M24高强度螺栓疲劳裂纹扩展机理影响探析
Jianzhu Gangjiegou Jinzhan, 2023 为研究常幅疲劳荷载特性对高强度螺栓疲劳裂纹扩展的影响，针对钢结构端板连接用8.8级M24高强度螺栓在不同应力比/应力幅作用下常幅疲劳试验所得到的24个试件断口形貌进行定量分析，并采用ABAQUS软件数值模拟高强度螺栓应力集中情况，探讨含初始裂纹高强度螺栓裂纹尖端应力强度因子与荷载特性、预制裂纹形状之间的关系。结果表明：在轴向受拉疲劳荷载作用下，螺母与螺栓啮合第1圈螺纹处为疲劳断裂最不利位置；试件断口稳定扩展区面积与应力比/应力幅呈负相关，快速扩展区面积与应力比/应力幅呈正相关 ...
樊丽轩 +4 more
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Dianci bileiqi, 2020 针对三维裂纹尖端应力强度因子计算困难的现状,提出了一种新型的三维裂纹应力强度因子计算方法,通过与其它方法在计算含圆孔平板裂纹尖端应力强度因子的对比分析,验证了本文应力强度因子计算方法的有效性和优越性。建立含裂纹缺陷的高压断路器瓷套有限元数值模型,将本文方法应用于高压断路器瓷套裂纹的应力强度因子计算,研究了高压断路器瓷套表面裂纹应力强度因子与瓷套所处环境温度、裂纹分布位置和裂纹尺寸的变化关系,获得了易导致瓷套断裂的环境、裂纹分布位置和裂纹尺寸,为电力行业中断路器瓷套的设计及运行维护提供有效的技术指导和借鉴。
赵滨滨, 王莹, 徐晓萌, 崔文婷
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Shuitu Baochi Xuebao, 2023 粗糙度是影响坡面流水动力特性的关键因子,为探究渐变粗糙度影响下坡面流水力特性,采用粒子图像测速技术(particle image velocimetry, PIV)观测并分析3组流量下渐变粗糙床面下坡面流的流速轮廓线、紊动强度、雷诺应力和壁面切应力的变化规律。结果表明:(1)流速随粗糙度增加而减小;拟合无量纲流速得到流速分布对数公式,粗糙度增大与拟合常数A成反比,与积分系数B成正比。(2)渐变地表粗糙度流向紊动强度与光滑床面坡面流变化趋势相似。流向紊动强度随相对水深的增大而减小。随着粗糙度增大 ...
谷方正 +4 more
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How identity bias affects perceptions of conservation messages on social media
Conservation Biology, EarlyView.Abstract Public support is essential for conservation, as public opinion can influence decision‐making and policy. Therefore, understanding whether bias toward conservationists due to their identity (identity bias) affects their perceived credibility and support for their recommendations is important.
Lauren F. Rudd +4 more
wiley +1 more source
Visible‐Light‐Excited Optical Thermometry in Ca3Sc2Si3O12: Er3+ via an Efficient Eu2+ Bridge
Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT Er3+ ions are promising for optical thermometry due to their thermally coupled levels. However, their parity‐forbidden transitions result in weak and narrowband absorption, which restricts excitation to infrared lasers (e.g., 808, 980, or 1550 nm). Moreover, the single emission center inherently limits temperature sensitivity. In this work, we
Yi Liu +6 more
wiley +1 more source
Enhanced Magnetocaloric Effect in Tb‐Co‐Ni Magnets via Chemical Pressure
Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT Magnetic refrigeration materials are significantly needed in versatile modern industries, including scientific research, aerospace, and health care, due to their potential applications in gas liquefaction and storage. Herein, a significantly enhanced magnetocaloric effect with a suitable operation temperature range of 53–114 K and a giant ...
Lei Xi +11 more
wiley +1 more source
Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT In electrocatalysis, traditional single‐atom catalysts (SACs) face challenges in achieving coordinated control of reaction pathways due to limitations such as single local energy levels and carrier recombination. By introducing an additional defect structure, it is possible to break the electronic structure symmetry, thereby activating SACs ...
Juanjuan Huo +8 more
wiley +1 more source
Shuitu Baochi Xuebao, 2022 细沟侵蚀产沙是黄土高原水蚀风蚀交错区坡面侵蚀产沙的主要来源,明确该区细沟侵蚀过程特征及其影响因素,对有效防控入黄泥沙和维护流域安全具有重要的科学意义和实践价值。选取水蚀风蚀交错区下垫面典型风沙土为研究对象,通过不同流量(3,5,7,9,11 L/min)、不同坡度(9°,12°,15°,18°,21°)组合下的室内水槽冲刷试验定量揭示风沙土细沟分离过程对坡度、流量以及流速的响应关系,并建立分离能力方程。结果表明:(1)分离能力对坡度和流量的响应均呈线性正相关关系,且相关性极显著 ...
朱启明 +6 more
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Functional Ecology, Volume 40, Issue 7, Page 2068-2082, July 2026.Read the free Plain Language Summary for this article on the Journal blog. Abstract Grasslands worldwide are experiencing severe degradation due to overgrazing, climate change and anthropogenic disturbances, resulting in substantial declines in biodiversity and ecosystem functioning.
Xiaoqi Wang +5 more
wiley +1 more source
Functional Ecology, Volume 40, Issue 7, Page 2128-2142, July 2026.Read the free Plain Language Summary for this article on the Journal blog. Abstract Soil organic nitrogen (SON) transformation is critical for global nutrient cycling and ecosystem productivity, yet how its responsiveness to climate change differs across diverse land use types remains poorly resolved.
Xinyi Yang +10 more
wiley +1 more source