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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

open access: yesJianzhu 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
doaj  

高压断路器瓷套裂纹尖端应力强度因子研究

open access: yesDianci 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
doaj  

基于PIV的渐变地表粗糙度对坡面流水动力特性的影响

open access: yesShuitu 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
doaj  

Genomic responses to increased temperature and pollinator selection in Brassica rapa L.

open access: yesNew Phytologist, Volume 250, Issue 2, Page 1231-1247, April 2026.
Summary Rapid environmental change reshapes both abiotic stress and biotic interactions, yet it remains unclear how these combined forces structure plants' genomic adaptation. In particular, the joint influence of temperature and pollinator identity, two ecological axes undergoing simultaneous global shifts, has rarely been quantified at genomic ...
Yanqian Ding, Florian P. Schiestl
wiley   +1 more source

Progress in Surface‐Enhanced Raman Scattering‐Based Volatile Organic Compounds Detection: Materials, Application, and Prospects

open access: yesRare Metals, Volume 45, Issue 3, March 2026.
ABSTRACT The detection of volatile organic compounds (VOCs) holds significant implications in environmental monitoring and disease diagnosis. Traditional gas detection technologies are constrained by complex operation and high cost, thereby failing to satisfy real‐time detection demands.
Yuening Wang   +11 more
wiley   +1 more source

Coalescence‐Ripening Mechanism of γ′−Ni3(Al, Ti) During Long‐Term/High‐Temperature Operation of Ni‐Based Superalloy Discs

open access: yesRare Metals, Volume 45, Issue 3, March 2026.
ABSTRACT The evolution of the γ′−Ni3(Al, Ti) phase in superalloys is governed by a coupled coalescence‐ripening mechanism driven by elemental diffusion. In this study, thermal exposure experiments were performed at 750°C and 800°C for durations ranging from 100 to 20,000 h.
Zhaotian Wang   +5 more
wiley   +1 more source

3D‐Printed Porous High‐Entropy Alloy Boosts Peroxymonosulfate Activation for Long‐Term Organic Pollutant Degradation

open access: yesRare Metals, Volume 45, Issue 3, March 2026.
ABSTRACT High‐entropy alloys (HEAs) have attracted considerable interest from researchers owing to their tunable chemical compositions, exceptional structural stability, and promising catalytic properties. However, their large‐scale application is often hindered by complex manufacturing techniques and poor durability.
Sheng Guo   +9 more
wiley   +1 more source

黄土高原水蚀风蚀交错区风沙土细沟分离能力探究

open access: yesShuitu 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
doaj  

Interface Issues of Inorganic Solid‐State Electrolytes in Secondary Magnesium Batteries

open access: yesRare Metals, Volume 45, Issue 3, March 2026.
ABSTRACT Solid‐state magnesium batteries (SSMBs) have gained significant attention as promising candidates for next‐generation safe energy storage systems because of the abundance of magnesium (Mg) in the earth's crust, superior energy density, and inherent nonflammability.
Jiren Wang   +9 more
wiley   +1 more source

Exceptional Electromagnetic Wave Absorption in High‐Entropy Carbides Enabled by Lattice Distortion Engineering

open access: yesRare Metals, Volume 45, Issue 3, March 2026.
ABSTRACT The growing concern over human health issues, driven by increasingly severe electromagnetic pollution from 5G communication, has made the urgent development of high‐performance electromagnetic wave (EMW) absorbing materials. Although carbide‐based materials are promising because of their conductive and polarization losses, existing single ...
Chenqiang Duan   +9 more
wiley   +1 more source

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