Results 61 to 70 of about 13,971 (184)

Conservation Status, Decline Factors, and Strategies for Globally Endangered Musk Deer (Moschus spp.) in China 中国境内全球濒危麝属 (Moschus spp.) 物种的保护现状、致危因素及应对策略

open access: yesWildlife Letters, Volume 4, Issue 1, Page 42-55, March 2026.
This review summarizes the status of musk deer in China, highlighting severe population declines due to illegal hunting and habitat loss, and proposes integrated conservation strategies including habitat protection, captive breeding, and law enforcement to support the recovery and sustainable management of this ecologically and economically important ...
Feng Jiang   +8 more
wiley   +1 more source

幂硬化材料圆锥压入完整塑性区的应力分布模型

open access: yesSCIENTIA SINICA Physica, Mechanica & Astronomica, 2022
Hui Chen   +6 more
semanticscholar   +1 more source

Research on Key Issues in Eddy Current Nondestructive Evaluation of Residual Stress in Aluminum Alloy [PDF]

open access: yes, 2015
铝合金作为制造业发展的基础材料,在航空航天、高速铁路、建筑工程、船舶制造、汽车工业等支柱产业中有着重要地位。残余应力往往是造成铝合金结构破坏的重要因素。有效的评价应力状态,特别是导致损伤出现的临界应力状态是评价设备结构强度、可靠性的重要依据。传统的无损检测方法已广泛应用于工程实际中,但大部分局限于对已成型的缺陷进行检测。对于可能导致损伤出现的隐性、不规律变化的残余应力状态的评价则较为困难。 目前,应用较多的残余应力检测法主要有盲孔法、X射线法、超声波法以及磁测法。这些方法在使用上都存在很大的局限性 ...
汪涛
core  

Cluster‐Driven Strengthening and Oxide Stripes‐Induced Embrittlement in Internally Oxidized AgMg Alloys

open access: yesRare Metals, Volume 45, Issue 2, February 2026.
ABSTRACT Internal oxidation has been identified as an effective method for enhancing the strength of AgMg alloys. However, the concurrent occurrence of embrittlement remains inadequately understood, thus limiting their broader application. This study investigates the oxidation behavior of AgMg alloys with Mg concentrations ranging from 1 at% to 7 at ...
Hai‐Cheng Zhu   +12 more
wiley   +1 more source

压缩式封隔器坐封力学有限元分析

open access: yesShiyou jixie, 2012
封隔器胶筒与套管的接触压力是衡量密封性能的重要依据。应用ANSYS有限元软件,数值模拟了封隔器坐封后的应力、应变分布及接触状态,得出胶筒的整体接触压力分布和上、中、下3个胶筒与套管接触压力的分布规律。线性回归了坐封力与接触压力的关系式。指出封隔器各胶筒与套管的最大接触压力随着坐封液压力的增大而增大,并且上、中胶筒呈线性关系,下胶筒呈二次曲线关系。
尹飞, 高宝奎, 金磊
doaj  

Strength Calculation of Harmonic Gear Reducer in Assembly and Dynamic Operation Process [PDF]

open access: yes, 2017
自从C.W.Musser发明了谐波齿轮减速器并运用到火箭上后,由于它的传动比大、重量轻、可靠度强、体积小、传动精度高等优点而倍受关注。我国从两弹一星开始,在大力发展航天事业的背景下,谐波齿轮减速器被广泛地运用到火箭及卫星的传动机构中。但国内对于谐波齿轮减速器的失效机理和结构优化及多样化等方面还需深入研究,尤其缺乏对其动态运转强度较为精确的计算和对其疲劳寿命的评估。 针对上述问题,本文研究谐波齿轮减速器的强度与失效机理,给出了一种基于应力-寿命法的疲劳预测过程,并对谐波减速器的结构进行了改进 ...
杨健
core  

高建钢厚壁H型钢残余应力测试研究

open access: yesJianzhu Gangjiegou Jinzhan, 2010
近年来,国产高性能建筑结构用钢由于其优良的力学性能,特别是强度对厚度的不敏感性,在国内大跨和高层建筑钢结构中得到了越来越多的应用,但现行相关设计规范中仍缺乏其基于设计可靠度分析的合理设计指标。高建钢常用作厚壁H型钢柱,其残余应力分布对构件承载力影响较大,是分析高建钢基本构件设计可靠度的关键因素之一。本文采用条形切割法,对80mm厚高建钢Q345GJ焊接H型钢的纵向残余应力分布进行了详细的测试试验研究。根据试验数据,得到80mm厚高建钢Q345GJ焊接H型钢残余应力分布图 ...
李元齐   +4 more
doaj  

Effect of double abutment absorption of alveolar bone in rigid fixed bridge on the stress distribution of abutments [PDF]

open access: yes, 2012
目的:探讨固定桥双基牙侧牙槽骨有不同程度水平吸收时,基牙牙周膜的等效应力值和分布的变化,以指导临床固定桥的合理设计。方法:采用螺旋CT扫描技术与MIMICS、AnSyS软件相结合建立双基牙侧牙槽骨有不同程度水平吸收后的三基牙双端固定桥的三维有限元模型,施加垂直和斜向45°载荷,分析双基牙侧牙周膜的应力分布状况。结果:1斜向载荷下各模型应力值均大于垂直向载荷时的应力,应力集中现象也较垂直向载荷时明显;2在垂直或倾斜载荷下,有牙槽骨吸收的第二前磨牙侧增加牙周组织健康的第一前磨牙时,应力均变大以分担牙合力 ...
吴娴   +4 more
core  

Analysis of collapse modes of stiffened panels subjected to combined axial and lateral loads [PDF]

open access: yes
ObjectiveThis study analyzes the influence of lateral loads on the ultimate strength and collapse modes of stiffened panels subjected to combined loads.
Deyu WANG, Guangyu GUO, Jinju CUI
core   +1 more source

252 kV三相共箱盆式绝缘子应力测试与分析

open access: yesGaoya dianqi, 2021
通过水压试验和仿真分析,研究了252 kV三相共箱盆式绝缘子的机械特性,得到了三相共箱盆式绝缘子的应力分布及薄弱位置。在水压试验中实时测量了盆式绝缘子的应变,得到了绝缘子的应力分布和变化;对绝缘子水压过程进行了仿真分析,仿真结果与试验结果一致。研究结果表明:三相共箱盆式绝缘子破坏压力值为2.6 MPa,对应的最大破坏应力为78.28 MPa;水压破坏呈脆性破坏;绝缘子的薄弱位置是弧面曲率变化最大处。
徐鹏飞   +10 more
doaj  

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