Results 31 to 40 of about 1,172,969 (169)
本文讨论了服从正态分布的强度变量在(分布不一定相同的)多个独立应力作用下的结构可靠性估计.在假设应力参数已知,强度参数部分未知或全部未知的条件下,给出了结构可靠度的点估计和置信下限.
XuMingmin(徐明民) +1 more
doaj +1 more source
Atom Probe Tomography‐Based Analysis of Residual Trace Elements in Advanced Metallic Materials
ABSTRACT Residual trace elements inherited from raw materials strongly influence the mechanical and environmental performance of advanced metallic alloys and recycling materials due to preferable boundary/interface segregation and resultant embrittlement effects, yet their parts per million level concentrations pose significant challenges to ...
Congcong Li +17 more
wiley +1 more source
ABSTRACT Catalytic NH3 decomposition has garnered substantial attention for hydrogen transformation and storage. Ni‐based catalysts continue to suffer from limited thermal stability and suboptimal low‐temperature activity, largely attributed to an incomplete understanding of the structure‐activity relationships and reaction mechanisms governing their ...
Tao Wen +8 more
wiley +1 more source
磁应变法近年来在工程结构残余应力检测方面得到了迅速发展,具有设备简单、操作方便等优点,能方便得到残余应力分布形式,但数值精度不高。采用热轧H形钢加载回弹试验制作了标准残余应力试件,利用磁应变法和盲孔法分别测试了残余应力。通过与有限元计算结果比较发现,盲孔法测得残余应力分布和数值均与计算结果吻合良好。磁应变法测得的残余应力分布正确,但数值随不同处理方法精度不同。研究了提高磁应变法数值精度的方法,得到了采用峰值残余应力处盲孔法数值为基准可有效提高测试精度的重要结论。
王嘉伟 +4 more
doaj
ABSTRACT The strength and ductility trade‐off in titanium matrix composites (TMCs) is a critical factor limiting their widespread application. In this study, a (TiB + TiC)/Ti–6Al–4V composite with an optimal balance between strength and ductility was engineered via multi‐directional forging.
Chunyu Shen +8 more
wiley +1 more source
目的分析两种套筒冠义齿修复牙周病伴游离端缺失基牙应力分布,为牙周病牙列缺损修复方法选择提供理论依据。方法应用三维有限元方法比较分析支持型套筒冠义齿与沟槽套筒冠义齿修复牙周病伴游离端缺失基牙应力峰值及应力分布情况。结果沟槽套筒冠义齿基牙最大应力为3.05 Mpa,支持型套筒冠义齿应力峰值为3.33 Mpa,两种义齿均在远下斜向加载牙槽骨吸收达2/3时应力最大,在垂直加载牙槽骨正常时应力最小。支持型套筒冠基牙应力集中较沟槽套筒冠更偏向于牙颈部。结论沟槽套筒冠义齿基牙应力小于常规支持型套筒冠义齿 ...
王伟, 张艳, 袁琳
doaj
Effects of parachute science on local research capacity 降落伞科学对当地研究能力的影响
Abstract Strengthening research capacity is essential to address the global biodiversity crisis. Yet, parachute science often undermines this goal, and its prevalence, costs, and benefits are unclear. We analyzed 13,502 publications on primate research that we extracted from Scopus (1960–2022) to evaluate the effects of parachute science on local ...
Li Yang +11 more
wiley +1 more source
本文以尾流振子模型为基础,通过改进Lyong的半经验公式法,研究了张力腿的张力变化以及流场分布对张力腿涡激振动响应的影响.计算结果表明,张力腿的张力改变,使各阶模态的锁频区域分布发生变化,从而改变了结构的涡激振动响应;流场分布的响应计算表明,同样的流场分布对不同阶模态的激励作用的效果不同 ...
王艺, 陈伟民
core
220 kV SF6断路器瓷套的胶装部位应力分析及其优化设计
展开断路器的应力分析,研究其胶状部位的应力分布,对提高电气设备的安全运行具有重要意义。运用有限元的方法,计算了胶装部位结构参数设计下的断路器瓷套的应力分布。结果表明:适当加大胶装比、下胶装部位瓷套外径,合理选择法兰与瓷套之间的厚度和法兰内表面齿形结构,均可在一定程度上优化断路器的应力分布,从而提高其整体机械强度。
石忠强 +4 more
doaj
Abstract Achieving global conservation policy goals requires the ability to set and measure progress toward science‐based targets for biodiversity. The species threat abatement and restoration (STAR) metric was developed to enable actors to set science‐based targets for species.
Louise Mair +17 more
wiley +1 more source

