Results 31 to 40 of about 18,570 (167)
Jianzhu Gangjiegou Jinzhan, 2008 本文对中、日、欧州及美国地震规范地震力计算的结构影响系数的构成进行了分析,认为,美国的结构影响系数中包括了材料的强屈比、超静定结构体系的超强系数以及延性系数;而欧洲的结构影响系数包含了延性系数,对于延性好的结构还允许包含结构体系的超强系数;日本仅包含延性系数;我国也是仅包含延性系数。由于日本采用允许应力设计,还有一个1.4的安全系数,因此比较起来,日本的地震力最大。从结构影响系数的构成看结构在地震作用下产生塑性变形的深度,按照美国规范设计的结构塑性变形要求最高,欧洲次之,我国再次之 ...
童根树, 赵永峰
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Rare Metals, Volume 45, Issue 4, April 2026.ABSTRACT In this study, a newly developed seeded electromagnetic confinement directional solidification (EMCDS) technique was employed to fabricate large‐scale TiAl single crystal ingots with a diameter of 32 mm, overcoming the long‐standing size limitations that have hindered their industrial application.
Wei Wang +9 more
wiley +1 more source
Rare Metals, Volume 45, Issue 4, April 2026.ABSTRACT This study introduces a novel velocity‐iterative directional annealing (IDA) strategy to overcome stagnation challenges in columnar grain growth of Ti‐48Al‐2Cr‐2Nb alloys. By dynamically adjusting hot zone migration rates across iterative cycles, the IDA protocol achieved 92.2% synchronization between anisotropic α‐grain boundary (GB ...
Zedong Liu +6 more
wiley +1 more source
Dianci bileiqi, 2017 飘弧和弧道在湿污表面沿泄漏距离的延伸是局部电弧演变的主要环节。利用高速摄像机观测了不同极性直流局部电弧在湿污表面的演变过程,并从气体放电理论分析和解释了出现上述现象的原因。观测结果表明,负极性电弧比正极性电弧飘弧更严重,且负极性电弧延伸速率高于正极性电弧;电弧延伸过程中,正极性电弧更容易出现分叉和并列弧道的现象,负极性电弧更易出现尖状的头部。负极性电弧更易飘弧是由于电弧与污层之间的流注更易发展,使负极性电弧和污层之间更易保持良好的导电通道,所以飘弧更易维持,也更严重;正极性电弧端部紧贴污层表面 ...
金巧芳, 李亚伟
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Rare Metals, Volume 45, Issue 4, April 2026.ABSTRACT This study presents an assessment of four representative expansive additives—calcium sulphoaluminate–calcium oxide, magnesium oxide, sodium lauryl sulfate, and sodium abietate—and their effects on the expansion behavior, mechanical development, and microstructural characteristics of cemented paste backfill (CPB).
Lijie Guo +5 more
wiley +1 more source
Jianzhu Gangjiegou Jinzhan为了研究大高宽比矩形钢管混凝土柱的压弯性能，对大高宽比钢管混凝土短柱进行偏压试验并结合有限元模拟补充了4组试件进行对比，包括不同偏心率、高宽比、钢管壁厚度、截面尺寸情况下柱性能的对比分析。最后参考常用的4本国内外规范进行柱承载力计算，对比并判断现有规范是否适用。结果表明：试件破坏模式均为长边鼓曲，当荷载小于极限承载力的80%时，横截面高度上的应变分布服从平截面假定；随着偏心率增大，柱延性提升，在偏心率超过0.205后，柱延性开始下降；随着壁厚增加，柱延性提升，在壁厚达到8 mm后，柱延性开始下降 ...
陈安英 +4 more
doaj +2 more sources
Functional Ecology, Volume 40, Issue 4, Page 800-815, April 2026.Read the free Plain Language Summary for this article on the Journal blog. Abstract Studies have shown that organisms may adjust metabolic rates in response to thermal variability, highlighting metabolic plasticity as a key adaptive mechanism. Understanding the extent of metabolic plasticity of an organism is key to predicting its adaptation to climate
Qian Hu +6 more
wiley +1 more source
Integrative Conservation, Volume 5, Issue 1, Page 10-15, March 2026.First confirmed breeding of the Brown Hornbill in China, documented through cooperative feeding in Shangyong Protected Area. ABSTRACT The Brown Hornbill (Anorrhinus austeni), a Near Threatened frugivore, reaches the northern edge of its distribution in southern Yunnan, China, yet breeding had not been previously documented with site‐attributed nests in
Junsong Li +8 more
wiley +1 more source
Guangtongxin yanjiu, 2002 ATM- PON是光纤接入网的重要技术 .文章研究了业务穿越 ATM- PON接入网的延时和延时变化性能 ,着重分析媒体接入控制协议对业务延时和延时变化性能的影响 .研究结论对 ATM ...
苏厉, 金德鹏, 皇甫伟, 曾烈光
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