Results 51 to 60 of about 11,139 (167)
Zhejiang Daxue xuebao. Lixue ban, 2015 应用NCEP再分析资料，分析了2008年8号台风“凤凰”生成和发展过程中大尺度稳定凝结潜热、积云对流潜热和海面感热3种热力因子的作用.结果表明：对流凝结潜热释放是台风“凤凰”维持和发展的主要热力因子，积云对流潜热释放不但使台风中心增暖并使台风中间层上升运动增强，从而促使台风加强和发展；海面感热通过海气相互作用使海面凤及对流层涡度增强，可能是台风初始低压的形成机制；大尺度稳定凝结潜热在台风发展过程中虽然值较小，但其通过影响台风眼区的垂直下沉气流，可促使台风暖心低压进一步发展.
YINXianlong(尹先龙) +1 more
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Water inrush mechanism and the minimum safety thickness of the rock wall of a tunnel crossing a fault fracture zone [PDF]
Objective With the relocation of major national strategic plans to western China, railway construction has gradually focused on the complex and dangerous mountainous regions of Yunnan, Sichuan, and Xizang Provinces, where the proportion of tunnels along
XIAO Kun, YUAN Dong
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Rare Metals, Volume 45, Issue 1, January 2026.ABSTRACT High‐entropy alloys (HEAs) have emerged as a transformative class of materials distinguished by their complex chemical compositions, unique microstructures, and remarkable mechanical and functional properties. Traditionally, the discovery and optimization of HEAs have relied on conventional methods, including trial‐and‐error experimentation ...
Chrispin Ouko Zamzu +2 more
wiley +1 more source
Jianzhu Gangjiegou Jinzhan, 2021 由于冷成型钢材与传统热轧钢存在材料和制作工艺上的不同,导致二者在高温环境下具有不同的力学表现行为。探讨了一种冷成型钢材在不同温度下的力学性能,试件分别取自截面尺寸为600mm×16mm,700mm×20mm,800mm×22mm的方钢管,取件位置包括方钢管的平板区、转角区和焊缝处。试验采用稳态试验的方法分别将试件从常温至700℃的环境下拉断,试验共进行49组。试验获得的力学指标包括弹性模量、屈服强度、抗拉强度、极限拉应变、断裂应变以及几个特征强度 ...
刘红波 +3 more
doaj
Rare Metals, Volume 45, Issue 1, January 2026.ABSTRACT Carbon dots (CDs) have emerged as promising modifiers for boosting the photocatalytic H2O2 production, yet their precise role remains to be quantitatively elucidated. Herein, S, N‐codoped lignin‐derived carbon dots (SN‐LCDs) and lignin‐derived carbon dots (LCDs) were synthesized and employed to modify TiO2.
Bin‐Peng Zhang +6 more
wiley +1 more source
, 1994 本文在Peieris框架下对裂纹尖端位错成核与发射问题进行了严格的数学分析。在修正Rice设想的基础上;建立了一组新的控制方程。应力场与位错密度场分别表示成第一类与第二类切比雪夫多项式的级数。相应的张开位移与滑错位移可以用三角级数表示。通过离散的方法;控制方程转化为一组非线性代数方程。用Newton—Raphson方法求解这组方程;得到远场为纯剪、纯拉及两者复合情况下的解答 ...
王自强
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Rare Metals, Volume 45, Issue 1, January 2026.ABSTRACT Diffusion bonding (DB) of near‐α titanium alloys requires high temperatures, which can cause grain coarsening, structural deformations, and degradation of the workpiece's mechanical characteristics. In this study, thermal hydrogen processing (THP) was applied to Ti65, combined with selective magnetron sputtering of a Ti‐Al thin film to promote
Liang‐Wei Kang +9 more
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Gaoya dianqi, 2014 笔者通过试验并分析了三相不通孔盆式绝缘子水压试验过程中的应力变化,结合盆式绝缘子的生产工艺,确定了浇注件内应力特别是金属嵌件周围内应力大是造成水压破坏的根本原因,而填料品质及嵌件周围导电橡胶质量则是决定内应力大小的主要材料因素,控制导电橡胶、填料的技术指标,避免嵌件与浇注体粘接不良,防止填料在浇注料中沉降,优化固化工艺,注意过程设备及工装质量等是降低内应力、保证生产过程盆子水压强度稳定的有效措施。
费龙菲, 龚晓燕, 陈维
doaj
, 1984 本文用三点弯曲试样测定15MnVN钢在淬火和200℃低温回火状态下疲劳裂纹扩展速率。试验在循环载荷比R=0.5的恒幅条件下进行,并利用金属塑性变形在光滑表面上产生浮凸的现象,用相衬显微镜测定裂纹顶端单调塑性区尺寸。在平面应力状态下垂直于裂纹面方向的单调塑性区尺寸与相应的(K_(max)/σ_s)~2成正比,其比例系数为0.21。根据Rice循环塑性区尺寸与单调塑性区尺寸关系,得到垂直裂纹面方向的循环塑性区尺寸与相应裂纹扩展速率之间为一指数关系。在裂纹扩展过程中,相对裂纹尺寸a/W约等于0 ...
于桂清, 李禾, 邓蓉英
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New Phytologist, Volume 249, Issue 2, Page 764-776, January 2026.Summary Fine roots are critical for soil resource uptake, yet how declining plant diversity alters fine root biomass (RB) and traits remains unclear. We tested how plant functional trait dissimilarity in shade tolerance, drought tolerance, growth rate, and nitrogen‐fixation ability drives variation in root attributes.
Sai Peng, Yakun Zhang, Han Y. H. Chen
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