Results 51 to 60 of about 12,629 (167)
A compressive damage model for a rock considering the microcrack mechanical behavior [PDF]
The contributions of the microcrack sliding and propagation to the rock total deformation, the mixed propagation criterion of the microcrack, and the influence of the rock damage degree on the number of the activated microcracks are not completely ...
Cui LIU +5 more
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Rare Metals, Volume 45, Issue 2, February 2026.ABSTRACT Polycrystalline SnSe thin film materials have gained increasing attention as a promising solution for fabricating microscale, flexible, self‐powered electronic components in the field of thermoelectric (TE) materials and devices. However, it is still a great challenge to simultaneously achieve preferred crystal orientation and optimize carrier
Wenxia Li +10 more
wiley +1 more source
Shiyou jixie, 2012 为了了解内压作用下含裂纹射孔套管临界开裂应力，为现场确定泵压等施工参数提供参考依据，用ANSYS有限元分析软件建立了射孔套管有限元模型，给出了含孔边裂纹射孔套管应力强度因子计算公式，对内压作用下含裂纹射孔套管临界开裂应力进行分析计算，得到了临界开裂应力与纵向裂纹长度的关系曲线。研究结果表明,套管最大应力集中在孔边裂纹处，在内压产生的应力作用下裂纹有可能沿轴向产生脆性扩展，因此，孔边裂纹大大削弱了射孔套管的强度；射孔套管临界开裂应力随裂纹长度的增加而减小；在短裂纹区（10 mm＜a＜20 mm ...
许爱荣, 邹云, 杨向同, 窦益华
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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
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, 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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Research on deep hole convergence energy blasting for increasing permeability in deep wells with high gas and low permeability coal seams [PDF]
With the gradual deepening of coal mining, the issue of high ground stress will be faced. In response to the unclear understanding of the internal damage and fracture evolution of deep wells with high gas and low permeability coal seams under the ...
Guodong QIAO +6 more
core +1 more source
Coalition Opportunity Structures and Advocacy Coordination in Consensus and Majoritarian Democracies
Policy Studies Journal, Volume 54, Issue 1, February 2026.ABSTRACT Research on advocacy coalitions suggests that belief homophily—the tendency of actors to coordinate based on shared policy beliefs—drives coalition formation. However, coalition opportunity structures, which are shaped by institutional contexts, may influence the extent to which belief homophily matters.
Keiichi Satoh +7 more
wiley +1 more source
, 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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Nitrogen Anchoring Effect Triggering Improved Reversible Hydrogen Storage of Mg(BH4)2
Rare Metals, Volume 45, Issue 1, January 2026.ABSTRACT This research uncovered the influence of nitrogen‐doped MXene Ti3CN on the reversible hydrogen storage properties of Mg(BH4)2. The Mg(BH4)2‐20Ti3CN composite began releasing hydrogen at a temperature of 80°C. In addition, the composite discharged over 8.8 wt% hydrogen at a comparatively lower temperature of 270°C, whereas the pure Mg(BH4)2 ...
Zhen‐Xuan Ma +7 more
wiley +1 more source
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
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