Results 41 to 50 of about 18,690 (174)

鲜水河断裂带南北构造差异性的地球物理分析

open access: yesDizhen xuebao, 2019
对鲜水河断裂带重磁异常进行向上延拓,通过计算观测面高度异常与延拓后异常之间的相关系数得出最佳向上延拓高度,该延拓高度所对应的延拓结果即为研究区构造背景产生的异常值。向上延拓结果显示布格重力异常值沿鲜水河断裂带自北西向南东逐渐增大,反映出下地壳底边界沿该方向呈升高趋势,可能由青藏高原地壳软弱物质 “东向逃逸” 所致。化极后ΔT磁异常延拓结果表明鲜水河断裂带南东段的康定—石棉以东为强磁性刚性基底。以鲜水河断裂带为分界的不同地块之间基底岩石及地层物性的不同是断裂带南北磁性差异的主导原因 ...
Yifei Ai, Jian Zhang
doaj   +1 more source

The Effect Analysis of Environment on Microstructure,Fracture Model and Mechanical Properties of Continuous Silicon Carbide Fibers [PDF]

open access: yes, 2005
耐高温、高性能连续SiC纤维在航空航天和先进武器装备中具有特殊重要地位。SiC纤维作为陶瓷基复合材料的增强相(即复合材料的骨架),要求在高温服役环境下具有优良的热物理化学与力学性能的稳定性,这些性能显然与纤维的组成和微结构有关。因此,研究高温和有氧气氛处理对纤维的力学性能与微结构的影响,对于认识SiC纤维在服役环境下的失效机理,正确评价纤维的高温环境性能,指导纤维组分与微结构设计具有重要指导作用。国外从上世纪90年代末已经开始在这方面进行了一些研究 ...
王艳艳
core  

Electronic Modulation of CoNi Nanoparticles by N‐Doped Carbon for Efficient Lignin Hydrogenolysis to Aromatic Monomers

open access: yesRare Metals, Volume 45, Issue 3, March 2026.
ABSTRACT Cost‐effective and efficient non‐noble‐metal catalysts for selective lignin hydrogenolysis remain elusive, representing a significant challenge in biorefinery. Here, we prepared a nitrogen‐doped carbon supported CoNi bimetallic catalyst, which was successfully derived from zeolitic imidazolate framework (ZIF) via high‐temperature pyrolysis ...
Xingwei Luo   +3 more
wiley   +1 more source

高压开关用铸态拐臂断裂失效分析

open access: yesGaoya dianqi, 2015
某型号高压开关用铸态拐臂在试验过程中发生断裂,通过宏观检验、化学分析、金相检验、扫描电镜与能谱分析等方法对铸态拐臂断裂的原因进行了分析。结果表明:非金属夹杂是裂纹源萌生的地方,随后裂纹不断扩展,最终导致球墨铸铁拐臂断裂失效。拐臂的断裂机制为解理+沿晶界的混合型断裂,连续分布的皮下气孔也是促使拐臂断裂的原因。
王建伟, 何佳, 赵涛, 邹新峰
doaj  

基于遗传算法的地震烈度衰减参数反演方法及应用

open access: yesDizhen xuebao, 2020
收集郯庐断裂带中南段59次地震的等震线数据,运用遗传算法,将郯庐断裂带中南段按照断裂带东侧和西侧分区,分别反演其地震烈度衰减参数,反演时使目标函数的一范数最小,同时对烈度衰减曲线的远场施加约束,通过自助抽样(Bootstrap)技术多次重复反演以对反演结果的稳定性进行评价,并将断裂带东侧和西侧的烈度衰减曲线分别与第五代地震动参数区划图进行对比。结果表明:使用本文提出的方法进行反演可使烈度衰减曲线即使不进行近、远场补点,也能收敛;断裂带东侧和西侧的结果均与第五代地震动参数区划图的结果存在差异 ...
Yicheng He   +5 more
doaj   +1 more source

预测腐蚀管道剩余强度的新方法 [PDF]

open access: yes, 2004
将BP神经网络和遗传算法相结合 ,得到了一种可计算腐蚀管道剩余强度和最大允许注水压力的新神经网络。通过实例分析 ,将 7种常用规范和改进的遗传神经网络方法进行了比较。结果表明 ,不同计算方法得到的剩余强度和最大允许注水压力相差较大 ,Wes 2 80 5 - 97规范、ASMEB31G规范、CVDA— 84规范、Irwin断裂力学方法等都比J积分方法的剩余强度和最大允许注水压力偏大 ;Burdiken和DM断裂力学方法计算得到的剩余强度和最大允许注水压力比J积分偏小 ...
付道明   +4 more
core  

A Stretchable Sandwich Composite Film With Ultra‐Broadband Electromagnetic Interference Shielding and High‐Performance Photothermal Conversion Capability

open access: yesRare Metals, Volume 45, Issue 3, March 2026.
ABSTRACT With the rapid growth demand for advanced integrated electronic systems, lightweight flexible electromagnetic interference (EMI) shielding films integrated with functional properties, such as excellent mechanical properties and self‐healing capability, are a research focus in high‐tech functional materials. Herein, a sandwich‐structured aramid
Dan Guo   +9 more
wiley   +1 more source

Experimental and theoretical analyses of three-dimensional surface crack propagation [PDF]

open access: yes, 2017
2011-2012 > Academic research: refereed > Publication in refereed journalVersion of ...
Han, ZC   +4 more
core  

The Dependence of Properties on Structural Features in Macro/Micro Levels for PBF‐LB Fabricated Porous NiTi Alloy

open access: yesRare Metals, Volume 45, Issue 2, February 2026.
ABSTRACT Porous NiTi alloys are widely used in biomedical and engineering fields. Using the PBF‐LB technique, the TPMS and Voronoi porous parts with a porosity of ∼67% and a minimum feature size of 0.15 ± 0.02 mm were fabricated. Although the bulk sample fabricated with the same parameters is defect‐free, μ‐CT reconstruction on the porous sample ...
Wen‐Hao Zeng   +7 more
wiley   +1 more source

Achieving Excellent Strength–Ductility in Nb‐Si Superalloys via Stable Bi‐Phases Structure and Nano‐Precipitation Behaviors

open access: yesRare Metals, Volume 45, Issue 2, February 2026.
ABSTRACT Nb‐Si‐based superalloys are considered as the most potential candidate materials for nickel‐based superalloys due to the lower density and higher using temperature. Here, a type of stable Nbss/γNb5Si3 bi‐phases structure with a coherent interface has been successfully designed. Additionally, the Nbss and γNb5Si3 phases showcase the orientation
Xiao‐Wei Wang   +6 more
wiley   +1 more source

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