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缺陷连续统理论及其在本构方程研究中的应用 Ⅱ.缺陷的规范场理论
, 1989 详细评述了缺陷连续统的规范场理论,该理论是近代材料科学和固体力学中新发展起来颇有意义的一个分支。首先强调了Noether定理及其逆定理在构造缺陷规范场理论中的重要性。同时基于Yang-Mills普适规范场构造,包括对SO(3)T(3)群的最小替换和最小耦合原理,系统地介绍了Golebiewska-Lasota,Edelen,Kadic和Edelen等人的原始性工作及他们的贡献。本文表明,Kadic和Edelen的理论是基于一组缺陷动力学的线性连续性方程发展起来的 ...
王文标, 段祝平, 黄迎雷
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Gaoya dianqi, 2021 较之实验室人为模拟的缺陷试品而言,选用实际的含缺陷的GIS绝缘子进行实验研究更能够反映变电站现场的局部放电情况,并更为真实地模拟现场闪络事故的产生过程。但是实际绝缘子上所含的缺陷通常是未知的,因而需要先对缺陷在绝缘子上的位置进行示踪,以了解缺陷的具体形式,为后续的进一步的研究提供基础。文中以一个含有未知缺陷的GIS支柱绝缘子为例,通过光电效应、红外成像、不同气体条件下的放电特性变化等多种手段尝试示踪缺陷的具体位置,最终通过高精度断层扫描确定了缺陷的具体形式 ...
徐洋, 刘卫东, 高文胜
doaj
Rare Metals, Volume 45, Issue 9, September 2026.ABSTRACT Rationally selection of precursor additives during perovskite crystallization is essential for obtaining high‐quality films and achieving high‐performance perovskite solar cells (PSCs). However, the discovery and optimization of effective additives still rely heavily on time‐consuming and costly trial‐and‐error experiments.
Zhimin Feng +12 more
wiley +1 more source
Rare Metals, Volume 45, Issue 9, September 2026.ABSTRACT Additive manufacturing of zinc‐magnesium (Zn‐Mg) alloys via laser powder bed fusion (LPBF) has gained significant recognition as a promising candidate for bone repair. However, the presence of coarse yet brittle eutectic phases in the fabricated Zn‐Mg alloys tends to induce premature stress concentration and resultant fracture during ...
Zhi Dong +10 more
wiley +1 more source
Rare Metals, Volume 45, Issue 9, September 2026.ABSTRACT Aiming at the problems of insufficient forming quality and poor surface performance in the preparation of Ti‐6Al‐4V alloy by laser powder bed fusion (LPBF), this study proposed a laser in situ forging additive manufacturing (LIF‐AM) technology, which integrates LPBF with femtosecond laser in situ shock forging and realizes defect control and ...
Peng He +10 more
wiley +1 more source
Gaoya dianqi, 2017 利用有限元分析软件Ansys建立三维模型,对高压开关柜母线室中触头盒存在气泡缺陷的情况进行仿真计算,研究了在交流情况下气泡缺陷、不同大小的气泡、不同位置的气泡以及不同电压等级对触头盒气泡缺陷附近电场的影响。结果表明:缺陷的出现使缺陷中电位在气泡上半部分集中;缺陷附近的电场强度出现明显的畸变,缺陷中心电场强度变大;缺陷越大,电场畸变越大;缺陷的位置对电场的畸变并没有太大的影响;电压等级的提高使缺陷中电场的畸变更加明显。
操李节 +5 more
doaj
Wildlife Letters, Volume 4, Issue 3, Page 107-117, September 2026.Human‐caused leopard deaths in Sri Lanka averaged 9.65 ± 4.5 records year−1 over 17 years (2008–2024; n = 164), with records highly clustered in the central highland mosaic ecosystem. Mortality was dominated by adult males and driven primarily by snaring in plantation landscapes, and indicating an increase approximately 0.7–0.8 deaths per year.
Sanjaya Weerakkody +11 more
wiley +1 more source
Gaoya dianqi, 2021 利用特高频局部放电检测方法及时发现并处理气体绝缘金属封闭开关设备（GIS）内部固体绝缘缺陷,是GIS设备运维的重要手段。目前将异常特高频信号与现行标准、规范和典型模拟缺陷图谱进行比对从而诊断缺陷类型及严重程度的方法,因现场情况复杂、设备结构各异,准确性有待进一步提升。因此文中针对现场检测中发现的GIS固体绝缘表面放电缺陷和内部气隙放电缺陷,研究该类缺陷所激发特高频局部放电信号的PRPS统计图谱特征,并利用傅里叶变换和连续小波变换分析单次特高频原始脉冲的频谱特征和时频特征 ...
周电波 +6 more
doaj
Advances in Thermoelectric Cu2ZnSnS4: From Structure, Synthesis to Performance
Rare Metals, Volume 45, Issue 8, August 2026.ABSTRACT Thermoelectric technology has the capacity to directly convert waste heat into electricity and vice versa. For a long time, Cu2ZnSnS4 (CZTS) has been extensively researched in the domains of solar cells and photocatalysis due to its exceptional photovoltaic properties, but its wide bandgap prevents it from being favored in thermoelectrics ...
Xiaojun Li +3 more
wiley +1 more source
Rare Metals, Volume 45, Issue 8, August 2026.ABSTRACT To address critical issues in lithium–sulfur batteries, such as slow polysulfide conversion kinetics and shuttle effects, we designed and synthesized a high‐performance nanoalloy catalyst through a defect reconstruction strategy, aiming to enhance the electrochemical performance of batteries.
Zhijun Zhao +10 more
wiley +1 more source