Results 41 to 50 of about 15,266 (166)
, 2009 通过岩石加载的室内试验方法,测试不同岩石破裂全过程的力学特征及其声发射特性,得到岩石破坏全过程力学特性——岩石的全应力-应变曲线、声发射事件累积数、声发射事件率等相关曲线及参数,给出声发射事件数、事件率与应力水平、时间之间的关系。着重讨论一次性加载过程中塑性变形阶段明显的岩石在加载接近峰值强度时单位时间内的应力增长速度减小,也即这一阶段出现明显的"耗时"现象;并且在此阶段监测到的声发射事件率出现明显下降,出现声发射相对平静阶段;而对于塑性变形阶段不明显的岩石来说,这一阶段则基本不存在明显的"耗时"现象 ...
唐海燕 +3 more
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Damage and failure mechanism of pre-static loaded rock under cyclic impact [PDF]
To study the damage and failure mechanism of rocks under the coupling effect of high ground stress static load and cyclic impact disturbance generated by mining and excavation, the multi-strain rate dynamic static superposition rock mechanics test system
Bing ZHANG +4 more
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Rare Metals, Volume 45, Issue 2, February 2026.ABSTRACT The transformative potential of gallium nitride high electron mobility transistors (GaN HEMTs) in advancing carbon‐neutral power systems remains bottlenecked by contact resistance (Rc) at the metal–semiconductor (M‐S) interface, a critical determinant of switching losses and frequency response.
Ji‐Zhou Zhang +8 more
wiley +1 more source
Shuitu Baochi Xuebao, 2005 应用VanGenuchten提出的土壤水分特征曲线公式,推导出了沙漠风沙非饱和土壤水分特征曲线的分形模型。通过对古尔班通古特沙漠地9种不同土壤样本利用中子水分仪和负压计实测的水分特征曲线资料反求得到相应的分形维数,分析了分形维数与土壤质地之间的关系,结果表明随着土壤质地从流动风沙土、半固定风沙土到固定风沙土的变化,其分形维数呈逐渐增大。此外,基于土壤颗粒的重量与粒径分布求出了古尔班通古特沙漠地风沙土壤粒径的分形维数。通过对土壤水分特征曲线的分形维数与土壤粒径的分形维数的对比 ...
苏里坦 宋郁东 张展羽
doaj
Zhejiang Daxue xuebao. Lixue ban, 2001 河道的自组织结构具有典型的重分形，传统的长度法难以揭示河道形态变化的局域特征，本文提出了连续迭移长度法，将河道沿着伸展方向依据其特征尺度划分为一系列节点，若干个节点组成一个区间，按区间计算分维数值，并使区间按节点连续重迭偏移，取得全河道分形维数的离散点值.试验表明，用连续迭移长度法获得的长江河道分维数的变化特征与中国陆域的构造演化、地理、地质要素有着密切的关系.
SHENXiao-hau(沈晓华) +4 more
doaj +1 more source
Impacts of coal fracture roughness and aperture on the seepage of injected water: An experimental study [PDF]
ObjectiveWater injection into coal seams is recognized as a critical technical measure for dust removal and the prevention and control of coal and gas outbursts and rock bursts in coal mines.
Gang WANG +4 more
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Rare Metals, Volume 45, Issue 2, February 2026.ABSTRACT Regulating negative parameters of metacomposites is mainly limited by their unclear mechanisms, which affects their practical applications in new sensing, communication, electromagnetic (EM) protection and other fields. This work proposes a dual‐functional competitive design strategy based on the waste corncob‐derived carbon/polyaniline ...
Qiuyun Yang +4 more
wiley +1 more source
Shuitu Baochi Xuebao, 2016 以广东省五华县典型崩岗洪积扇为研究对象，通过GPS RTK获取从扇顶到扇缘64个采样点的坐标、高程信息，并采集土壤样品进行理化性质的测定及分析，通过分形理论、回归分析和地统计学相结合的方法研究洪积扇土壤分形特征和空间变异规律，以及分形维数与土壤颗粒组成和养分含量的相关关系。结果表明：土壤颗粒组成和养分含量具有明显分异特征，且与分形维数的空间分布特征呈现出一定的规律性。从扇顶到扇缘，土壤粉粒、粘粒质量分数和养分含量逐渐增加，与分形维数呈显著正相关线性关系，砂粒质量分数则逐渐减少 ...
马 媛 +5 more
doaj
Influence of loading and unloading effect on mechanical properties of impact rock under impact load [PDF]
In order to study the effect of basic roof period pressure on the dynamic characteristics of impact pillar, one-dimensional dynamic and static combined loading SHPB experimental device is used to carry out dynamic impact experiment on the impact ...
Banquan ZENG +2 more
core +1 more source
International Journal of Applied Linguistics, Volume 36, Issue 1, Page 393-408, February 2026.ABSTRACT Acknowledging the limitations of existing measurement instruments in adequately capturing the distinct cognitive processes (e.g., form‐focused vs. meaning‐focused) involved in informal digital learning of English (IDLE), this paper asserts a pressing need to develop and validate robust instruments that measure form‐focused and meaning‐focused ...
Minlin Zou +3 more
wiley +1 more source