Results 61 to 70 of about 11,139 (167)
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
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Dianci bileiqi, 2012 复合绝缘子端部金具和芯棒装配的压接式工艺是靠金具和芯棒间的形变应力产生的静摩擦力承担机械强度。金具和芯棒二者之间的材质不同,热膨胀系数也不同,当受热后金具和芯棒的形变也随之改变,因此,理论上说受热对压接强度有一定的影响。笔者通过对比试验得出:一定范围内的温度变化对压接式复合绝缘子的性能没有影响。
侯建峰, 马西武, 金强
doaj
, 1987 本文研究一次拉伸型过载对奥氏体不锈钢疲劳裂紋近门槛值扩展的影响.试验结果表明,过载对门槛值的影响和过载比P_0/P_(max)的大小有关;P_0/P_(max)>1.4时,门槛值随着过载比增加而线性提高.提出了裂纹扩展速率减缓和门槛值提高的主导原因是过載大大促进裂纹顶端闭合 ...
邓蓉英
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An integrated DIC and CPG investigation of the model-I fracture features for granites after cyclic heating-cooling treatments [PDF]
The thermo-mechanical properties of deep reservoir rocks, especially the damage and failure characteristics under heating-cooling cycles, are of great importance to the stability analysis of well wall and the evaluation of geothermal extraction ...
Gan FENG +5 more
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Shuitu Baochi Xuebao, 2019 通过应用数据挖掘和数据整合方法，以建立我国土壤渗透性数据库，并对影响土壤渗透性的各因子综合分析，揭示土壤渗透性的区域变化规律。结果表明：（1）土壤渗透性呈现明显的区域性变化，表现为西南地区 < 华北地区 < 东北地区。西南地区土壤渗透力最差，稳渗速率对数值为-0.5~-2.0；华北、东北地区整体数值均在0.5以上，土壤渗透力较强。（2）在影响土壤渗透力的各因子中，气候类型及林龄通过影响植被来间接改善土壤渗透力；植被能有效提升土壤渗透力，但不同植被类型间土壤渗透力并无显著差异；随土层深度的增加 ...
丁海晶, 姜姜, 张金池
doaj
Study on induced mechanism of slurry splitting deviation and diffusion in long hole grouting near faults [PDF]
Affected by complex hydro-geological conditions, mine production is facing serious water hazards, with water inrush and sudden water accidents occurring from time to time.
Lianchong LI +4 more
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Dianci bileiqi, 2005 为了确保伞套间粘接性能,选用特制的粘合剂,采用半机械化套粘伞裙装置,把自动打磨好内口表面的,与护套采用过盈配合的,按内外绝缘强度差1倍所确定内口长度的伞裙套粘在护套上以保证伞套间粘接部位实现硅氧烷分子交链完全,补强剂颗粒表面羟基及分子间范德华力利用充分,没有较大的填充剂颗粒存在的界面,使界面具有较高的机械强度和良好的绝缘性能。伞套间的过盈配合在相应部位所出现的弹变,因其体形网状分子结构中和硅氧烷分子螺旋状态的存在,其蠕变性能极为缓慢,应力松弛现象几乎不存在,伞套间粘接性能是可靠的。
张福林, 段旻
doaj
Gaoya dianqi, 2023 为研究高压电缆附件绝缘在电、热和环境等多因素作用下的老化特性，文中以6种退役硅橡胶绝缘高压电缆附件样品为研究对象开展工作。采用SEM、FTIR和XRD分析了不同运行环境下样品的理化特性和微观分子结构变化，通过介电测试和表面电位衰减测试获得了样品宏观介电性能和微观电荷特性，采用拉伸实验获得了绝缘样品的力学性能数据，最后结合上述表征对电缆附件的绝缘和老化状态进行评估。结果表明硅橡胶附件老化过程中以Si-O主链降解为小分子为主，小分子物质进一步发生氧化和重结晶反应，导致分子的交联度下降和极性增强 ...
景巍巍 +7 more
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, 1991 本文应用霍普金森压杆(SHPB)技术对特种钛合金在高加载率下的动态断裂韧性进行了试验研究,并与静态试验结果进行了比较。结果证明,该合金的动态断裂韧性随着加载率的增高而下降 ...
段祝平, 田兰桥
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Experimental study on the effect of the angle of the shaped charge tube on the penetration enhancement of coal seam blasting [PDF]
In order to solve the problem of poor permeability enhancement effect caused by disorderly expansion of coal cracks in traditional presplitting blasting, the influence of different opening angles of shaped charge blasting cartridge on permeability ...
Guodong QIAO +5 more
core +1 more source