Results 71 to 80 of about 1,318 (187)
Zhongshan Daxue xuebao. Yixue kexue ban, 1990 本实验对12例鼻咽癌实体瘤细胞染色体畸变及同一患者外周淋巴细胞的染色体断裂点与已知的脆性部位作了对比分析,在3例中发现有4个肿瘤细胞染色体断裂点,3p24、3p14、5q31和11ql3与其自体脆性部位重合或相邻。而3p24、3P14和5q31属常见脆性部位,11q13既是常见脆性部位,也与叶酸敏感型罕见脆性部位(11q13.3)相邻。3p24位于癌基因ERBA2区域内,且与癌基因RAF1相邻,11q13与癌基因INT2和SEA的位点重合。
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Dianci bileiqi, 2017 我国西北地区风害严重,直接威胁着区域输变电设备的运行安全。在详细调研新疆风害地区750kV变电站构架避雷针变形倾倒事故的基础上,分析了风害区域构架设备变形的原因:1)涡激振动导致避雷针的法兰螺栓断裂或者松动;2)避雷针的法兰焊接质量不合格,风力作用导致局部应力集中,从而产生局部裂纹;3)设备应力集中断裂为疲劳断裂,后期发展为脆性断裂。根据这些分析结果,提出了构架避雷针的抗风措施。
王建 +7 more
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Dianci bileiqi, 2000 从复合绝缘子端部应力分布、破坏过程和蠕变破坏及运行环境等方面 ,分析了复合绝缘子发生脆断的原因 ,提出了改进措施及工程应用中应注意的问题。指出在该地区转角杆塔 ...
郑春生, 杜正旺
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Dianci bileiqi, 2023 为研究分析某330 kV输电线路复合绝缘子断裂故障的原因，并对故障绝缘子同线路挂网运行复合绝缘子进行试验检测。通过宏观检查、断口分析、渗透检测等方法进行分析可知，此次断裂的主要原因是复合绝缘子在长期运行过程中产生原生宏观缺陷，导致外部环境中的腐蚀介质等进入芯棒部位，通过长期应力和腐蚀性介质作用，当芯棒剩余截面不足以承受重力载荷时，造成芯棒及外部硅橡胶撕裂，导致绝缘子断裂失效。最后，针对此类故障对运行中的绝缘子提出更换及跟踪的建议，以避免同类故障再次发生，确保电网安全运行。
张素慧 +8 more
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Preparation and Characterization of Chitosan-Sodium Hyaluronate-Probiotic Hydrogels and Its Sustained-Release Performance in Simulated Gastrointestinal Tract Conditions [PDF]
A physically cross-linked hydrogel was constructed by electrostatic interaction between chitosan (CS) and sodium hyaluronate (SH), and its texture properties, microstructure and functional properties were characterized.
LI Jiayi, WANG Honglei, LI Yajie, GUO Tingting, NI Yidan, ZHOU Quancheng, SHENG Guihua
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Study on stress evolution and damage fracture of cut blasting in high in-situ stress roadway [PDF]
In recent years, the mining state of mineral resources has changed from open air to underground and from shallow to deep. In the drilling and blasting construction of deep rock masses, in-situ stress has a significant impact on the blasting effect.
Chenxi DING +6 more
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Gaoya dianqi, 2013 针对某变电站GIS设备现场安装过程中发现某段导体回路电阻严重超标的问题,对GIS变电站内的导体进行现场解体,发现直线导体有裂纹。通过对该导体样品进行理化性能试验、断口宏观分析、金相分析、电镜及能谱分析等试验。结合该导体在安装过程中出现的状况,得出该直线导体开裂属于晶间解理脆性断裂,是由于厂家工艺粗糙、焊接工艺不良而导致。
仇炜
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Preparation and Property of Carbon Nanofibers-reinforced Sm2O3-added Epoxy Resin Neutron Shielding Material [PDF]
Small nuclear reactors have become one of the promising directions for the future development of advanced nuclear energy system due to its advantages of high safety, good economy, small-size flexibility, multi-purpose and modular construction.
ZHAI Yutao1, WANG Hongqing1, 2, HUANG Qunying1
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Jianzhu Gangjiegou Jinzhan, 2012 在美国北岭地震和日本阪神地震中钢框架节点的脆性破坏现象显示了传统节点抗震性能的弱点,国内外学者根据强柱弱梁原则,以塑性铰发生位置由原来的梁、柱连接处向距离柱截面一定距离转移为设计思想,提出钢框架新型断面削弱型节点,这种节点能够大大提高结构的抗震能力。对钢框架节点的破坏原因和节点构造做一个简单的介绍,具体阐述断面削弱型节点在延性、刚度和强度方面的研究以及断面削弱型节点在其它领域内的应用和发展做一个探讨。
宿专青, 殷福新, 张继涛
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Research progress on seal ring and gasket for pure hydrogen/hydrogen-enriched compressed natural gas pipeline [PDF]
Objective Seal rings and gaskets are deemed indispensable sealing components for the safe operation of pure hydrogen/ hydrogen-enriched compressed natural gas pipelines.
Cuiwei LIU +4 more
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