Results 21 to 30 of about 13,964 (117)
Read the free Plain Language Summary for this article on the Journal blog. Abstract Oxygen supply capacity (α) is a physiological trait hypothesized to shape the metabolic niche and biogeography of aquatic breathers, yet how natural selection targets α remains unclear.
Na Zhang +6 more
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变压器绝缘性能试验能有效判断变压器是否存在整体受潮、部件表面受潮及贯穿性缺陷,是变压器能否投入运行的重要依据。文中在用于高压高阻测量的惠斯通电桥基础上,研究一种电力变压器绝缘电阻的测量方法,利用模糊PID控制器较好的的跟踪能力及响应速度调节电桥平衡,再根据平衡公式准确算出变压器绝缘电阻值。在用扩展德拜模型模拟等效变压器绝缘电阻基础上,建立测量系统的仿真模型,实验结果也与计算结果相一致,从而验证了该方法的可行性。
刘恒, 陈文鸿, 沈剑韬, 何益宏
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十字形部分包覆钢-混凝土组合柱轴压性能数值分析与承载力计算方法
为研究十字形部分包覆钢-混凝土组合柱(PEC柱)轴向荷载作用下的受力性能,通过有限元软件ABAQUS建立了足尺十字形PEC柱模型,并利用已有的试验数据验证了其可靠性;在此基础上,进行了典型十字形PEC柱轴压全过程受力分析,揭示了其在轴压作用下的受力机理和破坏模式,并对该构件进行了受力性能参数分析,系统分析了含钢率、截面高宽比、钢材强度、混凝土强度、系杆间距和截面面积等参数对其轴压性能的影响规律。研究结果表明:十字形PEC柱受力性能良好,其破坏模式主要表现为柱中部混凝土被压碎,钢筋骨架向外发生鼓曲 ...
王静峰 +4 more
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ABSTRACT The use of Ti6Al4V alloy in dental implantation is constrained by its high elastic modulus and biological inertness, which lead to delayed osseointegration and a high failure risk. Additionally, its chemical incompatibility with hydroxyapatite (HA) impedes the development of stable bioactive composites.
Shangyong Zuo +8 more
wiley +1 more source
为研究"V"形串中复合绝缘子长期运行受压对绝缘子性能的影响,进行了"V"形串复合绝缘子的受力试验。监测了角度偏移、受压复合绝缘子的应力及水平荷载和垂直荷载,并在多次试验后对受压绝缘子进行了机械破坏负荷试验。结果表明,在"V"形串中复合绝缘子受压并不影响其机械性能,但应注意频繁弯曲是否会造成密封破坏。
沈鼎申, 蔡炜, 王劲
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Inverse Thermal Softening Behavior in a High‐Entropy Alloy Under Various Strain Rates
ABSTRACT Although face‐centered cubic high‐entropy alloys (HEAs) have received extensive attention and in‐depth research, most existing studies focus on single temperature or strain rate conditions, lacking systematic investigations into deformation mechanisms under extreme thermomechanical coupling environments.
Zhi Wang +6 more
wiley +1 more source
ABSTRACT Lung cancer remains a major cause of cancer‐related mortality worldwide, and non‐small cell lung cancer (NSCLC) accounts for the largest proportion of diagnosed lung cancer cases. Exosomal programmed death‐ligand 1 (PD‐L1) has attracted increasing attention as a potential liquid‐biopsy biomarker associated with tumor immune regulation; however,
Chen Su +6 more
wiley +1 more source
测试避雷器或电阻片的直流参考电压在承受大电流或方波冲击试验前后的变化率比测试其残压变化率更能判断该避雷器或电阻片受冲击后的电性能退化程度;建议修改GB11032-2000中的直流参考电压、残压要求;建议提高和完善对低压避雷器的特性要求。
杨凤金, 卢振亚, 李政文
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Boosting Decomposition and Combustion of TKX‐50 and HTPB/TKX‐50 Propellants With NH2‐MIL‐88B(Fe) MOF
ABSTRACT Dihydroxylammonium 5,5′‐bistetrazole‐1,1′‐diolate (TKX‐50) is a promising energetic material that possesses both exceptional energy density and low sensitivity. Nevertheless, its application is hindered by incomplete pyrolysis during combustion or explosion. Various strategies, including eutectic formation, composite preparation, and catalysis,
Jingwen Chen +10 more
wiley +1 more source
针对现行部分组合钢-混凝土构件中系杆易于脱落的问题,提出两种系杆改进形式,设计了4根梁试件进行试验研究,考察纯弯与剪弯受力状态下梁的性能表现。试验结果表明:X型与C型系杆均能较好地拉结受压翼缘,受压翼缘在弹性段内没有屈曲;采用了这两种系杆的试件承载能力基本一致;与C型系杆相比,X型系杆对混凝土的约束作用更强,混凝土整体性更好,并且能抑制斜裂缝;纯弯试件与剪弯试件破坏部位的现象主要以混凝土的压溃、受压翼缘屈曲为主,剪弯试件破坏部位还观察到了受拉翼缘的开裂。此外 ...
李炜, 陈以一
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