Results 31 to 40 of about 53,872 (143)
在中国西北的一些高海拔地区,低温持续时间较长,硅橡胶性能改变而引起沿面闪络电压的变化对电力系统有很大影响,因此,研究低温环境对硅橡胶绝缘材料沿面闪络电压的影响以及低温下硅橡胶绝缘材料的闪络电压随温度变化的规律,了解低温下硅橡胶性能改变是否是造成绝缘子闪络事故的原因具有重要意义。为此,在低温下采用恒温试验箱对复合绝缘子用硅橡胶材料进行了低温冷冻处理,在不同温度的低温条件下采用平头板电极模拟不均匀电场,对不同Al(OH)3含量的硅橡胶试样进行了沿面闪络电压的测定。实验结果表明:随着温度的降低 ...
邢照亮 +7 more
doaj
ABSTRACT The limited crack resistance of coarse grain boundaries and coarse interfaces leads to an incompatibility between high‐temperature strength and ductility in TiAl alloys. Tailoring stress‐oriented textures and multiscale heterogeneous interfaces can effectively impede crack propagation, thereby overcoming this trade‐off.
Kexuan Li +7 more
wiley +1 more source
ABSTRACT In Co‐based alloys, the γ phase is normally stable at high temperatures and the ε phase at low temperatures, and there is a martensitic transition on cooling to ∼417°C. In the γ/β dual‐phase CoCrAlY bond coat of turbine blade thermal barrier coating systems, we observed the opposite: γ remained stable at room temperature, yet it underwent a γ →
Junkai Liu +8 more
wiley +1 more source
ABSTRACT Fast‐charging capability is one of the crucial factors determining the application prospects of sodium‐ion batteries (SIBs). Nevertheless, the mismatched sodium storage kinetics and Coulombic efficiency (CE) in hard carbon anodes are bottlenecks in the implementation of fast‐charging SIBs. Herein, we propose a facile pre‐carbonization strategy
Qixin Liu +8 more
wiley +1 more source
Magnetization Dynamics Control for Noise Reduction in Fluxgate Sensors
ABSTRACT Fluxgate sensors are indispensable for the detection of weak magnetic fields. However, their noise performance remains constrained by an incomplete understanding of the interplay between the high‐frequency magnetization dynamics of the core material and the overall sensor behavior.
Chunyang Mu +11 more
wiley +1 more source
针对冬季温度低导致的脱氮效率下降问题,建立上流式固定床生物膜反应器(UFBR),并与传统活性污泥反应器(SASR)低温时的反硝化效果、微生物特性及群落结构进行比较,分析低温下生物膜的形成。经过160 d先逐步降温再提升硝酸盐进水负荷(NLR)的连续运行,UFBR表现出耐受低温能力强、脱氮效果优于SASR的特点;8℃下,UFBR的硝酸盐去除负荷(NRR)达到0.32 kg/(m3·d),比SASR高2倍多。低温下活性污泥产生大量胞外聚合物,发生污泥膨胀。而UFBR生物膜可分泌更多蛋白质 ...
赵楠楠 +5 more
doaj +2 more sources
ABSTRACT Gradient structures (GS) introduced by plastic deformation have been shown to effectively enhance the surface properties of metallic materials. However, the GS fabricated by existing methods often suffers from limited hardening depth and limited control over the GS layer, which constrain their engineering applications.
Yansong Guo +5 more
wiley +1 more source
随着特高压交流工程建设的不断开展,越来越多特高压变电站将建设在低温地区。由于特高压开关设备普遍采用SF6气体绝缘,在低温地区使用会存在低温液化问题,降低设备运行稳定性,提升电网运行风险,需采取措施提高设备耐受低温能力。基于设备重要性的考虑,对于1 100 kV GIS,宜采用户内布置方式。对于户外使用的1 100 kV出线套管和分支母线可采用降低气压的方法降低气体液化温度。对于其他电压等级的GIS设备,可在设备外壳加装加热装置,按一定程序对设备气室加热,保证绝缘和灭弧介质SF6的状态稳定 ...
刘焱 +5 more
doaj
ABSTRACT Infrared (IR) stealth is crucial for improving the survivability of equipment. The growing demand for service in marine environments poses new challenges to the composition and structural design of existing IR stealth coatings. This study first investigates the effects of NaCl/water vapor corrosion on the IR stealth performance of GH3536 and a
Kang Wang +5 more
wiley +1 more source
Microstructure Tailoring of Laser Powder Bed Fused Nb521 Alloy Toward Strength‐Ductility Synergy
ABSTRACT Niobium‐based refractory alloys are promising candidates for high‐temperature aerospace structures, yet their limited ambient‐temperature ductility and poor processability remain major barriers to broader implementation. Here, Nb521 alloy was fabricated by laser powder bed fusion (LPBF), and the effects of processing conditions and subsequent ...
Lele Qin +7 more
wiley +1 more source

