Results 11 to 20 of about 784,887 (166)
风云三号E星搭载的中能质子探测器实现了风云三号系列卫星首次对辐射带中能质子进行多方向的测量。中能质子探测器实现了对九个方向的测量能量范围为0.03~5 MeV的中能质子能谱的测量。为确定中能质子探测器的实际性能,在仪器交付前,利用中国科学院国家空间科学中心的中高能电子加速器,对中能质子探测器的能量分辨率,相对响应效率曲线、不同方向探头测量一致性以及抗电子污染能力进行了标定。文中介绍了仪器的标定场所、标定内容,并对标定的结果做了分析。其结果显示,仪器的能量分辨率为6.50%@310 keV ...
郝 梦坛 +9 more
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针对可移动非接触式月球表面电位探测器的电位无扰动测量单元对低能远焦电子束的需求,设计了低能远焦电子枪。以平板二极管电子枪为电子源,匹配两个静电聚焦透镜,将电子源引出的发散电子束聚焦为需要的形状,并加速至所需能量。优化电子枪的几何参数以及施加在电极上的电位,电子枪引出的电子束能量在5~500 eV内,并且具有良好的电子光路特性。电子束能量为5 eV时,初始半径r为5 mm,束腰至电子枪出口的距离p约为133 mm。随着能量增加,r逐渐减小至500 eV时的3 mm左右,p逐渐减小至105 mm ...
吴 伟 +4 more
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电缆质量直接影响电网运行的安全与稳定,为了更好地监管电缆质量,辨别优劣供应商,文中提出了一种基于熵权—层次分析融合的电力电缆质量评价方法,充分挖掘抽样检测等监管过程的大量数据,通过试验项目赋值权重和检测等级划分等手段,计算被检产品的质量加权分数,结合数理统计分析方法,实现对合格供应商的供货质量排序。选取了10家合格供应商的500份产品抽检报告,开展了质量分析排名。研究结果提示,该方法能够较好地区分不同合格供应商的质量水平,评价合格供应商产品质量的一致性和持续性 ...
熊汉武 +5 more
doaj
ABSTRACT Near‐infrared (NIR) phosphors with broadband and efficient emission are pivotal for the performance of NIR phosphor‐converted light emitting diodes (pc‐LEDs). In this study, the double perovskite phosphor La2MgTiO6:Cr3+ phosphor with broadband emission in the range of 650–950 nm was prepared.
Xu Qian +7 more
wiley +1 more source
Atom Probe Tomography‐Based Analysis of Residual Trace Elements in Advanced Metallic Materials
ABSTRACT Residual trace elements inherited from raw materials strongly influence the mechanical and environmental performance of advanced metallic alloys and recycling materials due to preferable boundary/interface segregation and resultant embrittlement effects, yet their parts per million level concentrations pose significant challenges to ...
Congcong Li +17 more
wiley +1 more source
雷击是引发配电网故障的主要原因之一,可靠有效辨识雷击故障性质对配电线路防雷设计评估和采取针对性防雷措施有重要意义。本研究提出雷击配电线路电流能量溯源的原理,利用Prony算法对检测到的线路电流信号进行模式分解,分离出静电感应能量成分和电磁感应能量成分,根据不同雷击性质时能量成分占比不同的特征,对直击雷故障与感应雷故障进行辨识。通过MATLAB与ATP-EMTP联机的仿真测试,结果表明该方法能可靠有效的判别雷击故障性质。
肖麟祥 +4 more
doaj
ABSTRACT NiTi shape memory alloys (SMAs) show excellent performance in vibration damping and corrosion resistance. However, due to low hardness and lack of self‐lubrication, they suffer severe friction and wear during service. Although various strategies including doping and heterostructure design have been proposed, the effects are unsatisfactory.
Huwen Ma +13 more
wiley +1 more source
当前中国和其他国家的电力市场再一次面临着深刻变革,传统的电力市场理论受到挑战。本文对新背景下的电能商品品质衡量及定价机制问题进行了初步探讨。作为理论研究的基础,首先剖析了电力市场/电力系统组成的大规模复杂系统中电力系统物理层、商品交易层和金融交易层这3个层次问题的区别与联系。提出从波动性、易控性、随机性3个维度对电能商品品质进行衡量,并在功率数值的基础上加入时间维度形成由功率—时间对组成的连续时间电能商品模型以反映不同的商品品质,并基于泛函极值优化理论发展出基于连续时间商品模型的电力市场理论 ...
陈皓勇, 李立浧
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ABSTRACT The development of lightweight, high‐attenuation, and broadband carbon‐based electromagnetic wave absorbers is hindered by the intrinsic trade‐off between impedance matching and dielectric dissipation. Herein, we report a facile and scalable synthesis of N‐doped lignin‐derived interconnected porous carbon (Nx‐LIPC) via hydrogen‐bond self ...
Bin‐Peng Zhang +7 more
wiley +1 more source
ABSTRACT Dielectric polymers commonly suffer from severe performance degradation above 150°C, hindering advanced power systems. Herein, we demonstrate a polyetherimide (PEI) nanocomposite that overcomes this by mimicking the gradient architecture of nacre and bamboo, incorporating a continuous vertical gradient of fluorinated boron nitride nanosheets ...
Jian Wang +8 more
wiley +1 more source

