Results 1 to 10 of about 2,194 (115)
Kongjian kexue xuebao, 2023 全球主磁场模型描述了主磁场的时空分布特征。模型的主磁场阶数是构建主磁场模型的关键问题之一。使用贝叶斯推理分析全球主磁场模型，依据贝叶斯证据比较模型阶数，为主磁场的阶数分析提供一种统计依据。利用Swarm卫星磁测数据，估计不同阶数的主磁场模型的证据。结果表明，在1~20的模型阶数中，阶数N = 12具有全局最佳证据。参照Jefrrey’s scale的阈值区间，数据对阶数N = 12的偏好显著优于其他阶数。实验表明，主磁场阶数的证据推理可用于研究主磁场贡献，结果与14阶球谐函数的功率谱分析相匹配。
马 森 +3 more
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Gaoya dianqi, 2021 真空灭弧室的灭弧性能与真空灭弧室触头的磁场特性密切相关,其中纵向磁场(AMF)灭弧技术与横向磁场(TMF)灭弧技术应用最为普遍。基于人工零点的高压直流真空断路器,引入高频震荡电流帮助开断,为了分析真空断路器开断高频电流情况下的磁场特性,文中建立了两种类型的触头结构进行有限元仿真,对比分析真空灭弧室磁场特性以及触头片涡流情况。结果表明:在高频电流开断情况下,横磁结构触头与纵磁结构触头相比有更好的磁场特性分布;触头片涡流是影响纵磁结构触头磁场特性恶劣的关键因素,而对横磁触头间隙磁场特性几乎没有影响。
李如春 +4 more
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Gaoya dianqi, 2023 换流站内复杂电磁环境会对电力设备在线监测装置测量结果产生不利影响，为了提高装置测量结果的稳定性和可靠性，有必要对换流站设备附近区域的电磁场进行测量并分析其分布规律。文中利用电磁场分析仪对4所±500 kV换流站变压器、高抗、避雷器、电压互感器等附近的工频电场、磁场进行了测量。测量结果表明：所有被测换流站75%以上测点的电场强度分布在0～15 k V/m，最大值出现在避雷器附近，为32.6 kV/m；约90%测点的磁感应强度分布在0～80μT，最大值出现在换流变附近，为0.26 mT。基于实测结果 ...
贺家慧 +4 more
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Gaoya dianqi, 2022 针对因真空断路器大电流故障开断过程中灭弧室断口场域磁感应强度弱，导致磁场对电弧等离子体有效控制力减弱的问题，将NSPSO多目标优化方法与磁场有限元分析相结合，以12 kV/1 250 A/31.5 kA典型技术参数的中压真空断路器灭弧室纵磁触头系统为对象进行结构优化设计，以触头片开槽长度、斜槽深度、触头片开槽偏转角、触头杯座厚度为优化设计变量，以灭弧室断口中心截面纵磁最大值与磁场有效作用面积同时达到最大值为优化设计目标，求得Pareto前沿非支配优化解集 ...
臧谦 +6 more
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Magnetization Dynamics Control for Noise Reduction in Fluxgate Sensors
Rare Metals, Volume 45, Issue 8, August 2026.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
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Enhanced Magnetocaloric Effect in Tb‐Co‐Ni Magnets via Chemical Pressure
Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT Magnetic refrigeration materials are significantly needed in versatile modern industries, including scientific research, aerospace, and health care, due to their potential applications in gas liquefaction and storage. Herein, a significantly enhanced magnetocaloric effect with a suitable operation temperature range of 53–114 K and a giant ...
Lei Xi +11 more
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Dianci bileiqi, 2021 为了更加高效合理进行变电站接地网腐蚀状态诊断,在现有借助地毯式探测接地网地表磁场强度进而分析接地网状态研究的基础上,提出一种结合磁场延拓技术应用于接地网腐蚀状态的研究方法。依据矢量格林恒等式,可知大平面边界各点磁场矢量积分关系,进而计算出平面内测量磁场与未知磁场的积分关系,通过剖分离散构建线性方程组,可求出未知磁场强度,达到磁场延拓的目的,即只需要测量接地网地表的部分磁场强度,就可以延拓重构得到整个接地网地表区域的磁场强度,进而为接地网故障诊断提供判据。采用该技术可以大大减少磁场强度的测量工作 ...
李柯
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Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT The composition and structural characteristics of metacomposites are crucial for tuning their negative electromagnetic parameters; however, the lack of a clear structure–property relationship severely limits their application in dielectric and magnetic fields.
Chunyuan Deng +9 more
wiley +1 more source
Dizhen xuebao四川长宁地区平均点距间隔2 km的952个测点测得的岩石圈磁场空间分布结果显示，长宁背斜内东西部存在显著的磁场分布差异，且该差异可能与地震活动区域相关，例如：背斜内部对应岩石圈磁场正值区域，背斜边界对应负值区域；背斜的西北边界区域对应最显著的岩石圈磁场负值，背斜东北侧以岩石圈磁场正值分布为主，背斜南侧以岩石圈磁场负值为主。基于上述岩石圈磁场数据，我们构建了区域磁偶极子反演的技术途径以开展磁偶极子源的反演研究。具体途径为：将化极后的长宁背斜岩石圈磁场进行快速傅里叶变换 ...
Xiaotao Wu, Bin Chen, Chao Dong
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Structural Modulation of Magnetic Softness in Fe‐Based Amorphous Alloys via Pulse Current Training
Rare Metals, Volume 45, Issue 6, June 2026.ABSTRACT Fe‐based amorphous alloys, despite their intrinsically low magnetocrystalline anisotropy, suffer from quasi‐dislocation dipoles and localized stress fields that impede domain‐wall motion and increase coercivity. Here, we introduce pulse current training (PCT) as an energy‐efficient technique to overcome these limitations in a Fe76Si9B10P5 ...
Shumin Ye +13 more
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