Results 21 to 30 of about 9,791 (121)
ABSTRACT High‐entropy oxides (HEOs) are promising for microwave absorption but suffer from a trade‐off between impedance matching and attenuation, often requiring high filling ratios (> 50 wt%). Herein, we propose a “lattice‐spin” dual‐regulation strategy by introducing giant‐radius Bi into a single‐phase HEO solid solution.
Junwei Zhang +11 more
wiley +1 more source
ABSTRACT Electromagnetic wave absorption materials require high dielectric loss and excellent impedance matching performance. However, current conventional biomass‐derived electromagnetic wave absorption materials are still limited by low electrical conductivity and a single structure.
Yue Zhang +9 more
wiley +1 more source
ABSTRACT To address the demand for high‐temperature stability, broadband strong absorption, and multifunctional integration of electromagnetic wave absorbing materials in complex service environments, lightweight molybdenum disulfide (MoS2) decorated silicon carbide (SiC) nanofiber composite aerogels with a directional layered interconnected structure ...
Zhi Song +4 more
wiley +1 more source
研究了放电声发射波检测中用小波分析进行信号提纯与消噪的实现问题,包括选择小波、选择小波分解层数、提取有用频段的小波系数、小波消噪过程、小波消噪中的阈值选取,以及对提纯的放电声发射波进行小波消噪等。两组实测信号的小波提纯与消噪结果证明了信号提纯与消噪的优越性。
王成江, 舒乃秋
doaj
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
母小波的选择对提取绝缘子泄漏电流中的突变成分具有重要作用。根据对大量泄漏电流信号的分析,得出小波分解后的细节的能量越集中,所采用的母小波越适合提取泄漏电流的突变成分。据此采用熵作为评价母小波优劣的方法,并给出了泄漏电流熵的计算过程,进而给出了选择最佳母小波的步骤。以高压试验室采集到的泄漏电流为分析对象,以db(Daubechies)小波系为待选母小波集合,根据各小波分解泄漏电流之后的熵值,确定了db2小波为最佳母小波。采用不同母小波对泄漏电流进行了分析,结果显示db2小波优于其他小波。从而得出结论 ...
黄建才, 朱永利
doaj
ABSTRACT The growing deployment of high‐frequency electronic systems has intensified the demand for high‐performance microwave absorption materials. In this work, we developed La‐V co‐substituted barium hexaferrites, Ba1‐xLaxFe11.9V0.1O19 (BLFVO), via a sol‐gel route.
Zhihui Yang +7 more
wiley +1 more source
选取几种不同的小波函数利用连续小波变换(CWT)对同一图像进行处理,比较不同小波函数的小波脊系数幅值信息和恢复图像的效果,得出可以参考小波脊系数幅值表现的方法来选取合适的小波函数的结论.计算机模拟和实验也证实了该方法的正确性.
许罗鹏, 陈文静, 赵玥, 蔡义祥
doaj
ABSTRACT Because magnetic permeability is an intrinsic property of materials, achieving the regulation of magnetic loss is one of the challenges for electromagnetic wave absorption materials. This paper focuses on the research idea of in situ growth of dispersed nanocrystalline FeSiB in an amorphous FeSiB matrix to regulate magnetic properties.
Lei Wang +4 more
wiley +1 more source
介绍了二进小波变换的基本原理及其滤波特征,采用二进小波函数对变压器中含强载波干扰的局放信号进行了小波变换。仿真结果表明,二进小波变换能消除强载波干扰,能准确地检测出局放脉冲信号的幅值及其发生的时刻。
李祥飞, 邹恩, 邹莉华
doaj

