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排序方式: 共有59条查询结果,搜索用时 15 毫秒
1.
周航  屈绍波  彭卫东  王甲富  马华  张介秋  柏鹏  徐卓 《中国物理 B》2012,21(3):30301-030301
Based on the substrate integrated waveguide technology,we present a dual-band frequency selective surface(FSS) with a quasi-elliptic bandpass response.The characteristics of the quasi-elliptic bandpass response are realized by shunting two substrate integrated waveguide cavities of different sizes,with the same slots on both sides of the metal surfaces.Four cavities of different sizes and two slots of different sizes are used to design the novel FSS.Every bandpass response with sharp sidebands is induced by two transmission nulls that are generated by the coupling between the slot aperture resonance and the cavity resonance.The simulation results show that such dual-band FSS has the advantages of high selectivity and stable performance at different oblique incident angles.Moreover,it is easy to fabricate.  相似文献   
2.
<正>We simplify the material parameter equation for elliptical cylinder cloaks under transverse-electric and transverse-magnetic models,respectively,and confirm these simplified equations by numerical simulations.As a result,the number of the component parameters is reduced from three to two,which simplifies the design of meta-materials and thus opens up the possibility of achieving elliptical cylinder cloaks in an easy way.  相似文献   
3.
鲁磊  屈绍波  施宏宇  张安学  张介秋  马华 《物理学报》2013,62(15):158102-158102
设计、仿真并实验验证了基于宽边耦合螺旋结构的低频小型化超材料吸波体. 实验测试结果表明, 该超材料吸波体在1.39 GHz吸收率达到最大为98%, 其单元尺寸和总厚度均为6.8 mm, 约为1/32工作波长, 实现小型化窄带吸波. 由于吸波体中螺旋结构是旋转对称排列的, 因而其对垂直入射电磁波的极化方向是不敏感的. 此外, 该超材料吸波体对斜入射横电和横磁极化电磁波在60°时, 仍具有强吸收. 关键词: 超材料 吸波体 小型化  相似文献   
4.
The quantum tunneling effect (QTE) in a cavity-resonator-coupled (CRC) array was analytically and numerically investigated. The underlying mechanism was interpreted by treating electromagnetic waves as photons, and then was generalized to acoustic waves and matter waves. It is indicated that for the three kinds of waves, the QTE can be excited by cavity resonance in a CRC array, resulting in sub-wavelength transparency through the narrow splits between cavities. This opens up opportunities for designing new types of crystals based on CRC arrays, which may find potential applications such as quantum devices, micro-optic transmission, and acoustic manipulation.  相似文献   
5.
We verified experimentally left-handed metamaterials (LHM) composed of coplanar electric and magnetic resonators. A typical LHM sample composed of coplanar resonator unit cells was fabricated, investigated and tested. The experimental results show that the tested sample has a left-handed band of width 1.4 GHz in the X band. The experimental results agree quite well with the simulation ones. Moreover, both the simulation and experimental results show that the LHM under study can automatically achieve good impedance-matching in the left-handed band.  相似文献   
6.
陈春晖  屈绍波  王甲富  马华  王新华  徐卓 《中国物理 B》2011,20(3):34101-034101
A planar left-handed metamaterial(LHM) composed of electric resonator pairs is presented in this paper.Theoretical analysis,an equivalent circuit model and simulated results of a wedge sample show that this material exhibits a negative refraction pass-band around 9.6GHz under normal-incidence and is insensitive to a change in incidence angle.Furthermore,as the angle between the arm of the electric resonators and the strip connecting the arms increases,the frequency range of the pass-band shifts downwards.Consequently,this LHM guarantees a relatively stable torlerence of errors when it is practically fabricated.Moreover,it is a candidate for designing multi-band LHM through combining the resonator pairs with different angles.  相似文献   
7.
应用化学镀方法,以活化-敏化处理的活性炭作载体,制备高分散催化剂PtRu/C和PtRuSn/C. XRD、TEM及电化学测试表明,该催化剂Pt、Ru、Sn形成合金.金属颗粒的平均粒径约为3 nm. PtRu/C和PtRuSn/C二者对乙醇的阳极氧化都具有良好的催化活性和稳定性.  相似文献   
8.
一种基于线性同余算法的伪随机数产生器   总被引:11,自引:0,他引:11  
线性同余算法作为使用最为广泛的伪随机数产生算法,具有产生速度快、输出序列周期长等特点,但安全性能不佳的弱点始终制约着该算法在密码学领域的应用.本文在对线性同余算法详细分析的基础上,给出了一种不受乘数a选择限制的伪随机数产生器.该算法具有良好的伪随机性和安全性.  相似文献   
9.
二维光子晶体功率分配与合成的仿真   总被引:2,自引:2,他引:0  
王新华  王斌科  屈绍波  马华  徐卓 《光子学报》2009,38(6):1423-1426
利用平面波展开法,绘出了光子晶体的能带结构图,揭示了光子晶体能带结构的特点.在带隙结构中引入线缺陷,实现了对电磁波传播方向的控制.通过设计不同的线缺陷分布,实现了对电磁波传输能量的分配与合成.最终完成了对电磁波传播方向的控制和功率分配及合成的引导.采用Comsol Multiphysics软件对空气背景不同形状的介质光子晶体进行功率分配与合成的仿真,结果表明,在光子晶体中通过对线缺陷的设计,可实现功率的分配与合成.  相似文献   
10.
本文介绍调和级数发散至无穷的多种证明.  相似文献   
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