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11.
The simple closed-form model of nonlinear response of a high-temperature superconducting disk resonator on microwave power is proposed. The model is based on superconducting film nonlinearity and describes the dependence of unloaded quality factor on the incident power. The specified normalizing power is used as the only fitting parameter. Good quantitative agreement of modeled and measured data has been obtained. The results observed exhibit the kinetic nature of the nonlinearity of the disk resonator on an LaAlO3 substrate at T=60 K and more complicated, presumably thermal, heating nature of the nonlinearity at lower temperature 相似文献
12.
Metamaterials and their application in microwaves: A review 总被引:1,自引:0,他引:1
A metamaterial is a composite material that has attracted the attention of researchers since the late 1990s-early 2000s. This material contains an artificial periodic structure, which modifies its permittivity and permeability and, thereby, makes it possible to control the dispersion, refraction, and reflection of electromagnetic waves in the metamaterial. Analytical and experimental studies of the properties of metamaterials, as well as their applications, cover a wide frequency range from radio waves to the visible range. In recent years, considerable progress has been made toward the application of these materials in the microwave range (1–100 GHz). Works on development and application of metamaterials in the microwave range published over the last 8–10 years are reviewed. Artificial transmission lines as 1D metamaterials are discussed. Resonators, filters, and phase shifters based on the “metamaterial philosophy” are considered. Special attention is given to the application of metamaterials in the antenna technology. 相似文献
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In this paper we study the dispersion relation of thermal non-neutral plasma column by MHD theory. We use the dispersion relation to discuss the stability and dispersive properties in a non-neutral plasma-filled waveguide. The results are in agreement with those of cold non-neutral plasma. 相似文献
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Yuli YA. Gotlib 《Macromolecular Symposia》1999,146(1):81-87
The dynamic network model taken into account the friction relative to incompressible effective viscous medium (EVM), the hydrodynamic interactions of a network with the EVM, and the interchain friction is considered. Two collective network relaxation spectra (RS) arise. The first RS corresponds to the network motion relative to immobile EVM, the EVM does not take part in this motion. The second RS includes the combined viscous motion of the network and EVM because of long-range hydrodynamic interactions. This RS is finite and narrow for infinitely large network. The symmetry of this motion is in concordance with that of incompressible EVM. The existence of interchain friction leads to the narrowing of both types of relaxation spectra. 相似文献
18.
设k,n1和n2是3个正整数,G=(V1,V2;E)是一个二分图,使得|V1|=n1,|V2|=n2,其中n1≥2k+1,n2≥2k+1并且n1-n2≤1.如果对任意不相邻的x∈V1和y∈V2,都有d(x)+d(y)≥2k+2,则G包含k个相互独立的圈.以上结果部分地回答了Enomoto提出的关于二分图有独立圈的问题. 相似文献
19.
A. A. KURAEV M. P. NATAROV V. N. RODIONOVA V. N. SKRESANOV A. YA. SLEPYAN G. YA. SLEPYAN 《International Journal of Electronics》2013,100(5):1005-1014
Under investigation is a coupling element for coupling an open resonator to a rectangular waveguide and consisting of a smoothly irregular waveguide section conjugate to a narrow slot in a mirror, A technique for the determination of the coupling Q-factor is proposed and good agreement between calculations and experimental results is obtained. Based on such a coupling element, an open resonator has been well matched with a waveguide and made retunable in a wide frequency range without coupling adjustment.. 相似文献
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D. S. Kozlov M. A. Odit I. B. Vendik Young-Geun Roh Sangmo Cheon Chang-Won Lee 《Applied Physics A: Materials Science & Processing》2012,106(3):465-470
Tunable metamaterial operating in terahertz (THz) frequency range based on dielectric cubic particles with deposited conducting
resonant strip was investigated. The frequency of the first magnetic type Mie resonance depends on the electric length of
the strip. It can be changed under photoexcitation or applied voltage. This method of control was used for a design of tunable
double negative metamaterial based on dielectric resonant inclusions and wire medium. 相似文献