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991.
二维表面浮雕结构的矢量衍射分析   总被引:10,自引:0,他引:10  
利用等效介质理论,通过严格的耦合波理论计算和分析了二维表面浮雕结构的反射效率与各种因素的关系,给出了不同情况下的变化曲线;同时计算出了该结构在正入射情况下的等效折射率系数。明确提出:不管是对称的还是非对称的二维表面浮雕结构,方位角和极化角的变化对其反射率的影响都不明显;从而得出二维表了雕结构可以实现消偏振、减反的特性。分析了该结构的带宽限制,给出了在给定结构下受限的带宽;同时对浮雕高度加工误差对反射率的影响作了分析,对实际工作有一定的指导意义。  相似文献   
992.
In this Letter, we propose to use the Cantor-type cylindrical-coordinate method in order to investigate a family of local fractional differential operators on Cantor sets. Some testing examples are given to illustrate the capability of the proposed method for the heat-conduction equation on a Cantor set and the damped wave equation in fractal strings. It is seen to be a powerful tool to convert differential equations on Cantor sets from Cantorian-coordinate systems to Cantor-type cylindrical-coordinate systems.  相似文献   
993.
Xin Li  Henk F. Arnoldus 《Physics letters. A》2013,377(34-36):2235-2238
Reflection and transmission of traveling and evanescent waves by a layer of material with a negative index of refraction (NIM) is studied by means of the Fresnel coefficients. We derive their values in the “NIM limit”, and we show that this limit is consistent with the exact solution. It is also indicated that simply substituting the negative values of the relative permittivity and permeability of the NIM material into the exact solution leads to incorrect results for evanescent waves.  相似文献   
994.
995.
Emission spectra from plasma arc welds were observed under a variety of current, voltage, polarity, and standoffs. If reverse polarity (welding torch positive) welds are struck below 50 amperes most of the power is deposited at the electrode rather than the workpiece because of low carrier density within the arc. Straight polarity, on the other hand, suffers no such limitation because of electrons created in the pilot arc used to start the weld process.  相似文献   
996.
The complexes of Ni (His) 2·H2O, Ni (Gly) 2·2H2O, Pd (His)Cl2·H2O and Pd(Gly) 2·2H2O were synthesized. And the IR, electronic absorption and photoacoustic spectra of these complexes were measured in solid state. The nature of the metal-carboxylate coordinate bond were deduced from the variation in the carboxyl stretching frequencies. And the d-d transition absorptions of these complexes were interpreted quantitatively with the 3d scaling radial theory. Therefore, the structural characterizations were also discussed with their spectral behaviors.  相似文献   
997.
Cu(L-glu)(bpy)(L-glu = L-glutamato; bpy = 2, 2′-bipyridine) was prepared. Its electronic absorption spectrum and photoacoustic spectrum were recorded at room temperature. They were compared with each other and compared quantitatively with ligand field theory(LFT) and the radical wave function of non-free ions[1–3]. Therefore, the electronic structure was also investigated with its spectrum behaviors and PLFT[1–3].  相似文献   
998.
A molecular dynamics (MD) simulation is employed to study the phase transition process in argon induced by shock wave transmission. Deriving the relation between the shock and piston velocities, the theoretical equation of state for argon is presented. Also, argon equation of state is obtained by measuring the quantities directly from simulations to be able to detect the phase transitions. The phase transition is also detected by using argon phase diagram and free energy calculations. A comparison shows good agreement between the theoretical and MD results for the phase transitions. Based on these simulations, it is concluded that under a shock wave transmission with suitable energy, the solid argon experiences a phase transition from solid to liquid and another from liquid to supercritical fluid. By reflecting the shock wave back at the end of its passage, the whole argon may reach the supercritical state.  相似文献   
999.
    
In this work,we investigated the existence of compacton-like configuration in the O(3)-sigma model. We consider a minimally coupled O(3)-sigma model with a gauge field governed by a generalized Chern-Simons (CS) term. Contrary to that established in the literature,we impose a new set of boundary conditions and we find solutions to the variable fields and the respective energy density in the Bogomol'nyi limit. On the other hand,the introduction of a parameter ω in the Chern-Simons term can be adjusted to lead to finite-energy solutions of the model. Moreover,compact-like structures were studied with the evolution of this ω-generalized Chern-Simons term.https://doi.org/10.1209/0295-5075/130/10005  相似文献   
1000.
    
Relativistic arbitrary spin Hamiltonians are shown to obey the algebraic structure of supersymmetric quantum system if their odd and even parts commute. This condition is identical to that required for the exactness of the Foldy-Wouthuysen transformation. Applied to a massive charged spin-1 particle in a constant magnetic field,supersymmetric quantum mechanics necessarily requires a gyromagnetic factor g=2.https://doi.org/10.1209/0295-5075/130/30003  相似文献   
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