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191.
192.
Electrooptical Kerr effect has been studied in binary solutions of a dipolar liquid (-picoline, β-picoline) in a non-dipolar solvent (benzene, p-xylene) and 1,4-dioxane in the full range of concentrations of the dipolar component (0 ≤ f2 ≤ 1). The experimental Kerr constant Ks of the solutions, refraction index ns, density ρs and the dielectric constant εs have been measured and used for the calculation of the molar Kerr constants KSM within the Onsager local field model. Analysis of changes in the molar Kerr constants as a function of the solute concentration by fits of theoretical functions to the experimental ones has permitted a determination of the parameters characterizing intermolecular interactions in binary solutions. 相似文献
193.
This study presents the electromagnetic wave propagation through the frequency-dispersive and lossy double-negative slab embedded
between two different semi-infinite media. The double-negative slab is realized by using two models, the Lorentz and Drude
medium models. The properties and the required equations for the frequency-dispersive and lossy double-negative slab, the
Lorentz medium and Drude medium are given in detail. After the construction of the problem, the reflection and transmission
coefficients are derived for both TE and TM waves. Then, the reflected, transmitted and loss powers are determined using these
coefficients. Finally, in the numerical results, the mentioned powers for TE and TM waves are computed and illustrated as
a function of the incidence angle, the frequency and the slab thickness when the damping frequency changes. 相似文献
194.
Hongwei Yang Wanchun Tang Xiangkun Kong 《International Journal of Infrared and Millimeter Waves》2007,28(7):547-556
In this paper, shift operator finite-difference time-domain (SO-FDTD) method is applied for the calculation of the dispersive
medium. The high efficiency and accuracy of this method is verified by calculating the reflection of the plane electromagnetic
wave impinging on a non-magnetized plasma slab with different electron density distributions. The results show that the average
electron density only determines overall trends of the reflection, and different distributions affect the oscillating process
of the reflection. If the average electron density maintains the same, the distribution of electron density with homogenous
or inhomogeneous alternation will sharply take effects on the reflection. And magnitude of alternation of electron density
affects the incident frequency directly when the reflection tends to uniform. 相似文献
195.
3D FDTD Implementation for Scattering of Electric Anisotropic Dispersive Medium Using Recursive Convolution Method 总被引:1,自引:0,他引:1
Lixia Yang 《International Journal of Infrared and Millimeter Waves》2007,28(7):557-565
The finite-difference time-domain method based on recursive convoltion method (RC-FDTD) for the electric anisotropic dispersive
medium is discussed in detail. To exemplify the availability of the three-dimensional RC-FDTD algorithm, the backscattering
Radar-Cross-Section(RCS) of a non-magnetized plasma sphere is computed, and the numerical results are the same as the one
of the Shift Operater-FDTD method, and show that the RC-FDTD method is correct and efficient. In addition, the co-polarized
and cross-polarized backscattering time-domain of a magnetized plasma sphere are obtained by the RC-FDTD algorithm. The results
show that when the external magnetic field is implemented, the cross-polarized component appear, evidently. 相似文献
196.
Amphoteric refraction of light ray at the interface between isotropic materials and anisotropic materials is analyzed. Depending on the incident angle, the refractive light ray can either refract positively or negatively. This amphoteric refraction phenomenon can be quite prevalent when the difference of the two principal refractive indices is large. The reflectance under various incident angles has also been calculated, and an experimental demonstration with a calcite crystal in air is presented. 相似文献
197.
In this paper, 10 Gbps optical soliton transmission link using in-line semiconductor optical amplifiers (SOAs) for already installed standard single mode fibers (SMF) at 1.3 μm wavelength has been reported. The pattern effect and the impact of chirp on pulse propagation after amplification have been investigated. The observations are based on modeling and simulation optical soliton transmission link. Optical soliton pulse transmission over distances of the order of several hundreds of kilometers has been shown with and without initial chirp. 相似文献
198.
Room-temperature Ionic Liquids(ILs) have numerous unique properties that differ from those of conventional molecular solvents.Although the unique properties of ILs have been suggested to origin from their microscopic interionic interaction,detailed dynamics of interionic interaction of ILs has not been fully understood.Here,with the Femtosecond Optical Heterodyne-Detected Raman Induced Kerr Effect Spectroscopy(fs-OHD-RIKES),we measured the ultrafast dynamics of the interionic interaction of three typical im... 相似文献
199.
200.
The transformation from ferrihydrite to various iron oxides and iron oxyhydroxides has been given much attention not only in environmental science and geochemistry but also in biology and material science. This laboratory study attempted to investigate Fe(II)-induced transformation of ferrihydrite in sulfate-rich medium. The results indicate that the transformation in sulfate-rich medium differs from that in Cl− medium in the species, the amount and the morphology of products and transformation rate. Lepidocrocite is a main ingredient in the product in Cl− medium at room temperature (RT), while goethite is the only product in SO42− medium at RT. Goethite particles obtained in Cl− medium are star-like but rod-like in SO42− medium. The transformation rate in the latter medium is obviously slower than that in the former medium. The formation of lepidocrocite depends on both the ionic strength of the system and the dissolution rate of ferrihydrite. 相似文献