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1.
Seventeen alkylated salicylidene-o-aminophenol derivatives were tested as fluorimetric reagents for aluminium, gallium, indium, scandium and beryllium. The aluminium, gallium and beryllium complexes are intensely fluorescent, and the scandium and indium complexes weakly fluorescent. The fluorescence properties of the aluminium, gallium and beryllium complexes were studied and conditions for the fluorimetric determination of these metals were established. 2-Hydroxy-4-methylaniline-N-2-hydroxy-4-methyl-benzylidene is a good reagent because of the reproducibility and sensitivity of the fluorescence. The optimal ranges for determination are 0.005–3 mg Al/25 ml, 0.1–7 μg Ga/25 ml and 0.02–7 μg Be/25 ml. In all cases, 1:1 metal—ligand complexes are formed. Optimal reaction conditions and interference studies are reported. 相似文献
2.
Dan Zhang Hongting Jia Kiyotoshi Yasumoto 《International Journal of Infrared and Millimeter Waves》2008,29(9):823-831
A problem of coupling between conventional dielectric waveguides and a two-dimensional photonic crystal waveguide is analyzed,
using the Fourier series expansion method combined with the absorbing boundary condition of a perfectly matched layer (PML).
A novel structure for the input and output ends of the photonic crystal waveguide is proposed to increase the coupling efficiency.
Numerical examples are demonstrated and discussed to validate the effectiveness of the proposed structure. 相似文献
3.
Vakhtang Jandieri Kiyotoshi Yasumoto Hongting Jia 《International Journal of Infrared and Millimeter Waves》2006,27(2):301-317
Electromagnetic scattering from two-dimensional photonic crystals with two-dimensionally periodic defects is analyzed using
a model of multilayered periodic arrays of parallel circular cylinders. The reflectance of the photonic crystals of finite
thickness, which are free-standing or embedded in a dielectric slab, is obtained in terms of the lattice-sums, the T-matrix
of a circular cylinder, and the generalized reflection matrix for a layered system. Numerical examples demonstrate that the
refection and transmission bands of the crystals are reformed by introducing the periodic defects and their band natures are
very sensitive to the polarization of excitation and the relative position of the defect element within a unit cell. 相似文献
4.
Faik Bogdanov Guram Kevanishvili George Jandieri Kiyotoshi Yasumoto Dong Kim III 《International Journal of Infrared and Millimeter Waves》2006,27(10):1347-1364
A rigorous electromagnetic theory is developed to analyze multiport waveguide junctions with artificial inclusions formed
of the conducting strips and dielectric layers. The method is based on the Fourier transform technique combined with the mode
matching method technique that takes into account the edge conditions in vicinity of the strip edges. The scattering characteristics
of a 3-port junction are discussed with the numerical examples for the SWR maps, the power reflection and transmission coefficients,
and the 2D plots of near fields distributions inside the junction area. A strategy of optimize matching properties of the
3-port waveguide junctions is also presented. 相似文献
5.
Vakhtang Jandieri Kiyotoshi Yasumoto Hiroshi Toyama 《International Journal of Infrared and Millimeter Waves》2007,28(12):1161-1173
A novel formulation of radiation from a localized line source placed in two-dimensional photonic crystals consisting of layered
periodic arrays of parallel circular cylinders is presented. The method employs the spectral domain approach. The spectral
response of the photonic crystals to the line source excitation is calculated using the lattice sums, the T-matrix of a circular
cylinder, and the generalized reflection and transmission matrices of the layered system. The far-zone radiated field is obtained
using the conventional asymptotic method to the spectral response. The radiation patterns of the localized line source sandwiched
by two photonic crystals are numerically studied. 相似文献
6.
Yongmei Pan Shanjia Xu Kiyotoshi Yasumoto 《International Journal of Infrared and Millimeter Waves》2005,26(2):189-200
Loss and dispersion characteristics of groove guide are two practically important factors in the design for millimeter wave system consisting of groove guide. In this paper, a new method is presented for analyzing loss and dispersion characteristics of the groove guides with arbitrary groove cross-sections. The method is based on the combination of an equivalent active transmission line equation and the staircase approximation. Numerical results of dispersion and attenuation properties for some groove guides with different groove profiles are given. The effectiveness and practicality of the present analysis are confirmed by the data given in the literature.*Supported by the National Natural Science Foundation of China (No. 60171019)
and (No. 60371010) 相似文献
7.
Mode Matching Analysis of Propagation Characteristics for Dielectric Ridge Guide with Triangular and Trapezoidal Profiles* 总被引:1,自引:0,他引:1
Yuanzhi Lin Shanjia Xu Kiyotoshi Yasumoto 《International Journal of Infrared and Millimeter Waves》2005,26(2):173-188
Leaky characteristics of dielectric ridge guide with triangular and trapezoidal cross section are analyzed by a method that combines the mode matching procedure with the staircase approximation and multimode microwave network theory. Our emphasis in this paper is on the parametric effects of cross section profile on leakage and propagation properties of the ridge guide. Some numeral results with their explanations are given for practical reference.*Supported by the National Natural Science Foundation of China (No. 60171019)
and (No. 60371010) 相似文献
8.
A semi-analytical approach for a periodic planar array formed by a finite number of circular cylinders is presented using a model of layered cylindrical arrays. The method consists in extracting the reflection and transmission matrices of a cylindrically periodic array of circular cylinders and then obtaining the characteristics of layered structures by using a recursive formula. 相似文献
9.
Hongting Jia Kiyotoshi Yasumoto 《International Journal of Infrared and Millimeter Waves》2004,25(11):1591-1609
A new formula has been proposed for analyzing arbitrary shaped-gratings. The formula is in very simple form, is always suitable for all the gratings of arbitrary profiles, any depth, and any permittivity. The new formula has a character of satisfying rigorously the energy-flux conservation. The effectiveness and its characters have been confirmed by numerical examples. The numerical examples have shown that the new formula is superior to the classical formulas with Fourier series technique in convergence, computing precision, and stability. 相似文献
10.