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131.
Taibi A. Ishak-Boushaki G. Medkour Idiri Z. 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(2):687-696
Journal of Radioanalytical and Nuclear Chemistry - True coincidence summing (TCS) correction factors were determined for 152Eu volume sources used for γ-ray efficiency calibration as the ratio... 相似文献
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133.
Ismail M. Nassar Aladin H. Kamel Diaa Khalil Omar A. Omar 《Optical and Quantum Electronics》2012,44(14):623-633
A planar lens structure based on an array of nanoscale slits in a metallic film is modeled using a waveguide modal technique. The structure is modeled as a one dimensional lens followed by free space propagation. The obtained results are compared to published experimental results as well as numerical simulations using either the finite difference frequency domain or the transmission line method. A good agreement has been obtained with significant simulation time reduction. 相似文献
134.
In this paper, we present an explicit realization of q-deformed Calogero-Vasiliev algebra whose generators are first-order q-difference operators related to the generalized discrete q-Hermite I polynomials recently introduced in [14]. Furthermore, we construct the wave functions and we determine the q-coherent states. 相似文献
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137.
Thin films of SnS were cathodically deposited onto stainless steel substrates from bath containing 0.025 M SnSO4, 0.25 M KSCN and 0.25 M Na2SO4. The mechanism of electrochemical co-deposition of tin and sulphur was investigated by cyclic voltammetry. Analysis of the
chronoamperometric current–time transients suggested that, in the potential range −560 to −590 mV vs saturated calomel electrode,
the electrodeposition of SnS involved progressive nucleation model. However, at a potential −600 mV, the electrodeposition
involved instantaneous nucleation model. The deposits have been characterized by scanning electron microscopy, X-ray diffraction
and optical measurements. SnS films were found to be polycrystalline with an optical energy gap of 1.38 eV. 相似文献
138.
139.
This work explores the application of digitalimage-processing techniques to the measurement of large plastic strains. Two
sample problems have been selected, namely the uniform tensile deformation of aluminum-sheet metal strips and the post-necking
deformation of copper circular rods. Images of these gridded metallic test pleces were captured, digitized and analyzed in
a fully computerized way to evaluate strain distributions, anisotropic parameters and plastic stress-strain flow curves. For
post-necked test pieces, Bridgman stress correction has been easily applied by defining the neck profile contour from the
automated processing of digitized images. Results compare satisfactorily with those based on displacements measured by conventional
microscopy. The presented technique, with added improvements, can consititute a viable one for accurate and fully computerized
measurement of large deformations. 相似文献
140.
Abdellatif Mamanou Fethi Khelfaoui Kamel Edinne Aiadi 《Optical and Quantum Electronics》2014,46(1):235-245
In this paper, a number of polymeric waveguide structures have been analyzed by using two distinct techniques which are: effective index method (EIM) and numerical simulation based on finite difference method (FDM). The main aim of this investigation is the calculation of effective indexes (EI) of the following structures: rib, ridge and buried channel waveguides at telecom wavelength $\lambda =1.55\,\upmu \hbox {m}$ for different dimensions of waveguide cores varying from 1.5–4 $\upmu \hbox {m}$ . Moreover, other optical propagation characteristics such as: confinement factor, normalized and propagation constant have been studied in TE polarisation. Otherwise the effect of the structure parameters and dimensions on the dispersion characteristics has been investigated. On the other hand, the optical field distribution has been computed using commercial software named OlympIOs. The polymers applied in the design of waveguide structures are the PVCi (n = 1,562 $\lambda = {1.55}\,\upmu $ m) used as core layer and the PMATRIFE (n = 1,409 $\lambda = 1.55\,\upmu $ m) used as substrate or cladding layer. The results obtained using EIM and simulation based on FDM show that effective index and field confinement factor of TE fundamental mode increase monotonously with the increasing dimension of core. The obtained results are in good agreement with published data based on other numerical methods. 相似文献