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21.
Optical Review - In this paper, we propose a full duplex architecture based on a hybrid link composed of free space optics (FSO) and multimode plastic optical fiber (MMPOF) for short-range wireless...  相似文献   
22.
Optical Review - In this paper, we report the performance evaluation of praseodymium doped fiber amplifier (PDFA) operating in 1.25–1.35 μm band of wavelengths based on...  相似文献   
23.
Spectral properties of some 2-Quinolones were investigate-ed. IR and 1H NMR were applied to characterize the ligands. The hydrogen bond property is of important parameter for controlling the behaviour of the compounds. The N[sbnd]H, O[sbnd]H, C[dbnd]O, C[sbnd]H, and C[sbnd]N fundamental functional groups are characterized. The electronic transitions are assigned. The data are explained on the basis of molecular structure and substituents effects. The acid-base equilibria and the phenomena of tautomerism for these compounds are explained and discussed. The acid exponents (pKOH, and pKNH) are evaluated.  相似文献   
24.
The aim of study was to evaluate the effectiveness of a new facility for recycling of plastics from granular waste electrical and electronic equipment. The installation consists of two sections, the products of a first tribo-aero-electrostatic separator being subsequently treated in two free-fall electrostatic separators. The tests were performed on a mixture of polycarbonate (PC) and polyamide (PA). Analysis of the purity of the products obtained was performed using a program of image processing in MATLAB. Products of very high purity (roughly 95% for both PC and PA) were obtained at a recovery rate higher than 70%.  相似文献   
25.
Abstract

The paper is essentially devoted to a quantitative comparison of the exact (1D) model developed in Part I, with two approximate models indicated by Kittel (1Da1) and by Van der Ziel (1Da2). And this is made for identical values of their common parameters. This allows to show that models 1D and 1Da1 generally present no suitable intervals for fitting. The model of Van der Ziel is more suited, for, a good fitting with the 1D model can be obtained, for relatively reduced G values, and for temperatures bounded upward by the characteristic temperature T 0 defined previously. The role played by the sub-models, obtained after simplifying the 1Dai model equations, is studied also.  相似文献   
26.
A computer simulation of the nonlinear Schrödinger equation is carried out to evaluate the impact of nonlinear susceptibility of a single mode fiber on the transmission of a soliton pulse. The third and fifth order nonlinear susceptibilities are considered in the simulation. The results show that the output soliton pulse shape strongly depends on the third order nonlinear susceptibility and gets distorted when the full width half maximum (FWHM) pulse width is of the order of 10ps or less.  相似文献   
27.
Inclusive production of ?0,K (892), andf is studied in \(\bar p\) p interactions at 12 GeV/c. The inclusive cross sections for ?0,K (892), andf are found to be 6.7±0.3 mb, 1.0±0.2 mb, and 1.4±0.3 mb, respectively. The differential cross sections are presented as a function of c.m. rapidity, Feynmanx and square of the transverse momentump T 2 . Comparison with the correspondingpp data shows some interesting differences which can be attributed to the \(\bar p\) p annihilation. The results are compared with the predictions of the quark fusion model.  相似文献   
28.
ABSTRACT

We measured the electric conductivity of large (25?×?50?mm) graphene films as a function of number of layers in the range of 1–20 layers. We also calculated the energy gap for such samples using density function theory. Our results showed a conductivity slightly above that of ITO for monolayer graphene and an exponential decrease as the number of graphene layers increased. Both experimental and simulation results showed a convergence of graphene into graphite at as little as 18–20 layers.  相似文献   
29.
The multiple lump solutions method is employed for the purpose of obtaining multiple soliton solutions for the generalized Bogoyavlensky-Konopelchenko(BK) equation. The solutions obtained contain first-order, second-order, and third-order wave solutions. At the critical point,the second-order derivative and Hessian matrix for only one point is investigated, and the lump solution has one maximum value. He's semi-inverse variational principle(SIVP) is also used for the generalized BK equation. Three major cases are studied, based on two different ansatzes using the SIVP. The physical phenomena of the multiple soliton solutions thus obtained are then analyzed and demonstrated in the figures below, using a selection of suitable parameter values.This method should prove extremely useful for further studies of attractive physical phenomena in the fields of heat transfer, fluid dynamics, etc.  相似文献   
30.
In this paper, we are interested in the derivation of macroscopic equations from kinetic ones using a moment method in a relativistic framework. More precisely, we establish the general form of moments that are compatible with the Lorentz invariance and derive a hierarchy of relativistic moment systems from a Boltzmann kinetic equation. The proof is based on the representation theory of Lie algebras. We then extend this derivation to the classical case and general families of moments that obey the Galilean invariance are also constructed. It is remarkable that the set of formal classical limits of the so-obtained relativistic moment systems is not identical to the set of classical moments quoted in Ref. 21 and one could use a new physically relevant criterion to derive suitable moment systems in the classical case. Finally, the ultra-relativistic limit is considered.  相似文献   
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