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51.
Two-Layered Poly-o-phenylenediamine/Polyaniline Composite: Electrosynthesis and Spectroelectrochemical Properties 总被引:1,自引:0,他引:1
E. Yu. Pisarevskaya E. V. Ovsyannikova N. M. Alpatova 《Russian Journal of Electrochemistry》2004,40(9):969-976
Spectroelectrochemical properties of poly-o-phenylenediamine (PPD) and the synthesized composite of PPD and polyaniline—two chemically related polymers containing an amino-substituted benzene ring but having different conduction nature—are studied. The polyaniline synthesis on PPD-modified electrodes involves stages of the reaction initiation, the copolymer formation, and the formation of a polyaniline layer at the copolymer/solution interface. 相似文献
52.
We analyse a model for equilibrium configurations of composite systems of nematic liquid crystal with polymer inclusions, in the presence of an external magnetic field. We assume that the system has a periodic structure, and consider the relaxed problem on the unit length constraint of the nematic director field. The relaxation of the Oseen–Frank energy functional is carried out by including bulk as well as surface energy penalty terms, rendering the problem fully non‐linear. We employ two‐scale convergence methods to obtain effective configurations of the system, as the size of the polymeric inclusions tends to zero. We discuss the minimizers of the effective energies for, both, the constrained as well as the unconstrained models. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
53.
54.
两段级联掺铒光纤放大器的优化研究 总被引:7,自引:4,他引:3
基于Giles模型,研究了980 nm和1480 nm泵浦的两段级联掺铒光纤放大器(EDFA)的设计,得出了掺铒光纤(EDF)的最佳长度和光隔离器的最佳位置随泵浦功率和信号功率的变化关系.比较980 nm和1480 nm泵浦的两段级联EDFA,可以发现,前者的最佳EDF长度短,而光隔离器最佳位置距EDFA输入端远. 相似文献
55.
首先叙述了光纤传输Nd~(3+): YAG激光的优点,接着分析了不同光纤和其传输Nd~(3+): YAG激光的特点。然后通过对光纤传输系统各部分的分析与设计,结合实际,设计了光纤耦合机构。最后,对来自于工件反射光问题提出了解决方案。 相似文献
56.
Based on the discrete-structural theory of thin plates and shells, a calculation model for thin-walled elements consisting
of a number of rigid anisotropic layers is put forward. It is assumed that the transverse shear and compression stresses are
equal on the interfaces. Elastic slippage is allowed over the interfaces between adjacent layers. The solution to the problem
is obtained in a geometrically nonlinear statement with account of the influence of transverse shear and compression strains.
The stress-strain state of circular two-layer transversely isotropic plates, both without defects and with a local area of
adhesion failure at their center, is investigated numerically and experimentally. It is found that the kinematic and static
contact conditions on the interfaces of layered thin-walled structural members greatly affect the magnitude of stresses and
strains. With the use of three variants of calculation models, in the cases of perfect and weakened contact conditions between
layers, the calculation results for circular plates are compared. It is revealed that the variant suggested in this paper
adequately reflects the behavior of layered thin-walled structural elements under large deformations.
__________
Translated from Mekhanika Kompozitnykh Materialov, Vol. 41, No. 6, pp. 761–772, November–December, 2005. 相似文献
57.
An all-optical fiber nonlinear Fabry-Perot resonator is proposed. The steady-state model for describing this resonator is developed. The transmission and refection bistabilities are shown numerically. Our results show that the bistability in this system is similar to that in a normal nonlinear Fabry-Perot etalon, except that the characteristics of the bistability can be changed not only by the cavity length but also by the phase shifts of the fiber loop mirrors. 相似文献
58.
提出了折射率温敏式光纤温度传感器的理论模型,包括子午光线和偏射光线的影响,讨论了多模光纤的弯曲损耗,理论的分析和结果与实验相当一致。 相似文献
59.
用紫外光直接在光纤内写入布拉格反射光栅的实验研究 总被引:2,自引:0,他引:2
用紫外光直接在光纤内写入布拉格反射光栅的实验研究杜卫冲谭华耀*刘颂豪华南师范大学,激光生命科学研究所,广州510631*香港理工大学,电机系自1989年Meltaz[1]首次提出采用两束波长位于掺Ge-石英光纤吸收带内的相干紫外激光相干涉,从侧面照射... 相似文献
60.
V.I. Fernández A. Iucci C.M. Naón 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,30(1):53-56
We present an extension of the Tomonaga-Luttinger model in which left and right-moving particles have different Fermi velocities.
We derive expressions for one-particle Green's functions, momentum-distributions, density of states, charge compressibility
and conductivity as functions of both the velocity difference ε and the strength of the interaction β. This allows us to identify
a novel restricted region in the parameter space in which the system keeps the main features of a Luttinger liquid but with
an unusual behavior of the density of states and the static charge compressibility κ. In particular κ diverges on the boundary
of the restricted region, indicating the occurrence of a phase transition.
Received 20 May 2002 / Received in final form 23 August 2002 Published online 19 November 2002 相似文献