In-phase output beam from broad-area diode array using Talbot cavity

The robust phase locking of a linear diode array consisting of 49 broad-area emitters was demonstrated.The single lobe in the far field with output power of 0.83 W was observed. The far-field divergence was reduced to 2.0 mrad. The spectral bandwidth was reduced from 1.7 to 0.13 nm.     

Experimental investigation on bit-rate-adaptive software synchronous optical sampling

A tunable optical rail is embedded into the cavity of a nonlinear-polarization-rotation(NPR) mode-locked fiber laser to generate a sampling pulse with different repetition frequencies and realize bit-rate-adaptive software synchronous optical sampling.Two ultrashort pulses(20.26677 and 20.22900 MHz) are derived,and a 100-MHz data signal is sampled twice with these pulses based on sum-frequency generation(SFG) in periodically poled lithium niobate(PPLN).The eye diagram is successfully recovered,and an estimated bit rate of 102.22 MHz is derived.This method is feasible for bit rates ranging from 200 MHz to 1 GHz,with <3% relative error.     

Tricyanometalate molecular chemistry: A type of versatile building blocks for the construction of cyano-bridged molecular architectures

Cyano-bridged molecule-based magnetic materials with reduced dimensionality, such as single-molecule magnets (SMMs) and single-chain magnets (SCMs), have attracted great research interest during the last decade. Among the cyano-based molecular precursors with ample coordinating capability, we note the ability of the tricyanometalate to link various metal ions lead to a wide diversity of structural architectures ranging from discrete polynuclear complexes to various one-dimensional (1D) assemblies. Some of them are promising cyano-bridged SMMs and SCMs. The use of capping tridentate organic ligands results in a number of clusters containing di-, tri-, tetra-, penta-, hexa-, octa-, fourteen-nuclear and various 1D metal-cyanide molecular architectures. Here we review the structural topologies of these complexes and their related magnetic properties, highlight typical examples, and point out the main possible directions that remain to be developed in this field. From the crystal engineering point of view, the compounds reviewed here should provide useful information for further design and investigation on this elusive class of cyano-bridged SMMs and SCMs.     

Morphology and optical absorption of Bi2Fe4O9 crystals via mineralizer-assisted hydrothermal synthesis

Submicron-sized Bi₂Fe₄O₉ crystals were successfully synthesized via the hydrothermal method, while micron-sized Bi₂Fe₄O₉ crystals with rod-like morphologies were obtained in the presence of the mineralizer KNO₃. X-ray diffraction, scanning electron microscopy and transmission electron microscopy were employed to characterize the products. According to a series of time-dependent experiments, it was concluded that the likeliest formation mechanism for the microrods was the Ostwald ripening process. It was proposed that the blocking effect of NO₃^? contributed to the formation of the rod-like powders. Moreover, the optical absorption of the prepared Bi₂Fe₄O₉ crystals was measured using an UV–vis spectrophotometer, indicating that Bi₂Fe₄O₉ powders can be used as effective photocatalysts under visible light.     

Fast sensitivity analysis of defective system

Sensitivity analysis of linear vibration system is of wide interest. In this paper, sensitivity analysis based on non-defective system and defective system is summarized in all cases. Specially, for the defective systems, a fast method for the perturbation problem of state vectors is constructed in terms of the theories of generalized eigenvectors and adjoint matrices. By this method, the state vector derivatives can be expressed by a linear combination of generalized eigenvectors. The expansion coefficients can be obtained without solving large-scale equations based on eigensolutions of original system. Numerical results demonstrate the effectiveness and the stability of the method.     

超导滤波器专用设计软件

开发了一套适用于高温超导滤波器设计的专用软件。利用该软件可快速得出高达20阶的任意结构的任意类型滤波器的传输方程、原型电路,并提取出其耦合系数矩阵。该软件可分析寄生耦合、基片厚度,介电常数误差等对滤波器的性能影响,并能由蒙特卡罗(Monte Carlo)法预测超导滤波器的产品合格率。此外,该软件提供了一个基于神经网络模型的计算机辅助调谐工具包。因而可解决超导滤波器设计、调谐的几乎所有问题,大大降低了其研制的难度和产业化的门槛。     

电离层电场电流半球模式——Ⅰ.理论分析

从定常态电离层电荷守恒方程和欧姆定律出发,导出了适用于整个半球、同时包含中性风和场向电流这种效应的电离层电场、电流基本方程组.在电离层积分电导率和中性风已知的条件下。建立了两类定解问题,并给出了数值求解方案.     

Study of the Electrical Double Layer of a Spherical Micelle: Functional Theoretical Approach

The electrical double layer theory is the base of the colloid stability theory (DLVO theory), and the PB eq. is a key to the study of the layer1,2. For a spherical particle, the PB eq. is (1) where and are the dielectric constant of the medium, the valence of ions, the elementary charge, the concentration of ions far away from the particle, the Boltzmann's constant and the temperature of the system, respectively. Since this eq. is a second order nonlinear differential one, only the anal…