利用特征为2域上伪辛几何中1维非迷向子空间构作PBIB设计

关于结合方案和PBIB设计的定义及所用的有关符号见文献[1].设F_q为特征为2的有限域,q=2~r.熟知F_q上的对称矩阵合同于以下三种形式的矩阵(见[1]p.24).     

Synthesis of grafted poly(p‐phenyleneethynylene) with energy donor–acceptor architecture via atom transfer radical polymerization: Towards nonaggregating and hole‐facilitating light‐emitting material

In this contribution, we demonstrate a new effective methodology for constructing highly efficient and durable poly(p‐phenyleneethynylene) (PPE) containing emissive material with nonaggregating and hole‐facilitating properties through the introduction of hole‐transporting blocks into the PPE system as the grafting coils as well as building the energy donor–acceptor architecture between the grafting coils and the PPE backbone. Poly(2‐(carbazol‐9‐yl)ethyl methacrylate) (PCzEMA), herein, is chosen as the hole‐transporting blocks, and incorporated into the PPE system as the grafting coils via atom transfer radical polymerization. The chemical structure of the resultant copolymer, PPE‐g‐PCzEMA, was characterized by NMR and gel permeation chromatography, showing that the desirable copolymer was obtained with the narrow polydispersity. The increased thermal stability of PPE‐g‐PCzEMA was confirmed by thermogravimetric analysis and differential scanning calorimetry along with its macroinitiator. The optoelectronic properties of this copolymer were studied in detail by ultraviolet‐visible absorption, photoluminescence emission and excitation spectra, and cyclic voltammogram (CV). The results indicate that PPE‐g‐PCzEMA exhibits the solid‐state luminescent property dominated by individual lumophores, and also the energy transfer process from the PCzEMA blocks to the PPE backbone with a relatively higher energy transfer efficiency in the solid‐state compared to that of the solution state. Additionally, the hole‐injection property is greatly facilitated due to the presence of PCzEMA, as confirmed by CV profiles. All these data indicate that PPE‐g‐PCzEMA is a good candidate for use in optoelectronic devices. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3776–3787, 2007     

资源共享方式若干问题的研讨

社会公用服务系统和工程技术系统，存在共同的资源共享问题。本文通过典例就资源共享方式的若干问题加以探究：讨论广义的多用户系统中人工资源共享方式的分类；阐述常用的共享方式的特点、优缺点；分析系统时间性能及其改进与共享方式的关系等。文章还提出在系统工程范畴里，应对社会公用服务和工程技术两类系统的资源共享方式予以综合研究，并相互借鉴和移植。     

浅议物理实验教学环节改革

为进一步提高大学物理实验的教学质量，本文就实验课的预习、操作、实验报告的撰写及考核方法进行了探讨。     

The multi-symplecticity of partitioned Runge-Kutta methods for Hamiltonian PDEs

In this article we consider partitioned Runge-Kutta (PRK) methods for Hamiltonian partial differential equations (PDEs) and present some sufficient conditions for multi-symplecticity of PRK methods of Hamiltonian PDEs.

     

Reduction of Dislocations in GaN Epilayer Grown on Si （111） Substrates using a GaN Intermedial Layer

GaN intermedial layers grown under different pressures are inserted between GaN epilayers and AIN/Si（111） substrates. In situ optical reflectivity measurements show that a transition from the three-dimensional （3D） mode to the 2I） one occurs during the GaN epilayer growth when a higher growth pressure is used during the preceding GaN intermedial layer growth, and an improvement of the crystalline quality of GaN epilayer will be made. Combining the in situ reflectivity and transmission electron microscopy （TEM） measurements, it is suggested that the lateral growth at the transition of growth mode is favourable for bending of dislocation lines, thus reducing the density of threading dislocations in the epilayer.     

一种非刚性医学图像点匹配方法

提出了一种非刚性点匹配的算法并把其运用于医学图像配准．该算法采用信号滤波的方法来获得点集间的匹配信息，并运用松弛标记法将各点邻域关系对模糊的匹配信息进行迭代获得明确的匹配关系．在此基础上，利用高斯径向基函数来描述点模式间的弹性形变，在基本的迭代框架下实现问题的求解．实验结果显示在形变程度为5％、出格点比率50％和噪声标准差为5％的情况下该算法的匹配误差能控制在0．13以下，表明了该算法的鲁棒性和有效性，较好地解决了医学非刚性形变的点匹配问题．     

Beam Combination using Stimulated Brillouin Scattering for the Ultimate High Power-Energy Laser System Operating at High Repetition Rate over 10 Hz for Laser Fusion Driver

After the laser was invented in 1960, a phase conjugation mirror has been respected to be the most fantastic one for the laser resonator composition because it can compensate any distortions of the laser beams occurred by the many inhomogenuities of the laser media and optical components. Among the many phase conjugation configurations, the stimulated Brillouin scattering phase conjugation mirror is the most simple one and many researchers have tried to utilize it to develop high power/energy laser systems. For realizing a high energy/power laser system the thermal problem is the most difficult to solve, and some researchers suggested a beam combination technique to reduce the thermal load of the big laser media to many small sized ones. To accomplish the beam combination using stimulated Brillouin scattering phase conjugation mirrors (SBS-PCMs), it is necessary to lock/control the phases of the SBS-PCMs. And some researchers have developed several ways for it, but they can lock the phases of a limited number of beams overlapped at the foci less than 5, or lock the phases by back-seeding technique but it loses the phase conjugation characteristics. For realization of the laser fusion driver, it is necessary to combine more than 10 or 100 beams. And the authors have developed recently a new phase controlling/locking technique which is isolated and independent totally from other beams and it can be applied to an unlimited number of beams in principle.     

A highly sensitive and rapid assay for protein determination in human urine and penicillin using a Rayleigh light-scattering technique with benzeneazo-8-acetylamino-1-naphthol-3,6-disulfonic acid sodium salt.

A simple and sensitive method was conducted for the determination of trace amounts of proteins with benzeneazo-8-acetylamino-1-naphthol-3,6-disulfonic acid sodium salt (azophloxine, AP) using a Rayleigh light-scattering (RLS) technique. At pH 2.60 and in the presence of an emulsifier OP microemulsion, the RLS of AP can be greatly enhanced by proteins, owing to the interaction between AP and protein. The enhanced intensity is proportional to the concentration of proteins. Four proteins, including bovine serum albumin (BSA), human serum albumin (HSA), lysozyme (Lys) and gamma globulin (gamma-G) have been tested. For example, the linear range of BSA was 0 - 0.06 microg mL(-1) with detection limits of 2.38 ng mL(-1). The method was applied to the analysis of protein in human urine and penicillin samples with satisfactory results. The relative standard deviation was in all instances less than 4.0%, and the recovery was in the range of 97.5 - 104%.     

Effect of a low magnetic field on crystallinity and magnetic susceptibility of molecular magnet {NBu4[FeCr(ox)3]}x (NBu4=tetra( n-butyl) ammonium ion; ox=oxalate ion)

Molecular magnet {NBu₄[Fe Cr(ox)₃]}_x (NBu₄⁺=tetra(n-buty1) ammonium ion; ox²⁻=oxalate ion) was synthesized under an applied low magnetic field of 0.3 T in comparison to that synthesized without a field. Their crystallinities, morphologies and magnetic properties were characterized by using the X-ray diffractionmeter, the transmission electron microscope, and a superconducting quantum interference device. It is found that the average size of particles synthesized under the applied field appears larger than that synthesized without a field. Moreover, its crystallinity, morphology and magnetic susceptibility have also been improved. However, its chemical structure and ferromagnetic phase transition temperature T_c do not change. Possible reasons to explain this effect are also discussed.