基于单Fabry-Perot标准具的双频率多普勒激光雷达数据反演技术

本文导出了大气后向散射信号光入射到Fabry-Perot (F-P)标准具的有效透过率表达式. 在基于单F-P 标准具的双频率多普勒激光雷达系统中, 采用平均值法定量分析了瑞利后向散射信号对风场测量准确度的影响. 提出了同时反演风速和后向散射比的非线性迭代方法, 并通过仿真试验验证了该方法的有效性. 同时, 导出了径向风速和后向散射比测量误差的具体表达式, 并据此进行了仿真. 仿真结果表明: 若假定望远镜接收到的总后向散射光子数为50000, 径向风速测量误差随后向散射比的增大迅速减小, 在±25 m/s的风速测量动态范围内, 当R_β > 1.2时, 误差小于3 m/s; 后向散射比测量误差随后向散射比的增大而增大, 与径向风速大小几乎无关, 当R_β<10时, 相对误差小于13%. 关键词： 多普勒激光雷达 Fabry-Perot标准具 边缘技术 双频率     

多重敏感性双亲共聚物P(DM-co-AA-co-CA)的自组装及性能

以甲基丙烯酸二甲胺乙酯（DM）、丙烯酸（AA）和香豆素丙烯酸酯化物（CA）为共聚单体,通过普通自由基溶液聚合合成了多重敏感性双亲共聚物P(DM-co-AA-co-CA),用傅里叶变换红外（FTIR）、核磁共振（1H-NMR）、凝胶渗透色谱（GPC）和差示扫描量热仪（DSC）对聚合物结构进行表征．在选择性溶剂四氢呋喃/水中对所得多重敏感性双亲共聚物P(DM-co-AA-co-CA)进行自组装,结果表明,调节组装环境的pH值可以得到荷正电或负电的两性胶束粒子．用紫外可见光分光光度计、荧光分光光度计、Zeta电位测定仪、DLS和TEM研究了多重敏感性双亲共聚物的溶液自组装及其组装体的性能,结果显示,调节pH值可以有效的控制胶束的粒径大小及其LCST,并在pH为8.54时胶束溶液的紫外吸收和荧光发射强度达到最大值,且该胶束溶液在酸碱性较强时具有良好的乳化性能．     

Study of second-order nonlinear hyperpolarisability of all-trans-β-carotene in solutions by linear spectroscopic technique

This paper demonstrates the second-order nonlinear hyperpolarisability \gamma of all-trans-β-carotene in different solvents by linear spectroscopic technique that is based on resonance Raman scattering and UV--VIS (Ultraviolet-visible) absorption spectroscopy. Owing to the two-level model well describing the link that exists between the resonance Raman scattering and stimulated Raman scattering, the stimulated Raman polarisability α_{\rm R} can be calculated through the two-photon resonance system. The value of \gamma of all-trans-β-carotene in carbon bisulfide solution is 6.435\times 10^{-33} esu (1~esu of resistance =8.98755\times10^{11}~\Omega) that is close to the true value, because the solution of all-trans-β-carotene in carbon bisulfide satisfies the rigid resonance Raman scattering condition. This method is expected to be worthy of applications to measure the second-order nonlinear hyperpolarisability of a conjugate organic molecule.     

Breathers and Rogue Waves Derived from an Extended Multi-dimensional N-Coupled Higher-Order Nonlinear Schrödinger Equation in Optical Communication Systems

In this paper, an extended multi-dimensional N-coupled higher-order nonlinear Schrödinger equation (NCHNLSE), which can describe the propagation of the ultrashort pulses in wavelength division multiplexing (WDM) systems, is investigated. By the bilinear method, we construct the breather solutions for the extended (1+1), (2+1) and (3+1)-dimensional N-CHNLSE. The rogue waves are derived as a limiting form of breathers with the aid of symbolic computation. The effect of group velocity dispersion (GVD), third-order dispersion (TOD) and nonlinearity on breathers and rogue waves solutions are discussed in the optical communication systems.     

分析端接频变负载的多导体传输线FDTD新方法

提出了一种新的有效求解端接频变负载的时域有限差分法（FDTD）.该方法将频域导纳经矢量匹配后以有理式表示,通过逆傅里叶变换将其转换到时域,基于分段线性递归卷积法,推导出该导纳两端的电压和电流关系,将其代入到传输线FDTD模型中,得到了求解端接频变负载多导体（MTL）传输线FDTD的一般公式.对一典型电路进行了仿真,和以状态变量法求解任意负载的结果进行了对比,两者基本重合,说明该方法用来求解频变负载是有效的. 关键词： 多导体传输线 分段线性递归卷积 时域有限差分法 任意负载     

Symmetry Groups and New Exact Solutions to (2+1)-Dimensional Variable Coefficient Canonical Generalized KP Equation

In this paper, the modified CK's direct method to find symmetry groups of nonlinear partial differential equation is extended to (2 1)-dimensional variable coefficient canonical generalized KP (VCCGKP) equation. As a result, symmetry groups, Lie point symmetry group and Lie symmetry for the VCCGKP equation are obtained. In fact, the Lie point symmetry group coincides with that obtained by the standard Lie group approach. Applying the given Lie symmetry, we obtain five types of similarity reductions and a lot of new exact solutions, including hyperbolic function solutions, triangular periodic solutions, Jacobi elliptic function solutions and rational solutions, for the VCCGKP equation.     

可以作为宇宙结构特征的作用量■(n)——天文系统的角动量、质量和两者的关系

通过一般的理论考虑,本文得到了可以作为特征物质在宇宙中各种典型尺度n上的行为作用量子,其中h,G,e和m_a分別是Planck作用量子、引力常数、基本电荷和基本粒子的有效质量,n是尺度参数。由此进一步得到了可与观测比较的、各种天文系统的特征角动量谱J(n)=hⁿ、质量谱Mⁿ=(hⁿCα/G)^1/2和两者的关系Jⁿ/(Mⁿ)²≈G/Cα,其中C是光速、α是精细结构常数。     

聚多巴胺功能化的四氧化三钴纳米复合材料的制备及电催化性能

通过简单的自聚合反应在四氧化三钴表面包覆聚多巴胺膜,联合使用纳米铂和辣根过氧化物酶用于电催化还原过氧化氢。结果表明,聚多巴胺的使用增强后续纳米铂的负载量和辣根过氧化物酶的生物活性;四氧化三钴、纳米铂和辣根过氧化物酶的多重信号放大作用,大大增强了该复合材料的催化活性,提高了过氧化氢传感器的灵敏度。优化实验条件下,传感器对过氧化氢的检测范围为0.1～700μmol·L^-1,检测限为0.08μmol·L^-1。     

New Families of Nontravelling Wave Solutions to Two (3+1)-Dimensional Equations

In this paper, two (3+1)-dimensional equations are investigated. Auto-Bäcklund transformation is obtained, which is used with some ansatze to seek new types of exact solutions including some arbitrary functions. When these arbitrary functions are taken as some special functions, these solutions possess abundant structures. These solutions contain soliton-like solutions and rational solutions.     

New Method for Finding a Series of Exact Solutions to Generalized Breaking Soliton Equation

In this paper, a new generalized extended tanh-function method is presented for constructing soliton-like,period-form solutions of nonlinear evolution equations (NEEs). This method is more powerful than the extended tanhfunction method [Phys. Lett. A 277 (2000) 212] and the modified extended tanh-function method [Phys. Lett. A 285 (2001) 355]. Abundant new families of the exact solutions of Bogoyavlenskii‘s generalized breaking soliton equation are obtained by using this method and symbolic computation system Maple.