叶绿素A较高激发态的发光

采用激发样品表层和样品中心两种激发方式,在300K和77K温度下研究叶绿素A(Chla)的较高激发行为,观测到峰值位于493、520和580nm三条新的荧光发射带.分别测量它们的荧光激发光谱,证明这三条新的荧光带属于Chla的第二激发单线态向基态的不同振动能级的辐射跃迁发光.最后提出电子跃迁模型,同时进行了讨论.     

亚细胞器诱导的2,4,6-三硝基甲苯阴离子自由基的ESR研究

本文在无氧条件下利用ESR分别观察了肝脏和晶状体的微粒体及线粒体酶在NADPH存在下还原三硝基甲苯(TNT)的过程,检测到参数为g=2.0048±0.0005,A_对位~N=1.215mT,A~N=0.800±0.010mT,A~H=0.122±0.0206mT的自由基信号,并通过电子计算机对ESR谱的模拟证明该自由基信号为TNT硝基阴离子自由基,根据其超精细分裂常数认为,其不配对电子的电子云密度主要分布在对位硝基上。     

Vector semi-rational rogon-solitons and asymptotic analysis for any multi-component Hirota equations with mixed backgrounds

The Hirota equation can be used to describe the wave propagation of an ultrashort optical field. In this paper, the multi-component Hirota (alias n-Hirota, i.e. n-component third-order nonlinear Schrödinger) equations with mixed non-zero and zero boundary conditions are explored. We employ the multiple roots of the characteristic polynomial related to the Lax pair and modified Darboux transform to find vector semi-rational rogon-soliton solutions (i.e. nonlinear combinations of rogon and soliton solutions). The semi-rational rogon-soliton features can be modulated by the polynomial degree. For the larger solution parameters, the first m (m < n) components with non-zero backgrounds can be decomposed into rational rogons and grey-like solitons, and the last n − m components with zero backgrounds can approach bright-like solitons. Moreover, we analyze the accelerations and curvatures of the quasi-characteristic curves, as well as the variations of accelerations with the distances to judge the interaction intensities between rogons and grey-like solitons. We also find the semi-rational rogon-soliton solutions with ultra-high amplitudes. In particular, we can also deduce vector semi-rational solitons of the n-component complex mKdV equation. These results will be useful to further study the related nonlinear wave phenomena of multi-component physical models with mixed background, and even design the related physical experiments.     

Noise analysis of an electro-optic sensor system

Optical Review - This paper describes the noise analysis of an electro-optic (EO) sensor system based on experimental and simulation results. We developed a polarization simulator of the EO sensor...     

H+和Ar11+激发Si的K壳层X射线发射研究

测量了50–250 keV H⁺和1.0–3.0 MeV Ar¹¹⁺ 轰击Si表面过程中辐射的X射线. 结果表明, 在Ar¹¹⁺入射的情况下, 引起了Si的L壳层上3, 4个电子的多电离.计算了Si的K壳层X射线产生截面, 并将两体碰撞近似(BEA), 平面波恩近似, ECPSSR理论计算与实验值进行了对比. ECPSSR理论与质子产生的截面数据能够很好地符合; 而考虑多电离后, BEA理论与Ar¹¹⁺的实验结果符合较好. 关键词： X射线 高电荷态重离子 多电离     

一阶Lagrange系统的梯度表示

研究一阶Lagrange系统的梯度表示. 给出一阶Lagrange系统可成为梯度系统的条件. 利用梯度系统的性质研究系统的稳定性. 给出例子说明结果的应用. 关键词： 一阶Lagrange系统 梯度系统 稳定性     

Theoretical calculations of spin-Hamiltonian parameters and defect structures for Cu2+ in trigonally-distorted tetrahedral sites of ZnO and GaN crystals

The spin-Hamiltonian (SH) parameters (g factors g _//, g ⊥ and hyperfine structure constants ⁶³ A _//, ⁶³ A ⊥, ⁶⁵ A _//, ⁶⁵ A ⊥) for Cu²⁺ ions in the trigonally-distorted tetrahedral sites of ZnO and GaN crystals are calculated from a complete diagonalization (of energy matrix) method (CDM) based on a two spin-orbit parameter model for d ⁹ ions in trigonal symmetry. In the method, the Zeeman and hyperfine interaction terms are added to the Hamiltonian in the conventional CDM. The calculated results are in good agreement with the experimental values. The calculated SH parameters are also compared with those using the traditional diagonalization method or perturbation method only within the ² T ₂ term. It appears that, for exact calculations of SH parameters of d ⁹ ions in trigonal tetrahedral clusters in crystals, the present CDM is preferable to the traditional diagonalization method or perturbation method within the ² T ₂ term. The local structures of Cu²⁺ centers (which differ from the corresponding structure in the host crystal) in ZnO : Cu²⁺ and GaN : Cu²⁺ are obtained from the calculations. The results are discussed.     

Preparation and characterization of vinyltriethoxysilane based inorganic–organic gel glasses dispersed 4′-n-pentyl-4-cyanobiphenyl nematic liquid crystal

Vinyltriethoxysilane based inorganic–organic glasses dispersed with 4′-n-pentyl-4-cyanobiphenyl nematic liquid crystal are designed to fabricate a new type of gel glass dispersed with liquid crystal. Scanning electron microscopy shows that the nematic liquid crystal phase, occupying the interconnected cavities, is continuously embedded in the inorganic–organic matrixes. The effect of the nematic liquid crystal weight concentration on the morphology is investigated. The differential scanning calorimetry shows that the nematic-isotropic transition temperature depends on the nematic liquid crystal weight concentration. The Raman spectra show that there are no obvious Raman frequency shifts, compared with pure nematic liquid crystal. The in situ diffuse reflectance FTIR spectra show that the integral intensity of bands of hydroxyls has not varied.     

用楔形柱面光纤微透镜耦合的1.3μm SOA组件

运用激光模式耦合理论分析了半导体光放大器(SOA)与单模通信光纤的连接损耗,并设计制作了楔形柱面光纤微透镜用来实现两者的模斑匹配,有效地降低了器件的光耦合损耗.本文介绍了楔形柱面光纤微透镜耦合的1.3 μm半导体光放大器(SOA)组件及其制作方法.该组件的最大增益不小于14 dB,其偏振灵敏度小于1 dB,增益波动不大于0.5 dB.     

基于模糊PID算法的烘箱控制仿真分析

模糊算法能解决传统方法难以解决模型的不确定性、非线性、复杂等问题的任务,PID算法在定模型下控制稳态性能好,能消除静差等特点．结合这2种方法,提出模糊PID算法,应用于通用烘箱的温度控制,通过仿真分析,表明：对不同烘箱、不同环境下,用该算法控制,有高精度、超调量小,无需调节PID参数,具有智能控制等功能．