一类具有阶段结构和时滞的捕食系统的持续生存和稳定性

我们提出和研究一类带有阶段结构和时滞的捕食模型,得到了种群持续生存的充分条件.研究了阶段结构和时滞对系统稳定性的影响,获得了系统发生Hopf分支和稳定性的条件以及轨道渐进稳定的周期解的存在性.     

Bistable Behaviour of N Two-Level Atoms Interacting with the Field inside a High-Q Cavity Containing a Nonlinear Kerr-Like Medium

Taking the intensity-dependent coupling between atoms and cavity mode into account, we investigate a system consisting of N homogeneously broadened two-level atoms interacting with the field inside a single-mode Fabry- Perot cavity containing a nonlinear Kerr-like medium. We derive the steady-state bistable behaviour of the system, and further analyse in details the influence of several critical parameters on the bistable behaviour.     

KNSBN晶体猫式互抽动相位共轭光特性

在KNSBN：Ce晶体中，利用二波耦合作用，在单一光束无法获得相位共轭光的条件下，实现了“猫”式互抽运相位共轭光输出，获得较高的共轭光发射率，实验结果表明，晶体的二波耦合作用可以使晶体的自抽运相位共轭光的阈值光强降低。入射光的入射角范围增大，响应时间缩短。     

大型爆轰实验示波器组群控制系统

针对爆轰实验中示波器的应用特点，介绍大型爆轰实验示波器组群控制系统。分析了基于GPIB接口的示波器组群的硬件连接方式，控制软件的组成，示波器的实验过程控制方式，数据存储格式和示波器组群控制系统的安全措施。     

D—Wave Kondo Problem in a Square Tight—Bounding Lattice

A Kondo model in a square tight-bonding lattice of conduction electrons is considered.The Kondo interaction takes a d-wave.Using mean-field theory and numerical simulations,it is found that there is a pseudo-gap for the impurity density of states at the Fermi level.Numerical results also show that the exponents of the lowtemperature thermodynamic quantities are non-universal but dependent on the interaction.     

透镜初级球差的横向剪切干涉条纹研究

利用玻璃平行平板构成简单的横向剪切干涉仪可以观察到单薄透镜形成的准直光束的剪切干涉条纹,由干涉条纹分布求出对应的几何像差和离焦量.用焦距为190 mm的单薄透镜做实验,实验结果与计算机模拟结果符合,说明可以从剪切干涉条纹的分布求出透镜的轴向调整误差和初级球差.     

Phase—Locking in Coupled Chaotic Oscillators

The transition from the phase-unlocking state to the phase-locking state is found at the desynchronization of synchronous chaos of coupled oscillators.In the phase-locking case,the motions of all oscillators are chaotic and desynchronized,however spatial ordering is identified in their phase distribution.     

Paul阱中共面两离子系统的能量本征态

通过对Paul阱中共面两离子体系的研究，考虑共面两离子在Paul阱中库仑关联，得到了两离子系统Schrdinger方程的精确解；椐方程的精确解，分析了质心能级简并情况，计算了两离子的平衡距离和低能级的几个态函数，设计程序作出了质心径向概率分布图. 关键词： Paul阱 两离子 共面 量子逻辑操作     

Nonlocality Property of Three—Mode Correlated Fields

Four three-mode correlated states are generated by two beam splitters.We show that,by means of parity measurement,those light fields exhibit the nonlocality represented by the violation of the Bell inequality.The conditions fo the maximum violation are also studied.     

A New Method for the Raman Spectra Calculation of Vitreous or Molten Silicate

A new method is deduced to calculated the Raman spectra of vitreous or molten silicate.This method includes five steps:(i) molecular dynamics simulation to generate thousands of vitreous or molten configurations in equilibrium;(ii)decomposing the configurations into five kinds of defined tetrahedral units;(iii) normal vibrational analysis with Wilson‘s GF matrix method for the eigenfrequencies and eigenvectors of each tetrahedral unit;(iV) Raman intensity calculations for each vibrational mode by utilizing the electro-optical parameter method and bond polarizability model;(v)accumulating the data of frequencies and corresponding intensities to form the prtial Raman spectral line of each defined tetrahedral unit and finally the envelope.