强场一维模型问题的保Wronskian守恒算法

提出辛算法是保Wronskian守恒的算法,把辛算法应用于强激光场一维模型的计算中,结果显示,Wronskian保持不变,与理论分析一致。     

二维非均匀介质中大地电磁响应的计算

在二维埋均匀介质中,将大地电磁问题可看作电磁波在有耗开放波导中的传播问题,借用研究波导问题的数值模式匹配法予以解决,在计算Ex型问题时,使用Hermite基函数和非均匀无素;在计算Hx型问题时,使用变型Hermite基函数,并与有限元法进行了比较。     

Dawson结构杂多化合物(C5H6N)4.5H1.5(P2W18O62)·1.5H2O的水热合成及晶体结构

用水热合成方法制备了Dawson结构杂多化合物(C5H6N)4.5H1.5(P2W18O62).1.5H2O,通过红外光谱和X射线单晶衍射对其进行了表征.结果表明,该化合物属于单斜晶系,C2/m空间群.a=2.6970(3)nm,b=1.39730(16)nm,c=2.0777(2)nm,β=102.33(0)°,V=7.64927(364)nm3,Z=4,R=0.0412,wR2=0.1016.标题化合物阴离子通过质子化的吡啶分子在氢键作用下形成了一维无限链状结构.     

Response of saturated porous media subjected to local thermal loading on the surface of semi-infinite space

Heat source function method is adopted in the present paper to derive elementary solutions of coupled thermo-hydro-mechanical consolidation for saturated porous media under conjunct actions of instantaneous point heat source, instantaneous point fluid source and constant volume force. By using the so-called fictitious heat source method and images method, the solutions of a semi-infinite saturated porous medium subjected to a local heat source with time-varied intensity on its free surface are developed from elementary solutions. The numerical integral methods for calculating the unsteady temperature, pore pressure and displacement fields are given. The thermomechanical response are analyzed for the case of a circular planar heat source. Besides, the thermal consolidation characteristics of a saturated porous medium subjected to a harmonic thermal loading are also given, and the fluctuation processes of the field variables located below the center of heat source are analyzed. The project supported by the National Natural Science Foundation of China (50578008) The English text was polished byYunming Chen.     

Correspondence Between Oscillations and Emitted Photon Closed-Orbits in Spontaneous Emission Rate of an Atom Near a Dielectric Slab

We study the oscillations in the spontaneous emission rate of an atom near a dielectric slab. The emission rate is calculated as a function of system size using quantum electrodynamics. It exhibits multi-periodic oscillations. Four frequencies of the oscillations are extracted by Fourier transforms. They agree with actions of photon closed-orbits going away and returning to the atom. These oscillations are explained as manifestations of quantum interference effects between the emitted photon wave near the atom and the returning photon waves travelling along various closed-orbits.     

Three-Mode Cyclic Squeezed States Constructed via EPR Entangled State

We construct the three-mode cyclic squeezed states and analyze its squeezing property by using the technique of integration within an ordered product of operators and the natural representation of the two-mode squeezing operator in the Einstein-Podolsky-Rosen entangled state basis.     

Cavity Field Spectra of a Cascade Three-Level Atom Interacting with a Single-Mode Field with Kerr-Like Medium

The cavity field spectrum of a cascade three-level atom interacting with single-mode field with Kerr-like medium in the cavity is investigated. The numerical results for the initial field in pure number state, coherent state and squeezed vacuum state are calculated, respectively. It is found that the Kerr-like medium affects the spectral structure even though the initial field is in vacuum when the atom is in upper level. In the case of strong input field, the number state spectrum shows two peaks with different heights; and the superposition state spectrum shows a multipeak structure with an equal distance of two neighboring peaks. The spectral ＂central frequency＂ shifts away from the resonant frequency with the increasing of average photon number.     

双环斑激光束在克尔介质中的自聚焦和光斑分裂效应

实验上发现了双环斑激光束在克尔介质中的光斑分裂效应。理论上,通过数值求解非线性薛定谔方程,发现当输入光斑功率超过100 kW/cm2时,产生光斑分裂和自聚焦效应,该阈值明显小于单环斑激光的自聚焦和光斑分裂阈值。我们认为是双环之间的耦合效应导致了这种结果,并给出了具体分析。     

三电极共面介质阻挡放电的放电特性及诱导气流实验研究

等离子体流动控制激励器由于其响应速度快、激励频带宽、能量损耗低、可靠性强的优势,在航空航天领域的主动流动控制等方面得到了广泛应用.文章提出了一种新型的等离子体气动激励器——三电极共面介质阻挡放电激励器,研究了该激励器电极结构对放电特性和诱导气流速度的影响,并与传统共面介质阻挡放电和沿面介质阻挡放电激励器进行了比较.结果表明:（1）随着激励电压的提高,高压电极和地电极之间先出现了丝状放电并逐渐延伸到第三电极;（2）随着第三电极与高压电极之间的距离增大,诱导气流速率从2.4 m/s下降到0 m/s,而第三电极宽度的变动对诱导气流速度影响可忽略不计;（3）相同外部条件下,该激励器诱导的气流速度小于沿面介质阻挡放电激励器,但高于共面介质阻挡放电激励器.      

一维细胞神经网络的完全稳定性分析

运用Lyapunov函数方法,讨论了一维细胞神经网络模型的完全稳定性问题,给出了四组使模型具有完全稳定的充分条件.