BeH~+(X~1∑~+)离子势能函数及其分子常数研究

本文利用CCSD(T)方法和系列相关一致基,对BeH~+(X~1∑~+)离子的几何结构进行了优化,结果发现在CCSD(T)/aug-cc-pV5Z理论水平下得到的光谱数据(R_e=0.13142 nm,ω_e=2212.7 cm~(-1),D_e=3.1750 eV)与实验值非常接近.在CCSD(T)/aug-cc-pV5Z理论水平下又对BeH~+(X~1∑~+)离子的势能曲线进行了计算,再用最小二乘法将计算结果拟合成了Murrell-Sorbie函数.利用拟合出的解析势能函数,进一步计算出了BeH~+离子X~1∑~+态的其它光谱常数(B_e,α_e,ω_e和ω_ex_e),且与实验及其它理论计算结果进行了比较.以得到的解析势能函数为基础,通过求解双原子分子核运动的径向Schr(o|¨)dinger方程,找到了J=0时基态的全部20个振动态,并求出了每一振动态的振动能级、转动惯量及离心畸变常数(D_v,H_v,L_v,M_v,N_v,O_v).计算结果与实验数据的比较表明,BeH~+(X~1∑~+)离子的势能函数可用Murrell-Sorbie函数来表达,而且由此计算出的光谱常数、振动能级和转动惯量等都达到了相当高的精度.     

Numerical Investigation on Inviscid Instability of Streaky Structures in Incompressible Boundary Layer Flow

Numerical investigation is made on the effect of streaky structures in transition by inviscid linear disturbance equation with temporal mode. Several disturbances with different streamwise wave numbers were induced, and the evolutions with time step were received. It suggests that the exponential growth and periodic variation of the waves are in existence. As the streamwise wave number increases, the disturbance growth rate begins by increasing, reaches a maximum at around α=0.4 with a disturbance frequency of 0.2186 ＋ 0.001457i, and then decreases. Furthermore, the eigenfunctions of pressure disturbance are plotted.     

Decay properties of D and D_s mesons in coulomb plus power potential （CPPν）

The decay properties of the D and D s mesons are computed in a nonrelativistic phenomenological quark-antiquark potential of the type V （r） =-4 /3 α s /r＋ Ar ν with different choices of ν.Numerical method to solve the Schrdinger equation has been used to obtain the spectroscopy of qQ mesons.The numerically obtained radial solutions are employed to obtain the decay constant and leptonic decay widths.It has been observed that predictions of the ground state masses and the decay widths are consistent with other model predictions as well as with the known experimental values.     

激光监听演示实验仪器的制作

本文介绍了激光监听演示实验仪器的制作.设计出功率放大和带通滤波相结合的电路,用此电路接收光电探测器所采集的激光检测声波振动的信号,经还原后进而实现远程监听.论文中涉及实验仪器制作过程中所遇到的问题和相应解决方法,可供学生在演示实验中使用.     

一维抛物势场中单电子量子比特的性质

根据-维抛物势场中单电子能量本征波函数的特点,以基态和第二激发态波函数构造一个量子比特,并研究量子比特的性质.数值计算表明,量子比特内电子的概率密度随空间坐标和时间的变化而变化,在平衡位置概率密度幅值最大,在其他位置相对较小;且各个空间点的概率密度均随时间做周期性振荡,振荡周期完全由抛物势场的性质决定.     

薄膜介质层绕式Blumlein线理论与实验研究

对薄膜介质层绕式Blumlein线的特性参数进行了理论分析。采用Pspice软件对电路模型进行了计算,分析了开关电感、寄生电阻对负载输出波形的影响。结果表明:开关电感的存在使得负载波形前沿变缓,后延波形扭曲变差,寄生电阻会影响负载的电压输出效率。采用模拟软件对传输线中的电磁场分布进行了计算,结果表明薄电极边缘场畸变以及折叠弯曲部分的场变化是绝缘介质耐压必须考虑的因素。基于此理论分析,设计制作了一种新型薄膜介质Blumlein线,绝缘材料为聚酯薄膜,单层薄膜厚100μm,电极为厚50μm的铜皮,单元模块设计耐压50 kV。进行了三级模块串联叠加实验,充电25 kV,匹配负载输出60 kV,脉冲上升沿80 ns,脉冲宽度200 ns。     

吸附氢分子的振动态及熵的计算

用第一性原理方法研究了H_2在(MgO)_9及(AlN)_(12)团簇上的吸附态、振动模式及熵.分析表明,吸附体系的振动中有六个简正模式可归为氢分子的振动;由于氢分子质量很小,零点能修正对吸附能有重要影响.利用振动配分函数计算了吸附氢分子的熵,表明吸附态H_2的熵主要决定于较低的同相振动的频率,并不完全与吸附强度相关;在标准大气压下70—350 K的温度范围内,吸附H_2的熵与气态H_2的熵之间存在很好的线性关系,吸附后H_2的熵减小约10.2R.     

α稳定噪声下一类周期势系统的振动共振

将多个低频微弱信号、高频信号和加性α稳定噪声共同激励的一类周期势系统作为研究模型,以平均信噪比增益(MSNRI)为性能指标,对α稳定噪声环境下周期势系统中的振动共振现象进行了研究,分别探究了α稳定噪声的特征参数α、对称参数β、加性噪声强度放大系数D、高频信号幅值B以及频率?对振动共振输出效应的影响.研究结果表明:1)在不同分布的α稳定噪声环境下,固定频率?(或幅值B),当幅值B(或频率?)逐渐增大时,MSNRI-B(或MSNRI-?)曲线出现多个峰值,即存在多个B区间(或?区间)可诱导振动共振,并且这些区间不会随噪声分布参数α或β的变化而变化;2)当加性噪声强度放大系数D发生变化时,幅值B和频率?的共振区间没有随着D的变化而变化,表明只有高频信号能量向待测低频信号转移,噪声能量并没有向待测低频信号转移.另外当幅值B、频率?固定时,随着D的逐渐增大,依然可以实现微弱信号的检测,表明振动共振可以克服工业现场噪声强度不可调控的缺点.本文研究结果提供了一种新的微弱信号检测方法,在信号处理领域有着潜在的应用价值.     

（2＋2）-Dimensional Discrete Soliton Equations and Integrable Coupling System

In this paper, we extend a （2＋2）-dimensional continuous zero curvature equation to （2＋2）-dimensional discrete zero curvature equation, then a new （2＋2）-dimensional cubic Volterra lattice hierarchy is obtained. Fhrthermore, the integrable coupling systems of the （2＋2）-dimensional cubic Volterra lattice hierarchy and the generalized Toda lattice soliton equations are presented by using a Lie algebraic system sl（4）.     

Analytical Approach to Fractional Zakharov-Kuznetsov Equations by He＇s Homotopy Perturbation Method

The aim of this paper is to obtain the approximate analytical solution of a fractional Zakharov-Kuznetsov equation by using homotopy perturbation method （HPM）. The fractional derivatives are described in the Caputo sense. Several examples are given and the results are compared to exact solutions. The results reveal that the method is very effective and simple.