施主中心量子点能谱分析

在有效质量近似下，使用数值矩阵对角化的方法，得到了高斯束缚势下施主中心量子点的能谱，并与简谐势相比较.结果显示施主中心量子点基态及低激发态的性质主要取决于量子点的尺寸、束缚势的强度及形状. 关键词： 施主中心量子点 高斯势阱 能谱     

Additivity of statistical moments in the exponentially modified Gaussian model of chromatography

A homologous series of saturated fatty acids ranging from C₁₀ to C₂₂ was separated by reversed-phase capillary liquid chromatography. The resultant zone profiles were found to be fit best by an exponentially modified Gaussian (EMG) function. To compare the EMG function and statistical moments for the analysis of the experimental zone profiles, a series of simulated profiles was generated by using fixed values for retention time and different values for the symmetrical (σ) and asymmetrical (τ) contributions to the variance. The simulated profiles were modified with respect to the integration limits, the number of points, and the signal-to-noise ratio. After modification, each profile was analyzed by using statistical moments and an iteratively fit EMG equation. These data indicate that the statistical moment method is much more susceptible to error when the degree of asymmetry is large, when the integration limits are inappropriately chosen, when the number of points is small, and when the signal-to-noise ratio is small. The experimental zone profiles were then analyzed by using the statistical moment and EMG methods. Although care was taken to minimize the sources of error discussed above, significant differences were found between the two methods. The differences in the second moment suggest that the symmetrical and asymmetrical contributions to broadening in the experimental zone profiles are not independent. As a consequence, the second moment is not equal to the sum of σ² and τ², as is commonly assumed. This observation has important implications for the elucidation of thermodynamic and kinetic information from chromatographic zone profiles.     

Uniform convergence of the free energy of the classical Heisenberg model to that of the gaussian model

We show that the free energy of the classical Heisenberg model converges to the free energy of the Gaussian in the low-temperature limit. The limit is uniform as the field is taken to zero.     

BEPCII横向束流反馈系统前端电子学

选择了一台商业化的前端电子学RFTF（radio frequency front-end for transverse feedback system）用于BEPCII横向束流反馈系统, 这是跟进世界先进加速器技术的具体实施。在BEPC同步运行模式下对RFTF的性能进行了测试实验，结果表明使用RFTF可以得到理想的波形，能够满足BEPCII横向反馈系统的需要，但是，当储存环出现不稳性时，系统无法正常工作，这就要求BEPCII纵向不稳定很小或者用纵向反馈系统来抑制存在的纵向不稳定。     

Convergence acceleration of some Gaussian quadrature formulas for analytic functions

Let (S_n) be the sequence given by the Jacobi-Gauss quadrature method when the integrand is an analytic function with a lopatilluric singularity or with a branch point on the real axis, and S its limi. We give an asymptotic representation of the errors S − S_n and of S_n+s − S_n, which leads to building other sequences which give a better approximation of the exact value of the integral than S_n. All the results are illustrated by numerical examples.     

两步离子交换玻璃光功分器的折射率分布

介绍了在用两步离子交换方法制作光功分器中，在高斯分布为初始条件下采用平均法求出非线性两步离子扩散方程的折射率分布，与实验测出的折射率分布符合得很好。该法尤其对单模光功分器求其折射率更为简单和实用。     

Coherence resonance and synchronization of Hindmarsh-Rose neurons with noise

Noise effects on coherence resonance and synchronization of Hindmarsh-Rose (HR) neuron model are studied. The coherence resonance of a single HR neuron with Gaussian white noise added to the membrane potential is investigated in situations before, near and after the Hopf bifurcation, separately, with the external direct current as a bifurcation parameter. It is shown that even though there is no coupling between neurons, uncoupled identical HR neurons driven by a common noise can achieve complete synchronization when the noise intensity is higher than a critical value. Furthermore, noise also enhances complete synchronization of weakly coupled neurons. It is concluded that synchronization in bursting neurons is easier to be induced than in spiking ones, and coupling enhances the sensitivity of synchronization of neurons to noise stimulus.     

Approximation of the Hilbert Transform on the real semiaxis using Laguerre zeros

The authors propose two new algorithms for the computation of Cauchy principal value integrals on the real semiaxis. The proposed quadrature rules use zeros of Laguerre polynomials. Theoretical error estimates are proved and some numerical examples are showed.     

Tail Properties of Correlation Measures

We study the tail properties of a class of Borel probability measures, called correlation measures. We show that (i) there exist correlation measures with exponentially decaying tail probabilities, and (ii) roughly speaking, no correlation measure may have smaller tail probabilities than a Gaussian measure.     

散斑位移量与照明激光束特性关系的实验研究

激光照射到粗糙物体的表面会形成激光散斑，散斑随物体的运动而运动，特别是物体在自身平面内运动时散斑的同步运动比较显著，因此可以用这一现象测物体的微小位移，散斑运动规律与照明光束的特性有关，本文通过实验研究了不同光束照明下散斑位移的规律，验证了散斑位移理论，并指出散斑位移测量中应注意的问题。