两原子相干共振能量传递的单次与N次能量提取

两原子间隔一定距离且两原子跃迁频率接近时,两原子之间可发生能量传递.理论研究了供能原子和受能原子两共振原子的能量传递.求解薛定谔方程得出两原子共振能量传递效率.结果表明,供能原子在真空场中的激发态寿命在能量传递效率中起到十分重要的作用.能量传递效率与两原子间距离的负三次幂的正弦值的平方成正比,在一阶近似条件下,与两原子间距离的6次方成反比.以供能原子处于激发态时为初始时刻,能量从初始时刻随时间由供能原子向受能原子传递,对受能原子的单次能量提取的最大值大约在供能原子寿命的2/3时刻;对受能原子的连续N次能量提取的最大值,每次提取时间大约在供能原子寿命的1/2时刻.     

Numerical simulation and inversion validation of the real correlation random wind field generation for coherent Doppler LiDAR

Simulation of the coherent Doppler LiDAR signal requires accurate computation of homogeneous random wind fields. Based on complex random processes with specified spatial statistics given by the covariance function, an improved real correlation random wind field algorithm is proposed for real random processes, the simulation results are compared with the given covariance function and the real correlation algorithm conforms to the given covariance function quite well.     

均匀磁场中二维各向同性带电谐振子的守恒量与对称性研究

由牛顿第二定律得到二维各向同性带电谐振子在均匀磁场中运动的运动微分方程,通过对运动微分方程的直接积分得到系统的两个积分(守恒量).利用Legendre变换建立守恒量与Lagrange函数间的关系,从而求得系统的Lagrange函数,并讨论与守恒量相应的无限小变换的Noether对称性与Lie对称性,最后求得系统的运动学方程.     

On the choice of a regulator for the extraction of depth profiles from ARXPS data obtained on plasma-treated polystyrene

Regularized oxygen concentration depth profiles were extracted from ARXPS data obtained on a plasma-oxidized polystyrene sample, using a variety of regulators and over a wide range of values for the regularization parameter. The plausibility of the profiles obtained was assessed with respect to strong and weak criteria based on a priori considerations. It was found that the most plausible results were obtained with regulators based upon the slopes or the curvatures exhibited in the profile.