前因后果 antecedents and consequences; the beginning and the end of the matter; causes and effects; the sequence of events; later events are the inevitable result of former causes.; the entire process 事情发生了, 就会有它的前因后果。 every thing that happens has a cause and effect
The rate of a process is based upon the energy barrier required to cross the corresponding saddle point , and a harmonic prefactor 越过马鞍点和前因子所需的能量决定该过程的速度。
A0 is bigger when the gasification temperature is higher . as the initial pore structure parameter is affected by the change of pore structure at different pyrolysis temperatures 应用此模型计算四种煤焦反应活化能、指前因子、孔结构参数、 a0等动力学参数值。
It is the main purpose of this paper to calculate the energy splitting of ground state and excited states induced by thermally assisted quantum tunneling . first , a brief introduction is given for the theoretical and experimental studies on the magnetic macroscopic quantum effects . then , spin tunneling in a uniaxial ferromagnetic particle in transverse magnetic field is converted to a pseudoparticle moving in effective double - well potential with the help of the effective potential description of quantum spin systems developed by ulyanov and zaslavskii . finally using the periodic instanton method we evaluate the transition amplitude , energy shift and prefactor of wkb exponential and the energy splitting of ground state and the tunneling rate for excited states induced by thermally assisted quantum tunneling are obtained 文章首先对磁性宏观量子效应的理论和实验方面作了简单介绍,然后借助于ulyanov和zaslavskii发展的一种等效势描述方法,把外磁场沿难磁化轴方向时的自旋隧穿约化成在等效双势阱中运动的粒子,利用瞬子方法给出基态能级劈裂,最后利用周期瞬子方法分别计算了隧穿幅、能级移动以及wkb前因子,从而给出由于热助量子隧穿引起的激发态的隧穿率。