Using the perturbative method the asymptotic solution of the corresponding model is obtained.

利用摄动方法求出了相应模式的渐近解。

The perturbative methods for positron-atom scattering omitted Ps formation and ionization channels.

微扰的方法在正电子与原子的三射中忽略了电子偶素形成和电离通道；

Chapter 1 begin with an introduction and overview of the computations of perturbative scattering amplitudes.

第一章是关于微扰散射振幅计算的导论和概述。

Studying QCD vacuum properties and non-perturbative QCD is a very important issue for strongly interacting processes.

研究QCD真空性质和非微扰QCD对于强相互作用过程来说是一个非常重要的问题。

Then the perturbative description of the interaction between a single electron and the laser field can be replaced by the tunneling ionization.

此时单个电子与场相互作用的微扰描述可以用隧穿描述取代。