The main method of separation used in refineries is fractional distillation although further processing is normally required to produce marketable petroleum products.
分离石油主要采用的方法就是分馏，然后通过深加工才能得到可以销售的石油产品。
2
We derive the analytic solution of the non-homogeneous fractional diffusion-wave equation under the mixed boundary conditions using the method of separation of variables.
利用分离变量方法导出了在混合边界条件下的非齐次分数阶扩散-波动方程的解析解。
3
In fractional distillation, that part of the distillate which may be returned to the column to assist in making a better separation into desired fractions.