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。

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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。

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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.

在分馏中被送回塔内促进更好分离成所需馏分的那部分馏分油。

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