从螺旋理论看，芳香轮烯和非芳香轮烯都是内消旋体和外消旋体的混合物，故都不呈现旋光性。
In the light of the helix theory, aromatic annulenes and non-aromatic annulcncs are all the mixture of the mesomer and raceme, so they haven't opticity activeity.
指出了内消旋体消旋原因传统解释的不合理性。
For the reason why optical activity of mesomer is counteracted classical answer was not convincing.
利用内消旋丙交酯在水中水解的速度大于其它丙交酯的特点，用水洗和四次重结晶相结合的提纯方法，获得了高纯的L-丙交酯。
Using the difference of the hydrolysis speed in the water between meso-lactide and other lactides, high pure L-lactide was obtained by water washing-four times recrystallization.
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