核磁共振几个术语的汉译英

kqlee

请将以下句子译成英语，谢谢!

$ [9 z. S$ `# g2 p

1）烷碳区，处于高场0-50。
2）取代烷碳区，50-80。包括与氧、氮、硫等相连的烷碳和炔碳。
3）芳、烯区，100-150。与1HNMR不同，13C谱中芳碳和烯碳处在同一区域，随取代基不同，δC在相当大的范围内变化。
4）羰基和叠烯区，150-200或更低场。

aggie

The signals of unsubstituted alkane carbons appear in the range of 0 to 50 ppm, while the substituted saturated carbons with O, N, or N atoms next and the alkyne carbons show up between 50 and 80 ppm. In the range of 100 to 150 ppm, lie the signals of olefinic and aromatic carbons.  Dissimilar from the 1H spectra, the signals of olefinic and aromatic carbons are in the same range but considerably diffenrent in chemical shift with the changing of the substituents. Upon 150 ppm, to the range of 200 ppm or even lower field, are the signals of carbonyls and allenes.