11、硅胶吸附薄层鉴定下列化合物(展开剂:CHCl3:EtOAC:水=为 4:1),请判断 Rf值的

11、硅胶吸附薄层鉴定下列化合物(展开剂:CHCl3:EtOAC:水=为 4:1),请判断 Rf值的大小:OOH OOHOHOHO gluOOH OOHOHOH

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5、某中药主要含有下列五种成分,用下述工艺进行提取分离。

5、某中药主要含有下列五种成分,用下述工艺进行提取分离。

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Mary was such a hardworking student that she soon

Mary was such a hardworking student that she soon came out first in the class.

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58.在浓缩的水提取液中,加入一定量乙醇,可以除去下述成分,除了 A.树脂 B.淀粉 C.树胶 D.

58.在浓缩的水提取液中,加入一定量乙醇,可以除去下述成分,除了 A.树脂 B.淀粉 C.树胶 D.粘液质 E.蛋白质

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The author.s attitude toward examination is ______

The author.s attitude toward examination is ________. A) resentful B) negati

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