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问题 选择题

具有显著抗癌活性的10- 羟基喜树碱的结构如图所示。下列关于10- 羟基喜树碱的说法正确的是    

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A．分子式为C20H16N2O5

B．不能与FeCl3溶液发生显色反应

C．不能发生酯化反应

D．一定条件下，1 mol该物质最多可与1 mol NaOH反应

答案

答案：A

单项选择题

在寒冷地区，基础的埋置深度应( )。

A．在冰冻线以上

B．在冰冻线以下

C．在冰冻线处

D．与冰冻线无关
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问答题

What is a novel I say: an invented story. At the same time a story which, though invented, has the power to ring true. True to what True to life as the reader knows life to be or, it may be, feels life to be. And I mean the adult, the grown-up reader. Such a reader has outgrown fairy tales, and we do not want the fantastic and the impossible. So I say to you that a novel must stand up to the adult tests of reality. You may say:”If one wants truth, why not go to the literally true book Biography or documentary, these amazing accounts of amazing experiences which people have.” Yes, but I am suggesting to you that there is a distinction between truth and so-called reality. The novel does not simply recount experience. And here comes in what is the actual livening spark of the novel: the novelist’s imagination has a power of its own. It does not merely invent, it perceives. It intensifies, therefore it gives power, extra importance, and greater truth to what may well be ordinary and everyday things.

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