茶多酚是目前尚不能人工合成的纯天然、多功能、高效能的抗氧化剂和自由基净化剂。其中

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问题:

茶多酚是目前尚不能人工合成的纯天然、多功能、高效能的抗氧化剂和自由基净化剂。其中没食子儿茶素(EGC)的结构如图所示。关于EGC的下列叙述中正确的是

[ ]

A.分子中所有的原子共面

B.1 mol EGC与4 mol NaOH恰好完全反应

C.易发生氧化反应和取代反应,能发生加成反应

D.遇FeCl3溶液不发生显色反应

考点:其他不常见有机物(杂环、难命名的有机物、K粉等)
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其诊断为

A.产后伤食腹痛
B.产褥感染腹痛
C.产后血晕
D.产后郁冒
E.产后腹痛

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甲乙两人做的零件个数之比是5:3,甲比乙多做140个,两人各做多少个零件?

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什么是EDI?EDI标准有哪些?其目的是什么?作用表现在哪些方面?

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工程项目的地质、水文、气候是属于施工环境中的()的内容。

A.劳动作业环境

B.自然环境

C.社会环境

D.地理环境

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I shouldn’t let it bother me. It really doesn’t matter anyway. But it does bother me ! All those people are preparing to (21) a new century, a new millennium (千年) as well. And it just isn’t (22) !
Most of us schedule our lives by the Gregorian (23) . Our years are measured from the (24) of Christ. The first year of the first century is 1, or 1 A.D. The last year of that century is the year 100. Simple Yes! A century is 100 (25) long. A millennium is 1,000 years long, which is (26) ten centuries.
Since the last year of the first century is the year 100, the first year of the (27) century is 101. Follow that pattern, century by century and you’ll get my (28) . The year 2000 is the last year of the twentieth century. After all, (29) thousand means twenty hundreds. Twenty hundred years means twenty centuries. The year 2000 is the (30) , the final, the one that’s still here, year of the twentieth century!!!!
I know, I’m getting too (31) . But it isn’t fair, While most people will really be enjoying this coming (32) celebration, those of us in the know will be yawning. Everyone else will be (33) for the new millennium and we’ll be saying, "It’s not until next year."
I don’t agree with the (34) , "Ignorance is bliss." But in this case, perhaps it’s (35) .

A.hungry

B.handsome

C.inaccurate

D.excited

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