题干

有机物 K 是一种抗惊厥药物,它们的合成路线如下(R 代表烃基):

已知:

①RCN H2O/OH RCOOH

②﹣COOH+H2N﹣→CONH﹣+H2O

分析流程并回答下列问题:

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同类题1

阅读理解

    Wouldn't it be wonderful to travel to a foreign country without having to worry about the headache of communicating in a different language?

    In a recent Wall Street Journal article, technology policy expert Alec Ross argued that, within a decade or so, we'll be able to communicate with one another via small earpieces with built-in microphones. That's because technological progress is extremely rapid. It's only a matter of time. Indeed, some parents are so convinced that this technology is imminent that they're wondering if their kids should even learn a second language.

    It's true that an increase in the quantity and accuracy of the data loaded into computers will make them cleverer at translating “No es bueno dormir mucho” as “It's not good to sleep too much.” Replacing a word with its equivalent (同义词) in the target language is actually the “easy part” of a translator's job. But even this seems to be a discouraging task for computers.

    It's so difficult for computers because translation doesn't—or shouldn't—involve simply translating words, sentences or paragraphs. Rather, it's about translating meaning. And in order to infer meaning from a specific expression, humans have to interpret a mass of information at the same time.

Think about all the related clues that go into understanding an expression: volume, gesture, situation, and even your culture. All are likely to convey as much meaning as the words you use.

    Therefore, we should be very skeptical of a machine that is unable to interpret the world around us. If people from different cultures can offend each other without realizing it, how can we expect a machine to do better? Unless engineers actually find a way to breathe a soul into a computer, undoubtedly when it comes to conveying and interpreting meaning using a natural language, a machine will never fully take our place.

同类题2

阅读理解

     I'm Leo. There is a great artist in my family. She is Lisa. Lisa likes drawing a lot. Here are her three drawings.

    There is an animal in the first drawing. It has two big eyes, a big mouth and two small ears. It has long arms and long legs. It is black and white. There are some apples in its hands. It looks very happy. What is it? I don't know, but Lisa says it is a panda.

    There is a woman in the second drawing. She is thin. She has straight blonde hair, a small mouth, a big nose and two big eyes. She looks angry. Who is she? Lisa says she is our mom. But Mom has curly blonde hair, small eyes and a small nose.

    There is an animal in the third drawing, too. Its head is an apple. Its hair and tail are leaves. It has a long mouth, and it is a banana. Its two legs are carrots. What is it? Lisa says it is a horse, but it doesn't look like a horse.

    Lisa is really a great artist, isn't she?

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同类题3

根据下列表格对应值:

判断关于x的方程ax2+bx+c=0a0的一个解x的范围是(  )

同类题4

城市中最为广泛的土地利用方式是                              

同类题5

科学研究表明:精神因素(焦虑、紧张等的心理应激)会使T细胞活性下降,对病毒、真菌感染的抵抗能力和对肿瘤细胞的监控能力下降,还间接引起机体生成抗体的能力降低.以下是其机理的简单示意图,请据图回答:

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