题干

始祖鸟烯(Pterodactyladiene)形状宛如一只展翅飞翔的鸟,其键线式结构表示如下,其中R1、R2为烷烃基。则下列有关始祖鸟烯的说法中正确的是(  )

A:始祖鸟烯与乙烯互为同系物

B:若R1=R2=甲基,则其化学式为C12H16

C:若R1=R2=甲基,则始祖鸟烯的一氯代物有3种

D:始祖鸟烯既能使酸性高锰酸钾溶液褪色,也能使溴水褪色,且两反应的反应类型是相同的

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C

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    We all know the feeling: looking at the computer screen, pretending to be interested in our homework, even though we really feel bored. But such feelings may soon be at an end, says Dr. Harry Witchel, head of the Essex Medical School. He believes that computers of the future will notice when people feel bored and even take action to stopit.

    Before you get concerned, the machine won't be reading your mind. It will be observing the many movements you make while using a computer. It's not interested in the big movements needed to use the machine — like moving a mouse or touching a screen — but small, barely noticeable movements like closing your eyes, moving in your seat or rubbing your face. Witchel calls these “boredom movements" and says they show how interested the person is in what they are reading or watching. The higher the interest level, the less movement!

    To test his theory, Witchel invited 27 people to perform various computer-based tasks. The activities ranged from playing online games (an interesting task) to reading documents like government laws that most people would find boring.

A special video camera followed the participants' movements as they completed each task. Just as the researcher expected, the “boredom movements" greatly decreased, by as much as 42%,when the subjects were very interested in what they were reading or seeing.

    Fortunately, Dr Witchel isn't planning to use his results to create machines that report students who are not paying attention at school. Instead, he wants “movement sensing” technology to be built into future computers in order to improve students' computer-based learning experience.

    The scientist says that by measuring the students' interest level as they work, educators will be able to adjust their materials in real-time to keep students focused. Witchel also believes that the technology can provide filmmakers with honest audience opinions and in the future, help to develop more intelligent robots.