问题 问答题 简答题

什么是惰性气体置换法?其特点是什么?

答案

参考答案:

惰性气体置换法是指用氮气、二氧化碳等惰性气体置换管道或煤气设施中的煤气或空气。特点:惰性气体作为一种中间气体,和煤气混合不发生危险,和空气混合也不会发生危险,是一种较理想的安全可靠的置换方法。

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They may be small and not able to speak, but babies are proving their amazing cleverness. Scientists began finding infants’ skills are more than they are supposed to be.

_________

Speaking of music, babies can’t seem to resist it. Not only are their ears turned to the beats, babies can actually dance to the music.

To test babies’ dancing ability, the researchers played recordings of classical music, rhythmic beats and speech to infants, and recorded the results. They also invited professional dancers to analyze how well the babies matched their movements to the music. The babies moved their arms, hands, legs feet and heads in response to the music, much more than to the speech. The finding suggests this dancing ability is innate(与生俱来的) in humans, though the researchers aren’t sure why it becomes weaker later in their life.

Learning Quickly while Sleeping

Babies can learn even while asleep, according to a 2011 study. In experiments with 26 sleeping infants, each just 1 to 2 days old, scientists played a musical tone followed by a puff of air to their eyes 200 times over the course of a half-hour. 124 electrodes(电极) stuck on the head and face of each baby recorded brain activity during the experiments. The babies rapidly learned to foretell a puff of air upon hearing the tone, showing a four-time increase on average in the chances of tightening their eyelids in response to the sound by the end of the experiments.

As newborns spend most of their time asleep, this newfound ability might be crucial to rapidly adapting to the world around them and help to ensure their survival, researchers said.

Judging Characters Well

Judging another person helpful or harmful is crucial when choosing friends. And that ability starts early. Kiley Hamlin of Yale University showed both 6-and 10-month-olds a puppet(木偶) show, in which one character helped another climb a hill. In another scene a third character pushed the climber down. The little ones then got to choose which character they preferred. For both age groups, most babies chose the helper character. This character-judging ability could be baby’s first step in the formation of morals, Hamlin thought.

小题1:Which of the following subtitles can fill in the underlined blank?

A.Dancing to Music

B.Babies’ Amazing Abilities

C.Learning to Dance Quickly

D.Born to Dance小题2:The underlined word “it” in the third paragraph refers to______.

A.the finding

B.the dancing ability

C.the response

D.the baby小题3:The experiment with 26 sleeping infants prove that_______.

A.babies can learn even while asleep

B.babies can respond to the world around them

C.babies can tighten their eyelids in response to the sound

D.babies can communicate with others while asleep小题4:In the last experiment, most babies chose the helper character, showing that________.

A.babies can judge a person helpful or harmful

B.babies love to see a puppet show

C.babies were born to help others

D.babes have learned to help others