题干

科技馆是社会大课堂实践活动的重要基地,其中“物质之妙”展区蕴含着丰富的化学知识.请回答题.

A为展区中展示的金刚石的微观结构模型,构成金刚石的基本微粒是____ .

B介绍了14C测年法,14C是质子数为6,中子数为8的碳原子,该原子中核外电子数为____ .

C介绍了化学家门捷列夫,其在化学史上的突出贡献是____  (填数字序号).

①提出分子学说 ②编制元素周期表  ③提出近代原子学说.

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碳原子,6,②

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    Watching a 3D movie can more than double the concentration powers and cognitive(认知) processing of children, a new research claims.

    A study made by visual technology firm RealD and led by child psychologist Dr. Richard Woolfson suggests that children aged between 7 and 14 experienced twice the cognitive processing speed and performed better in testing after watching 20 minutes of a 3D film. This is despite suggestions that attention spans(时期) in children have shortened in the last decade due to unlimited to access to entertainment, including on-demand TV, gaming and social media. A 2015 study claimed that watching 3D content had a similar effect to brain-training exercises.

    Consumer psychologist Mr. Fagan said that the increased stimulation(刺激) found in watching something in 3D "exercised" the brain and improved performance in the short term. "3D films can play the role of ‘brain-training' games and help to make children ‘smarter' in the short term," he said. "The shortening of response times after watching 3D was almost three times as big as that gained from watching 2D; in other words, 3D helps children process aspects of their environment more quickly. This is likely to be because 3D is a mentally stimulating experience which ‘gets the brain's juices flowing'."

    The experiment saw children given a range of cognitive tests before watching 20 minutes of a movie in either 2D or 3D and being tested again. The results showed those who saw the 3D content reacted faster and performed bettering the second round of testing. Mental engagement also rose by 13% among 3D watchers. Child psychologist Dr. Woolfson added that “supportive parenting” and regularly listening to classical music can also aid a child's memory.