题干

当光束通过下列分散系时,能产生丁达尔效应的是(  )


A:豆浆

B:食盐水 

C:碘酒

D:蔗糖水

上一题 下一题 0.0难度 选择题 更新时间:2019-06-09 09:02:58

答案(点此获取答案解析)

A

同类题4

       Bringing a giraffe into the world is a tall order. A baby giraffe is born 10 feet high and usually lands on its back. Within seconds it rolls over its legs under its body. Then the mother giraffe rudely introduces its children to the reality of life.
       In his book, A View from the Zoo, Gary Richmond describes how a new-born giraffe learns its first lesson.
       The mother giraffe lowers her head long enough to take a quick look. Then she puts herself directly over her child. She waits for about a minute, and then she does the most unreasonable thing. She throws her long leg and kicks her baby, so that it's sent sprawling(四脚朝天).
When it doesn't get up, the process is repeated again and again. The struggle to rise is important. As the baby giraffe grows tired, the mother kicks it again. Finally, it stands for the first time on its shaky legs. Then the mother giraffe kicks it off its feet again. Why? She wants it to remember how it got up. In the wild, a baby giraffe must be able to get up as quickly as possible to stay with its group, where there’s safety.
        Another writer named Irving Stone understood this. He spent a lifetime studying greatness, writing stories about such men as Michelangelo, Vincent van Gogh, Sigmund Freud, and Charles Darwin.
       Stone was once asked if he had found something that runs through the lives of all these great people. He said, “I write about people who sometime in their life have a dream of something. They're beaten over the head, knocked down and for years they get nowhere. But every time they stand up again. And at the end of their lives they've realized some small parts of what they set out to do .”

同类题5

以下是中共一大到七大时党员人数简表,该数据直接反映了        (   )
代表大会
1921一大
1922二大
1923三大
1925四大
1927五大
1928六大
1945七大
党员人数
50人
195人
420人
994人
5.7万人
4万人
121万人