silversing的最近内容

  1. S

    need help on chemistry, please help out

    thanks for the info:D
  2. S

    need help on chemistry, please help out

    considering alpha, beta, and gamma particles
  3. S

    need help on chemistry, please help out

    Discuss why short lived radioactive isotopes pose a serious danger to humans who are directly exposed to them, but are not considered a problem for long term disposal, while very long lived radioactive isotopes are much less harmful to those directly exposed to them, but are considered a serious...
后退
顶部
首页 论坛
消息
我的