The firstthree positions were filled by medical inventions or discoveries,the X-ray machine being followed by the discoveries of penicillinand the DNA double helix structure。
排在榜单三甲位置的发明都是医学领域的重大发明或发现。紧随X光机之后的是盘尼西林(青霉素)的发明，以及DNA双螺旋结构的发现。
Whether we really understand DNA is debatable, but Francis Crick and James D. Watson published the first of many papers describing the double helix structure on this day in 1953.
我们是否真正了解了DNA仍值得商榷，但1953年的这一天，弗朗西斯·克里克(Francis Crick)和詹姆斯·d·沃森发表了系列论文的第一篇，阐述了DNA的双螺旋结构。
From the STMimages, we could see clearly the helix pitch and helix diameter of helix structure.
由STM图象中我们能清晰地观察到螺旋结构的螺距与螺径。
From the STMimages, we could see clearly the helix pitch and helix diameter of helix structure.
由STM图象中我们能清晰地观察到螺旋结构的螺距与螺径。
应用推荐