In a semiheavy water molecule, one hydrogen atom (H) is replaced with a heftier version called deuterium (D).

在半重水的水分子中，一个氢原子（H）被一个称之为氘（D）的氢原子的同位素所取代。

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On a molecular level, D-tagatose is structurally identical to D-fructose, except for an inversion of the hydroxyl and hydrogen groups at the fourth carbon atom.

塔格糖是果糖的“差向异构体”，在分子水平上，除了第四个碳原子上的羟基和氢基团倒置外，D -塔格糖与D -果糖的结构是一样的。

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There is a chiral carbon atom in the EAMP's molecule and it has been proved that the S-EAMP has higher biological activity than that of the D-EAMP.

它的分子结构中有一手性碳原子，大量研究结果证明其左旋光学异构体的生理活性比右旋异构体要高很多。

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So, I'm asking very specifically about radial nodes here, how many radial nodes does a hydrogen atom 3 d orbital have?

我问的是径向节点，这里3d轨道的径向节点有多少个？

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Back in 1959 American physicist Richard Feynman famously predicted that we'd be creating atom sized machines in the future.

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If any four atoms, let say, atoms A, B, C and D, would be selected to test the decay, atom A would have much lesser chance to respond to decay due to the existence of atoms B, C and D.

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If you'd like more power than an Atom processor while keeping the price in check, however, the S1082 could still be a solid choice when it ships to the US in February.

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