nucleus
nucleus 英 [ˈnju:kliəs] 美 [ˈnukliəs]
n. 核，核心；原子核
名词复数:nuclei
- A nucleus is often called the brain, or control center, of a eukaryotic cell (that is, a cell with a nucleus).
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- n. 核，核心；原子核
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1. We have a helium nucleus and one electron.
我们有一个氦核和一个电子。
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2. But the second factor is how far away we are from the nucleus.
但还有第二个因素,那就是我们离原子核有多远。
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3. Because we know as we go to infinity, even though the density gets smaller and smaller and smaller, we still have electron density very far away from the nucleus.
因为我们知道即使到了无穷远处，尽管电子密度会变得非常非常非常小，但我们仍然有一定的电子密度，无论离原子核多远。
- nucleus (n.) 1704, "kernel of a nut," 1708, "head of a comet," from Latin nucleus "kernel," from nucula "little nut," diminutive of nux (genitive nucis) "nut," from PIE *kneu- "nut" (source also of Middle Irish cnu, Welsh cneuen, Middle Breton knoen "nut," Old Norse hnot, Old English hnutu "nut"). General sense of "central part or thing, about which others cluster" is from 1762. Use in reference to cells first recorded 1831. Modern atomic meaning is 1912, first by Ernest Rutherford, though theoretical use for "central point of an atom" is from 1844, in Faraday.
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