TA的每日心情 | 慵懒 2018-11-21 09:39 |
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本帖最后由 enti 于 2019-1-4 04:55 编辑 0 c& h9 c- }2 P2 u
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F' W- B! q* V' N- E9 C# LThis required uranium, a metal, to be converted into a gas, uranium hexafluoride, that could be streamed through the barrier, its surface designed to allow U-235 to pass through more readily. But to make uranium hexafluoride required combining uranium with the element that most chemists still feared: fluorine. And with no practical way to contain either fluorine or uranium hexafluoride, which was also as dangerous and reactive, the undertaking seemed like a long shot. Even Urey was skeptical. In short, what he needed was a class of never-built-before materials made to suit the harshest industrial environment yet conceived, and produced at a scale thought unfathomable.
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1. yet 这里是哪种意思?
m' P/ ]; [" ~ -- 修饰harshest?
2 A+ Q# P2 e$ y- k$ M# g. { -- 修饰conceived?4 W% o" K+ `, o
% A" M4 f) u! [' i- E/ ]2 . produced at a scale 是什么意思?& p7 T, ^! u( h
-- 修饰 material 而不是 environment 是因为那个逗号么?
) T- p% K4 ? X -- 这种材料能(在数量上)大规模生产(数量) / 这种材料能(在各种环境下)大范围生产? |
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