在一些工业地区，马匹正沿着金属轨道拉着满载货物、带法兰轮子的马车；固定的蒸汽机在工厂和矿井里噗噗作响。

In some industrial regions, heavily laden wagons, with flanged wheels, were being hauled by horses along metal rails; and the stationary steam engine was puffing in the factory and mine.

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一个参加者把一节绳索系在我的背带上，另一端系在我头顶金属轨道的滑块上。

An attendant attached one end of a rope to my harness and the other end to a sliding element in a metal track above my head.

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然后，为了提高STM的分辨率和对分子轨道相的灵敏度，研究者们固定住一个一氧化碳分子在STM金属尖端。

Then, to improve the resolution of the STM and make it sensitive to the phase of the molecule's orbital, the researchers stuck a single carbon monoxide molecule on the metal STM tip.

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And in the second half of this course, talk to us about transition metals in depth, and that's when we'll really delve into d orbitals.

在这个课程的后半部分，会深入的讲到，过渡金属，这时候，你们可以研究d轨道。

麻省理工公开课 - 化学原理课程节选