Hair irons can take many shapes but are essentially clips or rods with heated surfaces.

烫发器可以帮你打造很多发型，但本质上它是加热过的夹子或铁棒。

In a Purdue University lab, a movable flat hair iron goes over a hair strand while an infrared microscope measures the changes in the hair's structure.

普渡大学在一间实验室中, 一个可移动烫发器在一缕头发间通过, 而上面的红外显微镜则检测头发的结构变化。