When viewed under the microscope longitudinally, synthetic fibers usually appear as glass rods with either a smooth or striated surface.

纵向的显微镜下观察时，合成纤维，通常会出现一个表面光滑或横纹肌玻璃棒。

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Besides being deep and hot to handle, the metallic structures are dense and heavy, yet fragile, striated with fractures that the researchers feared would cause them to crumble like dry cake before they reached the surface.

ECONOMIST: 20,000 leagues under the sea