1.Siv raws li cov khoom siv hluav taws xob carbon thiab graphite cov khoom siv dav siv los ua cov khoom siv hluav taws xob hauv kev tsav tsheb thiab kev tsim khoom, xws li cov hlua hluav taws xob thiab cov txhuam hniav.Tsis tas li ntawd, lawv kuj tau siv los ua carbon rods hauv roj teeb, teeb pom kev zoo, lossis electro optical carbon rods th ...
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