Ib chav sib cais huab cua (ASU) yog qhov chaw tsim khoom tseem ceeb uas ua lub luag haujlwm tseem ceeb hauv kev tshem tawm cov khoom tseem ceeb ntawm cov cua, xws li nitrogen, oxygen, thiab argon. Lub hom phiaj ntawm chav sib cais huab cua yog cais cov khoom no los ntawm huab cua, allo ...
Nyeem ntxiv