Hauv kev tsim khoom, cov khoom siv ua lub luag haujlwm tseem ceeb hauv kev txiav txim siab qhov zoo, kev ua tau zoo, thiab kav ntev ntawm cov khoom. Ntawm cov ntaub ntawv no, kev ua haujlwm siab engineering plastics tau tshwm sim los ua kev hloov pauv kev ua si. Tsis zoo li cov khoom siv yas, cov khoom siv siab tshaj no muaj tshwj tsis yog ...
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