Raws li peb txhua tus paub, cov khoom siv yog lub hom phiaj ntawm cov khoom siv hluav taws xob ceev ceev.Muaj ntau qhov sib piv ntawm cov khoom siv, xws li hlau, alloys, oxides thiab lwm yam.Kev lag luam siv kuj txawv, thiab lawv tau siv dav.Yog li dab tsi yog cov hom phiaj hlau?Ntau npaum li cas...
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