Muag Kub

Peb yog cov chaw muab khoom zoo ntawm cov khoom siv raw thiab cov khoom ua tiav ntawm tungsten, molybdenum, tantalum, thiab niobium refractory cov ntaub ntawv. Peb cov khoom feem ntau yog cov txheej txheem nqus tsev, cov cub tawg kub siab, photovoltaic, semiconductors, thiab lwm yam lag luam. Peb zoo siab los pab cov neeg siv khoom daws teeb meem, thov hu rau peb tam sim ntawd.