Tus nqi nce yog cov tsos mob; kev txhim kho yog qhov tseem ceeb.

Qhov kev nce siab nyob rau hauv cov nqi tungsten tam sim no tsis yog ib qho kev hloov pauv ntawm lub voj voog, tab sis qhov "rov ntsuam xyuas ntawm kev lag luam tus nqi" thiab "siv- sab purification."

Nqe tau dhau los ua qhov kev tshuaj ntsuam xyuas ncaj qha tshaj plaws, tshem tawm cov tuam txhab uas cia siab rau cov khoom siv pheej yig, muaj cov ntsiab lus thev naus laus zis tsawg, thiab tus nqi ntxiv tsawg.

Qhov kev ntxhov siab no tau hloov mus rau kev txhawb siab, yuam kom tag nrho kev lag luam dhia mus rau qhov siab -kev tsim khoom kawg: cov tuam txhab yuav tsum tsim kho thev naus laus zis los txhim kho cov khoom siv rov ua dua tshiab, ua kom zoo dua cov khoom siv, thiab kov yeej cov kev sib tw hauv siab - cov ntawv thov kawg txhawm rau kom nce foothold hauv kev lag luam yav tom ntej uas lawv yuav muaj kev cuam tshuam ntau dua.