the testing of metals and chemicals for quality, often to see how pure they are含量测定
Word OriginMiddle English (in the general sense ‘testing, or a test of, the merit of someone or something’): from Old French assai (noun), assaier (verb), variant of essai ‘trial’, essayer ‘to try’ based on late Latin exagium ‘weighing’, from the base of exigere ‘ascertain, weigh’.