Place the tester adapter over the opening.把试验器连接装置放在加油口上.The enamel surface microhardness was measured by a Leitzs microhardness tester.采用维氏显微硬度仪测定经饮料浸泡后牙釉质表面显微硬度的变化.Tester must read all zeroes.检测器读数必须都为零.Durometer harde...