periodic system

【化学】周期系统。   detail>>

periodic inventory system

按期盘存制 定期盘存制 周期性库存系统  detail>>

periodic ordering system

定期订货系统  detail>>

periodic oxygen supply system

定期供氧系统  detail>>

periodic review system

周期检查系统  detail>>

periodic system of elements

元素周期系  detail>>