Preca普雷卡PREabbr.Petroleum Refining Engineer炼油工程师preconceived track预定轨迹precrystallization前结晶Premarket Approval售前许可precondition input预处理输入preocellar bristle单眼前鬃precooling methods预冷方式pre frontal cortex前额叶prefetch processor预取处理机pre-stowage plan配载图preheating section预热段