MFC GAS Feedthrough Numbers? Mass O2 needed? (It means: Protection against Reoxidation needed. Oil Free Pump needed. High speed and ultra-high vacuum Pump needed.是什么意思_MFC GAS Feedthrough Numbers? Mass O2 needed? (It means: Protection against Reoxidation needed. Oil Free Pump needed. High speed and ultra-high vacuum Pump needed.在線翻譯_英語_讀音_用法_例句