It introduces the method of preparation,research of performance and calculation of uncertainty of mixed gas reference material of tetrafluoromethane,nitrous oxide and hexafluoride in helium.是什么意思_It introduces the method of preparation,research of performance and calculation of uncertainty of mixed gas reference material of tetrafluoromethane,nitrous oxide and hexafluoride in helium.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句