Using polyethylene glycol(PEG) as internal reference, electrospray ionization(ESI)/time - of -flight mass spectrometry(TOF - MS) was developed to determine the accurate mass of the protonated molecular ions of five erythromycin analogue antibiotics.是什么意思_Using polyethylene glycol(PEG) as internal reference, electrospray ionization(ESI)/time - of -flight mass spectrometry(TOF - MS) was developed to determine the accurate mass of the protonated molecular ions of five erythromycin analogue antibiotics.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句