The mass spectra of ureide-type noncyclic polyethers with 2(3H)-benzoxazolone as end groups were studies.
研究了以2（3H）-苯并唑酮为端基、具有酰脲结构的非环多醚化合物的质谱。
Mass Spectra
英语例句库
RESULTS The chlortetracycline's epimer, tetracycline and its epimer, as impurities in chlortetracycline have been determined by the liquid chromatogram and its first order mass spectrum.
结果得到金霉素样品液相色谱图以及液相色谱峰对应的一级质谱图。对谱图进行分析归纳,推测金霉素样品中含有四环素、差向异构四环素和差向异构金霉素杂质组分。
英语百科
Mass spectrum
（重定向自Mass Spectra）
A mass spectrum is an intensity vs. m/z (mass-to-charge ratio) plot representing a chemical analysis. Hence, the mass spectrum of a sample is a pattern representing the distribution of ions by mass (more correctly: mass-to-charge ratio) in a sample. It is a histogram usually acquired using an instrument called a mass spectrometer. Not all mass spectra of a given substance are the same. For example some mass spectrometers break the analyte molecules into fragments; others observe the intact molecular masses with little fragmentation. A mass spectrum can represent many different types of information based on the type of mass spectrometer and the specific experiment applied; however, all plots of intensity vs. mass-to-charge are referred to as mass spectra. Common fragmentation processes for organic molecules are the McLafferty rearrangement and alpha cleavage. Straight chain alkanes and alkyl groups produce a typical series of peaks: 29 (CH3CH2), 43 (CH3CH2CH2), 57 (CH3CH2CH2CH2), 71 (CH3CH2CH2CH2CH2) etc.