The electron impact mass spectra behavior of melatonin were studied by mass spectrometry through the separation of the pill, extracting of the effective part. The detecting results showed that the fragment ions of mel...The electron impact mass spectra behavior of melatonin were studied by mass spectrometry through the separation of the pill, extracting of the effective part. The detecting results showed that the fragment ions of melatonin are much more than quasimolecular ions. The fragmentation pathways of melatonin were also discussed.展开更多
In this paper, raceanisodamine are analyzed by El mass spectrometry(EIMS),their characteristic fragment ions were obtained. The fragmentation mechanism on this component was discussed. The results showed the ring of r...In this paper, raceanisodamine are analyzed by El mass spectrometry(EIMS),their characteristic fragment ions were obtained. The fragmentation mechanism on this component was discussed. The results showed the ring of raceanisodamine was crazed and characteristic ions m/z261 and base peak m/z94 were produced by losing free group CH2CH2OH, then its alcoholysis can create some ploy-ring ions such as m/z140 and m/z 156. These fragment act as the characters of raceanisodamine.展开更多
Notable features of EIMS cleavage for eight N,N diacyl adipyl dihydrazides are summarized. The sources and chemical structures of the main fragments are interpreted. All of the eight compounds give the base peak of...Notable features of EIMS cleavage for eight N,N diacyl adipyl dihydrazides are summarized. The sources and chemical structures of the main fragments are interpreted. All of the eight compounds give the base peak of m/z 143. The main fragments are from the α cleavage and its rearranging ones at the carbonyl gronp.展开更多
文摘蛋白质组学的兴起带动了质谱技术的快速发展,而质谱技术的进步则拓宽了蛋白质组学研究问题的广度.最近10年内,肽段或完整蛋白质在质谱仪中的裂解技术——电子捕获裂解(electron capture dissociation,ECD)与电子转运裂解(electron transfer dissociation,ETD)逐渐发展起来.ECD和ETD在蛋白质组学中的应用,特别是在蛋白质的翻译后修饰鉴定和"自顶而下(Top-down)"的完整蛋白质裂解研究中已经展示出了诱人的前景.对ECD和ETD的基本原理、质谱特点、仪器实现、数据解析算法与软件开发,以及在蛋白质组学中的应用进展等方面进行了比较系统全面的阐述,并对当前的研究问题、面临的技术挑战与未来的发展趋势等方面作了深入剖析.
文摘The electron impact mass spectra behavior of melatonin were studied by mass spectrometry through the separation of the pill, extracting of the effective part. The detecting results showed that the fragment ions of melatonin are much more than quasimolecular ions. The fragmentation pathways of melatonin were also discussed.
文摘In this paper, raceanisodamine are analyzed by El mass spectrometry(EIMS),their characteristic fragment ions were obtained. The fragmentation mechanism on this component was discussed. The results showed the ring of raceanisodamine was crazed and characteristic ions m/z261 and base peak m/z94 were produced by losing free group CH2CH2OH, then its alcoholysis can create some ploy-ring ions such as m/z140 and m/z 156. These fragment act as the characters of raceanisodamine.
文摘Notable features of EIMS cleavage for eight N,N diacyl adipyl dihydrazides are summarized. The sources and chemical structures of the main fragments are interpreted. All of the eight compounds give the base peak of m/z 143. The main fragments are from the α cleavage and its rearranging ones at the carbonyl gronp.
