To establish a new GC-MS/MS method for quantitative detection of 22 kinds of pesticide in fruit and vegetable including organic phosphorus,carbamate & pyrethrin etc.Working was performed by Xcalibur software with ...To establish a new GC-MS/MS method for quantitative detection of 22 kinds of pesticide in fruit and vegetable including organic phosphorus,carbamate & pyrethrin etc.Working was performed by Xcalibur software with multitask mode.We Carried on qualitative and quantitative analysis to mass spectrum of MS/MS in order to obtained a credible experiment result.This method is sensitive and accurate,it is suitable for determination of multifarious pesticide residues.展开更多
Biological mass spectrometry has received a great progress in recent years.The osteopontin(OPN) isolated and purified from the human milk was studied by HPLC using SCX and C4 columns.After hydrolyzing the purified OPN...Biological mass spectrometry has received a great progress in recent years.The osteopontin(OPN) isolated and purified from the human milk was studied by HPLC using SCX and C4 columns.After hydrolyzing the purified OPN sample by trypsin,the correlative polypeptide fragments GDSVVYGLR and QNLLAPQTLPSK were obtained by FT-ICR-MS.It showed that the method of nano-spray HPLC combined with FT-ICR-MS and Mascot search was very efficient for the analysis of the purified OPN and its polypeptide fragments.Further study provides more academic theories of their different modifications and the relative bioactivities.展开更多
【意义】大环烷烃是一类具有单环结构而环碳数较大(n>10)的饱和脂肪烃类化合物,在油页岩、原油、土壤及高等植物中均有检出,其具有确切的生物母源信息,可以清晰地指示样品的原始沉积环境。大环烷烃碳数范围不固定,与长链烷基烯烃、...【意义】大环烷烃是一类具有单环结构而环碳数较大(n>10)的饱和脂肪烃类化合物,在油页岩、原油、土壤及高等植物中均有检出,其具有确切的生物母源信息,可以清晰地指示样品的原始沉积环境。大环烷烃碳数范围不固定,与长链烷基烯烃、烷基环己烷等化合物相比,不仅在色谱上具有相同的等间距流出特征,而且它们的质谱分子离子(C_(n)H_(2n))和特征碎片离子(m/z 97、111、125)也一模一样,极易造成误判,亟须对其结构特征进行精准厘定。【进展】系统梳理了相关的文献,并以澳大利亚悉尼盆地藻烛煤(torbanite)为对象,分离纯化单体化合物后完成核磁(Nuclear Magnetic Resonance,NMR)结构解析;类比环己烷断裂模式,提出三条质谱裂解途径,完整阐释了其特征碎片的生成机制;进一步归纳了大环烷烃可能的生物合成路线。【结论与展望】NMR结构鉴定表示大环烷烃具有特殊的单体饱和环烷烃结构。Torbanite中丛粒藻来源的大环烷烃类化合物最初的生物前体可能是长链的油酸,经长链不饱和聚醛中间体最终环化而成。未来可以逐步完善高等植物来源的大环烷烃的生物合成途径,并对其相关比值参数进行归纳总结以应用于实际地质样品中。展开更多
文摘To establish a new GC-MS/MS method for quantitative detection of 22 kinds of pesticide in fruit and vegetable including organic phosphorus,carbamate & pyrethrin etc.Working was performed by Xcalibur software with multitask mode.We Carried on qualitative and quantitative analysis to mass spectrum of MS/MS in order to obtained a credible experiment result.This method is sensitive and accurate,it is suitable for determination of multifarious pesticide residues.
文摘Biological mass spectrometry has received a great progress in recent years.The osteopontin(OPN) isolated and purified from the human milk was studied by HPLC using SCX and C4 columns.After hydrolyzing the purified OPN sample by trypsin,the correlative polypeptide fragments GDSVVYGLR and QNLLAPQTLPSK were obtained by FT-ICR-MS.It showed that the method of nano-spray HPLC combined with FT-ICR-MS and Mascot search was very efficient for the analysis of the purified OPN and its polypeptide fragments.Further study provides more academic theories of their different modifications and the relative bioactivities.
文摘【意义】大环烷烃是一类具有单环结构而环碳数较大(n>10)的饱和脂肪烃类化合物,在油页岩、原油、土壤及高等植物中均有检出,其具有确切的生物母源信息,可以清晰地指示样品的原始沉积环境。大环烷烃碳数范围不固定,与长链烷基烯烃、烷基环己烷等化合物相比,不仅在色谱上具有相同的等间距流出特征,而且它们的质谱分子离子(C_(n)H_(2n))和特征碎片离子(m/z 97、111、125)也一模一样,极易造成误判,亟须对其结构特征进行精准厘定。【进展】系统梳理了相关的文献,并以澳大利亚悉尼盆地藻烛煤(torbanite)为对象,分离纯化单体化合物后完成核磁(Nuclear Magnetic Resonance,NMR)结构解析;类比环己烷断裂模式,提出三条质谱裂解途径,完整阐释了其特征碎片的生成机制;进一步归纳了大环烷烃可能的生物合成路线。【结论与展望】NMR结构鉴定表示大环烷烃具有特殊的单体饱和环烷烃结构。Torbanite中丛粒藻来源的大环烷烃类化合物最初的生物前体可能是长链的油酸,经长链不饱和聚醛中间体最终环化而成。未来可以逐步完善高等植物来源的大环烷烃的生物合成途径,并对其相关比值参数进行归纳总结以应用于实际地质样品中。
