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顶空-气相色谱法进展 总被引:17,自引:0,他引:17
回顾了顶空采样气相色谱分析法在复杂基质中挥发性成分中的应用.总结并详述了顶空分析的三种重要模式-介绍了顶空分析的相关原理和整个顶空分析系统的参数优化过程.综述了顶空.气相色谱分析在生物样本中挥发性有机物的测定、药品中有机残留溶剂的检测、聚合材料中挥发性有机物的分析、环境中有害的有机挥发性物质分析、挥发油分析和烟草分析等方面的进展. 相似文献
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利用离子阱质谱的原理和特点,研究了小分子醇、醚、胺、醛、酮等有机化合 物(分子量小于200)在离子阱里的分子离子反应,总结了反应特点和规律,并把 它归类为自身化学电离(SCI)反应。以丁酮、丙烯醇为例,采用FTMS对反应产物 离子进行准确质量测定,验证了它们各自的分子离子反应结果。另外,把该类化合 物(30个)SCI反应的质谱图与NIST98库中的标准EI质谱图进行了比较,建立了 SCI质谱图库,提高了在离子阱质谱上对这类小分子化合物定性分析的准确率。 相似文献
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Twenty common amino acids have been analyzed successfully by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) using carbon nanotubes as matrix. From the spectra, little or no background interference or fragmentation of the analytes has been observed. This method was also applied to the analysis of amino acid mixture successfully. Carbon nanotubes have some features such as large surface area to disperse the analyte molecules sufficiently and prevent the sample aggregation and strong ultraviolet absorption to transfer energy easily to the analyte molecules. The present method has potential application for the rapid and sensitive analysis of amino acids and their mixture. 相似文献
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High performance liquid chromatography (HPLC) and electrospray ionization mass spectrometry (ESI-MS) have been utilized to analyze the synthesized 2-(2-arylaminomethylphenoxy)pyrimidine derivatives, which are a new kind of environmentally benign herbicides and have passed the temporary pesticide registration. The identification of main product and impurities has been achieved according to the UV and mass spectra. Moreover, one impurity, introduced by the raw material in the last step of the synthetic route, was identified by GC-MS analysis. It can be concluded that the combination of chromatography and mass spectrometry, including LC-MS and GC-MS, provided a vital tool of the pesticide science. 相似文献
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MALDI/FTMS中碰撞衰减机理对准确质量校正的影响 总被引:1,自引:0,他引:1
Collisional damping affects the relationship between ion mass and effective cyclotron frequency in Fourier transform mass spectrometry. The exact mass calibration equation(m/z=A/f+(mneutral/m^^+mneutral)k+B/f(f+(mneutral/m^^+mneutralk))was therefore derived from the characteristic equation of system model, force=m(dv/dt)=qE-qv×B0-ξv,a frictional damping force), in which k is amended by the shift of observed frequency of matrix ion or other known ion in external calibration. The mass obtained by the amended calibration equation is therefore immune to collisional damping and space-charge effects on mass accuracy. The relative errors of ion mass measured were all less than 2×10^-6. 相似文献
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采用顶空-气相色谱-四极质谱法和顶空-气相色谱-飞行时间质谱法对鱼腥草挥发性成分进行检测,运用保留指数结合准确质量测定,分别从鱼腥草茎和叶中鉴定出49、39种挥发性组分,并采用峰面积归一化法测定各组分的相对含量。鱼腥草茎和叶中的挥发性成分差别较大。鱼腥草茎以α-蒎烯(12.24%)、β-蒎烯(22.42%)、月桂烯(11.98%)、乙酸冰片酯(10.97%)、甲基正壬酮(10.83%)为主要成分,而鱼腥草叶则以月桂烯(39.48%)、(Z)-β-罗勒烯(26.52%)、癸醛(10.35%)、桧烯(4.43%)、甲基正壬酮(2.44%)为主。结合保留指数和准确质量测定能显著提高质谱定性的准确性,有利于解决质谱检索时定性不确定的问题。 相似文献