| GC-TOF MS with separation ability of gas chromatograph (GC) and the qualitative ability of time of flight mass spectrometer (TOF MS),leads the development of hyphenated technique of GC-MS to the application field of fast detection and complex sample analysis .It has been paid more and more attention of analyst and investor Nowadays ,technique of gas chromatograph in our country has become more and more mature, in addition, the research of mass spectrometer has been increasingly developing because of the financial support of government . Under this background, research on the hyphenated technique of GC-TOF MS is necessary and reasonable.The essay ,aimed to advance the process of GC-TOF MS nationalization, carried out the exploration of homemade GC-TOFMS from three aspects. Firstly ,an efficient electron impact ion source has been designed and tuned. Tuning curves of parameters have been obtained to find out the influence of the ion source parameters on the performance of instrument .And some phenomenon which emerged during the parameter tuning was researched and explained. Secondly,A new interface for combining GC and TOF MS were designed which performed high hermetic ability and temperature stability .The matching of gas flow rates and vacuum system was carefully considered and based on the consideration ,a new structure of vacuum system were designed .Thirdly,the platform of GC-TOF MS system was established. Some experiments were carried out to optimize the instrumental performance through trying different working condition .Based on the result of the experiment ,the sensitivity of the homemade GC-TOF MS could be expressed as followed:50pg pentadecane ,the ratio of signal to noise(S/N) equals to 100:1.The resolving power of mass spectrum could reach 1500 at m/z=75Da.Compared with the standard mass spectrum in the NIST library ,the march factor reached 760.The performance of the GC-TOF MS described above proves that the instrument has certain qualitative and quantitative ability.
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