【摘要】 在研究多相催化反应中 ,建立和发展了一套在线高灵敏的共振增强多光子电离 飞行时间质谱检测系统。采用光纤作为传输介质 ,消除了激光在电离池内的吸收 ;自制了高输入阻抗的电荷灵敏放大器 ,提高了信号的稳定性 ;改进了飞行时间质谱仪中脉冲阀的进气方式 ,减少了死区 ,实现了质谱的快速采样。实验结果证明与传统的催化检测仪器相比 ,本系统具有灵敏度和采样率高 ,在线实时检测等特点。更多还原

【Abstract】 A high sensitive on line detection system for heterogeneous catalysis was built and developed, in which both of the resonance enhanced multi photon ionization and time of flight mass spectroscopy (TOF MS) were used. The optical fiber was adopted to transmit laser and eliminate the laser adsorption in ionization chamber; the home made high input impedance circuit was applied to improve the signal stability ; fast sampling was carried out by changing gas inlet of TOF MS to reduce the dead volume of pulse valve. The results indicates this system has higher sensitivity and sampling frequency than traditional detection apparatus for heterogeneous catalysis.更多还原