COMPACT AEROSOL TIME-OF-FLIGHT MASS SPECTROMETER

摘要

Among other things, methods, systems, apparatus for performing on-the-fly apportionment are described. In particular, a mass spectrometry apparatus includes an ionization laser to produce a deionization laser beam. The apparatus also includes a particle beam path that receives aerosol particles and intersects the ionization laser beam at a location where aerosol particles are desorbed and ionized by the laser beam. The apparatus also includes an ion extractor located at or near the ionization location to separate positive ions and negative ions desorbed from the aerosol particles and to direct the positive ions along a first direction of an ion path and the negative ions along a second, opposite direction of the ion path. The apparatus also includes a first reflectron located at a first side of the ion extractor, on the ion path, to reflect the positive ions along a first reflection path that deviates from the ion path. A second reflectron is located at a second, opposite side of the ion extractor, on the ion path, to reflect the negative ions along a second reflection path that deviates from the ion path and that is located on a side of the ion path that is opposite the first reflection path. In addition, a first ion detector is located on the first reflection path, to receive and detect the positive ions reflected from the first reflectron. Further, a second ion detector is located on the second reflection path to receive and detect the negative ions reflected from the second reflectron. The ion path connects the first reflectron, the ion extractor, and the second reflectron. The first reflection path connects the first reflectron and the first ion detector. The second reflection path connects the second reflectron and the second ion detector form a Z-shaped path.