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Pulsed triple ionization source

Like sector analyzers, quadrupole analyzers are well suited for continuous ion sources such as ESI, but are not well-suited for pulsed ionization methods. Quadmpole mass spectrometers are generally substantially cheaper and smaller than sector instruments and Qq-TOFs. They are very often used in combination with GC and LC, and single or triple quadmpole mass filters are very common benchtop instruments for routine measurements. [Pg.51]

Figure Bl.10.11. Electron impact double ionization triple coincidence experiment. Shown are the source of electrons, target gas, three electron detectors, one for the scattered electron and one for each of the ejected electrons. Two time differences, and 23, are recorded for each triple coincidence, is the difference in arrival times of ejected electron 1 and the scattered electron 23 is the difference in arrival times of ejected electron 2 and the scattered electron. Two sets of time-to-amplitude converters (TACs) and pulse height analysers/analogue-to-digital converters (PHA/ADC) convert the times to binary encoded numbers that are stored in the memory of a computer. The data can be displayed in the form of a two-dimensional histogram (see figure B 1.10.12). Figure Bl.10.11. Electron impact double ionization triple coincidence experiment. Shown are the source of electrons, target gas, three electron detectors, one for the scattered electron and one for each of the ejected electrons. Two time differences, and 23, are recorded for each triple coincidence, is the difference in arrival times of ejected electron 1 and the scattered electron 23 is the difference in arrival times of ejected electron 2 and the scattered electron. Two sets of time-to-amplitude converters (TACs) and pulse height analysers/analogue-to-digital converters (PHA/ADC) convert the times to binary encoded numbers that are stored in the memory of a computer. The data can be displayed in the form of a two-dimensional histogram (see figure B 1.10.12).
The sample inlet is constituted of a heated fused silica capillary, which is maintained at approximately 200 "C and is encased in a flexible tube. The ion source, in the case of electronic ionization, is composed of electrically heated metallic filaments. Mass analyzers, separating the analytes, include time-of-flight (TOF), linear quadmpole (Q), linear quadrupole ion trap (LIT), quadmpole ion trap (QIT), Fourier transform ion cyclotron resonance (FT-ICR), etc. These detectors differ in their capacity to treat ion beams in a continuous or pulsed (TOF). Quadmpole mass analyzers stabilize and destabilize the ion paths with an oscillating electrical field. A triple quad is more recent technology and consists of three quadmpole stages. Quadmpole ion traps will sequentially eject ions that have been trapped in a ring electrode between two endcap electrodes. [Pg.289]


See other pages where Pulsed triple ionization source is mentioned: [Pg.12]    [Pg.28]    [Pg.12]    [Pg.28]    [Pg.25]    [Pg.514]    [Pg.449]    [Pg.61]    [Pg.72]    [Pg.58]    [Pg.1208]    [Pg.114]   
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