Hyperbolic quadrupole systems

Figure 2.177 Ion transmission of round and hyperbolic quadrupole systems (resolving power ag. ion transmission), first documented investigation by Brubaker (1968) (two curves left round rods two curves right hyperbolic rods).

The hyperbolic quadrupole is shown between the reaction cell and the detector. The sample introduction system and ICP torch ate on the left of the diagram. ( 2013 Agilent Technologies. www.agilent.com/chem. All rights reserved. Used with pennission.)... 

The most common mass spectrometer used in GC-MS systems is the quadrupole mass spectrometer, either as a single quadrupole or as a triple quadrupole, which can also provide MS-MS spectra. A diagram of a quadrupole mass spectrometer is shown in Fig. 4. The operation of the quadrupole mass spectrometer is quite different from that of the sector instrument. The instrument consists of four rods which must be precisely straight and parallel and so arranged that the beam of ions is directed axially between them. Theoretically, the rods should have a hyperbolic cross section, but in practice, less ex-... 

Proton Transfer Reaction Linear Ion Trap Mass Spectrometer (PTR-LIT-MS) To expand the capacity of PTR-MS to differentiate isobars at ppt level, PTR-LIT-MS has been developed [18], which is similar to the PTR-IT-MS but uses a linear quadrupole IT instead of a hyperbolic IT. In the LIT system, ions are... 

The EM quadrupole trap (Paul trap) is formed by a ring electrode with a hyperbolic surface and a ring radius of ro as one pole, and two hyperbolic caps as the second pole (Fig. 14.23). The whole system has cylindrical sym-... 

Developed in the early 1980s, quadrupole-based systems represent approximately 85% of all ICP mass spectrometers used today. This design was the first to be commercialized, and as a result, today s quadrupole ICP-MS technology is considered a very mature, routine trace element technique. A quadrupole consists of four cylindrical or hyperbolic metallic rods of the same length and diameter. They are typically made of stainless steel or molybdenum and sometimes coated with a ceramic coating... 

The electric quadrupole field is formed by applying a voltage U between a ring electrode with hyperbolic surface as one pole and two hyperbolic caps as the other pole (Fig.13.13). The whole system has axial symmetry with respect to the z axis. In a geometrical arrangement where the inner ring radius rg is related to the cap separation 2Zg by rg = /2 Zg the electric potential 0 for points within the trap can be written as [13.20]... 

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