| 摘要 |
PCT No. PCT/GB89/00622 Sec. 371 Date Dec. 3, 1990 Sec. 102(e) Date Dec. 3, 1990 PCT Filed Jun. 5, 1989 PCT Pub. No. WO89/12313 PCT Pub. Date Dec. 14, 1989.There is disclosed a double-focusing mass spectrometer in which ions are generated from a sample in a microwave-induced or inductively-coupled plasma (3). Ions are sampled from the plasma (3) through an aperture in a sampling cone (19) and pass through a skimmer cone (28) and several electrostatic lenses (30,33) to the entrance slit of the mass analyzer. The sampling cone (19) and skimmer cone (28) are maintained by a power supply (40) at a potential approximately equal to the accelerating potential required by the mass analyzer. It is found that the plasma potential may be maintained at such a value that a substantial proportion of the ions generated in the plasma (3) have energies lying within the energy passband of the mass analyzer, so that a high sensitivity, high resolution mass spectrometer especially suitable for the elemental analysis of solid or liquid samples is provided. Such a spectrometer is capable of resolving many of the spectral interferences which restrict the usefulness of conventional quadrupole based plasma mass spectrometers.
|
