| 摘要 |
PURPOSE:To enable the matching of impedances between loads at a high frequency power source and a plasma torch, by sequentially changing at least one of a solvent, the type of gas and the flow rate of gas of a sample aerosol to be introduced into a plasma torch. CONSTITUTION:Power to be outputted from a high frequency power source 6 is supplied to an induction coil 4 through a matching box 8 with a coaxial cable 10. In this case, the capacities of capacitors 8a and 8b of a box 8 left fixed at, for example, C0. On the other hand, argon gas is supplied from a gas controller 12 and introduced into a plasma torch 2 by a corona discharge to light plasma. With the plasma lighting, reflectance coefficient moves to the point (b) from the point (a). So, water-based aerosol is introduced into the torch 2, the reflectance coefficient is moved to the point (c) from the point (a). Then, as the type of gas to be introduced is charged while introducing an organic solvent-based aerosol into the torch 2, the matching characteristic of the impedance changes from a curve S3 to S4. With this, the reflectance coefficient moves from the point (c) to the maximum point (e).
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