| 摘要 |
1,274,641. Burners for spectroscopy. G. F. KIRKBRIGHT. 20 May, 1969 [23 May, 1968], No. 24697/68. Heading F4T. In a burner assembly for use in flame emission and absorption spectroscopy and comprising a burner head having one or more apertures 2 at which a flame can be supported, means for supplying gas to be burnt to the aperture or apertures, a circumferentially-extending opening which surrounds the burner head, and conduit means 3 for supplying inert gas to the opening, the conduit means 3 is so arranged that for a range of velocities of the inert gas leaving the opening, a lower part of the flame 10 adjacent to the burner head is shielded from the atmosphere by the inert gas so that the secondary zone 9 of the flame is spaced apart from the burner head. As shown, the conduit means comprises alternate layers of plain, 5, and corrugated, 6, strips, the longitudinal axes of the corrugations lying parallel to the direction of gas flow through the burner assembly and the strips being located between inner and outer walls of the conduit means. Alternatively, the conduit means may comprise a plurality of hypodermic needles. To produce a substantially flat flame, there may be a row of apertures (Fig. 17, not shown) or a single elongated aperture (Fig. 20, not shown), in the burner head, and in these cases the conduit means may be oval or rectangular in cross-section. Gas flowing to the burner head may be kept cool by the provision of a metal mass of high thermal conductivity in thermal contact with the head (Fig. 14, not shown), or by air or water cooling in the burner assembly. Inert gases used are nitrogen and argon, while suitable gases for burning are hydrocarbon/air and hydrocarbon/nitrous oxide mixtures respectively. |
