| 摘要 |
1,222,600. Gas analysis. GENERAL ELECTRIC CO. Dec.23, 1968 [Dec. 26, 1967], No.61074/68. Heading G1B. A method of determining a chemically reactive gas in a carrier gas e.g. ammonia in air comprises the steps of introducing the gases into a chamber 10 through an inlet 11 and in so doing exposing it to radiation from a radioactive material 15 by an alpha or beta emitter, treating the ionized gases with a reagent vapour, e.g. from a pool of 20% hydrochloric acid to produce condensation nuclei of ammonium chloride and containing the nuclei in a condensation nuclei detector 21 connected to the chamber 10 by way of an outlet 12. The radioactive material which may be a polonium alpha source or a beta source such as Krypton 85 ionses the ammonia entering the chamber 10 and enhances the sensitivity of the process since the detector 21 is more sensitive to ionized particles than to uncharged particles of ammonium chloride. A pump 20 is used to draw the gases through the chamber 10. |
