| 摘要 |
PURPOSE:To measure easily the number of fine grains by using a water vapor for generating no nasty small, and causing a nucleus condensation by using the fine grain of an aerosol as a nucleus. CONSTITUTION:When air in a mixing chamber 26 is absorbed through an exhaust duct 31 by operating a pump 34, clean air is given to a high temperature saturated vapor chamber 23 through a valve 20 and a filter 22. In the vapor chamber 23, water is heated by a heater 24, and the clean air is changed to a high temperature saturated water vapor and transmitted to the mixing chamber 26. An aerosol containing grains to be measured is given to the mixing chamber 26 through a duct 27, and in the mixing chamber 26, the aerosol of a room temperature and the clean high temperature saturated vapor are mixed, and a condensed nucleus which grows by using the fine grain of the aerosol as a nucleus is ejected out to a measuring chamber 7 from the center jet port of a nozzle 28. When this condenced nucleus passes through the focus of a laser beam from a light source chamber 1, the laser beam is scattered, and this scattered light is condensed by condensing lenses 9, 10, transmitted to a photoelectric converter 11, converted to an electric signal corresponding to the number of fine grains, and counted. |
