| 摘要 |
PURPOSE:To detect the concentration of aerosol simply with an instantaneous expansion of air in a container by connecting the outside of a porous plate to a high pressure/ low pressure tank with a changeover valve after it is srranged on both sides of a flexible film which seals up an opening of a container having a hygroscopic material applied thereon. CONSTITUTION:Porous plates 13 and 14 are arranged both on the inside and outside of a flexible film 12 sealing up an opening of a container 1 and additionally, the outside thereof is sealed up with a lid body 15. The flexible flexible film 12 tightly contacts the porous plate 13 under an atmospheric pressure of a high pressure tank 20. But when the outside of the flexible film 12 is connected to a low pressure tank 21 by switching a valve 17, the flexible film 12 tightly contacts the porous plate 14 instantaneously and the closed air with the humidity of 100% is expanded adiabatically by moisture contained in a hygroscopic material 2. Beam of a projector 9 scattered by a mist generated in the container is detected with a photodetector 10 to find the concentration of an aerosol. As the flexible film 12 is tight on the porous plate, the variation in the capacity is constant. Thus, the concentration of aerosol can be found instantaneously with a simple contruction thereby assuring an accurate observation with a high duplicability. |
