| 摘要 |
PURPOSE:To measure the concentration of dust of massive sample for a short time even when the number of particles per unit volume by giving a temperature gradient to a sample earozol in an axial symmetry. CONSTITUTION:A proper heating body H is mounted in the perimeter of a part or a whole of a nozzle N for introducing a sample earozol S to give a temperature gradient to the sample earozol S in an axial symmetry whereby floating particles are condensated axially with an aid of thermophresis. An irradiation beam is applied to a part Sr shown by a diameter WA biased on the axis of the sample earozol S to measure scattered light thereby enabling the measurement of the number of dust particles. Therefore, the quantity of the beam can be reduced to a level by far less than that when beam is irradiated on the flow of the sample as shown by the diameter WA and particles about 0.1mum in the size can be detected accurately eliminating obstruction by scattered beam due to gas molecule. |
