SOUND-ABSORPTIVE STRUCTURE

摘要

PROBLEM TO BE SOLVED: To not only reduce noise but also reduce pollutants like nitrogen oxides or sulfur oxides in the air discharged from the exhausted gas of cars. SOLUTION: A sound-absorption material 3 is charged in a hollow body 1 provided with an external layer 4 containing titanium dioxide at the surface and a number of openings 11 to irradiate ultraviolet rays on the titanium dioxide and activate it. In this way, noise of running cars is led into the hollow body 1 through the openings and absorbed by the sound-absorption material 3. The air near the ground level in which much pollutants like nitrogen oxides or sulfur oxides are contained, are stirred up by the wind pressure caused by running cars and led to the surface of the hollow body 1. The nitrogen oxides and sulfur oxides are guided to contact titanium dioxide of the external layer 4 and the nitrogen oxides and sulfur oxides are oxidized to nitric acid or sulfuric acid by the strong oxidizing force of the activated titanium dioxide and effectively removed.