Topic: outdoor displays led

We often see a gray sky in the morning, but it is actually covered by something called smog. It is estimated that many people still do not know what smog is. Its main components are formed by a mixture of sulfur dioxide, nitrogen oxides and inhalable particulate matter. The first two are gaseous pollutants. They combine with fog to make the sky instantly change. It was gray. In fact, fog is a non-toxic and harmless natural phenomenon, and the formation of haze is mainly the result of the joint a...