Likewise, nitrogen oxides and sulfur dioxide react with other chemicals in the atmosphere under the influence of intense sunshine to form ozone, which is a main ingredient of photochemical smog. (religion-online.org)
The findings are timely because the Environmental Protection Agency is developing stricter regulations for ground - level ozone, a primary component in photochemical smog. (sciencedaily.com)
The artist has taken silk film through photochemical processes, coating these delicate surfaces with cyanotype solution. (fluxfactory.org)