smoke stone
1.Black clouds of smoke and the noise of gunfire enveloped the residential area along the main road out of Douala towards the capital, Yaoundé, where police later tear-gassed stone-throwing youths who had set up burning barricades.
2.This paper has summarized the researches on the application of such mineral materials as activated carbon, zeolite, montmorillonite, sepiolite, medical stone, palygorskite, aluminum oxide, sodium hydrate, alumen and nanomaterials as cigarette tip additives to the removal of harmful components in cigarette smoke in the last decades.
