Coke (fuel) Coke (fuel) Coke is a fuel with a high carbon content and few impurities, made by heating coal in the absence of air. It is the solid carbonaceous material derived from destructive distillation of low-ash and low-sulfur bituminous coal. Cokes made from coal are grey, hard, and porous. While coke can be formed naturally, the commonly used form is synthetic. The form known as petroleum coke, or pet coke, is derived from oil refinery coker units or other cracking processes. Coke is used in preparation of producer gas which is a mixture of carbon monoxide (CO) and nitrogen (N). Producer
Evolutionary history of plants established; as it is still difficult to predict whether a plant with more secondary metabolites increases its survival or reproductive success compared to other plants in its vicinity. Secondary metabolite production seems to have arisen quite early during evolution. In plants, they seem to have spread out using mechanisms including gene duplications or the evolution of novel genes. Furthermore, research has shown that diversity in some of these compounds may be positively selected for. Although the role of novel gene evolution in the evolution of secondary metabolism is clear, there are several examples where new metabolites have been formed by