Reaction pathways numerical experiments

Concerning the reaction pathway, two routes have been proposed the sequence of total oxidation of methane, followed by reforming of the unconverted methane with CO2 and H2O (designated as indirect scheme), and the direct partial oxidation of methane to synthesis gas without the experience of CO2 and H2O as reaction intermediates. The results obtained by Schmidt and his co-workers [4, 5] indicate that the direct reaction scheme may be followed in a monolith reactor when an extremely short contact time is employed at temperatures in the neighborhood of 1000°C. However, the majority of previous studies over numerous types of catalysts show that the partial oxidation of methane follows the indirect reaction scheme, which is supported by the observation that a sharp temperature spike occurs near the entrance of the catalyst bed, and that essentially zero CO and H2 selectivity is obtained at low methane conversions (<25%) where oxygen is not fully consumed [2, 3]. A major problem encountered... 

During the past 50 years, numerous experiments have been performed in attempts to unravel the complex pathways whereby steroid hormones, that is the corticosteroids, androgens and oestrogens, are formed in mammalian and other tissues. A very large number of books and reviews have already been written on the subject and this present chapter will seek to (a) summarize the pathways concerned and how the evidence for these was obtained and (b) provide an update of advances over the past decade, particularly with regard to the properties of the steroid transforming enzymes involved and the mechanism of the reactions catalysed by such enzymes. 

The drastic changes that are implicit in this discussion are compatible with the rather harsh reaction conditions employed in this experiment. In fact, instead of limiting alternatives, strongly acidic media in highly polar solvents (acetic acid) facilitate the numerous pathways open to thermal induction and... 

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