Gradient, of parameter

Here, v is the volume occupied by one particle (molecule) of the matter, and dcLi/dx. is the gradient of parameter a along space coordinate x. 

By contrast, there is no doubt or any contradictions in literature concerning the importance of macro-kinetic factors (heat- and mass-transfer processes) in the reactions discussed in this section. It is generally realized that these processes proceed in spatially distributed systems and generate sharp gradients of parameters (temperature, pressure, density, concentrations, etc). It could be noted here a distinct similarity of alkane oxidation over Pt-group metals at short contact times and well studied and practically implemented ammonia oxidation and cyanic acid synthesis reactions, in which transfer processes play a dominant role (see Satterfield, 1970). 

Wave Front Breaks and Emergence of Spiral Waves at Local Gradients of Parameters... 

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