Spatial temporal postulate

Within the macroscopic postulates of the theory detonations in condensed phases are generally considered to be quantitatively well defined, while deflagrations are less determinable because of their greater dependence on temporal and spatial factors. For example, in propellant deflagrations, where the reaction rates are strongly dependent on the diffusion of reactants to an interface, propagation velocities may be down to centimeters per second or less, or as high as meters per second. 

Spatio and Spatio-Temporal Patterns. An exotic form of diffusional encounter should be mentioned, which arises from sets of reaction-diffusions equations (48). In 1952, the mathematician Alan Turing postulated the existence of two-dimensional and three-dimensional spatio and spatio-temporal patterns for certain classes of reactive systems (49). The physical realization of these mathematical solutions has been observed in a variety of systems (50). It suffices to say that since these patterns have been observed in both simple chemical systems and complex biological systems, their possibility in homogeneous catalysis should certainly not be ruled out. In this regard, static spectroscopic cells may be particularly prone to such spatial variation because of the lack of mixing. 

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