Singular perturbation theory
نویسنده
چکیده
When we apply the steady-state approximation (SSA) in chemical kinetics, we typically argue that some of the intermediates are highly reactive, so that they are removed as fast as they are made. We then set the corresponding rates of change to zero. What we are saying is not that these rates are identically zero, of course, but that they are much smaller than the other rates of reaction. The steady-state approximation is often surprisingly accurate, but the classical arguments lack rigor and don’t lead to any satisfying mathematical generalization which can be used to improve on the approximation. There are two mathematical theories which build on the SSA and provide the required generalization:
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