  We discuss stationary concentrations of reactants in an A + B -> 0 reaction
under subdiffusion and show that they are described by stationary
reaction-diffusion equations with a nonlinear diffusion term. We consider
stationary profiles of reactants' concentrations and of reaction zones in a
flat subdiffusive medium fed by reactants of both types on its both sides (a
subdiffusive gel reactor). The behavior of the concentrations and of the
reaction intensity in subdiffusion differs strikingly from those in simple
diffusion. The most important differences correspond to the existence of
accumulation and depletion zones close to the boundaries and to non-monotonous
behavior of the reaction intensity with respect to the strength of the minor
source. The implications of these results for other situations are also
discussed.
