A Problem of Outgassing and Contamination with Multiplying Boundary Conditions

A mathematical model for the description of processes of outgassing and contamination is studied under the assumption that the boundary surface between the region where the contaminant particles are produced and the cavity, where they migrate, is multiplying. The theory of semigroups is used to show that a unique positive strict solution exists. Suitable bounds for the total number of contaminant particles are derived.