Single site reactorcatalyst continuity in a dispersed phase reaction in terms of initial activation and subsequent deactivation may be improved by treating the support with a metal salt. In a first aspect, the MEMS device comprises a MEMS resonator, a limiter coupled to the MEMS resonator, and a regulator coupled to the limiter. A primary plunger, which is movable in the syringe body and in the needle, comprises a limit stop that can cooperate with the syringe body.