A theoretical explanation for the experimentally observed enhanced surface recombination of the ions in a thermally ionized magnetoplasma in a Q-device is proposed. It is based on a collisionless treatment which yields a non-Maxwellian velocity distribution for the plasma particles (section 2). In section 3 the influence of rate collisions on the velocity distribution , particularly in double-ended operation, (D.E., bothendplates hot) is discussed and it is shown that even in the case of a partially thermalized plasma with a thermalization rat e of about 50% the surface recombination causes still a J0 ∼ n dependence instead of a J0 ∼ n2 dependence as found in the case of a fully thermalized plasma.