The article investigates show theoretically that superconductor can violate the 2nd law. Therefore, the classical London theory is extended in order to predict the time-dependent behavior of superconductors. Different to prior models it contains a 2-fold time derivative of the magnetic field B and includes the self induction of the superconducting probe. It predicts an inverted (gain)-hysteresis in the M-H diagram for non-stationary cycles which violates the 2nd law. The gain estimated is measurable. If this effects can be really observed also for high Tc - materials this effect can be used to build 100% heat-electricity converters .weiterlesen