Lifting zero-dimensional schemes and divided powers

We study divided power structures on finitely generated k-algebras, where k is a field of positive characteristic p. As an application we show examples of zero-dimensional Gorenstein k-schemes that do not lift to a fixed noetherian local ring of non-equal characteristic. We also show that Frobenius neighbourhoods of a singular point of a general hypersurface of large dimension have no liftings to mildly ramified rings of non-equal characteristic.