Regularization of Mickelsson generators for nonexceptional quantum groups

Let g′ ⊂ g be a pair of Lie algebras of either symplectic or orthogonal infinitesimal endomorphisms of the complex vector spaces C N−2 ⊂ C N and U q (g′) ⊂ U q (g) be a pair of quantum groups with a triangular decomposition U q (g) = U q (g-)U q (g+)U q (h). Let Z q (g, g′) be the corresponding step algebra. We assume that its generators are rational trigonometric functions h ∗ → U q (g±). We describe their regularization such that the resulting generators do not vanish for any choice of the weight.