Twists and quantizations of Cartan type S Lie algebras

We construct explicit Drinfel'd twists for the generalized Cartan type S Lie algebras and obtain the corresponding quantizations. By modular reduction and base changes, we obtain certain quantizations of the restricted universal enveloping algebra u(S(n;1_)) in characteristic p. They are new Hopf algebras of truncated p-polynomial noncommutative and noncocommutative deformation of dimension p1+(n-1)(pn-1), which contain the well-known Radford algebra (Radford (1977) [23]) as a Hopf subalgebra. As a by-product, we also get some Jordanian quantizations for sln.