  In this paper, we study homological properties of twisted tensor products of
connected graded algebras. We focus on the Ext-algebras of twisted tensor
products with a certain form of twisting maps firstly. We show those
Ext-algebras are also twisted tensor products, and depict the twisting maps for
such Ext-algebras in-depth. With those preparations, we describe Nakayama
automorphisms of twisted tensor products of noetherian Artin-Schelter regular
algebras.
