Right C-Qrpp Semigroups

In this thesis, we investigate a class of weak rpp semigroups, named rightC-qrpp semigroups. Right C-qrpp semigroups are analogue of right C-rpp semi-groups in the range of weak rpp semigroups. This thesis is divided into threechapter.In Chapter 1, we introduce the concept of right C-qrpp semigroups and estab-lish some characterizations of right C-qrpp semigroups. In particular,it is provedthat a strongly qrpp semigroup S is a right C-qrpp semigroup if and only if S is asemilattice of direct products of left-R cancellative monoid with right zero band.Chapter 2 is devoted to the construction problem of right C-qrpp semigroups.It is proved that a semigroup is a right C-qrpp semigroup if and only if it isisomorphic to a rightΔ-product of a C-wrpp semigroup and a right regular band.In Chapter 3, we obtain many characterizations of right C-qrpp semigroups.And then, we introduce the concept of dual semi-spined products. This showsanother method to construct right C-qrpp semigroups. Finally, it is proved thata semigroup is a right C-qrpp semigroup if and only if it is isomorphic to somedual semi-spined product of a C-wrpp semigroup and a right regular band.