On Semiabelian π-Regular Rings

Density of Orbits of Dominant Regular Self-maps of Semiabelian Varieties

We prove a conjecture of Medvedev and Scanlon [MS14] in the case of regular morphisms of semiabelian varieties. That is, if G is a semiabelian variety defined over an algebraically closed field K of characteristic 0, and φ : G → G is a dominant regular self-map of G which is not necessarily a group homomorphism, we prove that one of the following holds: either there exists a non-constant ration...

Some Notes on Semiabelian Rings

On n-coherent rings, n-hereditary rings and n-regular rings

We observe some new characterizations of $n$-presented modules. Using the concepts of $(n,0)$-injectivity and $(n,0)$-flatness of modules, we also present some characterizations of right $n$-coherent rings, right $n$-hereditary rings, and right $n$-regular rings.

Exchange Rings Having Stable Range One

We investigate the sufficient conditions and the necessary conditions on an exchange ring R under which R has stable range one. These give nontrivial generalizations of Theorem 3 of V. P. Camillo and H.-P. Yu (1995), Theorem 4.19 of K. R. Goodearl (1979, 1991), Theorem 2 of R. E. Hartwig (1982), and Theorem 9 of H.-P. Yu (1995). 2000 Mathematics Subject Classification. Primary 16E50, 19B10. An ...

Effects of Structure and Partially Localization of the π Electron Clouds of Single-Walled Carbon Nanotubes on the Cation-π Interactions

A C102H30 graphene sheet has been rolled up to construct Single-Walled Carbon NanoTube Fragments (SWCNTFs) as parts of armchair carbon nanotubes by computational quantum chemistry methods. Non-covalent cation-π interactions of the Na+ cation on the central rings of SWCNTFs have investigated. The binding energies of the Na+-SWCNTF complexes versus ...