in the past decade, magnetic nanomaterials have attracted much attention due to their physical properties and technological applications. in this work, α-fe2o3 nanoparticles were first synthesized via a simple co-precipitation method using iron chloride hexahydrate (fecl3.6h2o) as precursor and ammonia solution as precipitator. the samples were then characterized by high resolution transmission...

we show that every semi-artinian module which is contained in a direct sum of finitely presented modules in $si[m]$, is weakly co-semisimple if and only if it is regular in $si[m]$. as a consequence, we observe that every semi-artinian ring is regular in the sense of von neumann if and only if its simple modules are $fp$-injective.