循环矩阵环的局部化

本文的主要结果如下：(1)环R关于其乘法封闭子集S满足左Ore条件当且仅当R[σ1,σ2,…，σt]关于其相应乘法封闭子集S[σ1,σ2,…，σt]满足左Ore条件．(2)若R关于其乘法封闭子集S满足左Ore条件，S^-1 R是R关于S的左分式环，其自然同态为φ：R→S^-1R，则存在环同态φ：R[σ1,σ2,…,σt]→S[σ1,σ2,…,σt]^-1 R[σ1,σ2,…σt]使得(S-1R)[φ（σ1),φ-(σ2),…φ（σt)]≌S[σl，σ2，…，σt]^-1R[σ1,σ2,…σt]。     

局部单位元半群分次环

设S为有限局部单位元半群,R为S—分次环.首先定义了S—分次环R在半群S上的冲积R#S*,证明了模范畴R#S*-M od与分次模范畴(S,R)-g r之间的等价性,并进一步研究了局部单位元半群分次环的分次Jacobson根及其相关的自反根的关系,得到重要关系式J(R#S*)=JS(R)#S*及Jref(R)=(J(R#S*))↓=JS(R).     

分次环的分次Jacobson根

本文通过引入弱拟正则元的概念，对一般Ｍｏｎｏｉｄ分次环Ａ（未必有１）给出以内部元素刻划的分次Ｊａｃｏｂｓｏｎ根ＪＧ（Ａ）．证明当Ａ有１时，ＪＧ（Ａ）与通常定义的Ｊｇ（Ａ）相等．对ＪＧ（Ａ）性质的讨论，推广了最近的许多结果．作为应用，我们给出了Ａｒｔｉｎ分次环的全部基本结构定理．     

分次FS—环

本文引进群分次环上分次模的分次ＦＳ－模的概念,利用分次极大分次左理想给出分次ＦＳ－环的几个刻画,得到了环Ｒ和群环ＲＧ,分次环Ｒ和分次环的群环Ｒ「Ｇ」间的几个等价条件。     

群分次环的分次Levitzki根

建立了分次环的分次Levitzki根,并给出了分次Levitzki半单环的结构定理及相关结果.     

分次环的分次Excellent扩张

本文引进了分次环的分次Excellent扩张概念,设S=⊕_(g∈G)S_g是R=⊕_(g∈G)R_g的分次Excellent扩张,证明了S是分次右V-环当且仅当R是分次右V-环,S是分次PS-环当且仅当R是分次PS-环,S是分次Von Neumann正则环当且仅当R是分次Von Neumann正则环。     

分次Armendariz环与P.P.环

引进分次Armendariz环的概念,讨论了分次环R= n∈2Rn及由它导出的非分次环R,R0,及R[x]之间关于Armendariz环性质的关系,并推广了[8]的结论,得到在R= n∈ZRn是Z-型正分次环的前提下,若R是分次Armendariz,分次正规环,则R是P．P环（Bear环）当且仅当R是分次P．P．环（分环Baer环）。     

Graded Endomorphism Rings and Equivalences

Abstract

Let R be a G-graded ring,M a G-graded Σ-quasiprojective R- module,and E = END _R (M) its graded ring of endomorphisms. For any subgroup H of G,we prove that certain full subcategories of G/H-graded R-modules associated with M are equivalent to a quotient category of G/H-graded E-modules determined by the idempotent G-graded ideal of E consisting of endomorphisms which factor through a finitely generated submodule of M. Properties and applications of these equivalences are also examined.     

The Ideal Intersection Property for Groupoid Graded Rings

We show that, if a groupoid graded ring has a grading satisfying a certain nondegeneracy property, then the commutant of the center of the principal component of the ring has the ideal intersection property, that is it intersects nontrivially every nonzero ideal of the ring. Furthermore, we show that for skew groupoid algebras with commutative principal component, the principal component is maximal commutative if and only if it has the ideal intersection property.     

On Minimal Graded One-sided Ideals and Graded Primitive Rings

In this paper, sturcture theorems are given for graded primitive rings with minimal graded one-sided ideals and arbitrary minimal graded one-sided ideals of general group-graded rings respectively.     

A Note on the Graded K-Theory of Certain Graded Rings

Following ideas of Quillen we prove that the graded K-theory of a ? ⁿ -graded ring with support contained in a pointed cone is entirely determined by the K-theory of the subring of degree 0 elements.     

Good Gradings of Generalized Incidence Rings

This inquiry is based on both the construction of generalized incidence rings due to Gene Abrams and the construction of good group gradings of incidence algebras due to Molli Jones. We provide conditions for a generalized incidence ring to be graded isomorphic to a subring of an incidence ring over a preorder. We also extend Jones's construction to good group gradings for incidence algebras over preorders with crosscuts of length one or two.     

On Chow Groups of G-Graded Rings

Abstract

Let A be a Noetherian ring graded by a finitely generated Abelian group G. It is shown that a Chow group A _?(A) of A is determined by cycles and a rational equivalence with respect to certain G-graded ideals of A. In particular, A _?(A) is isomorphic to the equivariant Chow group of A if G is torsion free.     

Localization and Catenarity in Strongly Graded Rings

The objective of this article is the study of localization and catenarity in strongly G-graded rings with Noetherian base ring, where G is a finitely generated, nilpotent and torsionfree group. We generalize some results of Guédénon (2000 Guédénon , T. ( 2000 ). Anneaux munis d'une action de groupe superrésoluble . Algebras Groups and Geometries 17 : 17 – 48 . [CSA]  [Google Scholar]). It follows from Corollary 2.6 that if G is free Abelian of finite rank and A is a commutative strongly G-graded ring with base ring a Noetherian regular integral domain, then A is a Noetherian regular integral domain.     

Introducing Crystalline Graded Algebras

We develop a generalization of the traditional crossed products and we derive general structural properties. Localization at a particular Ore set is investigated and as a consequence the relation to crossed products is examined. Finally, examples are given. Presented by Alain Verschoren.