Tube中的模同态与模分解

本文讨论管（tube)范畴中的模同态，在不可分解模上运用[4]中特殊生成元的定义，进一步研究了管范畴中模同态的一些性质，得到了关于同态g:L→Mh,l的导出模L的直和分解及其核的构造。     

半模的张量积

本文引入了半模的张量积的泛性定义，给出了半模范畴中的有向正向系的上极限以及任意一个半模同态的上核，讨论了半模张量积的若干性质，主要结果是：证明了张量函子保持半模的右正合性和上积，并且上积保持半模的平坦性，半模范畴中的张量函子保持上极限和上核．     

具有三角分解可解李代数的表示

本文研究具有三角分解可解李代数和它的表示,探讨了具有三角分解可解李代数是广义限制李代数 的条件,对于某些 Ｓ ∈ Ｍａｐ（Ｂ,Ｆ）,在ｕ　ｓ（Ｌ,Ｓ）－模的范畴里,确定了不可约模和主不可分解模,并 对ｕ　ｓ（Ｌ,Ｓ）的块进行了描述．     

关于ann-内射模和ann-平坦模

左R—模E是ann—内射的。如果对于R的每个有限生成右零化子理想r(L)到R的R—模同态都能延拓为到E的R—模同态.同样,我们称左R—模M是ann—平坦的如果对于R的每个有限生成右零化子理想r (L),都可以得到正合列0→r(L)⊕_RM→R__R⊕M.在本文中,我们证明了R—模B是ann—平坦的当且仅当它的示性模B~·=Hom_R(B,Q/Z)是ann—内射的.     

完备随机内积模上稠定模同态的共轭算子

对定义在完备随机内积模的稠子模上的模同态引入了共轭算子的概念并讨论其基本性质,尤其证明了共轭算子的闭性.     

形式三角矩阵环上强Gorenstein平坦模

设Γ是由环R、S和双模SMR组成的形式三角矩阵环.主要讨论环Γ上的模、模同态、模正合列以及模复形.研究了强Gorenstein平坦Γ-模的若干性质及等价刻画,并证明了由模RX和SY以及左-S同态φ:M⊗RX→Y组成的Γ-模是强Gorenstein平坦模,当且仅当RX和SCokerφ均是强Gorenstein平坦模且φ为单同态.     

对偶半模与自反半模

本文在半模范畴中建立了对偶半模与自反半模的概念，并把模范畴中有关模的对偶性与自反性的结果完整地推广到半模范畴中。     

弱Hopf代数的对偶定理及Smash积的模结构

本文主要包括两方面内容:首先将Hopf代数理论中的对偶定理部分地推广到弱Hopf代数的情况;然后讨论弱Hopf代数上的Smash积的模及模同态,并部分地推广了Maschke-type定理．     

量子环面C-1上的一族Noether模

记C_-1为q=-1 的量子环面Lie代数. 本文以Laurent 多项式环C[x^±1] 为表示空间, 构造了C_-1上的一类Noether 但非Artin 的模, 并确定了它们的全部子模和商模以及它们之间的全体模同态,最后指出该模与A₁型loop代数忠实表示的关系.     

具有三角分解可解李代数的表示

本文研究具有三角分解可解李代数和它的表示,探讨了具有三角分解可解李代数是广义限制李代数的条件,对于某些s∈Map(B,F),在uφ2(L,S)-模的范畴里,确定了不可约模和主不可分解模,并对upuφ2,L,S)的块进行了描述.     

On Semiprime Goldie Modules

In this article, we investigate some properties of right core inverses. Particularly, new characterizations and expressions for right core inverses are given, using projections and {1, 3}-inverses. Also, we introduced and investigated a new generalized right core inverse which is called right pseudo core inverse. Then, we provide the relation schema of (one-sided) core inverses, (one-sided) pseudo core inverses, and EP elements.     

McCoy modules and related modules over commutative rings

Let M be a left R-module. Then M is a McCoy (resp., dual McCoy) module if for nonzero f(X)∈R[X] and m(X)∈M[X], f(X)m(X) = 0 implies there exists a nonzero r∈R (resp., m∈M) with rm(X) = 0 (resp., f(X)m = 0). We show that for R commutative every R-module is dual McCoy, but give an example of a non-McCoy module. A number of other results concerning (dual) McCoy modules as well as arithmetical, Gaussian, and Armendariz modules are given.     

Modules having Baer summands

Let R be an arbitrary ring with identity and M a right R-module with S = End_R(M). Let F be a fully invariant submodule of M and I^?1(F) denotes the set {m∈M:Im?F} for any subset I of S. The module M is called F-Baer if I^?1(F) is a direct summand of M for every left ideal I of S. This work is devoted to the investigation of properties of F-Baer modules. We use F-Baer modules to decompose a module into two parts consists of a Baer module and a module determined by fully invariant submodule F, namely, for a module M, we show that M is F-Baer if and only if M = F⊕N where N is a Baer module. By using F-Baer modules, we obtain some new results for Baer rings.     

Monomial Modules and Endo-Monomial Modules

We determine the multiplicity algebras and multiplicity modules of a p-monomial module. For a general p-group P, we find a sufficient and necessary condition for an endo-monomial P-module to be an endo-permutation P-module, and prove that a capped indecomposable endo-monomial P-module is of p ^′-rank. At last, we give an alternative definition of the generalized Dade P-group.     

A generalization of silting modules and Tor-tilting modules

We introduce the concept of weak silting modules, which is a generalization of both silting modules and Tor-tilting modules. It is shown that W is a weak silting module if and only if its character module W⁺ is cosilting. Some properties of weak silting modules are given.     

Weakly dual automorphism invariant and superfluous cotightness

Abstract

The aim of the present paper is to introduce and study the dual concepts of weakly automorphism invariant modules and essential tightness. These notions are non-trivial generalizations of both weakly projectivity, dual automorphism invariant property and cotightness. We obtain certain relations between weakly projective modules, weakly dual automorphism invariant modules and superfluous cotight modules. It is proved that: (1) for right perfect rings, every module is a direct summand of a weakly dual automorphism invariant module and (2) weakly dual automorphism invariant modules are precisely superfluous cotight modules.     

Lifting Modules with Indecomposable Decompositions

A module M is called a “lifting module” if, any submodule A of M contains a direct summand B of M such that A/B is small in M/B. This is a generalization of projective modules over perfect rings as well as the dual of extending modules. It is well known that an extending module with ascending chain condition (a.c.c.) on the annihilators of its elements is a direct sum of indecomposable modules. If and when a lifting module has such a decomposition is not known in general. In this article, among other results, we prove that a lifting module M is a direct sum of indecomposable modules if (i) rad(M ^(I)) is small in M ^(I) for every index set I, or, (ii) M has a.c.c. on the annihilators of (certain) elements, and rad(M) is small in M.