幂级数π-Armendariz环

引入幂级数π-Armendariz环的概念,研究了幂级数π-Armendariz环的扩张,证明了如果环R是具有幂零有界指数的NI环,且为α-容许环,则R[x;α]是幂级数π-Armendariz环.同时讨论了幂级数环的幂零p.p.性和弱zip性.

(α,δ)-弱刚性环上的Ore扩张（英文）

本文研究(α,δ)-弱刚性环上的Ore扩张环R[x;α,δ]的弱对称性、弱zip性、幂零p.p.性和幂零Baer性.利用对多项式的逐项分析的方法,证明了如果R是(α,δ)-弱刚性环和半交换环,则Ore扩张环R[x;α,δ]是弱对称的(弱zip的,幂零p.p.的,幂零Baer的)当且仅当R是弱对称的(弱zip的,幂零p.p.的,幂零Baer的).这些结果统一和扩展了前面已有的相关结论.

Existence of Multiple Positive Periodic Solutions for Second Order Differential Equations

Let α be a nonzero endomorphism of a ring R, n be a positive integer and T_n（R, α） be the skew triangular matrix ring. We show that some properties related to nilpotent elements of R are inherited by T_n（R, α）. Meanwhile, we determine the strongly prime radical, generalized prime radical and Behrens radical of the ring R[x; α]/（x^n）, where R[x; α] is the skew polynomial ring.