in this paper, we introduce a class of rings which is a generalization of reversible rings. let r be a ring with identity. a ring r is called central reversible if for any a,b ∈ r, ab=0 implies ba belongs to the center of r. since every reversible ring is central reversible, we study sufficient conditions for central reversible rings to be reversible. we prove that some results of reversible ri...

We extend the analogy between extended Robba rings of [Formula: see text]-adic Hodge theory and one-dimensional affinoid algebras rigid analytic geometry, proving some fundamental properties that are well known in latter case. In particular, we show these regular excellent. The interest as they used to build Fargues–Fontaine curve.

An environmentally friendly, facile and solvent-free synthetic route for aluminum sulfate octadecahydrate (Al2(SO4)3.18H2O) catalyzed one-pot multi-component synthesis of 12-aryltetrahydrobenzo[α]xanthene-11-ones, 1,8-dioxo-octahydroxanthenes and 14-aryl-14Hdibenzo[α,j]xanthenes has been developed. The readily, easy to handle, non-toxic, environmental friendly and low-cost catalyst, easily sepa...

We prove that a C 2+α-smooth orientation-preserving circle diffeomorphism with rotation number in Diophantine class D δ , 0 < δ < α ≤ 1, is C 1+α−δ-smoothly conjugate to a rigid rotation. We also derive the most precise version of Denjoy's inequality for such diffeomorphisms.

in this paper we focus on a special class of commutative local‎ ‎rings called spap-rings and study the relationship between this‎ ‎class and other classes of rings‎. ‎we characterize the structure of‎ ‎modules and especially‎, ‎the prime submodules of free modules over‎ ‎an spap-ring and derive some basic properties‎. ‎then we answer the‎ ‎question of lam and reyes about strongly oka ideals fam...

A novel Cu(II)-catalyzed cyclization of α-diazo-β-oxoamides with amines has been developed, constituting a straightforward method to construct pyrrol-3(2H)-one rings. The intramolecular hydrogen bonding effect in α-diazo-β-oxoamides plays an essential role in this reaction. A plausible reaction mechanism involving divergent generation and subsequent [2 + 3] cyclization of ketene and α-diazoimin...