设R是环,定义了(d,n)-余挠模与(d,n)-平坦模,并研究了这两类模的性质.证明了(fdn,ld,n)是完全且遗传的余挠理论,其中fd.n(ld,n)表示(d,n)-平坦右R-模类((d,n)-余挠右-模类).给出了这两类模在环的优越扩张下的等价刻画.%Let R be any rings,(d,n)-cotorsion modules and (d,n)-flat modules are defined,and their properties are investigated.It is proved that (fd,n,ld,n) is complete hereditary cotorsion theory,where fd,n (ld,n) denotes the class of all (d,n)-flat ((d,n)-cotorsion) right R-modules.The equivalent descriptions of these modules under excellent extensions of rings are given.
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