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31.
The Cayley-Bacharach Property (CBP), which has been classically stated as a property of a finite set of points in an affine or projective space, is extended to arbitrary 0-dimensional affine algebras over arbitrary base fields. We present characterizations and explicit algorithms for checking the CBP directly, via the canonical module, and in combination with the property of being a locally Gorenstein ring. Moreover, we characterize strict Gorenstein rings by the CBP and the symmetry of their affine Hilbert function, as well as by the strict CBP and the last difference of their affine Hilbert function. 相似文献
32.
The main products of graft copolymerization of acrylonitrile (AN) onto casein in concentrated aqueous solution of sodium thiocyanate in homogeneous phase were characterized as a graft copolymer (AN-g-casein) by Fourier transform infrared. The effects of the monomer concentration, initiator concentration, reaction temperature and reaction time on copolymerization were investigated. The result of WAXD showed that the major part of casein in graft copolymer is amorphous. The SDSC determination showed that the lateral order of PAN, the side chain of copolymer, decreases and the lateral order distribution becomes wider with the increase of the casein component in copolymer. It revealed that the two systems of AN-g-casein copolymer are incompatible by an investigation of DMTA, SEM. The two systems of AN-g-casein exist in separating phases, but tie up each other. So the phenomena of characteristic boundary relaxation occur.Direct spinning of graft copolymer in concentrated aqueous solution of sodium thiocyanate in homogeneous phase was successfully carried out. The skin-core layer structure of AN-g-casein fiber cross-section was observed by scanning electron microscope (SEM). In the core layer, the dimension of phase domain of casein is about from 20 to 60 nm. When the fiber was drawn into broken, microfibrillation occurs, the fiber skin layer is compact, and its broken section is flat. Many long and thin casein strips are formed in the surface of the fiber, respective crystalline grade of two components is scarcely effected by the change of the content of casein. AN-g-casein fibers have good hygroscopicity and dyeability, and more, they can be dyed by acidic dyestuff and cationic dyestuff. AN-g-casein fiber still has good mechanical properties, so AN-g-casein fiber is a new type modified “silk-like” fiber for wide application. 相似文献
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34.
证明了非紧模糊数空间E^~在下方图度量下关于模糊数的序是可逼近的。本文给出的证明方法是构造性的,从而说明了模糊数值积分如M-积分和G-积分等是可计算的。最后给出了E^~中关于下方图度量的一些分析性质。 相似文献
35.
36.
本文系统地研究了α和βi(i=1,2 ,3) - K5Si Al(OH2 ) W11O3 9· n H2 O的氧化还原性质 ,通过导数脉冲伏安、常规脉冲伏安确定了其氧化还原机理 ,并比较了其氧化还原性质的强弱。 相似文献
37.
A 2‐fold parallel interpenetrated polymer, ZnCo(OH)(pheno)(p‐BDC)1.5·H2O ( 1 ) (pheno = phenanthrene‐9,10‐dione; p‐BDC = 1,4‐benzenedicarboxylate) has been prepared by hydrothermal synthesis and structurally characterized by IR, elemental analysis, ICP and single crystal X‐ray diffraction. Complex 1 crystallizes in the orthorhombic space group Pbca and affords a three‐dimensional (3D) six‐connected α‐Po network. The magnetic behavior for 1 was studied in the temperature range of 1.8‐300 K. 相似文献
38.
Jerzy A. Filar 《Mathematical Programming》1984,30(3):313-325
We consider a two-person, general-sum, rational-data, undiscounted stochastic game in which one player (player II) controls
the transition probabilities. We show that the set of stationary equilibrium points is the union of a finite number of sets
such that, every element of each of these sets can be constructed from a finite number of extreme equilibrium strategies for
player I and from a finite number of pseudo-extreme equilibrium strategies for player II. These extreme and pseudo-extreme
strategies can themselves be constructed by finite (but inefficient) algorithms. Analogous results can also be established
in the more straightforward case of discounted single-controller games. 相似文献
39.
设Gi是满足第二可数性公理的、Hausdorff的、顺从的、r-离散的、主的局部紧群胚,并且有一个紧开G-集覆盖;设Pi是Gi中含G_i ̄0的开闭集,且满足及相应的模是具有性质DC的C(Gi)的子代数(i=1,2).本文证明从A(P1)到A(P2)上的每一个等距代数同构可以扩张成从C(G1)到C(G2)上的C-同构,进一步,可以对C(G2)重新坐标化,使得这个C-同构可由一个群胚同构生成. 相似文献
40.