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In this paper, we will discuss a class of integro-differential system of equations. It is a mathematicalmodel which is drown from the practical problems of the population control system with illness:where 0 相似文献   

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Isotactic polypropylene (iPP) with high content of ~ crystalline form was prepared by adding a series of new p form nucleators. The spherulites and morphology of//farm iPP (//-iPP) were investigated by wide-angle X-ray diffraction(WAXD), polarizing microscope (PLM), scanning electron microscope (SEM) and small-angle light scattering (SALS). WAXD experimental results indicate that the amount of p form in iPP (K_x) increases with increasing /~ nucleator content from zero to 0.07 wt% or crystallization temperature T_c from 20 to 120℃ and that the highest K_x value is up to 0.95. PLM observations suggest that p spherulites exhibit bright color and that their Maltese Crosses display some concentric banding of a rather spiky, jagged character. Their !amellae are smooth and relaxed layer-plate like structure by SEM and their SALS H_v patterns arc four-petalled.  相似文献   

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The following equations are basic forms of C-K equation (which is simplified in the following as singu-lar integral equations with convolution, that is C-K equations):where a,b,a_j,b_j are known constants or known functions, and find its solution f L_P(R), {0} or {α,β}.There were rather complete investigations on the method of solution for equations of Cauchy type aswell as integral equations of convolution type. But there is not investigation to the C-K equations, nodoubt, such that is important.  相似文献   

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Direct radiation grafting of acrylic acid (AA) and methacrylic acid (MAA) onto polyethylene (PE) films was studied. The investigation of the nature and characters of grafting proceeding was performed. The penetration of grafting onto the thin PE film was studied and the mechanism discussed. This involves an initial stage whereby the grafted surface layer deforms the PE allowing further monomer to penetrate. It was shown that the surface grafting was dynamic controlled and the penetration of monomer depended on the polarity of monomer.  相似文献   

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Multiphasesegmentedsiloxaneurethanecopolymershavebeenreportedintheliteraturewhichwerepreparedbyprimaryorsecondaryamineterminatedsiloxaneoligomerswithdiisocyanatesanddiols[1~6].However,becauseoftheintroductionofPDMSintothemainchainofpolyurethane,th…  相似文献   

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Recently,anewkindofinorganicporousmaterial—pillaredlayeredmetaloxidewasdeveloped.Comparedwithtraditionalpillaredclaysandmetalphosphates[1,2],thiskindofpillaredmaterialscanprovidemoreversatilestructuralandphysicalproperties,whichinturnwillfindwideapp…  相似文献   

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