简介:本文得到几个关于多变量Hp空间中函数Fourier系数的不等式.与单变量相应情形相比,我们的证明方法有较大的变化.
简介:ThenonconformingWilson’sbrickclassicallyisrestrictedtoregularhexahedralmeshes.LesaintandZlamal[6]relaxedthisconstraintforthetwo-dimensionalanalonueofthiselementInthispaperweextendtheirresultstothreedimensionsandprovethatandwhereuistheexactsolution,u_histheapproximatesolutionandistheusualnormfortheSobolevspaceH~1(?).
简介:Baker'syeastmediatedreductionofopticallyactivediketoneisdescribed.Thetwoketogroupsareefficientlydifferentiatedandtheeevalueoftherecoveredmaterialisconsiderablyraised.Itaffordshighlyopticallyactivekeyintermediatesefficientlyforthesynthesisofnaturalpolyhydroxylatedagarofuranproducts.
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简介:Inthisworkweslwlylinearpolynomialoperatorspreservingsomeconsecutivei-convexitiesandleavingin-verantthepolynomtalsuptoacertaindegree.Firstwestudytheexistenceofanincompatibilitybetweentheconservationofcenaini-cotivexitiesandtheinvarianceofaspaceofpolynomials.InterpolationpropertiesareobtainedandatheorembyBerensandDcVoreabouttheBernstein’soperatortsextended.Finally,fromtheseresultsagenera’izedBernstein’soperatorisobtained.
简介:ThispaperusesPoincaréformalismtoextendtheLevi-Civitatheoremtocopewithnonholonomicsys-temsadmittingcertaininvariantrelationswhoseequationsofmotioninvolveconstraintmultipliers.Sufficientcondi-tionsallowingsuchextensionareobtainedand,asanapplicationofthetheoryageneralizationofRouth’smotionispresented.
简介:牛顿的重复为单个Toeplitz矩阵的组逆的计算被修改。在每次重复,重复矩阵被一个矩阵与一个低排水量等级接近。因为重复矩阵的排水量结构,涉及牛顿的重复的thematrix向量增加能高效地被做。我们证明修改牛顿重复的集中仍然是很快的。数字结果被介绍表明建议方法的快集中。
简介:Small-angleX-rayscattering(SAXS)usingsynchrotronradiationasX-raysourcehasbeenemployedtocharactcizcthemicroscopicstructrureoforgano-modifiedmesoporousmolecularsieves(organo-MSU-X)preparedbyaone-pottemplate-directedsynthesis.ItisshownthattheSAXSprofileishardlyconstantwithPorod’slawshowinganegativeslope,i.e.,negativedeviation.Thissuggeststhatthereisdiffuseinterfaciallayerlocatedbetweentheporesandthematrix.Thissuggeststhattheorganicgroupsremaincovalentlylinkedtothematrix,asindicatedby^29SiCPMASNMRandFT-IR.Theaveragethicknessoftheinterfaciallayerwasfoundtobeabout1nmforeachofthethreesampleswithdifferentkindsandthesameamounts(20?oforganicgroups.Thiskindofmaterialhasalsobeenprovedtopossessbothsurfaceandmassfractalstructureoftheamophousporoussilicamaterials.2001ElsevierScienceB.V.Allrightsreserved.
简介:The1/3subharmonicsolutionfortheDuffing'sequationisinvestigatedbyusingthemethodsofharmonicbalanceandnumericalintegration.Thesensitivityofparametervariationforthetransientprocessandthetransientprocessfortheperturbanceinitialconditionsarestudied.Overandabove,theprecisionofnumericalintegrationmethodisdiscussedandthenumericalintegrationmethodiscomparedwiththeharmonicbalancemethod.Finally,asymptoticalstabilityofthepuresubharmonicoscillationselementisinspected.