简介:ThispaperusesPoincaréformalismtoextendtheLevi-Civitatheoremtocopewithnonholonomicsys-temsadmittingcertaininvariantrelationswhoseequationsofmotioninvolveconstraintmultipliers.Sufficientcondi-tionsallowingsuchextensionareobtainedand,asanapplicationofthetheoryageneralizationofRouth’smotionispresented.
简介:BoththeexpansiveNewton'sinterpolatingpolynomialandtheThiele-Werner'sin-terpolationareusedtoconstructakindofbivariateblendingThiele-Werner'soscula-toryrationalinterpolation.Arecursivealgorithmanditscharacteristicpropertiesaregiven.Anerrorestimationisobtainedandanumericalexampleisillustrated.
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简介:TheformationmechanismfortheoctahedralcentralstructureoftheHe7^+clusterisproposedanditstotalenergycurveiscalculatedbythemethodofamodifiedarrangementchannelquantummechanics(MACQM).TheenergyisafunctionofseparationRbetweentwonucleiatthecenterandanapexoftheoctahedralcentralstructure.TheresultofthecalculationshowsthatthecurvehasaminimMenergy-19.7296a.u.atR=2.40α0.ThebindingenergyofHe7^+withrespecttoHe^++6Hewascalculatedtobe0.6437a.u.ThismeansthatthedusterofHe7^+maybeformedinthestableoctahedralcentralstructurewithR=2.40α0.
简介:AmethodforremovimgglucorapheninfromtheextractofRadishpigmentbyanionexchangeresin201×7wasstudied.Theadsorptioncapacityof201×7resinforglucorapheninwas72.8mg/mlresin,theequilibriumtime55minutes,andtheoptinumpH5.5.Allglucorapheninthathadbeenadsorbedon201×7resinwaselutedby1.5BV.hr^-1,eluentinwhincconcentrationofNaOHwas0.05mol·L^-1attheflowrateof1.5BV/h.Extractingsolutionofdeglucorapheninwasenrichedbyvacuumandspraydrying.ApowderproductofRadishpigmentwasobtainedandE1cm^1%=4.30.
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:ThisvolumeisdedicatedtoProfessorXiaqiDing,anacademicianoftheChineseAcademyofSciences,ontheoccasionofhiseightiethbirthday.ProfessorXiaqiDingwasbornonMay25,1928,inTaoJiangcounty,Hunanprovince.Hewasgraduatedin1951fromtheDepartmentofMathematics,WuhanUniversity.Becauseofhisoutstandingacademicperformance,hewasselectedrightaftercollegeforhisstudyandresearchat
简介:Inagasturbineenginecombustor,highlyswirlingcombustionisusuallyadoptedtostabilizeflameandreducepollutantemissions.Swirlcup,asanairblastatomizer,iswidelyusedtoprovideauniformpresentationoffueldropletstothecombustordome.Thispaperinvestigatedtheeffectofsecondaryswirlerontheflowfielddownstreamoftheswirlcupusingparticleimagevelocimetry(PIV).Threeswirlcups’non-reactingflowfieldwerestudied:caseA,BandCwithsecondaryswirlervaneangle53°,60°and68°respectively.Detailedmeanandtransientvelocitiesandvorticityinthecenterplanewereobtained.FromthePIVresults,asharpcontrastflowfieldwasobtainedforcaseAtoothertwocasesduetothelowersecondaryswirlingintensity.TherecirculationzoneiscollapsedindisorderforthecaseA.Ignitiontestsofthethreecupswerecompletedinasinglecupcombustor.Ingeneral,theignitionperformanceincreaseswiththeincreasingofthesecondaryswirlingintensity.ForcaseA,theignitionperformanceisveryunstableandhasmuchrandomnessandthereisnoclearleanignitionboundarycanbegenerated.Thisworkcanfurtherunderstandtheswirlbehaviorandignitionmechanism.
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.