简介：LetL~2([0,1],x)bethespaceoftherealvalued,measurable,squaresummablefunctionson[0,1]withweightx,andlet■_nbethesubspaceofL~2([0,1],x)definedbyalinearcombinationofJ_0(μ_kx),whereJ_0istheBesselfunctionoforder0and{μ_k}isthestrictlyincreasingsequenceofallpositivezerosofJ_0.Forf∈L~2([0,1],x),letE(f,■_n)betheerrorofthebestL~2([0,1],x),i.e.,approximationoffbyelementsof■_n.Theshiftoperatoroffatpointx∈[0,1]withstept∈[0,1]isdefinedbyT(t)f(x)=(1/π)∫_0~πf((x~2+t~2-2xtcosθ)~(1/2))dθ.Thedifferences(1-T(t))~(r/2)f=∑_(j=0)~∞(-1)~j(_j~(r/2))T~j(t)foforderr∈(0,∞)andtheL~2([0,1],x)-modulusofcontinuityω_r(f,τ)=sup{||(I-T(t))~(r/2)f||:0≤t≤τ}oforderraredefinedinthestandardway,whereT~0(t)=Iistheidentityoperator.Inthispaper,weestablishthesharpJacksoninequalitybetweenE(f,■_n)andω_r(f,τ)forsomecasesofrandτ.Moreprecisely,wewillfindthesmallestconstant■_n(τ,r)whichdependsonlyonn,r,andτ,suchthattheinequalityE(f,■_n)≤■_n(τ,r)ω_r(f,τ)isvalid.

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简介：证明了以Legendre多项式的极值点为插值结点组的Grünwald插值多项式在L2范数下是收敛的．

简介：Let{Y(t);t=(t1,t2)≥0}={Xk(t1,t2);t1≥0,t2≥0}k∞=1beasequenceoftwo-parameterOrnstein-Uhlenbeckprocesses(OUP2)withcoefficientsαk＞0,βk＞0.AFerniquetypeinequalityisestablishedandthesufficientconditionfora.s.l^2continuityofY(·)isstudiedbymeansoftheinequality.

简介：一新(2+1)维的格子方程被介绍在联合Toda格子和相对论的Toda格子(TL-RTL)的层次在开始的二个成员之上基于方程在(1+1)尺寸。为联合TL-RTLequations的层次的Darboux转变被构造。在联合TL-RTLequations的层次的开始的二个成员的答案，以及新(2+1)维的格子方程被theDarboux明确地获得转变。

简介：TwoseriesofterritremBanalogues(10a-10cand18)havebeendesignedandsynthesizedfromjujubogenin5awhichwaspreparedfromjujubogeninglycosides5bobtainedfromtheleavesofZizyphusjujuba.Thestructuresofthenewcompoundswereconfirmedby1H-,13C-NMRandMSdata.Compounds10cand18showedweakinhibitoryeffectonAChEat10^-4mol/E.

简介：TheauthorsdiscussproblemsofapproximationtofunctionsinL^2(R^n)andoperatorsfromL^2(R^n1)toL^2(R^n2)byRadial-BasisFunctions.TheresultsobtainedsolvetheparblemofcapabilityofRBFneuralnetworks,abasicprobleminneuralnetworks.

简介：The2-C,methylenegroupof1-aroyl-1,2-dihydro-3H-naphtho[2,1-b]pyran-3-ones(2)havebeenshowedtopossessasuperiorreactivitytowardsmanyoforganicreagents.Thena-phthopyrones(2)condensedwitharomaticaldehydestogivethe2-arylidinederivatives(3).Bromin-ationof2gave1,2-dibromo(4)or5-bromo(5)derivativesdependingonthereactionconditions.Thebasecatalyzedadditionorcycloadditionofnaphthopyrones(2)to4-methoxybenzalacetophenonegavetheexpectedMichaeladduct(6)orthecyclicadducts(7-9)dependingonthetypeofcatalyticbaseandreactionconditions.Structuresoftheproductshavebeenestablishedbyelementalanalyses,IRand~1HNMRspectroscopicmethods.

简介：Themononuclearcomplex,[NtCl2(trzCHzCHzCOPh)4]·6H2O(trz=1,2,4-triazole),wassynthesizedanditsstructurewasdeterminedbysinglecrystalX-raydetermination.Itcrystallizesinthemonoclinicsystem,spacegroupP21/c,withlatticepa-rameters:a=0.80391(2)nm,b=1.06215(2)nm,c=2.90133(2)nm,β=94.792(1)°andZ=2.EachnickelatomiscoordinatedbyfourNatomsoftriazolefromfourβ-(1,2,4-IriHole-1-yl)propiophenoneligandsandtwochlorideanionsinarrangementwithoctahedralcoordinationgeometry.Inadditiontothecoordinatingnickelcomplex,therearesixunco-ordinatedwatermolecules.TheNi—Ndistanceis0.24865(8)nmandtheNi—Ndistaneesareintherangeof0.2072(2)to0.2099(2)nm,respectively.Inthesolidstate,theUtiecom-poundformsthreedimensionalnetworkstructurethroughhy-drogenbonds.Theintermolecularhydrogenbondsconnectthe[NiCl2(C2H2N3CH2CH2COPh)4]andH2Omoieties.Thedeepgreencrystalswerealsoexaminedbyelementalanalysis,FT-IRandUVspectra,whichareinagreementwiththestructuralda-ta.

简介：给出了两种插值算子，并研究了它们在L^2πp和Lp(R)空间上的逼近阶，用实数α阶的积分模给出逼近度。

简介：DrivenbycuriosityaboutpossibleflightoptionsfortheChang’e-2spacecraftafteritremainsattheSun-EarthL2point,effectiveapproachesweredevelopedfordesigningpreliminaryfuel-optimalnear-Earthasteroidflybytrajectories.Theapproachesincludetheuseofmodifiedunstablemanifolds,gridsearchofthemanifolds’parameters,andatwo-impulsemaneuverfororbitalphasematchingandz-axisbiaschange,andaredemonstratedtobeeffectiveinasteroidtargetscreeningandtrajectoryoptimization.Asteroidflybysareexpectedtobewithinadistanceof2×107kmfromtheEarthowingtotheconstrainedEarth-spacecraftcommunicationrange.Inthiscase,thespacecraft’sorbitalmotionissignificantlyaffectedbythegravitiesofboththeSunandtheEarth,andtherefore,theconceptofthe"heliocentricoscillating-Keplerorbit"isproposed,becausetheclassicalorbitalelementsoftheflybytrajectoriesreferencedintheheliocentricinertialframeoscillatesignificantlywithrespecttotime.Theanalysisandresultspresentedinthisstudyshowthat,amongtheasteroidswhoseorbitsarethemostaccuratelypredicted,"Toutatis","2005NZ6",or"2010CL19"mightbeencounteredbyChang’e-2inlate2012or2013withtotalimpulseslessthan100m/s.

简介：为二子集W和Banach空间X的V，让Kn(W，V，X)相对旁边定义的V表示W的相对Kolmogorovn宽度

简介：LetGbealocallycompactAbeliangroupwithHaarmeasure.TheauthorsdiscusssomebasicpropertiesofL_(w_1)~r(G)∩L(p,q,w_2dμ)(G)spaces.ThenthenecessaryconditionsforcompactembeddingsofthespacesL_(w_1)~r(R~d)∩L(p,q,w_2dμ)(R~d)areshowed.

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简介：利用水热方法制备了一个新的过渡金属镉配合物[Cd（1，3-BDC）（L）（H2O）2]·H2O（1，3-H2BDC=间苯二甲酸，L=2-（3-吡啶基）-1H-苯并咪唑），并通过元素分析、红外光谱和X-射线单晶衍射方法确定了该配合物的晶体结构．结构分析表明该配合物属于单斜晶系，P21／c空间群，晶胞参数a=1．01641（6）nm，b=2．08842（12）nm，C=1．00l38（6）nm，β=106．3360（10）°，V=2．0398（2）nm3，Z=4，R1=0．0207，wR2=0．494．配合物中CdⅡ“离子与L配体的1个吡啶N原子、1，3-BDC的4个氧原子和2个配位水的O原子配位，形成七配位的扭曲十面体结构．配体1，3-BDC的桥连相邻的CdⅡ离子形成一维聚合物链，相邻链间通过氢键和π…π作用形成三维超分子网络，并对该配合物的热稳定性和荧光性质进行了研究．

简介：InthispaperL^p-L^qestimatesforthesolutionu(x,t)tothefollowingperturbedhigh-erorderhyperbolicequationareconsidered,(ρπ--a△)(ρπ--b△)u+V(x)u=O,x∈R^n,n≥6,ρ1eu(x,O)=O,ρ^3eu(x,O)=f(x),(j=O,1,2).WeassumethattheotentialV(x)andtheinitialdataf(x)arecompactlysupported,andV(x)issufficientlysmall,thenthesolutionu(x,t)oftheaboveproblemsatisfiesthesameL^p-L^qestimatesasthatoftheunperturbedproblem.

简介：Anonlinearparabolicsystemisderivedtodescribeincompressiblenuclearwaste-disposalcontaminationinporousmedia.Asequentialimplicittirne-steppingisdefined,inwhichthepressureandDarcyvelocityofthemixtureareapproximatedsimultaneouslybyamixedfiniteelementmethodandthebrine,radionuclidandheataretreatedbyacombinationofaGalerkinfiniteelementmethodandthemethodofcharacteristics.Optimal-orderconvergenceinL2isproved.Time-truncationerrorsofstandardproceduresarereducedbytimesteppingalongthecharacteristicsofthehyperbolicpartofthebrine,radionuclideandhealequalios,temporalandspatialerrorarelossenedbydirectcompulationofthevelocityinthemixedmethod,asopposedtodifferentiationofthepressure.

简介：Basedonthestructure-activityrelationshipsofRGD-containingpeptides,aseriesof1,3-dihydro-l,3-dioxo-2H-isoindolederivativesweresynthesized.Allofthemwerefirstreported.Theirstructureswereconfirmedbyspectraldataandelementalanalysis.Theirabilitytoinhibitangiogenesiswereevaluatedinthechickembryochorioallantoicmembraneassayat-10^-5mol/L.Compounds5band5edisplayedobviouslyantiangiogenicactivity.

简介：Theorientationoftheadditionof5-amino-3-benzylthio-1,2,4-triazoleanditsanalogues(pyrazole)(1)withthearylisocyanatecanbedirectedbycontrollingthereactiontemperatureandoneoftheproduct,5-amino-1-arylaminocarbonyl-3-benzylthio-1,2,4-triazole(pyrazole)(2),canrearrangeat170Ctoanotherproduct,5-arylureylene-3-benzylthio-1,2,4-triazole(pyrazole)(3).Aplausiblemechanismexplanationforthisrearrangementreactionwaspresented.Itwassuggestedthattherearrangementreactioncouldbereferredtothethermodynamicstranspositionleadingtothepredominant5-arylureylene-3-benzylthio-1,2,4-triazoleenergypreferentially.