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  • 简介:相遇次数的计算及其推广什邡市方亭三小罗天恩用作折线图的方法,求相遇的次数。这样做虽然直观,但如果作图不仔细就会出错,且从图中能获取的信息量较少。下面用分析的方法来解答相遇的次数问题。甲、乙两人在相距90米的直路上来回跑步。甲每秒跑3米,乙每秒跑2米。...

  • 标签: 什邡市 分析的方法 同向 花时间 路程差 两个公式
  • 简介:1.联系生活实例,认识杠杆是一根在力的作用下,可绕固定点转动的硬棒,能从常见的工具中辨识出杠杆.

  • 标签: 杠杆 生活实例 定点转动
  • 简介:Thesolidaddofthefirstprotonatedzincoborophosphate,(H3O)Zn(H2O)2BP2O8·H2O(1),wassoventothermallysyn-thesizedbythereactionofZn(NO3)2·6H2OandH3BO3withH3PO4inamixedsolvent,andstructurallycharacterizedbysingle-ystalX-raydiffractionanalysis.ItcrystallizesinthehexagonalP6122,a=0.9604(4)nm,c=1.5297(6)nm,V=1.2218(8)nm^3,Dc=2.921g/cm^3,Z=6,F(000)=1080,μ=3.495mm^-1.Thestmchwefeaturesthatthetetrahedra-te-trahedrahdlcesinterconnectedbyoctahedraandstronghydro-gembondinteractionsformathree-dimensionalframework.Theprotonatedwatermoleculesarelocatedatuniquepositions.othercharacterizationsbyIRandthermalanalysisarealsode-scribed.

  • 标签: (H3O)Zn(H2O)2BP2O8·H2O 合成 结构 质子化 螺旋带状物 硼磷酸锌化合物
  • 简介:Theobjectinthispaperistoconsidertheproblemofexistence,uniqueness,explicilrepresentationof(0,2)-interpolationonthezerosof(1-x2)Pn-1(x)/xwhennisodd,wherePn-1denotesLegendrepolynomialofdegreen-1,andtheproblemofconvergenceofinterpolatorypolynomials.

  • 标签: INTERPOLATION CONST UNIQUENESS details polynomial arbitrary
  • 简介:Wegiveaconstructionofthemaximum,andtheminimumofthesetofnondecreasmgapproxmantsinthediscretecase,whereisapositiveconoexfunction.Acharacterizationofthatsetisalsoobtained.

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  • 简介:On △I=4 Bifurcation PhenomenaOn△I=4BifurcationPhenomena¥ZhangJingye;YangSunandMikeGuidryTheexperiments-bythenew7--raydetector...

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  • 简介:让{X,Xn;n鈮?1}i.i.d的一个序列是随机变量,前=0,前2=蟽2<鈭?给Sn=X1+X2+吗?+Xn,Mn=最大k鈮鈭k鈭?n鈮?1。让n=O(1/木头木头n)。在这份报纸,我们证明那,为b>?1,

  • 标签: 切断法 随意变量 叠对数定律 序列
  • 简介:Inthispaperwestudytheaverageσ-Kwidthandtheaverageσ-linearwidthoftheunitballofl1x(R)inl2α(R).Theexactvaluesofthesewidthsarecalculatedandanoptimalsubspacewiththeoptimallinearopera-tor(fortheσ-linearwidth)areidentified.

  • 标签: exact inequality opera subspace AVERAGE R)IN
  • 简介:0.5%Pt-K/γ-Al2O3catalystsforthesynthesisofo-phenylphenol(OPP)fromo-cyclohexenyl-cyclohexanone(dimer)dehydrogenationwerepreparedbymeansofatwosubsequentimpregnationmethod.Theeffectsofcatalystpreparationparameters,suchasKpromoters,calcination,andreductionconditions,wereinvestigated.TheresultsshowedthattheadditionofK2SO4toPt/γ-Al2O3catalystnotablypromotedtheselectivityofOPP,anditsoptimumcontentwasfoundtobe6%inmassfraction.ThehigheractivitywasobtainedwhenPt/γ-Al2O3catalystwascalcinedinnitrogenatmosphereat400―500°Candthenreducedatthesametemperaturefor3hinhydrogenatmosphere.TheconversionofthedimerandtheselectivityofOPPwerealwaysabove99%and90%,respectively,over0.5%Pt-6%K2SO4/γ-Al2O3catalystduringthepilotscaletestof8000h.

  • 标签: 苯基苯酚 PT催化剂 K助催化剂 焙烧
  • 简介:WeuseMnforthesetofalln×nrealmatrices;(n)for{1,…,n};Snforthesymmetricgroupon〈n〉;A[α]α∈

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  • 简介:Theenantiomersofthirty-nineO-ethylO-phenylN-isopropylphosphoroamidothioateshavebeenseparatedbyhighperformanceliquidchromatographyonaPirklemodelchiralstationaryphaseusingtenmobilephase.Chromatographicdataarepresentedfortheseparationoftheseorganicphosphorusenantiomersonthechiralphase.Theinfluencesofmolecularstructuresandcompositionsofmobilephaseshavebeendescribed.

  • 标签: HPLC phosphorus ENANTIOMER SEPARATION PESTICIDE ENANTIOMERS
  • 简介:Thispaperstudiestheinteractionofshockandgradientwave(soundwave)ofsolutionstothesystemofinviscidisentropicgasdynamicsasamodelforthecorrespondingproblemsfornonlinearhyperbolicsystems.Theproblemcanbereducedtoaboundaryvalueprobleminawedgeddormain,ByusingthemethodofconstructingasymptoticsolutionsandNewton'siterationprocessitisprovedthatifaweakshockhitsagradientwave,thenthegrandientwavewillsplitintotwogradientwaves,whiletheshockcontinusespropagating.Inthispapertheauthorreducestheproblemtoastandardformandconstructsasymptoticsolutionoftheproblem.Theexistenceofthegenuinesolutionwillhegiveninthefollowingpaper.

  • 标签: 震动交感 声波 气体动力学 数学模型
  • 简介:Theauthorintroducesanotionofweak1sequencesandcharacterizessuchsequencesbymeansofhomologicalmethods.ThisnotionextendsthenotionofweekM-sequencesandthusextendsthenotionsofgeneralizedCohen-MacaulaymodulesandBuchsbaummodulestomoregeneralcases.

  • 标签: Noetherian局部环 上同调群 Koszul同调群 M序列