简介：Inthispaper,analmostP-stabletwo-stepsixth-orderHybridmethodwithphase-lagoforderinfinityandaclassexpliciteighth-orderObreckoffmethodswithphase-lagoforder10-24aredevelopedforthenumericalintegrationofthespecialsecond-orderperiodicinitial-valueproblems.Thesemethodshavetheadvantageofhigheralgebraicorderandconsiderablysmallerphase-tagcomparedwithsomemethodsin[1-6].Numericalexamplesindicatethatthesenewmethodsaremoreaccuratethanmethodsdevelopedby[1-6].

简介：一个新上面、更低的答案理论为第二个顺序问题(G'(y))被介绍“+f(t，y)=0在有限、无限的间隔上。有限间隔上的理论基于一种Leray鈥揝chauder选择，而无限的间隔上的理论在有限间隔和一个diagonalization过程上基于结果。关键词上面、更低的答案-无限的间隔-diagonalization过程-Leray鈥揝chauder选择先生(2000)题目分类34B15-34B18-34B40由捷克的共和国的资助机构和捷克的政府J14/98:153100011的委员会的资助号码201/01/1451支持了

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简介：本文在对全息透镜的原理分析基础上,给出了一个简单实用的离轴全息透镜制作光路.

简介：Thedifferentregioselectiveandstereoselectiveproductswereobtainedbythereductionofstigmast-4,22-dien-3,6-dionewithNaBH4-CH3OHwhendifferentkindsofmetalionswasaddedtothereaction.

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

简介：Lophenol,cholest-4α-methyl-7-en-3β-ol(1),obtainedfromDracaenacochinchinensis(Lour.)S.C.Chen,wasstructurallymodified.Itwasacetylatedtoprotect3β-hydroxylgroup,andthenoxidisedbyseleniumdioxideinaceticacidtogivecholest-4a-methyl-8-en-3β,Ta-dioldiacetate(3).Thiscompound3isunstableinchloroformsolutionorwhenheatedandeasilyconvertedtoadienecompound,cholest-4a-methyl-7,14-dien-3β-olacetate(4).Thestructuresof3and4wereelucidatedbymeansofIR,^1HNMR,^13CNMRandMS,andtheabsoluteconfigurationof3wasestablishedbyX-raycrystallography.Thepropertyof3wasalsodiscussedinthispaper.Both3and4arenewcompoundsandwerereportedforthefirsttime.

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简介：Wepresenttheextendedhydrogenatomandmonopole-hydrogenatomtheorythroughgeneralizingtheusualhydrogenatommodelandwithamonopolemodelrespectively,inwhichY(sl(2))algebrasarerealized.WederivetheHamiltoniansofthetwomodelsbasedontheY(sl(2))andthegeneralizedPauliequation.TheenergyspectraofthesystemsarealsogivenintermsofYangianalgebraandquantummechanics.

简介：首先我们证明了,如果尺度函数有紧支集,来自多尺度分析的小波函数的支集形式.然后我们证明了Y.Meyer小波的尺度函数的一般形式.最后我们给出了它的另外两种形式和对应的Y.Meyer小波.

简介：本文介绍一种非跟踪式的由微处理器控制的轴角转换器的原理，对比分析了它与跟踪式轴角转换器的性能及特点。并附例供验证及参考。

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简介：计算狭缝和双棱镜之间的距离对折射光束单心性的影响，发现只有间距合理，干涉条纹才清晰易辨。

简介：让一，b，c，r被修理积极整数以便一(2)+b(2)=c(r)，min(一，b，c，r)>1和2转换了微小r。在这篇论文，我们证明那如果等价物到2(现代派4)，b等价物到3(现代派4)，c>3。10(37)并且r>7200，然后方程(x)+b(y)=c(z)仅仅有答案(x，y，z)=(2，2，r)。

简介：NewrareearthvanadatesYSrQ-xCaxV3O9-y（x=0.0,0.67,1.0,1.33and2.0）havebeensynthesizedbyanewsimplemethod.X-raypowderdiffractionresultsshowthattheyaremono-phase.Theybelongtoorthorhombicstructureandtheirlatticeconstantsarecalculated.TheresultsofweightgainsinTGcurvesshowthatthelowervalentvanadiumisoxidizedtohighervalentstateathighertemperature.Theoxygencontentsofnewcompoundsarecalculatedfromtheweightgains.BothV3+andV4+coexistinYSr2-xCaxV3O9-y.Thesecompoundsexhibitlowelectricresistivityatroomtemperature.

简介：本文设计一种断相保护电路。当电路工作正常时，发光二极管闪亮；电路缺相时，发光二极管不亮。同时，继电器触点断开，通过接触器切断电路使电机停止运行。

简介：ThispapersolvesanopenproblemofVaserstein.Themainresultis:theequationx^m+y^m=z^mhasasolutioninSL2zifandonlyifmisnotdivisibleby4or6andmisnotcongruentto3modulo6.

简介：ForquadraticnumberfieldsF=Q(√2pl…pt-1)withprimespj≡1mod8,theauthorsstudytheclassnumberandthenormofthefundamentalunitofF.TheresultsgeneralizenicelywhathasbeenfamiliarforthefieldsQ(√2p)withaprimep≡1mod8,includingdensitystatements.Andtheresultsarestatedintermsofthequadraticformx2+32y2andillustratedintermsofgraphs.

简介：采用水热方法合成一种新型钼-氧簇化合物Ni(en)3MoO4,并通过X射线单晶结构分析、红外光谱分析、元素分析、差热热重分析对该化合物进行了表征.结构分析数据表明:该化合物属三方晶系,P-31c空间群,晶胞参数a=0.9226(13)nm,b=0.9226(13)nm,c=0.9959(2)cm,α=90°,β=90°,γ=120°,V=0.7342(2)nm3,Z=2,Dc=1.805mg/m3,μ=2.153mm-1,F(000)=408,R=00553,Rw=0.1732;该化合物是分立结构,是由MoO4四面体簇和Ni(en)3八面体簇形成,其中MoO4四面体簇和Ni(en)3八面体簇交替排列,存在较强的氢键作用,结构中分立的手性配合物Ni(en)3的两种对映体构象以MoO4簇为中心对称排布.

简介：本文对圆筒形推拉式磁偶合器的磁力矩,进行了推导,对推导结果进行了分析.