简介：Afacilesyntheticroutetotwoseco-eudesmane,4,5-dioxo-10-epi-4,5-seco-γeudesmane(1)and4,5-dioxo-10-epi-4,5-seco-γ-eudesmol(2)from(+)-dihydrocarvonehasbeendescribed.Avoidingexpensivereagents,thishighlyeconomicmethodespeciallysuitsforthesynthesisof4,5-seco-eudesman-typeandophianon-typesesquiterpeneswithadoublebondatposition11and12.

简介：在这篇论文，没有5电路并且没有距离的三角形，我们证明那是每张飞机图不到33-colorable。这改进Borodin和Raspaud的主要结果[Borodin，O.V.，Raspaud，A.：为平面图到的一个足够的条件是3-colorable。组合理论的杂志，重量的单位。B，88，17-27(2003)]，并且提供新上面的界限给他们的conjecture。

简介：我们综合了一系列Nb2Pd1xRuxS5多晶的样品由一固态反应方法并且系统地由运输和磁性的大小在超导性上调查了做Ru效果。超导性被提高，Ru做并且在混乱之上是相当柔韧的，这被发现。霍尔系数大小显示费用运输被类似于做的红外的案例的洞类型费用搬运人统治，建议多乐队超导性。在Ru或红外做之上，Hc2/Tc展出重要改进，超过泡利不相容原理由约4的一个因素的顺磁的限制价值。Tc和上面的关键字段的比较(在Pd地点上的不同的做元素之中的Hc2)，揭示联合的纺纱轨道的一个重要角色。

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简介：为isoxazolo的合成的一个快速、有效的方法[5,4-d]pyrimidin-4(5H)在与固体的常规加热和没有溶剂的微波照耀下面与orthoesters通过5-aminoisoxazole-4-carboxamides的出租机动三轮车冷凝作用被开发了酸催化。在比较，反应更快，收益在微波照耀下面是更高的。

简介：新奇pyridopyrazolopyrimidinone衍生物作为潜在的PDE5禁止者被设计并且综合。目标混合物比sildenafil对人的血小板PDE5，而是更少的有势力表明了重要禁止的活动。

简介：AbriefsurveyofformerandrecentresultsonHuber'sminimaxapproachinrobuststatisticsisgiven.TheleastinformativedistributionsminimizingFisherinformationforlocationoverseveraldistributionclasseswithupper-boundedvariancesandsubrangesarewrittendown.TheseleastinformativedistributionsarequalitativelydifferentfromclassicalHuber'ssolutionandhavethefollowingcommonstructure:(i)withrelativelysmallvariancestheyareshort-tailed,inparticularnormal；(ii)withrelativelylargevariancestheyareheavytailed,inparticulartheLaplace;(iii)theyarecompromisewithrelativelymoderatevariances.TheseresultsallowtoraisetheefficiencyofminimaxrobustproceduresretaininghighstabilityascomparedtoclassicalHuber'sprocedureforcontaminatednormalpopulations.Inapplicationtosignaldetectionproblems,theproposedminimaxdetectionrulehasprovedtoberobustandclosetoHuber'sforheavy-taileddistributionsandmoreefficientthanHuber'sforshort-tailedonesbothinasymptoticsandonfinitesamples。

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简介：Thispaperdealswiththecombinationofpointphononandphasonforcesappliedintheinteriorofinfiniteplanesandhalf-planesof1Dquasicrystalbi-materials.Basedonthegeneralsolutionofquasicrystals,aseriesofdisplacementfunctionsareadoptedtoobtainGreen'sfunctionsforinfiniteplanesandbi-materialplanescomposedoftwohalf-planesintheclosedform,whenthetwohalf-planesaresupposedtobeideallybondedortobeinsmoothcontact.Sincethephysicalquantitiescanbereadilycalculatedwithouttheneedofperforminganytransformoperations,Green'sfunctionsareveryconvenienttobeusedinthestudyofpointdefectsandinhomogeneitiesinthequasicrystalmaterials.

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简介：IntroductionInthepastseveralyears,muchresearchworkhasbeendoneforthesynthesisofC-fusedbicyclo-β-lactamcompoundsandaconcise“DoubleAnnulation”procedurehasbeendeveloped.Theβ-lactamringisformedbytheclassicalStaudingerreaction［1—3］betweenα-(alkylthio)acylchlorideandanequivalentα,β-unsaturatedimine.Thesulfurringissubsequentlyfusedontotheβ-lactamunitbymeansofahalogen-promotedheterocyclizationprocess［4—6］.ThisprocedurewasappliedtothesynthesisofpenemasillustratedinFig.1.TheobtainedX-penemsareakindofimportantintermediatesforsynthesizingaseriesofβ-lactamcompounds,forexample,theyarecarboxylatedbycouplingreactionsontheCatomwhichislinkedtohalagen,formingpenem［7］.Animportantpurposeintheresearchfieldistoprobeintonewβ-lactammedicines.

简介：Inthispaper,theauthorsstudytheCohen-Fischman-Westreich’sdoublecentralizertheoremfortriangularHopfalgebrasinthesettingofalmost-triangularHopfalgebras.

简介：In1929,AmericanastronomerHubblefirstdiscoveredthattherecessionalvelocityofagalaxyincreaseswithitsdistancefromtheearth,andthereforeputforwardHubble’slaw.ItisconsideredthefirstobservationalbasisfortheexpansionoftheuniverseandtodayservesasoneofthepiecesofevidencemostoftencitedinsupportoftheBigBangmodel.SincethentheastrophysicscommunityhasbelievedthattheuniverseisinaconstantrateofexpansionuntilSaulPermutter,BrianPaulSchmitandAdamGuyRieesdiscoveredtheacceleratingexpansionoftheuniversethroughobservationofseveraldozendistantsupernovasin1998,whothenwontheNobelPrizeinPhysics2011.Buthumanstillcannotcompletelyexplainthephenomenonthattheuniverseisexpandingatanever-acceleratingrate.Thustheauthorofthispaperstudiedtheoriginandevolutionofgalaxiesagain,andrevealedthestructureofgalaxyandprovedHubble’slaw,thenrevealedthetruthabouttheexpansionoftheuniverseaswellasdarkmatteranddarkenergy.

简介：Bothenantiomersofdenopamineweresynthesizedusingmicrobial-chemicalapproachviabioreductionof1-(acetoxyphenyl)ketone4(R=CH2C1)and5(R=CO2Et)withfungusGeotrichumsp.G38.

简介：ForEl-Nabulsi’sfractionalBirkhoffsystem,Meisymmetryperturbation,thecorrespondingMei-typeadiabaticinvariantsandNoether-typeadiabaticinvariantsareinvestigatedinthispaper.Firstly,basedonEl-NabulsiBirkhofffractionalequations,MeisymmetryandthecorrespondingMeiconservedquantity,NoetherconservedquantitydeducedindirectlybyMeisymmetryarestudied.Secondly,Mei-typeexactinvariantsandNoether-typeexactinvariantsaregivenonthebasisofthedefinitionofadiabaticinvatiant.Thirdly,Meisymmetryperturbation,Mei-typeadiabaticinvariantsandNoether-typeadiabaticinvariantsforthedisturbedEl-Nabulsi’sfractionalBirkhoffsystemarestudied.Finally,twoexamples,Hojman-UrrutiaproblemforMei-typeadiabaticinvariantsandanotherfortheNoether-typeadiabaticinvariants,aregiventoillustratetheapplicationoftheresults.

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简介：Ithasbeenwellknownthatfluorinatedpolyurethanesexhibituniquelylowsurfaceenergy,biocompatibilityandbiostability,thermalandoxidativestabilityandnonstickingbehavior.Consequently,thesepolymershaveattractedconsiderableinterest.However,themechanicalpropertiesoffluorinatedpolyurethanesusuallydeclinewithincreasingfluorinecontents.Theblendingoffluorinatedpolyurethaneswithnormalpolyurethanewascarriedouttoachievebalancedmechanicalandsurfaceproperties.Itwasfoundthatpolyurethanewithgoodmechanicalpropertiesandlowsurfaceenergycanbeobtainedbyaddingasmallamountoffluorinatedpolyurethane.Thefluorinatedsidechainscaneasilymigratetouppermostsurfacesoftheblendsuntillthefluorinelevelatthesurfacebecomesalmostsaturated.Ithasbeenshownfromcontactangle,XPSandAFMmeasurementsthatonlyaslittleas0.34wt%offluorinelevelisenoughtoproduceasurfacesaturatedwithfluorine,andthefluorinelevelattheuppermostsurfaceisonehundredtimeshigherthanthatintheblendbulk.Thefinaloutersurfacestructuresofthepolyurethaneblendwereindependentofthecontentofthefluorinatedpolyurethaneintheblendsduetothesurfacessaturatedbyfluorine.

简介：Amathematicalmodelofapredator-preymodelwithIvlev'sfunctionalresponseconcerningintegratedpestmanagement(IPM)isproposedandanalyzed.Weshowthatthereexistsastablepest-eradicationperiodicsolutionwhentheimpulsiveperiodislessthansomecriticalvalues,Furthermore,theconditionsforthepermanenceofthesystemaregiverl.Byusingbifurcationtheory,weshowtheexistenceandstabilityofapositiveperiodicsolution.Theseresultsarequitedifferentfromthoseofthecorrespondingsystemwithoutimpulses.Numericalsimulationshowsthatthesystemweconsiderhasmorecomplexdynamicalbehaviors.Finally,itisprovedthatIPMstrageyismoreeffectivethantheclassicalone.