简介：Theasymmetricalkylationsofchiraltransitionmetalcomplexesderivedfrom(+)-camphorand2-aminomethyl-6-methylpyridinewereexaminedundermildconditions.Theformationofthecomplexes2isconductivetotheenhancementofdi-astereoselectivityinthealkylationsatroomtemperature.

简介：ＴＨＥＥＦＦＥＣＴＯＦＴＨＥＩＮＴＥＲＡＣＴＩＯＮＡＭＯＮＧＭＵＬＴＩ－ＳＣＡＬＥＳＹＳＴＥＭＳＡＮＤＴＨＥＡＳＹＭＭＥＴＲＩＣＤＹＮＡＭＩＣＡＮＤＴＨＥＲＭＯＤＹＮＡＭＩＣＳＴＲＵＣＴＵＲＥＯＦＴＲＯＰＩＣＡＬＣＹＣＬＯＮＥＯＮＩＴＳＴＲＡＣＫＸｕ...

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简介：AsymmetryoftheWeiheBasinisdiscussedinthepaper,andalsothemastercontrolfault,secondarycontrolfaultofasymmetricbasinisproposedinthepaper.TheasymmetryoftheWeiheBasinisexpressedasfollows:(1)itsshapeofthecrosssectionsisasymmetrical;(2)thetectonicactivityofthesouthernmarginfaultandthenorthernmarginoneisapparentlydifferent;(3)itsdeeptectonicsisasymmetrical.Finally,weusetheWeiheBasinasanexampletoestablisha"cantilever-beam"modelforcalculations.Theresultsshowthat:(1)flexureleadstostressaccumulationandformingextensionalfractures;(2)fracturesslopesteeplytowardsthefreeend;(3)whenthelengthofbeambecomeslonger,itispossiblethatnewextensionalfractureswilloccurinthefixedend.

简介：一个周期的游戏系统的co进化的动力学为三种与不均匀的率在一个二维的方形的格子被调查。与混合得好的系统，共存和扑灭不同，在系统或者出现一零一个“行为为一种小人口尺寸是柔韧的，而，系统被共存为一张大人口支配一个。我们详细关于变化学习影响到状态的变化，并且发现关于变化和平均紧张的最大的振幅之间的差别决定系统最终是哪个状态。另外，我们介绍Potts精力解释原因零一个“行为。平均Potts精力每地点是距离到，这被显示出零一个“在模型的行为。

简介：Asimplifiedmodalmethodtoexplaintheresonancephenomenoninguidedmoderesonance(GMR)gratingswithasymmetriccoatingsispresented.Theresonanceobservedisduetotheinteractionoftwopropagationmodesinsidethegrating.Thereflectivityspectraandelectricfielddistributionscalculatedfromthesimplifiedmodalmethodarecomparedusingrigorouscoupled-waveanalysis(RCWA).Theinfluencesofhigh-orderevanescentmodesontheresonancepeakareanalyzed.AmatrixFabry-Perot(FP)resonanceconditionisdevelopedtoevaluatetheresonancewavelength.AnexplanationfortheresonancephenomenonobservedbasedontheFPresonancephaseconditionisalsoproposedanddemonstrated.ThesimplifiedmethodprovidesclearphysicalinsightsintoGMRgratingsthatareusefulfortheanalysisofavarietyofotherresonancegratings.

简介：Eleven(S)-(-)-bishydrocarbyl-(1-alkanoylpyrrolidin-2-yl)-methanolderivativesofthreetypesweresynthesizedfromL-proline,asymmtricallyselectivealkylationproductswereobtainedbyLDAtreatmentandalkylationusingmethyl2-bromoethylether,andthreetypesofchiralα-substituted-γ-butyrolactoneswereobtainedbyhydrolyzingthealkylationproducts,with%e.e.beingupto89percent.

简介：Introduction.Poly(N-vinylcarbazole)(PVCZ)hasreceivedmuchattentionasarepresentativephotoconductivepolymerandextensivestudiesonmechanical,physical,chemicalandelectricalpropertieshavebeenreported'’.Ingeneral,thePVCZobtainedbyradicalandordinarycanonpolym...

简介：AC2-symmetricalaryldiphosphitederivedfromchiralbinaphtholwaspreparedanditsrhodiumcomplexwasusedascatalystsintheasymmetrichydroformylationofolefins.Highcatalyticactivityandgoodregioselectivitywereobserved.Upto31.2%eeand38.1%eewereachievedforthehydroformylationof4-fluoro-styreneandvinylacetaterespectively.Theinfluencesofligand-to-metalratio,reactiontemperatureandthepressureofsyn-gasontheenantioselectivityandregioselectivitywerealsostudied.

简介：TheasymmetricinletvelocityprofilehasbeenobservedinphantommodelusingLDAandinhealthsubjectsusingMagnetResonance(MR).TheeffectsofasymmetricinletaxialvelocityprofileontheflowfieldandtheWallShearStress(WSS)ofcarotidbifurcationwerenumericallystudiedhereinwiththeTF-AHCBmodel.TheresultsshowthattheWallShearStressGradient(WSSG)inthefrontpartofthesinusforinward-tiltinginletaxialvelocityprofileisnearly2timesofthatforthesymmetriconeinthebeginningofsystole,theendofsystole,anddiastole,respectively.TheareaofWSSbelow5×10-3Paattheouterwallofthesinusforoutward-tiltinginletaxialvelocityprofileis1.5timesofthatfortheinward-tiltingoneduringdiastoleofthecardiaccycle.Theasymmetricinletvelocityprofilescanreducetheflowvelocityneartheinnerwallofthesinus,whichhasbeennormallyconsideredahighvelocityregion.Itisconcludedthatbesidesbifurcationgeometryandflowwaveform,theasymmetryofinletvelocityprofileisprobablyafactorinfluencingatherosclerosis.

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简介：Areusablecinchonaalkaloidderivativeligand,whichcouldbeeasilysynthesizedbytwosteptransformationwithcheap3,6-dichloropyridazineandquinineasmaterials,wasappliedtohomogeneousasymmetricdihydroxylationofolefinswithNMOasco-oxidantinMe2CO-H20systemandtheproductscouldbeextractedwithEt2Ofromtherecyclablecatalystsystem.80%---93%yieldand51%-99%eehavebeenobtained.Whentrans-stilbenewaschosenasthesubstrateforrecyclingexperiment,88%-92%yieldand>99%eehavebeenobtainedfortenrecycles.

简介：Theefiectsofmicroscopicthree-bodyforcesontheequatioilofstate(EOS)andthesingleparticlepropertiesofisospinasymmetricnuclearmatterhavebeenstudiedwithinBrueckner-Hartree-Fockframework~[1]Themicroscopicthree-bodyforcemodelconstructedfrommesonexchangecurrentapproachinRef.~[2]hasbeenextendedtoisospinasymmetricnuclearmatter

简介：新奇不对称的alkylaminoborazine单体，2-propylamino-4,6-bis(methylamino)borazine，第一次，并且直接被综合给melt-spinnablepolyborazine(PBN)的polymerized。这不对称的alkylaminoborazine被2,4,6-trichloroborazine(TCB)的aminolysis反应在温和条件下面与不同的胺综合。这条线路结果比常规线路便宜得多、简单。化学作文，结构，分子的重量和陶器的产量被EA，FTIR，NMR，GPC和TG分析调查。PBN为融化旋转展出合适的rheological性质，它建议它是为BN纤维的一位潜在的先锋。

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简介：Thechiralclusters(μ3-S)MCoW(CO)8[η^5-C5H4C(O)OCH3][M=Ru(2),Fe(3)]weresynthesizedbyasymmetricinductionofN-benzylcinchoniumchlorideasphase-transfercatalyst(PTC).ThemostsuitableamountofPTCis70mol%.Cluster3wasdeterminedbysinglecrystalX-raydiffractionanalysis.Thebesteeofthechiralclusterisover20%.

简介：Threenumericalexperimentshavebeencarriedoutbyusingaspectralbarotropicprimitiveequationmo-del.Itisfoundthattheresultsobtainedarequitesimilartothosewiththebarotropicfilteredmodel.Themainresultsreadasfollows:(1)Inthecasewithsymmetricorographyorwithoutorography,ifthemotionissymmetric(withre-specttotheequator,thesameistruehereafter)attheinitialinstant,thenitwouldbesymmetricafterwards.(2)Theantisymmetricorographydistributioncouldcauseantisymmetricmotion,andtheoriginalsym-metricmotionmightbecomeasymmetric.Inordertoexplaintheaboveresults,ithasbeenprovedthattheyaretheoreticallyvalid.Anditisfoundthatifthemotionisantisymmetricattheinitialinstant,thenitwouldbecomeasymmetric.Therefore,nopureantisymmetricmotioncouldbemaintained.

简介：Thequantitydiscountcontractsareinvestigatedforaone-supplier-one-retailersupplychainwithasymmetricinformationwhentheretailer'scostisdisrupted.Whiletheretailer'scoststructureisasymmetricinformation,twoall-unitquantitydiscountcontractmodels,fixedexpected-profitpercentagediscount(FEPD)andfixedwholesale-pricingpercentagediscount(FWPD)underasymmetricinformationareproposedinaregularscenario.Whentheretailer'scostdistributionfluctuatesduetodisruptions,the...

简介：由使用WRFmesoscale模型，这份报纸在在7月19日的时期期间登陆台风Haitang到20附近执行数字模拟和不对称的螺线雨乐队的结构的特征的诊断分析，2005。结果显示与降水中心联系的二根雨线主要台风中心向东北被定位。南部的雨线的运动和紧张与850-hPa相应很好从0200～1800UTC2005年7月19日的积极涡度乐队。在气旋的循环的效果下面，在850hPa的积极涡度乐队与一个南部的雨乐队一起连接了，导致在降水的南部的中心的降雨的增强。向南方的雨线逐渐地移动了向，加强在降水的北中心的降雨然后合并与向北方一个。而且，在重降雨之间的关系和分叉回答垂直砍在高高度的风被分析。最后，关系在低高度在降水的二个中心附近在对流涡度向量和降雨的垂直部件的发展之间被揭示。

简介：Themodulationofresonancefeaturesinmicrocavitiesisimportanttoapplicationsinnanophotonics.Basedontheasymmetricwhispering-gallerymodes(WGMs)inaplasmonicresonator,wetheoreticallystudiedthemodeevolutioninanasymmetricWGMplasmonicsystem.Exploitingthegapornano-scatterintheplasmonicringcavity,thesymmetryofthesystemwillbebrokenandthestandingwaveinthecavitywillbetunable.Basedonthisasymmetricstructure,theoutputcouplingratebetweenthetwocavitymodescanalsobetuned.Moreover,theproposedmethodcouldfurtherbeappliedforsensinganddetectingthepositionofdefectsinaWGMsystem.