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84 个结果
  • 简介:聚氨酯(PU)是目前合成材料中十分重要的品种,具有可发泡性、高弹性、耐磨性、高黏接性以及极好的绝缘性能,被广泛的应用在航天、电子、生物等领域作为胶黏剂、灌封剂、阻尼减震材料和生物高分子材料等。利用酸酐与聚氨酯预聚体的聚合反应合成了一系列的含有均苯四酸二亚胺结构的聚氨酯-亚胺(PUI),着重研究了均苯四酸二亚胺结构对共聚物的热性能和动态力学性能的影响。

  • 标签: 动态力学性能 嵌段聚氨酯 二酰亚胺 热性能 生物高分子材料 聚氨酯预聚体
  • 简介:Wetrytoapplyaconstituentquarkmodel(avarietychiralconstituentquarkmodel)andtheresonatinggroupapproachforthemulti-quarkproblemstocomputetheeffectivepotentialbetweentheNN-inS-wave(thequarksinthenucleonsNandN-,andthetwonucleonsrelativelyaswell,areinSwave)soastoseethepossibilityiftheremaybeatightboundstateofsixquarksasindicatedbyastrongenhancementatthresholdofpp-inJ/ψandBdecays.TheeffectivepotentialwhichweobtainintermsofthemodelandapproachshowsiftheexperimentalenhancementisreallycausedbyatightS-waveboundstateofsixquarks,thenthequantumnumberoftheboundstateisverylikelytobeI=1,JPC=0-+.

  • 标签: 核子-反核子效应 多夸克系统 夸克成分模型 BES 高能物理学
  • 简介:Low-energypartial-waveπNscatteringdataisreexaminedwiththehelpoftheproductionrepresentationofpartial-waveSmatrix,wherebranchcutsandpolesarethoroughlyunderconsideration.Theleft-handcutcontributiontothephaseshiftisdetermined,withcontrolledsystematicerrorestimates,byusingtheresultsofO(p^3)chiralperturbativeamplitudesobtainedintheextended-onmass-shellscheme.InSnandPuchannels,severediscrepanciesareobservedbetweenthephaseshiftdataandthesumofallknowncontributions.Statisticallysatisfactoryfitstothedatacanonlybeachievedbyaddingextrapolesinthetwochannels.WefindthataSnresonancepolelocatesat√zr=(0.895±0.081)—(0.164±0.023)iGeV,onthecomplexs-plane.Ontheotherhand,aFnvirtualpole,asanaccompanyingpartnerofthenucleonbound-statepole,locatesat√zv=(0.966±0.018)GeV,slightlyabovethenucleonpoleontherealaxisbelowthreshold.Physicaloriginofthetwonewlyestablishedpolesisexploredtothebestofoiirknowledge.ItisemphasizedthattheO(p^3)calculationgreatlyimprovesthefitqualitycomparingwiththepreviousO(p^2)one.

  • 标签: dispersion RELATIONS πN scatterings NUCLEON RESONANCE
  • 简介:由于碳化硼陶瓷具有强度高,耐高温等诸多优点,因此碳化硼陶瓷微球可实现微球的高压充气,但碳化硼微球不利用碳化硼陶瓷材料直接发泡成球,故采用先驱体聚合物转化法制备出聚合物微球,再陶瓷化得到碳化硼陶瓷微球。聚间亚苯基硼是一种较好的制备碳化硼陶瓷的先驱体聚合物,而制备聚合物微球时先驱体聚合物需要达到一定的分子量。利用改进的有机金属路线合成得到了较高产率的大分子有机硼烷.聚间亚苯基硼。

  • 标签: 先驱体聚合物 碳化硼陶瓷 亚苯基 合成 聚合物微球 陶瓷材料
  • 简介:Anenvironmentallyfriendlyprecursor,adenosine,hasbeenusedasadualsourceofCandNtosynthesizenitrogen-dopedcarboncatalystwith/withoutFe.Ahydrothermalcarbonizationmethodhasbeenusedandwateristhecarbonizationmedia.Themorphologyofsampleswith/withoutFecomponenthasbeencomparedbyHRTEM,andtheresultshowsthatFecanpromotethegraphitizationofcarbon.Furtherelectro-chemicaltestshowsthattheoxygenreductionreaction(ORR)catalyticactivityofFe-containingsample(C–FeN)ismuchhigherthanthatoftheFe-freesample(C–N).Additionally,theintermediatesofC–FeNformedduringeachsyntheticprocedurehavebeenthoroughlycharacterizedbymultiplemethods,andthefunctionofeachprocedurehasbeendiscussed.TheC–FeNsampleexhibitshighelectro-catalyticstabilityandsuperiorelectro-catalyticactivitytowardORRinalkalinemedia,withitshalf-wavepotential20mVlowerthanthatofcommercialPt/C(40wt%).Itisfurtherincorporatedintoalkalinepolymerelectrolytefuelcell(APEFC)asthecathodematerialandledtoapowerdensityof100mW/cm~2.

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  • 简介:方案1:“窝里K”成本:一部CD机,一副嗓子总需经费:CD机+唱片卡担是条狗,当钱包开始瘪的时候,我们开始强烈赞同冯大导演这句话。个人演唱会不是明星的专利啊,

  • 标签: 穷开心方法
  • 简介:ThenucleiaroundmagicnumberN=126areinvestigatedinthedeformedrelativisticmeanfield(RMF)modelwitheffectiveinteractionsTMA.WefocusinvestigationsontheN=126isotonicchain.TheN=126shellevolutionisstudiedbyanalyzingthevariationsoftwo-neutron(proton)separationenergies,quadrupledeformations,singleparticlelevelsetc.Thegoodagreementoftwo-neutronseparationenergiesbetweenexperimentaldataandcalculatedvaluesisreached.TheRMFtheorypredictsthatthesizesofN=126shellbecomesmallerandsmallerwiththeincreasingofprotonnumberZ.However,theN=126shellexistsinourcalculatedregionallalong.Accordingtothecalculatedtwo-protonseparationenergies,theRMFtheorysuggests~(220)Puisatwo-protondrip-linenucleusintheN=126isotonicchain.

  • 标签: 相对论平均场理论 演变 壳牌 质子数 分离能 计算值
  • 简介:AlineararrayofNmutuallycoupledsingle-modelasersisinvestigated.ItisshownthattheintensitiesofNlasersarechaoticallysynchronizedwhenthecouplingbetweenlasersisrelativelystrong.Thechaoticsynchronizationofintensitiesdependsonthelocationofthelasersinthearray.Thechaoticsynchronizationappearsbetweentwooutmostlasers,thesecondtwooutmostlasers,etc.Thereisnosynchronizationbetweennearestneighborsofthelasers.IfthenumberofNisodd,themiddlelaserisneversynchronizedbetweenanylasers.ThechaoticsynchronizationofphasesbetweennearestlasersinthearrayisexaminedbyusingtheanalyticsignalandtheGaussianfiltermethodsbasedonthepeakofthepowerspectrumoftheintensity.Itcanbeseenthatthemessageofchaoticintensitysynchronizationisconveyedthroughthephasesynchronization.

  • 标签: 混沌同步 密度相位 线性排列 固体激光器 非线性耦合
  • 简介:1-17 Vibrational Properties of Na_1-17VibrationalPropertiesofNa_¥ZhangFengsllou;E.SuraudlandR.GlowinskiZItisknownthatsmallso...

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  • 简介:N阶电阻网络等效电阻进行了研究,应用虚拟电流法给出了这类问题的两个普适规律,并将所得结果与其它相关结果进行了比较

  • 标签: N阶 电阻网络 虚拟电流 等效值
  • 简介:AschemeforcontrolledteleportationofanunknownN-qubitentangledGHZstatefromthesenderAlicetothedistantreceiverBobisproposed.Andm-qubitGHZstateissufficientforthetaskofcontrolbymspatially-separatedsupervisors.Conditionedonthelocaloperationsexecutedbyallparticipants,Bobcanfaithfullyrestoretheoriginalstatebyperformingrelevantunitarytransformationswiththeaidofsomeclassicalmessageaboutmeasurementresults.Anyone'sabsencewillabsolutelyleadtothefailureofteleportation.

  • 标签: 量子隐形传态 未知N-量子位 量子纠缠 GHZ态 BELL态测量