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71 个结果
  • 简介:Blanketsandotherin-vesselcomponentsareeasilydamagedowingtotheircircumstanceofhighradiationandhighheat.Toprotectthem,firstwalldesignshouldbeconsidered.Owingtoitshighheatremovalndself-refreshingcapability,liquidmetalfirstwallhasbeenseenasapotentialfirstwallforafusionreactorinthefuture.Blanketliquidcurtainisactuallyaspecialliquidmetalwalltoprotectblanket.

  • 标签: 第一壁 金属流体 MHD 巨变堆材料 力学效应
  • 简介:Heattransferinthethrustchamberisofgreatimportanceinthedesignofliquidpropellantrocketengines.Regenerativecoolingisandadvancedmethodwhichcanensurenotonlytheproperrunningbutalsohigherperformanceofarocketengine.Thetheoreticalmodeliscomplicated,itrelatestofluidbynamics,heattransfer,combustion.etc…,Inthispaper,aregenerativecoolingmodelispresented.Effectssuchasradiation,heattransfertoenvironment,variablethermalpropertiesandcokingareincludedinthemodel.Thismodelcanbeappliedtoallkindsofliquidpropellantrocketenginesaswellassimilarconstructions.Themodularizedcomputercodeiscompletedinthework.

  • 标签: 液体火箭发动机 再生冷却 热传输系数
  • 简介:Weproposeadepolarizerbasedontheprincipleofacollectionofhalf-waveplateswithrandomlydistributedopticaxes.Thedesignisdemonstratedbymeansofdynamicallyphotopatterningliquidcrystalintorandomlyalignedhomogeneousdomains.Wecharacterizetheliquidcrystaldepolarizerfor1550nmandC-band(1520–1610nm).Adegreeofpolarizationoflessthan5%isobtainedforanylinearlypolarizedlight.Thisstudyprovidesapracticalcandidateforhigh-performancedepolarizers.

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  • 简介:Thisworkpresentsanumericalsimulationoftheflowfieldinaliquidpropellantrocketenginechamberandexitnozzleusingtechniquestoallowtheresultstobetakenasstartingpointsfordesigningthosepropulsivesystems.ThiswasdoneusingaFiniteVolumemethodsimulatingthedifferentflowregineswhichusuallytakeplaceinthosesystems.Astheflowfieldhasregionsrangingfromthelowsubsonictothesupersonicregimes,thenumericalcodeused,initiallydevelopedforcompressibleflowsonly,wasmodifiedtoworkproficientlyinthewholevelocityrange.ItiswellknownthatcodeshavebeendevelopedinCFD,foreithercompressibleofincompressibleflows,thejointtreatmentofbothtogetherbeingcomplexeventoday,giventhesmallnumberofreferencesavailableinthisarea.Hereanexistingcodeforcompressibleflowwasusedandprimitivevariables,thepressure,theCartesiancomponentsofthevelocityandthetemperatureinsteadoftheconservedvariableswereintroducedintheEulerandNavier-Stokesequations.ThiswasdonetopermitthetreatmentatanyMachnumber.Unstructuredmesheswithadaptiverefinementswereemployedhere.Theconvectivetermsweretreatedwithupwindfirstandsecondordermethods.ThenumericalstabilitywaskeptwithartificialdissipationandinthespatialcoverageoneusedafivestageRunge-KuttaschemefortheFluidMechanicsandtheVODE(ValueofOrdinaryDifferentialEquations)schemealongwiththeChemkinIIinthechemicalreactingsolution.Duringthedevelopmentofthiscodesimulatingtheflowinarocketengine,comparisontestsweremadewithseveraldifferenttypesofinternalandexternalflows,atdifferentvelocities,seekingtoestablishtheconfidencelevelofthetechniquesbeingused.ThesecomparisonsweredonewithexistingtheoreticalresultsandwithothercodesalreadyvalidatedandwellacceptedbytheCFDcommunity.

  • 标签: 喷管 数字模拟 液体燃料 火箭发动机
  • 简介:Thispaperreportsthedopingeffectofcholestericliquidcrystal3β-Hydroxy-5-cholestene3-oleateonpolymersolarcellscomposedofthepoly3-hexylthiopheneandthefullerenederivative.Withadopingratioof0.3wt%,thedeviceachievesanidealimprovementontheshuntresistorandthefillfactor.Comparedwiththereferencecell,thepowerconversionefficiencyofthedopedcellisimproved24%.Thephotoelectricmeasurementandtheactivelayercharacterizationindicatethattheself-assemblyliquidcrystalcanimprovethefilmcrystallizationandreducethemembranedefect.

  • 标签: 富勒烯衍生物 太阳能电池 胆甾液晶 掺杂效应 聚3-己基噻吩 填充因子
  • 简介:Inthelightofφ-mappingmethodandtopologicalcurrenttheory,theeffectofdisclinationlinesonthefreeenergydensityofnematicliquidcrystalsisstudied.ItispointedoutthatthetotalFrankfreeenergydensitycanbedividedintotwoparts.Oneisthedistortedenergydensityofdirectorfieldaroundthedisclinationlines.Theotheristhesaddle-splayenergydensity,whichisshowntobecentralizedatthedisclinationlinesandtobetopologicallyquantizedintheunitofkπ/2whentheJacobiandeterminantofthedirectorfielddoesnotvanishatthesingularitiesofthedirectorfield.ThetopologicalquantumnumbersaredeterminedbytheHopfindicesandBrouwerdegreesofthedirectorfieldatthedisclinationlines,i.e.,thedisclinationstrengthes.WhentheJacobiandeterminantvanishes,thegeneration,annihilation,intersection,splittingandmergingprocessesofthesaddle-splayenergydensityaredetailedintheneighborhoodsofthelimitpointsandbifurcationpoints,respectively.Itisshownthatthedisclinationlinewithhightopologicalquantumnumberisunstableandwillevolvetothelowtopologicalquantumnumberstatesthroughthesplittingprocess.

  • 标签: 旋转位移线 自由能量 结晶体 分歧理论
  • 简介:Thefinalgoaloffusionenergyresearchistomakeiteconomicallycompetitiveandthecostofelectricity(COE)aslowasacceptablebytheenergymarket.Thereforethefusionplasmahastobeoperatingwithhighpowerdensityandtheplasmafacingcomponents(PFC),suchasfirstwallanddivertor,havetosustainhighsurfaceheatloadandbombardmentwithhighparticleflux.SuchrigorousenvironmentsconsequentiallyleadtoseveredamageanderosionofPFCmaterials.Asaresult,thelifetimeofPFCwouldbeshortened.

  • 标签: 液态锂 燃料稀释 有效离子变换 等离子体
  • 简介:这篇论文报导了一有效;生产高度单音的驱散的CdSe量点(QD)的快速的方法,在哪个传统的trioctylphosphine氧化物(TOPO)是被石蜡液体代替溶剂;是的油的酸反应媒介。试验性的条件;QD的性质详细被学习了。产生样品与传播一致尺寸分发被证实电子显微镜学(TEM),当时紫外力的吸收;光致发光(PL)系列清楚地显示如此的综合QD有好荧光性质。

  • 标签: CDSE 光学性质 合成方法 量子
  • 简介:Wereportthemicrostructureevolutionofcopper(Cu)nm-sizedatomicislandsonsiliconeoilsurfacesintheambientatmosphere.Theoriginofthesenearlyfreesustainingatomicislandsisexplainedbyathree-stagegrowthmodel.Thefirststageisthenucleationandgrowthofatomicgranules.Subsequently,thecompactatomicislandsgrowbytheaggregationoftheatomicgranules.Finally,theyadheretoeachotherandformbranchedatomicislands.Duringthecharacteristicevolution,theatomicgranulesreconstructandtheaverageheightoftheatomicislandsincreasesfrom7.0±1.0nmto13.0±1.0nm.ThedetailedevolutionmechanismoftheCuatomicislandsispresented.

  • 标签: 铜原子 组织演化 大气环境 微观结构演变 聚集生长 环境大气
  • 简介:Helixunwindinginferroelectricliquidcrystalsinducedbyanelectricfieldistheoreticallystudiedonthebasisofthecontinuumtheory.Byapplyingaweakelectricfieldtiltedtothesmecticlayers,thecontributionofthedielectricinteractionenergydensitytothetotalfreeenergydensityisincreased.Approximationmethodsareusedtocalculatethefreeenergyfordifferenttiltanglesbetweentheelectricfieldandthesmecticlayers.Theobtainedresultssuggestselectingtheoptimalnumberofpitchesinthefilmthatmatchestotheminimumofthefreeenergy.

  • 标签: 电场诱导 铁电液晶 螺旋 连续介质理论 自由能密度 能量密度
  • 简介:控告的表面上的波浪运动一粘滞牛顿的液体作为一个起始值的问题被解决。漏的电介质和完美的绝缘的盒子被考虑。波浪的振幅被假定小。表面充电导致的电场被显示在表面波浪上有通常使动摇的效果。中立稳定性曲线被收(G,Ne)飞机(G:重力的契约数字;Ne:电的邦德数字)。Ohnesorge数字,Taylor-Melcher数字和介电常数比率几乎没在中立稳定性曲线上有小影响。古典正常模式方法不能在小时间预言波浪行为,这被证明。

  • 标签: 二维空间 波动 粘性液体 牛顿液体
  • 简介:Aliquidmodifiedphotoniccrystalfiber(PCF)integratedwithanembeddeddirectionalcouplerandmulti-modeinterferometerisfabricatedbyinfiltratingthreeadjacentairholesoftheinnermostlayerwithstandard1.48refractiveindexliquids.Therefractiveindexofthefilledliquidishigherthanthatofbackgroundsilica,whichcannotonlysupportthetransmittingrodmodesbutalsothe'liquidmodifiedcore'modespropagatingbetweenthePCFcoreandtheliquidrods.Hence,thelightpropagatingintheliquidmodifiedcorecanbeefficientlycoupledintothesatellitewaveguidesunderthephase-matchingconditions,resultinginadramaticdecreaseoftheresonantwavelengthintensity.Furthermore,thereisamulti-modeinterferenceproducedbymodifiedcoremodesandrodmodes.Suchacompact(~0.91cm)deviceintegratedwithanembeddedcouplerandinterferometerisdemonstratedforhigh-sensitivitysimultaneoustemperature(~14.72nm∕℃)andstrain(~13.01pm∕με)measurement.

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  • 简介:Experimentalresultsarepresentedforsuperfluid(HeⅡ)flowthroughporousplugliquid-vaporphaseseparators.Testshavebeenperformedonsevenporousplugswithdifferentthicknessesordifferentpermeabilities.Thetemperaturewasmeasuredfrom1.5Kto1.9K.Twoflowregionswereobservedinsmallandlargepressureandtemperaturedifferencesregionsrespectively.Theexperimentaldataarecomparedwiththeoreticalpredictions.Theperformanceandapplicabilityofthebasictheoryarediscussed.Hysteresisoftheflowrateisalsoobservedanddiscussed.

  • 标签: 超铃氦 超流体 流动率 液-气相位分离