简介：Theaimofthisinvestigationwastodefinetheeffectivenessofnon-contactdryingusingultrasonicvibrations.Diskradiatorswereusedforcarryingoutexperiments,andaspecialdryingchamberwasdesignedtoprovideresonantamplificationofultrasonicvibrations(from130to150dB).Dryingofginsengandothervegetablesdemonstratedthattheapplicationofultrasonicvibrationsreducedpowerinputsby20%incomparisonwithconvectivedrying.Italsoledtoadecreaseof6%infinalmoisturecontent,ifthedurationofdryingwasconstant.Thelevelofintensificationofultrasonicdryingwashigh(upto50gfor1kgofdryingmaterial),whichhelpedtolowerthetemperatureofthedryingagentandimprovethequalityofthedriedproducts.

简介：Theprecipitationefficiencyanditsrelationshiptophysicalfactorsareexaminedbyanalyzingatwo-dimensionalcloud-resolvingmodelsimulationduringTOGACOAREinthisstudy.Thebasicphysicalfactorsincludeconvectiveavailablepotentialenergy,water–vaporconvergence,verticalwindshear,cloudratio,seasurfacetemperature,airtemperature,andprecipitablewater.Precipitationefficienciesdonotshowacloserelationshiptoairtemperaturenortoseasurfacetemperaturenortoprecipitablewater.Theprecipitationefficiencyincreasesasthewater–vaporconvergencerateincreasesandverticalwindshearweakens,whereasitdecreasesastheconvectiveavailablepotentialenergydissipatesandanvilcloudsdevelop.

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简介：Inrecentyearsperovskitesolarcellshaveattractedanincreasingscientificandtechnologicalinterestinthescientificcommunity.Itisimportanttoknowthatthetemperatureisoneofthefactorswhichhaveastrongeffectontheefficiencyofperovskitesolarcell.ThisstudycommunicatesatemperatureanalysisonthephotovoltaicparametersofCH_3NH_3PbI_3-basedperovskitesolarcellinabroadintervalfrom80to360K.Strongtemperature-dependentphotovoltaiceffectshavebeenobservedinthetypeofsolarcell,whichcouldbemainlyattributedtoCH_3NH_3PbI_3,showingaferroelectric-paraelectricphasetransitionatlowtemperature(T<160K).Anincreaseintemperatureovertheroomtemperaturedecreasedtheperovskitesolarcellperformanceandreduceditsefficiencyfrom16%to9%.Theinvestigationwithelectronicimpedancespectroscopyrevealsthatatlowtemperature(T<120K)thechargetransportlayerlimitsthedeviceperformance,whileathightemperature(T>200K),theinterfacialchargerecombinationbecomesthedominantfactor.

简介：三维的弄弯的多重槽的波导的弯曲效率被使用有效索引、修改的转移矩阵方法的一个联合方法学习。不对称的结构，不对称的槽，和弯曲效率上的不对称的中间的脱衣的效果被调查。我们证明弯曲效率能被不对称的结构和不对称的中间的脱衣的使用改进。不同的槽波导的弯曲效率(直到五倍槽的结构)被比较。尽管单个槽的波导一般来说为一样的波导参数提供最低弯曲损失，多重槽的波导能比单个槽的介绍更低的弯曲损失，是可能的，这被揭示。

简介：Wepresentahighlyefficientmethodofgeneratingandshapingellipseperfectvectorbeams(EPVBs)withaprescribedellipseintensityprofileandcontinuouslyvariantlinearpolarizationstate.Theschemeisbasedonthecoaxialsuperpositionoftwoorthogonallypolarizedellipselaserbeamsofcontrollablephasevortexservingasthebasevectorcomponents.Thephase-onlycomputer-generatedhologramisspecificallydesignedbymeansofamodifiediterationalgorithminvolvingacomplexamplitudeconstraint,whichisabletogenerateanEPVBwithhighdiffractionefficiencyinthevectoropticalfieldgenerator.WeexperimentallydemonstratethattheefficiencyofgeneratingtheEPVBhasanotableimprovementfrom1.83%intheconventionalcomplexamplitudemodulationbasedtechniqueto11.1%inourmethod.WealsodiscussanddemonstratethesimultaneousshapingofmultipleEPVBswithindependenttunableellipticityandpolarizationvortexinbothtransversal(2D)andaxial(3D)focusingstructures,provingpotentialsinavarietyofpolarization-mediatedapplicationssuchastrappingandtransportationofparticlesinmorecomplexgeometriccircumstances.

简介：有效的氨兆兆赫(THz)洞激光试验性地被报导。不同于象洞couplers和独立网孔couplers那样的过去的设计计划，在我们的系统，输入和输出couplers被扔镍制作ZnSe和高抵抗力的硅底层上的电容的金属性的网孔。因此couplers能不仅作为一个F-P振荡器被构造而且能是封上更容易执行排列的调整与的窗户被使用。为了提高THz激光，输出精力和光子变换效率，象泵紧张那样的主导的因素和煤气的压力试验性地被调查。最后，有在1.09kPa操作的90m波长(3.33THz)的氨激光的1.35mJ兆兆赫放射与9R(16)由402mJ茶CO2激光抽了线被产生，并且6.5%的光子变换效率被完成。

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简介：在教学中，经常会遇到条件不明确的问题，学生常顾此失彼，导致少解或漏解，这需要对不明确条件逐一分析讨论、做出正确的判断，这就是物理中的分类思想。

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简介：Inordertoestimatethecut-sizeXcandthemechanicallybalancedparticlesintheaxialflowcyclonewiththeslit-separationmethod,thetangentialvelocitydistributionswerecalculatedbythefinitedifferencemethod.Incomparisonofthecalculatedresultsofthetotalcollectioneffciencywiththeexperimentalresults,thecalculatedresultsshowedalittlehigherthantheexperimentalresultsduetothere-entrainmentofthecollectedparticlesbyturbulence.Theeffectoftheslitforpromotingthecollectionefficiencywasnotrecognized.

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简介：Four-wavemixing,aswellasitsinducedintensitynoise,isharmfultowavelengthdivisionmultiplexingsystems.Theefficiencyandtherelativeintensitynoiseoffour-wavemixingarenumericallysimulatedforthetwo-waveandthethree-wavefibertransmissions.Itisfoundthattheefficiencydecreaseswiththeincreaseofboththefrequencyspacingandthefiberlength,whichcanbeexplainedusingthequasi-phase-matchingcondition.Furthermore,therelativeintensitynoisedecreaseswiththeincreaseoffrequencyspacing,whileitincreaseswiththeincreaseoffiberlength,whichisduetotheconsiderablepowerlossofthepumplight.Thisinvestigationpresentsagoodreferenceforthepracticalapplicationofwavelengthdivisionmultiplexingsystems.

简介：在一篇最近的文章[物理信A372(2008)417]，王等。建议了一个方法，它被叫(G'/G)扩大方法，寻找非线性的进化方程的旅行波浪答案。包含KdV方程，mKdV方程，变体Boussinesq方程，和Hirota一种奶油色的陶器方程的参数的旅行波浪解决方案被使用这个方法获得。他们想(G'/G)扩大方法是一个新方法和许多非线性的进化方程的更多的旅行波浪答案能被获得。在这篇论文，我们将证明(G'/G)扩大方法等价于扩大tanh功能方法。

简介：Theroleofreducedgrapheneoxide(rGO)intheenhancementofphoto-conversionefficiencyofZnOfilmsforphotoelectrochemical(PEC)water-splittingapplicationswasanalyzed.ZnOandrGO-hybridizedZnO(rGO/ZnO)filmswerepreparedviaatwo-stepelectrochemicaldepositionmethodfollowedbyannealingat300°Cunderargongasflow.Thephysical,opticalandelectrochemicalpropertiesofthefilmswerecharacterizedtoidentifytheeffectofrGO-hybridizationontheappliedbiasphoton-to-currentefficiency(ABPE)ofZnO.ScanningelectronmicroscopyandX-raydiffractionindicatedtheformationofverticallyaligned,wurtzite-phaseZnOnanorods.Diffuse-reflectanceUV–visiblespectroscopyindicatedthatrGO-hybridizationwasabletoincreasethelightabsorptionrangeoftherGO/ZnOfilm.UPSanalysisshowedthathybridizationwithrGOincreasedthebandgapofZnO(3.56eV)to3.63eVforrGO/ZnOsample,whichmaybeattributedtotheBurstein–Mosseffect.Photoluminescence(PL)spectradisclosedthatrGOhybridizationsuppressedelectron-holerecombinationduetocrystaldefects.Linearsweepvoltammetryofthepreparedthinfilmsshowedphotocurrentdensityof1.0and1.8mA/cm~2forZnOandrGO/ZnOat+0.7V,whichcorrespondedtoanABPEof0.55%and0.95%,respectively.Thus,thisreporthighlightedthemulti-facetedroleofrGO-hybridizationintheenhancementofZnOphoto-conversionefficiency.

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简介：Wepresentthedesignandexperimentofabroadbandopticalparametricchirped-pulseamplifier(OPCPA)whichprovideshighconversionefficiencyandgoodbeamqualityat808nmwavelength.Usingathree-dimensionalspatialandtemporalnumericalmodel,severaldesignconsiderationsnecessarytoachievehighconversionefficiency,goodbeamqualityandgoodoutputstabilityarediscussed.Toimprovetheconversionefficiencyandbroadentheamplifiedsignalbandwidthsimultaneously,thenonlinearcrystallengthandOPCPAparametersareanalyzedandoptimizedwiththeconceptofdissipatingamplifiedidlerbetweenopticalparametricamplification(OPA)oftwocrystalsconfiguration.Intheexperiment,anamplifierconsistingoftwoOPCPAstagesof‘L’typeconfigurationwasdemonstratedbyusingtheoptimizedparameters.Anamplifiedsignalenergyof160mJwasachievedwithatotalpump-to-signalefficiencyof35%(43%efficiencyfortheOPCPAstage2).Theoutputbandwidthofsignalpulsereached80nmandthesignalpulsewascompressedto24fs.Theenergystabilityreached1.67%RMSat3%pumpenergyvariation.TheoptimizedOPCPAamplifieroperatesatarepetitionrateof1Hzandisusedasafront-endinjectionforthemainamplifierofSG-II5PWlaserfacility.

简介：Quantumdots(QDs)canachievehighquantumyieldsclosetounityinliquidsolutions,whereastheyexhibitadecreasedconversionefficiencyafterbeingintegratedintosolid-statepolymermatricesforlight-emittingdiode(LED)devices,whichiscalledthehostmatrixeffect.Inthisstudy,weproposeasolid–liquidhybrid-stateQD-LEDtosolvethisissue.Theethylene-terminatedpolydimethylsiloxane(ethylene-PDMS)isusedtoestablishasolid-statecross-linkednetwork,whereasthemethyl-terminatedPDMS(methyl-PDMS)isusedinitsliquidstate.Fromamacroscopiclevel,thecuredsolid–liquidhybrid-statePDMS(SLHP)compositesreachasolidstate,whichisstableandflexibleenoughtobeusedinLEDdevices.ComparedwithLEDsusingconventionalQD/solidPDMScompositesatequalcolorconversionefficiencyrangingfrom40%to60%,theluminousfluxofLEDswithQD/SLHPcompositesisincreasedby13.0%usinganoptimizedmethyl-PDMSconcentrationof85wt.%.Asaresult,highefficiencyQD-LEDsusingQDsastheonlycolorconvertorwithluminousefficacyof89.6lm/W(0.19A)wereachieved,whichshowaworkingstabilitycomparablewiththatusingconventionalsolid-statestructuresataharshcondition.Consequently,thenovelapproachshowsgreatpotentialforachievinghighefficiencyandhighstabilityQD-LEDs,whichisalsocompatiblewithcurrentstructuresusedinilluminationanddisplayapplications.