简介:Ashortoverviewofthetheoryofaccelerationofthinfoilsdrivenbytheradiationpressureofsuperintenselasersispresented.Asimplecriterionforradiationpressuredominanceatintensitiesaround5×1020Wcm-2isgiven,andthepossibilityforfastenergygainintherelativisticregimeisdiscussed.
简介:寄生虫能影响他们的主人种类的许多方法是用途径的一个范围的强烈学习的焦点。在这上下文的一个特别地有希望却在使用得下面的方法是试验性的进化,因为它允许暴露于对比条件的已知的人口的指向的操作。把这个方法用于昆虫宿主和他们的联系寄生虫的学习的强壮的潜力被昆虫暴露于寄生虫的很少可得到的长期的实验表明。在这评论,我们总结这些研究,它响应寄生虫压力,内在的机制,以及相关基因回答交付了珍贵卓见进抵抗的进化。我们进一步在免疫,生活历史,和复制的互连的上下文从相关人工的选择研究估计调查结果。另外,我们更详细地讨论很多个学习得好的Triboliumcastaneum-Nosemawhiteicoevolution实验并且为研究提供建议。明确地,我们建议未来实验应该也用nonmodel主人被执行并且应该合并形成对照的试验性的条件,例如人口尺寸或环境。最后,我们期望那补充说例如,第三一秒合伙寄生虫或共生者,到一个主人寄生虫,系统能强烈影响(co)进化动力学。
简介:Thephotoacoustictomographybyusingthehandheldprobehasagreatpotentialinclinicalbreastimaging.However,theshapeoftheprobelimitsthechoiceoflightdeliveryinthissetup.Inthisletter,westudytwocommonlyusedilluminationtypesforhandheldprobe:bright-fieldilluminationanddark-fieldillumination.Ourresultsdemonstrateseveralparametershaveimportantimpactonthephotonfluenceindeepbreasttissue.Theresultswillhelptooptimizethedesignofthephotoacousticbreastimagingsystemwithahandheldprobe.
简介:Anintegratedmethodbasedonopticalanddigitalimageprocessingispresentedtosuppressspeckleindigitalholography.Aspatiallightmodulatorisadoptedtointroducerandomphasestotheilluminatingbeam.Multiplehologramsarereconstructedandsuperimposed,andtheintensityisaveragedtosmooththenoise.Theadaptivealgorithmbasedonthenonlocalmeansisdesignedtofurthersuppressthespeckle.Thepresentedmethodiscomparedwithothermethods.Theexperimentalresultsshowthatspecklereductionisimproved,andtheproposedmethodiseffectiveandfeasible.
简介:Earthquakeengineeringresearchanddevelopmenthavereceivedmuchattentionsincethefirsthalfofthetwentiethcentury.Thisvaluableresearchpresentedahugestepforwardinunderstandingearthquakehazardmitigation,whichresultedinappreciablereductionoftheeffectsofpastearthquakes.Nevertheless,the2011Tohokuearthquakeandthesubsequenttsunamiresultedinmajordamage.Thispaperpresentsthetimelineofearthquakemitigationandrecovery,asseenbytheauthors.Possibleresearchdirectionswheretheauthorsthinkthatmanyopenquestionsstillremainareidentified.Theseareprimarilybasedontheimportantlessonslearnedfromthe2011Tohokuearthquake.
简介:Two-dimensional(2-D)BiVO4nanosheets-graphene(GR)compositeswithdifferentweightadditionratiosofGRhavebeenpreparedviaafacilewetchemistryprocess.X-raydiffraction(XRD),Ramanspectra,X-rayphotoelectronspectra(XPS),UV-visdiffusereflectancespectra(DRS),field-emissionscanningelectronmicroscopy(FE-SEM),transmissionelectronmicroscopy(TEM),nitrogenadsorption-desorption,transientphotocurrentresponseandphotoluminescence(PL)spectrawereemployedtodeterminethepropertiesofthesamples.ItisfoundthatBiVO4nanosheetscouldpavewellonthesurfaceofgraphenesheets.BiVO4nanosheets-GRcompositeswithaproperadditionamountofGRexhibitedhigherphotocatalyticactivitythanbareBiVO4nanosheetstowardliquid-phasedegradationofrhodamineB(RhB)andmethylorange(MO)undervisiblelightirradiation.TheenhancementofphotocatalyticactivitiesofBiVO4nanosheets-GRcompositescanbeattributedtotheeffectiveseparationofphotoexcitedelectron-holepairs.Thisworknotonlyprovidesasimplestrategyforfabricatingspecific2-Dsemiconductor-2-DGRcomposites,butalsoopensanewwindowofsuch2-Dsemiconductor-2-DGRcompositesasvisiblelightphotocatalyststowardanimprovedvisiblelightphotoactivityinpurifyingpollutedwaterresources.
简介:Graphene(GR)-CdSnanocompositeswithdifferentweightadditionratiosofGRhavebeenassembledbyafacilesolvothermaltreatment.TheGR-CdSnanocompositephotocatalystwithanappropriateratioofGRexhibitsenhancedphotoactivityforselectivereductionofaromaticnitrocompoundstothecorrespondingaromaticaminesinwaterundervisiblelightirradiationascomparedwithblank-CdS.ThecharacterizationofGR-CdSnanocompositephotocatalystsbyacollectionoftechniquesdisclosesthat:i)GRcantunethemicroscopicmorphologyofCdSnanoparticlesandimprovelightabsorptionintensityinthevisiblelightregion;ii)GRscaffoldsactasanelectronreservoirtotrapandshuttletheelectronsphotogeneratedfromCdSsemiconductorunderthevisiblelightillumination;iii)theintroductionofGRenhancestheadsorptioncapacityofGR-CdSnanocompositestowardthesubstrates,aromaticnitrocompounds.ThesynergisticeffectofthesefactorsshouldaccountforthephotoactivityadvancementofGR-CdSnanocompositestowardtheprobereactions.Furthermore,becausethephotogeneratedholesinthesystemaretrappedbythequenchingagentammoniumoxalate,theas-obtainedGR-CdSphotocatalystisstableduringthephotocatalyticreductionreactions.Areasonablemodelhasalsobeenproposedtoillustratethereactionmechanism.
简介:Measurementoflightdistributioninbiologicaltissuecontributestoselectingstrategyandoptimizingdoseforbiomedicalapplication.Inthisletter,aphotoacousticmethodcombinedwithMonteCarlosimulationwasusedtoestimatethethree-dimensionallightdistributioninbiologicaltissue.Thelightdistributionwasproducedbyacylindricaldiffuserwhichinterposedintotissues.Thelightprofilesobtainedbythemethodwerecomparedtothosedetectedbyphotodiodes.Theexperimentalresultsdemonstratethefeasibilityofthismethod.Theapproachcanplayasignificantroleforphoto-dosimetryinbiomedicalphototherapy.
简介:Thesteadyanddynamicpropertiesarecomparativelyinvestigatedforthen-dopedandnon-dopedInGaNLEDs.Thesimulatedresultsshowthatthen-dopedLEDexhibitsthesuperiorluminescenceandmodulationperformance,whichismainlyattributedtothehighercarrierradiativerateofn-dopedLED.Theresultscanexplainthereportedexperimentalresultsperfectly.
简介:Weinvestigatetheeffectsofspontaneouslygeneratedcoherence(SGC)onboththesteadyandtransientgainpropertiesinafour-levelinverted-Y-typeatomicsysteminthepresenceofaweakprobe,twostrongcoherentfields,andanincoherentpump.Forthesteadyprocess,wefindthattheinversionlessgainmainlyoriginsfromSGC.Inparticular,wecanmodulatetheinversionlessgainbychangingtherelativephasebetweenthetwofields.Moreover,theamplitudeofthegainpeakcanbeenhancedandtheadditionalgainpeakcanappearbychangingthedetuningofthecouplingfield.Asforthetransientprocess,thetransientgainpropertiescanalsobedramaticallyaffectedbytheSGC.ComparedtothecasewithoutSGC,thetransientgaincanbegreatlyenhancedwithcompletelyeliminatedtransientabsorptionbychoosingtheproperrelativephasebetweenthetwofields.Andtheinverted-Y-typesystemwithSGCcanbesimulatedinbothatomicandsemiconductorquantumwellsystemsavoidingtheconditionsofSGC.
简介:Wefabricatewhitephosphorescentorganiclight-emittingdiodes(PHOLEDs)withthreedopantsanddoubleemissivelayer(EML)toachievecolorstability.ThewhitePHOLEDsuseFIrpicdopantforblueEML(BEML),andIr(ppy)3:Ir(piq)3dopantsforgreen:redEML(GR-EML)withN,N′-dicarbazolyl-3,5-benzene(mCP)ashostmaterial.ThicknessesofB-EMLandGR-EMLareadjustedtoformanarrowrecombinationzoneattwoEML’sinterfaceandchargetrappinghappensinEMLaccordingtowidehighestoccupiedmolecularorbitaland/orlowestunoccupiedmolecularorbitalenergybandgapofmCPandsmallerenergybandgapofdopants.ThetotalthicknessofbothEMLsisfixedat30nminthedevicestructureofITO(150nm)/MoO3(2nm)/N,N′-diphenyl-N,N′-bis(l-naphthyl-phenyl)-(l,l′-biphenyl)-4,4′-diamine(70nm)/mCP:Firpic-8.0%(12nm)/mCP:Ir(ppy)3-3.0%:Ir(piq)3-1.5%(18nm)/2′,2′,2′′-(1,3,5-benzinetriyl)-tris(1-phenyl-1-H-benzimidazole)(30nm)/8-hydroxyquinolinolato-lithium(2nm)/Al(120nm).WhitePHOLEDshows18.25cd/Aofluminousefficiencyandwhitecolorcoordinatesof(0.358and0.378)at5000cd/m2andcolorstabilitywithslightCIEXYchangeof(0.028and0.002)asincreasingluminancefrom1000to5000cd/m2.
简介:AnovelSr2CuInO3Soxysulfidep-typesemiconductorphotocatalysthasbeenpreparedbysolidstatereactionmethodanditexhibitsintriguingvisiblelightabsorptionpropertieswithabandgapof2.3eV.Thep-typesemiconductorcharacterofthesynthesizedSr2CuInO3SwasconfirmedbyHallefficientmeasurementandMott-Schottkyplotanalysis.First-principlesdensityfunctionaltheorycalculations(DFT)andelectrochemicalmeasurementswereperformedtoelucidatetheelectronicstructureandtheenergybandlocations.Itwasfoundthattheas-synthesizedSr2CuInO3Sphotocatalysthasappreciateconductionandvalencebandpositionsforhydrogenandoxygenevolution,respectively.Photocatalytichydrogenproductionexperimentsunderavisiblelightirradiation(λ>420nm)werecarriedoutbyloadingdifferentmetalandmetal-likecocatalystsonSr2CuInO3SandRhwasfoundtobethebestoneamongthetestedones.
简介:TiO2-loadedactivatedcarbonfibers(ACF)werepreparedbyahydrothermalmethod.Thesampleswerecharacterizedbyscanningelectronmicroscopy(SEM),X-raydiffraction(XRD),Fouriertransforminfrared(FT1R)spectrometryandUV-visdiffusereflectancespectra(DRS).SEMimagesshowedthattheTiO2nanoparticlesweredepositedonthesurfaceofACF,andtheparticlesizeandloadingamountofTiO2werevariedbychangingtheinitialconcentrationoftetrabutyltitanate(TBOT).TheresultsofanashexperimentshowedthattheloadingamountsofTiO2were18.4%,43.3%,52.5%,75.1%,and91.1%forinitialconcentrationsofTBOTof0.07,014,0.21,0.28,and0.35mol/L,respectively.PhysicalinteractionsplayedanimportantroleintheformationofTiO2/ACFcompositefibersthatabsorbUVandvisiblelight.ComparedwiththoseofACF,improvedadsorptionandphotocatalyticactivitytowardRhodamineB(RhB)wereobservedforTiO2/ACFcompositefiber.TheRhodamineBcouldberemovedefficientlybyTiO2/ACFcompositefibers,andtheTiO2loadingamounthadasignificanteffectonthephotocatalyticactivityofTiO2/ACFcompositefibers.