简介:WereportQ-switchedandmode-lockederbium-dopedall-fiberlasersusingternaryReS2(1-x)Se2xassaturableabsorbers(SAs).ThemodulationdepthandsaturableintensityofthefilmSAare1.8%and0.046MW∕cm2.InQ-switchedmechanismoutput,thepulsewascenteredat1531.1nmwithmaximumpulseenergyandminimumpulsewidthof28.29nJand1.07μs,respectively.Inmode-lockedoperation,thepulsewascenteredat1561.15nmwithpulsewidthof888fs,repetitionrateof2.95MHz,andmaximumpulseenergyof0.275nJ.Tothebestofourknowledge,thisisthefirstreportonthemode-lockedEr3+-dopedfiberlaserusingternarytransitionmetaldichalcogenides.Thisworksuggestsprospective2D-materialSAscanbewidelyusedinversatilefieldsduetotheirattractiveoptoelectronicandtunableenergybandgapproperties.
简介:QuantumdynamicscalculationsforthetitlereactionH(2S)+S2(X3-Σg)→SH(X2Π)+S(3P)areperformedbyusingagloballyaccuratedoublemany-bodyexpansionpotentialenergysurface[J.Phys.Chem.A1155274(2011)].TheChebyshevrealwavepacketpropagationmethodisemployedtoobtainthedynamicalinformation,suchasreactionprobability,initialstate-specifiedintegralcrosssection,andthermalrateconstant.Itisfoundnotonlythatthereisareactionthresholdnear0.7eVinbothreactionprobabilitiesandintegralcrosssectioncurves,butalsothatboththeprobabilityandcrosssectionincreasefirstlyandthendecreaseasthecollisionenergyincreases.Theexistenceoftheresonancestructureinboththeprobabilityandcrosssectioncurvesisascribedtothedeeppotentialwell.Thecalculationoftherateconstantrevealsthatthereactionoccurringonthepotentialenergysurfaceoftheground-stateHS2isslowtotakeplace.
简介:Thecopolymersofchloroethylmethacrylate(CMA),glycidylmethacry-late(GMA),andmethylmethacrylate(MMA)weresynthesizedinbenzenesolution.Theirbreadthsofthemolecularweightdistributionsare2.1and2.3,respectivelyThether-malstabilityofP(GMA-CMA)issuperiortothatofP(CMA-MMA).TheresolutionsofP(CMA-MMA)andP(GMA-CMA)photoresistswerefoundtobe0.1~0.16μmand0.17~0.2μm,respectively.
简介:Synchrotronradiationsmall-angleX-rayscattering(SAXS)andtheviscositytechniquewereusedtoinvestigatetheeffectofdissolvedCO2intolueneontheconformationofpolystyrene(PS)inthesolution.TheviscosityofPSsolutiondecreasesfasterwithincreasingantisolventCO2pressurethanthatofthesolventintheabsenceofthepolymer.theintrinsicviscosity[η]calculatedusingthewellknownHugginsequationdecreaseswithantisolventpressure.ItwasfoundthatthesecondvirialcoefficientA2andtheapparentmean-squareradiusofgyration^1/2decreaseswithpressureofantisolventCO2.AllthesephenomenacanbeattributedtotheshrinkofPSchaininthecourseofaddingthegasantisolventbecausetheintercationbetweenthepolymerandsolventbecomesweaker.Thevalues^1/2atdifferentpressuresobtainedfromSAXSdataagreereasonablywiththosecalculatedfromFlorytheoryusingtheviscositydatadeterminedinthiswork.ThisimpliesthatFlorytheory,whichhasbeenusedwidelyforthesolutionsofpolymersinliquidsolvents,isalsoapplicabletothepolymersolutionwithgasantisolvent.
简介:ForquadraticnumberfieldsF=Q(√2pl…pt-1)withprimespj≡1mod8,theauthorsstudytheclassnumberandthenormofthefundamentalunitofF.TheresultsgeneralizenicelywhathasbeenfamiliarforthefieldsQ(√2p)withaprimep≡1mod8,includingdensitystatements.Andtheresultsarestatedintermsofthequadraticformx2+32y2andillustratedintermsofgraphs.
简介:在介绍B.VANROOTSELAAR的解方程组x′=Ax的一种新方法的基础上,对矩阵F(0)求法作了补充,对照以往通常的解法,分析了它的优越性.文章用完全开放性的Maple语言程序在计算机上实现了这种方法的应用,并通过生动的例子说明了同样是借助计算机强大的计算功能,新的解法在速度上要提高上百倍,更有实用价值.