简介:LargeapertureNd:phosphatelaserglassisakeyopticalelementforaninertialconfinementfusion(ICF)facility.N31,onetypeofneodymiumdopedphosphateglasses,wasdevelopedforhighpeakpowerlaserfacilityapplicationsinChina.ThecompositionandmainpropertiesofN31glassaregiven,togetherwiththoseofLHG-8,LG-770,andKGSS-0180Nd:phosphatelaserglasses,fromHoyaandSchott,andfromRussia.Thetechnologiesofpotmelting,continuousmelting,andedgecladdingoflargesizeN31phosphatelaserglassarebrieflydescribed.ThesmallsignalgainprofilesofN31glassslabsfrombothpotmeltingandcontinuousmeltingatvariousvaluesofthepumpingenergyofthexenonlamparepresented.N31glassischaracterizedbyastimulatedemissioncrosssectionof3.8×10-20cm2at1053nm,anabsorptioncoefficientof0.10–0.15%cm-1atlaserwavelength,smallresidualstressaroundtheinterfacebetweenthecladdingglassandthelaserglass,opticalhomogeneityof~2×10-6ina400mmaperture,andlaserdamagethresholdlargerthan42J/cm2fora3nspulsewidthat1064nmwavelength.
简介:Thediscretizationsizeislimitedbythesamplingtheorem,andthelimitisonehalfofthewavelengthofthehighestfrequencyoftheproblem.However,onehalfofthewavelengthisanidealvalue.Ingeneral,thediscretizationsizethatcanensuretheaccuracyofthesimulationismuchsmallerthanthisvalueinthetraditionalfiniteelementmethod.Thepossiblereasonofthisphenomenonisanalyzedinthispaper,andanefficientmethodisgiventoimprovethesimulationaccuracy.
简介:ThisarticledescribesalocalerrorestimatorforGlimm'sschemeforhyperbolicsystemsofconservationlawsandusesittoreplacetheusualrandomchoiceinGlimm'sschemebyanoptimalchoice.Asaby-productofthelocalerrorestimator,theprocedureprovidesaglobalerrorestimatorthatisshownnumericallytobeaveryaccurateestimateoftheerrorinL1(R)foralltimes.Althoughthereispartialmathematicalevidencefortheerrorestimatorproposed,atthisstagetheerrorestimatormustbeconsideredad-hoc.Nonetheless,theerrorestimatorissimpletocompute,relativelyinexpensive,withoutadjustableparametersandatleastasaccurateasotherexistingerrorestimators.Numericalexperimentsin1-DforBurgers'equationandforEuler'ssystemareperformedtomeasuretheasymptoticaccuracyoftheresultingschemeandoftheerrorestimator.
简介:<正>InthepresentnotethealgebraicindependenceofvaluesofseveralMahlerserieswithcertainparticularanddifferentparametersatalgebraicpointsisestablishedbymeansofatypicalapproximationmethodhandlingtheLiouvilletypeseries.
简介:InthispaperwediscusstheconvergenceofamodifiedNewton’smethodpresentedbyA.Ostrowski[1]andJ.F.Traub[2],whichhasquadraticconvergenceorderbutreducesoneevaluationofthederivativeateverytwostepscomparedwithNewton’smethod.Aconvergencetheoremisestablishedbyusingaweakconditiona≤3-2(21/2)andasharperrorestimateisgivenabouttheiterativesequence.
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简介:Toeffectivelysolvetheagglomerationproblemsinthesolidstatereactionprocess,pre-addingglucoseisadoptedtothesynthesisofLiFePO4/CenergymaterialsusingFe–Pwasteslag.Theaverageparticle&grainsizeofLiFePO4/Cdecreases,andtheimpuritiesinLiFePO4/Ccompositesreducetoagreatextent.Itmakesgreatsensetothemassindustrialproduction.Theoptimumsynthesisconditionsdeterminedinthisworkarebasedontheorthogonalexperiments.Thesamplessynthesizedinascaleof500gexhibithighpurity,excellentelectrochemicalperformance,highreactionactivity,goodreversibility,andlowpolarizationlevel.Thedischargecapacitiesare145,134,117,and102mAh/gatthecurrentdensitiesof0.1C,0.2C,0.5Cand1C,respectively.ThisworkputsforwardapracticalsuggestionformassproducingenvironmentalbenignandlowcostLiFePO4/Cascathodematerialsoflithiumionbatteries.
简介:Thefirstexperimentalmeasurementsofintense(~7×1019Wcm-2)laser-driventerahertz(THz)radiationfromasolidtargetwhichispreheatedbyanintensepulseoflaser-acceleratedprotonsisreported.ThetotalenergyoftheTHzradiationisfoundtodecreasebyapproximatelyafactorof2comparedtoacoldtargetreference.Thisisattributedtoanincreaseinthescalelengthofthepreformedplasma,drivenbyprotonheating,atthefrontsurfaceofthetarget,wheretheTHzradiationisgenerated.TheresultsshowtheimportanceofcontrollingthepreplasmascalelengthforTHzproduction.
简介:Akindofsecond-orderimplicitfractionalstepcharacteristicfinitedifferencemethodispresentedinthispaperforthenumericallysimulationcoupledsystemofenhanced(chemical)oilproductioninporousmedia.Sometechniques,suchasthecalculusofvariations,energyanalysismethod,commutativityoftheproductsofdifferenceoperators,decompositionofhigh-orderdifferenceoperatorsandthetheoryofaprioriestimatesareintroducedandanoptimalordererrorestimatesinl~2normisderived.Thismethodhasbeenappliedsuccessfullytothenumericalsimulationofenhancedoilproductioninactualoilfields,andthesimulationresultsarequiteinterestingandsatisfactory.