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.

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简介：ThespectrumoftheΣ(1193)excitedstates,Σ,withisospinI=1andstrangenessS=??1isoneofthemostimportantissuesinhadronicphysics.TheΣresonancesaremostlyproducedandstudiedinK-inducedreactions.ManyΣresonancesarenowcatalogedbytheParticleDataGroup[1].However,ourknowledgeoftheseresonancesisstillverypoor.Intheenergyregionbelow2GeV,onlyafewofthemarewellestablished,suchastheΣ(1385)ofspin-parityJP=3=2+,Σ(1670)ofJp=3=2??andΣ(1775)ofJp=5=2??.Theothersarenotwellestablishedandsomeofthemareevenoflargeuncertaintiesontheirexistence.Thus,thestudyoftheΣresonancewiththeavailableexperimentaldataisnecessary.

简介：研究目的：研究新型磁性回热填料Gd2O2S对液氦温区高频脉管制冷机多级回热器损失特性的影响。创新要点：确定了不同回热填料以及运行参数（频率、平均压力）下液氦温区多级脉管制冷机的制冷温度和各级预冷量，进一步明确了4K高频回热损失机理。研究方法：采用理论研究与实验验证相结合的方法，基于一台两级G-M型低频脉管制冷机预冷的单极斯特林型高频脉管制冷机，研究多级回热器在高频以及4K温区下的损失特性。选取新型回热填料Gd2O2S替代部分回热填料HoCu2，比较回热器采用两种填料时在不吲运行频率及平均压力下的冷端制冷温度（图10）、各级预冷量和预冷温度（图1112）。重要结论：采用孔隙率较小的新型磁性回热填料Gd2O2S可显著改善第一级回热器内压力波与质量流的相位关系，从而减小该级回热损失。减小平均压力可以降低制冷机无负荷制冷温度并减小第二级预冷量，但制冷工质氦的体积比热容会急剧增大，从而使低温级回热器的换热对频率非常敏感。此外，频率对高温级回热器的回热特性影响不明显。该方法可以为三级斯特林型4K多级脉管制冷机提供设计依据。

简介：本文首先介绍了印制电路板及其课程的培养目标,其次介绍了采用项目教学法的教学步骤,并以＂＋5V直流稳压电源电路设计与制作＂为例,阐述了采用项目教学法的教学过程,并与传统教学法的教学效果进行对比,最后介绍了使用项目教学法时的注意事项。

简介：电位差计常用于精确测量电动势、电压、电流、电阻等电学量，在实验室可用来校准电表。文章对实验室经常、频繁使用的电流表采用UJ31型电位差计配用不同的平衡指示器进行校准，对所测数据进行分析对比，得出被校表的准确度等级及采用不同平衡指示器时的测量结果。

简介：AnovelSr2CuInO3Soxysulfidep-typesemiconductorphotocatalysthasbeenpreparedbysolidstatereactionmethodanditexhibitsintriguingvisiblelightabsorptionpropertieswithabandgapof2.3eV.Thep-typesemiconductorcharacterofthesynthesizedSr2CuInO3SwasconfirmedbyHallefficientmeasurementandMott-Schottkyplotanalysis.First-principlesdensityfunctionaltheorycalculations(DFT)andelectrochemicalmeasurementswereperformedtoelucidatetheelectronicstructureandtheenergybandlocations.Itwasfoundthattheas-synthesizedSr2CuInO3Sphotocatalysthasappreciateconductionandvalencebandpositionsforhydrogenandoxygenevolution,respectively.Photocatalytichydrogenproductionexperimentsunderavisiblelightirradiation(λ>420nm)werecarriedoutbyloadingdifferentmetalandmetal-likecocatalystsonSr2CuInO3SandRhwasfoundtobethebestoneamongthetestedones.

简介：Inthefarfieldoftheintensitydistributionofthebeamdeliveredbyatwo-stagetransient–collisionalexcitationX-raylaser(XRL),anon-expectedinterferencepatternthatisstablefromshottoshothasbeendiscovered.Itisdemonstratedthattheinterferenceiscausedbytheemergenceofanimaginarysourceintheamplifyingplasma,whichisphasematchedtotheradiationofthegenerator.TheobservedphenomenoniscalledanX-raycoherentmirage.Toexplaintheobtainedresults,anewtheoreticalapproachisdeveloped.ThebasicessentialconditionsforformationoftheX-raymirageareformulated,andpossibleapplicationsarediscussed.Thispaperdetailstheexperiments,includingtheformulationofthenecessaryandsufficientconditionsforformationoftheX-raymirage,andpossibleapplicationsarediscussed.

简介：立足实用化脉冲星导航技术需要，梳理了现有脉冲星导航探测方法及研究进展，结合探测器运行空间环境，分析了探测器指标，比较了现有天基x射线探测方法、载荷特点以及各探测技术存在的不足，并对空间辐射环境去噪方法进行了评述，对后续脉冲星导航探测方法构建及装置研制提出了几点建议。

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简介：本文采用Matlab软件中的Simulink提供的模块来实现物理实验数据处理的可视化,并用金属丝杨氏模量的测量实验数据展示了数据处理可视化过程。可视化数据处理扩大了常规教学和训练方法,对传统的教学形式进行了补充。

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简介：Thespectrumofisospin3/2Δ++(1232)excitedstatesisoneofthemostimportantissuesinhadronicphysicsandisattractingmuchattentionbecauseitisthemostexperimentallyaccessiblesystemcomposedofthreeidenticalvalencequarks.However,ourknowledgeontheseresonancesmainlycomesfromoldNexperimentsandisstillverypoor[1].Intheenergyregionaroundorabove2.0GeV,therearestillmanytheoreticalpredictionsofmissingΔstateswhichhavesofarnotbeenobserved.Searchingforthesemissingstatesfromotherproductionprocessesisnecessary.ApossiblenewexcellentsourceforstudyingtheseΔresonancecomprisesthe+p!K+Σ+(1385)andpp!nK+Σ+(1385)reactions,whichhaveaspecialadvantage,i:e:,thereisnocontributionsfromisospin1/2nucleonresonancesduetotheisospinandchargeconservations.

简介：InthispaperweusedMOF-5andCu3(BTC)2toseparateCO2/CH4andCH4/N2mixturesunderdynamicconditions.Bothmaterialsweresynthesizedandpelletized,thusallowingforameaningfulcharacterizationinviewofprocessscale-up.ThematerialswerecharacterizedbyX-raydiffraction(XRD)andscanningelectronmicroscopy(SEM).Byperformingbreakthroughexperiments,wefoundthatCu3(BTC)2separatedCO2/CH4slightlybetterthanMOF-5.BecausethecrystalstructureofCu3(BTC)2includesunsaturatedaccessiblemetalsitesformedviadehydration,itpredominantlyinteractedwithCO2moleculesandmoreeasilycapturedthem.Conversely,MOF-5withasuitableporesizeseparatedCH4/N2moreefficientlyinourbreakthroughtest.

简介：Veryrecently,BelleannouncedtheirobservationofΥ(5S)!bJ!(J=0;1;2),indicatingthattheΥ(5S)!bJ!decaysalsohavelargedecaywidths,i.e.,themeasuredbranchratiosofΥ(5S)!bJ!are<3:410??3,(1:640:23+0:30??0:22)10??3,and(0:570:220:07)10??3withJ=0;1;2,respectively[1].ItshouldbenoticedthateventhoughthetreelevelcontributionstoΥ(5S)!bJ!(J=0;1;2)shouldbestronglysuppressedduetotheOkubo-Zweig-Iizuka(OZI)rule,suchlargedecaywidthsareobserved,whichagaininspiresourinterestinunderstandingsuchquantities.Inthiswork,weproposethatthecontributionfromthehadronicloopshouldbeconsideredinstudyingΥ(5S)!bJ!.

简介：ThreeseriesofCeO2/CuOsampleswerepreparedbyimpregnationmethodandcharacterizedbyXRD,N2adsorption-desorption,temperatureprogrammedreduction(TPR),XPSandTEMtechniques.IncomparisonwiththesamplespreparedwithCuOasinitialsupport,thesampleswithCu(OH)2asinitialsupporthavehigherreducibilitiesandsmallerrelativeTPRpeakareas,andalsolargerspecificsurfaceareasatcalcinationtemperaturesof400℃–600℃.Asaresult,Cu(OH)2isbetterthanCuOasinitialsupportforpreferentialoxidationofCOinexcessH2(CO-PROX).Thebestcatalyticperformancewasachievedonthesamplecalcinedat600℃andwithanatomicratioofCe/Cuat40%.XPSanalysesindicatethatmoreinterfacelinkagesCe-O-Cucouldbeformedwhenitwascalcinedat600℃.AndtheatomicratioofCe/Cuat40%ledtoaproperreducibilityforthesampleasillustratedbytheTPRmeasurements.

简介：AnewSnO_2-Fe_2O_3/SWCNTs(single-walledcarbonnanotubes)ternarynanocompositewasfirstsynthesizedbyafacilehydrothermalapproach.SnO_2andFe_2O_3nanoparticles(NPs)werehomogeneouslylocatedonthesurfaceofSWCNTs,asconfirmedbyX-raydiffraction(XRD),transmissionelectronmicroscope(TEM)andenergydispersiveX-rayspectroscopy(EDX).Duetothesynergisticeffectofdifferentcomponents,theassynthesizedSnO_2-Fe_2O_3/SWCNTscompositeasananodematerialforlithium-ionbatteriesexhibitedexcellentelectrochemicalperformancewithahighcapacityof692mAh·g~(-1)whichcouldbemaintainedafter50cyclesat200mA·g~(-1).Evenatahighrateof2000mA·g~(-1),thecapacitywasstillremainedat656mAh·g~(-1).

简介：Thereisagrowingsupportforthelowlyingscalarmesonsf0(500),f0(980),a0(980),and(800)tobegenerateddynamicallyfromtheinteractionofpseudoscalarmesons,whilethecaseofthenextsetofscalarresonancesathigherenergies,f0(1370),f0(1710),K0(1430)ismoreaquestionofdebate.Soisthecaseofthetensorresonancesf2(1270),f′2(1525),K2(1430).AnewperspectiveonthesestateshasbeenofferedinRef.[1]wherethef0(1370)andf2(1270)resonancesareshowntobegeneratedfromtheinteractionprovidedbythelocalhiddengaugeLagrangiansimplementingunitarization.Itisshownthattheideaofthenatureofthesestatesasvectormeson-vectormesoncompositestateshasbeentestedinmanyreactions.Yet,thepermanentdiscussionoftheissuedemandsextrachecksforotherobservablesand,inthissense,theweakdecaysbringanewsourceofvaluableinformationthatshouldservetotestdifferentmodels.

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