简介：硅橡胶海绵的制备主要有化学发泡成型和物理成孔剂成型两种方法，但采用物理成孔剂成型后必须除去橡胶中包含的成孔剂以制得海绵材料。成孔剂可分为易溶性无机盐以及尿素等小分子易溶有机物，采用水浸泡的方式可以将成孔剂溶析出来得到泡孔。一般来说为缩短工艺时间，简化工艺流程，可采取提高水温、加快换水频率以加快成孔剂溶析速度。

简介：Theground-stateandthermodynamicpropertiesofquantummixed-spinchainsof1/2-1/2-1-1and3/2-3/2-1-1areinvestigatedbyaquantumMonteCarlosimulationwiththeloop-clusteralgorithm.For1/2-1/2-1-1chain,wefindithastwophasesseparatedbyanenergy-gapvanishingpointintheground-state.For3/2-3/2-1-1chain,thenumericalresultsshowtwoenergy-gapvanishingpointsisolatedbydifferentphasesinitsground-state.Ourcalculationsindicatethatallthesegroundstatephasescanbeunderstoodbymeansofvalence-bond-solidpicture,andthethermodynamicbehavioratfinitetemperaturesiscontinuousasafunctionofparameterα=J2/J1.

简介：综述了用于整体煤气化联合循环发电（ＩＧＣＣ）技术中的高温煤气脱硫剂的研究和开发，对几类主要应用的脱硫剂的优缺点进行了比较总结，指出了脱硫剂在工业应用中最重用的几个特性，并对今后脱硫剂的改进方向提出了建议。更多还原

简介：1．河水总是向低处流，抛出的物体总会落向地面，这些现象说明，地球上的物体总是要受到________力的作用，该力的施力物体是______。

简介：首次在温和条件下，用在传统微孔沸石合成中常作为导向剂的乙二胺或1，6-己二胺替代NaOH作催化剂合成出SiO2基中孔MCM-41分子筛。合成样品用XRD和N2吸附等温线进行表征。实验结果表明，由于这种替代，使相应合成样品及焙烧样品的中孔骨架结构的有序度明显提高。在XRD图中四个衍射峰清晰可辨，是典型的六方紧密堆积，晶胞参数a0分别为4.11nm和3.75nm，且d100值随所用胺分子中碳链的增长逐渐从3．56nm减少到3．24nm，同时产物孔径由中孔转变为微孔。更多还原

简介：In2014,theresearchersofTheoreticalPhysicsGroupatIMPhavecarriedouttheirresearchworkonnuclearphysics,heavyionphysicsandhadronphysics.Someimportantresultshavebeenobtained.Thethree-bodyforce(TBF)effectontheoff-shellbehavioroftheneutronandprotonmassoperatorsinasymmetricuclearmatterhasbeeninvestigatedwithintheframeworkoftheextendedBrueckner-Hartree-Fockapproach[1].Athighdensitieswellabovethenormalnuclearmatterdensity,theTBFisshowntoaffectsignificantlytheoff-shellehaviorofboththeprotonandneutronmassoperators.Thedensitydependenceofsymmetryenergyaroundtheuclearsaturationdensityhasbeenstudied[2].Anewapproachhasbeenproposedandappliedtodeterminetheymmetryenergycoefficientofheavynucleibasedontheavailableexperimentalnuclearmassesofheavynuclei.Theobtainedresultisadoptedtoanalyzethedensitydependenceofsymmetryenergyofnuclearmatteraroundtheaturationdensity.TheslopeparameteratthesaturationdensityisdeterminedtobeL=(50.515.5)MeV.

简介：在生物教学中，教师针对课程创设出相应的教学情境，并用各种方法让学生的思维逐渐进入情境，为完成课时目标创造条件。

简介：课堂教学中,教师在适当的时机用多种提问方法提高教学技巧.本文阐述提问时机、方法和技巧.

简介：In2010,theBESCollaboration[1]foundaclearenhancementintheK0K0massdistributionintheJ=ψ!ηK0K0decay.SuchanenhancementisusuallyasignatureofanL=0resonancearoundthreshold,whichinthiscasewouldcorrespondstoanh1statewithquantumnumbersIG(JPC)=0??(1+??).Thish1statewaspredictedbytheChiralUnitarytheoryintheKKinteraction.Becauseoftheconversationlaw,thisstatecanonlydecaytoK0K0channel,andcanbestudiedefficientlyintheJ=ψ!ηK0K0decay.

简介：Tostudytheelectromagnetic(EM)backscattercharacteristicsoffreakwavesatmoderateincidenceangles,weestablishanEMbackscatteringmodelforfreakwavesin(1+1)-dimensionaldeepwater.ThenonlinearinteractionbetweenfreakwavesandBraggshortwavesisconsideredtobethebasichydrodynamicspectramodulationmechanisminthemodel.NumericalresultssuggestthattheEMbackscatteringintensitiesoffreakwavesarelessthanthosefromthebackgroundseasurfaceatmoderateincidenceangles.Thenormalisedradarcrosssections(NRCSs)fromfreakwavesarehighlypolarisationdependent,evenatlowincidenceangles,whichisdifferentfromthesituationfornormalseawaves;moreover,theNRCSoffreakwavesismorepolarisationdependentthanthebackgroundseasurface.NRCSdiscrepanciesbetweenfreakwavesandthebackgroundseasurfacewithusinghorizontaltransmittinghorizomtal(HH)polarisationarelargerthanthoseusingverticaltransmittingvertical(VV)polarisation,atmoderateincidentangles.NRCSdiscrepanciesbetweenfreakwavesandbackgroundseasurfacedecreaseswiththeincreaseofincidenceangle,inbothHHandVVpolarisationradars.Asanapplication,inthesynthetic-apertureradar(SAR)imagingoffreakwaves,wesuggestthatfreakwavesshouldhaveextremelylowbackscatterNRCSsforthefreakwavefacetwiththestrongestslope.Comparedwiththebackgroundseasurface,thefreakwavesshouldbedarkerinHHpolarisationechoimagesthaninVVechoimages,inSARimages.FreakwavescanbemoreeasilydetectedfromthebackgroundseasurfaceinHHpolarisationimagesthaninVVpolarisationimages.Thepossibilityofdetectionoffreakwavesatlowincidenceanglesismuchhigherthanathighincidenceangles.

简介：ThesplittingofpotentialenergylevelsforgroundstateX2ΠgofOx2(x=+1,1)underspin–orbitcoupling(SOC)hasbeencalculatedbyusingthespin–orbit(SO)multi-configurationquasi-degenerateperturbationtheory(SO-MCQDPT).TheirMurrell–Sorbie(M–S)potentialfunctionsaregained,andthenthespectroscopicconstantsforelectronicstates2Π1/2and2Π3/2arederivedfromtheM–Sfunction.TheverticalexcitationenergiesforOx2(x=+1,1)areν[O+12(2Π3/2→X2Π1/2)]=195.652cm1,andν[O12(2Π1/2→X2Π3/2)]=182.568cm1,respectively.Allthespectroscopicdataforelectronicstates2Π1/2and2Π3/2aregivenforthefirsttime.

简介：当堂反馈1．如图所示，锤子对钉子的作用力的施力物体是——，受力物体是——．画出锤子对钉子的作用力的示意图．

简介：1．将手掌压在水平的桌面上，使手掌水平向前运动，会感到手掌受到桌面向__________（选填“前”或“后”）的作用力，此力称为______力．桌面越光滑，手掌受到的力越小，表明____________________________________。

简介：

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：氚作为氢的放射性同位素之一，具有与氢气相同的化学活性和反应性，极易以气态、液态或固态等多种形式扩散到环境中，通过吸入、食入和渗透等不同途径进入人体，从而导致人健康水平下降、各种疾病发生和周边环境质量下降等等。由于氚自身的物理和化学特性，在氚的生产和操作中将产生大量含氚废气，当这些含氚废气的量达到相关排放限值后，就必须进行净化处理。

简介：用常规的浸渍-还原法制备Pt／C催化剂，如果条件控制不好，制备出的Pt粒子大小和分散度不均，且易出现团聚。文中的主要目的是用微波密闭加热的方法，研究制备条件对Pt粒子大小的影响，制备高分散度且Pt粒径大小在一定范围内可控的Pt／C催化剂。

简介：为了深入剖析氢化锂慢化剂正温度效应产生的原因,基于空间核热推进（spacenuclearthermalpropulsion,SNTP）粒子球床堆（particlebedreactor,PBR）的物理模型,使用MCNP程序,从中子热化效应、氢化锂热膨胀效应和极限情况下氢化锂热离解效应3个方面进行慢化剂正温度效应分析。研究表明,在低能区,靶核的热运动、原子之间的化学键及不同中子波之间的干涉效应不能忽略,且随着温度的升高,靶核的激发态更易被激发,此时非弹性散射更易发生、中子更易获得能量,能谱硬化;氢化锂慢化剂正温度效应对PBR堆芯反应性的影响因素中,中子热化效应占主导地位,引入的反应性达到2000pcm,氢化锂热膨胀效应和热离解效应影响较小,引入的反应性分别约为-130pcm和200pcm。

简介：

简介：WeinvestigatethesensitivityoftheangularrotationmeasurementwiththemethodofhomodynedetectioninSU（2）andSU（1,1）interferometersbyemployingorbitalangularmomentum（OAM）.BycombiningacoherentbeamwithavacuumbeaminanSU（2）interferometer,wegetthesensitivityoftheangularrotationmeasurementas1/(2N1/2l).WecansurpassthelimitoftheangularrotationmeasurementinanSU（1,1）interferometerbycombiningacoherentbeamwithavacuumbeamorasqueezedvacuumbeamwhentheprobebeamhasOAM.Withoutinjection,thesensitivitycanreach1/(2N1/2l).Inaddition,byemployinganotherconstructionofanSU（1,1）interferometerwherethepumpbeamhasOAM,withthesameinjectionofanSU（1,1）interferometer,thesensitivityoftheangularrotationmeasurementcanbeimprovedbyafactorof2,reaching1/（4Nl）.Theresultsconfirmthepotentialofthistechnologyforprecisionmeasurementsinangularrotationmeasurements.