简介：氧化物PbMn(SO4)的磁性2由通过SO4tetrahedra与对方一起连接了的MnO6octahedra组成了，很好在实验被学习。在这篇论文，我们探索了它的有趣电子并且有第一原则的计算的磁性。也就是，我们Mn离子高有的所有旋转的结果表演说S=5/2，并且在NN和NNN之间的磁性的couplings是antiferromagnetic，它与试验性的结果同意很好。而且，吃惊在NN和NNN之间的相互作用最优地与扩大H被解释的旋转交换结果

简介：Weperformfirst-principlecalculationsforthestudyoftheorthorhombicRb2Cd2(SO4)3structure.Electronicenergybands,totalandpartialdensitiesofstatesarereportedandanalysed.Itisfoundthatoxygenatomic2pelectronsstronglyhybridizewithRb/orCd4dandS2pstates,resultingintwo-typeionicgroupswithweakcouplings.Itisshownthatmacroscopicdomainwallsoriginatefromsuchweak-couplingionicgroups,arisingatthecellboundaries.Theasymmetriccationbonds(Rb-OandCd-O)andthesubsequentrotationsoftheS04tetrahedracanleadtothedrivingforceoftheferroelectricbehaviour.Thepredictedpyroelectriccurrenteffectsareobservedexperimentallyintheferroelectricphase.

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简介：Theoccurrencemodesofalkaliandalkaline-earthmetals(AAEMs)incoalrelatetotheirreleasebehaviorandashformationduringcombustion.TobetterunderstandthetransformationofAAEMs,thereleasebehaviorofwater-soluble,HCl-soluble,HCl-insolubleAAEMsduringShenmucoal(SMcoal)oxy-fuelcombustioninthepresenceofSO2andH2Oinadrop-tubereactorwasinvestigatedthroughserialdissolutionusingH2OandHClsolutions.TheresultsshowthatthereleaseratesofAAEMsincreasewithanincreaseintemperatureunderthethreeatmospheresstudied.ThehighreleaseratesofMgandCafromSMcoalaredependentonthehighcontentofsolubleMgandCainSMcoal.SO2inhibitsthereleaseratesofAAEMs,whileH2Opromotesthem.TheeffectsofSO2andH2OontheNaandKspeciesaremoreevidentthanthoseonMgandCaspecies.AllthreetypesofAAEMsincoalcanvolatilizeinthegasphaseduringcoalcombustion.TheW-typeAAEMsreleaseexcessively,whereasthereleaseratesofI-typeAAEMsarerelativelylower.DifferenttypesofAAEMmayinterconvertthroughdifferentpathwaysundercertainconditions.BothSO2andH2Opromotethetransformationreactions.TheeffectofSO2wasrelatedtosulfateformationandthepromotionbyH2OoccursbecauseofadecreaseinthemeltingpointofthesolidaswellasthereactionofH2O.

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简介：One-potachievementofethyllevulinatefromcassavawasconductedinethanol-watersystemoverseveralsimplesulfatesaltcatalysts.Al2（SO4）3catalysthadthebestperformanceinsynthesizingethyllevulinatecomparingwiththoseofaseriesofsulfatesalts.Thehighestyieldsofethyllevulinatewasupto39.27%aswellas7.78%levulinateacidwhencassavawascatalyzedinethanolmediumbyadding10wt%water.13Cand1HNMRspectroscopicinvestigationsconfirmedthatisomerizationofglucosetofructoseoverAl2（SO4）3catalystisanimportantstepinproducingethyllevulinateandlevulinateacid.DuetoaggregationsofAl3+underhydrothermalconditions,tinyamountofAl3+weredetectedinfiltrateatthepercentageof0.32%evenifinabsolutewater.BronstedandLewisacidscouldimprovetheyieldofethyllevulinateandlevulinateacidbysynergisticeffect.AllresultssuggestedthatA12（SO4）3wasasimpleandefficientcatalystforethyllevulinateandlevulinateacidproduction.

简介：TheeffectsofSO2,SO3ondenovosynthesisofpolychlorinateddibenzo-p-dioxins(PCDDs)anddibenzofurans(PCDFs)werestudiedusingmodelflyashesincorporatingcopperoxideandactivatedcarbon.ItwasfoundthattheinhibitiveeffectofSO2onPCDD/FsformationissimilartothatofSO3.Toinvestigatetheinhibitionmechanism,CuSO4formationsfrombothCuOandCuCl2wereexamined.TheabilityofSO3toconvertCuCl2andCuOonasilicasupportintosulfateismuchstrongerthanthatofSO2.However,replacingsilicabyactivatedcarbonleadstoamuchhighconversionofCuCl2toCuSO4inthepresenceofSO2.ThepromotionbyactivatedcarbonisexplainedbythereductionofCuCl2toCu2Cl2andtheeventualconversionofCu2Cl2intoCuSO4isthemaininhibitionmechanismofSO2ondenovosynthesisofPCDD/Fs.

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简介：选用aug-cc-pVTZ及aug-cc-pVQZ基组对不同H2-H2位形进行了量子化学计算,外推出了氢分子间各向异性ab-initio作用势。依据实验数据确定出氢分子相互作用的5-体模型,在全局最优算法基础上拟合出了包含电四极矩项、多体极化作用项及三体关联项等在内的氢分子间各向异性作用势。结果验证了拟合势与ab-initio势能曲线几乎重合,两者偏差落在（-1.35K,1.29K）范围内;得出的氢分子第二维里系数与实验结果一致。

简介：APt-MoO3/Ccatalyst,aimedtoeliminatetheharmfuleffectofsulfurdioxide（SCb）ontheperformanceofPtnanoparticles（NPs）forcatalysisofoxygenreductionreaction（ORR）inprotonexchangemembranefuelcells（PEMFC）,isdevelopedandcharacterizedbyTEM,XRDandXPS.TheresultsrevealthatPt-MoO3/Ccatalystexhibitsnotonlyahighercatalyticactivity,butalsoabetterSO2poisoningresistanceandabetterrecoveryperformancethanthecommercialPt/Ccatalystdoes.

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简介：Thispaperreportsthattheetchingmorphologyofdislocationsin8°off-axis4H-SiCepilayerisobservedbyusingascanningelectronicmicroscope.Itisfoundthatdifferenttypesofdislocationscorrespondwithdifferentdensitiesandbasalplanedislcation(BPD)arrayandthreadingedgedislocation(TED)pileupgroupliealongsomecertaincrystaldirectionsintheepilayer.Itisconcludedthattheelasticenergyofthreadingscrewdislocations(TSDs)ishighestandTEDsislowestamongthesedislocations,sothedensityofTSDsislowerthanTEDs.TheBPDscanconverttoTEDsbutTSDscanonlypropagateintotheepilyerinspiteofthehigherelasticenergythanTEDs.ThereasonoftheformofBPDsarrayinepilayeristhatthebigstepalongthebasalplanecausedbyfacedefectsblockedtheupstreamatoms,andTEDspileupgroupisthatthedislocationsslideisblockedbydislocationgroupsinepilayer.

简介：与飘移散开(DD)的联合使用模型，试验性的测量参数和小信号的正弦曲线不变的分析，我们为4H-SiC提取Y参数埋葬隧道的金属氧化物半导体域效果晶体管(BCMOSFET)。输出电线走火水流获得G，梅森的不变的U分别地在普通来源的配置f(T)和摆动f(最大)的最大的频率为外推的统一水流获得频率被计算。这里f(T)=800MHz和f(最大)=5GHz为4H-SiCBCMOSFET被提取，当地效果活动性到达它的山峰时，珍视87cm(2)/Vs什么时候V-GS=4.5V。模拟结果清楚地证明4H-SiCBCMOSFET和地效果活动性的典型频率是优异的，由于新奇结构，与常规MOSFET相比。

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简介：Takingadvantageofthelargeγ-detectorarrayGammasphereandtherecoilmassseparatorFMA,highspinstatesin117Bawereinvestigatedthroughtherecoil-β-delayedprotondecaytaggingtechniqueviatheheavy-ioninducedfusion-evaporationreaction64Zn(58Ni,2p3n)117Ba,atabeamenergyof305MeV.Promptγraysbelongingto117Bahavebeenidentifiedfurthermore,arotationalbandhasbeenidentifiedforthefirsttimeandpresentedasbandAinFig.1.

简介：Twofamiliesofcatalysts,basedonPdnanoparticlessupportedonceramicasymmetrictubularaluminamembranes,arestudiesinthedirectsynthesisofH_2O_2.TheyarepreparedbydepositingPdintwoways:(i)reductionwithN_2H_4inanultrasonicbathand(ii)byimpregnation-deposition.Thefirstpreparationleadstolargerparticles,withaveragesizeofaround11nm,whilethesecondpreparationleadstosmallerparticles,withaveragesizearound4nm.Thecatalyticmembranesweretestedasprepared,afterthermaltreatmentinairandafterfurtherpre-reductionwithH_2inmild(100℃)conditions.SampleswerecharacterizedbyTEM,CO-chemisorptionmonitoredbyDRIFTSmethodandTPR,whilecatalytictestshavebeenperformedinasemi-batchrecirculationmembranereactor.Experimentalcatalyticresultswereanalysedusingtwokineticsmodelstoderivethereactionconstantsfortheparallelandconsecutivereactionsofthekineticnetwork.SmallerparticlesofPdshowlowerselectivityduetothehigherrateofparallelcombustion,evenifthebetterdispersionofPdandthushighermetalsurfaceareainthesampleleadtoaproductivityinH_2O_2similarorevenhigherthanthesamplewiththelargerPdparticles.IndependentlyonthepresenceofsmallerorlargerPdnanoparticles,anoxidationtreatmentleadstoasignificantenhancementintheproductivity,althoughthecatalystprogressivelyreducesduringthecatalyticprocess.Theinhibitionoftheparallelcombustionreaction(towater)inducedfromthecalcinationtreatmentremainsafterthein-situreductionoftheoxidizedPdspeciesformedduringthepre-treatment.Thisislikelyduetotheeliminationofdefectsiteswhichdissociativelyactivateoxygen,andtentativelyattributedtoPdsitesabletogivethree-andfour-foldcoordinationofCO.

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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：Theroleofpulseparametersonnanoparticlepropertyisinvestigatedself-consistentlybasedonacoupleoffluidmodelandaerosoldynamicsmodelinacapacitivelycoupledparallel-plateacetylene(C2H2)discharge.Inthismodel,themasscontinuityequation,momentumbalanceequation,andenergybalanceequationforneutralgasaretakenintoaccount.Thus,thethermophoreticforceariseswhenagastemperaturegradientexists.Thetypicalresultsofthismodelarepositiveandnegativeiondensities,electronimpactcollisionsrates,nanoparticledensity,andchargedistributions.Thesimulationisperformedfordutyratio0.4/0.7/1.0,aswellaspulsemodulationfrequencyfrom40kHzto2.7MHzforpureC2H2dischargesatapressureof500mTorr.Wefindthatthepulseparameters,especiallythedutyratio,haveagreataffectonthedissociativeattachmentcoefficientandthenegativedensity.Moreimportantly,bydecreasingthedutyratio,nanoparticlesstarttodiffusetothewall.Undertheactionofgasflow,nanoparticledensitypeakiscreatedinfrontofthepulseelectrode,wherethegastemperatureissmaller.