简介：Theoreticalmodelsofstellarevolutionpredictnegligiblequantitiesof6Li,9Be,and11Binthehydrogenburningphasesofastar’sevolution[1].TheprimordialBig-Bangnucleosynthesis(BBN)modelmightbemoregenerousinitsproductionoftheseelements[2].Theradiative-capturecrosssectionforprotoncaptureon11Bleadingto12CissmallatastrophysicallyinterestingenergiesbecauseofthelargeCoulombbarrier.

简介：Two-dimensional（2D）graphitecarbonnitride（g-C3N4）nanosheetshavebeensuccessfullyusedasasaturableabsorber（SA）inapassivelyQ-switchedNd:LLFlaserat1.3μmforthefirsttime,tothebestofourknowledge.Underanincidentpumppowerof9.97W,theshortestpulsedurationof275nswasacquiredwithoutputpowerof0.96Wandpulserepetitionrateof154kHz,resultinginapulseenergyof6.2μJ.Inaddition,thesaturableabsorptionbehaviorsofzero-dimensional12nmg-C3N4nanoparticles（g-C3N4-NPs）andthree-dimensionalorderedmesoporousg-C3N4（mpg-C3N4）werealsoobserved,althoughtheirmorphologyandstructurewerequitedifferentfrom2Dg-C3N4.Theexperimentalresultsintroducethepotentialapplicationofg-C3N4nanomaterialsasSAsinQ-switchedlasers.

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简介：Catalyticpropertiesofthemetal-organicframeworkCr-MIL-101insolvent-freecycloadditionofCO2toepoxidestoproducecycliccarbonatesusingtetrabutylammoniumbromideasco-catalysthavebeenexploredundermildreactionconditions(8barCO2,25C).Styreneandpropylenecarbonateswereformedwithhighyields(95%and82%,respectively).CatalyticperformanceofCr-MIL-101wascomparedwithotherMOFs:Fe-MIL-101,Zn-MOF-5andHKUST-1.Thecatalyticpropertiesofdifferentquaternaryammoniumbromides,Cr-MIL-101aswellasPW12/Cr-MIL-101compositematerialhavebeenassessedinoxidativecarboxylationofstyreneinthepresenceofbothtert-butylhydroperoxideandH2O2asoxidantsat8100barCO2and2580Cwithselectivitytostyrenecarbonateupto44%at57%substrateconversion.

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简介：WereportonN-dopedp-typeZnOfilmswiththec-axisparalleltothesubstrate.ZnOfilmswerepreparedonana-Al2O3(0001)substratebysolid-sourcechemicalvapourdeposition(CVD),Zn(CH3COO)2.2H2OwasusedastheprecursorandCH3COONH4asthenitrogensource.Thegrowthtemperaturewasvariedfrom300℃to600℃,theas-grownZnOfilmdepositedat500℃showedp-typeconductionwithitsresistivityof42Ωcm,carrierdensity3.7×10^17cm^-3andHallmobility1.26cm^2V^-1.s^-1atroomtemperature,whicharethebestpropertiesforp-typeZnOdepositedbyCVD.Thep-typeZnOfilmpossessesatransmittanceofabout85%inthevisibleregionandabandgapof3.21eVatroomtemperature.

简介：Pt/WO3/CnanocompositeswithparallelWO3nanorodsweresynthesizedandappliedasthecathodecatalystforprotonexchangemembranefuelcells(PEMFCs).Electrochemicalresultsandsinglecelltestsshowthatanenhancedactivityfortheoxygenreductionreaction(ORR)isobtainedforthePt/WO3/CcatalystcomparedwithPt/C.ThehighercatalyticactivitymightbeascribedtotheimprovedPtdispersionwithsmallerparticlesizes.ThePt/WO3/Ccatalystalsoexhibitsagoodelectrochemicalstabilityunderpotentialcycling.Thus,thePt/WO3/CcatalystcanbeusedasapotentialPEMFCcathodecatalyst.

简介：ThisstudyshowsthepreparationofaTiO_2coatedPt/C(TiO_2/Pt/C)byatomiclayerdeposition(ALD),andtheexaminationofthepossibilityforTiO_2/Pt/Ctobeusedasadurablecathodecatalystinpolymerelectrolytefuelcells(PEFCs).CyclicvoltammetryresultsrevealedthatTiO_2/Pt/Ccatalystwhichhas2nmprotectivelayershowedsimilaractivityfortheoxygenreductionreactioncomparedtoPt/Ccatalystsandtheyalsohadgooddurability.TiO_2/Pt/Cpreparedby10ALDcyclesdegraded70%after2000Accelerateddegradationtest,whilePt/Ccorroded92%inthesameconditions.TiO_2ultrathinlayerbyALDisabletoachieveagoodbalancebetweenthedurabilityandactivity,leadingtoTiO_2/Pt/CasapromisingcathodecatalystforPEFCs.ThemechanismoftheTiO_2protectivelayerusedtopreventthedegradationofPt/Cisdiscussed.

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简介：Radiotherapyisacommontreatmentmodalityforheadandneckcancers,nasopharyngealcancers,primarybraintumorsandbrainmetastases.Alargenumberofpatientsintheworldwithprimaryormetastaticbraintumorswillrequirelargevolumeorwholebrainirradiationeveryyear.However,therapeuticirradiationnotonlykillstumorcells,butalsoinjuresnormalbraintissue,whichiscommonlyassociatedwithsignificantfunctionalmorbidityanddecreasedqualityoflifeinpatientstreatedwithbrainradiotherapy[1].

简介：在“强光一号”加速器上,对LM7805型电源芯片和EE80C196KC20型单片机进行了脉冲γ辐照效应实验研究,获得了单片机的闩锁阈值,并得到了单片机和电源芯片的扰动时间随剂量率的变化规律,从实验上证实了电源芯片对单片机脉冲γ辐照闩锁效应的抑制作用.

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简介：MesoporousLiFePO4/Ccompositescontaining80wt%ofhighlydispersedLiFePO4nanoparticles(4-6nm)werefabricatedusingbimodalmesoporouscarbon(BMC)ascontinuousconductivenetworks.TheuniqueporestructureofBMCnotonlypromisesgoodparticleconnectivityforLiFePO4,butalsoactsasarigidnano-confinementsupportthatcontrolstheparticlesize.Furthermore,thecapacitieswereinvestigatedrespectivelybasedontheweightofLiFePO4andthewholecomposite.Whencalculatedbasedontheweightofthewholecomposite,itis120mAh·g-1at0.1Cofthehighloadingelectrodeand42mAh·g-1at10Cofthelowloadingelectrode.TheelectrochemicalperformanceshowsthathighLiFePO4loadingbenefitslargetapdensityandcontributestotheenergystorageatlowrates,whiletheelectrodewithlowcontentofLiFePO4displayssuperiorhighrateperformance,whichcanmainlybeduetothesmallparticlesize,gooddispersionandhighutilizationoftheactivematerial,thusleadingtoafastionandelectrondiffusion.

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