简介：研究了不同风速下激光辐照C/C复合材料的氧化速率,利用温度场计算结果,结合氧气在空气中的传质速率,计算了激光辐照下C/C复合材料氧化放热.结果表明,在亚音速的风速下,氧化对C/C复合材料烧蚀的贡献很小,因此,作为激光防护材料,可以忽略C/C复合材料在激光辐照期间的氧化烧蚀.

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简介：Cu-Fecompositeoxideswerepreparedbyco-precipitationmethodandtestedforhigheralcoholsynthesisfromsyngas.TheselectivitytoC2+OHandC6+OHinalcoholdistributionwasveryhighwhilethemethaneproductfractioninhydrocarbondistributionwasratherlow,demonstratingapromisingpotentialinhigheralcoholssynthesisfromsyngas.ThedistributionofalcoholsandhydrocarbonsapproximatelyobeyedAnderson-Schulz-Florydistributionwithsimilarchaingrowthprobability,indicatingalcoholsandhydrocarbonsderivedfromthesameintermediates.TheeffectsofCu/Femolarratio,reactiontemperatureandgashourlyspacevelocity(GHSV)oncatalyticperformancewerestudiedindetail.ThesamplewithaCu/Femolarratioof10/1exhibitedthebestcatalyticperformance.Higherreactiontemperatureacceleratedwater-gas-shiftreactionandledtolowertotalalcoholsselectivity.GHSVshowedgreateffectoncatalyticperformanceandhigherGHSVincreasedthetotalalcoholselectivity,indicatingthereexistedvisibledehydrationreactionofalcoholintohydrocarbon.

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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.

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.

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.

简介：Directconversionoffructose-basedcarbohydratesto5-ethoxymethylfurfural(EMF)catalyzedbyLewisacidinethanolwasinvestigated.ItwasfoundthatBF3(Et)2Owasfavorablefor5-hydroxymethylfurfural(HMF)etherificationtoEMF.BF3(Et)2OcombinationwithAlCl36H2Owiththemolarratioof1wasaneffectivecatalystsystemforsynthesisofEMFfromfructose-basedcarbohydrates.55.0%,45.4%and23.9%ofEMFyieldswereobtainedfromfructose,inulinandsucroseunderoptimizedconditions,respectively.

简介：Throughournewly-developed'chemicalvapordepositionintegratedprocess(CVD-IP)'usingcarbondioxide(CO2)astherawmaterialandonlycarbonsourceintroduced,CO2couldbecatalyticallyactivatedandconvertedtoanewsolid-formproduct,i.e.,carbonnanotubes(CO2-derived)ataquitehighyield(thesingle-passcarbonyieldinthesolid-formcarbon-productproducedfromCO2catalyticcaptureandconversionwasmorethan30%atasingle-passcarbon-base).Forcomparison,whenonlypurecarbondioxidewasintroducedusingtheconventionalCVDmethodwithoutintegratedprocess,nosolid-formcarbon-materialproductcouldbeformed.IntheadditionofsaturatedsteamatroomtemperatureinthefeedforCVD,thereweremuchmoreend-openingcarbonnano-tubesproduced,ataslightlyhighercarbonyield.Theseinspiringworksopenedaremarkableandalternativenewapproachforcarbondioxidecatalyticcapturetosolid-formproduct,comparingwiththatofCO2sequestration(CCS)orCO2mineralization(solidification),etc.Asaresult,therewasmuchlessbodyvolumeandalmostnogreenhouseeffectforthissolid-formcarbon-materialthanthoseofprimitivecarbondioxide.