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简介：AseriesofdoubleperovskitesRSrMnFeO_6(R=La,Pr,Nd,Sm)wassynthesizedundermildhydrothermalconditions.Crystalgrowthsofthesamplesweresensitivetoalkalinity,temperature,fillingfraction,andcompositionofinitialreactionmixture.ThedesiredseriesofcompoundsbelongstotheclassofAA'BB'O_6perovskiteswitharandomdistributionofMnandFeatomsovertheB-cationsub-lattice.TheirstructuresshowthedistortedorthorhombicsymmetrywithspacegroupPnma.TheshapesandsizesofthecrystalswereanalyzedonaRigakuJSM-6700Fbyscanningelectronmicroscopy.AnalysisdonebyXPS,MssbauerspectroscopyandiodometrictitrationrevealsthatMnandFeionshave+4and+3oxidationstates,respectively.

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简介：Thehydrothermalreactivityofsilicasandwasstudiedusingcementkilndust(CKD)asanactivatorinadditiontothePortlandcementfractionofEl-Karnakcement(ablendofordinaryPortlandcementandgroundsand).AutoclavedEl-Karnakcementpasteswerestudiedatpressuresof0.507,1.013and1.520MPaofsaturatedsteamwithrespecttotheircompressivestrength,kineticsofhydrothermalreactionandthephasecompositionoftheformedhydrates.TheroleofCKDinaffectingthephysicochemicalandmechanicalpropertiesofEl-Karnakcementpasteswasstudiedbyautoclavingofseveralpastescontaining5,7.5,10and20%CKDatapressureof1.013MPaofsaturatedsteam.CKDwasaddedeitherasarawCKD(unwashed)orafterwashingwithwater(washedCKD).TheresultsofthesephysicochemicalstudiesobtainedcouldberelatedasmuchaspossibletotheroleofCKD(raworwashed)inaffectingthehydrothermalreactivityofsilicasandinEl-Karnakcementpastes.

简介：Synthesis,structureandmagneticpropertiesofRudopedperovskitestructuredmanganiteLa0.5Sr0.5MnO3wereinvestigatedexperimentally.Ahydrothermalmethodwasusedforthepreparationofthesamples.Ahigh-temperatureannealingprocesswasalsoemployedtomakeacomparison.AslightlyenhancementoftheunitcellvolumewasobservedwiththeincreaseofRuconcentration.Scanningelectronmicroscopyshowsthatthematerialsaremadeupofcube-shapedparticleswithdimensionofseveralmicrometers.Importantly,itisfoundthatboththeCurietemperatureTCandsaturationmomentcanbereducedbyRudoping.ThevalueofcoercivefieldisnotaffectedbytheintroductionofRu.

简介：TheinfluenceofNa2SO4ontheformationofZnOwhiskerswasinvestigatedinthispaper.ZnOwhiskerswithaspectratiosofupto50weresynthesizedbydissolvingε-Zn（OH）2precursorinNaOH/Na2SO4solutionatroomtemperature,followedbyagingoftheresultingsolutionat140℃for6h.Fouriertransforminfraredspectroscopy,Ramanspectroscopy,andX-rayphotoelectronspectroscopyanalysesrevealedthatSO42-ionswereprimarilyadsorbedonthe（100）planeoftheZnOwhiskersviaanouter-spherecomplexconfiguration（O-H…O）,therebypromotingtheone-dimensionalgrowthofZnOwhiskersalongthec-axis.

简介：FreshZSM-5zeolitecatalystswerepretreatedat460℃and500℃withvariouscumulativeamountofwaterfeed(CAWF)inafixedbedreactor.Thecatalyticprocesswascarriedoutunderthefollowingconditions:atemperatureof480℃;amethanolWHSVof3h-1;amethanolpartialpressureof30kPa;andatimeonstreamof12h,24hand48h,respectively.TheBETparametersofcatalystsanddiffusioncoefficientsoftolueneshowedthatthereweretwotypesofmesoporesgeneratedunderdifferenthydrothermalconditions.MildtemperatureandmoderateCAWFconditionsledtoexternalopenmesoporeswhichcouldbeenteredfromtheexternalsurfaceofthezeolite,whileahightemperatureorahighCAWFconditionresultedinthegenerationofmacroporesorinternalisolatedmesopores,whichwereoccludedinthemicroporousmatrix.TheTGAresultsshowedthatcatalystwithexternalopenmesoporeshadgoodabilitytoresistcokeaccumulationandgoodperformanceonpropyleneselectivity,whiletheinternalisolatedmesoporesdidnocontributetotheincreaseddiffusivityofreactantsandproducts.

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简介：Eu3+/Sm3+codopedBiPO4黄磷与没有表面活化剂的环境经由一个灵巧的热水的方法被综合。X光检查衍射分析证明样品拥有了标准BiPO4单斜晶的结构。扫描电子显微镜学图象证明所有样品与像梭的形状分散得好的、测微计大小的晶体创作了。到Eu3+的从Sm3+的精力转移被光系列和Sm3+4G5/26H5/2排放的腐烂过程证实。橘子红光能在Eu3+/Sm3+codopedBiPO4黄磷被获得。Sm3+4G5/26H5/2排放的平均一生在BiPO4:0.03Sm3+在BiPO4:0.03Sm3+从2.70ms减少了到2.37ms，0.05Eu3+。在395nm附近的强壮、宽的吸收乐队，从Eu3+的7F05L6转变和Sm3+的6H5/24K11/2转变发源，资助BiPO4:Eu3+，有近紫外激动的white-light-emitting二极管的域里的潜在的应用程序的Sm3+黄磷。

简介：ThemesoporousAl-SBA-15zeolitewasobtainedviaimpregnationofpuresilica-basedSBA-15zeolitewithaluminumnitrate.TheAl-SBA-15samplewascalcinedinairat800℃for6handhydrothermallytreatedatnear100℃for120h,respectively,andthenthethermalandhydrothermalstabilityofAl-SBA-15samplewasinvestigatedbyX-raydiffractometry(XRD),scanningelectronmicroscopy(SEM),transmissionelectronmicroscopy(TEM)andnitrogenadsorptionanddesorptiontechniques.TheAl-SBA-15samplewasalsostudiedby27Alnuclearmagneticresonance(27AlNMR)andammoniatemperatureprogrammeddesorption(NH3-TPD)techniques.Inaddition,thecatalyticactivityofAl-SBA-15zeolitewasinvestigatedbytheFriedel-Craftsreactionsof2,4-di-tert-butylphenolwithcinnamylalcohol.ThetestresultsshowedthatthethermalandhydrothermalstabilityofAl-SBA-15zeolitewasbetterthanthatofSBA-15zeo-lite.TheAl-SBA-15zeolitesamplepreparedbyimpregnationmethodexhibitsmoreframeworkaluminumspeciesandAl-O-Siunits.Therefore,thenumberofthesurfacehydroxylgroupswasreduced,resultinginthestabilizationofframeworkstructureofAl-SBA-15zeolite.Thealuminumspeciescanformweakandmedium-strongacidsiteswithcatalyticactivity.

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简介：AfacilehydrothermalmethodwasdevelopedforthepreparationofFe2O3@CnanocompositesusingFeCl3·6H2Oasironsourceandglucoseascarbonsourceunderalkalinecondition.Themorphologyandstructureoftheas-preparedproductwereidentifiedbytransmissionelectronmicroscopy(TEM),highresolutiontransmissionelectronmicroscopy(HRTEM),field-emissionscanningelectronmicroscopy(FESEM),X-raydiffraction(XRD),Ramanspectroscopy,FourierTransforminfraredspectroscopy(FTIR),andthermogravimetricanalysis(TGA).Theas-prepareα-Fe2O3@Cnanocompositeswereemployedforsupercapacitorelectrodematerial.Thesynergisticcombinationofcarbonelectricaldouble-layercapacitanceandα-Fe2O3pseudo-capacitanceestablishedsuchnanocompositesasversatileplatformforhighperformancesupercapacitors.Thesynthesismethoddevelopedhereisexpectedtoobtainothermetaloxide/carboncomposite.

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简介：TheeuropiumionsdopedMMoO_4(M=Sr,Ba)nanophosphorsweresuccessfullysynthesizedviaafacilehydrothermalmethodusingisopropanol.Therelationshipbetweenphosphorcrystallinephase,morphology,photoluminescentpropertiesandhexadecyltrimethylammoniumbromide(CTAB)concentration,pHvalueinprecursorsolutionwasinvestigated.TheresultsindicatedthatthemorphologyandphotoluminescentpropertieswerestronglyinfluencedbyCTABconcentrationandpHvalueinprecursorsolution.InSrMoO_4:Eu~(3+)hosts,thephosphorsurfacetendedtobecomesmootherastheconcentrationofCTABwasincreased;whileparticlestendedtoagglomerateasincreasingpHvalue.TherelativeintensityratioofchargetransferbandtoEu~(3+)characteristicemissionpeaksofMMoO_4:Eu~(3+)(M=Sr,Ba)waschangedasCTABconcentrationandpHvaluechanged.TheemissionspectraofMMoO_4:Eu~(3+)(M=Sr,Ba)couldbeadjustedbyCTABconcentrationandpHvalueduetotheirimpactsonthestructure.ItwasimportantthatthedifferentmorphologiesandphotoluminescentpropertiesofMMoO_4:Eu~(3+)(M=Sr,Ba)couldbeobtainedbythefacilehydrothermalmethodandmodulatedbychangingCTABconcentrationandpHvalue.

简介：Thispaperpresentsamethodofestablishingahydrothermalore-formingreactionsystem.Onthebasisofthestudyoffourtypicalhydrothermaldeposits,thefollowingconclusionsconcerninggeochemicaldynamiccontrollingduringhydrothermalmineralizationhavebeensionsconcerninggeochemicaldynaamiccontrollingduringhydrothermalmineralizationhavebeendrawn:(1)Theregionaltectonicactivitiescontroltheconcentrationanddispersionofelementsintheore-formingprocessintermsoftheireffectsonthethermodynamicnatureandconditionsoftheore-formingreactionsystem.(2)Duringhydrothermalmineralizationtheactivitesofore-bearingfaultscanbedividebintotwostages:thebrittlesplittingstageandthebrittle-toughtensingstage,whichwouldcreatecharacteristicallydifferentgeodynamicconditionsforthegeochemicalthermodynamicore-formingsystem.(3)Thehydrothermalore-formingreaactionsystemisanopendynamicsystem.Atthebrittlesplittingstagethesystemwassostronglysupersaturatedandunequilibratedastospeedupandenhancethecrystallizationanddifferentiationofore-formingfluids.Andatthebrittle-toughtensingstage,theore-formingsystemwasinaweaksupersaturatedstate;withdecreasingtemperatureandpressurethecrystallizationoforeformingmaterialwouldshowdown,anditcanberegardedasanequilibratedstate.(4)Inthelatesstagesofhydrothermalevolution,goldwouldbeconcentratedintheresidualore-formingsolution.Thepulsatingfractureactiviteinthisstageledtothecrushofpyriteoreanditwasthenfilledwithgold-enrichedsolution,forminghigh-grage“fissure”goldore.Thisore-formingprocesscouldbecalledthecouplingmechanismoforeformation.

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