简介:NovelhybridmaterialscontainingcovalentlybondedTerbium-benzoicacidcomplexinmesoporoussilicaSBA-15(denotedasTb-SBA-15)werepreparedviaco-condensationoftetrethoxysilane(TEOS)andN-(4-benzoicacid-yl),N'-(propyltriethoxysilyl)urea(denotedasPABI).XRD,FTIRandluminescencespectroscopywereemployedtocharacterizeTb-SBA-15.Whenmonitoredbytheligandabsorptionwavelength(270nm),Tb-SBA-15displaystheemissionofTb3+(5D4→7Fj(j=6,5,4,3)transition)duetotheenergytransferfromtheligandstoTb3+.
简介:目的制备塞来昔布(CEL)/介孔硅SBA-15的固体分散体并进行性质研究。方法利用溶剂吸附平衡法制备CEL/SBA-15固体分散体,通过测定表观溶解度考察水溶性,通过热分析(DSC)和溶出试验考察药物溶出行为、药物存在状态及物理稳定性。结果确定了CEL/SBA-15固体分散体的制备方法。固体分散体载药量约37%,溶解度约为原料药的2倍以上,30min内药物的累计溶出就超过90%,药物以非晶状态存在,加速试验6个月溶出和存在状态稳定。结论CEL/SBA-15固体分散体物理稳定性良好,明显提高难溶药物的水溶性和溶出速率,改善药物的口服吸收。
简介:Ni2P/ZrO2-SBA-15catalystswithdifferentzirconiumn-propoxide/SBA-15massratiosweresynthesizedtoevaluatetheirdibenzothiophenehydrodesulfurizationcatalyticactivity.EffectofZrO2introductionwasinvestigated.SupportsandcatalystswerecharacterizedbyBET,XRD,29SiNMR,XPSandFTIR.TheresultsindicatedthatzirconiumwasincorporatedintoSBA-15intheformsof[(–O–)2Si(–O–Zr)2]and/or[(–O–)3Si–O–Zr],andthattheSBA-15frameworkstructurewasmaintainedafterincorporationofZrO2.Withzirconiumcontentincreasing,ZrO2wastransformedfromamorphousphasetotetragonalphase.ZirconiumincorporationintoSBA-15supportscouldfacilitatetoformmoredispersedNi2Pactivephase.TheremightbesomeinteractionoccurringbetweenthePandZrspecies.InadditiontoNi2P,anotherkindofactivephase,ZrP,wasformed,whichmightexhibitabetterHDSactivitythanNi2P.Itwasobservedthatatatemperatureof280°C,pressureof3.0MPa,WHSVof6.5h?1andH2tooilratioof450,theNi2P/Zr-SBA(1.5)catalyst,where1.5representszirconiumn-propoxide/SBA-15massratio,showedthehighestDBTconversion,whichwas86.6%,almost35%higherthanthatoftheNi2P/Zr-SBA(0)catalyst.
简介:Phasebehaviorofbinarysystemofbromobenzene-chlorobenzene(C6H_5Br-C_6H_5Cl)confinedinSBA-15andMCM-41(porediameter8nm,3.8nm,respectively)hasbeeninvestigatedbymeansofdifferentialscanningcalorimetry(DSC).PhasediagramofC_6H_5Br-C_6H_5ClsystemconfinedinSBA-15isatypeofthecompletemisciblebothinliquidandsolidstate,thesamephasebehaviorasthebulksystem.However,thephasediagramcomprisesonlyoneboundaryline,whichisshifteddown22-36Kwithrespecttothebulksystem.C_6H_5Br,C_6H_5ClorthemixturewithinnanoporesofMCM-41isnonfreezing.ThedifferentphasebehaviorofthesystemconfinedinSBA-15andMCM-41isthoughtmainlyduetotherelativesizeofporetomolecule.
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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