简介:Aseriesoftitlecompoundsaswellastheirprecursorsweresynthesizedbyprecursorroute.TheirPXRDpatternswerecharacterizedwithZrW2O8orZrMo2O8modelbyRietveldmethod.Thethermalcontractionsofthecompoundsweredeterminedaccordingtothevariable-temperaturePXRDdataandNTEcoefficientswerepresented.Thetwo-phasemixtureofZrW0.4Mo1.6O8wasalsoanalyzedindividually.
简介:Anovelgel-likeprocesshasbeendevelopedforsynthesizingLiaNi0.8Co0.2O2powders,usingcitricacidasachelatingagent.Thisprocessimprovesthehomogeneityofconstituentcationandenhancestheirreactivityintheobtainedprecursor.Theresultsofelectrochemicaltestdemonstratedthatthesematerialsexhibitedexcellentelectrochemicalproperties.Itsinitialcapacityreached181.6mAh/gandreversibleefficiencyatthefirstcycleisabout88.6%.
简介:Theepoxideisakindofversatileintermediateformanufactureofawidevarietyoffinechemicals.Thegoalofmodemefficientcatalyticmethodsistoproducedesiredcompoundswithhighyield,selectivity,lowcost,safety,operationalsimplicityandmoreimportantlyenvironmentallybenignmanner.However,therearevariousoxidants,whichareoftenhazardousorexpensive,beingusedforbothlaboratoryandindustrialepoxidation.Hydrogenperoxide(30wt%)solutionisthoughtasoneoftheidealoxidantsbecausewaterisasoletheoreticalsideproduct.Meanwhiletheepoxidationofstyreneisatypicaloneamongolefins.Here,theperformanceofstyreneepoxidationwasstudiedwithhydrogenperoxidesolutioncatalyzedbyCo(Ⅱ)phenanthrolinecomplexencapsulatedinsupercagesofMCM-41.
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:有spheres-within-a-sphere的合并Cu的订的六角形的mesoporous硅酸盐(Cu-MCM-41)凹陷结构作为合作模板用thermoreversible聚合物hydrogelmethylcellulose(MC)和cationic表面活化剂被综合了,它被扫描电子显微图(SEM)描绘了,X光检查衍射(XRD),传播电子显微图(TEM),并且N2吸附解吸附作用等温线。获得的结果显示合并Cu的MCM-41材料的形态学是“spheres-within-a-sphere”空组织,它很类似于的蜂窝状。在有H2O2的苯hydroxylation,空范围比Cu-MCM-41的粒子显示出许多更高催化的活动。
简介:Achiralrutheniumcomplex[(1S,2S)-DPEN]-RuCl_2(PPh_3)_2(DPEN=1,2-diphenylethylenediamine,PPh_3=triphenylphosphine)wasencapsulatedinthechannelofAl-MCM-41byelectrostaticadsorptionand1,1-dichlorosilacyclobutanemodification.Thepreparedheterogeneouscatalystshowedthesamecatalyticactivityandenantioselectivityasthecorrespondinghomogeneouscatalystintheasymmetrichydrogenationofacetophenone,andcouldbereusedatleastseventimeswithoutsignificantlossofcatalyticactivityandenantioselectivity.
简介:利用密度泛函理论PBE0方法,在6-31G基组水平上,对12种采用不同聚合位点的乙烯基噻吩二聚体分子进行了全优化,得到分子的紫外-可见吸收光谱.探讨了聚合位点对齐聚乙烯基噻吩吸收光谱、电子亲和势、电离能和重组能的影响,并研究了聚合度对乙烯基噻吩齐聚物吸收光谱的影响.计算结果表明:采用邻位聚合的乙烯基噻吩二聚体的能隙最小,电离能EIP最小,电子亲和势EEA最高,最大吸收波长较大,吸收强度大,λmax=377.33nm,f=1.0242.随着聚合度的增加,齐聚乙烯基噻吩的吸收光谱发生红移,吸收峰变宽,吸光度增大.十六聚体的最大吸收范围为500~1200nm,最大吸收波长为801.28nm时吸收值为7.003×10^5L·mol^-1·cm^-1.
简介:采用密度泛函理论B3LYP方法计算了13个13位取代苦参碱衍生物的电子结构,研究了化合物结构与抑制人肝癌细胞HepG2抗癌活性的定量构效关系(QSAR).结果表明:(1)13位取代的苦参碱类衍生物的最低空轨道能ELUMO越低,最低空轨道与最高占据轨道的能隙ΔE越小,化合物抗癌活性越高;(2)分子的能量Etotal、面积S以及体积V越大,其极化度P越大,活性越大;(3)分子的油水分配系数logP越大,活性越大,即分子的疏水性增大活性增强.综合得到了显著性较好的QSAR方程:-lgIC50=97.008-11.759ΔE+818.602QC2-2.132×10-4Etotal,可用于预测该类衍生物抑制人肝癌细胞HepG2的活性并进行分子设计.
简介:采用水热合成方法构建了基于Preyssler型多酸[S5W30O110]的有机-无机杂化材料,其分子式为[HKS5W30O110]·(2,2-Hbpy)8·2H2O(1,bpy=bipyridine).单晶X-射线衍射分析表明化合物1是由S-中心的Preyssler型多酸作为模版,被2,2-联吡啶分子包围形成的核壳结构的有机无机杂化材料.这是第一例基于S-中心Preyssler型多酸的超分子核壳结构.其中质子化的2,2’-联吡啶有机基团通过静电作用与Preyssler型多酸分子构筑成有机无机杂化材料.该化合物属于三斜晶系,空间群为P-1.晶胞参数:a=1.79505(2)nm,b=1.83478(2)nm,c=4.12816(4)nm,α=85.0610(10)°,β=80.6160(10)°,γ=60.7210(10)°,晶胞体积为11.7002(2)nm3.
简介:利用水热方法合成了一种Keggin型多酸基有机无机杂化材料,化学式为(Hpydz)Na[Co(pydz)4(H2O)2][SiW(12)O(40)]·3H2O(pydz=pyridazine).单晶X-射线研究表明,在该化合物中,Keggin型多阴离子与钠离子连接构筑成三维孔状结构,其中钴-哒嗪阳离子有机基团作为客体分子,通过静电相互作用存在于三维孔道结构中,构筑成有机-无机杂化材料.该化合物属于单斜晶系,空间群为C2/c,晶胞参数a=1.9377(2)nm,b=1.6788(2)nm,c=1.7680(2)nm,α=90°,β=98.612(3)°,γ=90°,V=5.68651nm3.