学科分类
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408 个结果
  • 简介:Three-dimensional(3D)flowerlikehierarchicalZn2GeO4andMn2+-dopedZn2GeO4microstructureshavebeenpreparedbyafacilehydrothermalapproach.X-Raydiffraction(XRD),fieldemissionscanningelectronmicro-scopy(FESEM),transmissionelectronmicroscopy(TEM)andphotoluminescence(PL)spectrometrywereemployedtocharacterizethesamples.SuchflowerlikehierarchicalZn2GeO4microstructureswithanaveragediameterof3―4μmwerefoundtobeconstructedbyabundantsinglecrystallinenanorodsofabout90nmindiameter.TheluminescentpropertiesofZn2GeO4:xMnphosphorswithdifferentcontentsofMn2+asanactivatorwereinvestigated.TheMn2+-dopedsamplesshowedgreenluminescencecorrespondingtothed-dtransitionofMn2+undertheirradiationofUVlight.Theredshift(from531nmto538nm)inλemwithincreasingMn2+contentwasobservedintheluminescentspectra,whichshouldbeattributedtoaweakcrystalfieldbecauseofthesubstitutionofZn2+byMn2+atadistortedtetrahedrallatticesite.

  • 标签: 锰掺杂 体系结构 场发射扫描电子显微镜 水热法 透射电子显微镜 X-射线衍射
  • 简介:CarbonylationofAllylChlorideCatalyzedbyPdCl(TPPTS)inTwo-phaseMediumCarbonylationofAllylChlorideCatalyzedbyPdCl(TPPTS)in...

  • 标签: TPPTS
  • 简介:Emissionquenchingof[Ru(bpy)2(4,4’-dcbpy)](PF6)2(1)bybenzenamine,4-[2-[5-[4-[4-dimethylamino]phenyl]-4,5-di-hydro-1-phenyl-1H-pyrazol-3-yl]-ethenyl]-N,N-dimetyl(2)or1,5-diphenyl-3-(2-phenothiazine)-2-pyrazoline(3)wasobserved.Measurementsoftheemissiondecayof1beforeandafteradditionof2or3bysinglephotoncountingtechniquecon-finnedtheobservations.Theemissionquenchingof1by2or3wassubmittedtoStern-Volmerequation.Itwascalculatedthatthequenchingrateconstants(kq)are5.5×109(mol/L)-1s-1for2and4.0×109(mol/L)-1s-1for3,respectively.Theseresultsindicatedacharacterofdynamicquenchingprocess.Thesinglet-stateof2or3wasalsoquenchedby1.ThequenchingbehaviorsdidnotconformtotheStern-Volmerequationandinvolvedbothstaticanddynamicquenchingprocesses.Theapparentquenchingrateconstant(kapp)wascalculatedtobe3×109(mol/L)-1fortheinteractionofexcited2with1,and1.2×109(mol/L)-1forthatofexcited3wit

  • 标签: RUTHENIUM COMPLEXES PYRAZOLINE compounds electrontransfer dynamic
  • 简介:采用量子化学方法研究了CH2ClO2与NO反应机理.计算结果表明,CH2ClO2+NO反应的主导产物为CH2ClO+NO2,CHClO+HNO2,CHClO+trans-HONO,CH2O+trans-ClONO和CH2O+cis-ClONO.其他产物由于需要跨越的能垒太高或者产物不稳定,对整个反应来讲可以忽略.

  • 标签: CH2ClO2 NO 大气反应 反应机理.
  • 简介:采用水热法合成了一种新的超分子化合物{[2-(4-chlorophenyl)benzimidazoleH]2^2+·[SbCl5]^2-}n.通过元素分析、红外光谱、荧光光谱及X射线单晶衍射对其结构和性质进行了测定.结构分析表明;该晶体属于单斜晶系,P21/c空间群,晶胞参数为:a=0.5830(9)nm,b=1.6125(3)nm,c=1.6163(3)nm,β=94.181(2)°,Z=2,化学式为C26H20Cl7N4Sb,Mr=758.36,V=1.5155(4)nm^3,Dc=1.662g·cm^-3,μ=1.551mm^-1,F(000)=748,R1=0.0891,wR2=0.2568.Sb^3+与其周围6个氯离子配位,构成一个6配位的畸变八面体构型,配阴离子与2-(4-氯苯基)苯并咪唑阳离子以静电引力、氢键及π-π堆积作用形成三维网状超分子化合物.荧光测试显示该化合物具有较好的光致发光性能.

  • 标签: 2-(4-氯苯基)苯并咪唑 三维超分子化合物 水热合成 晶体结构 光致发光
  • 简介:HighactiveandstablegoldcatalystssupportedoncrystallineFe2O3andCeO2/Fe2O3werepreparedviathedeposition-precipitationmethod.ThecatalystwithaAuloadof1.0%calcinedat180°CshowedaCOconversionof100%at-8.9°C,whileAu/CeO2/Fe2O3convertedCOcompletelyat-16.1°C.Evenhavingbeencalcinedat500°C,Au/Fe2O3stillexhibitedsignificantcatalyticactivity,achievingfullconversionofCOat61.6°C.ThecatalystwithalowAuloadof0.5%couldconvertCOcompletelyatroomtemperatureandkepttheactivityunchangedforatleast150h.N2adsorption-desorptionmeasurementsshowthatthecrystallinesupportspossessedahighspecificsurfaceareaofabout200m2/g.CharacterizationsofX-raydiffractionandtransmissionelectronmicroscopyindicatethatgoldspecieswerehighlydispersedasnanoorsub-nanoparticlesonthesupports.Evenafterthecatalystwascalcinedat500°C,theAuparticlesremainedinanano-sizeofabout6―10nm.X-rayphotoelectronspectrarevealthatthesupportedAuexistedinmetallicstateAu0.ThemodificationofAu/Fe2O3byCeO2provedtobebeneficialtotheinhibitionofcrystallizationofFe2O3andthestabilizationofgoldparticlesindispersedstate,consequentlypromotingcatalyticactivity.

  • 标签: 金催化剂 CO氧化 氧化铁 Au/Fe2O3 去甲肾上腺素 X射线光电子能谱
  • 简介:利用水热法首次合成了具有两种配位环境Cd原子的新型杂多蓝化合物[NH3(CH22NH3]5[Cd(H2O)][CdMo12^vO30(HPO4)6(H2PO4)2]·5H2O.通过元素分析、ICP、TG和X射线单晶衍射确定了其组成,使用IR和EPR进行了结构表征.通过N2吸附脱附测定了比表面积和孔径,为催化研究提供了基础数据.结果表明:该晶体为三斜晶系,P-1,空间群;晶胞参数a=1.2002(2)nm,b=1.4651(3)nm,c=2.1192(4)nm,V=3.5642(12)nm^3,p=83.01(3)°,Z=2,F(000)=2932,R1=0.0300,wR2=0.0716.

  • 标签: 杂多蓝 水热合成 晶体结构 中孔材料
  • 简介:以硅酸钠为原料,CTAB为模板剂,水热法合成MCM-41介孔分子筛,采用浸渍法制备负载钴的介孔分子筛(Co/MCM-41),并将其作为催化剂,CVD法热解无水乙醇制备CNTs.利用XRD、TEM、比表面积和孔径分布测定和Raman光谱等方法对所合成的介孔分子筛和纳米碳管进行了表征.结果表明:所制备的Co/MCM-41样品具有典型的MCM-41的介孔结构;当热解反应温度为750℃下所制备出的纳米碳管的品质最好.

  • 标签: 介孔分子筛 纳米碳管 负载 乙醇 催化热解
  • 简介:应用聚硅纳米材料在油田注水井中降压增注的室内实验表明,纳米聚硅材料能够改变岩石润湿性、提高水相相对渗透率,一同时说明聚硅材料易吸附于岩石表面能改变界面性质,其强憎水特性能够驱替吸附在孔隙内表面的水膜,扩大孔径.所以纳米聚硅材料能降低注水压力,提高注水量,具有较好的经济效益.

  • 标签: 纳米聚硅材料 低渗透油田 降压增注 相对渗透率 润湿性 吸附性
  • 简介:Yb3+complexeswithtwonitrilotriaceticacidmoleculeswerepreparedandtheircompositionsweredeterminedasK3[Yb(nta)2(H2O)]*5H2OandNa3[Yb(nta)2]*6H2Obyelementalanalyses.Theirstructureswerecharacterizedbysingle-crystalX-raydiffractionanalyses.IncomplexK3[Yb(nta)2(H2O)]*5H2O,theYbN2O7partformsanine-coordinatemonocappedsquareantiprismaticstructure.IncomplexNa3[Yb(nta)2]*6H2O,theYbN2O6partformsaneight-coordinatesquareantiprismaticstructure.Itcanbeseenthattheoutercations(K+andNa+)greatlyaffectthecoordinationnumberandcoordinatestructurefromtheseresults.

  • 标签: 次氮基三乙酸 镱配合物 合成 晶体结构 X射线衍射
  • 简介:2-Phenyl-1,2,3-triazole-4-formylhydrazine(2)waspreparedbyhydrazinolysisofthecorrespondingester1.Reactionof2withCS2/KOHgavetheoxadiazolederivatives(3)whichvia,Mannichreactionwithdifferentdialkylaminesfurnished3-N,N-dialkylderivatives(4a-c).Also,condensationof2withappropriatearomaticacidinPOCl3yieldedoxadiazolederivatives(5a-c),orwithaldehydesandketonesaffordedhydrazones(6a-c).Cyclizationof(6a-c)withaceticanhydridegavethedesireddihydroxadiazolederivatives(7a-c).Ontheotherhand,reactionofdithiocarbazate(8)withhydrazinehydrategavethecorrespondingtriazolederivative(9)whichontreatmentwithcarboxylicacidsinrefluxingPOCl3yieldeds-triazole[3,4-b]-1,3,4-thiadiazolederivatives(10a-b).ThestructuresofalltheabovecompoundswereconfirmedbymeansofIR,1HNMR,MSandelementalanalysis.

  • 标签: 2-Phenyl-1 2 3-triazole 1 3 4-oxadiazole
  • 简介:2,5-piperazinedione的新衍生物,1,4-di(2-methoxyphenyl)-2,5-piperazinedione(I),被N-2-methoxyphenylchloroacetamide,和它的结构的cyclocondensation反应综合被元素的分析,红外,1HNMR和单身者描绘水晶X光检查衍射方法。水晶属于单斜晶的系统,有统一房间尺寸a=0.56934(10)nm的空格组P21/c,b=1.3880(2)nm,c=1.00329(17)nm,=90.376(3)?e

  • 标签: 1 4-二(2-甲氧基苯基)-2 5-哌嗪二酮 合成 晶体结构 特性
  • 简介:对化合物[Na_2(H_2O)_(10)][Cu_4(H_2O)_(12)(H_2W_(12)O_(42))]·15H_2O(简称Na_2Cu_4W_(12))进行了体外抗肿瘤活性研究.应用四甲基偶氮唑盐(3-[4,5-dimethylthiazo-2-y]-2,5-diphenyltetrazoliumbromide,MTT)比色法分析Na_2Cu_4W_(12)对人肝癌细胞(HepG2)、人神经母细胞瘤细胞(SHY5Y)增殖抑制活性.采用光学显微镜观察肿瘤细胞的凋亡形态变化,用流式细胞术分析细胞周期和细胞凋亡,计算各期细胞比例及细胞凋亡率.结果表明,Na_2Cu_4W_(12)对HepG2和SHY5Y2种肿瘤细胞增殖半数抑制浓度IC_(50)值分别为5.3和10.2μmol·L~(-1),且呈剂量依赖性.光学显微镜下处理组细胞出现皱缩、变圆、缩小等形态变化,不同浓度Na_2Cu_4W_(12)处理12h早期凋亡细胞所占的百分比显著增加且呈剂量依赖性.综上所述,Na_2Cu_4W_(12)能够抑制胞瘤细胞增殖,诱导细胞凋亡.

  • 标签: 仲钨酸盐化合物 抗肿瘤 体外研究
  • 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.

  • 标签: 苯乙酮 MCM 不对称氢化 Al 封装 非均相催化剂
  • 简介:Thesynthesisof(S)-2-(3-arylacrylamido)-3-{4-[2-(5-methyl-2-phenyloxazol-4-yl)ethoxy]phenyl}propanoicacidsisdescribed.TheirstructureswereconfirmedbyH-NMR.

  • 标签: 丙酸 合成方法 分子结构 核磁共振
  • 简介:The2-C,methylenegroupof1-aroyl-1,2-dihydro-3H-naphtho[2,1-b]pyran-3-ones(2)havebeenshowedtopossessasuperiorreactivitytowardsmanyoforganicreagents.Thena-phthopyrones(2)condensedwitharomaticaldehydestogivethe2-arylidinederivatives(3).Bromin-ationof2gave1,2-dibromo(4)or5-bromo(5)derivativesdependingonthereactionconditions.Thebasecatalyzedadditionorcycloadditionofnaphthopyrones(2)to4-methoxybenzalacetophenonegavetheexpectedMichaeladduct(6)orthecyclicadducts(7-9)dependingonthetypeofcatalyticbaseandreactionconditions.Structuresoftheproductshavebeenestablishedbyelementalanalyses,IRand~1HNMRspectroscopicmethods.

  • 标签: PYRAN REACTIVITY aldehydes aromatic bromo catalyzed
  • 简介:将热分解法应用于费-托合成模型催化剂的设计合成,并对一系列制备条件进行了系统的研究.结果显示,前驱体与载体物质的量比、搅拌速率和升温速率都对催化剂的分散度和颗粒的均一性有很大的影响.前驱体与载体比过大会导致颗粒致密堆叠,过小会导致颗粒过于分散.搅拌速率过慢会导致部分颗粒不依附载体生长,导致团聚;而转速过快会导致部分小颗粒形成大团簇.另一方面,升温速率会明显影响颗粒在载体上的成核结晶,进而影响颗粒的粒径大小,颗粒粒径会随着升温速率的增加而增加.当前驱体与载体物质的量比为0.024,搅拌速率为1800r/min,升温速率为8℃/min时,催化剂分散良好,粒径为16.9nm,催化剂负载量为11%,将此催化剂进行费-托合成反应性能测试发现催化剂在210℃,1.0MPa时转化率达到28.5%,C5+选择性达到85.5%,反应后催化剂形貌与结构得到了保持.

  • 标签: 费-托合成 模型催化剂 氧化亚钴 碳球 纳米颗粒
  • 简介:TheepoxidationofallylchloridewithH2O2onTi-ZSM-5preparedbyisomorphoussubstitutionofHZSM-5withTiCl4gaswasstudied.TheresultsshowthatTi-ZSM-5hasahighcatalyticefficiencyfortheepoxidationofallylchloride.TheH2O2utilizationreaches99.50%whentheallylchloride/H2O2molarratiois>1.Theeffectofsolventspecies,catalystconcentration,H2O2andallylchlorideconcentrationandreactiontemperatureontheepoxidationwasinvestigatedsimultaneously.Itisfoundthatmethanolisthebestsolventforthereaction.Thereactionrateequationwithv=k[Cat.][H2O2]1/2-[C3H5Cl]andtheapparentactivationenergywithEa=63.462kJ/molareobtainedaccordingtothekineticsstudy.

  • 标签: TI-ZSM-5 EPOXIDATION of ALLYL chloride epichloro-hydrin