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500 个结果
  • 简介:研究了YBaCuO6~7超导催化剂上CO的加氢制醇反应。考察了温度、压力和空速等条件对催化剂反应性能的影响。反应的主要产物是甲醇、CO和少量甲醚。利用XPS、XRD和AFM等技术对催化剂的结构、铜的存在状态和反应活性位进行表征发现,在反应过程中,YBaCuO6~7由orthombic相转变为tetragonal相。反应活性位可能是Cu(I)物种。反应后催化剂颗粒的分散程度明显提高

  • 标签: CO2加氢 YBa2Cu3O6~7超导催化剂 结构 活性位
  • 简介:在CCSD(T)/6-311G(d,p)∥B3LYP/6-311G(d,p)水平上给出了反应C2H3+NO2的详细势能面信息,并列出了中间体和过渡态的几何构型.通过深入分析反应路径及反应机理,得到5个能量可行的产物和6条反应通道,其中产物C2H3O+NO的形成更有利,而产物CH2CO+HNO则是次要产物,其他产物在通常条件下可以忽略.

  • 标签: C2H3 NO2 反应势能面 乙烯自由基 过渡态 二氧化氮
  • 简介:在传统的利用化爆和二级轻气炮作为驱动源的状态方程阻抗匹配实验中,为了考核不同标准材料的可信度,采用了标准材料交叉检验技术。即依次利用这些标准材料作为测量某个待测材料测量雨贡纽线的标准材料,通过比较待测材料雨贡纽线数据的一致性实现对这些标准材料的检验。2004年在神光-Ⅱ装置上完成的二倍频激光Al-Cu和Cu-A1阻抗匹配实验,是一种交叉实验。这两类实验不仅铝、铜二者互为标准材料和待测材料,而且实验包含了正反阻抗匹配两种类型:铝-铜正阻抗匹配实验中冲击波由低阻抗铝进入高阻抗待测材料铜,铜-铝反阻抗匹配实验中冲击波由高阻抗铜进入低阻抗待测材料铝中。

  • 标签: 匹配实验 阻抗匹配 标准材料 铜-铝 检验技术 材料测量
  • 简介:The2-Dheteronuclearcoordinationpolymer{[Ag4Fe2(SCN)12(H2O)2][(inaH)2(H2O)2]}n(1)(inaHistheabbreviationofprotonatedisonicotinicacid)withchemicalformulaC24H20Ag4Fe2N14O8S12hasbeensynthesizedandcharacterizedbysinglecrystalX-raydiffraction,elementalanalysisandIRspectroscopy.TheAgES2ringsconnecttwokindsofoctahedralgeometriesofFe(Ⅲ)ions,[Fe(NCS)6]^3-and[Fe(H2O)E(NCS)4]^-unitswithbridgingthiocyanateionsleadingto2-D[Ag4Fe2(SCN)12(H2O)2]^2-anionframework.Fourkindsofringsincludingtheunprecedentedthirty-twomemberedAg4Fe4(SCN)8ringssharecomersoredgesinthe2-Danionlayerstructure.AllthiocyanatescoordinatetothemetalionsaccordingtotheHSABprinciplewithNatomsbindingtotheFe(Ⅲ)ionsandwithSatomsbindingtoAg(I)ions.Pronoatedinacationsstabilizethelayerstructureascounterionsandhydrogenbondswereformedwithinthepronoatedinacationsdimerandbetweenthedimersandthelatticewaters.Crystaldata:Mr=1560.44,triclinic,P-↑1,a=0.76082(1)nm,b=0.9234nm,c=1.85611(4)nm,α=103.0170(10)°,β=93.7780(10)°,γ=97.4080(10)°,V=1.25385(3)nm^3,Z=1,μ(MoKα)=2.650mm^-1,Dc=2.067g·cm^-3,F(000)=758,R1=0.0412,wR2=0.1003.

  • 标签: 合成 晶体结构 异核核糖核酸 有机聚合物
  • 简介:Anewkindofmonomerswassuccessfullysynthesizedbythereactionbetween2-chloromethylcycloketalandtrimethylsilylcyanide,followedbyringclosureanddehaiogenation.Polymerizationsofthemonomerswerecarriedoutinbenzenesolutionat80℃withbenzoylperoxideasinitiator.BoththestructuresofmonomersandpolymerswerecharacterizedbyIR,1HNMR,13CNMRandelementalanalysis.

  • 标签: Free RADICAL RING-OPENING POLYMERIZATION BIODEGRADABLE
  • 简介:TheNdCl3/MgCl2bisupportedcatalystwaspreparedbyusingNdCl3,MgCl2,(CH32(CH22OHandTiCl4.ItisshownthatthestructureofbisupportedcatalystwasdifferentfromthoseofeitherNdCl3orMgCl2singlesupportedcatalyst.Apeculiartypeofkineticcurveforethylenepolymerizationwasfound.

  • 标签: NdCl3 MgCl2 Bisupported CATALYST OLEFIN POLYMERIZATION
  • 简介:TheNd2O3nanoparticleswhichmodifiedbyAOTwaspreparedusingmicrioemulsionmethodinthesystemofwater/xylene.L3edgeXAFSwasusedtodeterminethedifferenceofthelocalstructurearundNd^3+ionandtheelectricalstructurebetweenthenanocystallineNd2O3andthecoarsebulkmicrocrystallineNd2O3.ItwasfoundthatNd-Odistanceincreasedwiththeformofnanocrystalliteandtheintensityofabsorptionedgealsoenhancedatthesametime.

  • 标签: EXAFS研究 ND2O3 毫微米粒子
  • 简介:Inthisletter,Fe2O3UFP(UltrafineParticles)hydrosolandorganosolwithhighthirdorderopticalnonlinearsusceptibility(3)havebeenreportedforthefirsttime.ThesurfacialmodificationofFe2O3UFPwithdodecylbenzenesulfonateions(DBS)canenhancethenonlinearopticalresponsethroughinterfacialconfinementofelectronmotion.Theinvolvedmechanismisdiscussed.

  • 标签: CONFINEMENT INTERFACIAL SUSCEPTIBILITY ULTRAFINE hinder coated
  • 简介:Tetrabutylammoniumorpotassiumsaltsoforganometalllicderivativesoflacunarypolyanion(RM)3P2W15O59^n-(RM=CpTi,CpZr,C4H7O2SnorC5H9O2Sn)havebeenpreparedandstructurallycharacterizedbyelementalanalysis,IR,UV-Vis,^1HNMRand^183WNMRspectroscopies.Thetitlecomplexesexhibitantitumoractivityinvitro.

  • 标签: 抗癌抗菌素 抗癌活性 合成 结构 多氧钨酸盐
  • 简介:Theabinitiomolecularorbitalmethodisemployedtostudytheenantioselectivereductionofacetophenonewithboranecatalyzedbythiszolidino[3,4-c]oxazaborolidine.Computationresultshowsthatthecontrollingstepforthereductionisthedecompositionofthecatalyst-alkoxyboraneadductandthereductionleadstoS-alcohols.ThetransitionatateofthehydridetransferfromtheboranemoietytothecarbonylcarbonofacetophenoneisatwistedchairstructurewithaB(2)-N(3)-BBH3-HBH3-CCo-OCO6-memberedring.

  • 标签: 噻唑 Ab inito 量子化学 结构
  • 简介:Lophenol,cholest-4α-methyl-7-en-3β-ol(1),obtainedfromDracaenacochinchinensis(Lour.)S.C.Chen,wasstructurallymodified.Itwasacetylatedtoprotect3β-hydroxylgroup,andthenoxidisedbyseleniumdioxideinaceticacidtogivecholest-4a-methyl-8-en-3β,Ta-dioldiacetate(3).Thiscompound3isunstableinchloroformsolutionorwhenheatedandeasilyconvertedtoadienecompound,cholest-4a-methyl-7,14-dien-3β-olacetate(4).Thestructuresof3and4wereelucidatedbymeansofIR,^1HNMR,^13CNMRandMS,andtheabsoluteconfigurationof3wasestablishedbyX-raycrystallography.Thepropertyof3wasalsodiscussedinthispaper.Both3and4arenewcompoundsandwerereportedforthefirsttime.

  • 标签: 胆甾基-4α-甲基-8-烃-3β 7α-二醇双乙酸盐 氧化反应 单晶体 生物活性 化学结构
  • 简介:运用G98W程序,采用Lan12dz基组,对茂金属配合物[2,5-(Me3Si)2MeC5H2FeI(CO)2]进行从头算研究,探讨了配合物结构单元的稳定性、分子轨道能量、原子净电荷布居规律,以及一些前线分子轨道的组成特征等.结果表明,标题配合物在能量上可作为结构单元而稳定存在.该结构单元为茂金属配合物的合成、分子组装分析和催化活性研究提供理论依据.

  • 标签: 茂金属 从头算 电子结构
  • 简介:Thesolidaddofthefirstprotonatedzincoborophosphate,(H3O)Zn(H2O)2BP2O8·H2O(1),wassoventothermallysyn-thesizedbythereactionofZn(NO3)2·6H2OandH3BO3withH3PO4inamixedsolvent,andstructurallycharacterizedbysingle-ystalX-raydiffractionanalysis.ItcrystallizesinthehexagonalP6122,a=0.9604(4)nm,c=1.5297(6)nm,V=1.2218(8)nm^3,Dc=2.921g/cm^3,Z=6,F(000)=1080,μ=3.495mm^-1.Thestmchwefeaturesthatthetetrahedra-te-trahedrahdlcesinterconnectedbyoctahedraandstronghydro-gembondinteractionsformathree-dimensionalframework.Theprotonatedwatermoleculesarelocatedatuniquepositions.othercharacterizationsbyIRandthermalanalysisarealsode-scribed.

  • 标签: (H3O)Zn(H2O)2BP2O8·H2O 合成 结构 质子化 螺旋带状物 硼磷酸锌化合物
  • 简介:用Co2(CO)8与CH3CSNH2反应制得产物Ⅰ,又用Na2Fe(CO)4与Ⅰ反应制得产物Ⅱ(Ⅰ:Co3(μ3-S)(CO)7(CH3CSNH),Ⅱ:Co2Fe(μ3-S)(CO)7(CH3CSNH).通过元素分析。IR、UV、1HNMR、MS表征并用X射线衍射法测得Ⅱ的单晶结构.该簇合物属三斜晶系、PT空间群,晶胞参数:a=0.9203(1),b=1.1296(2),c=1.1425(2)nm;α=116.40°(2),β=101.92°(2),γ=92.58°(1);z=2,V=1.2162nm3,Dc=1.698cm3,μ=21.89cm-1.结构分析表明,Co2FeS构三角锥分子骨架,所有CO均为端基配体,S1为面桥基配体,CH3CSNH为双齿配体,与Co、Fe形成五元环结构.

  • 标签: 簇合物 三角锥分子骨架 硫代乙酰胺
  • 简介:USINGFINITEGEOMETRIESTOCONSTRUCT-PBIB()DESIGNSAND-DESIGNS¥YANGBENFU(DepartmentofMathematics,ChengduTeachersCollege,Chengdu...

  • 标签: FINITE GEOMETRY design.
  • 简介:Thecrystalstructureof[Ni(TAAB)(py)2](BF42,whereTAABisthetetradentatemacrocyclicligandtetrabenzo[b,f,j,n][1,5,9,13]tetraazacyclohexadecine,hasbeendeterminedfromX-raydiffractionanalysis.Thecrys.taibeiongstomonoclinic,spacegroupP21/nwithcellparameters

  • 标签: MONOCLINIC shaped BRIDGED PYRIDINE BENZALDEHYDE editorial
  • 简介:Underdifferentreactionconditions,theexpectedandunexpectedreactionproducts(ofwhichX-raycrystallographicstructurewaspresented)ofetherificationof2-per(poly)fluoroethyl4-substitutedphenolwithβ-haloethanolcanbeobtainedrespectively.

  • 标签:
  • 简介:在这份报纸,为在管的超声的内部流动的调查的马赫4超声的风隧道的轮廓第一被描述。第二,2和马赫4伪吃惊在方形的管挥动的马赫的地点,结构和特征被颜色schlieren相片和管墙压力调查变化大小。最后,墙砍有马赫4伪吃惊的方形的管的墙挥动的方面,顶和底部上的压力分布是由shear的调查品质上压力敏感的液体水晶可视化方法。在第一震动下面的方面墙边界层分离区域在最高的墙附近是狭窄的,当在第一震动下面的方面墙边界层分离区域在底部墙附近是很宽的时。关键词超声的内部流动-伪吃惊波浪-流动可视化-砍压力敏感的液体水晶CLC数字O357.4+2

  • 标签: 超声内流 假振波 剪切应力敏感液晶 管壁压力涨落测量
  • 简介:Aseriesof2’-purineandpyrimidinederivativesof1’,4’-anhy-dro-2’-deoxy-D-arabitol(1)and1’,4’-anhydro-2’-deoxy-D-altritol(2)weresynthesizedregio-andstereo-selectivelyfromD-sorbitolthroughsomeconversioninhighyields.

  • 标签: STEREOSELECTIVE SYNTHESIS 2’-isonucleosides D-sorbitol