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1.
将二(4-吡啶)硫烷(L1)、4,4′-二(4-吡啶)二苯甲酮(L2)分别与(Et4N)(Tp*WS3)(A)(Tp*=三(3,5-二甲基吡唑)氢合硼酸根)和[Cu (MeCN)4]PF6进行反应,得到2个W/Cu/S簇基超分子化合物[Tp*WS3Cu2(L1)]2(PF6)2·2MeCN·2CHCl3(1·2MeCN·2CHCl3)和[Tp*WS3Cu2(L2)(MeCN)]2(PF6)2·4MeCN (2·4MeCN)。对配合物1·2MeCN·2CHCl32·4MeCN分别进行了单晶X射线衍射、核磁、质谱、红外、紫外可见和元素分析表征。单晶X射线衍射分析表明,它们是由2个L1/L2配体连接2个[Tp*WS3Cu2]+簇核形成的阳离子型簇基超分子框。核磁氢谱和高分辨电喷雾离子化质谱(HRESI-MS)证明它们在溶液中具有一定的稳定性。并利用Z扫描技术测试了超分子化合物1·2MeCN·2CHCl32·4MeCN溶液的三阶非线性光学特性,测试结果表明它们的三阶非线性光学响应强于前驱体A。  相似文献   

2.
Reaction of a preformed cluster [{(η5-C5Me5)WS3}3Cu7(MeCN)9](PF6)4 (1) in MeCN with LiCl and PPh3 gave rise to a tetranuclear cationic cluster [(η5-C5Me5)WS3{Cu(PPh3)}3Cl](PF6) (2). The title compound 2 was characterized by elementary analysis, IR, UV-Vis, 1H NMR, and its crystal structure was determined by X-ray single crystal diffraction. It belongs to monoclinic, space group P21/c with a=1.799 8(4) nm, b=2.083 6(4) nm, c=1.913 5(4) nm, β=113.63(3)°, V=6.574(3) nm3, Z=4. The cluster cation [(η5-C5Me5)WS3{Cu(PPh3)}3Cl]+ of 2 contains a strongly distorted, cubane-like structure [WS3Cu3Cl] in which one Cl weakly fills into the void of the nido-like [WS3Cu3] fragment with three relatively long Cu-Cl distances. CCDC: 270415.  相似文献   

3.
以3,5-二甲(丙)基-4-氨基-1,2,4-三唑为配体,与CuI在H2O/MeCN混合溶剂热合成了2个构型不同的Cu4I4超分子化合物{[Cu2(aadmtrz) I2]·CH3CN}n(1)和[Cu2(dptrz) I]n(2)(aadmtrz=4-((1-氨乙基)-氨基)-3,5-二甲基-1,2,4-三唑,dptrz=3,5-二丙基-1,2,4-三唑),并进行了元素分析,红外,X射线粉末衍射及单晶衍射等表征。2个配合物中Cu4I4构型不同,配合物1中,Cu4I4簇连结成一个8环椅式-椅式结构,通过配体连接成(4,4)二维菱形格子结构;而配合物2中,Cu4I4簇呈畸变的立方烷结构,构成了含有19.5%孔隙率三维孔洞聚合物,其结构可简化为(3,4)-连接的拓朴结构。同时,在常温下研究了2个配合物的固体荧光性质。  相似文献   

4.
采用一个预制的簇合物(Et4N)2[MoS4(CuCN)2]·H2O(1)和HAc在MeCN中混合反应,生成了一个有趣的二维聚合簇合物(Et4N)3{[MoS4Cu2(m-CN)]2(m’-CN)}·2MeCN (2)。通过元素分析,红外光谱及单晶X-射线衍射分析对簇合物2进行了表征。在2的结构中,前驱体1中的MoS4Cu2簇核得到了保留,并且此簇核作为三重连接点通过单一氰桥和其他相同的簇核相连,形成一个阴离子型的2D (6,3)(蜂窝状)网络。由预制的簇合物1通过醋酸诱导形成的超分子2表明这种简单的合成方法有可能应用到许多其他相关的体系。  相似文献   

5.
基于一系列二氰根铬与[Cu(cyclam)](ClO4)2反应合成了3个氰根桥联Cr-Cu-Cr三核配合物[Cu(cyclam)][Cr(bpmb)(CN)2]2·4H2O(1)(cyclam=1,4,8,11-四氮杂环十四,bpmb2-=1,2-二(2-吡啶甲酰胺基)-4-甲基苯),[Cu(cyclam)][Cr(bpdmb)(CN)2]2(2)(bpdmb2-=1,2-二(2-吡啶甲酰胺基)-4,5-二甲基苯)和[Cu(cyclam)][Cr(bpClb)(CN)2]2·4H2O(3)(bpClb2-=1,2-二(2-吡啶甲酰胺基)-4-氯苯)。单晶衍射结果表明:3个化合物是结构类似的中性三核配合物,均含有氰根桥联的Cr(Ⅲ)-CN-Cu(Ⅱ)-NC-Cr(Ⅲ)连接;磁性研究表明:氰根桥在Cr和Cu离子间传递弱的铁磁耦合作用,基于自旋哈密顿算符Ĥ=-2JCrCuŜCuCr1Cr2)拟合得到它们的磁耦合常数分别是JCrCu=1.53(2) cm-1(1),0.45(1) cm-1(2)和0.73(2) cm-1(3)。  相似文献   

6.
向MoO3, H3PO4和bpy(4,4′-bipyridine)组成的反应体系中分别引入Cd(OAc)2·2H2O 和MnCl2·4H2O, 在水热条件下合成了两种基于还原型钼磷酸盐[P4Mo6O28(OH)3]9-(简称{P4Mo6})为建筑单元构筑的新型多维延展型无机-有机杂化材料(H2bpy)2[Cd(H2O)]3[Cd(HPO4)6(PO4)2(OH)6(MoO2)12]·5H2O(1)和 (H2bpy)3[Mn(H2O)2]2 [Mn(HPO4)6(PO4)2(OH)6(MoO2)12]·10H2O(2), 并通过元素分析、红外光谱、热重分析和X射线单晶衍射对其进行了表征。结果表明, 化合物1和2均属于三斜晶系, P1 空间群。化合物1的阴离子[Cd(H2O)]3[Cd(HPO4)6(PO4)2(OH)6(MoO2)12]2-是由二聚体 Cd[P4Mo6]2通过{Cd3}簇依次连接形成的一维无机链状结构; 化合物2的阴离子[Mn(H2O)2]2[Mn(HPO4)6(PO4)2(OH)6(MoO2)12]3-则是由二聚体Mn[P4Mo6]2通过Mn2+离子连接形成的二维无机层状结构。这2种无机延展结构均同质子化的bpy通过氢键作用形成不同的三维超分子网络。同时还探讨了化合物2的电化学性质。  相似文献   

7.
In the presence of NH4PF6, reaction of [PPh4][(η5-C5Me5)WS3Cu3Br(dppm)] with excess pyridine afforded red prismatic crystals, [(η5-C5Me5)WS3Cu3Br(Py)3(dppm)](PF6) (1). It was characterized by elemental analy-sis, IR, UV-vis and 1H NMR spectroscopy and X-ray diffraction. 1 crystallizes in an orthorhombic system with space group Pna21 and unit cell parameters a=2.1124(4)nm, b=1.8944(4)nm, c=1.3338(2)nm, V=5.3375(19)nm3Z=4, Dc=1.807g·cm-3Mr=1452.42, F(000)=2864, μ=4.342mm-1R1=0.0487, wR2=0.1027. The structure of the cluster cation contains an incomplete cubane-like WS3Cu3 core where Cu(1) and Cu(2) atoms are bridged by a dppm ligand. Each of the three Cu atoms adopts a distorted tetrahedral coordi-nation geometry. The W-Cu(1), W-Cu(2) and W-Cu(3) distances are 0.27698(17)nm, 0.2772(17)nm, and 0.27065(9)nm, respectively. CCDC: 199845.  相似文献   

8.
含硫多吡啶配体及其过渡金属配合物的合成、表征与结构   总被引:1,自引:0,他引:1  
本文报道1个含硫多吡啶配体5,5′-二(2-吡啶硫)甲基-2,2′-联吡啶(L)及其3个过渡金属配合物{[AgL](ClO4)} (1),[CuLCl2] (2)和[Mn(L)3](ClO4)2(H2O)0.5 (3)的合成及结构表征  相似文献   

9.
在本研究中,通过金属定向的分级自组装反应,以芳基吡唑-吡啶配体与双金属钯组装子在水溶液中合成了平行四边形的大环超分子金属环[Pd6(bpy)6(L1)4](PF6)8 (1a)和[Pd6(bpy)6(L2)4](PF6)8 (2a),其中 HL1=1-(1H-pyrazole-4-yl)-4-(4-pyridyl)benzene,HL2=9-(1H-pyrazole-4-yl)-10-(4-pyridyl)anthracene,bpy=2,2''-联吡啶。通过单晶X射线衍射证实了超分子钯平行四边形的结构。值得注意的是,这2个平行四边形金属环可以用作开启型荧光传感器,通过拆卸机制检测HSO3-。此外,基于配合物1a的传感器显示出对HSO3-的选择性检测,不受其他阴离子的干扰。检测限低至0.131 μmol·L-1。此外,配合物1a还通过荧光变化实现了在试纸模式下对HSO3-的半定量可视化检测。  相似文献   

10.
在本研究中,通过金属定向的分级自组装反应,以芳基吡唑-吡啶配体与双金属钯组装子在水溶液中合成了平行四边形的大环超分子金属环[Pd6(bpy)6(L1)4](PF6)8 (1a)和[Pd6(bpy)6(L2)4](PF6)8 (2a),其中 HL1=1-(1H-pyrazole-4-yl)-4-(4-pyridyl)benzene,HL2=9-(1H-pyrazole-4-yl)-10-(4-pyridyl)anthracene,bpy=2,2''-联吡啶。通过单晶X射线衍射证实了超分子钯平行四边形的结构。值得注意的是,这2个平行四边形金属环可以用作开启型荧光传感器,通过拆卸机制检测HSO3-。此外,基于配合物1a的传感器显示出对HSO3-的选择性检测,不受其他阴离子的干扰。检测限低至0.131 μmol·L-1。此外,配合物1a还通过荧光变化实现了在试纸模式下对HSO3-的半定量可视化检测。  相似文献   

11.
Three new sodium cobalt (nickel) selenite compounds, namely, Na2Co2(SeO3)3, Na2Co1.67Ni0.33(SeO3)3, and Na2Ni2(SeO3)3 have been hydro-/solvothermally synthesized in the mixed solvents of acetonitrile and water. Single-crystal X-ray diffraction analyses reveal that these isostructural compounds belong to the orthorhombic Cmcm space group and their structures feature three-dimensional open frameworks constructed by the two-dimensional layers of [MSeO3] pillared by the [SeO3]2− groups. The two different types of Na+ ions reside in the intersecting two-dimensional channels parallel to the a- and c-axes, respectively. Their thermal properties have been investigated via TGA-DSC. The magnetic measurements indicate the existence of the antiferromagnetic interactions in these compounds.  相似文献   

12.
Summary Temperature-programmed desorption (TPD) of CH4, C2H6, C2H4, and CO and temperature-programmed pulse surface reactions (TPSR) of CH4, C2H6, C2H4, CO, and CO/H2 over a Co/MWNTs catalyst have been investigated. The TPD results indicated that CH4 and C2H6 mainly exist as physisorbed species on the Co/MWNTs catalyst surface, whilst C2H4 and CO exist as both physisorbed and chemisorbed species. The TPSR results indicated that CH4 and C2H6 do not undergo reaction between room temperature and 450oC. Pulsed C2H4 can be transformed into CH4 at 400 oC whilst pulsed CO can be transformed into CO2 at 100 or 150oC. In gaseous mixtures of CO and H2 containing excess CO, the products of pulsed reaction were CH3CHO and CH3OH. When the ratio of CO and H2 was 1:2, pulsed CO and H2 were transformed into CH3CHO, CH3OH and CH4. In H2 gas flow, pulsed CO was transformed into a mixture of CH3CHO and CH4 between 200 and 250oC and was transformed into CH4 only above 250oC.  相似文献   

13.
Na3Cu2O4 and Na8Cu5O10 were prepared via the azide/nitrate route from stoichiometric mixtures of the precursors CuO, NaN3 and NaNO3. Single crystals have been grown by subsequent annealing of the as prepared powders at 500 °C for 2000 h in silver crucibles, which were sealed in glass ampoules under dried Ar. According to the X-ray analysis of the crystal structures (Na3Cu2O4: P21/n, Z=4, a=5.7046(2), b=11.0591(4), c=8.0261(3) Å, β=108.389(1)°, 2516 independent reflections, R1(all)=0.0813, wR2 (all)=0.1223; Na8Cu5O10: Cm, Z=2, a=8.228(1), b=13.929(2), , β=111.718(2)°, 2949 independent reflections, R1(all)=0.0349, wR2 (all)=0.0850), the main feature of both crystal structures are CuO2 chains built up from planar, edge-sharing CuO4 squares. From the analysis of the Cu-O bond lengths, the valence states of either +2 or +3 can be unambiguously assigned to each copper atom. In Na3Cu2O4 these ions alternate in the chains, in Na8Cu5O10 the periodically repeated part consists of five atoms according to CuII-CuII-CuIII-CuII-CuIII. The magnetic susceptibilities show the dominance of antiferromagnetic interactions. At high temperatures the compounds exhibit Curie-Weiss behaviour (Na3Cu2O4: , , Na8Cu5O10: , , magnetic moments per divalent copper ion). Antiferromagmetic ordering is observed to occur in these compounds below 13 K (Na3Cu2O4) and 24 K (Na8Cu5O10).  相似文献   

14.
王萌  吴锋  苏岳锋  陈实 《物理化学学报》2008,24(7):1175-1179
通过在硝酸钇水溶液浸渍并焙烧的简单工艺, 在LiCo1/3Ni1/3Mn1/3O2材料表面包覆了一层Y2O3. 采用X射线衍射(XRD), 扫描电子显微镜(SEM), 透射电子显微镜(TEM), 循环伏安(CV)和恒流充放电对包覆和未包覆的LiCo1/3Ni1/3Mn1/3O2进行了测试分析. 结果表明, Y2O3包覆并没有改变LiCo1/3Ni1/3Mn1/3O2的晶体结构, 只存在于LiCo1/3Ni1/3Mn1/3O2的表面; 与未包覆的材料相比, Y2O3包覆后的材料在高电位下具有更好的容量保持率和放电容量. CV测试表明, 包覆层的存在有效抑制了材料层状结构的转变及电极与电解液的负反应.  相似文献   

15.
TiO2包覆对LiCo1/3Ni1/3Mn1/3O2材料的表面改性   总被引:1,自引:1,他引:0  
为了提高材料LiCo1/3Ni1/3Mn1/3O2的循环性能, 采用浸渍-水解法对其进行TiO2包覆. 用X射线衍射(XRD)、电化学交流阻抗谱(EIS)、电感耦合等离子体发射光谱(ICP-OES)和恒流充放电测试研究包覆材料的结构和电化学性能. TiO2仅在材料表面形成包覆层, 并未改变材料的结构. TiO2包覆能提高材料LiCo1/3Ni1/3Mn1/3O2的倍率性能和循环性能, TiO2包覆后的材料在5.0C(1.0C=160 mA·g-1)下的放电容量达到0.2C下的66.0%, 而包覆前的材料在5.0C下的放电容量仅为其0.2C下的31.5%. 包覆后的材料在2.0C下循环12周后的容量没有衰减, 而未包覆的材料容量保持率仅为94.4%. EIS测试表明包覆材料性能的提高是由于循环过程中材料的界面稳定性得到了提高. 循环后材料的XRD和ICP-OES测试表明, 包覆层能提高材料LiCo1/3Ni1/3Mn1/3O2的结构稳定性.  相似文献   

16.
An improved method was developed for simultaneous determination of the fortified forms of thiamine (B1), riboflavin (B2), nicotinamide and nicotinic acid (B3), pantothenic acid (B5), pyridoxine (B6), biotin (B7), and folic acid (B9) in infant formulas and related nutritionals. The method employed a simple, effective, and rapid sample preparation followed by liquid chromatography tandem mass spectrometry (LC-MS/MS). It improved upon previous methodologies by offering facile and rugged sample preparation with improved chromatographic conditions, which culminated in a highly accurate and precise method for water-soluble vitamin determination in a wide range of formulas. The method was validated over six days in ten unique matrices with two analysts and on instruments in two different labs. Intermediate precision averaged 3.4 ± 2.6% relative standard deviation and over-spike recovery averaged 100.2 ± 2.4% (n = 160). Due to refinements in sample preparation, the method had high sample throughput capacity.  相似文献   

17.
在QCISD(T)/6-311++G(d,p)//B3LYP/6-311G(d,p)的水平下计算了乙醇及乙醇燃烧裂解产物与C2H3之间的脱氢反应机理,利用正则变分过渡态理论(CVT)结合小曲率隧道效应模型(SCT)计算400~2000 K范围内的速率,对比OH,H及CH3等自由基相似脱氢反应速率,选择2条具有较快反应速率的通道(C2H3+C2H5OH→TS1→C2H4+C2H5O和C2H3+CH3HCO→TS4→C2H4+CH3CO).将这2个反应耦合到正庚烷/乙醇混合燃料及异辛烷/乙醇混合燃料的机理中,利用CHEMKIN程序中预混火焰模型模拟混合燃料的燃烧过程并进行路径分析.对比相应的实验数据发现,改进的动力学模型对燃烧过程中C2H3路径上相近组分的预测精度有较大改善,而对C2H3路径上较远的组分丙炔(C3H4)和乙烯基乙炔(C4H4)等影响不大.  相似文献   

18.
利用热重研究了两种中国西北典型低阶煤半焦的燃烧特性。探究了不同气氛(O2/CO2、O2/N2和O2/Ar)和不同氧气浓度对其燃烧特性的影响。实验结果表明,无论是反应气氛还是氧气浓度都会对低阶煤半焦的燃烧产生影响。相比于N2和Ar,CO2明显有利于燃烧反应进行:当反应气氛由O2/CO2变为O2/Ar时,两种不同低阶煤半焦的燃尽温度分别升高了63.7和68.8℃;而当反应气氛由O2/CO2变为O2/N2时,两种不同低阶煤半焦的燃尽温度分别升高了135.9和129.6℃。在研究范围内,氧气浓度的提高也能明显提高半焦的燃烧性能。与此同时,半焦燃烧特性的动力学分析表明,随着氧气浓度提高,两种半焦燃烧反应的表观活化能E和指前因子A均呈增大趋势。通过对E和A两者关系的分析结果表明,半焦富氧燃烧的活化能和指前因子存在动力学补偿效应。  相似文献   

19.
(CpCH_2CH_2CH = CH_2)_2MCl_2(M=Zr, Hf)/MAO and Cp_2ZrCl_2/MAO (Cp=cyclopentadienyl; MAO=methylaluminoxane) catalyst systems have been compared for ethylene copolymerization to investigate the influence of theligand and transition metal on the polymerization activity and copolymer properties. For both CH_2CH_2CH=CH_2 substitutedcatalysts the catalytic activity decreased with increasing propene concentration in the feed. The activity of the hafnocenecatalyst was 6~8 times lower than that of the analogous zirconocene catalyst, ~(13)C NMR analysis showed that the copolymerobtained using the unsubstituted catalyst Cp_2ZrCl_2 has greater incorporatien of propene than those produced byCH_2CH_2CH=CH_2 substituted Zr and Hf catalysts. The melting point, crystallinity and the viscosity-average molecularweight of the copolymer decreased with an increase of propenc concentration in the feed. Both CH_2CH_2CH= CH_2 substitutedZr and Hf catalysts exhibit little or no difference in the melting point and crystallinity of the produced copolymers. However,there are significant differences between the two zirconocene catalysts. The copolymer produced by Cp_2ZrCl_2 catalyst havemuch lower T_m and X_c than those obtained with the (CpCH_2CH_2CH=CH_2)_2ZrCl_2 catalyst. The density and molecular weightof the copolymer decreased in the order: (CpCH_2CH_2CH=CH_2)_2HfCl_2>(CpCH_2CH_2CH=CH_2)_2ZrCl_2>Cp_2ZrCl_2. The kineticbehavior of copolymerizaton with Hf catalyst was found to be different from that with Zr catalyst.  相似文献   

20.
采用硅胶为黏结剂,在堇青石蜂窝陶瓷上以涂覆法依次负载Cu、Mn、Ce改性的纳米TiO2粉末、W改性的V2O5粉末得到复合催化剂,在120~550 ℃用尿素选择性催化还原(Urea-SCR)氮氧化物时显示良好活性。与商业催化剂V2O5-WO3/TiO2相比,添加Cu、Mn、Ce后,催化剂脱硝活性显著提高,活性温度窗口明显拓宽。结果表明,催化剂的高活性与催化剂表面适度的酸碱性、高比值的V4+/V5+以及良好的氧化还原性能和锐钛矿相的TiO2、丰富的表面裂纹的存在等因素有关。  相似文献   

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