Synthesis,Crystal Structure and Theoretical Calculations of a New Two-dimensional Co(Ⅱ) Coordination Polymer Based on Oxalic Acid and Bis(imidazol) Ligands

A new Co(Ⅱ) coordination polymer has been successfully synthesized under hydrothermal conditions [Co(C2O4)(mbix)]n(1, H2C2O4 = oxalic acid, mbix = 1,3-bis(imidazol-1-ylmethyl)benzene). Its structure has been determined by elemental analyses, IR, UV spectroscopy and single-crystal X-ray diffraction analysis. Pink crystals crystallize in the triclinic system, space group P1 with a = 8.8666(7), b = 9.5859(8), c = 10.8537(9) , α = 67.6810(10), β = 66.1260(10), γ = 77.1300(10)°, V = 777.77(11), C16H14CoN4O4, Mr = 385.24, Dc = 1.645 g/cm3, F(000) = 394, Z = 2, μ(Mo Kα) = 1.134 mm-1, the final R = 0.0482 and w R = 0.1231 for 2968 observed reflections(Ⅰ 2σ(Ⅰ)). It shows a two-dimensional(2D) network structure. The intermolecular C–H···O hydrogen bonding and π-π stacking interactions extend complex 1 into a 3D supramolecular architecture andplay an important role in stabilizing 1. In addition, Natural Bond Orbital(NBO) analysis was performed by using the PBE0/LANL2 DZ method built in Gaussian 09 Program. The calculation results showed obvious covalent interaction between the coordinated atoms and Co(Ⅱ) ion.     

Bi2MoO6/BiVO4异质结的水热合成和可见光催化活性

采用一步水热法制备Bi₂MoO₆/BiVO₄复合光催化剂. 利用X 射线衍射(XRD)、场发射扫描电子显微镜(FESEM)、高分辨透射电子显微镜(HRTEM)等手段对其晶体结构和微观结构进行了表征. 结果表明, Bi₂MoO₆纳米粒子沉积在BiVO₄纳米片表面从而形成异质结结构. 紫外-可见漫反射光谱(UV-Vis DRS)表明所制备的Bi₂MoO₆/BiVO₄异质结较纯相Bi₂MoO₆和BiVO₄对可见光吸收更强. 由于形成异质结结构及其光吸收性能使Bi₂MoO₆/BiVO₄ 光催化活性有较大提高. 可见光下(λ>420 nm)光催化降解罗丹明B (RhB)实验结果表明,Bi₂MoO₆/BiVO₄光催化活性较纯相Bi₂MoO₆和BiVO₄高. Bi₂MoO₆/BiVO₄样品光催化性能提高的原因是Bi₂MoO₆和BiVO₄形成异质结, 从而有效抑制光生电子-空穴对的复合, 增大了可见光吸收范围及比表面积.     

Hydrothermal Synthesis and Crystal Structure of a Zinc（Ⅱ） Polymer with a Two-dimensional Layer Structure： [Zn（pzdc）（phen）]n·nH2O

A metal-organic coordination compound formulated as [Zn（pzdc）（phen）]n·nH2O 1 （H2pzdc = pyrazine-2,3-dicarboxylic acid, phen = 1,10-phenanthroline） has been hydrothermally synthesized and structurally characterized by elemental analysis, IR, fluorescence spectrum and single-crystal X-ray diffraction. The title compound crystallizes in the monoclinic system, space group P21/n with a = 11.607（2）, b = 11.719（2）, c = 13.140（3）A^°, β = 110.707（3）°, V= 1671.9（6）A^°3, C18H12ZnN4O5, Mr= 429.69, De = 1.707 g/cm^3,μ（MoKa） = 1.511 mm^-1, F（000） = 872, Z = 4, the final R = 0.0356 and wR = 0.0853 for 2713 observed reflections （I 〉 2σ（I））. It exhibits an interesting two-dimensional layer structure and shows yellow photoluminescent property at room temperature.     

Hydrothermal Synthesis and Crystal Structure of a New One-dimensional Nickel(Ⅱ) Complex with 2-Pyridinecarboxyic Acid and 4,4′-Bipyridine Ligands

A new metal-organic coordination polymer [Ni[(2-pya)2(4,4′-bipy)]n·6nH2O (2-pya = 2-pyridinecarboxylic acid, 4,4′-bipy = 4,4′-pyridine) 1 has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, TG and single-crystal X-ray diffraction. The complex crystallizes in tetragonal, space group I41/a with a = b = 22.5642(19), c = 10.7118(18), V = 5453.8(11) 3, C22H28N4NiO10, Mr = 567.19, Dc = 1.382 g/cm3, μ(MoKα) = 0.769 mm-1, F(000) = 2368, Z = 8, the final R = 0.0572 and wR = 0.1254 for 1401 observed reflections (I > 2σ(I)). It exhibits a one-dimensional chain-like structure by mixed ligands of 2-pyridinedicarboxylic acid and 4,4′-pyridine.     

Hydrothermal Synthesis and Crystal Structure of a New One-dimensional Cobalt（Ⅱ） Complex with 2-Pyridinecarboxyic Acid and 4,4＇-Bipyridine Ligands

A new metal-organic coordination polymer [Co（2-pya）2（4,4＇-bipy）]2n-[（4,4＇- bipy）0.5· H2O]2n （2-pya = 2-pyridinecarboxylic acid, 4,4＇-bipy = 4,4＇-bipyridine） 1 has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, TG and single-crystal X-ray diffraction. The complex crystallizes in tetragonal, space group I41/a with a = b = 22.719（2）, c = 10.710（2）/k, V = 5527.8（14） A3, C54H46N10Co2O10, Mr= 1112.87, Dc = 1.337 g/cm3,μ（MoKa） = 0.665 mm-1, F（000） = 2296, Z = 4, the final R = 0.0633 and wR = 0.1096 for 1261 observed reflections （I 〉 2σ（I））. It exhibits a one-dimensional chain-like structure constructed by mixed ligands of 2-pyridinedicarboxylic acid and 4,4＇-bipyridine.     

大型液体火箭姿控与跷振大回路耦合动力学建模与分析

大型液体火箭结构模态的空间化分布特征导致结构振动、姿态运动和推进系统液路脉动存在相互耦合,进而影响传统姿控回路的稳定性. 针对大型液体火箭, 充分考虑姿态控制系统对箭体姿态动力学和弹性振动的影响, 以及箭体结构弹性振动与推进系统的耦合作用(跷振(POGO)), 建立了姿控与跷振大回路耦合模型. 该模型包含了推进系统、结构系统与姿控系统之间的耦合因素, 可进行姿控-结构-推进大回路耦合机理研究. 该模型具有非奇异的优点, 可以直接用于频域分析和时域仿真. 基于该模型研究了我国某型号液体捆绑火箭推进系统参数——泵增益和蓄压器能量值对姿态运动与结构振动稳定性的影响. 研究得出, 泵增益和蓄压器能量值的变化不仅导致了结构振动的不稳定, 而且也导致了姿态运动的发散. 因此, 对于大型液体捆绑火箭, 推进系统与姿控系统之间存在不可忽略的耦合作用, 在设计姿控系统时, 有必要考虑推进系统对姿控系统稳定性的影响.      

Hydrothermal Synthesis and Crystal Structure of a Manganese（Ⅱ） Complex：Mn_（1.5）（cbba）_3（phen）

A new metal-organic complex Mn1.5(cbba)3(phen)(Hcbba = 2-(4'-chlorine-ben-zoyl)benzoic acid,phen = 1,10-phenanthroline) 1 has been hydrothermally synthesized and struc-turally characterized by single-crystal X-ray diffraction,elemental analyses,TG and IR spectro-scopy.The compound crystallizes in triclinic,space group P1 with a = 12.137(2),b = 14.535(3),c = 14.894(3),α = 86.380(3),β = 70.381(3),γ = 72.647(3)°,V = 2360.3(8)3,C107H64Cl6Mn3N4O18,Mr = 2071.14,Dc = 1.457 g/cm3,μ(MoKα) = 0.638 mm-1,F(000) = 1055,Z = 1,the final R = 0.0638 and wR = 0.1905 for 6155 observed reflections(I > 2σ(I)).It exhibits a 3D supramolecular network through hydrogen bonding and π-π stacking interactions.     

Synthesis,Crystal Structure and Characterization of a New Coordination Polymer Based on Trinuclear Mn（Ⅱ） Cluster：[Mn3（L）2（adip）3]·2H2O

The coordination polymer,[Mn3(L) 2(adip) 3]·2H2O(L = 2-(4-fluorophenyl) -1H-imidazo[4,5-f] [1,10]phenanthroline and H2adip = adipic acid) ,has been synthesized under hydro-thermal conditions and characterized by elemental analysis,IR and single-crystal X-ray diffraction. It crystallizes in triclinic,space group P1 with a = 8.4085(11) ,b = 11.1273(14) ,c = 14.5758(18) ,α = 78.528(2) ,β = 75.425(2) ,γ = 78.143(2) °,V = 1276.0(3) 3,Z = 1,C56H50F2Mn3N8O14,Mr = 1261.86,Dc = 1.642 g/cm3,F(000) = 647,μ(MoKa) = 0.819 mm-1,R = 0.0446 and wR = 0.1008. The backbones of the two types of adip dianions link the neighboring trinuclear Mn(Ⅱ) clusters to yield a two-dimensional layer structure. The large conjugated L ligands are located on both sides of the two-dimensional layers. Additionally,the O-H···O,O-H···N and N-H···O hydrogen bonds further stabilize the structure.     

柔性二羧酸和双咪唑配体共同构筑的二重穿插的镍(Ⅱ)配位聚合物

本文报道了1个二重穿插的配位聚合物[Ni2(1,2-bix)2(oba)2(H2O)2],并对该化合物进行了元素分析、红外和单晶X-射线表征(1,2-bix=1,2-(二亚甲基苯)二咪唑配体,oba=4,4′-氧联苯二甲酸阴离子)。该化合物属于单斜晶系,空间群P21/n,晶胞参数a=1.475 3(5)nm,b=1.684 1(4)nm,c=2.135 6(5)nm,β=102.864(3)°,V=5.173(2)nm3,Z=4,R=0.040 5,wR=0.101 0。在该化合物中,oba和1,2-bix连接着Ni(Ⅱ)原子形成二维(4,4)网络结构。2个相邻的(4,4)网络相互穿插形成了二重穿插的二维层状结构。O-H…O氢键进一步地稳定了此层状结构。