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21.
An unusual ceria dispersion was achieved by using the confined space between template and silica walls in as-prepared mesoporous silica, for the first time. The new adsorbents exhibit high adsorptive desulfurization activity and, more importantly, excellent stability and reusability, which is impossible to realize with conventional adsorbents.  相似文献   
22.
The reactions of SbCl3 and HgCl2 with 2-(3-pyridyl)benzimidazole (PyBIm) in solution acidified with HCl have been investigated. The PyBIm ligands are protonated into 2-(3-pyridinio)benzimidazolium (H2PyBIm) cations and the corresponding metal ions are bonded with chloride atoms into coordination anions, forming two new coordination compounds, namely, (H2PyBIm)(SbCl5) 1 and (H2PyBIm)2(Hg2Cl8) 2. Both compounds were characterized by X-ray crystallography. Crystal data for 1: triclinic, space group P1 with a = 5.7030(7), b = 9.0625(11), c = 16.5929(18) , α = 91.808(7), β = 93.234(6), γ = 99.216(7)o, C12H11N3SbCl5, Mr = 496.24, V = 844.44(17) 3, Z = 2, Dc = 1.952 g/cm3, μ(MoKα) = 2.419 mm-1, F(000) = 480, the final R = 0.0496 and wR = 0.1382 for 3433 observed reflections (I > 2σ(I)). Crystal data for 2: monoclinic, space group P21/c with a = 7.8061(5), b = 15.8127(9), c = 12.2435(9) , β = 91.955(4)o, C24H22N6Hg2Cl8, Mr = 1079.26, V = 1510.40(17) 3, Z = 2, Dc = 2.373 g/cm3, μ(MoKα) = 10.889 mm-1, F(000) = 1008, the final R = 0.0293 and wR = 0.0562 for 2854 observed reflections (I > 2σ(I)). X-ray diffraction analysis reveals that the antimony(III) is five-coordinated, exhibiting a slightly distorted square-pyramidal coordination geometry; while in 2, a dimeric [Hg2Cl8]4-anion consists of two trigonal bipyramids sharing two common edges. The organic cations and coordination anions are connected into a one-dimensional belt and a two-dimensional sheet through N-H···Cl hydrogen bonding interactions in compounds 1 and 2, respectively; both are further aggregated into 3D frameworks by strong π-π contacts.  相似文献   
23.
The reactions of Co(ClO4)2·6H2O and Co(NO3)2·6H2O with the di-Schiff base ligand N,N'-bis-(1-benzimidazo-2-yl-ethylidene)-ethane-1,2-diamine (LA) in ethanol have been investigated. The reactions of LA with excess amount of cobalt salts yield the six-coordinate complexes [CoL2](ClO4)2·H2O 1 and [CoL2](NO3)2·H2O 2 as isolatable products (L = N-(1-benzimidazo-2-yl-ethylidene)-ethane-1,2-diamine), where L is a tri-dentate mono-Schiff base ligand, resulting from the hydrolysis of the precursor di-Schiff base LA. Both complexes were characterized by X-ray crystallography. Crystal data for complex 1: monoclinic, space group P21/c, a = 11.9214(10), b = 23.5828(17), c = 14.0387(12) , β = 135.219(4)o, C22H30Cl2CoN8O9, Mr = 680.37, V = 2780.1(4) 3, Z = 4, Dc = 1.625 g/cm3, μ(MoKα) = 0.876 mm-1, F(000) = 1404, the final R = 0.0725 and wR = 0.1530 for 5726 observed reflections (I > 2σ(I)). Crystal data for complex 2: monoclinic, space group P21/c, a = 18.2162(16), b = 10.0610(6), c = 18.593(2) , β = 130.099(3)o, C22H30CoN10O7, Mr = 605.49, V = 2606.5(4) 3, Z = 4, Dc = 1.543 g/cm3, μ(MoKα) = 0.722 mm-1, F(000) = 1260, the final R = 0.0619 and wR = 0.1429 for 5194 observed reflections (I > 2σ(I)). X-ray diffraction analysis reveals that each cobalt atom in the two complexes is chelated by six nitrogen atoms from two tridentate ligands L, exhibiting a slightly distorted octahedral coordination sphere. In both complexes, the strong hydrogen-bonding interactions between the lattice waters and N-H groups of the ligands result in 1D chains which are further connected by ClO4-(or NO3-) groups to form a 3D framework. In complex 2, the strong π-π interactions increase the stability of the structure.  相似文献   
24.
The one-dimensional double helicate, [NH4][Mo2O4Gd(H2O)6(L-C4H2O6)2] x 4H2O (1), which was synthesized by the reaction of GdCl3, L-tartaric acid and ammonium molybdate in acidified water solution, is built up by two heft-handed single-helical chains, linked up further by eight-coordinated GdIII pieces in an enantiopure left-handed double helical configuration, of which each helix is formed by L-tartrate bridged six-coordinated MoVI atoms.  相似文献   
25.
Sm(Ⅲ)(MTB)2配合物与DNA作用的光谱法研究   总被引:2,自引:0,他引:2  
The interaction between Sm(Ⅲ)(MTB)2 complex and Herring Sperm DNA has been studied by UV-Vis spectral, Fluorescence spectral in buffer solution of Tris-HCl (pH=7.25) using Neutral Red (NR) as a probe. The intercalation and electrostatic manner are confirmed to be the two major modes for interaction between Sm(Ⅲ)(MTB)2 complex and Herring Sperm DNA. The balance constant of Sm(Ⅲ)(MTB)2 rare earth metal complex and Herring Sperm DNA is K=4.10 × 104 L·mol-1. The results indicate that biological functions of Herring Sperm DNA are changed to a certain extend due to the interaction between Sm(Ⅲ)(MTB)2 rare earth metal complex and Herring Sperm DNA.  相似文献   
26.
采用NaHCO3与FeCl3?6H2O,ZnSO4?7H2O,Co(NO3)2?6H2O和Sm(NO3)3?6H2O进行室温固相反应制得碱式碳酸盐和氢氧化铁混合前驱物,先微波加热,再热分解分别制得复合氧化物ZnFe2O4,Co0.5Zn0.5Fe2O4和Co0.5Zn0.5Fe1.95-Sm0.05O4.由激光粒度分析仪、XRD和SEM表征:获得了颗粒分布均匀、平均粒度为62nm左右的立方晶系尖晶石结构的纳米铁氧体粉体.并测试样品的相对介电常数和相对磁导率,研究了它们的电磁损耗特性.结果表明:在ZnFe2O4中,掺入Co2 ,Sm3 元素可以在100~1800MHz测试频率范围内不同程度提高材料的电磁损耗特性.  相似文献   
27.
The title compound (Mo4XS15P6O12C24H30), α-Mo4XS3(μ-dtp)3(dtp)3 (X=0.6S+0.4O; dtp=-S2P[OEt]2), isolated as a prismatic black crystal, was prepared from ethanolic solution of Mo(CO)6, MoCl5 and P2S5. It crystallizes in triclinic system, space group P with a=14.031(4), b=13.372(2), c=16.270(8)(A), α=92.15(2), β = 72.91(3), γ = 95.20(2)°, V = 2905.4(2)(A)3, Z = 2, Dc = 1.82 g/cm3, Mr=1598.93, F(000)=1564.8, λ=0.71069(A)(MoKα), μ=1.584 mm-1. The final R=0.058, Rw=0.057 for 5016 observed reflections with I≥3.0σ(I). The structure analysis reveals that the title compound has a [Mo4XS3] core, belonging to the cubane-type tetranuclear molybdenum clusters family, with one of its four μ3-caps being statistically occupied by S and O. Three dtp ligands chelated three μ-X capped Mo atoms as terminal ligands, while another three dtp bridged these three Mo atoms and the fourth one, forming an α-type cluster compound.  相似文献   
28.
吴鼎铭  黄小荥 《结构化学》1994,13(5):385-388
SynthesisandStructureof[HOCH_2CH_2N(CH_3)_3]_4[Cu_4OCl_(10)]WuDing-Ming;HuangXiao-Ying;ZhuangHong-Hui(StateKeyLaboratoryofStruct?..  相似文献   
29.
The title complex, Cd(MeHbibzim)(1,4-bdc)n (1, MeHbibzim = 1-methyl-2,2'- bibenzimidazole, 1,4-bdc = terephthalate), was synthesized with hydrothermal reactions. The compound crystallizes in monoclinic, space group C2/c with a = 9.822(4), b = 18.510(7), c = 22.372(9), β = 98.359(6)°, C23H16CdN4O4 , Mr = 524.81, V = 4024(3)3 , Z = 8, Dc = 1.733 g/cm3 , μ(MoKα) = 1.126 mm-1 , F(000) = 2096, the final R = 0.0597 and wR = 0.1374 for 3906 observed reflections (Ⅰ > 2σ(Ⅰ)). X-ray diffraction analysis reveals that the Cd atom is coordinated by two nitrogen atoms from the chelating MeHbibzim and three carboxyl oxygen atoms from three terephthalate ligands, thus forming a distorted square pyramidal coordination sphere, CdN2O3. Every two Cd atoms are linked together via two carboxyl groups into a dinuclear unit with Cd···Cd separation of 3.806(4). The dinuclear building units are linked by terephthalate ligands into two-dimensional layers, which are further aggregated into a 3D framework via hydrogen bonding interactions.  相似文献   
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