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971.
DU Kang-Kai 《结构化学》2012,31(12)
A two-dimensional lead complex, [Pb(C14N3O2H12S)(NO3)]n·nH2O, was prepared by the reaction of salicylyl-4-phenyl thiosemicarbazide and lead nitrate. The compound (C14H13N4O6PbS, Mr=572.53) crystallizes in the monoclinic space group P21/c with a=11.2984(2), b=15.6628(7), c=11.1118(2), β= 113.564(2)n, V=1802.43(10)3, Dc=2.110 g/cm3, Z=4, μ(MoKα)= 9.515 mm·1, F(000)=1084, the final R=0.0394 and wR=0.0701 for 2552 observed reflections with I > 2σ(I). The Pb(II) ion displays a distorted octahedron in which the hypothesized stereochemically active lone pair occupies the apex. The compound exhibits a two-dimensional network structure formed by the zigzag one-dimensional chains joined by two μ-O of two nitrate groups in overlapping. A large ring exists in the two-dimensional layers. The TGA of the title compound has been studied. 相似文献
972.
采用溶胶-凝胶工艺先制备了Mn,Ca,Fe,Eu,O的化合物的凝胶,并用马弗炉对凝胶进行中温烧结.研磨成粉末,测量其XRD,结果表明,不同的配比,形成的晶体结构不同.铕钙铁锰按1:1:1:1和1:2:1:2的配比做出来的晶体结构较好. 相似文献
973.
研究了能级结构分别为Λ型三能级和V型三能级结构的两个原子和通过光纤耦合的由双模腔构成的复合系统中光场的压缩效应、二阶相干度和亚泊松分布等量子特性。利用数值计算方法讨论了光纤模与腔场间的耦合强度对量子特性的影响。研究结果表明:双模光场不呈现压缩效应,但呈现出反关联和亚泊松分布的量子特性;随着光纤模与腔场间耦合强度的增强,亚泊松分布减弱。 相似文献
974.
975.
在一台增压中冷的电控单体泵柴油机上采用柴油/甲醇组合燃烧(DMCC)方式进行排放特性与经济性试验研究。结果表明:采用DMCC方式能够大量减少NOx排放,同时CO2排放也有所降低。可以通过在排气管上加装氧化催化转换器(DOC)很好地清除掉DMCC方式增加的HC和CO排放,其催化效率在90%以上,比原机排放低很多,DMCC方式的甲醛排放比原机高,DOC对其催化率达98%,接近超低排放。DMCC模式外特性的热效率提高了7.607%,且存在一个最佳燃料匹配区间。 相似文献
976.
《Journal of Coordination Chemistry》2012,65(4):728-736
Two new compounds, [CuCl(Phen)(H2O)][PW12O40][4,4′-H2bpy]·1.5H2O (1) and [Cd2(Phen)4Cl2][HPMo12O40](4,4′-bpy) (2) (bpy?=?bipyridine, Phen?=?phenanthroline), have been hydrothermally prepared and characterized by IR, UV–vis, XPS, XRD, elemental analysis, cyclic voltammetry analysis, and single-crystal X-ray diffraction analysis. Compound 1 exhibits a 1-D chain structure constructed from polyoxometalates (POMs) and transition metal complexes, whereas 2 presents a supramolecular structure constructed from POMs, metal halide clusters, and organic ligands. 相似文献
977.
《Journal of Coordination Chemistry》2012,65(10):1671-1682
AbstractNanoparticles of a new mercury(II) coordination supramolecular compound (CSC), [{(Ar-Cl)tetra-azo-S}2Hg] (1), were synthesized using a sonochemical process and characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and elemental analyses (EA). The single crystal X-ray data of 1 revealed that the Hg ion was two-coordinate. Also, Hirshfeld surface analysis of 1 showed the effective role of interactions related to nitrogen atoms in stabilization of the supramolecular structure. The role of ultrasonic power, sonicating time and temperature on the size and morphology of the nano-structured compound obtained from 1 were investigated. The results indicated that increasing temperature and sonication power and decreasing sonication time led to reducing the particle size. 相似文献
978.
《Journal of Coordination Chemistry》2012,65(19):3180-3188
Three new energetic compounds, nickel(II) 3,5-dinitro-2-pyridonate (Ni(2DNPO)2(H2O)4, 1), copper(II) 3,5-dinitro-4-pyridonate (Cu(4DNPO)2(H2O)4, 2) and cobalt(II) 3,5-dinitro-4-pyridone-N-hydroxylate ([Co(4DNPOH)2(H2O)4] · 2DMF, 3 · 2DMF), were characterized by elemental analysis, FT–IR, TG-DSC and X-ray single crystal diffraction analysis. Complexes 1 and 2 are similar in structure with the metal ion coordinated by oxygen donors of four water molecules on the equatorial position and two nitrogen donors of the pyridone rings of two ligands in the axial positions. The cobalt(II) complex 3 · 2DMF is a heavily distorted octahedral geometry. The Co(II) has equatorial positions defined by oxygens of four water molecules. Its axial positions are filled with two oxygen atoms of the pyridone-N-hydroxylate of two ligands. The TG-DSC results reveal that 1 is the most stable, with higher initial thermal decomposition temperature and enthalpy. Based on the thermoanalyses, the nickel compound is a promising candidate as a component in catalyzed RDX-CMDB propellants in comparison with our earlier lead(II) analogs. 相似文献
979.
《Journal of Coordination Chemistry》2012,65(15):1703-1710
Two compounds of disphosphopentamolybdate(VI) with the formulae (C4H14N2O)3- [P2Mo5O23]?·?3H2O (1) and (C4H14N2O)5(NH4)2[P2Mo5O23]2?·?5H2O (2) have been synthesized by a simple, fast and efficient microwave method, and their crystal structures and spectroscopic properties have been studied. The heteropoly anion [P2Mo5O23]6? has a known structure built of five MoO6 octahedra and two PO4 tetrahedra. The MoO6 octahedra form a pentagonal ring by sharing four edges and one corner and the PO4 tetrahedra are attached to one side of the ring by three oxygen atoms. The most interesting feature of compound 1 is its extensive framework based on a one-dimensional zigzag chain. In compound 2, a more extensive and complicated framework of hydrogen bonds joins the anions, organic cations and water molecules together. 相似文献
980.
《Journal of Coordination Chemistry》2012,65(14):2516-2528
Four inorganic–organic hybrid compounds, [M2(CuL)4(V4O12)]·2H2O (M?=?Co (1), Mn (2)), [Mn2(NiL)4(V4O12)]·2H2O (3), and [Zn2(CuL)4(V4O12)]·2CH3OH·2H2O (4) (M′L, H2L?=?2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien), have been synthesized and characterized by elemental analysis, IR, UV, fluorescence spectra, and X-ray diffraction analysis. Single-crystal X-ray analysis reveal that both [V4O12]4? and M2V4 adapt a chair-like configuration in four structures. The cyclovanadate group [V4O12]4? is a tetradentate bridging ligand linking two [M(M′L)2]2+ fragments, producing centroantisymmetric heterometallic hexanuclear [M2M′4] complexes. The variable-temperature magnetic susceptibility measurements (2–300?K) of 1 and 2 show weak antiferromagnetic interactions. 相似文献