Self-flux-grown Ba4Fe4ClO9.5-x crystals exhibiting structures with tunable modulation.

The synthesis and X-ray structural study of the new family of compounds Ba4Fe4ClO9.5-x with tunable structural modulation are reported. The framework of the structure has the Ba2Fe4O9.5-x composition, with open hexagonal channels extending along the c-axis. The channels are filled with linear [Ba-Cl-Ba] triplets. The oxygen stoichiometry and the oxidation state of iron both are controlled by the redox conditions during crystal preparation. The modulation of the crystal structure arises from the distribution of the oxygen atoms in the framework and iron coordination polyhedra are a combination of FeO4-tetrahedra, FeO5-bipyramids, and FeO6-octahedra. The structure modulation also originates from the ordered or disordered distribution of the [Ba-Cl-Ba] triplets filling the channels which is also affected by the conditions of the thermal treatment of the crystals. The structure investigation reveals a composition variation from Ba4Fe4ClO9.5 (x = 0), in which Fe exhibits a 3+ oxidation state, to Ba4Fe4ClO8 (x = 1.5) with the framework built exclusively of FeO4 tetrahedra.

[Restoration of erectile function by reconstructing cavernous nerves with small intestinal submucosa grafts].

OBJECTIVE: To investigate the restoration of erectile function by reconstructing cavernous nerves (CN) with small intestinal submucosa (SIS) grafts. METHODS: We prepared SIS grafts, established rat models and divided the models into a CN ablation, a sham-operation and an SIS graft group. The CNs at both sides were severed with 1 cm ablated in the first group, and 0.5 cm removed in the third, followed by reconstruction with the SIS grafts. Three months after surgery, the apomorphine test was performed to evaluate the erectile function, and then all the rats were sacrificed to detect the expression of nNOS in the penis. RESULTS: Penile erection was observed in 72.73% (8/11) of the rats for (1.07 +/- 0.89) times within 30 min in the SIS graft group, as compared with 0% (0/11) of the rats for (0.00 +/- 0.00) times in the CN ablation group (P < 0.01), and 90.91% (10/11) of the rats for (2.19 +/- 1.17) times in the sham-operation group (P < 0.01). The number of nNOS nerve fibers was significantly larger in the SIS graft than in the CN ablation group (70.36 +/- 10.09 versus 22.09 +/- 4.76, P < 0.01), but both were significantly smaller than that of the sham-operation group (90.81 +/- 5.69, P < 0.01). CONCLUSION: The SIS grafting technique contributes to the recanalization of the severed CN and restoration of erectile function in rats after surgical injury.

Lanthanide coordination polymers constructed from infinite rod-shaped secondary building units and flexible ligands.

Three lanthanide coordination polymers constructed from infinite rod-shaped secondary building units (SBUs), [Nd(2)(H(2)O)(2)(cis-chdc)(2)(trans-chdc)]2H(2)O (1), Nd(2)(H(2)O)(4)(trans-chdc)(3) (2), and [Sm(2)(H(2)O)(2)(cis-chdc)(trans-chdc)(2)]4H(2)O (3) (chdcH(2)=1,4-cyclohexanedicarboxylic acid), were hydrothermally synthesized and structurally characterized. The structures of 1-3 are modulated by different ratios of the cis and trans configurations of chdc(2-) ligands, which was achieved by temperature control in the hydrothermal reactions. Crystal-structure analysis revealed that 1 is a four-connected pcu-type rod packing network built from cross-linking of rod-shaped neodymium-oxygen SBUs by cis- and trans-chdc(2-) ligands in a 2:1 ratio, 2 displays a complicated six-connected hex-type rod packing structure built by connection of rod-shaped neodymium-oxygen SBUs and trans-chdc(2-) ligands, and 3 features an unprecedented five-connected rod packing pattern constructed from rod-shaped samarium-oxygen SBUs and cis- and trans-chdc(2-) ligands in a 1:2 ratio.

A new chain-like cadmium(II) coordination polymer containing chains of water molecules.

The title cadmium(II) polymer, catena-poly[[[bis(4-aminopyridine-kappaN)aquacadmium(II)]-mu-1,4-phenylenediacetato-kappa(4)O,O':O'',O'''] dihydrate], {[Cd(C10H8O4)(C5H6N2)2(H2O)].2H2O}n, comprises one-dimensional wave-like chains, in which the Cd atom is coordinated by 1,4-phenylenediacetate and 4-aminopyridine molecules. The 1,4-phenylenediacetate ligands lie about inversion centres. Extensive hydrogen-bonding interactions between the chains lead to a three-dimensional structure. Free water molecules form chains in the structure.

A novel three-dimensional supramolecular coordination polymer: poly[[diaquadicadmium(II)-di-mu2-4,4'-bipyridyl-di-mu2-2-sulfonatobenzoato] dihydrate].

The hydrothermal reaction of Cd(CH3COO)2.2H2O, 4,4'-bipyridyl and 2-sulfobenzoic acid produced the title compound, {[Cd2(C7H4O5S)2(C10H8N2)2(H2O)2].2H2O}n, which forms a two-dimensional coordination polymer, the sheets of which are linked via hydrogen bonds. Two different types of Cd atoms are present, one lying on a twofold rotation axis and the other on a centre of inversion. Similarly, there are two types of bipyridyl ligand present, one lying across a twofold rotation axis and the other across a centre of inversion.

trans-Diaquabis(5-carboxy-1H-imidazole-4-carboxylato-kappa2N3,O4)cobalt(II) 4,4'-bipyridine solvate.

In the title compound, [Co(C(5)H(3)N(2)O(4))(2)(H(2)O)(2)].C(10)H(8)N(2), the Co atom is trans-coordinated by two pairs of N and O atoms from two monoanionic 4,5-dicarboxyimidazole ligands, and by two O atoms from two coordinated water molecules, in a distorted octahedral geometry. The 4,4'-bipyridine solvent molecule is not involved in coordination but is linked by an N-H...N hydrogen bond to the neutral [Co(C(5)H(3)N(2)O(4))(2)(H(2)O)(2)] molecule. Both molecules are located on inversion centers. The crystal packing is stabilized by N-H...N and O-H...O hydrogen bonds, which produce a three-dimensional hydrogen-bonded network. Offset pi-pi stacking interactions between the pyridine rings of adjacent 4,4'-bipyridine molecules were observed, with a face-to-face distance of 3.345 (1) angstroms.