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H10O20P4Co3.14Cd1.86, monoclinic, C2/c (no. 15), a = 17.5779(6) Å, b = 9.0747(3) Å, c = 9.4946(3) Å, β = 96.636(3)°, V = 1504.38(9) Å3, Z = 1, R gt (F) = 0.0273, wR ref (F 2) = 0.0646, T = 293(2) K.

Peanut shell-derived porous carbon has been prepared by the KOH-assisted hydrothermal treatment and subsequent carbonization route. The influences of KOH concentrations on structure of resulting carbon are clearly studied. At a KOH concentration of 5 M, the obtained porous carbon, possessing inner micropores and surface macropores, has a specific surface area of 827.7 m2/g and moderate porous size. The amorphous Se is uniformly encapsulated into its microporous structure to form hierarchical porous carbon/selenium composite. As the cathode material of Li ion battery, this composite delivers an initial discharge capacity of 590.6 mA h/g with Coulombic efficiency of 71.6% at 0.2 C, and a high capacity retention ratio of 83.3% can be reached after 500 cycles at 2 C. Even at a high rate of 4 C, this composite still presents a discharge capacity of 405.8 mA h/g. By comparison, these improved electrochemical performances may be attributed to the hierarchical porous feature, moderate porous size and effective encapsulation of selenium.

Using hydrated manganese sulfate and general type graphene (GR) as raw materials, Mn3O4/GR composite has been successfully prepared by the liquid phase chemical co-precipitation method at room temperature. X-ray diffraction (XRD) was used to investigate the phase structure of Mn3O4powder and Mn3O4/GR composite; The electrochemical performances of the samples were elucidated by cyclic voltammetry and galvanostatic charge-discharge test in 0.5 mol/L Na2SO4electrolyte. The results show that the Mn3O4/GR composite possesses graphene phase and good reversibility; the composite also displays a specific capacitance of 318.8 F/g at a current density of 1 A/g.

A phytochemical investigation on the MeOH extract of the red alga Laurencia composita Yamada led to the discovery of six new highly halogenated sesquiterpenoids, including two bisabolane-type sesquiterpenoids (1 and 2), one nerolidol derivative (7), and three chamigrane-type sesquiterpenoids (9, 10, and 18), together with 13 known sesquiterpenoids. Their structures, including relative configuration, were elucidated by extensive spectroscopic analysis, and by comparison with data for related known compounds. The absolute configuration at C-10 of laurecomposin A (1) was determined by the modified Mosher's method. Halonerolidol (7) is the first naturally occurring halogenated nerolidol derivative, while compositacin L (9) represents the third example of chamigranes having a C-10 carbonyl group. Antifungal, antibacterial, and receptor tyrosine kinase inhibitory activities of these isolates were evaluated. The results showed that compounds 1–3 and 5 exhibited significant antifungal activity against Microsporum gypseum (Cmccfmza) with MIC values of 4, 8, 8, and 4 μg/mL, respectively. Additionally, compounds 1–3 and 5 also displayed promising antibacterial activity against Gram-positive bacteria Staphylococcus aureus Newman strain with MIC values ranging from 10.9 to 26.8 μg/mL.

The Co-Ni mixed oxides/graphene composite has been prepared using the solution based oxidation route. The structures of bare Co-Ni mixed oxides and Co-Ni mixed oxides/graphene composite is clearly studied by X-ray diffraction. The electrochemical properties of Co-Ni mixed oxides/graphene composite are investigated by Cyclic Voltammetry (CV) and galvanostatic charge discharge test. The result shows that, the NiO phase has not been detected in the composite, and the graphene composite delivers a discharge capacity of 353.6 F/g at a current density of 0.32 A g-1.

The blend cathode materials LiMn2O4/Li1.2(Mn0.56Ni0.16Co0.08)O2 have been successfully prepared by the physical mixing of commercial Li2MnO4 and self-prepared Li1.2(Mn0.56Ni0.16Co0.08)O2 nanoparticles. The structures, morphologies and electrochemical performances are characterized by X-ray diffraction (XRD), Scanning electron microscope (SEM), Cyclic Voltammetry (CV) and charge-discharge test, and the results show that the good mass ratio of Li2MnO4 and Li1.2(Mn0.56Ni0.16Co0.08)O2 is 50:50. Therein, the nanosized Li1.2Ni0.16Co0.08Mn0.56O2 uniformly adhere on the surface of Li2MnO4 micro structure, and occupy the gap of Li2MnO4 particles, which can effectively elevate the tap density of Li1.2(Mn0.56Ni0.16Co0.08)O2 nanoparticles. As lithium ion battery cathode, the 50:50 sample reveals an initial discharge capacity of 265.4 mAh/g with negligible irreversible capacity loss at current density of 0.1C within 2.0-4.8 V, and retain 89.2% after 20 cycles.

A promising Co 3 O 4 /CuO composite electrode material was successfully synthesized through a facile hydrothermal and calcination process. Effects of the surfactants hexadecyltrimethyl ammonium bromide (CTAB) and polyvinylpyrrolidone (PVP) on the morphology and electrochemical performance of the composite were investigated. Powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen adsorption-desorption experiment were employed to characterize the microstructures and morphologies of the composite. Meanwhile, the electrochemical performances of the samples were studied using cyclic voltammetry (CV), galvanostatic charge-discharge test and electrochemical impedance spectroscopy (EIS). The results show that the porous Co 3 O 4 /CuO-CTAB nanoplates own the best performance and exhibits a high specific capacitance of 398 F/g at 1 A/g with almost 100% capacitance retention over 2000 cycles, and it retains 90% of capacitance at 10 A/g.

A mixed-valence Keggin-structural 12-molybdophosphoric acid hydrate, NH4(C4N2H12)(C2N2H10)2 [Mo 4 V Mo 8 VI PO40]·2H2O (1), has been synthesized hydrothermally and characterized by single-crystal X-ray diffraction, elemental analysis, TG, XRD, IR, Raman, UV–Vis diffuse reflection spectrum and XPS spectrum. The compound 1 crystallizes in the monoclinic system with cell parameters of a = 20.668(4) A, b = 10.827(2) A, c = 21.508(4) A, β = 117.070(3)°, V = 4,285.6(14) A3, and space group C 2/c, Z = 4 at 293 K. The final full-matrix least-squares refinement converged to R 1 = 0.029 for the observed reflections (4,721) with I > 2σ(I) and wR 2 = 0.065 for all data (4,837) and S = 1.048. Compared with another compound, (C4N2H12)(C2N2H10)2[Mo5P2O23] (2) (Chen et al., Chin J Struct Chem 30:1178, 2011), compound 1 was obtained via only changing molar ratio of reactants and the pH value of reaction system. Meanwhile, compound 1 contains the same two kinds of organonitrogen ligands, even their molar ratio, but entirely different space architecture and distinct heteropoly blue building block, [Mo 4 V Mo 8 VI PO40]7−. The crystal packing of 1 presents interesting 1D Zig-zag, 2D laminated and even 3D honeycomb-like configurations.

National Natural Science Foundation of China [40472027, 40972035, 21233004]; Technological Innovation Platform of Fujian Province [2006L2003]; Natural Science and Engineering Research Council of Canada

A new approach to the synthesis of α, β-unsaturated ketones from 1,2,3-trimethyl benzimidazolium salt via the condensation reaction with aldehydes followed by the addition reaction of Grignard reagents with quaternary C=N bond was provided.

Using CH3SiCl3 (MTS) and H2 as the precursors, large quantities of SiC nanowires with homogeneous diameter have been fabricated by a simple chemical vapor deposition process without using a metallic catalyst. The as-grown SiC nanowires were identified by TEM and XRD as single crystal β-SiC structure, with diameters of about 70 nm. As the increasing of deposition temperature, or as the decreasing of H2/MTS mol ratio, the SiC crystal dimensions increase and the morphologies of the as-grown SiC crystal change from nanowires to grains. β-SiC coaxial nanocables with a amorphous wrapping layer have also been obtained by the oxidation of SiC nanowires.