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991.
Catalytic membrane reactors which carry out separation and reaction in a single unit are expected to be a promising approach to achieve green and sustainable chemistry with less energy consumption and lower pollution. This article presents a review of the recent progress of dense ceramic catalytic membranes and membrane reactors, and their potential applications in energy and environmental areas. A basic knowledge of catalytic membranes and membrane reactors is first introduced briefly, followed by a short discussion on the membrane materials including their structures, composition and strategies for material development. The configuration of catalytic membranes, the design of membrane reaction processes and the high temperature sealing are also discussed. The performance of catalytic membrane reactors for energy and environmental applications are summarized and typical catalytic membrane reaction processes are presented and discussed. Finally, current challenges and difficulties related to the industrialization of dense ceramic membrane reactors are addressed and possible future research is also outlined. 相似文献
992.
In a free solution of 10.0 mM Gly-Gly (pH 8.2), the flow directions of native-DNA and DNA molecules intercalated with the fluorescent dye YOYO-1 were reversed in the microchip channel. These results clearly showed that in a confined space and under specific environmental conditions, the fluorescent dye modified the original properties and behavior of the native-DNA molecule. 相似文献
993.
Lee SK Cho JM Goo Y Shin WS Lee JC Lee WH Kang IN Shim HK Moon SJ 《Chemical communications (Cambridge, England)》2011,47(6):1791-1793
A highly processable, new semiconducting polymer, PCDTTz, based on alternating thiazolothiazole and carbazole units was synthesized. The new polymer exhibited a field-effect carrier mobility of up to 3.8 × 10(-3) cm(2) V(-1) s(-1) and bulk heterojunction solar cells made from PCDTTz produced a power conversion efficiency of 4.88% under AM 1.5 G (100 mW cm(-2)) conditions. 相似文献
994.
Murale DP Lee KM Kim K Churchill DG 《Chemical communications (Cambridge, England)》2011,47(46):12512-12514
A novel fluorescent difluoroboroazaoxobenzazulene dye has been synthesized from commercially available substrates in "one pot"; it was characterized structurally and spectroscopically, derivatized and finally compared to a related BODIPY system that demonstrates "turn-on" H(+) (42-fold) and F(-) (~5-fold) responses. 相似文献
995.
Graphite nanofibers (GNFs), on which surface graphite edges were reconstructed into nano-loops, were explored as a cathode catalyst support for fuel cells. The high degree of graphitization, as well as the surface-reconstructed nano-loops that possess topological defects for uniform metal deposition, resulted in an improved performance of the GNF-supported Pt catalyst. 相似文献
996.
Cho CH Kang H Kang TE Cho HH Yoon SC Jeon MK Kim BJ 《Chemical communications (Cambridge, England)》2011,47(12):3577-3579
A simple and efficient approach of controlling the side-chain density in the electron donating polymers has been demonstrated to tune their 3-D packing structure and HOMO level, which increases the hole mobility and V(oc) values, thus improving the solar cell performance. 相似文献
997.
Wang F Tan YX Yang H Zhang HX Kang Y Zhang J 《Chemical communications (Cambridge, England)》2011,47(20):5828-5830
Successful development of a new synthetic approach towards tetrahedral imidazolate frameworks (TIFs) via combining an auxiliary uninegative linker into the zinc-imidazolate tetrahedral assembly leads to new TIF materials (TIF-A1 to TIF-A3) with distinct structural topologies and high CO(2) uptake capacity. 相似文献
998.
Han L Zhang Y Kang J Tang J Zhang Y 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,82(1):146-152
In this paper, three kinds of imidazole derivatives, 2-(4-methylphenyl)-4,5-di(2-furyl) imidazole (MDFI), 2-(4-nitrophenyl)-4,5-di(2-furyl) imidazole (NDFI), and 2-(4-tert-butylphenyl)-4,5-di(2-furyl) imidazole (t-BDFI) were synthesized. In an alkaline medium, the chemiluminescence (CL) reaction of imidazole derivatives with H2O2 has been investigated. It was also found that MDFI/H2O2 and t-BDFI/H2O2 systems gave strong CL. When Co2+ was added into the two CL systems, the CL intensity was remarkably enhanced. In the optimum conditions, the CL intensity is linearly related to the logarithm of concentration of Co2+. The linear ranges are 5 × 10−9–2.5 × 10−7 mol/L for MDFI/H2O2 system and 5 × 10−9–2.5 × 10−7 mol/L for t-BDFI/H2O2 system, and the corresponding detection limits are 1.2 × 10−9 mol/L and 1.1 × 10−9 mol/L, respectively. The method was applied to the determination of Co2+ in vitamin B12 injection. Furthermore, the CL mechanism was also discussed. 相似文献
999.
Li2MnO3-based composite cathodes for lithium batteries: A novel synthesis approach and new structures 总被引:1,自引:0,他引:1
J.R. Croy S.-H. Kang M. Balasubramanian M.M. Thackeray 《Electrochemistry communications》2011,13(10):1063-1066
A new, simple technique has been demonstrated for fabricating high-capacity composite electrode structures. In this technique, Li2MnO3 is leached in acid in the presence of soluble transition metal ions and subsequently annealed between 450 and 850 °C. The technique can be used to prepare a wide variety of composite compounds, in particular, a new family of ‘layered–rocksalt’ xLi2MnO3·(1−x)MO (e.g., M = Ni and Co) structures and modifications thereof, as well as ‘layered–layered’ xLi2MnO3·(1−x)LiMO2 (e.g., M = Mn, Ni, and Co) and ‘layered–spinel’ xLi2MnO3·(1−x)LiM2O4 (e.g., M = Mn and Ni). This novel approach also holds promise for 1) synthesizing materials that reduce the extent of internal phase transitions of composite cathode structures with a high manganese content, and 2) minimizing the extent to which cells need to be electrochemically activated to remove Li2O, thereby reducing the extent of the irreversible capacity loss on the first charge/discharge cycle. 相似文献
1000.
Ling-Bin Kong Mao-Cheng Liu Jun-Wei Lang Min Liu Yong-Chun Luo Long Kang 《Journal of Solid State Electrochemistry》2011,15(3):571-577
A new porous cobalt hydroxide film has been successfully electrodeposited on nickel foam from 0.1?M cobalt nitrate electrolyte at ?1.0?V vs. SCE without adding any surfactant. The microstructure and surface morphology of prepared cobalt hydroxide films were physically characterized by X-ray diffraction analysis and scanning electron microscopy. The results indicate that an interlaced network structure was obtained. The effects of electrodeposition time, deposition potential, and different substrates on the specific capacitance and microstructure of prepared porous ??-Co(OH)2 thin film were systematically studied. The results indicate that the film deposited on nickel foam at ?1.0?V has excellent electrochemical properties. A maximum specific capacitance of 1473?F?g?1 could be achieved at a current density of 2?A?g?1. 相似文献