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Aromatic triazole chromophores were incorporated into polyfluorene in an attempt to increase electron affinity, to promote emission efficiency, and to diminish excimer formation. Poly(9,9‐dihexylfluorene) ( P1 ) and new copolymers with aromatic triazoles ( P2 – P4 ) were prepared by Suzuki coupling polymerization. In P2 , the aromatic triazole (3.8 mol %) was attached exclusively as terminal groups, whereas P3 and P4 were main‐chain copolymers containing 3.9 and 10.3 mol % aromatic triazole chromophores, respectively. The copolymers were soluble in common organic solvents and showed high decomposition temperatures (437–458 °C). The twisted structure between the triazole and fluorene increased the emission efficiency and effectively prevented excimer formation in P2 – P4 . After the introduction of the triazole units, the absorption spectra showed a blueshift (from 388 to 381 nm in chloroform) due to confined conjugation, but the photoluminescence spectra remained almost the same (417–418 nm); this was attributed to oligofluorene segments. No emission of triazole fluorophores was observed because of efficient energy transfer from the triazole to oligofluorene segments. However, incomplete energy transfer was observed in CH3COOH. The optical stability upon thermal annealing was also improved by the incorporation of aromatic triazole segments. From cyclic voltammetry results, P2 – P4 , containing triazole groups, showed greater electron affinity (lowest unoccupied molecular orbital level = ?2.67 to ?2.71 eV) than P1 (?2.52 eV). Electroluminescence devices of P1 – P4 all exhibited excimer emissions (483–521 nm), which could also be diminished by the introduction of aromatic triazole chromophores. © 2006Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 136–146, 2007  相似文献   
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A series of CuII metallo‐assemblies showing anion‐directed structural variations, including five metallocages [(Gn?)?{Cu2(Hdpma)4}](8?n)+(A?)8?n (Gn?=NO3?, ClO4?, SiF62?, BF4?, SO42?; A?=NO3?, ClO4?, BF4?, CH3SO4?; Hdpma=bis(3‐pyridylmethyl)ammonium cation), a complex double salt, namely, (H3dpma)4(CuCl4)5Cl2, and a coordination chain, namely, [Cu2(dpma)(OAc)4], are reported. The influence of the anion can be explained by its coordinating ability, the affinity of which for the CuII center interferes significantly with metallocage formation, and its shape, which offers host–guest recognition ability to engage in weak metal–anion coordination and hydrogen bonding to the organic ligand, which are responsible for metallocage templation. EPR studies of these metallocages in the powder phase at room temperature and 77 K showed a trend of the g values (g||>2.10>g>2.00) indicating a ‐based ground state with square‐pyramidal geometry for the CuII centers. The magnetism of these metallocages can be interpreted as the result of a combination of relatively small magnetic coupling integrals and a substantial contribution of temperature‐independent paramagnetism (TIP). The weak magnetic interaction is corroborated by the results of DFT calculations and the EPR spectra. Availability of the low‐lying state for spin population was confirmed by a magnetization study, which revealed a magnetic moment approaching 2, which would explain the presence of the larger TIP term.  相似文献   
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Three strains of Ganoderma tsugae (CCRC36065, CCRC37034, CCRC37038) and three strains of Ganoderma lucidum (CCRC36021, CCRC37029, CCRC37033) were cultivated. Their triterpenoid patterns of the fruit body were analyzed by reverse phase HPLC using a gradient elution of acetonitrile/2% acetic acid (1/4 and 1/2). The triterpenoid patterns of G. tsugae and G. lucidum are different. But similar 2 and 3 dimensional patterns are obtained among three strains of G. tsugae. Different patterns are found among different strains of G. lucidum. Ganoderic acid A( 1 ), B( 2 ), C( 3 ) and D( 4 ) were isolated from the ethanol extract of G. tsugae.  相似文献   
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The objective of this paper is to develop an inexpensive, robust, and precise scattered-type triangulation laser probe system with six linear charge-coupled devices (CCDs), that can be used to measure simultaneously the distance and inclination angle of a workpiece surface. The developed system has been configured and assembled based on Scheimpflug's principle. Through the specific arrangement of the six linear CCDs, four different measurement modules for the developed system were possible, namely the standard triangulation probe module, the double triangulation probe module, the pentagon-like triangulation probe module, and an approximately circular triangulation probe module. Angular measurements of an inclined surface were possible using the double triangulation probe module. The measuring range of the developed laser probe was ±2 mm and the resolution was 2 μm/pixel. The performance tests among the different measurement modules of the developed probe and the commercial circular triangulation laser probe OTM3-03 have been carried out. The measurement uncertainty of the developed laser probe system, with respect to different surface roughness and slope, was generally smaller than ±20 μm within the measuring range using the pentagon-like triangulation probe module with the statistical methodology of skewness (Sk) and kurtosis (Ku) analysis by setting the appropriate threshold values for Sk and Ku, respectively. The developed probe has been integrated with a PC-based 3-axis micro-positioning stage to construct an automatic non-contact 3D measurement system and to digitize the 3D profile of a small complex object.  相似文献   
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Electrodeposition method, a simple, cheap, and flexible approach, to fabricate gold nanoparticle (Au NPs) films with an area larger than 1 cm2 on indium tin oxide (ITO) electrodes modified with (3‐mercaptopropyl) trimethoxysilane (MPTMS) was presented. Size‐controllable and high loading Au NPs were obtained, which were characterized by field‐emission scanning electron microscopic (FESEM) and UV‐vis spectroscopy. Our current method provides a versatile and facile pathway to fabricate large‐scale metal nanoparticles thin film, enhancing alternatives for academic investigation and industrial application.  相似文献   
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Transparent yellow plates of rubidium manganese hexa­thio­diphosphate, Rb2MnP2S6, were synthesized in molten RbBr. The compound is isotypic to other compounds of the type A2MP2Q6 (A = K, Rb, Cs; M = Mn, Fe; Q = S, Se). Its structure can be viewed as columns of face‐sharing S6 polyhedra parallel to the a axis, interconnected by Rb+. The S6 polyhedra are centered alternately by Mn (in octahedral coordination) and P2 units (in trigonal antiprisms). The Mn atom and P2S6 group lie on centers of symmetry.  相似文献   
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