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Studies on one‐dimensional polyanilines prepared with n‐dodecylbenzenesulfonic and camphorsulfonic acids 下载免费PDF全文
Yen‐Zen Wang Ming‐Jer Tsai Tar‐Hwa Hsieh Po‐Hao Tseng Chung‐Yi Lu Ko‐Shan Ho 《Polymer International》2015,64(11):1568-1577
Anilinium salts complexed with n‐dodecylbenzenesulfonic acid (DBSA) and camphorsulfonic acid (CSA) were found to self‐assemble into cylindrical micelles with bigger diameters than those complexed with only DBSA or CSA. These cylindrical micelles were polymerized into one‐dimensional copolyaniline nanotubes (PANIDBSACSA) via emulsion polymerization, demonstrating various morphologies depending on the ratio of DBSA to CSA. The UV?visible?NIR spectra of neat PANICSA and PANIDBSACSAs illustrate significant free carrier tails in the NIR region and conductivity 10–20 times higher than that of neat PANIDBSA whose UV?visible?NIR spectrum does not illustrate significant carrier tails. When the number of moles of DBSA is equivalent to or exceeds that of CSA in the polymerization mixture, SEM and TEM micrographs of the PANIDBSACSAs reveal that they have larger diameters than that of neat PANIDBSA. Besides, some of the surfaces of the big nanotubes were implanted and mounted with lots of small nanofibers of neat PANICSA polymerized from some of the CSA‐complexed aniliniums which were excluded from the cylindrical micelles before polymerization. TGA thermograms of PANIDBSACSAs show an intimate relationship between thermal deprotonation and the DBSA to CSA ratio. X‐ray diffraction patterns demonstrate a layered structure arrangement of polyaniline molecules of all one‐dimensional nanofibers. © 2015 Society of Chemical Industry 相似文献
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针对软土地区单桩静载试验中常用的基准梁百分表沉降量测系统易受压重平台影响的问题,提出将精密水准仪作为静载试验的沉降量测系统。并通过两个观测系统的对比试验,证明了精密水准仪沉降量测系统的优点和实用价值。 相似文献
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Liliana Martelo Alfonso Jiménez Artur JM Valente Hugh D Burrows Ana T Marques Michael Forster Ullrich Scherf Mercedes Peltzer Sofia M Fonseca 《Polymer International》2012,61(6):1023-1030
Films of neat and plasticized biodegradable poly(lactic acid) (PLA) matrices containing anionic conjugated polyelectrolytes, poly[9,9‐bis(4‐phenoxybutylsulfonate)]fluorene‐2,7‐diyl‐alt‐arylenes, with 1,4‐phenylene and 4,4″‐p‐terphenylene, respectively, as arylene groups or a neutral poly(9,9‐dialkylfluorene) for comparison were prepared by solution casting. These films were characterized using differential scanning calorimetry, thermogravimetry, scanning electron microscopy and fluorescence spectroscopy. In addition, the effects of plasticizer on the thermal properties and the oxygen permeability of the PLA films were measured through the oxygen transmission rate. Results show that it is possible to obtain thin, optically transparent and luminescent films with potential in oxygen sensing, exhibiting good thermal and photochemical stability. At high polyelectrolyte content, evidence is found for phase separation and aggregate formation and it is no longer possible to obtain completely homogeneous films. The possibility of incorporating the cationic metal complex tris(2,2′‐bipyridyl)ruthenium(II) into plasticized PLA films containing conjugated polyelectrolytes for dual‐wavelength ratiometric luminescence sensing is also discussed. Copyright © 2012 Society of Chemical Industry 相似文献
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Abstract In this paper, a novel detuning index is first proposed for indicating the proper timing required to correct the rotor time constant of indirect rotor flux oriented controlled single‐cage induction motor drives. This index can faithfully reflect the influence of rotor resistance changes as well as rotor flux changes. It also reduces greatly the number of rotor time constant estimations in practical applications. The theoretical basis of the index and the physical meaning are described in the paper in detail. Based on the proposed index, an on‐line rotor time constant estimator is also proposed to make corrections. Only existing available quantities of the closed loop controller are used for calculating the estimated rotor time constant accurately. Both simulation and experimental results verify the effectiveness of the proposed rotor flux orientation technique. It is seen that the proposed rotor flux orientation technique is suitable for practical applications. 相似文献
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We report here preparation and characterization of an AuCu3 alloy electrochemical sensing platform fabricated on an easy for mass production barrel-plated gold electrode (AuBPE). Note that the AuBPE consists of Cu main body with successive plating of a very thin layer of Ni and Au (i.e., Cu–Ni–Au multilayer). By suitably manipulating the grain boundary diffusion between individual metallic layers of Cu–Ni–Au by means of thermal annealing treatment, AuCu3 alloy film can be formed directly on the outer surface of the AuBPE. Electrochemical activation in alkaline solution can further generate a nanostructured AuCu3 alloy film. This facile and novel approach is promising to prepare sensors for electroanalytical applications, e.g., glucose oxidation in pH-neutral solutions and simultaneous detection of uric acid, dopamine and ascorbic acid. 相似文献
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Ting-Hao Yang Shanmuganathan Venkatesan Chien-Hung Lien Jen-Lin Chang Jyh-Myng Zen 《Electrochimica acta》2011,(17):6205
In this study, we report the application of an inexpensive and easily prepared lead oxide–manganese oxide catalyst combined with Nafion (designated as Nf/PbMnOx) as a highly efficient air-cathode for a zinc–air battery. We verify the mechanistic study of the reduction of O2 for Nf/PbMnOx in alkaline aqueous solution using rotating ring/disk electrode voltammetry, and also an electrochemical approach using a wall-jet screen-printed ring disk electrode. The presence of Nf/PbMnOx shows great catalytic activity for the disproportionation reaction of HO2− to O2 and OH− with an overall 4e− reduction of O2 in the first reduction reaction. The 4e− reduction of O2 was eventually achieved at the Nf/PbMnOx through evidence from the slope of Koutecky–Levich plots. With these inherent features, we then fabricated the zinc–air battery with the Nf/PbMnOx catalyst and examine the performance for a practical application with air cathodes. 相似文献
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Although polymer blend nanocomposites are widely studied, the balance between stiffness and toughness has not yet been investigated in detail. Some materials producers as well as some sectors in the automotive industry try to improve the toughness of materials without an important loss in stiffness. With this in mind, the aim of the study reported here was to obtain a good balance between toughness and stiffness of polymer blends with different amounts of clay and compatibilizer. In this context, the microstructure of polyamide 6/ethylene–propylene–diene metallocene terpolymer/(ethylene–propylene–diene copolymer)‐graft‐(maleic anhydride) blends with various amounts of clay (2, 3, 4 and 5 wt%) and compatibilizer (10 and 20 wt%) was studied to analyse the achieved morphology to understand the macroscopic properties. The morphology of the rubber phase and the dispersion of the montmorillonite (MMT) are the main factors that influence the mechanical properties. In this sense, the highest Young's modulus is achieved for nanoblends with 5 wt% of MMT, although this nanoblend has the lowest value of notched Izod impact strength. The results obtained suggest that there is a clear trade‐off between stiffness, toughness and temperature behaviour when the ratio of (ethylene–propylene–diene copolymer)‐graft‐(maleic anhydride) to MMT is 5:1. Copyright © 2009 Society of Chemical Industry 相似文献