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Polyaniline (PA) film was chemically deposited onto the surface of activated carbon (AC) uniformly. Chemical deposition was carried out in 0.1 mol/L aniline plus 0.5 mol/L H 2 SO 4 solution adopting V 2 O 5 •nH 2 O coated on the surface of activated carbon as oxidant. The surface morphologies and structures of the composite materials were characterized by scanning electron microscopy and FT-IR spectra. The electrochemical properties of the composite material electrodes were studied by cyclic voltammetry and constant current charge/discharge tests in 1 mol/L H 2 SO 4 solutions. The specific capacitance of composite materials was exhibited as high as 237.5 F/g at a current density of 1.0 A/g compared with a value of 120 F/g for pure carbon electrode. Good power characteristic and good stability of composite electrodes were also demonstrated.Keywords composite material, activated carbon, chemical deposition, polyaniline, electrochemical capacitor InctroductionElectrochemical capacitors attract growing attention to the use of electrical energy storage systems because of higher specific power than batteries and higher specific energy than conventional capacitors. The materials studied for capacitor applications have been mainly of three types: carbon, transition metal oxides 1 and conducting polymers.2,3 Of these, conducting polymerbased electrochemical capacitors attracted already more and more attention due to the combination of high capacitive energy density and low material cost, and wide studies on polypyrrole, 4 polythiophene 5 and polyaniline (PA) 6,7 have been reported. The conducting polymers, however, have disadvantages that include lower cycle-life and slow kinetics of ion transport because the redox sites in the polymer backbone are not sufficiently stable for many repeated redox processes. 8,9 Synthesis and investigation of electro-physical properties of polymer composites based on conductivity polymer and carbon materials, including nanotubes, 10 carbon fiber 11 and activated carbon (AC), 12 are currently very popular topics in the field of materials science and of theoretical and practical interest. For example, now nanotube/polymer composites are regarded as promising materials for use in lithium batteries, supercapacitors, sensors, etc.Activated carbon has more advantages than carbon nanotubes as a substrate to modified polymer for electrochemical capacitor due to its low cost and high surface area although the equivalent series resistance of the latter materials with better frequency responses is definitely smaller than that of the formers. 13 However, it is difficult to deposit polymer homogeneously onto the surface of activated carbon powders due to the surface structures. Hu 11 and Chen 12 have deposited PA onto AC and AC-fabric by electrochemical method and the products have a good electrochemical performance, but these methods are difficult to use for practical purposes.In this work, we describe a novel and simple method to chemically deposit PA onto the surface of AC powders uniformly adopting ...

Contextual mobile advertising, with the advantages of high interactivity and immersive experience, is the mainstream trend of future Internet advertising. Current studies have explored the benefits of contextual mobile advertising while lacking the analysis of contextual mobile advertising factors on consumer purchase intentions. This study investigates the mechanisms by which the characteristics of contextual mobile advertising evoke consumers' purchase intentions through advertising attitudes to reveal how extroversion and neuroticism in personal traits moderate the relationship between characteristics of contextual mobile advertising and advertising attitudes. Based on a sample of 543 community residents with mobile shopping experience in China, this study uses structural equation modeling to validate the relationships between the variables and draws conclusions. The findings help advertisers to grasp the important characteristics of contextual mobile advertising, improve consumers' attitudes toward advertising, and enhance purchase intentions. Furthermore, it is possible to expand perceptions of the effectiveness of contextual mobile advertising among consumers with different personality traits.

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