6,473 research outputs found

    Applications of nanostructured materials and biomolecules for electrocatalysis and biosensors

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    Electronically conducting polymers are important materials, and composites of these materials with metal nanoparticles have also been drawn significant research attention in recent years. We prepared a highly stable Agnano-Poly (3, 4-ethylenedioxythiophene) (PEDOT) nanocomposite by one-pot synthesis method. Here, 3, 4-ethylenedioxythiophene (EDOT) is used as the reductant and polystyrene sulfonate (PSS-) as a dopant for PEDOT as well as particle stabilizer for silver nanoparticles (AgNPs). Agnano–PEDOT/PSS-nanocomposite was characterized by infrared (IR) spectroscopy, transmission electron microscopy (TEM). AgNPs are distributed uniformly around PEDOT polymer with an average particle size diameter of 10–15 nm and the nanocomposite film showed catalytic activity towards 4-nitro phenol. Some types of including Ag bimetallic nanoparticles and nanostructured materials could be directly applied for the electroanalysis and biosensing applications. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2045

    Effect of chitosan biopolymer and UV/TiO2 method for the de-coloration of acid blue 40 simulated textile wastewater

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    The purpose for this study is to de-color C.I. Acid Blue 40 simulated textile wastewater using chitosan and UV/TiO2 system. The methodology is to use chitosan biopolymer and UV/TiO2 to degrade textile wastewater and to measure the color removal by UV-visible spectrophotometer. The operational parameters are chitosan, TiO2, pH and reaction time. From the laboratory investigations, different efficiencies were observed according to different removal operating levels. Single chitosan of 2500 ppm dose was used to remove Acid Blue 40 textile wastewater and to obtain a better efficiency. TiO2 alone with UV light was also used with the dose of 2500 ppm to obtain a better efficiency. In acidity, both chitosan and TiO2 obtain better efficiencies under pH 4 operational condition. The best combination for UV/TiO2 system to de-color the 50 ppm Acid Blue 40 textile wastewater was TiO2 2500 ppm concentration with UV illumination at pH 4. The result shows that the de-colorization efficiency reached 98.8% elimination after 210 min of reaction time.Keywords: Chitosan biopolymer, UV/TiO2, Acid Blue 40, textile wastewater, spectrophotometerAfrican Journal of Biotechnology Vol. 9(34), pp. 5575-5580, 23 August, 201

    Maximizing Friend-Making Likelihood for Social Activity Organization

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    The social presence theory in social psychology suggests that computer-mediated online interactions are inferior to face-to-face, in-person interactions. In this paper, we consider the scenarios of organizing in person friend-making social activities via online social networks (OSNs) and formulate a new research problem, namely, Hop-bounded Maximum Group Friending (HMGF), by modeling both existing friendships and the likelihood of new friend making. To find a set of attendees for socialization activities, HMGF is unique and challenging due to the interplay of the group size, the constraint on existing friendships and the objective function on the likelihood of friend making. We prove that HMGF is NP-Hard, and no approximation algorithm exists unless P = NP. We then propose an error-bounded approximation algorithm to efficiently obtain the solutions very close to the optimal solutions. We conduct a user study to validate our problem formulation and per- form extensive experiments on real datasets to demonstrate the efficiency and effectiveness of our proposed algorithm
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