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Mosaddegh E.,Kerman Graduate University of Technology
Ultrasonics Sonochemistry | Year: 2013

The nano eggshell powder (NESP) has been prepared by ultrasound irradiation and used as a novel and biodegradable catalyst with high catalytic activity and reusability in green synthesis of 2-aminochromenes via condensation of α- or β-phathol, malononitrile and aromatic aldehydes at 120 C under solvent-free conditions. The reaction proceeds to completion within 10-35 min in 91-98% yield. Nano eggshell catalyst was characterized by scanning electron microscopy, X-ray powder diffraction, IR spectroscopy and X-ray fluorescence, thermal gravimetric, surface area and elemental analyses. In addition, the catalytic activity and chemical structure of nano-sized eggshell were compared with pure CaCO3. © 2013 Elsevier B.V. All rights reserved. Source

Karimi-Maleh H.,Kerman Graduate University of Technology | Biparva P.,Sari University of Agricultural Sciences and Natural Resources | Hatami M.,Khorramshahr Marine Science and Technology University
Biosensors and Bioelectronics | Year: 2013

A carbon paste electrode (CPE) modified with (9, 10-dihydro-9, 10-ethanoanthracene-11, 12-dicarboximido)-4-ethylbenzene-1, 2-diol (DEDE) and NiO/CNTs nanocomposite was used for the sensitive voltammetric determination of cysteamine (CA), nicotinamide adenine dinucleotide (NADH) and folic acid (FA) for the first time. The synthesized materials were characterized with different methods such as XRD, cyclic voltammetry, electrochemical impedance spectroscopy (EIS) and square wave voltammetry (SWV). The modified electrode exhibited a potent and persistent electron mediating behavior followed by well-separated oxidation peaks of CA, NADH and FA. The peak currents were linearly dependent on CA, NADH and FA concentrations using square wave voltammetry (SWV) method in the ranges of 0.01-250, 1.0-500, and 3.0-550μmolL-1, with detection limits of 0.007, 0.6, and 0.9μmolL-1, respectively. The modified electrode was used for the determination of CA, NADH and FA in biological and pharmaceutical samples. © 2013 Elsevier B.V. Source

Askarzadeh A.,Kerman Graduate University of Technology
International Journal of Hydrogen Energy | Year: 2013

Polarization curves of proton exchange membrane fuel cells (PEMFCs) are affected by various parameters. The relative importance and effect of each parameter on the polarization curve is different. This paper studies estimation of parameters with the most influence on the electrochemical model. In order to evaluate the obtained results, the model accuracy is compared with that model in which all the parameters are estimated. Because PEMFCs parameter estimation is a complex optimization problem, a recently invented nature-inspired algorithm, bird mating optimizer (BMO), is proposed. For this aim, two real systems, the SR-12 Modular PEM Generator and the Ballard Mark V FC, are considered. The obtained results show that when the whole parameters are estimated, the accuracy of the model increases. Also, BMO algorithm yields better results than the other studied methods in terms of precision and robustness. © 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. Source

Elyasi M.,Islamic Azad University | Khalilzadeh M.A.,Islamic Azad University | Karimi-Maleh H.,Kerman Graduate University of Technology
Food Chemistry | Year: 2013

based on Pt/CNTs nanocomposite ionic liquid modified carbon paste electrode (Pt/CNTs/ILCPE) using cyclic voltammetry, electrochemical impedance spectroscopy (EIS) and square wave voltammetry (SWV) methods. The novel sensor exhibited an obviously catalytic activity towards the oxidation of Sudan I, which can be confirmed by the increased oxidation peak current and the decreased oxidation peak potential when compared with the bare carbon paste electrode (CPE). The electron transfer coefficient (α), diffusion coefficient (D), and charge transfer resistance (Rct) of Sudan I at the modified electrode were calculated. The linear response range and detection limit were found to be 0.008-600 μmol L-1 and 0.003 μmol L-1, respectively. Other species did not interfere with the determination of Sudan I at a surface of propose sensor in the optimum condition. The proposed sensor was successfully applied for the determination of Sudan I in food samples with satisfactory results. © 2013 Elsevier Ltd. All rights reserved. Source

The importance of energy demand estimation stems from energy planning, formulating strategies and recommending energy policies. Most often, energy demand is mathematically formulated by socio-economic indicators. The challenging problem is to determine the optimal or near optimal weighting factors. Inspired by social behavior of bird flocking or fish schooling, PSO (particle swarm optimization) is a population-based search technique which has attracted significant attention to tackle the complexity of difficult optimization problems. This paper studies the performance of different PSO variants for estimating Iran's electricity demand. Seven PSO variants namely, original PSO, PSO-w (PSO with weighting factor), PSO-cf (PSO with constriction factor), PSO-rf (PSO with repulsion factor), PSO-vc (PSO with velocity control), CLPSO (comprehensive learning PSO) and a MPSO (modified PSO), are used to find the unknown weighting factors based on the data from 1982 to 2003. The validation process is then conducted by testing the optimized models by using the data from 2004 to 2009. It is seen that PSO-vc produces more promising results than the other variants, HS (harmony search) and ABSO (artificial bee swarm optimization) algorithms in terms of MAPE (mean absolute percentage error). This value is obtained 2.47 and 2.50 for the exponential and quadratic models, respectively. © 2014 Elsevier Ltd. Source

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