Sharif Digital Repository

Background: Purified terephthalic acid (PTA) wastewater from a petrochemical complex was utilized as a fuel in the anode of a microbial fuel cell (MFC). Effects of two important parameters including different dilutions of the PTA wastewater and pH on the performance of the MFC were investigated. Methods: The MFC used was a membrane-less single chamber consisted of a stainless steel mesh as anode electrode and a carbon cloth as cathode electrode. Both power density and current density were calculated based on the projected surface area of the cathode electrode. Power density curve method was used to specify maximum power density and internal resistance of the MFC. Results: Using 10-times,... 

Reduction of stress concentrations in the area of pin-loaded holes is one of the greatest challenges in the design of multilayered fibre-reinforced composite structures. Among many approaches to decrease concentration effects, putting metallic inserts in the holes is a convenient method. In this research, finite element analysis is applied to assess the effects of manufacturing parameters on stress concentration in the vicinity of the holes in composite plates with inserts. Edge and pitch distance, thickness and materials of insert, clearance between insert and composite part, and stiffness of the adhesive filling the gap are studied in this article. Investigations show that the optimum... 

The concentration and temperature behaviors of the self-diffusion coefficient were analyzed in glycerol-water and methanol-water solutions using Diffusion-Ordered Spectroscopy (DOSY) experiment. Our results indicate that the self-diffusion coefficient dips with increasing concentration and decreasing temperature. The concentration behavior shows that there is hydrogen bond interaction between water and alcohol, which declines the self-diffusion coefficients of both in the aqueous binary mixtures. The self-diffusion activation energies were estimated 13.6, 29.4, and 32.8 (kJ/mol) for methanol and 24.8, 25.5, and 27.6 (kJ/mol) for water in the methanol-water solutions with 0.03, 0.10, and 0.20... 

Characterization of droplet-hydrogel interfaces is of crucial importance to engineer droplet-hydrogel composites for a variety of applications. In order to develop electrokinetic diagnostic tools for probing droplet-hydrogel interfaces, the displacement of a charged droplet embedded in a polyelectrolyte hydrogel exposed to an oscillating electric field is determined theoretically. The polyelectrolyte hydrogel is modeled as an incompressible, charged, porous, and elastic solid saturated with a salted Newtonian fluid. The droplet is considered an incompressible Newtonian fluid with no charges within the droplet. The droplet-hydrogel interface is modeled as a surface with the thickness of zero... 

The control of thin film nanocomposite (TFN) membranes cross-linking degree is an important factor to design new membranes and optimizing permeation characteristics. The Fe3O4 nanoparticle's based TFN membranes due to potentially added magnetic responsive properties to the membrane has a great importance in developing membrane architectures. Fe3O4/polyamide (PA) TFN membranes filled with nanoparticles in different sizes and concentrations have been synthesized. Cross-linking degree of PA layer characterized with Fourier transform spectroscopy (FTIR) and x-ray photoelectron spectroscopy (XPS) methods to evaluate size dependency of the cross-linking degree of PA layer network. Obvious...