Thermal conductivity and diffusion coefficient of polymer blend 80%EP/20%UPE reinforced with sand particles

New polymer blend with enhanced properties was prepared from (80 %) epoxy resin (Ep), (20%) unsaturated polyester resin (UPE) as a matrix material. The as-obtained polymer blend was further reinforced by adding Sand particles of particle size (53 μm) with various weight fraction (5, 10, 15, 20 %). Thermal conductivity and sorption measurements are performed in order to determine diffusion coefficient in different chemical solutions (NaOH, HCl) with concentration (0.3N) after immersion for specific period of time (30 days). The obtained results demonstrate that the addition of sand powder to (80%EP/20%UPE) blend leads to an increase of thermal conductivity, with an optimum/minimum diffusion coefficient in (HCl)/(NaOH), respectively.

MODELING OF SELF–HEALING MATERIALS AND FITTING PARAMETERS PROCEDURE

The surface defects of the material are difficult to detect and difficult to repair. A big challenge in materials science is to design „smart“ synthetic systems that can re-establish the continuity and integrity of the damaged area. Recent research of the nanocontainers with the process of self-healing materials promises a good avenue for new smart nanocoating interfaces. We use continuum modeling approach to investigate coating substrates that contain nanoscale defects with healing agents. Here we use Finite Element Method (FEM) with different diffusivity and fluxes. The fitting procedure from simulations is performed to determine diffusion coefficient and the diameter of nanocontainers to match experimental results. We also show the risk map from the calculations of the creepage and coverage.

Mass Transport Properties of a Flow-Through Electrolytic Reactor Using Zinc Reduction System

An electrolytic process for the removal of Zn(II) from aqueous solution using a parallel amalgamated copper screens cathode operated in the flow through mode is proposed. The current-potential curves recorded at a rotating amalgamated copper disc electrode were used to determine diffusion coefficient of Zn(II). The performance of electrolytic reactor was investigated by using different flow rates at initial zinc ion concentration(48 mg/L). Taking into account the residential Zn(II) concentration, the best results were obtained for cathode potential of (-1.35 V vs. SCE) at flow rate (320 L/h). Zinc ion concentration was found to decrease from 48 mg/L to 1 mg/L during 120 min. of electrolysis. The experimental data are well correlated in term of Sherwood and Reynolds numbers based on the wire diameter of woven screen for characteristic length .Empirical correlation characterized the mass transport properties of the reactor is: Sh = 8.077 Re0.363.