Numerical study of electrical characteristics of conjugated polymer light-emitting diodes

Conjugated polymers now provide a class of processible, film-forming semiconductors and metals. In this work, the electronic properties of polymer lightemitting diodes devices are numerically studied. Our results show how an insulating buffer layer with suitable thickness decreases the barrier height at the cathode and therefore increases the electron injection. We also discuss the effects from persistent charged traps

Influence of the nature of cation on water splitting at the interface of a cation exchange membrane during electrodialysis

The phenomenon of water splitting occuring at the interface of a Selemion CMV cation exchange membrane in contact with solutions containing successively monovalent, divalent and trivalent cations was investigated. Under identical hydrodynamic conditions, this investigation is based on recording j-V curves, measurement of transport numbers and pH variations. Water splitting is not a direct consequence of concentration polarization phenomenon. The cation nature and especially its acidic character is an important parameter which explains the difference in the behavior of the Selemion CMV membrane in contact with solutions of different cations

An optimization model for a mechanical vapor compression desalination plant driven by a wind/PV hybrid system

A renewable hybrid system to produce domestic water is presented. It consists of a photovoltaic module, a wind turbine, a mechanical vapor compression desalination plant and a storage unit. An optimization model based on a mathematical programming is developed to control the energy flows exchanged among the system components in order to satisfy the domestic water demand. The model has been solved for three specific case studies in Morocco, where two of them are located in Rabat which aim to satisfy the hourly and monthly water demand of 20 households, whereas, the last one is in Essaouira, which aims to ensure the monthly water demand of 40 households. The main motivations behind selecting these specific case studies are the evaluation of the efficiency and feasibility of such system in two coastal sites having different characteristics of renewable energy sources. The obtained results show that the domestic water demands are satisfied in each time interval at a reasonable economic cost comparable to the current average cost of water in Morocco which is about 0.7 \u20ac m3

Comparaison des performances de deux membranes commerciales de nanofiltration dans la défluoruration d’une eau souterraine

Les problèmes de la pollution des eaux souterraines par les fluorures se posent de plus en plus au Maroc notamment dans les régions phosphatières. Des solutions alternatives au traitement telles que la dilution ou l’abandon ne sont plus viables à court terme. Pour éviter cette situation, l’Office National de l’Eau Potable (ONEP) a entrepris des études en collaboration avec l’Université Ibn Tofail pour trouver d’autres solutions. Le traitement est désormais une nécessité. Ce travail porte sur une étude de défluoration d’une eau souterraine par nanofiltration à l’aide d’un pilote industriel (fourni par la société TIA, Techniques Industrielles Appliquées). Les performances de deux membranes commerciales dans la réduction des ions fluorures sont confirmées. Les configurations simple passe et double passe ont été testées. Un test longue durée a été mené pour confirmer les performances dans le temps du pilote industriel de nanofiltration

Study the performance of the organic membrane ultrafiltration on whey treatment

Treatment of whey using the organic membrane processes namely ultrafiltration (UF) was investigated to recover the proteins for re-use. Membrane module was tested in batch mode operations and multi-stages operations employing the influence of the pH and temperature. The performance of ultrafiltration membrane can be characterized permeate flux and membrane retention, these parameters are determined by pH and temperature. The influence of these parameters on whey protein concentrate is also measured.nbspThe permeate flux and the protein content in the permeate and in the concentrate fractions were measured during the experimental runs. By comparing the separation behavior of the membrane for the two separation modes it was found that the investigated membrane produced the best results from the point of permeate flux, VRF and protein content in multi-stage modes in optimal condition (pH=6.5 and Temperature 50degC). The filtration characteristics were obviously influenced by the process parameters