An explicit numerical model for the charge balancing ion transfer across monopolar ion exchange membranes under conditions of bioelectrochemical systems is presented. Diffusion and migration equations have been solved according to the Nernst-Planck Equation and the resulting ion concentrations, pH values and the resistance values of the membrane for different conditions were computed. The model...

sulfonated poly (ether ether ketone) (speek) with a low degree of sulfonation (ds = 40%) was prepared for proton exchange membrane fuel cells (pemfc). poly (ether ether ketone) (peek) was sulfonated in concentrated h2so4 under n2 atmosphere and characterized by the hydrogen nuclear magnetic resonance (h-nmr) technique. after preparation of the speek polymer, the obtained polymer was dissolved i...

The combined effect of both concentration and pressure differences on electrical potential (Ad~) for two ion-exchanger membranes, one positively charged (AE) and another negatively charged (CE), measured with the membranes in contact with NaCI solutions was studied. Results show a linear dependence between Adp and pressure, independently if AC and AP have the same or opposite directions. The ra...

Within an electrodialysis unit, the solutions are separated by alternately arranged anion exchange membranes (permeable only for anions) and cation exchange membranes (permeable only for cations). The membranes are arranged parallel to one another to form an electrodialysis stack. When a potential is applied across the selectively permeable membrane stack, anions selectively move through the an...

A difference in salt concentration in two solutions separated by a membrane leads to an electrical potential difference across the membrane, also without applied current. A literature study is presented on proposed theories for the origin of this membrane potential (ϕm). The most well-known theoretical description is Teorell-Meyer-Sievers (TMS) theory, which we analyze and extend. Experimental ...

Proton exchange membranes for fuel cells were synthesized from the blend of copolymers of vinyl acetate-acrylic ester and styrene-acrylic ester, which were modified by sulfonation and addition of silica gel. Water uptake, ion exchange capacity, infrared spectroscopy and tensile tests were applied to characterize the prepared membranes. The results show that the prepared membranes with the proce...

as igm and iga-enriched preparations are needed to complete the immunotherapeutic spectrum, a simple procedure is described for the preparation of igm and iga enriched immunoglobulins. fraction iii which was prepared by cold ethanol fractionation was treated by octanoic acid followed by ethanol precipitation and ion-exchange chromatography using sephadex deae a-50 and 0.1 m tris-d.35m naci buff...

the main goal of this study is to investigate the capability of zeolites a and p synthesized from iranian natural clinoptilolite for uranium uptak. the removal of uranium(vi) from aqueous solution via ion exchange by zeolites in a single component system with various contact times,  temperatures and initial concentrations of uranium(vi) was investigated. the experimental results were fitted to ...

a difference in salt concentration in two solutions separated by a membrane leads to an electrical potential difference across the membrane, also without applied current. a literature study is presented on proposed theories for the origin of this membrane potential (ϕm). the most well-known theoretical description is teorell-meyer-sievers (tms) theory, which we analyze and extend. experimental ...